An obstacle avoidance system for an electric wheelchair

It has been suggested by wheelchair users that an obstacle avoidance system might be a useful accessory for an electric wheelchair. This paper examines the performance requirements of such a system, and discusses the range sensing techniques that could be used. Range sensing systems considered include ultrasonic, vision, and active light, of which ultrasonic and active light were selected for further investigation. Ultrasonic systems have been found insufficiently reliable in the detection of obstacles to be of use as the only range sensing system. An infrared light emitting diode triangulation system is under development, which seems to hold the potential for satisfactory performance at reasonable cost