Digital micropropulsion

Arrays of "Digital Propulsion" microthrusters have been fabricated and test ed. A three-layer sandwich is fabricated containing microresistors, thrust chambers, and rupture diaphragms. A propellant is loaded into each individu ally sealed chamber. When the resistor is energized, the propellant ignites , raising the pressure in the chamber and rupturing the diaphragm. An impul se is imparted as the high-pressure fluid is expelled from the chamber. On the order of 10(6) thrusters can be fabricated on a single wafer. Initial t ests, using lead styphnate as the propellant, have produced 10(-4) N s of i mpulse and about 100 W of power. (C) 2000 Elsevier Science S.A. All rights reserved.