Impulse Measurement Methods for Space Micro-Propulsion Systems

Abstract

Space micro-propulsion systems are increasingly considered an attractive option for station-keeping and drag-makeup purposes for the mass- and power-limited satellites due to their critical factors of simple design, small volume, and high specific impulse. These systems typically generate low-range thrust from nN to mN, and their impulses are less than mNs, making it difficult for conventional sensors to detect them directly. Consequently, the design of a special thrust stand is often necessary to measure these micro-propulsion systems. This chapter outlines recommended practices for the operation and calibration of three conventional measurement methods, along with the introduction of an impulse measurement stand developed at the National University of Defense Technology. The chapter presents the fundamentals, calibration method, and experimental results of the stand operation, while also analyzing error sources. Finally, the chapter discusses the demand and direction of micro-impulse measurement development.