Hose-free pneumatic bags-muscle driven by gas/liquid conversion

Pneumatic artificial muscles have unique advantages such as high compliance, high ratio of power to mass, and easy manufacturing. These advantages are different characteristics from electric motors and hydraulic actuators, therefore pneumatic artificial muscles are expected to be applied to new robotic systems such as muscle suits and exploration robots. On the other hand, they require an air compressor, valves, and air supply hoses, making the multi DOF pneumatic robot systems large and complicated. In existing studies, we proposed a novel driving principle that does not require air compressors, valves, nor air supply hoses. Its actuation was based on the reversible chemical reaction of water electrolysis/synthesis using a polymer electrolyte fuel cell (PEFC). In this paper, we demonstrate a pneumatic artificial muscle which can be driven without air supply hoses, by applying the principle mentioned above to a bags-muscle which is a plastic pneumatic artificial muscle. The results of the driving experiments show that the proposed pneumatic artificial muscle can be successfully controlled by electric current.