Vision aid for power wheelchair users

The sitting posture of power wheelchair (WC) users greatly limits their overall visibility. Without the ability to stand or lean forward, WC users are prevented from peering over most obstacles and into deep containers. A vision aid to raise or extend forward the line of sight of power WC users would be useful in many daily living, educational, and occupational activities. The design of the WC camera was based on the human factor requirements of a quadriplegic WC user and the results of a detailed House of Quality. The development of a pulley and belt-driven linkage system with a digital camera satisfied the top-ranked client and engineering requirements. Comprehensive engineering analyses were also performed to study the strength, safety, and failure modes of the WC camera mechanism. The WC camera provided a range of viewing positions from the front of the WC at eye level to more than 2 ft in front of the WC user's knees at waist level. The solutions to expand visibility of WC users have not been adequately addressed in previous investigations in wheeled mobility.