Microelectromechanical systems(MEMS) techniques offer greatpotential in satisfying the mission requirements for the nextgeneration of miniaturized spacecraft being designed by NASAand Department of Defense agencies. More commonly referred toas `nanosats', these spacecraft feature masses in the rangeof 10-100kg and therefore have unique propulsion requirements.The propulsion systems must be capable of providing extremelylow levels of thrust and impulse while also satisfyingstringent demands on size, mass, power consumption and cost. Webegin with an overview of micropropulsion requirements and somecurrent MEMS-based strategies being developed to meet theseneeds. The remainder of the paper focuses on the progress beingmade at NASA Goddard Space Flight Center toward the developmentof a prototype monopropellant MEMS thruster which uses thecatalyzed chemical decomposition of high-concentration hydrogenperoxide as a propulsion mechanism. The products ofdecomposition are delivered to a microscaleconverging/diverging supersonic nozzle, which produces the thrustvector; the targeted thrust level is approximately 500µN witha specific impulse of 140-180s. Macroscale hydrogenperoxide thrusters have been used for satellite propulsion fordecades; however, the implementation of traditional thrusterdesigns on the MEMS scale has uncovered new challenges infabrication, materials compatibility, and combustion andhydrodynamic modeling. A summary of the achievements of theproject to date is given, as is a discussion of remainingchallenges and future prospects
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