Colloid Microthrust Propulsion for the Space Technology 7 (ST7) and LISA Missions

Abstract

For future applications to precision formation flying missions, NASA’s New Millennium Program is scheduled to test Colloid Micro‐Newton Thrusters (CMNTs) on the ST7 technology demonstration mission. These CMNTs are part of a disturbance reduction system (DRS) on the ESA SMART‐2 Spacecraft or LISA Pathfinder. The goal of the ST7 DRS is to demonstrate technologies necessary to meet the nanometer precision positioning control requirements of the LISA mission. In order to achieve these goals, the CMNTs are required to demonstrate a thrust resolution of less than 0.1 μN and a thrust noise of less than 0.1 μN/√Hz for thrust levels between 5 and 30 μN. Developed by Busek Co. with support from JPL in testing and design, the CMNT has been developed over the last four years into a flight‐ready microthrust system. The development, validation testing, and flight unit production of the CMNTs are described. Development tests and analysis include preliminary wear tests, propellant loading process verification, flow testing, and performance verification. Validation and flight unit verification includes thermal and structural analysis, life testing, thermal and dynamic load testing, and performance verification. Final delivery of the units is planned in 2007 with and planned launch and flight demonstration 2009.