Because no physical contact with a control device is required, user self image may also improve. With no exposed moving parts, the system is quite durable. The PHC-2 emulates a standard proportional joystick control unit and can plug directly into the wheelchair motor drive controller. Set up involves little more than setting appropriate controller program values. The user selects the desired drive code by activating a light touch switch concealed in the headrest.
Selection is made by tapping gently with the back of the head.
For forward drive, three taps activate the switch. The user then tilts his head forward from the vertical position to produce forward motion. The speed attained is proportional to the degree of lateral head tilt. Turning can be accomplished with or without forward motion. Motion is reduced to zero as the head is returned to the vertical position.