An overview of MEMS-based micropropulsion developments at JPL

Development of MEMS (Microelectromechanical Systems) micropropulsion at the Jet Propulsion Laboratory (JPL) is reviewed. This includes a vaporizing liquid micro-thruster for microspacecraft attitude control, a micro-ion engine for microspacecraft primary propulsion or large spacecraft fine attitude control, as well as several valve studies, including a solenoid valve studied in collaboration with Moog Space Products Division, and a piezoelectric micro-valve. The solenoid valve features much faster actuation (as little as 1.5 ms to open) than commercially available MEMS valves and showed no detectable leak (< 10^-4 sccs GN₂) even after 1 million cycles. The solenoid valve weighs 7 gram and is about 1 cm³. A micro-isolation valve, aimed at sealing propulsion systems at zero leak rates, was able to show burst pressures as high as 3,000 psi even though entirely machined from silicon and Pyrex. It could be actuated with energies as little as 0.1 mJ.