Use of a treadmill for rehabilitation with active impedance control

Ambulatory capability is necessary for the self-support of the aged. Therefore we proposed the walk training system for walk rehabilitation. A walk training system for the aged is now under development. It has two parts: a training environment and a patient support element. The training environment comprises a treadmill and a display. In this paper, the control method, parameter estimation and experiments are described. We introduced a new control method for a treadmill of the walk training system, which uses active impedance control. The velocity of the treadmill is changed by kicking force from a trainee on the treadmill. Thus a trainee can walk at a speed which he can cope with. The treadmill has two endless belts driven by servo motors, one for each of the trainee's legs. Thus, the trainee can use the treadmill even if his or her two legs are not of equal ability, for example a post-stroke hemiplegia.