Next generation autonomous wheelchair control

Often times the physically challenged, limited to a wheelchair, also have difficulty with vision. In order to help, something must "see" for them. Therefore there must be some way for a wheelchair to know its environment, sense where it is, and where it must go. It also must be able to avoid any obstacles which are not normally part of the environment. An autonomous wheelchair will serve an important role by allowing users more freedom and independence. This design challenge is broken into four major steps: wheelchair control, environment recognition, route planning, and obstacle avoidance. The first step is to reverse engineer a wheelchair and rebuild the controls, which will be the main topic of discussion for this paper. Two big challenges with this step are high power motor control and joystick control. An H-bridge motor interface, controlled by a microprocessor, was designed for the motors. The joystick control is handled with the same microprocessor.