Development and preliminary testing of MOVit: An exercise-enabling control interface for power wheelchair users
Power wheelchair users have a high level of sedentarism, which negatively impacts health. If they could exercise while driving their chair they could potentially improve their health through integrated daily exercise. This dissertation presents the development of MOVit, a novel, arm exercise-enabling, wheelchair control interface and the results of three preliminary tests with unimpaired subjects. MOVit consists of two custom-made, instrumented mobile arm supports that replace the armrests of a normal power wheelchair. Instead of using a joystick to drive the wheelchair, the user moves the arm supports with his or her arms through a cyclical motion. MOVit was first tested in a stationary setting with five healthy individuals (two expert users and three naïve users) to determine if they could achieve increasing levels of exercise by increasing the frequency and range of motion of arm movement, and decreasing the amount of weight support. Secondly, driving performance using MOVit was evaluated with the same subjects on a long, straight track. Third, maneuverability with MOVit was evaluated for the expert users. Heart rate and oxygen consumption significantly increased as the level of exercise intensity increased in the stationary setting. Driving performance for the long, straight track and for the maneuverability test were comparable to the performance achieved using a standard joystick for the two expert users, but was worse for the three novice users. In conclusion, MOVit can modulate exercise intensity during power wheelchair driving. For experienced users, driving performance and maneuverability is comparable to that achieved with a standard joystick.