Because of the elderly society in Japan, a passive exercise device that can be used in homes or hospitals without assistance is desirable. In the device, a soft actuator that can move with both longer strokes and a larger force is useful. In the previous study, a pneumatic linear stepping actuator (PLSA) that can push and pull a flexible rod while changing the gripping position of a tube was developed. In this study, a variable step type PLSA is proposed and tested. Moreover, the development of a passive exercise device for the hip joint using three PLSAs and one connecter connected with three flexible rods and a knee supporter is described. The tracking position control of the knee supporter based on an analytical model is also described. The control system using developed actuators is also introduced.
Research papers (academic journals)
