WO2008029151A1

WO2008029151A1 - Environmental control system

Info

Publication number: WO2008029151A1
Application number: PCT/GB2007/003373
Authority: WO
Inventors: Ian Bancroft Anderson
Original assignee: Pure Ability Limited
Priority date: 2006-09-08
Filing date: 2007-09-07
Publication date: 2008-03-13
Also published as: GB0617720D0

Abstract

An environmental control system of inclusion with a wheelchair comprises a pressure-sensitive control means for disposition in or adjacent the wheelchair back support for manual actuation by the wheelchair user, in use. The control means comprises at least one pressure-sensitive zone comprising means for sensing pressure applied in a discrete location and/or means for sensing pressure applied as a progressive movement in a given direction across the surface of the control means.

Description

Environmental Control System

This invention relates to an environmental control system for incorporation in a wheelchair, especially for use by disabled people who have restricted hand function.

Disabled people who are essentially confined to wheelchairs have a need to exercise control over external or remote devices and systems, for example televisions, telephones, stereo equipment and the like. Whereas means for exercising remote control over such systems and devices are available, they generally require a degree of manual dexterity which is often unavailable to disabled people.

There is also a need for disabled people to be made aware of occasions when devices or systems require operational control to be exercised or a response made, for example to answer an incoming telephone call where the ring tone is set to "silent", or to receive reminders regarding certain events, such as that the person should relieve pressure, for example by leaning forward or lifting up off the cushion for a few seconds, after a predetermined period of time to avoid pressure sores developing.

Various control systems for wheelchairs are known, typically mounted on an armrest or on a tray or other support spaced above the user's thighs. Such systems are generally intended for motorised wheelchairs which are inevitably large, heavy and cumbersome, needing not only to include the motor, power pack and drive train components but also to be manufactured from heavy-duty materials capable of supporting such components. Manual wheelchairs do not require such components and, to the extent that they may require control systems for external devices, the balance and general ease of use, for example when the user wishes to transfer to or from the chair, is compromised by their being mounted in such locations.

It is an object of the present invention to provide an environmental control system especially suitable for a manual wheelchair. In one aspect, the present invention provides a wheelchair including an environmental control system, in which the system comprises pressure-sensitive control means incorporated in or disposed adjacent the wheelchair back support for manual actuation by the wheelchair user in use.

In another aspect, the invention provides an environmental control system for inclusion with a wheelchair, in which the system comprises a pressure-sensitive control means for disposition in or adjacent the wheelchair back support for manual actuation by the wheelchair user, in use.

In the present invention, it is preferred that the wheelchair is of the manual type, that is, it can be propelled either by the user turning the main wheels by hand or by an assistant pushing from behind.

The control means preferably comprises at least one pressure-sensitive interface zone which itself may comprise means for sensing pressure applied in a discrete location and/or means for sensing pressure applied as a progressive movement in a given direction across the surface of the control means. Preferably, the control means are incorporated in the rearwardly-facing part of the wheelchair back support, just beneath the surface and in operative contact with the surface material. Preferably, the back support incorporates two pressure-sensitive control means, disposed respectively on either side of the back support, generally in that region which, with the chair being occupied by a user, is adjacent the pelvic region of the user's body. In this position, the control means can readily be reached by the user extending the hands behind and to the rear and inwardly of the side edges of the back support and activated by the application of pressure to the control means to cause electrical contact to be made, preferably with a central control unit as described hereinafter.

In order to avoid unintentional pressure being applied to the control means, the control means are preferably disposed within a shield or guard means, for example a shallow tray the edges of which prevent any forces exerted on the material of the backrest by the user leaning thereagainst being transmitted to the pressure-sensitive control means. The control means may comprise a touch-sensitive fabric material which is able to detect where and preferably also how hard it is being pressed, by evaluating X, Y and Z axis co-ordinates across and through the fabric sensor using integral software. The output therefore can discriminate between contact at one discrete location and movement across the fabric surface and is further able to identify the precise position of the contact or the direction and extent of the movement. Such materials generally comprise a laminate of fabric layers having a total thickness less than lmm, By way of example, one suitable material is commercially available as "Elek Tex" (TM) sensor material having a thickness of 0.6mm.

In another aspect, the present invention provides a wheelchair having a back support, in which the rearwardly-facing surface of the back support comprises a touch-sensitive fabric material in operative connection with other elements of an environmental control system associated with the wheelchair.

The control means is preferably operatively connected to a central control unit such as a microprocessor having outputs connected to or being capable of connection to operational systems or devices, as required. The system also includes a battery or other power supply, for example a solar-powered cell, and preferably a clock or time counter for recording events or initiating events at a predetermined time or after lapse of a predetermined time period.

A wheelchair or system according to the present invention preferably also includes means to alert or notify the user of a relevant event which requires a response from the user. Such means may comprise one or more vibration-inducing means located preferably in the back support for notifying or alerting the user to events such as an incoming telephone call or a time-controlled alarm for some particular purpose. Where two or more vibration-inducing means are employed, they are preferably spaced apart within the back or other support of the wheelchair and are connected to the central control unit to provide programmed signals or signal patterns depending on and representative of the nature of the event being notified. For example, the vibration-inducing means may be programmed to be actuated either simultaneously, either continuously or intermittently, or sequentially, whereby when actuated sequentially the user perceives a vibration signal which moves progressively in one direction or the other. The vibration-inducing means may comprise an electric motor, a vibrating solenoid or the like provided that it is capable of being sensed by the user sitting in the wheelchair. Preferably, the vibration-inducing means are disposed in the upper part of the back support cushion, whereby any signal from sequential operation of the vibration-inducing means is perceived as a signal which moves laterally across the back of the user but a height at which the user is capable of perceiving the signal, having regard to the physical disability suffered by the user and any resulting zone of numbness where the user may be incapable of feeling or sensing vibrations. Preferably, the number of vibration-inducing means is five, this number being regarded as the optimum for providing a sensation of a moving vibration.

The system according to the invention preferably includes a pressure sensor placed inu or beneath the seat cushion of the wheelchair for activation when the wheelchair is occupied. Preferably, the pressure sensor is periodically interrogated by the control system to determine whether or not the wheelchair is occupied and, when it is determined that the wheelchair is occupied, the mode of the system will be changed from quiescent to active and the remaining elements of the system will also then be rendered active for use. A manual on/off power switch is therefore preferably also included in the system. When switched on, the control unit may include a "sleep" mode in which the controller interrogates or polls the pressure-sensitive power switch at a slower rate than in the "active" mode, in order to conserve power.

Optionally, the system according to the invention includes RF sensors to support a nurse call system directly from the backrest of the chair, or for other purposes sensitive to RF signals.

In use, the user may be able to activate controls to external systems or devices by performing tap and stroke gestures on a pressure-sensitive control means, the central control unit being capable of discriminating between them and sending appropriate output signals. For example, a tap gesture may be used to select a desired function and thereafter a stroke gesture performed on the control means to increase or decrease the function, as required. In one instance, a television channel may be changed by performing a tap gesture to select the television channel function and thereafter performing a stroke gesture to change the channel up or down, as required. Similarly, the volume may be controlled by performing a stroke gesture on the volume function previously selected by a tap gesture. Other devices which may be controlled in a similar way include MP3 or other audio devices; mobile telephones, via wireless interface such as a Bluetooth device; and other domestic apparatus such as ovens via a suitable transmitter operatively connected with a compatible receiver on the apparatus.

For the alerting mode or function, the system according to the invention may include a wireless, for example Bluetooth, receiver for receiving messages from devices equipped with Bluetooth transmitters, such as mobile telephones; and means to programme the control unit according to user-dictated requirements regarding, for example, reminder signals for a change of posture or for any other purpose. The control unit may be re-programmed or updated by the user at any time, for example in order to set a new configuration for a television by downloading new infrared codes. For this purpose, the user will connect the control unit to a computer via a standard connection such as a USB, Firewire or serial connector, and run software for example downloaded from a website supporting the control unit or obtained from distribution of a CD or DVD.

In a hypothetical situation given by way of example of use of a wheelchair according to the invention, it is assumed that the user transfers from the bed to the wheelchair. The microprocessor (as the central control unit), hitherto in "sleep" mode, detects the presence of the user by periodic polling of the pressure sensor located in the seat cushion and, upon sensing the presence of the user in the chair, the microprocessor begins periodically to poll the touch sensitive panels located on the rear of the chair. The mobile phone of the user is set to be silent and is kept in a bag or other receptacle located beneath the wheelchair Seat cushion. An incoming call initiates vibration of the phone, the incoming call information being relayed to the microprocessor. The microprocessor activates the vibrating motors located in the back support of the wheelchair in a specific pattern corresponding to a "call received" event, for example by being switched simultaneously on for a second (or other prearranged period of time), followed by being switched off for a further second or other prearranged period. The user is thus alerted to the fact that an incoming call is being made, without any ringing tone noise being emitted. In an alternative scenario, the user is listening to music on an audio device and uses the touch-sensitive controls located on the rear of the chair by tapping and/or stroking gestures, for example to play the previous music track, jump forwards to the next track, change the volume and so on.

Embodiments of the invention will now be described by way of example with reference to the accompanying Figure 1 drawing, which represents diagrammatically the location of components of a system according to the invention when disposed on or within the upholstery of a wheelchair.

With reference to the drawing, the wheelchair upholstery includes a back support including a lower forwardly-extending part 11 which in use is disposed under the seat cushion, a forwards-facing backrest cushion surface 12 which, in use, will be in contact with 'the user's back and a rearwards-facing backrest cushion surface 13. The fold line between the forwardly-extending part 11 and backrest cushion is shown as Fl and the fold line over the top of the backrest frame and which defines the border between the forwards- and rearwards-facing cushion surfaces is shown as F2. A pressure-sensitive panel 14 is incorporated in the part 11 to act as a switch to detect the presence of a person in the chair and vibrating motors 15-19 are disposed along the upper edge region of the forwards-facing backrest cushion surface 12. On the rear-facing surface 13, touch-sensitive panels 20, 21 are provided in the lumbar regions, each panel being capable through the microcontroller 22 of distinguishing between tap gestures and stroke gestures and providing an output accordingly. The rear of the backrest is also provided with a power button 23, battery 24 and a clock 25. A Bluetooth receiver and transmitter 26 and an RF transmitter 27 are also included. The touch-sensitive panels 20, 21 in the embodiment described are formed from "Elek Tex" touch-sensitive fabric to provide the interface to the microcontroller.

The output from the microcontroller 22 to the motors 15 to 19 is arranged either to actuate the motors simultaneously, continuously or intermittently, or sequentially either in the order 15-16-17-18-19 or in the order 19-18-17-16-15, according to the nature of the input command to the microcontroller either from an external device or an internal clocked programme.

Claims

1. An environmental control system for inclusion with a wheelchair, in which the system comprises a pressure-sensitive control means for disposition in or adjacent the wheelchair back support for manual actuation by the wheelchair user, in use.

2. A system according to claim 1, in which the control means comprises at least one pressure-sensitive zone comprising means for sensing pressure applied in a discrete location and/or means for sensing pressure applied as a progressive movement in a given direction across the surface of the control means.

3. A system according to claim 1 or claim 2 including two pressure-sensitive control means for disposition respectively on either side of the rearwardly-facing part of the wheelchair back support.

4. A system according to any preceding claim, in which the control means are disposed within a shield or guard means for prevention of forces being unintentionally operatively transmitted to the pressure-sensitive control means.

5. A system according to any preceding claim, in which the control means comprise a touch-sensitive fabric material.

6. A system according to any preceding claim, in which the control means is operatively connected to a central control unit having outputs connected to or being capable of connection to operational systems or devices, a power supply, and preferably a clock or time counter.

7. A system according to any preceding claim, further including means to alert or notify the user of an event requiring a response to be made by the user.

8. A system according to claim 7, in which the altering or notifying means comprises one or more vibration-inducing means for location in the wheelchair back or other support.

9. A system according to claim 8 including two or more vibration-inducing means, the vibration-inducing means being spaced apart within the back or other support of the wheelchair and connected to the central control unit to provide programmed signals or signal patterns depending on and representative of the nature of the event being notified.

10. A system according to claim 8 or claim 9, in which the vibration-inducing means comprises an electric motor or a vibrating solenoid.

11. A system according to any of claims 8 to 10, in which the vibration-inducing means are disposed in the upper part of the back support cushion of the wheelchair, whereby sequential operation of the vibration-inducing means is perceived as a signal which moves laterally across the back of the user.

12. A system according to any preceding claim, further including a pressure sensor placed in or beneath the seat cushion of the wheelchair for activation when the wheelchair is occupied, the pressure sensor being periodically interrogated by the control system to determine whether or not the wheelchair is occupied and changing the mode of the system from quiescent to active accordingly.

13. A system according to claim 12, including a manual on/off power switch, the control unit preferably including a "sleep" mode in which the controller interrogates or polls the pressure-sensitive power switch at a slower rate than in the "active" mode.

14. A system according to any preceding claim, further including RF sensors to support a nurse call system or for other purposes sensitive to RF signals.

15. A system according to any of claims 7 to 14, in which the alerting or notifying means includes a wireless receiver.

16. A system according to any of claims 7 to 15, including means to programme the control unit according to user-dictated requirements.

17. A system according to claim 16, including connection means to a computing device.

18. A wheelchair including an environmental control system according to any of claims 1 to 17.

19. A wheelchair according to claim 18, in which the wheelchair has a back support the rearwardly-facing surface of which comprises a touch-sensitive fabric material in operative connection with other elements of the environmental control system.

20. A method of operating external systems or devices by a user from a wheelchair according to claim 18 or claim 19, the method comprising the user performing tap and/or stroke gestures on the pressure-sensitive control means, the central control unit being capable of discriminating between such gestures and sending appropriate output signals to the external systems or devices.