Design, Construction, and Experimental Evaluation of a Monopropellant Powered Free Piston Hydraulic Pump

Abstract

A monopropellant powered free piston hydraulic pump (FPHP) was designed as a human scale (1.0 to 3.0 kW) mobile robotics power supply. The FPHP utilized high concentration hydrogen peroxide, which decomposes into hot gas when exposed to a catalyst, as the monopropellant energy source. Energy was extracted from the hydrogen peroxide and transferred directly to hydraulic fluid by expanding the hot decomposition gas in an integrated piston/cylinder arrangement. The prototype FPHP successfully produced 50 W of hydraulic power by pumping hydraulic fluid at an average pressure of 6.5 MPa (940 psi) and flow rate of 0.48 liters/min (0.13 gallons/min).