WO2014160757A2 - Independent tunig of audio devices employing electroactive polymer actuators - Google Patents

Independent tunig of audio devices employing electroactive polymer actuators Download PDF

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Publication number
WO2014160757A2
WO2014160757A2 PCT/US2014/031830 US2014031830W WO2014160757A2 WO 2014160757 A2 WO2014160757 A2 WO 2014160757A2 US 2014031830 W US2014031830 W US 2014031830W WO 2014160757 A2 WO2014160757 A2 WO 2014160757A2
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WO
WIPO (PCT)
Prior art keywords
electroactive polymer
ear
actuator
actuators
frequency
Prior art date
Application number
PCT/US2014/031830
Other languages
French (fr)
Other versions
WO2014160757A3 (en
Inventor
Dirk Schapeler
Roger N. Hitchcock
Damion Nicholas ENGELBART
Glenn Raymond DECASTRO
Andrew Shu-an CHENG
Silmon James Biggs
Original Assignee
Bayer Materialscience Ag
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by Bayer Materialscience Ag filed Critical Bayer Materialscience Ag
Publication of WO2014160757A2 publication Critical patent/WO2014160757A2/en
Publication of WO2014160757A3 publication Critical patent/WO2014160757A3/en

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Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61HPHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H23/00Percussion or vibration massage, e.g. using supersonic vibration; Suction-vibration massage; Massage with moving diaphragms
    • A61H23/02Percussion or vibration massage, e.g. using supersonic vibration; Suction-vibration massage; Massage with moving diaphragms with electric or magnetic drive
    • A61H23/0218Percussion or vibration massage, e.g. using supersonic vibration; Suction-vibration massage; Massage with moving diaphragms with electric or magnetic drive with alternating magnetic fields producing a translating or oscillating movement
    • A61H23/0236Percussion or vibration massage, e.g. using supersonic vibration; Suction-vibration massage; Massage with moving diaphragms with electric or magnetic drive with alternating magnetic fields producing a translating or oscillating movement using sonic waves, e.g. using loudspeakers
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00Details of transducers, loudspeakers or microphones
    • H04R1/10Earpieces; Attachments therefor ; Earphones; Monophonic headphones
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R17/00Piezoelectric transducers; Electrostrictive transducers
    • H04R17/005Piezoelectric transducers; Electrostrictive transducers using a piezoelectric polymer
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R5/00Stereophonic arrangements
    • H04R5/02Spatial or constructional arrangements of loudspeakers
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61HPHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2201/00Characteristics of apparatus not provided for in the preceding codes
    • A61H2201/16Physical interface with patient
    • A61H2201/1602Physical interface with patient kind of interface, e.g. head rest, knee support or lumbar support
    • A61H2201/1604Head
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61HPHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2201/00Characteristics of apparatus not provided for in the preceding codes
    • A61H2201/16Physical interface with patient
    • A61H2201/1602Physical interface with patient kind of interface, e.g. head rest, knee support or lumbar support
    • A61H2201/165Wearable interfaces
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61HPHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2201/00Characteristics of apparatus not provided for in the preceding codes
    • A61H2201/50Control means thereof
    • A61H2201/5002Means for controlling a set of similar massage devices acting in sequence at different locations on a patient
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61HPHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2201/00Characteristics of apparatus not provided for in the preceding codes
    • A61H2201/50Control means thereof
    • A61H2201/5005Control means thereof for controlling frequency distribution, modulation or interference of a driving signal
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61HPHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2205/00Devices for specific parts of the body
    • A61H2205/02Head
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61HPHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2205/00Devices for specific parts of the body
    • A61H2205/02Head
    • A61H2205/027Ears
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R25/00Deaf-aid sets, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception
    • H04R25/60Mounting or interconnection of hearing aid parts, e.g. inside tips, housings or to ossicles
    • H04R25/604Mounting or interconnection of hearing aid parts, e.g. inside tips, housings or to ossicles of acoustic or vibrational transducers

Definitions

  • the present disclosure relates generally to electroactive polymer devices. More particularly, the present disclosure relates to independently tunable electroactive polymer devices such as audio devices.
  • the same type of device may be referred to as a generator.
  • the structure when the structure is employed to convert physical stimulus such as vibration or pressure into an electrical signal for measurement purposes, it may be characterized as a sensor.
  • the term "transducer” may be used to genetically refer to any of the devices.
  • electroactive polymer materials also referred to as “electroactive polymers,” for the fabrication of transducers. These considerations include potential force, power density, power conversion/consumption, size, weight, cost, response time, duty cycle, service requirements, environmental impact, etc. As such, in many applications, electroactive polymer technology offers an ideal replacement for piezoelectric, shape-memory alloy and electromagnetic devices such as motors and solenoids.
  • An electroactive polymer transducer comprises two electrodes having deformable characteristics and separated by a thin elastomeric dielectric material
  • the oppositely charged electrodes attract each other thereby compressing the polymer dielectric layer therebetween.
  • the dielectric polymer film becomes thinner (the Z-axis component contracts) as it expands in the planar directions (along the X- and Y-axes), i.e., the displacement of the film is in-plane.
  • the electroactive polymer film may also be configured to produce movement in a direction orthogonal to the film structure (along the Z-axis), i.e., the displacement of the film is out-of-plane.
  • U.S. Pat, No. 7.567.6 1 discloses electroactive polymer film constructs which provide such out-of-plane displacement- also referred to as surface deformation or as thickness mode deflection.
  • the materia] and physical properties of the electroactive polymer fi lm may be varied and controlled to customize the deformation undergone by the transducer. More specifically, factors such as the relative elasticity between the polymer film and the electrode material, the relative thickness between the polymer film and electrode material and/or the varying thickness of the polymer film and/or electrode material, the physical pattern of the polymer film and/or electrode material (to provide localized active and inactive areas), the tension or pre-strain placed on the electroactive polymer film as a whole, and the amount of voltage applied to or capacitance induced upon the film may be controlled and varied to customize the features of the film when in an active mode.
  • the headphones comprise at least one conventional acoustic speaker which provides a sonic response by providing sound waves that travel through the ear canal to vibrate the ear drum as well as at least one electroactive polymer actuator that induces vibrations in the bone and tissue surrounding the ear which are experienced as conductive audio response through bone conduction.
  • the at least one electroactive polymer actuator is driven by a high voltage signal that is derived from the same low-voltage audio signal that drives the acoustic speaker although it may have been processed to enhance speci fic regions of the frequency spectrum, particularly low frequencies that are difficult to achieve with acoustic speakers. While over- the-ear and on-ear headphones comprising electroactive polymer actuators have been demonstrated, it has been more difficult to incorporate these actuators into in-ear headphones or earphones.
  • a device comprises at least two electroactive polymer actuators that are spatially separated, wherein each actuator is driven with a signal controlling frequency and amplitude.
  • a different drive signal is used for each actuator. The different drive signals may be chosen such that they provide an interference beat at yet a third set of frequencies.
  • the device is an audio device that further comprises at least one acoustic speaker which is optionally driven at a set of frequencies and amplitude different from at least one of the electroactive polymer actuators.
  • the drive signals of the electroaetive polymer actuators may be chosen such that they provide an interference beat and may provide a binaural conductive audio response.
  • the conductive audio response may be entirely distinct from the sonic audio response from the acoustic speaker, in one embodiment, the conductive audio response is designed to couple to brain waves that can lead to stress relief, relaxation or stimulation of a user of the audio device.
  • the audio device is an over-the-ear or on-ear headphone.
  • the audio device is an in-ear headphone or earphone.
  • the earphone may have a configuration which decouples the sound tube from the earphone case to accommodate an electroactive polymer actuator and accompanying high voltage leads.
  • Electroactive polymer devices that can be used with these designs include, but are not limited to planar, diaphragm, thickness mode, roll, and passive coupled devices (hybrids) as well as any type of electroactive polymer device described in the commonly assigned patents and applications cited herein.
  • FIGS. 1 A and I B illustrate a top perspective view of a transducer before and after application of a voltage in accordance with the present invention
  • FIG. 2 A illustrates an exemplary electroactive polymer cartridge in accordance with the present invention
  • FIG. 2B illustrates an exploded view of an electroactive polymer actuator, inertial mass and actuator housing in. accordance with the present invention
  • FIG. 3 is a cutaway view of an electroactive polymer system to illustrate the principle of operation in accordance with the present invention
  • FIG, 4 is a schematic diagram of an electroactive polymer system to illustrate the principle of operation in accordance with the present invention
  • FIG. 5 is an exploded side view of an audio device comprising independent control of frequency and volume levels for each channel in accordance with the present invention
  • FIG. 6 is a level control switch for independent control of volume and vibration levels for each channel of the audio device shown in FIG , 5;
  • FIG, 7 is an exploded view of an audio device comprising an independently tunable electroactive polymer actuator in accordance with the present invention
  • FIG. 8 is a cross-sectional view of the audio device shown in FIG . 7;
  • FIG. 9 is a diagram of a electroactive polymer /acoustic audio device in accordance with the present invention.
  • FIG. 10 is a block diagram of an electronic topology for an independently tunable actuator electronic system in accordance with the present invention.
  • FIG. 11 is a graphical depiction of acoustic response of a headphone with electroactive polymer actuators turned on;
  • FIG. 12 is a graphical depiction of acoustic response of the headphones with electroactive actuators of FIG. 1 1 turned on and actuator gains set to minimum;
  • FIG . 13 is a graphical depiction of acceleration of headphone ear cups versus frequency measured on a Head And Torso Simulator (HATS);
  • HATS Head And Torso Simulator
  • FIG. 14 is a graphical depiction of acceleration of headphone ear cups comprising electroactive polymer actuators versus frequency measured on a human test subject;
  • FIG. 15 is a cross-sectional view of a hub-mounted audio device located inside the ear canal in accordance the present invention.
  • FIG . 16 is a cross-sectional view of a wall mounted audio device located inside the ear canal in accordance with the present invention.
  • FIG. 17 is a cross-sectional view of a fully potted audio device located inside the ear canal in accordance with the present invention.
  • FIG. 18 is a diagram of a conventional earphone
  • FIG. 19 is a diagram of an earphone in accordance with the present invention.
  • FIGS. 20A-2GD illustrate placement of electroactive polymer actuator in an ear bud in accordance with the present invention
  • FIG. 21 is a graphical depiction of frequency response of the ear bud shown in FIGS. 20A-20D in accordance with the present invention.
  • FIG. 22 illustrates an improved potting fixture for placing the electroactive polymer actuator into ear buds in accordance with the present invention
  • FIGS. 23A-23D illustrate an electroactive polymer actuator placement in an ear bud in accordance with the present invention
  • FIG. 24 is a graphical depiction of a finite element analysis rough draft model prediction of movement of the electroactive polymer actuator within the ear bud;
  • FIG. 25 A is a graphical depiction of measured movement consistent with the prediction shown in FIG. 24 in accordance with the present invention.
  • FIG. 25B is a sectional view of the ear bud and the electroactive polymer actuator mounted therein in accordance with the present invention.
  • FiG. 26 is illustrates high potential voltage (HiPot) testing of an electroactive polymer actuator enhanced ear bud in accordance with the present invention
  • FIG. 27 shows an electroactive polymer actuator enhanced ear bud made according to the process described in connection with FIG. 26;
  • FIGS, 28A-28C illustrate some additional movement strategies such as a piston mode (FIG. 28 A), a bender mode (FIG. 28B) and a basket mode (FIG. 28C) in accordance with the present invention
  • FIGS. 29A and 29B illustrate potential issues arising out of the piston mode movement shown in FIG. 28A;
  • FIGS. 30 and 31 illustrate the bender mode previously discussed in connection with FIG. 28B;
  • FIG. 32A is an exploded view of a unimorph electroactive polymer actuator including relative dimensions thereof in accordance with the present invention
  • FIG. 32B is an assembled view of the unimorph electroaciive polymer actuator shown in FIG. 32A;
  • FIG. 33 is an assembled view of several uniraorph electroaciive polymer actuators shown in FIGS. 32A and 32B in accordance with the present invention.
  • FIG. 34 is a graphical depiction of measured movement of roll bender
  • FIG. 35A illustrates spring rate on tension roll from loaded hoops in accordance with the present invention
  • FIG. 35B is a graphical depiction of force as a function of stretch ratio
  • FIG. 36 illustrates a diagram of the human ear.
  • 2007/0230222 201 1/0128239; 2012/0126959; 2012/0126667; 2012/0206248; 2013/0002587; 2013/0194082; and in PCT Publication Nos.: WO/201 1/097020; WO/2012/099850;
  • FIGS. 1-4 provide a brief description of eieciroactive polymer structures.
  • FIGS, 1 A and IB illustrate an example of an eieciroactive polymer film or membrane 10 structure.
  • a thin elastomeric dielectric film or layer 12 is sandwiched between compliant or stretchable electrode plates or layers 14 and 16, thereby forming a capacitive structure or film.
  • the length "L” and width "w" of the dielectric layer, as well as that of the composite structure, are much greater than its thickness "t".
  • the dielectric layer has a thickness in the range from about 10 ⁇ to about 100 ⁇ , with the total thickness of the structure in the range from about 15 ⁇ to about 10 cm.
  • Electrodes suitable for use with these compliant capacitive structures are those capable of withstanding cyclic strains greater than about 1% without failure due to mechanical fatigue.
  • “deflection” refers to any displacement, expansion, contraction, torsion, linear or area strain, or any other deformation of a portion of dielectric film 12.
  • this deflection may be used to produce mechanical work.
  • transducer architectures are disclosed and described in the above-identified patent references,
  • the transducer film 10 With a voltage applied, the transducer film 10 continues to deflect until mechanical forces balance the electrostatic forces driving the deflection.
  • the mechanical forces include elastic restoring forces of the dielectric layer 12, the compliance or stretching of the electrodes 14, 16 and any external resistance provided by a device and/or load coupled to transducer 10.
  • the resultant deflection of the transducer 10 as a result of the applied voltage may also depend on a number of other factors such as the dielectric constant of the
  • the electrodes 14 and 16 may cover a limited portion of dielectric film 12 relative to the total area of the film. This may be done to prevent electrical breakdown around the edge of the dielectric or achieve customized deflections in certain portions thereof. Dielectric material outside an active area (the latter being a portion of the dielectric material having sufficient el ectrostati c force to enable deflection of that portion) may be caused to act as an external spring force on the active area during deflection. More specifically, material outside the active area may resist or enhance active area deflection by its contraction or expansion.
  • the dielectric film 12 may be pre-strained.
  • the pre-strain improves conversion between electrical and mechanical energy, i.e., the pre-strain allows the dielectric film 12 to deflect more and provide greater mechanical work.
  • Pre-strain of a film may be described as the change in dimension in a direction after pre-straining relative to the dimension in that direction before pre-straining.
  • the pre-strain may include elastic deformation of the dielectric film and be formed, for example, by stretching the film in tension and fixing one or more of the edges while stretched.
  • the pre-strain may be imposed at the boundaries of the film or for only a portion of the film and may be implemented by using a rigid frame or by stiffening a portion of the film.
  • FIG. 2A illustrates an exemplary electroactive polymer cartridge 12 having an electroactive polymer transducer film 26 placed between rigid frame 8 where the
  • electroactive polymer film 26 is exposed in openings of the frame 8.
  • the exposed portion of the film 26 includes three working pairs of thin elastic electrodes 32 on either side of the cartridge 12 where the electrodes 32 sandwich or surround the exposed portion of the film 26.
  • the electroactive polymer film 26 can have any number of configurations.
  • the electroactive polymer film 26 comprises a thin layer of elastomeric dielectric polymer (e.g., made of acrylate, silicone, urethane, thermoplastic elastomer, hydrocarbon rubber, fluoroelastomer, copolymer elastomer, or the like).
  • the opposed electrodes attract each other thereby compressing the dielectric polymer layer 26 therebetween.
  • the area between opposed electrodes is considered the active area.
  • the dielectric polymer 26 becomes thinner (i.e., the Z- axis component contracts) as it expands in the planar directions (i.e., the X- and Y-axes components expand) (See Figs. IB for axis references).
  • electrodes contain conductive particles, like charges distributed across each electrode may cause conductive particles embedded within that electrode to repel one another, thereby contributing to the expansion of the elastic electrodes and dielectric films
  • electrodes do not contain conductive particles (e.g., textured sputtered metal films).
  • the dielectric layer 26 is thereby caused to deflect with a change in electric field.
  • the electrode layers change shape along with dielectric layer 26.
  • deflection refers to any displacement, expansion, contraction, torsion, linear or area strain, or any other deformation of a portion of dielectric layer 26, This deflection may be used to produce mechanical work.
  • the dielectric layer 26 can also include one or more mechanical output regions or bars 34, The regions or bars 34 can optionally provide attachment points for either an inertial mass (as described below) or for direct coupling to a substrate in the electronic media device.
  • an elastic film 26 can be stretched and held in a pre- strained condition usually by a rigid frame 8.
  • the film can be stretched bi -a ial ly.
  • pre-strain improves the dielectric strength of the polymer layer 26. thereby enabling the use of higher electric fields and improving conversion between electrical and mechanical energy, i.e., the pre-strain allows the film to deflect more and provide greater mechanical work.
  • the electrode material is applied after pre-straining the polymer layer, but may be applied beforehand.
  • the opposed electrodes on the opposite sides of the polymer layer form two sets of working electrode pairs, i.e., electrodes spaced by the electroactive polymer film 26 form one working electrode pair and electrodes surrounding the adjacent exposed electroactive polymer film 26 form another working electrode pair.
  • Each same-side electrode pair can have the same polarity, whereas the polarity of the electrodes of each working electrode pair is opposite each other.
  • Each electrode has an electrical contact portion configured for electrical connection to a voltage source.
  • the electrodes 32 are connected to a voltage source via a flex connector 30 ha ving leads 22, 24 that can be connected to the opposing poles of the voltage source.
  • the cartridge 12 also includes conductive vias 18, 20.
  • the conductive vias 18, 2(1 can provide a means to electrically couple the electrodes 8 with a respective lead 22 or 24 depending upon the polarity of the electrodes.
  • the cartridge 12 illustrated in FIG. 2A shows a 3-bar actuator configuration.
  • the devices and processes described herein are not limited to any particular configuration, unless specifically claimed.
  • the number of the bars 34 depends on the active area desired for the intended application.
  • the total amount of active area e.g., the total amount of area between electrodes, can be varied depending on the mass that the actuator is trying to move and the desired frequency of movement, in one example, selection of the number of bars is determined by first assessing the size of the object to be moved, and then the mass of the object is determined. The actuator design is then obtained by configuring a design that will move that object at the desired frequency range.
  • any number of actuator designs is within the scope of the disclosure,
  • electroactive polymer actuator for use in the processes and devices described herein can then be formed in a number of different ways.
  • the electroactive polymer can be formed by stacking a number of cartridges 12 together, having a single cartridge with multiple layers, or having multiple cartridges with multiple layers.
  • Manufacturing and yield considerations may favor stacking single cartridges together to form the electroactive polymer actuator. In doing so, electrical connectivity between cartridges can be maintained by electrically coupling the vias 18, 20 together so that adjacent cartridges are coupled to the same voltage source or power supply.
  • the cartridge 12 shown in FIG. 2A includes three pairs of electrodes 32 separated by a single dielectric layer 26, in one variation, as shown in FIG. 2B, two or more cartridges 12 are stacked together to form an electroactive actuator 14 that is coupled to an inertial mass 50.
  • the electroactive actuator 14 can be coupled directly to the electronic media device through an intermediary attachment plate or frame.
  • the electroactive actuator 14 may be placed within a cavity 52 that allows for movement of the actuator as desired.
  • the pocket 52 may be directly formed in a housing of a case.
  • pocket 52 may be formed in a separate case 56 positioned within the housing of the device.
  • the material properties of the separate case 56 may be selected based upon the needs of the actuator 14.
  • the main body of the housing assembly is flexible, the separate case 56 can be made rigid to provide protection to the electroactive actuator and/or the mass SO.
  • variations of the device and processes described herein include size of the cavity 52 with sufficient clearance to allow movement of the actuator 14 and/or mass 50 but a close enough tolerance so that the cavity 52 barrier (e.g., the housing or separate case 56) serves as a limit to prevent excessive movement of the electroactive actuator 14. Such a feature prevents the active areas of the actuator 14 from excessive displacement that can shorten the life of the actuator or otherwise damage the actuator.
  • FIGS. 3-4 provide a description of an electroactive polymer based module suitable for use in the devices such as headphones.
  • FIG. 3 is a partial cutaway view of an
  • the system comprises an electroactive polymer module 200.
  • An electroactive polymer actuator 222 is configured to slide an output plate 202 (e.g., sliding surface) relative to a fixed plate 204 (e.g., fixed surface) when energized by a voltage "V."
  • the plates 202, 204 are separated by steel balls, and have features that constrain movement to the desired direction, limit travel, and withstand drop tests.
  • the top plate 202 may be attached to an inertial mass.
  • Segmenting the electroactive polymer actuator 222 within a given footprint into (n) sections is a convenient method for setting the passive stiffness and blocked force of the electroactive polymer system.
  • a pre-stretched dielectric is held in place by the rigid material that defines an external frame such as the fixed plate 204 and one or more windows within the frame. Inside each window is an output bar 212 of the same rigid frame material, and on one or both sides of the output bar 212 are electrodes 208.
  • an adhesive may replace the rigid frame material as disclosed in co-assigned PCT Publication No.
  • electroactive polymer modules 200 are the advantages of electroactive polymer modules 200 .
  • electroactive polymer modules 200 consume low power, and are well suited for customizable design and performance options.
  • the electroactive polymer module 200 is representative of electroactive polymer modules developed by Artificial Muscle, inc., of Sunnyvale, CA, USA.
  • many of the design variables of the electroactive polymer module 200 may be fixed by the needs of module integrators while other variables (e.g., number of dielectric layers, operating voltage) may be constrained by cost. Because actuator geometr - the allocation of footprint to rigid supporting structure versus active dielectric - does not impact cost much, it may be a reasonable way to tailor performance of the eiectroactive polymer module 200 to an application where the module 200 is integrated with headphones or other device,
  • Computer implemented modeling techniques can be employed to gauge the merits of different actuator geometries, such as: (1) Mechanics of the Handset/User System; (2) Actuator Performance; and (3) User Sensation. Together, these three components provide a computer-implemented process for estimating the capability of candidate designs and using the estimated capability data to select an eiectroactive polymer design suitable for mass production. The model predicts the capability for two kinds of effects: long effects (e.g. gaming and music), and short effects (e.g. key clicks). "Capability" is defined herein as the maximum sensation a module can produce in service. Such computer-implemented processes for estimating the capability of candidate designs are described in more detail in commonly assigned PCT Publication No, WO/2011/102898, the entire disclosure of which is hereby incorporated by reference.
  • FIG . 4 is a schematic diagram of an eiectroactive polymer system 300 designed to illustrate the principle of operation of eiectroactive polymer modules.
  • the eiectroactive polymer system 300 comprises a power source 302, shown as a low voltage direct current (DC) battery for illustrative purposes, electrically coupled to an eiectroactive polymer module 304.
  • the power source (Vsatt) represents the output of an audio signal source configured to generate low frequency audio signals below about 200 Hz, for example, and in one embodiment between about 2 Hz to about 200 Hz, where the term "about” stands for ⁇ 10%.
  • the eiectroactive polymer module 304 comprises a thin elastomeric dielectric element 306 disposed (e.g., sandwiched) between two conductive electrodes 308A, 308B.
  • the conductive electrodes 3 ⁇ 8 ⁇ , 308B are stretchable (e.g., conformable) and may be printed on the top and bottom portions of the elastomeric dielectric element 306 using any suitable technique, such as, for example screen printing.
  • the eiectroactive polymer module 304 is activated by coupling the battery 302 (e.g., signal source) to an actuator circuit 310 by closing a switch 312,
  • the actuator circuit 310 converts the low DC voltage Vsatt signal into a higher DC voltage ⁇ 7 iR signal suitable for driving the eiectroactive polymer module 304.
  • an additional circuit may be located within the opening 124 defined by the housing 118, where the circuit is configured to convert the low voltage low frequency audio signal from the audio signal source, to a higher voltage signal suitable for driving the electroactive polymer actuator 122 as shown in FIGS, 1 A-1B,
  • displacement may be amplified by a suitable configuration of electroactive polymer actuators.
  • FIG. 5 is an exploded side view of an electroactive polymer device 400 comprising independent tuning of motion and volume levels for each channel in accordance with present invention.
  • the electroactive polymer device is shown in the form of a headphone.
  • the electroactive polymer device 400 comprises a headband 402 and first and second ear cushions 404i, 4042, first and second speakers 406i 5 4062, first and second drive electronics 408i, 4082, first and second electroactive polymer actuators 410i, 4102, and first and second ear cups 412i, 4122.
  • the "first” components correspond to a first channel of the electroactive polymer device 400 and the "second" components correspond to the second channel of the electroactive polymer device 400.
  • FIG. 6 is a level control switch 420 for independent control of volume and motion levels for each channel of the audio device 400 shown in FIG. 5.
  • the level control switch 420 comprises four separate switches 422s, 4222, 424i, 424 2 , to control left speaker 406i volume, right speaker 4062 volume, left electroactive polymer actuator 410i. and right electroactive polymer actuator 4 ⁇ 2, respectively.
  • the level control switch 420 provides independent control of motion from the electroactive polymer actuators 410i, 41( and sound volume from the speakers 406i, 062 for the electroactive polymer device 400.
  • the level control switch 420 comprises a first volume control switch 422i to control the volume level of the first speaker 4061 and a second volume control switch 422 2 to control the volume level of the second speaker 406 2 independently.
  • the level control switch 420 also comprises a first vibration control switch 424i to control the motion level of the first electroactive polymer actuators 410i and a second vibration control switch 4242 to control the motion level of the second eleetroactive polymer actuators 4102 independently.
  • the present invention allows custom and independent tuning of the motions produced by the eleetroactive polymer actuators 410i, 410 2 and the sound volume and content produced by the speakers 406s, 406 2 for each side of the eleetroactive polymer device 400.
  • the user could tune the sound volume level of the first speaker 4061 to 6 and using the 1 to 10 level control switch 424i the user could tune the motion level of the first eleetroactive polymer actuator 410i to 8 on the first side (e.g., right side).
  • the user could tune the sound volume level of the second speaker 4062 to 4 and using the 1 to 10 level control switch 424 2 the user could tune the motion level of the second eleetroactive polymer actuator 4102 to 3 on the second side (e.g., left side).
  • the combination of independent volume and motion tuning control can be advantageous for individuals that are hard of hearing because the technology allows someone to feel their music including frequencies that a person may not be able to hear.
  • being able to independently tune the eleetroactive polymer actuators 41 ⁇ , 410 2 is advantageous because users may have asymmetric hearing loss. For example, someone with hearing loss may have 80% hearing loss in the right ear and have only 60% hearing loss in the left ear. Thus, someone with that profile may want to turn up the volume level as well as the eleetroactive polymer actuator level on the right side but turn down the volume level and the eleetroactive polymer actuator level on the left side, relative to the right side. Even if an individual does not have hearing loss, they may prefer to experience different levels of motion by the eleetroactive polymer actuator (conductive audio response) on one ear versus the other.
  • eleetroactive polymer device 400 speaker volume level as well as eleetroactive polymer actuator level may be integrated either directly into the eleetroactive polymer device 400 ear cups 412j, 412 2 or as a separate wired or wireless controller.
  • the following description is directed to relaxation headphones including eleetroactive polymer actuators.
  • Low frequency phenomena may induce improved states of relaxation (see, ⁇ 80 ⁇ and ILiGHTZ products as examples).
  • coupling low frequency vibrations or sounds to the human body may better help people to relax.
  • Some methods use large chairs or apparatus which is not easily moved or easily transported.
  • Other techniques use standard headphones and sound waves in an attempt to provide a transportable relaxation apparatus.
  • conventional headphones do not directly produce sound waves at the frequencies of interest, most acoustic methods use frequency differences of fairly high frequencies, for example 400 Hz and 405 Hz, to obtain a 5 Hz difference.
  • a sonic audio response due to sound waves may not be as effective at coupling into a human body as a conductive audio response which can be transmitted by the skeletal system.
  • FIG. 7 is an exploded view of a device 430 comprising an electroactive polymer actuator 432 in accordance with the present invention.
  • FIG. 8 is a cross-sectional view of the audio device 430 shown in FIG. 7 in accordance with the present, invention.
  • the audio device 430 comprises an electroactive polymer actuator 432 attached to an exterior portion of a sound cavity cover 436.
  • a speaker 438 is located within the cavity defined by the sound cavity cover 436.
  • a speaker housing 440 is rigidly attached to an ear cup housing 434 and supports the speaker 438, the sound cavity cover 436, and the electroactive polymer actuator 432 therebetween.
  • a cushion 442 may be attached to the speaker housing 440.
  • the acoustic cavity may be: (1) open; (2) closed; or (3) closed with an acoustic port.
  • the electroactive polymer actuator 432 e.g., electroactive polymer motion element or module
  • the electroactive polymer actuator 432 is coupled directly to the sound cavity cover 436 portion of the audio device 430, which is rigidly attached to the speaker housing 440 and the cushion 442.
  • the surface outside of the sound cavity cover 436, behind the speaker 438 may be utilized to mount the electroactive polymer actuator 432.
  • the electroactive polymer actuator 432 may be integrated in over-the-ear and on-the- ear headphones to improve the user experience by enhancing the low frequency content of the audio being played.
  • the electroactive polymer actuator 432 may preferably be attached to a rigid flat surface, such as the back of the sound cavity cover 436, on one side and to a suspended mass on the other side.
  • the electroactive polymer actuator 432 moves the mass relative to the speaker housing 440. according to the low frequency portion of the audio signals it receives.
  • a suspended mass attached to the speaker housing 440 through the electroaciive polymer actuator 432 results in a mass-spring-damper system.
  • the movement direction of the electroaciive polymer actuator 432 may be best when oriented in parallel plan relative to the ear, orthogonal to the axis of the acoustic driver (to minimize acoustic artifacts).
  • the electroactive polymer device depicted in FIGS. 7 and 8 may be employed to create binaural frequencies that humans may feel.
  • the created effect influences the theta brainwaves of humans inducing the brain to enter a state of deep relaxation.
  • the device 430 includes a pair of headphones in which a pair of electroactive polymer actuators 432 has been mounted.
  • Stereo electronics, discussed below in connection with FIGS. 9-1 1, provide for full independent left and right side motion
  • the electroactive polymer actuators 432 are dynamic and can be controlled to a wide variety of sensations and effects. With electroactive polymer actuators 432, the device 430 may generate frequencies that cannot be heard but be felt by humans to influence the theta brainwaves. Relaxation experts may be able to design better programs using such an electroactive polymer actuator 432 enabled low-frequency device 430. Humans may enter a relaxation state for their body and brain on a button press and using a mobile device.
  • Most audio content can be delivered as a two-channel, real-time analog signal such as stereo music, for example.
  • the audio content may be delivered as streaming digital information.
  • the analog audio signals may be processed to extract meaningful content.
  • This real-time content may be directed to the electroactive polymer actuators 432 to produce compelling motion/acoustic effects.
  • FIGS. 9-1 1 describe an electronics system design that may be employed to operate the electroactive polymer devices 400. 430 described in connection with FIGS. 4-8. As to each device 400, 430, the electronics system may require a unique implementation based on its features and specific design, therefore the electronics system described herein is generic.
  • the audio source 502 delivers audio content as two two-channel realtime analog signals.
  • the audio source 502 may deliver streaming digital information.
  • the audio source 502 includes any one of a PC, IPOD, IPHONE, USB, 3.5 mm, stereo, among other audio sources 502.
  • the audio source 502 outputs a one or two channel acoustic signal 504 and a one or two channel motion signal 506.
  • the acoustic and motion signals 504, 506 are processed to extract meaningful content.
  • the acoustic signal 504 is processed by acoustic electronic system 508 and the motion signal 506 is processed by an act uator electronic system 514.
  • the user may provide input 526 in any of the audio source 502, the acoustic electronic system 508, or the actuator electronic system 514.
  • the acoustic electronic system 508 may comprise relatively simple audio electronics or more sophisticated digital signal processing (DSP) electronic circuits.
  • DSP digital signal processing
  • the acoustic electronic system 508 may comprise passive or active noise canceling circuits.
  • the acoustic electronic system 508 includes a left channel output section SIOi and a right channel output section 5102 to independently drive left and right speakers 512i, 5122, respectively.
  • the left and right speakers 512», 5122 produce stereo sound with independent volume level control.
  • one output signal may be used to drive both speakers 512i, 5122 at once.
  • Both amplitude and frequency of the low voltage electrical signals output from the left channel output section 510i and the right channel output section 51 2 are independently tunable.
  • the motion signal 506 is processed by the actuator electronic system 514 to extract meaningful content.
  • the actuator electronic system 514 comprises a signal processing section 522 and a high voltage amplifier section 524.
  • the signal processing section 522 receives the motion signal 506 from the audio source 502 and prepares the signal for feeding into the high voltage amplifier section 524.
  • the high voltage amplifier section 524 includes a left channel output section Si 6i and a right channel outpu section 51 2 to independently drive left and right electroactive polymer actuators 518s, SI82, respectively, in the direction indicated by arrows 520i, 5202, respectively.
  • the real-time motion signal 506 is thus directed to the electroactive polymer actuators 518i, 5182 to produce compelling motion effects.
  • one output signal may be used to drive both electroactive polymer actuators 518i, 518 2 at once. Both amplitude and frequency of the high voltage electrical signals output from the left channel output section 5161 and the right channel output section 5I62 are independently tunable.
  • FIG. 10 is a block diagram 600 of an electronic topology for an independently tunable actuator electronic system in accordance with the present invention
  • the actuator electronic system 600 is suitable for independently driving electroactive polymer actuators, such as the electroactive polymer actuators 518j, SiSi described in connection with FIG. 9.
  • a variety of signal conditioning, amplifying, compensating, and driving circuits are also implemented, in particular, an analog audio signal module 602 receives analog motion signals from a differential amplifier source, or any suitable source.
  • the differential amplifier may be implemented with any suitable integrated circuit amplifier.
  • the low frequency digital filter module 606 may be implemented using any suitable circuit technique and may comprise a microcontroller and a programmable gate array circuit, among other digital or analog processing circuit elements. In one embodiment, the low frequency digital filter module 606 may be implemented with any suitable programmable system, such as, for example a programmable system-on-chip controller.
  • a low frequency amplifier module 608 amplifies the output of the low frequency digital filter 6 ⁇ 6 and the output is passed to the programmable gate array circuit.
  • the low frequency amplifier module 608 may be implemented using any- suitable integrated circuit amplifier.
  • the output of the low frequency digital filter 606 is provided to a non-linear in verse transform circuit (square root circuit) such as an inverse polynomial circuit 610, which provides the electronic audio signal compensation to remove unwanted distortions in the audio signal used to move the electroactive polymer actuators.
  • a non-linear in verse transform circuit square root circuit
  • the inverse polynomial circuit 610 approximates an inverse function to linearize the electroactive polymer actuators, for example.
  • the inverse polynomial circuit 610 may be implemented using integrated circuits, programmable circuits, piecewise linear circuits and/or any combinations thereof.
  • a piecewise linear circuit can be used to approximate a non-linear function, such as sine, square-root, logarithmic, exponential, and the like, for example.
  • the quality of the approximation depends on the number of segments employed by the piecewise linear circuit and the strategy used in determining the segments.
  • the diode approach has the advantage of simplicity but the disadvantages Include temperature dependence on the switching thresholds and relatively slow response.
  • the saturating amplifier method has the disadvantage of complexity but the advantages of minimal temperature dependence on thresholds and high speed
  • the inverse polynomial circuit 610 may be implemented as a compression or an expansion circuit, each type having a different circuit topology
  • a compression circuit compresses the dynamic range of an input signal whereas an expansion circuit expands the dynamic range.
  • Examples of compression circuits include square-root, logarithmic, and sine and generally employ nonlinear voltage divider techniques.
  • One example of an expansion circuit is an exponential function.
  • a combination of compression and expansion circuits may be employed to implement the inverse polynomial circuit 610 to linearize electroactive polymer actuators, for example.
  • One embodiment of a piece wise linear circuit using diode switching to approximate an inverse square-root function may be employed.
  • the output of the inverse -?2- polynomial circuit 610 is provided to a high voltage power amplifier 612 for amplification to a level sufficient to drive the electroactive polymer actuator module.
  • the voltage required to drive the electroactive polymer actuator module may range from a few hundred volts (V) to several thousand volts fkV), with a nominal driving voltage of about 1 kV.
  • a left channel output 614L of the high voltage amplifier 612 is provided to a left reflex actuator and mass 6.16L, e.g., to an electroactive polymer actuator located in a left ear cup of the
  • a right channel output 6I4R of the high voltage amplifier 612 is provided to a right reflex actuator and mass 61611, e.g., to an electroactive polymer actuator located in a right ear cup of the headphones.
  • single phase actuators can be improved using a square root circuit in the sensory enhanced headphones comprising electroactive polymer actuators.
  • Non-linear control techniques also may be employed in multi-phase actuators, for example.
  • in one embodiment of the present invention provides an apparatus for applying binaural frequencies that a human can feel. For example, if a person is in beta stage (highly alert) and a stimulus of 1GHz is applied to his/her brain for some time, the brain frequency is likely to change towards the applied stimulus. The effect will feel relaxing to the person; a phenomenon known as "frequency following response.”
  • Electroactive polymer actuators and driving techniques described in connection with FIGS. 5-1.0 may be used to generate motion signals to stimulate the brain using a binaural technique.
  • the stimulus may be applied using binaural beats. If the left element is presented with a steady tone of 500Hz and the right element a steady tone of 510Hz, these two tones combine in the brain. The difference, 10Hz, is perceived by the brain and is a very effective stimulus for brainwave entrainment. This lOHz is formed entirely by the brain.
  • the devices described in connection with FIGS. 5-10 mat be employed to move one side of a person's head with a first motion signal at a first frequency (fi) and the other side of the person's head with a second motion signal at a second frequency ( 3 ⁇ 4.
  • the left and right motion signals do not mix together, but rather constructively interfere to create a binaural beat with a frequency roughly equal to the frequency difference ( ⁇ / ' fi - fi) which is perceived by brain. .
  • motion signals of 50Hz and 60Hz, or 40Hz and 50 Hz, or 80Hz and 90Hz should be applied.
  • the electronic system 600 described in FIG. 10 is configured to respond to signals between ⁇ THz and ⁇ 150Hz.
  • the eiectroactive polymer actuators have a mechanical resonance around 44 Hz when placed on a human subject. Optimum frequencies are in approximately the 20 Hz to 80 Hz range,
  • the motion level in each channel can be independently controlled to customize the binaural effect using electroactive polymer actuators, in one embodiment, where the devices have independently controlled acoustic and motion levels, the binaural stimulus may be enhanced using a combination of audible frequencies and motion frequencies to generate binaural stimulus to the brain.
  • Table 1 below depicts the effect of binaural beats.
  • FIGS. 11-14 are graphical depiction of test results conducted with a modified ATH- M50 Headphones.
  • the headphones included three bar/two layer actuators installed into flexure modules using a 26 g inertial mass, as described by way of example in FIGS. 2 A and 2B. Only one bar of three was connected to the mass which reduced the spring constant by a factor of three. This resulted in a significantly lower mechanical resonant irequency than the typical headphones used for audio enhancement.
  • the acoustic volume levels and actuator motion levels may be operated independently or together as described in connected with FIGS. 5-10, This is a full stereo system with independent gains on both actuators.
  • FIG. 1 1 is a graphical depiction 700 of acoustic response of a headphone with electroactive polymer actuators turned on. Frequency (Hz) is shown along the horizontal axis on a logarithmic scale and Acoustic Response
  • FIG. 12 is a graphical depiction 710 of acoustic response of the headphones with electroactive actuators in FIG. 1 1 turned on and actuator gains set to minimum.
  • Frequency (Hz) is shown along the horizontal axis on a logarithmic scale and Acoustic Response jy(f)
  • FIG. 13 is a graphical depiction 720 of acceleration of headphone ear c ps versus frequency measured on a Head And Torso Simulator (HATS).
  • HATS Head And Torso Simulator
  • Frequency (Hz) is shown along the horizontal axis on a logarithmic scale and Acceleration (g) is shown along the vertical axis.
  • the resonant frequency measured on HATS (B&K 4128c Head and Torso Simulator) was about 53 Hz but measures around 44 Hz when placed on a human test subject (see FIG. 14).
  • the vertical scaling on FIG. 13 is 0.0312 was 0.1 g peak (0.2 g's peak-to-peak).
  • Left and right vertical (Y) axis and horizontal (X) axis acceleration was measured versus vibration frequency of the electroactive polymer actuator. As shown in FIG. 12, four curves were plotted: the left X-axis 726, the left Y-axis 722, the right X-axis 728, and the right Y- axis 724. Because the electroactive polymer actuators were configured to move primarily In the X-direction relative to the Y-direction, as shown in FIG. 12, the right X-axis and the left X-axis 726 accelerations were greater than the corresponding right Y-axis 724 and left Y-axis 722 accelerations.
  • F IG. 14 is a graphical depiction 730 of acceleration of headphone ear cups comprising electroactive polymer actuators versus frequency measured on a human test.
  • Frequency (Hz) is shown along the horizontal axis on a logarithmic scale and Acceleration (g) is shown along the vertical axis.
  • the resonant frequency measured is about 44 Hz when placed on a human test subject.
  • the vertical scaling on FIG. 13 is 0.0312 is 0.1 g peak (0.2 g's peak-to-peak). As shown in FIG.
  • FIGS. 5-17 illustrate three approaches to conforming an integrated electroactive polymer actuator/ear bud into an ear.
  • FIG. 15 is a cross-sectional view of a hub-mounted audio device 800 located inside the ear canaS 80S in accordance with one embodiment of the present invention.
  • the hub- mounted audio device 800 comprises a wall 806 and a potted electroactive polymer actuator 804 mounted about a hub 802.
  • an inner portion 810 of the potted electroactive polymer actuator 804 contacts an outer surface 812 abut the perimeter of the hub 802 and outer portions 814 of the electroactive polymer actuator 804 contact inner portions of the wall 806 whereas other surfaces 816, 817 of the electroactive polymer actuator 804 do not contact the wall 806 and rather define openings 818, 819 between the wall 806 and the outer surfaces 816, 817.
  • the openings 818, 819 are separated by the hub 802 and potted electroactive polymer 804.
  • FIG. 16 is a cross-sectional view of a wall-mounted audio device 820 located inside the ear canal 808 in accordance with one embodiment of the present invention.
  • the wall- mounted audio device 820 comprises a wall 826 and a potted electroactive polymer actuator 824 mounted to the wall 826 rather than a hub 822.
  • an outer surface 828 of the potted electroactive polymer 824 contacts an inner portion of the wall 826 about the perimeter thereof.
  • Portions 830 on an inner surface of the potted electroactive polymer 824 contact the hub 822 and defines openings 832, 834 between portions 836, 838 of the potted electroactive polymer actuator 824 and outer surfaces of the hub 822.
  • FIG. 1 7 is a cross-sectional view of a fully potted audio device 840 located inside the ear canal 808 in accordance with one embodiment of the present invention.
  • the fully potted audio device 840 comprises a hub 842, a potted electroactive polymer actuator 844, and a wall 846.
  • the potted electroactive polymer actuator 844 occupies the entire space between the inner surface 848 of the wall 846 and the outer surface 852 of the hub 842. Accordingly, the outer surface 850 of the potted electroactive polymer actuator 844 is in contact with the inner surface 848 of the wall 846 and the inner surface 854 of the potted electroactive polymer actuator 844 is in contact with the outer surface 852 of the hub 842.
  • FIG. 18 is a diagram of a conventional earphone 860.
  • the conventional earphone 860 includes a rigid case back 862, a rigid case front 864, and a flexible rubber ear bud 866.
  • a rigid sound tube 868 is molded into the rigid case front 864.
  • the conventional earphone 860 is built using two pieces, with the rigid sound tube 868 rigidly attached to the rigid front case 864 of the earphone 860.
  • FIG. 19 is a diagram of an earphone 870 in accordance with the present invention.
  • the earphone 870 comprises a rigid case back 872, a rigid case front 874, and a flexible rubber ear bud 876.
  • a rigid sound tube 878 is formed as an integral feature of the otherwise flexible rubber ear bud 876.
  • the end 884 of the sound tube 878 is attached to the rigid case front 874, for example using adhesive, snap-fit, or ultrasonic welding. This provides a
  • the new configuration of the earphone 870 described in FIG. 19 decouples the rigid sound tube 878 from the rigid front case 874 of the earphone 870 to accommodate an electroactive polymer actuator and accompanying high voltage leads 880, 882.
  • This embodiment of the present invention integrates the di electric elastomer actuator into the ear bud 876 insert portion of the earphone 870 as described in connection with FIGS. 15-17. The assembly safely shields the electroactive polymer actuator and the high voltage wires 880, 882 to minimize the risk of shock,
  • the high voltage wires 880, 882 are routed inside the protective rigid case front 872 at the eariiest possible point, minimizing shock hazard.
  • the earphone 870 provides a rigid foundation for building up the flexible ear bud 876, enabling better precision when molding in or otherwise integrating the electroactive polymer actuator into the ear hud 876, as discussed in connection with FIGS, 15-17.
  • the earphone 870 configuration shown in FIG. 19 enables the designers to control space that was previously taken up by the rigid "sound tube" of the rigi d case front and the "hub" of the flexible ear bud. As space is at a premium in the ear canal it is helpful to be able to minimize the radial thickness of these passive parts, and leave more room for the electroactive polymer actuator.
  • FIGS. 20A-20D illustrate placement of electroactive polymer actuator 890 in an ear bud 876 in accordance with the present invention.
  • the ear bud 876 is coupled to the rigid front case 874.
  • the high-voltage wires 880, 882 are electrical ly coupled to the electroactive polymer 890 and in FIGS. 20A, 20B are seen exiting the end of the rigid front case 874.
  • the electroactive polymer 890 are located within a cavity 892 formed inside the flexible ear bud 876, As shown in FIG. 20D, the electroactive polymer 890 are in contact with the wall of the ear bud 876 but not the hub 892.
  • FIG. 21 is a graphical depiction of frequency response of the ear bud 876 shown in FIGS. 20A-20D in accordance with the present invention.
  • the acoustic response was adequate.
  • a cast silicone ear and canal was considered ideal as it would match body stiffness: (Shore 00 35).
  • An LDM laser was shined through the silicone to measure movement of a laser dot on the ear bud surface. The LDM laser was moved to get multiple points.
  • ear bud 876 For electrical insulation, zero-defect isolation of .8 kV is required and the insulation must not over-constrain movement. Because the ear bud 876 surface has compound curvature, it requires precise molds and fixtures. Other desirable methods of manufacturing the ear bud 876 include machining or 3D printing,
  • FIG. 22 illustrates an impro ved potting fixture 900 for placing the electroactive polymer actuator 890 into ear buds 876 in accordance with the present invention.
  • the electroactive polymer 876 and the high voltage wires 880, 882 located through various openi ngs 902 formed on a cover portion of the potting fixture 900.
  • the ear buds 876 are aligned along corresponding receiving holes 906 formed in a bottom case portion 908 of the potting fixture 900.
  • the electroactive polymer 890 electrically coupled to the high voltage wires 880. 882 are inserted into openings 910 formed in the ear buds 876 and the entire assembly is then inserted into receiving holes 906 in the bottom case 908 where the assembly is potted,
  • FIGS. 23A-23D are photographs showing an electroactive polymer actuator 890 placement in an ear bud 876 in accordance with the present invention.
  • the electroactive polymer actuator 890 electrically coupled to high-voltage wires 880, 882 is sho wn to the left of a secti oned portion of the ear bud 876.
  • a detail view of the sectioned ear bud 876 is shown in FIG. 23C.
  • FIGS. 23B and 231) show sectional views of the electroactive polymer actuator 890 mounted inside the ear bud 876
  • FIG. 24 is a graphical depiction of a finite element analysis rough draft model prediction of movement of the electroactive polymer actuator 890 within the ear bud 876.
  • FIG. 25 A is a graphical depiction 920 of measured movement consistent, with the prediction shown in FIG. 24 in accordance with the present invention.
  • F G. 25B is a sectional vie w of the ear bud 876 and the electroactive polymer actuator 890 mounted therein in accordance with the present invention.
  • electroactive polymer actuator 890 one slab, potted in a potting compound, 1.8 kV, free stroke was used to generate the data for FIG. 25A.
  • the angle ⁇ was varied from -5 degrees to 60 degrees and the measurements plotted in the graph 920 shown in FIG. 25A were taken at - 5 degrees, 10 degrees, 30 degrees, and 60 degrees.
  • the solid triangles (A) represent 60 degrees; the solid circles ( ⁇ ) represent 30 degrees; the solid squares (ss) represent 10 degrees; and the solid diamonds ( ) represent -5 degrees.
  • the amplitude distribution was consistent with finite element rough draft shown in FIG. 24. The direction also agreed (field on radius reduced), whereas the peak amplitude was lower than the model.
  • FIG. 26 is a photograph depi cting the results of high potential voltage (HiPot) testing of an electroactive polymer actuator enhanced ear bud in accordance with the present invention.
  • HiPot high potential voltage
  • the tactile sensation was detected in pinch grip (3/3 subjects).
  • a tactile sensation was detected in the ear canal (3/3 subjects) and was reported to be not annoying (3/3).
  • FIGS. 28A-28C illustrate some additional movement strategies such as a piston mode (FIG. 28A), a bender mode (FIG. 28B) and a basket mode (FIG. 28C) in accordance with the present invention. As shown in FIG. 28 A, in piston mode the motion is along the
  • the electroactive polymer actuator 930 As shown in FIG. 28A, excitation by a voltage potential causes electroactive polymer actuator 930 to elongate by Ad in the longitudinal direction defined by the electroactive polymer actuator 930, In FIG. 28B, in bender mode the electroactive polymer actuator 932 bends under a force F like a beam for a displacement, in the Y direction of Ay relative to x 0 by an angle of ⁇ ⁇ . In the basket mode shown in FIG. 28C, the electroactive polymer 934 is shaped like a basket and is capable of expanding and collapsing under the influence of a high-voltage potential between the HY+ and GND wires.
  • FIGS, 29 A and 29B illustrate some potential issues arising out of the piston mode movement depicted in FIG. 28A, In the piston mode, the electroactive polymer actuator 930 stack or roll may buckle instead of elongating in the longitudinal direction defined by the electroactive polymer actuator 930.
  • FIGS. 30 and 31 illustrate the bender mode previously discussed in connection with FIG. 28 B.
  • the bending angle ⁇ is determined and in FIG. 31, the Ay displacement is determined.
  • the straight beam 932 is represented by the expression:
  • the angle ⁇ is small -3.2° and is calculated according to the following:
  • FIG. 32A is an exploded view of a unimorph electroactive polymer actuator 940 including relative dimensions thereof in accordance with the present invention.
  • FIG. 32B is an assembled view of the unimorph electroactive polymer actuator 940 shown in FIG. 32A.
  • the unimorph electroactive polymer actuator 940 comprises an electroactive polymer roll 942, an electrically insulated sheet 944, and an electrical conductor 946.
  • FIG. 33 is photograph showing several unimorph electroactive polymer actuators 940.
  • FIG. 34 is a graphical depiction 942 of measured movement of roll bender
  • FIG. 35 A illustrates spring rate on tension roll from loaded hoops 945 in accordance with the present invention.
  • FIG. 35B is a graphical depiction 947 of force as a function of stretch ratio. From pure geometry, about a 30% increase in force can be achieved using a linear spring on the hoop. Bui this would require a great fattening of the electroactive polymer actuator. 10 degrees is about acceptable. But this only gives strain of 1 ,5%. Many smaller hoops at about 40 degrees could be acceptable. -20 degrees gives 6% strain; 30 degrees gives 1 5% strain; 40 degrees gives 30% strain. Nonlinear (strain softening) hoop spring could increase the steepness of the negative rate.
  • the force F is calculated as follows:
  • An average human ear canal is about 26 mm in length and 7 mm in diameter.
  • the outer part of the canal consists of a cartilaginous soft body and a 0.5 - 1 .0 mm thick skin with glands and hair follicles.
  • the glands produce ear wax, which has an important role in keeping the ear canal clean and protecting it from bacteria, fungi and insects.
  • the outer soft part of the canal forms one third to one half of total canal length.
  • the remaining inner part of the canal rests on the opening of the bony skul! and the skin in this part of the canal is tightly applied to the bone.
  • the skin here is approximately 0.2 mm thick and it may be easily injured or ruptured.
  • FIG. 36 is a diagram of the human ear 1000.
  • Applied sound pressure 1002 at the ear eana! entrance 1 04, radiated sound pressure at the ear canal entrance 1004, applied force or displacement at the actuator attachment points 1008, and displacement of the footplate center in the direction of the longitudinal stapes axis 1010 are shown.
  • An eiectroactive polymer device comprising: first and second eiectroactive polymer actuators which are spatially separated, each of the eiectroactive polymer actuators comprising an eiectroactive polyraer film, at least one pair of opposing compliant electrodes, and at least one mechanical output region, wherein the mechanical output region is configured to move in response to an activation signal being applied to the eiectroactive polymer film; wherein the first eiectroactive polymer actuator is configured to receive a first high voltage electrical signal and the second eiectroactive polymer actuator is configured to receive a second high voltage electrical signal, wherein the first and second high voltage electrical signals are independently tunable in both frequency and amplitude.
  • the electroactive polymer device according to clause 4 further comprising at least a second acoustic speaker which is configured to receive a second low voltage electrical signal that is tunable in both frequency and amplitude independently from the electroactive polymer actuators.
  • the device comprises an in-the-ear audio device, further comprising: a first rigid case back; a first rigid case front; a first flexible rubber ear bud; wherein the first electroactive polymer actuator is located within the flexible ear bud.

Abstract

The disclosure provides a device having first and second electroactive polymer actuators, each one of the electroactive polymer actuators comprising an electroactive polymer film, a pair of opposing compliant electrodes, and at least one mechanical output region. The mechanical output region is configured to move in response to an activation signal being applied to the electroactive polymer film to provide a movement. The first and second electroactive polymer actuators are independently tunable in frequency and amplitude to provide motion independently. Also disclosed are audio devices configured as over-the ear-headphones and in-the-ear headphones.

Description

INDEPENDENT TUNING OF AUDIO DEVICES EMPLOYING
ELECTROACTIVE POLYMER ACTUATORS
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit, under 35 USC § 1 19(e), of United States provisional patent application numbers: 61/805,269, filed March 26, 2013, entitled "IN-EAR HEADPHONES WITH DIELECTRIC ELASTOMER ACTUATORS," 61/813,886, filed April 19, 2013, entitled "EARPHONE DESIGN TO INTEGRATE DIELECTRIC
ELASTOMER," 61/846,669, filed July 16, 2013, entitled "INDEPENDENT TUNING OF VIVITOUCH AND VOLUME LEVELS FOR HEADPHONES," and 61/868,245, filed August 21 , 2013, entitled "RELAXATION HEADPHONES USING VIVITOUCH
ACTUATORS" the entire disclosure of each of which is hereby incorporated by reference.
FIELD OF THE 1NVE!
[0002] In various embodiments, the present disclosure relates generally to electroactive polymer devices. More particularly, the present disclosure relates to independently tunable electroactive polymer devices such as audio devices.
BACKGROUND OF THE INVENTION
[0003] A tremendous variety of devices used today rely on actuators of one sort or another to convert electrical energy to mechanical energy. Conversely, many power generation applications operate by converting mechanical action into electrical energy.
Employed to harvest mechanical energy in this fashion, the same type of device may be referred to as a generator. Likewise, when the structure is employed to convert physical stimulus such as vibration or pressure into an electrical signal for measurement purposes, it may be characterized as a sensor. Yet, the term "transducer" may be used to genetically refer to any of the devices.
[0004] A number of design considerations favor the selection and use of advanced dielectric elastomer materials, also referred to as "electroactive polymers," for the fabrication of transducers. These considerations include potential force, power density, power conversion/consumption, size, weight, cost, response time, duty cycle, service requirements, environmental impact, etc. As such, in many applications, electroactive polymer technology offers an ideal replacement for piezoelectric, shape-memory alloy and electromagnetic devices such as motors and solenoids. [0005] An electroactive polymer transducer comprises two electrodes having deformable characteristics and separated by a thin elastomeric dielectric material When a voltage difference is applied to the electrodes, the oppositely charged electrodes attract each other thereby compressing the polymer dielectric layer therebetween. As the electrodes are pulled closer together, the dielectric polymer film becomes thinner (the Z-axis component contracts) as it expands in the planar directions (along the X- and Y-axes), i.e., the displacement of the film is in-plane. The electroactive polymer film may also be configured to produce movement in a direction orthogonal to the film structure (along the Z-axis), i.e., the displacement of the film is out-of-plane. U.S. Pat, No. 7.567.6 1 discloses electroactive polymer film constructs which provide such out-of-plane displacement- also referred to as surface deformation or as thickness mode deflection.
[0006] The materia] and physical properties of the electroactive polymer fi lm may be varied and controlled to customize the deformation undergone by the transducer. More specifically, factors such as the relative elasticity between the polymer film and the electrode material, the relative thickness between the polymer film and electrode material and/or the varying thickness of the polymer film and/or electrode material, the physical pattern of the polymer film and/or electrode material (to provide localized active and inactive areas), the tension or pre-strain placed on the electroactive polymer film as a whole, and the amount of voltage applied to or capacitance induced upon the film may be controlled and varied to customize the features of the film when in an active mode.
[0007] Recent advances in headphone technology have incorporated electroactive polymer actuators into headphones to enhance audio qualify as described in PCT Publication No. WO/2012/173669, the entire disclosure of which is hereby incorporated by reference. The headphones comprise at least one conventional acoustic speaker which provides a sonic response by providing sound waves that travel through the ear canal to vibrate the ear drum as well as at least one electroactive polymer actuator that induces vibrations in the bone and tissue surrounding the ear which are experienced as conductive audio response through bone conduction. The at least one electroactive polymer actuator is driven by a high voltage signal that is derived from the same low-voltage audio signal that drives the acoustic speaker although it may have been processed to enhance speci fic regions of the frequency spectrum, particularly low frequencies that are difficult to achieve with acoustic speakers. While over- the-ear and on-ear headphones comprising electroactive polymer actuators have been demonstrated, it has been more difficult to incorporate these actuators into in-ear headphones or earphones.
[0008] While independent volume tuning of individual acoustic speakers on stereo headphones already exists, incorporation of electroactive polymer actuator technology for headphones and audio devices generally is still new. Conventional technology for headphones and audio devices generally does no allow custom tuning of electroactive polymer actuator generated conductive audio responses and volume level control independent of the sonic audio response and volume for eac side of a pair of headphones or speakers, generally.
[0009] It is known that low frequency phenomena can induce improved states of relaxation, Coupling low frequency vibrations or sounds to the human body can help people to better relax. Some conventional methods use large chairs or apparatus that are not easily moved or transported. Other methods use standard headphones and sound waves in an attempt to have transportable relaxation apparatus. In some eases, sound waves with different frequencies are introduced in each ear to elicit a binaural response. Because conventional headphones do not directly produce sound waves at the frequencies of interest, most acoustic methods use frequency differences of fairly high frequencies (for example, 400 Hz and 405 Hz to get a 5 Hz difference). Most other methods of adding vibration use eccentric rotating masses attached to electric motors. These are not dynamic and result in monotonic vibrations with a very narrow range of operating frequencies. The incorporation of electroactive polymer actuators that can be independently driven over a broad range of amplitudes and frequencies of interest can enable many new applications.
SUMMARY OF THE INVENTIO
[0010] Accordingly, the present invention provides various devices integrated with electroactive polymer actuators to provide independently controllable or tunable acoustic and conductive audio stimulation. In one embodiment, a device comprises at least two electroactive polymer actuators that are spatially separated, wherein each actuator is driven with a signal controlling frequency and amplitude. In one embodiment, a different drive signal is used for each actuator. The different drive signals may be chosen such that they provide an interference beat at yet a third set of frequencies. [0011] in another embodiment, the device is an audio device that further comprises at least one acoustic speaker which is optionally driven at a set of frequencies and amplitude different from at least one of the electroactive polymer actuators. The drive signals of the electroaetive polymer actuators may be chosen such that they provide an interference beat and may provide a binaural conductive audio response. The conductive audio response may be entirely distinct from the sonic audio response from the acoustic speaker, in one embodiment, the conductive audio response is designed to couple to brain waves that can lead to stress relief, relaxation or stimulation of a user of the audio device.
[0012] In another embodiment, the audio device is an over-the-ear or on-ear headphone. In another embodiment, the audio device is an in-ear headphone or earphone. The earphone may have a configuration which decouples the sound tube from the earphone case to accommodate an electroactive polymer actuator and accompanying high voltage leads.
[0013] Electroactive polymer devices that can be used with these designs include, but are not limited to planar, diaphragm, thickness mode, roll, and passive coupled devices (hybrids) as well as any type of electroactive polymer device described in the commonly assigned patents and applications cited herein.
[0014] These and other advantages and benefits of the present invention will be apparent from the Detailed Description of the invention herein below.
BRIEF DESCRIPTION OF THE FIGURES
[0015] The present invention will now be described for purposes of illustration and not limitation in conjunction with the figures, wherein:
[0016] FIGS. 1 A and I B illustrate a top perspective view of a transducer before and after application of a voltage in accordance with the present invention;
[0017] FIG. 2 A illustrates an exemplary electroactive polymer cartridge in accordance with the present invention;
[0018] FIG. 2B illustrates an exploded view of an electroactive polymer actuator, inertial mass and actuator housing in. accordance with the present invention;
[0019] FIG. 3 is a cutaway view of an electroactive polymer system to illustrate the principle of operation in accordance with the present invention; [0020] FIG, 4 is a schematic diagram of an electroactive polymer system to illustrate the principle of operation in accordance with the present invention;
[0021] FIG. 5 is an exploded side view of an audio device comprising independent control of frequency and volume levels for each channel in accordance with the present invention;
[0022] FIG. 6 is a level control switch for independent control of volume and vibration levels for each channel of the audio device shown in FIG , 5;
[0023] FIG, 7 is an exploded view of an audio device comprising an independently tunable electroactive polymer actuator in accordance with the present invention;
[0024] FIG. 8 is a cross-sectional view of the audio device shown in FIG . 7;
[0025] FIG. 9 is a diagram of a electroactive polymer /acoustic audio device in accordance with the present invention;
[0026] FIG. 10 is a block diagram of an electronic topology for an independently tunable actuator electronic system in accordance with the present invention;
[0027] FIG. 11 is a graphical depiction of acoustic response of a headphone with electroactive polymer actuators turned on;
[0028] FIG. 12 is a graphical depiction of acoustic response of the headphones with electroactive actuators of FIG. 1 1 turned on and actuator gains set to minimum;
[0029] FIG . 13 is a graphical depiction of acceleration of headphone ear cups versus frequency measured on a Head And Torso Simulator (HATS);
[0030] FIG. 14 is a graphical depiction of acceleration of headphone ear cups comprising electroactive polymer actuators versus frequency measured on a human test subject;
[0031] FIG. 15 is a cross-sectional view of a hub-mounted audio device located inside the ear canal in accordance the present invention;
[0032] FIG . 16 is a cross-sectional view of a wall mounted audio device located inside the ear canal in accordance with the present invention;
[0033] FIG. 17 is a cross-sectional view of a fully potted audio device located inside the ear canal in accordance with the present invention;
[0034] FIG. 18 is a diagram of a conventional earphone; [0035] FIG. 19 is a diagram of an earphone in accordance with the present invention;
[0036] FIGS. 20A-2GD illustrate placement of electroactive polymer actuator in an ear bud in accordance with the present invention;
[0037] FIG. 21 is a graphical depiction of frequency response of the ear bud shown in FIGS. 20A-20D in accordance with the present invention;
[0038] FIG. 22 illustrates an improved potting fixture for placing the electroactive polymer actuator into ear buds in accordance with the present invention;
[0039] FIGS. 23A-23D illustrate an electroactive polymer actuator placement in an ear bud in accordance with the present invention;
[0040J FIG. 24 is a graphical depiction of a finite element analysis rough draft model prediction of movement of the electroactive polymer actuator within the ear bud;
[0041] FIG. 25 A is a graphical depiction of measured movement consistent with the prediction shown in FIG. 24 in accordance with the present invention;
[0042] FIG. 25B is a sectional view of the ear bud and the electroactive polymer actuator mounted therein in accordance with the present invention;
[0043] FiG. 26 is illustrates high potential voltage (HiPot) testing of an electroactive polymer actuator enhanced ear bud in accordance with the present invention;
[0044J FIG. 27 shows an electroactive polymer actuator enhanced ear bud made according to the process described in connection with FIG. 26;
[0045] FIGS, 28A-28C illustrate some additional movement strategies such as a piston mode (FIG. 28 A), a bender mode (FIG. 28B) and a basket mode (FIG. 28C) in accordance with the present invention;
[0046] FIGS. 29A and 29B illustrate potential issues arising out of the piston mode movement shown in FIG. 28A;
[0047] FIGS. 30 and 31 illustrate the bender mode previously discussed in connection with FIG. 28B;
[0048] FIG. 32A is an exploded view of a unimorph electroactive polymer actuator including relative dimensions thereof in accordance with the present invention; [0049] FIG. 32B is an assembled view of the unimorph electroaciive polymer actuator shown in FIG. 32A;
[0050] FIG. 33 is an assembled view of several uniraorph electroaciive polymer actuators shown in FIGS. 32A and 32B in accordance with the present invention;
[0051] FIG. 34 is a graphical depiction of measured movement of roll bender
electroaciive polymer actuators;
[0052] FIG. 35A illustrates spring rate on tension roll from loaded hoops in accordance with the present invention;
[0053] FIG. 35B is a graphical depiction of force as a function of stretch ratio; and
[0054] FIG. 36 illustrates a diagram of the human ear.
DETAILED DESCRIPTIO OF THE INVENTION
[0055] Examples of electroaciive polymer devices, their applications, and methods of manufacturing are described, for example, in U.S. Pat. Nos.: 7.394,282; 7,378,783;
7,368,862; 7,362,032; 7,320,457; 7,259,503; 7,233,097; 7,224,106; 7,211,937; 7,199,501; 7,166,953; 7,064,472; 7,062,055; 7,052,594; 7,049,732; 7,034,432; 6,940,221; 6,911,764; 6,891,317; 6,882,086; 6,876,135; 6,812,624; 6,809,462; 6,806,621 ; 6,781,284; 6,768,246; 6,707,236; 6,664,718; 6,628,040; 6,586,859; 6,583,533; 6,545,384; 6,543,110; 6,376,971; 6,343,129; 7,952,261; 7,911,761 ; 7,492,076; 7,761,981 ; 7,521,847; 7,608,989; 7,626,319; 7,915,789; 7,750,532; 7,436,099; 7,199,501 ; 7,521,840; 7,595,580; 7,567,681; 7,595,580; 7,608,989; 7,626,319; 7,750,532; 7,761,981; 7,911,761 ; 7,915,789; 7,952,261; 8,183,739; 8,222,799; 8,248,750, and in U.S. Patent Application Publication Nos.: 2007/0200457;
2007/0230222; 201 1/0128239; 2012/0126959; 2012/0126667; 2012/0206248; 2013/0002587; 2013/0194082; and in PCT Publication Nos.: WO/201 1/097020; WO/2012/099850;
WO/2012/099854; WO/2012/118916; WO/2012/120009; WO/2012/122438;
WO/2012/122440; WO/2012/122440; WO/2012/129357; WO/2012/136503;
WO/2012/148644; WO/2012/156423; WO/2012/173669; WO/2012/175533;
WO/2013/037508; WO/2013/049485; WO/2013/059560; WO/2013/059562;
WO/2013/103470; WO/2013/142552; WO/2013/148641 ; WO/2013/155377;
WO/2013/192143; WO/2014/006005; W /2014/028819; WO/2014/028822;
WO/2014/028825; the entirety of each of which is incorporated herein by reference. [0056| Before explaining the embodiments of the inventi ve eieciroactive polymer based devices in detail, it should be noted that the disclosed embodiments are not limited in application or use to the details of construction and arrangement of parts illustrated in the accompanying drawings and description. The disclosed embodiments may be implemented or incorporated in other embodiments, variations and modifications, and may be practiced or carried out in various ways. Further, unless otherwise indicated, the teens and expressions employed herein have been chosen for the purpose of describing the embodiments for illustrative purposes and for the convenience of the reader and are not intended for the purposes of limiting any of the embodiments to the particular ones disclosed. Further, it should be understood that any one or more of the disclosed embodiments, expressions of embodiments, and examples can be combined with any one or more of the other disclosed embodiments, expressions of embodiments, and examples, without limitation. Thus, the combination of an element disclosed in one embodiment and an element disclosed in another embodiment is considered to be within the scope of the present disclosure and appended claims. 0Θ57] FIGS. 1-4 provide a brief description of eieciroactive polymer structures.
Accordingly, the description now turns to FIGS, 1 A and IB, which illustrate an example of an eieciroactive polymer film or membrane 10 structure. A thin elastomeric dielectric film or layer 12 is sandwiched between compliant or stretchable electrode plates or layers 14 and 16, thereby forming a capacitive structure or film. The length "L" and width "w" of the dielectric layer, as well as that of the composite structure, are much greater than its thickness "t". Preferably, the dielectric layer has a thickness in the range from about 10 μηι to about 100 μηι, with the total thickness of the structure in the range from about 15 μπι to about 10 cm. Additionally, it is desirable to select the elastic modulus, thickness, and/or the geometry of electrodes 14, 16 such that the additional stiffness they contribute to the actuator is generally less than the stiffness of the dielectric layer 12, which has a relatively low modulus of elasticity, i.e., preferably less than about 100 MPa and more preferably less than about 10 MPa, but is likely thicker than each of the electrodes. Electrodes suitable for use with these compliant capacitive structures are those capable of withstanding cyclic strains greater than about 1% without failure due to mechanical fatigue.
[0058] As shown in FIG. IB, when a voltage is applied across the electrodes, the unlike charges in the two electrodes 14, 16 are attracted to each other and these electrostatic attractive forces compress the dielectric film 12 (along the Z-axis). The dielectric film 12 is thereby caused to deflect with a change in electric field. As electrodes 14, 16 are compliant, they change shape with dielectric layer 12. n the context of the present disclosure,
"deflection" refers to any displacement, expansion, contraction, torsion, linear or area strain, or any other deformation of a portion of dielectric film 12. Depending on the architecture, e.g., a frame in which eapacitive structure 10 is employed (collectively referred to as a "transducer"), this deflection may be used to produce mechanical work. Various transducer architectures are disclosed and described in the above-identified patent references,
[0059] With a voltage applied, the transducer film 10 continues to deflect until mechanical forces balance the electrostatic forces driving the deflection. The mechanical forces include elastic restoring forces of the dielectric layer 12, the compliance or stretching of the electrodes 14, 16 and any external resistance provided by a device and/or load coupled to transducer 10. The resultant deflection of the transducer 10 as a result of the applied voltage may also depend on a number of other factors such as the dielectric constant of the
elastornerie material and its size and stiffness. R emo val of the voltage difference and the induced charge causes the reverse effects.
[0060] in some cases, the electrodes 14 and 16 may cover a limited portion of dielectric film 12 relative to the total area of the film. This may be done to prevent electrical breakdown around the edge of the dielectric or achieve customized deflections in certain portions thereof. Dielectric material outside an active area (the latter being a portion of the dielectric material having sufficient el ectrostati c force to enable deflection of that portion) may be caused to act as an external spring force on the active area during deflection. More specifically, material outside the active area may resist or enhance active area deflection by its contraction or expansion.
[0061] The dielectric film 12 may be pre-strained. The pre-strain improves conversion between electrical and mechanical energy, i.e., the pre-strain allows the dielectric film 12 to deflect more and provide greater mechanical work. Pre-strain of a film may be described as the change in dimension in a direction after pre-straining relative to the dimension in that direction before pre-straining. The pre-strain may include elastic deformation of the dielectric film and be formed, for example, by stretching the film in tension and fixing one or more of the edges while stretched. The pre-strain may be imposed at the boundaries of the film or for only a portion of the film and may be implemented by using a rigid frame or by stiffening a portion of the film.
[0062] The transducer structure of FIGS, 1A and IB and other similar compliant structures and the details of their constructs are more fully described in many of the referenced patents and publications disclosed herein.
[0063] FIG. 2A illustrates an exemplary electroactive polymer cartridge 12 having an electroactive polymer transducer film 26 placed between rigid frame 8 where the
electroactive polymer film 26 is exposed in openings of the frame 8. The exposed portion of the film 26 includes three working pairs of thin elastic electrodes 32 on either side of the cartridge 12 where the electrodes 32 sandwich or surround the exposed portion of the film 26. The electroactive polymer film 26 can have any number of configurations. However, in one example, the electroactive polymer film 26 comprises a thin layer of elastomeric dielectric polymer (e.g., made of acrylate, silicone, urethane, thermoplastic elastomer, hydrocarbon rubber, fluoroelastomer, copolymer elastomer, or the like).
[0064] When a voltage difference is applied across the oppositely-charged electrodes 32 of each working pair (i.e., across paired electrodes that are on either side of the film 26), the opposed electrodes attract each other thereby compressing the dielectric polymer layer 26 therebetween. The area between opposed electrodes is considered the active area. As the electrodes are pulled closer together, the dielectric polymer 26 becomes thinner (i.e., the Z- axis component contracts) as it expands in the planar directions (i.e., the X- and Y-axes components expand) (See Figs. IB for axis references). Furthermore, in variations where the electrodes contain conductive particles, like charges distributed across each electrode may cause conductive particles embedded within that electrode to repel one another, thereby contributing to the expansion of the elastic electrodes and dielectric films, in alternate variations, electrodes do not contain conductive particles (e.g., textured sputtered metal films). The dielectric layer 26 is thereby caused to deflect with a change in electric field. As the electrode material is also compliant, the electrode layers change shape along with dielectric layer 26.
[0065] As stated elsewhere herein, deflection refers to any displacement, expansion, contraction, torsion, linear or area strain, or any other deformation of a portion of dielectric layer 26, This deflection may be used to produce mechanical work. As shown, the dielectric layer 26 can also include one or more mechanical output regions or bars 34, The regions or bars 34 can optionally provide attachment points for either an inertial mass (as described below) or for direct coupling to a substrate in the electronic media device.
[0Θ66] In fabricating a transducer, an elastic film 26 can be stretched and held in a pre- strained condition usually by a rigid frame 8. In those variations employing a four-sided frame, the film can be stretched bi -a ial ly. It has been observed that pre-strain improves the dielectric strength of the polymer layer 26. thereby enabling the use of higher electric fields and improving conversion between electrical and mechanical energy, i.e., the pre-strain allows the film to deflect more and provide greater mechanical work. Preferably, the electrode material is applied after pre-straining the polymer layer, but may be applied beforehand. The two electrodes provided on the same side of layer 26, referred to herein as same-side electrode pairs, i.e., electrodes on the top side of dielectric layer 26 and electrodes on a bottom side of dielectric layer 26, can be electrically isolated from each other. The opposed electrodes on the opposite sides of the polymer layer form two sets of working electrode pairs, i.e., electrodes spaced by the electroactive polymer film 26 form one working electrode pair and electrodes surrounding the adjacent exposed electroactive polymer film 26 form another working electrode pair. Each same-side electrode pair can have the same polarity, whereas the polarity of the electrodes of each working electrode pair is opposite each other. Each electrode has an electrical contact portion configured for electrical connection to a voltage source.
[0067] In this variation, the electrodes 32 are connected to a voltage source via a flex connector 30 ha ving leads 22, 24 that can be connected to the opposing poles of the voltage source. The cartridge 12 also includes conductive vias 18, 20. The conductive vias 18, 2(1 can provide a means to electrically couple the electrodes 8 with a respective lead 22 or 24 depending upon the polarity of the electrodes.
[0068] The cartridge 12 illustrated in FIG. 2A shows a 3-bar actuator configuration.
However, the devices and processes described herein are not limited to any particular configuration, unless specifically claimed. Preferably, the number of the bars 34 depends on the active area desired for the intended application. The total amount of active area, e.g., the total amount of area between electrodes, can be varied depending on the mass that the actuator is trying to move and the desired frequency of movement, in one example, selection of the number of bars is determined by first assessing the size of the object to be moved, and then the mass of the object is determined. The actuator design is then obtained by configuring a design that will move that object at the desired frequency range. Clearly, any number of actuator designs is within the scope of the disclosure,
[0069] An electroactive polymer actuator for use in the processes and devices described herein can then be formed in a number of different ways. For example, the electroactive polymer can be formed by stacking a number of cartridges 12 together, having a single cartridge with multiple layers, or having multiple cartridges with multiple layers.
Manufacturing and yield considerations may favor stacking single cartridges together to form the electroactive polymer actuator. In doing so, electrical connectivity between cartridges can be maintained by electrically coupling the vias 18, 20 together so that adjacent cartridges are coupled to the same voltage source or power supply.
[0070] The cartridge 12 shown in FIG. 2A includes three pairs of electrodes 32 separated by a single dielectric layer 26, in one variation, as shown in FIG. 2B, two or more cartridges 12 are stacked together to form an electroactive actuator 14 that is coupled to an inertial mass 50. Alternatively, the electroactive actuator 14 can be coupled directly to the electronic media device through an intermediary attachment plate or frame. As discussed below, the electroactive actuator 14 may be placed within a cavity 52 that allows for movement of the actuator as desired. The pocket 52 may be directly formed in a housing of a case.
Alternatively, pocket 52 may be formed in a separate case 56 positioned within the housing of the device. If the latter, the material properties of the separate case 56 may be selected based upon the needs of the actuator 14. For example, if the main body of the housing assembly is flexible, the separate case 56 can be made rigid to provide protection to the electroactive actuator and/or the mass SO. In any event, variations of the device and processes described herein include size of the cavity 52 with sufficient clearance to allow movement of the actuator 14 and/or mass 50 but a close enough tolerance so that the cavity 52 barrier (e.g., the housing or separate case 56) serves as a limit to prevent excessive movement of the electroactive actuator 14. Such a feature prevents the active areas of the actuator 14 from excessive displacement that can shorten the life of the actuator or otherwise damage the actuator.
[0071] FIGS. 3-4 provide a description of an electroactive polymer based module suitable for use in the devices such as headphones. FIG. 3 is a partial cutaway view of an
electroactive polymer system that may be integrally incorporated to provide motion effects, Accordingly, in one embodiment the system comprises an electroactive polymer module 200. An electroactive polymer actuator 222 is configured to slide an output plate 202 (e.g., sliding surface) relative to a fixed plate 204 (e.g., fixed surface) when energized by a voltage "V." The plates 202, 204 are separated by steel balls, and have features that constrain movement to the desired direction, limit travel, and withstand drop tests. For integration into headphones, the top plate 202 may be attached to an inertial mass.
[0072] Segmenting the electroactive polymer actuator 222 within a given footprint into (n) sections is a convenient method for setting the passive stiffness and blocked force of the electroactive polymer system. A pre-stretched dielectric is held in place by the rigid material that defines an external frame such as the fixed plate 204 and one or more windows within the frame. Inside each window is an output bar 212 of the same rigid frame material, and on one or both sides of the output bar 212 are electrodes 208. Alternatively, an adhesive may replace the rigid frame material as disclosed in co-assigned PCT Publication No.
WO/2012/099854; the entire disclosure of which is hereby incorporated by reference.
[0073] Applying the potential difference (V) across the dielectric on one side of the output bar 212 creates electrostatic pressure in the elastomer which causes the electrode area to expand and exert force on the output bar 212. This force scales with the effective cross section of the electroactive polymer actuator 222, and therefore increases linearly with the number of segments, each of which adds to the effective width of the actuator. The passive spring rate scales with n2, as each additional segment effectively stiffens the device twice, first by shortening it in the stretching direction (X) and second by adding to the width (Y) that resists displacement. Both spring rate and blocked force scale linearly with the number of dielectric layers (m).
[0074 j Among the advantages of electroactive polymer modules 200 is the ability to generate low frequency vibrations inside the ear cup housings that can be felt substantially
immediately by the user. In addition, electroactive polymer modules 200 consume low power, and are well suited for customizable design and performance options. The electroactive polymer module 200 is representative of electroactive polymer modules developed by Artificial Muscle, inc., of Sunnyvale, CA, USA.
[0075] Still with reference to FIG. 3, many of the design variables of the electroactive polymer module 200, (e.g., thickness, footprint) may be fixed by the needs of module integrators while other variables (e.g., number of dielectric layers, operating voltage) may be constrained by cost. Because actuator geometr - the allocation of footprint to rigid supporting structure versus active dielectric - does not impact cost much, it may be a reasonable way to tailor performance of the eiectroactive polymer module 200 to an application where the module 200 is integrated with headphones or other device,
[0076] Computer implemented modeling techniques can be employed to gauge the merits of different actuator geometries, such as: (1) Mechanics of the Handset/User System; (2) Actuator Performance; and (3) User Sensation. Together, these three components provide a computer-implemented process for estimating the capability of candidate designs and using the estimated capability data to select an eiectroactive polymer design suitable for mass production. The model predicts the capability for two kinds of effects: long effects (e.g. gaming and music), and short effects (e.g. key clicks). "Capability" is defined herein as the maximum sensation a module can produce in service. Such computer-implemented processes for estimating the capability of candidate designs are described in more detail in commonly assigned PCT Publication No, WO/2011/102898, the entire disclosure of which is hereby incorporated by reference.
[0077] FIG . 4 is a schematic diagram of an eiectroactive polymer system 300 designed to illustrate the principle of operation of eiectroactive polymer modules. The eiectroactive polymer system 300 comprises a power source 302, shown as a low voltage direct current (DC) battery for illustrative purposes, electrically coupled to an eiectroactive polymer module 304. In accordance with the present disclosure, the power source (Vsatt) represents the output of an audio signal source configured to generate low frequency audio signals below about 200 Hz, for example, and in one embodiment between about 2 Hz to about 200 Hz, where the term "about" stands for ±10%. The eiectroactive polymer module 304 comprises a thin elastomeric dielectric element 306 disposed (e.g., sandwiched) between two conductive electrodes 308A, 308B. The conductive electrodes 3Θ8Α, 308B are stretchable (e.g., conformable) and may be printed on the top and bottom portions of the elastomeric dielectric element 306 using any suitable technique, such as, for example screen printing.
[0078] The eiectroactive polymer module 304 is activated by coupling the battery 302 (e.g., signal source) to an actuator circuit 310 by closing a switch 312, The actuator circuit 310 converts the low DC voltage Vsatt signal into a higher DC voltage \7 iR signal suitable for driving the eiectroactive polymer module 304. In accordance with the present disclosure, an additional circuit may be located within the opening 124 defined by the housing 118, where the circuit is configured to convert the low voltage low frequency audio signal from the audio signal source, to a higher voltage signal suitable for driving the electroactive polymer actuator 122 as shown in FIGS, 1 A-1B,
[0079] Returning to FIG. 4, when the voltage Vin is applied to the conductive electrodes 308A, 308B the elastomeric dielectric element 306 contracts in the vertical direction (V) and expands in the horizontal direction (H) under electrostatic pressure. The contraction and expansion of the elastomeric dielectric element 306 can be harnessed as motion. The amount of motion or displacement is proportional to the input voltage Vin. The motion or
displacement may be amplified by a suitable configuration of electroactive polymer actuators.
[0080J The following description is directed to independent tuning of amplitude and frequency of motion and volume levels for headphones, FIG. 5 is an exploded side view of an electroactive polymer device 400 comprising independent tuning of motion and volume levels for each channel in accordance with present invention. As shown in FIG. 5, the electroactive polymer device is shown in the form of a headphone. The electroactive polymer device 400 comprises a headband 402 and first and second ear cushions 404i, 4042, first and second speakers 406i5 4062, first and second drive electronics 408i, 4082, first and second electroactive polymer actuators 410i, 4102, and first and second ear cups 412i, 4122. The "first" components correspond to a first channel of the electroactive polymer device 400 and the "second" components correspond to the second channel of the electroactive polymer device 400.
[0081] FIG. 6 is a level control switch 420 for independent control of volume and motion levels for each channel of the audio device 400 shown in FIG. 5. The level control switch 420 comprises four separate switches 422s, 4222, 424i, 4242, to control left speaker 406i volume, right speaker 4062 volume, left electroactive polymer actuator 410i. and right electroactive polymer actuator 4ΙΘ2, respectively.
[0082] With reference to both FIGS. 5 and 6, the level control switch 420 provides independent control of motion from the electroactive polymer actuators 410i, 41( and sound volume from the speakers 406i, 062 for the electroactive polymer device 400. The level control switch 420 comprises a first volume control switch 422i to control the volume level of the first speaker 4061 and a second volume control switch 4222 to control the volume level of the second speaker 4062 independently. The level control switch 420 also comprises a first vibration control switch 424i to control the motion level of the first electroactive polymer actuators 410i and a second vibration control switch 4242 to control the motion level of the second eleetroactive polymer actuators 4102 independently.
[0083] Accordingly, the present invention allows custom and independent tuning of the motions produced by the eleetroactive polymer actuators 410i, 4102 and the sound volume and content produced by the speakers 406s, 4062 for each side of the eleetroactive polymer device 400. As shown in FIG, 6, for example, using the i to 10 level control switch 422i the user could tune the sound volume level of the first speaker 4061 to 6 and using the 1 to 10 level control switch 424i the user could tune the motion level of the first eleetroactive polymer actuator 410i to 8 on the first side (e.g., right side). At the same, using the 1 to 10 level control switch 4222 the user could tune the sound volume level of the second speaker 4062 to 4 and using the 1 to 10 level control switch 4242 the user could tune the motion level of the second eleetroactive polymer actuator 4102 to 3 on the second side (e.g., left side).
[0084] The combination of independent volume and motion tuning control can be advantageous for individuals that are hard of hearing because the technology allows someone to feel their music including frequencies that a person may not be able to hear. Furthermore, being able to independently tune the eleetroactive polymer actuators 41θι, 4102 is advantageous because users may have asymmetric hearing loss. For example, someone with hearing loss may have 80% hearing loss in the right ear and have only 60% hearing loss in the left ear. Thus, someone with that profile may want to turn up the volume level as well as the eleetroactive polymer actuator level on the right side but turn down the volume level and the eleetroactive polymer actuator level on the left side, relative to the right side. Even if an individual does not have hearing loss, they may prefer to experience different levels of motion by the eleetroactive polymer actuator (conductive audio response) on one ear versus the other.
[0085] It will be appreciated that the level control switch 420 mechanism for the
eleetroactive polymer device 400 speaker volume level as well as eleetroactive polymer actuator level may be integrated either directly into the eleetroactive polymer device 400 ear cups 412j, 4122 or as a separate wired or wireless controller.
[0086] The following description is directed to relaxation headphones including eleetroactive polymer actuators. Low frequency phenomena may induce improved states of relaxation (see, ΡΗΟΊΌ80ΝΙΧ and ILiGHTZ products as examples). Thus, coupling low frequency vibrations or sounds to the human body may better help people to relax. Some methods use large chairs or apparatus which is not easily moved or easily transported. Other techniques use standard headphones and sound waves in an attempt to provide a transportable relaxation apparatus. Because conventional headphones do not directly produce sound waves at the frequencies of interest, most acoustic methods use frequency differences of fairly high frequencies, for example 400 Hz and 405 Hz, to obtain a 5 Hz difference. In addition, a sonic audio response due to sound waves may not be as effective at coupling into a human body as a conductive audio response which can be transmitted by the skeletal system.
[0087] FIG. 7 is an exploded view of a device 430 comprising an electroactive polymer actuator 432 in accordance with the present invention. FIG. 8 is a cross-sectional view of the audio device 430 shown in FIG. 7 in accordance with the present, invention. With reference now to both FIGS. 7 and 8, the audio device 430 comprises an electroactive polymer actuator 432 attached to an exterior portion of a sound cavity cover 436. A speaker 438 is located within the cavity defined by the sound cavity cover 436. A speaker housing 440 is rigidly attached to an ear cup housing 434 and supports the speaker 438, the sound cavity cover 436, and the electroactive polymer actuator 432 therebetween. A cushion 442 may be attached to the speaker housing 440.
[0088] Still with reference to both FIGS, 7 and 8, there are many different device (e.g., headphone) architectures including over-the-ear (circum aural) and on-the-ear (supra-aural) configurations. In addition, the acoustic cavity may be: (1) open; (2) closed; or (3) closed with an acoustic port. The electroactive polymer actuator 432 (e.g., electroactive polymer motion element or module) can be used in over-ear and on-ear headphones to improve the user experience by enhancing the low frequency content of the aud o. Preferably, the electroactive polymer actuator 432 is coupled directly to the sound cavity cover 436 portion of the audio device 430, which is rigidly attached to the speaker housing 440 and the cushion 442. As shown, the surface outside of the sound cavity cover 436, behind the speaker 438, may be utilized to mount the electroactive polymer actuator 432.
[0089] The electroactive polymer actuator 432 may be integrated in over-the-ear and on-the- ear headphones to improve the user experience by enhancing the low frequency content of the audio being played. The electroactive polymer actuator 432 may preferably be attached to a rigid flat surface, such as the back of the sound cavity cover 436, on one side and to a suspended mass on the other side. The electroactive polymer actuator 432 moves the mass relative to the speaker housing 440. according to the low frequency portion of the audio signals it receives. A suspended mass attached to the speaker housing 440 through the electroaciive polymer actuator 432 results in a mass-spring-damper system. The movement direction of the electroaciive polymer actuator 432 may be best when oriented in parallel plan relative to the ear, orthogonal to the axis of the acoustic driver (to minimize acoustic artifacts).
[0990] Accordingly, the electroactive polymer device depicted in FIGS. 7 and 8 may be employed to create binaural frequencies that humans may feel. The created effect influences the theta brainwaves of humans inducing the brain to enter a state of deep relaxation.
[00913 As illustrated in FIG S. 7 and 8, the device 430 includes a pair of headphones in which a pair of electroactive polymer actuators 432 has been mounted. An inertial mass of about 26 g rnay be added to each of the electroactive polymer actuators 432 to produce soothing motion (vibration) phenomena in the headphones 430. Stereo electronics, discussed below in connection with FIGS. 9-1 1, provide for full independent left and right side motion
(vibration) and left and right side sound level control, as discussed above in connection with FIGS. 4 and 5, to provide the relaxing experience to the user.
[0092] Lower mechanical resonant, frequencies are used as compared to headphones optimized for music listening. For example, in one embodiment, the resonant frequency was selected around 44 Hz, even though lower frequencies are achievable.
[0093] As discussed above, most other methods of adding vibration use eccentric rotating masses attached to electric motors which cannot be controlled over a wide arbitrary range of frequencies and amplitude. Such techniques are not dynamic and result in monotonic motion centered around a single frequency. The electroactive polymer actuators 432 are dynamic and can be controlled to a wide variety of sensations and effects. With electroactive polymer actuators 432, the device 430 may generate frequencies that cannot be heard but be felt by humans to influence the theta brainwaves. Relaxation experts may be able to design better programs using such an electroactive polymer actuator 432 enabled low-frequency device 430. Humans may enter a relaxation state for their body and brain on a button press and using a mobile device.
[0094] It should be understood that although the discussion above centers on the application of low-frequency stimuli to induce a relaxation state for the user, the present invention may also be used with drive signals designed to provide stimulation or increased alertness in the user and more generally to provide stress relief for the user.
[0095] Most audio content can be delivered as a two-channel, real-time analog signal such as stereo music, for example. In other instances, the audio content may be delivered as streaming digital information. The analog audio signals may be processed to extract meaningful content. This real-time content may be directed to the electroactive polymer actuators 432 to produce compelling motion/acoustic effects.
[0096] FIGS. 9-1 1 describe an electronics system design that may be employed to operate the electroactive polymer devices 400. 430 described in connection with FIGS. 4-8. As to each device 400, 430, the electronics system may require a unique implementation based on its features and specific design, therefore the electronics system described herein is generic.
[0097] Accordingly, turning now to FIG. 9, there is shown a diagram of a electroactive polymer /acoustic audio device 500 in accordance with one embodiment of the present invention. Preferably, the audio source 502 delivers audio content as two two-channel realtime analog signals. In other instances, the audio source 502 may deliver streaming digital information. The audio source 502 includes any one of a PC, IPOD, IPHONE, USB, 3.5 mm, stereo, among other audio sources 502. The audio source 502 outputs a one or two channel acoustic signal 504 and a one or two channel motion signal 506. The acoustic and motion signals 504, 506 are processed to extract meaningful content. The acoustic signal 504 is processed by acoustic electronic system 508 and the motion signal 506 is processed by an act uator electronic system 514. The user may provide input 526 in any of the audio source 502, the acoustic electronic system 508, or the actuator electronic system 514.
[0098] The acoustic electronic system 508 may comprise relatively simple audio electronics or more sophisticated digital signal processing (DSP) electronic circuits. In some
embodiments, the acoustic electronic system 508 may comprise passive or active noise canceling circuits. The acoustic electronic system 508 includes a left channel output section SIOi and a right channel output section 5102 to independently drive left and right speakers 512i, 5122, respectively. Thus, the left and right speakers 512», 5122 produce stereo sound with independent volume level control. In one embodiment, however, one output signal may be used to drive both speakers 512i, 5122 at once. Both amplitude and frequency of the low voltage electrical signals output from the left channel output section 510i and the right channel output section 51 2 are independently tunable. [0099] The motion signal 506 is processed by the actuator electronic system 514 to extract meaningful content. The actuator electronic system 514 comprises a signal processing section 522 and a high voltage amplifier section 524. The signal processing section 522 receives the motion signal 506 from the audio source 502 and prepares the signal for feeding into the high voltage amplifier section 524. The high voltage amplifier section 524 includes a left channel output section Si 6i and a right channel outpu section 51 2 to independently drive left and right electroactive polymer actuators 518s, SI82, respectively, in the direction indicated by arrows 520i, 5202, respectively. The real-time motion signal 506 is thus directed to the electroactive polymer actuators 518i, 5182 to produce compelling motion effects. In one embodiment, however, one output signal may be used to drive both electroactive polymer actuators 518i, 5182 at once. Both amplitude and frequency of the high voltage electrical signals output from the left channel output section 5161 and the right channel output section 5I62 are independently tunable.
[0100] FIG. 10 is a block diagram 600 of an electronic topology for an independently tunable actuator electronic system in accordance with the present invention, The actuator electronic system 600 is suitable for independently driving electroactive polymer actuators, such as the electroactive polymer actuators 518j, SiSi described in connection with FIG. 9. As shown in FIG. 10, the block diagram 600 of the electronic circuit for generating low frequency motion signals 614L, 614R for driving the electroactive polymer actuators 616L, 616R, respectively, A variety of signal conditioning, amplifying, compensating, and driving circuits are also implemented, in particular, an analog audio signal module 602 receives analog motion signals from a differential amplifier source, or any suitable source. In one embodiment, the differential amplifier may be implemented with any suitable integrated circuit amplifier.
[01011 From the analog audio signal module 602, the signal is passed to a low frequency digital filter module 606, The low frequency digital filter module 606 may be implemented using any suitable circuit technique and may comprise a microcontroller and a programmable gate array circuit, among other digital or analog processing circuit elements. In one embodiment, the low frequency digital filter module 606 may be implemented with any suitable programmable system, such as, for example a programmable system-on-chip controller.
[0102] A low frequency amplifier module 608 amplifies the output of the low frequency digital filter 6Θ6 and the output is passed to the programmable gate array circuit. In one embodiment, the low frequency amplifier module 608 may be implemented using any- suitable integrated circuit amplifier.
[0103] The output of the low frequency digital filter 606 is provided to a non-linear in verse transform circuit (square root circuit) such as an inverse polynomial circuit 610, which provides the electronic audio signal compensation to remove unwanted distortions in the audio signal used to move the electroactive polymer actuators. In other words, the inverse polynomial circuit 610 approximates an inverse function to linearize the electroactive polymer actuators, for example. In various embodiments, the inverse polynomial circuit 610 may be implemented using integrated circuits, programmable circuits, piecewise linear circuits and/or any combinations thereof. In one embodiment a piecewise linear circuit can be used to approximate a non-linear function, such as sine, square-root, logarithmic, exponential, and the like, for example. The quality of the approximation depends on the number of segments employed by the piecewise linear circuit and the strategy used in determining the segments. There are two approaches to building piecewise linear circuits: (1) non-linear voltage dividers with diodes (or transistors) used to switch between the segments and (2) summing the outputs of a chain of saturating amplifiers. Both of these approaches may be employed and are technically equivalent although each has its advantages and disadvantages.
[0104] The diode approach has the advantage of simplicity but the disadvantages Include temperature dependence on the switching thresholds and relatively slow response. The saturating amplifier method has the disadvantage of complexity but the advantages of minimal temperature dependence on thresholds and high speed, In various embodiments, the inverse polynomial circuit 610 ma be implemented as a compression or an expansion circuit, each type having a different circuit topology, A compression circuit compresses the dynamic range of an input signal whereas an expansion circuit expands the dynamic range. Examples of compression circuits include square-root, logarithmic, and sine and generally employ nonlinear voltage divider techniques. One example of an expansion circuit is an exponential function.
[0105] In other embodiments, a combination of compression and expansion circuits may be employed to implement the inverse polynomial circuit 610 to linearize electroactive polymer actuators, for example. One embodiment of a piece wise linear circuit using diode switching to approximate an inverse square-root function may be employed. The output of the inverse -?2- polynomial circuit 610 is provided to a high voltage power amplifier 612 for amplification to a level sufficient to drive the electroactive polymer actuator module. Preferably, the voltage required to drive the electroactive polymer actuator module may range from a few hundred volts (V) to several thousand volts fkV), with a nominal driving voltage of about 1 kV. A left channel output 614L of the high voltage amplifier 612 is provided to a left reflex actuator and mass 6.16L, e.g., to an electroactive polymer actuator located in a left ear cup of the
headphones. A right channel output 6I4R of the high voltage amplifier 612 is provided to a right reflex actuator and mass 61611, e.g., to an electroactive polymer actuator located in a right ear cup of the headphones. In one embodiment, single phase actuators can be improved using a square root circuit in the sensory enhanced headphones comprising electroactive polymer actuators. Non-linear control techniques also may be employed in multi-phase actuators, for example.
[0.106] Accordingly, as described in connection with FIGS. 5-10, in one embodiment of the present invention provides an apparatus for applying binaural frequencies that a human can feel. For example, if a person is in beta stage (highly alert) and a stimulus of 1GHz is applied to his/her brain for some time, the brain frequency is likely to change towards the applied stimulus. The effect will feel relaxing to the person; a phenomenon known as "frequency following response."
[0107] Electroactive polymer actuators and driving techniques described in connection with FIGS. 5-1.0 may be used to generate motion signals to stimulate the brain using a binaural technique. The stimulus may be applied using binaural beats. If the left element is presented with a steady tone of 500Hz and the right element a steady tone of 510Hz, these two tones combine in the brain. The difference, 10Hz, is perceived by the brain and is a very effective stimulus for brainwave entrainment. This lOHz is formed entirely by the brain. The devices described in connection with FIGS. 5-10 mat be employed to move one side of a person's head with a first motion signal at a first frequency (fi) and the other side of the person's head with a second motion signal at a second frequency ( ¾. The left and right motion signals do not mix together, but rather constructively interfere to create a binaural beat with a frequency roughly equal to the frequency difference (Δ/' fi - fi) which is perceived by brain. .
[0108] For example, to obtain a motion stimulus of 10Hz, motion signals of 50Hz and 60Hz, or 40Hz and 50 Hz, or 80Hz and 90Hz should be applied. The electronic system 600 described in FIG. 10 is configured to respond to signals between ~THz and ~150Hz. The eiectroactive polymer actuators have a mechanical resonance around 44 Hz when placed on a human subject. Optimum frequencies are in approximately the 20 Hz to 80 Hz range,
[01Θ9] it will be appreciated that the motion level in each channel can be independently controlled to customize the binaural effect using electroactive polymer actuators, in one embodiment, where the devices have independently controlled acoustic and motion levels, the binaural stimulus may be enhanced using a combination of audible frequencies and motion frequencies to generate binaural stimulus to the brain. Table 1 below depicts the effect of binaural beats.
[0110] TABLE 1
Figure imgf000025_0001
[0111] FIGS. 11-14 are graphical depiction of test results conducted with a modified ATH- M50 Headphones. The headphones included three bar/two layer actuators installed into flexure modules using a 26 g inertial mass, as described by way of example in FIGS. 2 A and 2B. Only one bar of three was connected to the mass which reduced the spring constant by a factor of three. This resulted in a significantly lower mechanical resonant irequency than the typical headphones used for audio enhancement. The acoustic volume levels and actuator motion levels may be operated independently or together as described in connected with FIGS. 5-10, This is a full stereo system with independent gains on both actuators. At minimum gain setting, 100 mV peak-to-peak ("pk-pk") produces full output to the actuators. At maximum gain setting, 25 mV pk-pk produces full output to the actuators. A quick check of the acoustic response after modification shows no significant differences from a standard ATH-M50 headphone, A chirp frequency response from 20 Hz-20 kHz is shown below. The test signal is 200 mV pk-pk and a logarithmic sweep occurring in one second. [0112] FIG. 1 1 is a graphical depiction 700 of acoustic response of a headphone with electroactive polymer actuators turned on. Frequency (Hz) is shown along the horizontal axis on a logarithmic scale and Acoustic Response |y(t)| is shown along the vertical axis.
[0113] FIG. 12 is a graphical depiction 710 of acoustic response of the headphones with electroactive actuators in FIG. 1 1 turned on and actuator gains set to minimum. Frequency (Hz) is shown along the horizontal axis on a logarithmic scale and Acoustic Response jy(f)| is shown along the vertical axis.
[0114] FIG. 13 is a graphical depiction 720 of acceleration of headphone ear c ps versus frequency measured on a Head And Torso Simulator (HATS). Frequency (Hz) is shown along the horizontal axis on a logarithmic scale and Acceleration (g) is shown along the vertical axis. The resonant frequency measured on HATS (B&K 4128c Head and Torso Simulator) was about 53 Hz but measures around 44 Hz when placed on a human test subject (see FIG. 14). The vertical scaling on FIG. 13 is 0.0312 was 0.1 g peak (0.2 g's peak-to-peak). Left and right vertical (Y) axis and horizontal (X) axis acceleration was measured versus vibration frequency of the electroactive polymer actuator. As shown in FIG. 12, four curves were plotted: the left X-axis 726, the left Y-axis 722, the right X-axis 728, and the right Y- axis 724. Because the electroactive polymer actuators were configured to move primarily In the X-direction relative to the Y-direction, as shown in FIG. 12, the right X-axis and the left X-axis 726 accelerations were greater than the corresponding right Y-axis 724 and left Y-axis 722 accelerations.
[0115] F IG. 14 is a graphical depiction 730 of acceleration of headphone ear cups comprising electroactive polymer actuators versus frequency measured on a human test. Frequency (Hz) is shown along the horizontal axis on a logarithmic scale and Acceleration (g) is shown along the vertical axis. The resonant frequency measured is about 44 Hz when placed on a human test subject. The vertical scaling on FIG. 13 is 0.0312 is 0.1 g peak (0.2 g's peak-to-peak). As shown in FIG. 13, four curves are plotted: the left X-axis 736, the left Y-axis 732, the right X-axis 738, and the right Y-axis 734, Because the electroactive polymer actuators were configured to move primarily in the X-direction relative to the Y-direction, as shown in FIG. 12, the right X-axis and the left X-axis 726 accelerations were greater than the corresponding right Y-axis 724 and left Y-axis 722 accelerations,
[0116] The following description of the present invention is directed to integration of an electroactive polymer actuator into an ear bud insert of an earphone. The assembly safely shields the electroactive polymer actuator and high voltage wires to minimize the risk of shock. FIGS. 5-17 illustrate three approaches to conforming an integrated electroactive polymer actuator/ear bud into an ear.
[0117] FIG. 15 is a cross-sectional view of a hub-mounted audio device 800 located inside the ear canaS 80S in accordance with one embodiment of the present invention. The hub- mounted audio device 800 comprises a wall 806 and a potted electroactive polymer actuator 804 mounted about a hub 802. As shown in FIG. 15, an inner portion 810 of the potted electroactive polymer actuator 804 contacts an outer surface 812 abut the perimeter of the hub 802 and outer portions 814 of the electroactive polymer actuator 804 contact inner portions of the wall 806 whereas other surfaces 816, 817 of the electroactive polymer actuator 804 do not contact the wall 806 and rather define openings 818, 819 between the wall 806 and the outer surfaces 816, 817. The openings 818, 819 are separated by the hub 802 and potted electroactive polymer 804.
[0118] FIG. 16 is a cross-sectional view of a wall-mounted audio device 820 located inside the ear canal 808 in accordance with one embodiment of the present invention. The wall- mounted audio device 820 comprises a wall 826 and a potted electroactive polymer actuator 824 mounted to the wall 826 rather than a hub 822. As shown in FIG. 16, an outer surface 828 of the potted electroactive polymer 824 contacts an inner portion of the wall 826 about the perimeter thereof. Portions 830 on an inner surface of the potted electroactive polymer 824 contact the hub 822 and defines openings 832, 834 between portions 836, 838 of the potted electroactive polymer actuator 824 and outer surfaces of the hub 822.
[0119] FIG. 1 7 is a cross-sectional view of a fully potted audio device 840 located inside the ear canal 808 in accordance with one embodiment of the present invention. The fully potted audio device 840 comprises a hub 842, a potted electroactive polymer actuator 844, and a wall 846. The potted electroactive polymer actuator 844 occupies the entire space between the inner surface 848 of the wall 846 and the outer surface 852 of the hub 842. Accordingly, the outer surface 850 of the potted electroactive polymer actuator 844 is in contact with the inner surface 848 of the wall 846 and the inner surface 854 of the potted electroactive polymer actuator 844 is in contact with the outer surface 852 of the hub 842.
[0120] FIG. 18 is a diagram of a conventional earphone 860. The conventional earphone 860 includes a rigid case back 862, a rigid case front 864, and a flexible rubber ear bud 866. A rigid sound tube 868 is molded into the rigid case front 864. The conventional earphone 860 is built using two pieces, with the rigid sound tube 868 rigidly attached to the rigid front case 864 of the earphone 860.
[0121] FIG. 19 is a diagram of an earphone 870 in accordance with the present invention. The earphone 870 comprises a rigid case back 872, a rigid case front 874, and a flexible rubber ear bud 876. In accordance with this embodiment of the present invention, however, a rigid sound tube 878 is formed as an integral feature of the otherwise flexible rubber ear bud 876. During assembly, the end 884 of the sound tube 878 is attached to the rigid case front 874, for example using adhesive, snap-fit, or ultrasonic welding. This provides a
straightforward means of routing high-voltage leads 880 (1 (V · ), 882 (GND) into the case front 874 and case back 872 during assembly.
[0122] Accordingly, the new configuration of the earphone 870 described in FIG. 19 decouples the rigid sound tube 878 from the rigid front case 874 of the earphone 870 to accommodate an electroactive polymer actuator and accompanying high voltage leads 880, 882. This embodiment of the present invention integrates the di electric elastomer actuator into the ear bud 876 insert portion of the earphone 870 as described in connection with FIGS. 15-17. The assembly safely shields the electroactive polymer actuator and the high voltage wires 880, 882 to minimize the risk of shock,
[0123] As shown in FIG. 19, the high voltage wires 880, 882 are routed inside the protective rigid case front 872 at the eariiest possible point, minimizing shock hazard. Furthermore, the earphone 870 provides a rigid foundation for building up the flexible ear bud 876, enabling better precision when molding in or otherwise integrating the electroactive polymer actuator into the ear hud 876, as discussed in connection with FIGS, 15-17. Finally, the earphone 870 configuration shown in FIG. 19 enables the designers to control space that was previously taken up by the rigid "sound tube" of the rigi d case front and the "hub" of the flexible ear bud. As space is at a premium in the ear canal it is helpful to be able to minimize the radial thickness of these passive parts, and leave more room for the electroactive polymer actuator.
[0124] FIGS. 20A-20D illustrate placement of electroactive polymer actuator 890 in an ear bud 876 in accordance with the present invention. The ear bud 876 is coupled to the rigid front case 874. The high-voltage wires 880, 882 are electrical ly coupled to the electroactive polymer 890 and in FIGS. 20A, 20B are seen exiting the end of the rigid front case 874. As shown in FIG. 20D, the electroactive polymer 890 are located within a cavity 892 formed inside the flexible ear bud 876, As shown in FIG. 20D, the electroactive polymer 890 are in contact with the wall of the ear bud 876 but not the hub 892.
[0125] FIG. 21 is a graphical depiction of frequency response of the ear bud 876 shown in FIGS. 20A-20D in accordance with the present invention. The acoustic response was adequate. The tactile response was low when held in fingertips, there was no sensation at · !' 20-100 Hz and were detectable at ~f=T 00-200 Hz, Future configurations inspired by these results include addition of strain relief at soft-stiff transition - Soft = ear bud 876 and electroactive polymer actuator 890; Stiff - wire-wrap leads 880, 882. For measurements, a cast silicone ear and canal was considered ideal as it would match body stiffness: (Shore 00 35). An LDM laser was shined through the silicone to measure movement of a laser dot on the ear bud surface. The LDM laser was moved to get multiple points.
[0126] For electrical insulation, zero-defect isolation of .8 kV is required and the insulation must not over-constrain movement. Because the ear bud 876 surface has compound curvature, it requires precise molds and fixtures. Other desirable methods of manufacturing the ear bud 876 include machining or 3D printing,
[0127] FIG. 22 illustrates an impro ved potting fixture 900 for placing the electroactive polymer actuator 890 into ear buds 876 in accordance with the present invention. As shown, the electroactive polymer 876 and the high voltage wires 880, 882 located through various openi ngs 902 formed on a cover portion of the potting fixture 900. The ear buds 876 are aligned along corresponding receiving holes 906 formed in a bottom case portion 908 of the potting fixture 900. As shown in FIG. 22, the electroactive polymer 890 electrically coupled to the high voltage wires 880. 882 are inserted into openings 910 formed in the ear buds 876 and the entire assembly is then inserted into receiving holes 906 in the bottom case 908 where the assembly is potted,
[0128] FIGS. 23A-23D are photographs showing an electroactive polymer actuator 890 placement in an ear bud 876 in accordance with the present invention. In FIG. 23 A, the electroactive polymer actuator 890 electrically coupled to high-voltage wires 880, 882 is sho wn to the left of a secti oned portion of the ear bud 876. A detail view of the sectioned ear bud 876 is shown in FIG. 23C. FIGS. 23B and 231) show sectional views of the electroactive polymer actuator 890 mounted inside the ear bud 876, [0129] FIG. 24 is a graphical depiction of a finite element analysis rough draft model prediction of movement of the electroactive polymer actuator 890 within the ear bud 876.
[0130] FIG. 25 A is a graphical depiction 920 of measured movement consistent, with the prediction shown in FIG. 24 in accordance with the present invention. F G. 25B is a sectional vie w of the ear bud 876 and the electroactive polymer actuator 890 mounted therein in accordance with the present invention. A medium ear bud 876 with a 20 layer
electroactive polymer actuator 890, one slab, potted in a potting compound, 1.8 kV, free stroke was used to generate the data for FIG. 25A. The angle Θ was varied from -5 degrees to 60 degrees and the measurements plotted in the graph 920 shown in FIG. 25A were taken at - 5 degrees, 10 degrees, 30 degrees, and 60 degrees. With reference to both FIGS. 25 A and 25B, the solid triangles (A) represent 60 degrees; the solid circles (·) represent 30 degrees; the solid squares (ss) represent 10 degrees; and the solid diamonds ( ) represent -5 degrees. The amplitude distribution was consistent with finite element rough draft shown in FIG. 24. The direction also agreed (field on radius reduced), whereas the peak amplitude was lower than the model.
[Θ131] FIG. 26 is a photograph depi cting the results of high potential voltage (HiPot) testing of an electroactive polymer actuator enhanced ear bud in accordance with the present invention. The procedure is as follows: contact with Al foil 922; repeat 5x to ensure all surface tested. Vol.tage=3600 DC (2x operating voltage). Time =1000 sec. No failures (N=2 samples). A device made in this manner is illustrated in FIG. 27 and had V ) .6kV (35 V/μτη), a frequency=60-120 Hz. The tactile sensation was detected in pinch grip (3/3 subjects). A tactile sensation was detected in the ear canal (3/3 subjects) and was reported to be not annoying (3/3).
[0132] FIGS. 28A-28C illustrate some additional movement strategies such as a piston mode (FIG. 28A), a bender mode (FIG. 28B) and a basket mode (FIG. 28C) in accordance with the present invention. As shown in FIG. 28 A, in piston mode the motion is along the
longitudinal axis defined by the electroactive polymer actuator 930. As shown in FIG. 28A, excitation by a voltage potential causes electroactive polymer actuator 930 to elongate by Ad in the longitudinal direction defined by the electroactive polymer actuator 930, In FIG. 28B, in bender mode the electroactive polymer actuator 932 bends under a force F like a beam for a displacement, in the Y direction of Ay relative to x0 by an angle of ΘΠΪ. In the basket mode shown in FIG. 28C, the electroactive polymer 934 is shaped like a basket and is capable of expanding and collapsing under the influence of a high-voltage potential between the HY+ and GND wires.
[0133] FIGS, 29 A and 29B illustrate some potential issues arising out of the piston mode movement depicted in FIG. 28A, In the piston mode, the electroactive polymer actuator 930 stack or roll may buckle instead of elongating in the longitudinal direction defined by the electroactive polymer actuator 930.
[0134] FIGS. 30 and 31 illustrate the bender mode previously discussed in connection with FIG. 28 B. In FIG. 30, the bending angle Θ is determined and in FIG. 31, the Ay displacement is determined. As shown in FIG. 30, the straight beam 932 is represented by the expression:
[0135] S2 - (π+ί)θ
[0136] and the bent beam 934 is represented by the expression: [0137] Si = πθ = έ
[0138] The angle Θ is small -3.2° and is calculated according to the following:
[0139] In FIG. 31 it is shown that for a small angle 0m~0, Ay=0.57mm and is calculated according to the followinj
%x Sl i
Figure imgf000031_0001
y = 0.00057 m = 0.57 mm
[0141] FIG. 32A is an exploded view of a unimorph electroactive polymer actuator 940 including relative dimensions thereof in accordance with the present invention. FIG. 32B is an assembled view of the unimorph electroactive polymer actuator 940 shown in FIG. 32A. With reference now to both FIGS. 32A and 32B, the unimorph electroactive polymer actuator 940 comprises an electroactive polymer roll 942, an electrically insulated sheet 944, and an electrical conductor 946. Although a set of suitable dimensions for implementing a unimorph electroactive polymer actuator 940 is disclosed in connection with the present invention, such dimensions should not be construed in a limiting manner, Rather, such dimensions may be modified for any suitable applications without departing from the overall scope of the present invention,
[0142] FIG. 33 is photograph showing several unimorph electroactive polymer actuators 940.
[0143] FIG. 34 is a graphical depiction 942 of measured movement of roll bender
electroactive polymer actuators. Theory: Δχ::::0.57 mm; Observed: Δχ=0.25-0.35 mm;
[block 0.025 .
[0144] FIG. 35 A illustrates spring rate on tension roll from loaded hoops 945 in accordance with the present invention. FIG. 35B is a graphical depiction 947 of force as a function of stretch ratio. From pure geometry, about a 30% increase in force can be achieved using a linear spring on the hoop. Bui this would require a great fattening of the electroactive polymer actuator. 10 degrees is about acceptable. But this only gives strain of 1 ,5%. Many smaller hoops at about 40 degrees could be acceptable. -20 degrees gives 6% strain; 30 degrees gives 1 5% strain; 40 degrees gives 30% strain. Nonlinear (strain softening) hoop spring could increase the steepness of the negative rate.
[0145] The force F is calculated as follows:
= -ky
Figure imgf000032_0001
Fn - F0 COS 0
Fu - Fy cot Θ
|iv, J - kd sin Θ cot O— kd cos Θ
x— d eos0
[0146] An average human ear canal is about 26 mm in length and 7 mm in diameter. The outer part of the canal consists of a cartilaginous soft body and a 0.5 - 1 .0 mm thick skin with glands and hair follicles. The glands produce ear wax, which has an important role in keeping the ear canal clean and protecting it from bacteria, fungi and insects. The outer soft part of the canal forms one third to one half of total canal length. The remaining inner part of the canal rests on the opening of the bony skul! and the skin in this part of the canal is tightly applied to the bone. The skin here is approximately 0.2 mm thick and it may be easily injured or ruptured. [0147] FIG. 36 is a diagram of the human ear 1000. Applied sound pressure 1002 at the ear eana! entrance 1 04, radiated sound pressure at the ear canal entrance 1004, applied force or displacement at the actuator attachment points 1008, and displacement of the footplate center in the direction of the longitudinal stapes axis 1010 are shown.
[0148] The foregoing examples of the present invention are offered for the purpose of illustration and not limitation. It will be apparent to those skilled in the art that the embodiments described herein may be modified or revised in various ways without departing from the spirit and scope of the invention. The scope of the invention is to be measured by the appended claims.
[0149] It is to be appreciated that the embodiments described herein illustrate example implementations, and that the functional elements, logical blocks, program modules, and circuits elements may be implemented in various other ways which are consistent with the described embodiments. Furthermore, the operations perfonned by such functional elements, logical blocks, program modules, and circuits elements may be combined and/or separated for a given implementation and may be performed by a greater number or fewer number of components or program modules. As will be apparent to those of skill in the art upon reading the present disclosure, each of the individual embodiments described and illustrated herein has discrete components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope of the present disclosure. Any recited method can be carried out in the order of events recited or in any other order which is logically possible.
[0150] It. will be appreciated that those ski lled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the present disclosure and are included within the scope thereof. Furthermore, all examples and conditional language recited herein are principally intended to aid the reader in understanding the principles described in the present disclosure and the concepts contributed to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, embodiments, and embodiments as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents and equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure. The scope of the present disclosure, therefore, is not intended to be limited to the exemplary embodiments and embodiments shown and described herein. Rather, the scope of present disclosure is embodied by the appended claims.
[0151] Groupings of alternative elements or embodiments disclosed herein are not to be construed as limitations. Each group member may be referred to and claimed individually or in any combination with other members of the group or other elements found herein, it is anticipated that one or more members of a group may be included in, or deleted from, a group for reasons of convenience and/or patentability.
[Θ152] While certain features of the embodiments have been illustrated as described above, many modifications, substitutions, changes and equivalents will now occur to those skilled in the art. It is therefore to be understood that the appended claims are intended to cover ail such modifications and changes as fall within the scope of the disclosed embodiments and appended claims.
[0153] Various aspects of the subject matter described herein are set out in the following numbered clauses:
[0154] 1. An eiectroactive polymer device comprising: first and second eiectroactive polymer actuators which are spatially separated, each of the eiectroactive polymer actuators comprising an eiectroactive polyraer film, at least one pair of opposing compliant electrodes, and at least one mechanical output region, wherein the mechanical output region is configured to move in response to an activation signal being applied to the eiectroactive polymer film; wherein the first eiectroactive polymer actuator is configured to receive a first high voltage electrical signal and the second eiectroactive polymer actuator is configured to receive a second high voltage electrical signal, wherein the first and second high voltage electrical signals are independently tunable in both frequency and amplitude.
[0155] 2. The eiectroactive polymer device according to Clause 1, wherein the first high v ltage electrical signal has a first frequency track and the second high v ltage electrical signal has a second frequency track, wherein the first frequency track is not the same as the second frequency track,
[0156] 3. The eiectroactive polymer device according to clause 2, wherein the frequencies of the first and second frequency tracks are approximately in the range of ~-lHz and -~150Hz, [0157] 4. The electroacti ve polymer device according to any of clauses 1 to 3 wherein the electroactive polymer device is an audio device further comprising at least one acoustic speaker which is configured to receive a first low voltage electrical signal that is tunable in both frequency and amplitude independently from the electroactive polymer actuators.
[0158] 5, The electroactive polymer device according to clause 4 further comprising at least a second acoustic speaker which is configured to receive a second low voltage electrical signal that is tunable in both frequency and amplitude independently from the electroactive polymer actuators.
[0159] 6, The electroactive polymer device according to clause 5, wherein amplitude and frequency of each of the first and second low voltage electrical signals is independently tunable for each of the first and second acoustic speakers.
[0160] 7. The electroactive polymer device according to one of clauses 1 to 6, wherein the device comprises one of an over-the-ear headphone, an inside-ihe-ear headphone, an in-the- ear audio device, a personal sound amplification device, a stress relief aid, a relaxation aid, a stimulation aid, and a hearing aid.
[0161] 8. The electroactive polymer device according to any of clauses 1 to 7 wherein the first and second electroactive polymer actuators are situated to provide motion on separate locations on a user's head and are driven to provide a binaural beat that is approximately the difference between the frequencies of the first and second electroactive polymer actuators.
[0162] 9. The electroactive polymer device according to one of clauses 1 to 8, wherein the device comprises an in-the-ear device, further comprising: a first hub; a first wall; and wherein the first electroactive polymer actuator located between the hub and the wall.
[0163] 10. The in-the-ear device according to clause 9, wherein the first electroactive polymer actuator is potted in a potting compound and is mounted to the hub and defines at least one cavity between an interior surface of the wall and an exterior surface of the electroactive polymer actuator or wherein the first electroactive polymer actuator is potted in a potting compound and mounted to the wall and defines at least one cavity between an interior surface of the electroactive polymer actuator and an exterior surface of the hub, or wherein the first electroactive polymer actuator is potted in a potting compound and is mounted to the wail and the hub to fill the space defined between an interior surface of the wail and an exterior surface of the hub. [0164] 1 1. The in-the-ear device according to clause 9, further comprising: a second hub; a second wall; and wherein the second electroactive polymer actuator located between the hub and the wall.
[0165| 12, The electroactive polymer device according to one of clauses 1 to 11, wherein the device comprises an in-the-ear audio device, further comprising: a first rigid case back; a first rigid case front; a first flexible rubber ear bud; wherein the first electroactive polymer actuator is located within the flexible ear bud.
[0166] 13. The in-the-ear audio device according to clause 12, further including a rigid sound tube formed as an integral feature of the flexible rubber ear bud, wherein the rigid sound tube is configured to attach to the rigid case front.
[0167] 14. The in-the-ear audio device according to clause 12, further comprising: a second rigid case back; a second rigid case front; a second flexible rubber ear bud; wherein the second electroactive polymer actuator located within the flexible ear bud.
[01681 15. A method of driving the device according to any of clauses 1 to 14 wherein the first and second electroactive polymer actuators are driven to provide a conductive audio response that couples to brain waves to induce one of mental relaxation or mental stimulation.

Claims

WHAT IS CLAIMED IS:
1. An electroactive polymer device comprising:
first and second electroactive polymer actuators which are spatially separated, each of the electroactive polymer actuators comprising an electroactive polymer film, at least one pair of opposing compliant electrodes, and at least one mechanical output region, wherein the mechanical output region is configured to move in response to an activation signal being applied to the electroactive polymer film;
wherein the first electroactive polymer actuator is configured to receive a first high voltage electrical signal and the second electroactive polymer actuator is configured to receive a second high voltage electrical signal, wherein the first and second high voltage electrical signals are independently tunable in both frequency and amplitude.
2. The electroactive polymer device according to Claim 1, wherein the first high voltage electrical signal has a first frequency track and the second high voltage electrical signal has a second frequency track, wherein the first frequency track is not the same as the second frequency track,
3. The electroactive polymer device according to Claim 2, wherein the frequencies of the first and second frequency tracks are approximately in the range of ~lHz and -150Hz.
4. The electroactive polymer device according to any of Claims 1 to 3 wherein the electroactive polymer device is an audio device further comprising at least one acoustic speaker which is configured to receive a first low voltage electrical signal that is tunable in both f equency and amplitude independently from the electroactive polymer actuators.
5. The electroactive polymer device according to Claim 4 further comprising at least a second acoustic speaker which is configured to receive a second low v ltage electrical signal that is tunable in both frequency and amplitude independently from the electroactive polymer actuators.
6. The electroactive polymer device according to Claim 5, wherein amplitude and frequency of each of the first and second low voltage electrical signals is independently tunable for each of the first and second acoustic speakers.
7. The electroactive polymer device according to one of Claims 1 to 6, wherein the device comprises one of an over-the-ear headphone, an inside-the-ear headphone, an in-the- ear audio device, a personal sound amplification device, a stress relief aid, a relaxation aid, a stimulation aid, and a hearing aid.
8. The electroactive polymer device according to any of Claims 1 to 7 wherein the first and second electroactive polymer actuators are situated to provide motion on separate locations on a user's head and are driven to provide a binaural beat that is approximately the difference between the frequencies of the first and second electroactive polymer actuators.
9. The electroactive polymer device according to one of Claims 1 to 8, wherein the device comprises an in-the-ear device, further comprising:
a first hub:
a first wall; and
wherein the first electroactive polymer actuator located between the hub and the wall.
10. The in-the-ear device according to Claim 9, wherein the first electroactive polymer actuator is potted in a potting compound and is mounted to the hub and defines at least one cavity between an interior surface of the wall and an exterior surface of the electroactive polymer actuator or wherein the first electroactive polymer actuator is potted in a potting compound and mounted to the wall and defines at least one cavity between an interior surface of the electroactive polymer actuator and an exterior surface of the hub, or wherein the first electroactive polymer actuator is potted in a potting compound and is mounted to the wall and the hub to fill the space defined between an interior surface of the wall and an exteri or surface of the hub.
1 1. The in-the-ear device according to Claim 9, further comprising:
a second hub;
a second wall; and
wherein the second electroactive polymer actuator located between the hub and the wall
12. The eleetroactive po mer d ice according to one of Claims" I to 1 1, wherein, th davfee comprises ai m~the*e¾f mdi& devie¾s further comprising:
a first rigid- ease bacfc;
a first rigid ease front;
a .first flexible rubber ear bud;
toein the first eleeteactive polymer actuator i located within the flexihie ear biat
13. The in. he-ear audio device according to Claim It, further isici ud a rigid soimd tube femred as an integral feature of the flexible rubber ear bu4.. wherein, the; rigid soun tithe is ¾ontlg«.red to attach to the rigid ease front.
14. T he: i«-fee-ear audio device according to Claini 12, further comprising;
a seeond ri gid ease hack;
a second rigid; case .front;
a second fed e rubber ear feud;
wherelri the second eleetroaeti polymer ac uator located within the flexible ear hud* i 5. A method of dri ving the devlee cco d ng to airy of Claims 1 t 1 nereiii tne first and second e!ectFoaetive polymer actuators are drivesi to provide a conduetiye audio espons that couples to brain waves to Indixse one: of mental reiaxahot or .mental stiniidatiorL
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109417121A (en) * 2016-06-29 2019-03-01 皇家飞利浦有限公司 EAP actuator and driving method
CN111615046A (en) * 2020-05-11 2020-09-01 腾讯音乐娱乐科技(深圳)有限公司 Audio signal processing method and device and computer readable storage medium

Citations (71)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6343129B1 (en) 1997-02-07 2002-01-29 Sri International Elastomeric dielectric polymer film sonic actuator
US6376971B1 (en) 1997-02-07 2002-04-23 Sri International Electroactive polymer electrodes
US6545384B1 (en) 1997-02-07 2003-04-08 Sri International Electroactive polymer devices
US6543110B1 (en) 1997-02-07 2003-04-08 Sri International Electroactive polymer fabrication
US6586859B2 (en) 2000-04-05 2003-07-01 Sri International Electroactive polymer animated devices
US6628040B2 (en) 2000-02-23 2003-09-30 Sri International Electroactive polymer thermal electric generators
US6664718B2 (en) 2000-02-09 2003-12-16 Sri International Monolithic electroactive polymers
US6707236B2 (en) 2002-01-29 2004-03-16 Sri International Non-contact electroactive polymer electrodes
US6768246B2 (en) 2000-02-23 2004-07-27 Sri International Biologically powered electroactive polymer generators
US6781284B1 (en) 1997-02-07 2004-08-24 Sri International Electroactive polymer transducers and actuators
US6806621B2 (en) 2001-03-02 2004-10-19 Sri International Electroactive polymer rotary motors
US6809462B2 (en) 2000-04-05 2004-10-26 Sri International Electroactive polymer sensors
US6812624B1 (en) 1999-07-20 2004-11-02 Sri International Electroactive polymers
US6876135B2 (en) 2001-10-05 2005-04-05 Sri International Master/slave electroactive polymer systems
US6882086B2 (en) 2001-05-22 2005-04-19 Sri International Variable stiffness electroactive polymer systems
US6891317B2 (en) 2001-05-22 2005-05-10 Sri International Rolled electroactive polymers
US6911764B2 (en) 2000-02-09 2005-06-28 Sri International Energy efficient electroactive polymers and electroactive polymer devices
US6940221B2 (en) 2002-10-10 2005-09-06 Hitachi Displays, Ltd. Display device
US7034432B1 (en) 1997-02-07 2006-04-25 Sri International Electroactive polymer generators
US7052594B2 (en) 2002-01-31 2006-05-30 Sri International Devices and methods for controlling fluid flow using elastic sheet deflection
US7064472B2 (en) 1999-07-20 2006-06-20 Sri International Electroactive polymer devices for moving fluid
US7166953B2 (en) 2001-03-02 2007-01-23 Jon Heim Electroactive polymer rotary clutch motors
US7233097B2 (en) 2001-05-22 2007-06-19 Sri International Rolled electroactive polymers
US20070200457A1 (en) 2006-02-24 2007-08-30 Heim Jonathan R High-speed acrylic electroactive polymer transducers
US20070230222A1 (en) 2006-03-31 2007-10-04 Drabing Richard B Power circuitry for high-frequency applications
US7320457B2 (en) 1997-02-07 2008-01-22 Sri International Electroactive polymer devices for controlling fluid flow
US7394282B2 (en) 2006-06-28 2008-07-01 Intel Corporation Dynamic transmission line termination
US7436099B2 (en) 2003-08-29 2008-10-14 Sri International Electroactive polymer pre-strain
US7492076B2 (en) 2006-12-29 2009-02-17 Artificial Muscle, Inc. Electroactive polymer transducers biased for increased output
US7521847B2 (en) 2005-03-21 2009-04-21 Artificial Muscle, Inc. High-performance electroactive polymer transducers
US7521840B2 (en) 2005-03-21 2009-04-21 Artificial Muscle, Inc. High-performance electroactive polymer transducers
US7567681B2 (en) 2003-09-03 2009-07-28 Sri International Surface deformation electroactive polymer transducers
US7595580B2 (en) 2005-03-21 2009-09-29 Artificial Muscle, Inc. Electroactive polymer actuated devices
US7608989B2 (en) 1999-07-20 2009-10-27 Sri International Compliant electroactive polymer transducers for sonic applications
US7626319B2 (en) 2005-03-21 2009-12-01 Artificial Muscle, Inc. Three-dimensional electroactive polymer actuated devices
US7750532B2 (en) 2005-03-21 2010-07-06 Artificial Muscle, Inc. Electroactive polymer actuated motors
US7911761B2 (en) 2006-12-14 2011-03-22 Bayer Materialscience Ag Fault-tolerant materials and methods of fabricating the same
US7915789B2 (en) 2005-03-21 2011-03-29 Bayer Materialscience Ag Electroactive polymer actuated lighting
US7952261B2 (en) 2007-06-29 2011-05-31 Bayer Materialscience Ag Electroactive polymer transducers for sensory feedback applications
US20110128239A1 (en) 2007-11-21 2011-06-02 Bayer Materialscience Ag Electroactive polymer transducers for tactile feedback devices
WO2011097020A2 (en) 2010-02-03 2011-08-11 Bayer Materialscience Ag An electroactive polymer actuator haptic grip assembly
WO2011102898A2 (en) 2010-02-16 2011-08-25 Bayer Materialscience Ag Haptic apparatus and techniques for quantifying capability thereof
US20120126667A1 (en) 2009-07-02 2012-05-24 Bayer Materialscience Ag Method for obtaining electrical energy from the kinetic energy of waves
US20120126959A1 (en) 2008-11-04 2012-05-24 Bayer Materialscience Ag Electroactive polymer transducers for tactile feedback devices
US8222799B2 (en) 2008-11-05 2012-07-17 Bayer Materialscience Ag Surface deformation electroactive polymer transducers
WO2012099850A2 (en) 2011-01-18 2012-07-26 Bayer Materialscience Ag Flexure apparatus, system, and method
WO2012099854A1 (en) 2011-01-18 2012-07-26 Bayer Materialscience Ag Frameless actuator apparatus, system, and method
US20120206248A1 (en) 2009-10-19 2012-08-16 Biggs Silmon James Flexure assemblies and fixtures for haptic feedback
US8248750B2 (en) 2007-12-13 2012-08-21 Bayer Materialscience Ag Electroactive polymer transducers
WO2012118916A2 (en) 2011-03-01 2012-09-07 Bayer Materialscience Ag Automated manufacturing processes for producing deformable polymer devices and films
WO2012122438A2 (en) 2011-03-09 2012-09-13 Bayer Materialscience Ag Electroactive polymer actuator feedback apparatus system, and method
WO2012120009A1 (en) 2011-03-07 2012-09-13 Bayer Materialscience Ag Layer composite comprising electroactive layers
WO2012122440A2 (en) 2011-03-09 2012-09-13 Bayer Materialscience Ag Electroactive polymer energy converter
WO2012129357A2 (en) 2011-03-22 2012-09-27 Bayer Materialscience Ag Electroactive polymer actuator lenticular system
WO2012136503A1 (en) 2011-04-07 2012-10-11 Bayer Materialscience Ag Use of thermoplastic polyurethanes for converting mechanical energy to electrical energy
WO2012148644A2 (en) 2011-04-07 2012-11-01 Bayer Materialscience Ag Conductive polymer fuse
WO2012156423A1 (en) 2011-05-16 2012-11-22 Bayer Intellectual Property Gmbh Method for operating a component
WO2012173669A2 (en) 2011-06-16 2012-12-20 Bayer Materialscience Ag Audio devices having electroactive polymer actuators
WO2012175533A1 (en) 2011-06-20 2012-12-27 Bayer Intellectual Property Gmbh Conductor assembly
WO2013037508A1 (en) 2011-04-07 2013-03-21 Bayer Materialscience Ag Use of thermoplastic polyurethanes for generating electrical energy from wave energy
WO2013049485A1 (en) 2011-09-29 2013-04-04 Bayer Material Science Ag Dielectric elastomers having a two-dimensionally structured surface, and electromechanical converter comprising such dielectric elastomers
WO2013059560A1 (en) 2011-10-21 2013-04-25 Bayer Materialscience Ag Dielectric elastomer membrane feedback apparatus, system and method
WO2013059562A1 (en) 2011-10-21 2013-04-25 Bayer Materialscience Ag Electroactive polymer energy converter
WO2013103470A1 (en) 2011-12-09 2013-07-11 Bayer Intellectual Property Gmbh Techniques for fabricating an actuator element
US20130194082A1 (en) 2010-03-17 2013-08-01 Bayer Intellectual Property Gmbh Static analysis of audio signals for generation of discernable feedback
WO2013142552A1 (en) 2012-03-21 2013-09-26 Bayer Materialscience Ag Roll-to-roll manufacturing processes for producing self-healing electroactive polymer devices
WO2013148641A1 (en) 2012-03-27 2013-10-03 Bayer Material Science Ag Rotational inertial drive system and bearing systems for electroactive polymer devices
WO2013155377A1 (en) 2012-04-12 2013-10-17 Bayer Materialscience Ag Eap transducers with improved performance
WO2013192143A1 (en) 2012-06-18 2013-12-27 Bayer Intellectual Property Gmbh Stretch frame for stretching process
WO2014006005A1 (en) 2012-07-03 2014-01-09 Bayer Materialscience Ag Method for producing a multilayer dielectric polyurethane film system
WO2014028825A1 (en) 2012-08-16 2014-02-20 Bayer Intellectual Property Gmbh Rolled and compliant dielectric elastomer actuators

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7981064B2 (en) * 2005-02-18 2011-07-19 So Sound Solutions, Llc System and method for integrating transducers into body support structures
US8213670B2 (en) * 2007-06-07 2012-07-03 Acousticsheep, Llc Sleep aid system and method
US8317734B1 (en) * 2009-06-19 2012-11-27 Integrated Listening Systems, LLC Bone conduction pad

Patent Citations (86)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6781284B1 (en) 1997-02-07 2004-08-24 Sri International Electroactive polymer transducers and actuators
US7320457B2 (en) 1997-02-07 2008-01-22 Sri International Electroactive polymer devices for controlling fluid flow
US7062055B2 (en) 1997-02-07 2006-06-13 Sri International Elastomeric dielectric polymer film sonic actuator
US7034432B1 (en) 1997-02-07 2006-04-25 Sri International Electroactive polymer generators
US6543110B1 (en) 1997-02-07 2003-04-08 Sri International Electroactive polymer fabrication
US6343129B1 (en) 1997-02-07 2002-01-29 Sri International Elastomeric dielectric polymer film sonic actuator
US6376971B1 (en) 1997-02-07 2002-04-23 Sri International Electroactive polymer electrodes
US6583533B2 (en) 1997-02-07 2003-06-24 Sri International Electroactive polymer electrodes
US6545384B1 (en) 1997-02-07 2003-04-08 Sri International Electroactive polymer devices
US7368862B2 (en) 1999-07-20 2008-05-06 Sri International Electroactive polymer generators
US7362032B2 (en) 1999-07-20 2008-04-22 Sri International Electroactive polymer devices for moving fluid
US7608989B2 (en) 1999-07-20 2009-10-27 Sri International Compliant electroactive polymer transducers for sonic applications
US6812624B1 (en) 1999-07-20 2004-11-02 Sri International Electroactive polymers
US7224106B2 (en) 1999-07-20 2007-05-29 Sri International Electroactive polymers
US7211937B2 (en) 1999-07-20 2007-05-01 Sri International Electroactive polymer animated devices
US7199501B2 (en) 1999-07-20 2007-04-03 Sri International Electroactive polymers
US7064472B2 (en) 1999-07-20 2006-06-20 Sri International Electroactive polymer devices for moving fluid
US7259503B2 (en) 1999-07-20 2007-08-21 Sri International Electroactive polymers
US7049732B2 (en) 1999-07-20 2006-05-23 Sri International Electroactive polymers
US6664718B2 (en) 2000-02-09 2003-12-16 Sri International Monolithic electroactive polymers
US6911764B2 (en) 2000-02-09 2005-06-28 Sri International Energy efficient electroactive polymers and electroactive polymer devices
US6768246B2 (en) 2000-02-23 2004-07-27 Sri International Biologically powered electroactive polymer generators
US6628040B2 (en) 2000-02-23 2003-09-30 Sri International Electroactive polymer thermal electric generators
US6809462B2 (en) 2000-04-05 2004-10-26 Sri International Electroactive polymer sensors
US6586859B2 (en) 2000-04-05 2003-07-01 Sri International Electroactive polymer animated devices
US7166953B2 (en) 2001-03-02 2007-01-23 Jon Heim Electroactive polymer rotary clutch motors
US7378783B2 (en) 2001-03-02 2008-05-27 Sri International Electroactive polymer torsional device
US6806621B2 (en) 2001-03-02 2004-10-19 Sri International Electroactive polymer rotary motors
US6891317B2 (en) 2001-05-22 2005-05-10 Sri International Rolled electroactive polymers
US7233097B2 (en) 2001-05-22 2007-06-19 Sri International Rolled electroactive polymers
US7761981B2 (en) 2001-05-22 2010-07-27 Sri International Methods for fabricating an electroactive polymer device
US6882086B2 (en) 2001-05-22 2005-04-19 Sri International Variable stiffness electroactive polymer systems
US6876135B2 (en) 2001-10-05 2005-04-05 Sri International Master/slave electroactive polymer systems
US6707236B2 (en) 2002-01-29 2004-03-16 Sri International Non-contact electroactive polymer electrodes
US7052594B2 (en) 2002-01-31 2006-05-30 Sri International Devices and methods for controlling fluid flow using elastic sheet deflection
US6940221B2 (en) 2002-10-10 2005-09-06 Hitachi Displays, Ltd. Display device
US7436099B2 (en) 2003-08-29 2008-10-14 Sri International Electroactive polymer pre-strain
US7567681B2 (en) 2003-09-03 2009-07-28 Sri International Surface deformation electroactive polymer transducers
US7915789B2 (en) 2005-03-21 2011-03-29 Bayer Materialscience Ag Electroactive polymer actuated lighting
US7521847B2 (en) 2005-03-21 2009-04-21 Artificial Muscle, Inc. High-performance electroactive polymer transducers
US7521840B2 (en) 2005-03-21 2009-04-21 Artificial Muscle, Inc. High-performance electroactive polymer transducers
US8183739B2 (en) 2005-03-21 2012-05-22 Bayer Materialscience Ag Electroactive polymer actuated devices
US7595580B2 (en) 2005-03-21 2009-09-29 Artificial Muscle, Inc. Electroactive polymer actuated devices
US7626319B2 (en) 2005-03-21 2009-12-01 Artificial Muscle, Inc. Three-dimensional electroactive polymer actuated devices
US7750532B2 (en) 2005-03-21 2010-07-06 Artificial Muscle, Inc. Electroactive polymer actuated motors
US20070200457A1 (en) 2006-02-24 2007-08-30 Heim Jonathan R High-speed acrylic electroactive polymer transducers
US20070230222A1 (en) 2006-03-31 2007-10-04 Drabing Richard B Power circuitry for high-frequency applications
US7394282B2 (en) 2006-06-28 2008-07-01 Intel Corporation Dynamic transmission line termination
US7911761B2 (en) 2006-12-14 2011-03-22 Bayer Materialscience Ag Fault-tolerant materials and methods of fabricating the same
US7492076B2 (en) 2006-12-29 2009-02-17 Artificial Muscle, Inc. Electroactive polymer transducers biased for increased output
US7952261B2 (en) 2007-06-29 2011-05-31 Bayer Materialscience Ag Electroactive polymer transducers for sensory feedback applications
US20110128239A1 (en) 2007-11-21 2011-06-02 Bayer Materialscience Ag Electroactive polymer transducers for tactile feedback devices
US8248750B2 (en) 2007-12-13 2012-08-21 Bayer Materialscience Ag Electroactive polymer transducers
US20120126959A1 (en) 2008-11-04 2012-05-24 Bayer Materialscience Ag Electroactive polymer transducers for tactile feedback devices
US8222799B2 (en) 2008-11-05 2012-07-17 Bayer Materialscience Ag Surface deformation electroactive polymer transducers
US20120126667A1 (en) 2009-07-02 2012-05-24 Bayer Materialscience Ag Method for obtaining electrical energy from the kinetic energy of waves
US20120206248A1 (en) 2009-10-19 2012-08-16 Biggs Silmon James Flexure assemblies and fixtures for haptic feedback
WO2011097020A2 (en) 2010-02-03 2011-08-11 Bayer Materialscience Ag An electroactive polymer actuator haptic grip assembly
US20130002587A1 (en) 2010-02-16 2013-01-03 Biggs Silmon James Haptic apparatus and techniques for quantifying capability thereof
WO2011102898A2 (en) 2010-02-16 2011-08-25 Bayer Materialscience Ag Haptic apparatus and techniques for quantifying capability thereof
US20130194082A1 (en) 2010-03-17 2013-08-01 Bayer Intellectual Property Gmbh Static analysis of audio signals for generation of discernable feedback
WO2012099854A1 (en) 2011-01-18 2012-07-26 Bayer Materialscience Ag Frameless actuator apparatus, system, and method
WO2012099850A2 (en) 2011-01-18 2012-07-26 Bayer Materialscience Ag Flexure apparatus, system, and method
WO2012118916A2 (en) 2011-03-01 2012-09-07 Bayer Materialscience Ag Automated manufacturing processes for producing deformable polymer devices and films
WO2012120009A1 (en) 2011-03-07 2012-09-13 Bayer Materialscience Ag Layer composite comprising electroactive layers
WO2012122438A2 (en) 2011-03-09 2012-09-13 Bayer Materialscience Ag Electroactive polymer actuator feedback apparatus system, and method
WO2012122440A2 (en) 2011-03-09 2012-09-13 Bayer Materialscience Ag Electroactive polymer energy converter
WO2012129357A2 (en) 2011-03-22 2012-09-27 Bayer Materialscience Ag Electroactive polymer actuator lenticular system
WO2012148644A2 (en) 2011-04-07 2012-11-01 Bayer Materialscience Ag Conductive polymer fuse
WO2013037508A1 (en) 2011-04-07 2013-03-21 Bayer Materialscience Ag Use of thermoplastic polyurethanes for generating electrical energy from wave energy
WO2012136503A1 (en) 2011-04-07 2012-10-11 Bayer Materialscience Ag Use of thermoplastic polyurethanes for converting mechanical energy to electrical energy
WO2012156423A1 (en) 2011-05-16 2012-11-22 Bayer Intellectual Property Gmbh Method for operating a component
WO2012173669A2 (en) 2011-06-16 2012-12-20 Bayer Materialscience Ag Audio devices having electroactive polymer actuators
WO2012175533A1 (en) 2011-06-20 2012-12-27 Bayer Intellectual Property Gmbh Conductor assembly
WO2013049485A1 (en) 2011-09-29 2013-04-04 Bayer Material Science Ag Dielectric elastomers having a two-dimensionally structured surface, and electromechanical converter comprising such dielectric elastomers
WO2013059560A1 (en) 2011-10-21 2013-04-25 Bayer Materialscience Ag Dielectric elastomer membrane feedback apparatus, system and method
WO2013059562A1 (en) 2011-10-21 2013-04-25 Bayer Materialscience Ag Electroactive polymer energy converter
WO2013103470A1 (en) 2011-12-09 2013-07-11 Bayer Intellectual Property Gmbh Techniques for fabricating an actuator element
WO2013142552A1 (en) 2012-03-21 2013-09-26 Bayer Materialscience Ag Roll-to-roll manufacturing processes for producing self-healing electroactive polymer devices
WO2013148641A1 (en) 2012-03-27 2013-10-03 Bayer Material Science Ag Rotational inertial drive system and bearing systems for electroactive polymer devices
WO2013155377A1 (en) 2012-04-12 2013-10-17 Bayer Materialscience Ag Eap transducers with improved performance
WO2013192143A1 (en) 2012-06-18 2013-12-27 Bayer Intellectual Property Gmbh Stretch frame for stretching process
WO2014006005A1 (en) 2012-07-03 2014-01-09 Bayer Materialscience Ag Method for producing a multilayer dielectric polyurethane film system
WO2014028825A1 (en) 2012-08-16 2014-02-20 Bayer Intellectual Property Gmbh Rolled and compliant dielectric elastomer actuators
WO2014028822A1 (en) 2012-08-16 2014-02-20 Bayer Intellectual Property Gmbh Electrical interconnect terminals for rolled dielectric elastomer transducers
WO2014028819A1 (en) 2012-08-16 2014-02-20 Bayer Intellectual Property Gmbh Machine and methods for making rolled dielectric elastomer transducers

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109417121A (en) * 2016-06-29 2019-03-01 皇家飞利浦有限公司 EAP actuator and driving method
CN111615046A (en) * 2020-05-11 2020-09-01 腾讯音乐娱乐科技(深圳)有限公司 Audio signal processing method and device and computer readable storage medium

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