An ultrasonic head position interface for wheelchair control.

To give quadriplegics independent mobility, a "smart" microprocessor-based electric wheelchair has been developed by the Palo Alto Veterans Administration Medical Center and Stanford University. Ultrasound distance-ranging technology is employed to track the user's head position in two-dimensional space. These data are then used to determine the chair's direction and speed. A working prototype vehicle using this type of motion control has been successfully demonstrated. Obstacle detection, wall-following, and cruise control modes are other implemented features of the current design.