Energy regenerative hose-free pneumatic actuator

• An energy-regeneration cycle for the actuator driven with water-electrolysis/synthesis is proposed.
• The energy consumptions for with/without the energy-regeneration are theoretically derived and the improvements are shown.
• As the experimental result, the power consumption is reduced by about 20%, which agrees well with the theoretical result.
• An air-supply-hose-free pneumatic rubber actuator works well with the response time of about 5.7 s.

Pneumatic actuators in general require an air-compressor, valves, and pneumatic hoses. This makes them difficult to be used on mobile apparatus. To solve this problem, we previously developed a new gas source that uses the electrolysis/synthesis of water through an ion-exchange membrane. The developed gas source uses a gas/liquid reversible chemical reaction and controls the generation/absorption of gas through an electric current supplied to the membrane.In this paper, we present a control method for the energy-regeneration cycle and perform theoretical and experimental studies to verify its power consumption. This energy-regeneration control method is applied to an actuator, and it works successfully with a power consumption improvement of approximately 20% compared to that without energy-regeneration. Furthermore, we successfully develop a hose-free pneumatic rubber actuator with this control method.