Design and Energetic Characterization of a Proportional-Injector Monopropellant-Powered Actuator

Abstract—This paper describes the design and energetic char-acterization of an actuator designed to provide enhanced system energy and power density for self-powered robots. The proposed actuator is similar to a typical compressible gas fluid-powered ac-tuator, but pressurizes the respective cylinder chambers via a pair of proportional injector valves, which control the flow of a liquid monopropellant through a pair of catalyst packs and into the re-spective sides of the double-acting cylinder. This paper describes the design of the proportional injection valves and describes the structure of a force controller for the actuator. Finally, an ener-getic characterization of the actuator shows improvement relative to prior configurations and marked improvement relative to state-of-the-art batteries and motors. Index Terms—Energetic characterization, monopropellant-powered actuation, power-autonomous robots