A force feedback mechanism designed for use with a mouse, trackball, keyboard, or other interface device manipulated by a user. The mechanism consists of a non-planar surface 11 that is substantially balanced with respect to a rotational axis "A." An actuator 12 controlled by a computer or microprocessor...http://www.google.de/patents/US6587091?utm_source=gb-gplus-sharePatent US6587091 - Stabilized tactile output mechanism for computer interface devices
