Development of electric cart for improving walking ability - application of control theory to assistive technology
She, Jinhua; Ohyama, Yasuhiro; Wu, Min; Hashimoto, Hiroshi
Sci China Inf Sci, 2017, 60(12): 123201
This paper explains the development of an electric cart that helps the elderly maintain or improve their physical strength. Unlike commercially available ones, it has a pedal unit that provides some exercise for a user in training his lower limbs. An impedance model describes the feeling of pushing the pedals. The largest pedal load is determined based on a pedaling experiment. An H∞ controller is designed for each of the largest pedal load and virtually no load. A control law, which is based on the concept of dynamic parallel distributed compensation, is designed using the rating of perceived exertion of a driver as a criterion to choose a pedal load between the largest and almost zero. Five university students and twelve elderly people articipated experiments to verify the system design and the validity of the system.