Semi-autonomous mobility assistance for power wheelchair users navigating crowded environments.

Power wheelchair users suffering from cognitive or physical impairment often face difficulties in maneuvering their wheelchairs through crowded environments. Currently, users need to be continuously aware of all traffic around them to actively avoid all collisions. This is an especially difficult task since many wheelchair users are unable to accurately view or perceive their surroundings. Additionally, imprecise joystick control, slowed reaction time, or imperfect interpretation of the environment can lead to unintended collisions with objects in the environment. This work looks to augment user's input with data gathered from an ultrasonic sensor ring to prevent accidental collisions. Using data gathered from the sensors, we detect objects within a certain radius of the chair. This sensor information is combined with the user input from a joystick to generate a potential field description for the intended motion of the wheelchair. An optimal motion vector is calculated which works to avoid collision with obstacles. Ultimately, this control method reduces the cognitive load on the user and enables them to navigate complex environments by providing simple and/or imprecise input to the system.