Pinpointed muscle force control using a power-assisting device: System configuration and experiment

The demand for rehabilitation robots is increasing for the upcoming aging society. Power-assisting devices are considered promising for enhancing the mobility of elderly and disabled people. Other potential applications are for muscle rehabilitation and sports training. The main focus of this paper is to control the load of selected muscles by using a power-assisting device, thus enabling ldquopinpointedrdquo motion support, rehabilitation, and training by explicitly specifying the target muscles. By taking into account the physical interaction between human muscle forces and actuator driving forces during power-assisting, the feasibility of this muscle force control is analyzed as a constrained optimization problem. A prototype power-assisting device driven by pneumatic rubber actuators is developed. A control system is developed with a graphical user interface that provides an easy operation to designate desired forces for target muscles. The validity of the method is confirmed by experiments by measuring surface electromyographic (EMG) signals for target muscles.