A force feedback joystick unit connected to the serial port of a personal computer applies a variety of force effects to the joystick handle in response to commands from the executing personal computer program. Forces are applied to the joystick, which is mounted on a gimbal support for movement...http://www.google.com.au/patents/US5742278?utm_source=gb-gplus-sharePatent US5742278 - Force feedback joystick with digital signal processor controlled by host processor 
