NASA’s Jet Propulsion Laboratory, Pasadena, California
A micro-electrofluidic-spray propulsion (MEP) system was built on a micro scale, in which arrays of hundreds of nano-thrusters are etched on silicon wafers like ICs, only a centimeter on a side. Many dozens of these thruster chips can be arrayed to form a macro-thruster of finite and significant thrust. Approximately 300 centimeter-square, 100-micro-Newton micro-thrusters are arrayed in a square pyramidal structure. The pyramid is of shallow obliquity, with no more than 20° offset from the spacecraft face. This small angular offset is sufficient to provide thrust vector control (TVC) for the thruster.
With the MEP thruster, the main mission thrusting, TVC, and even spacecraft attitude control can be accomplished in a single, small, compact, and efficient unit. MEP is infinitely scalable. As many or as few micro-thruster chips can be assembled as necessary into a thruster cluster. As applied to a large mass carried to Mars, this approach to providing propulsion could reduce the necessary launches for the propulsion system of a modest-sized human mission from ten heavy launches to one.