Micro-Thrust Measurement of a MEMS Based Cold Gas Micro-Thruster in Vacuum Conditions

As the development of micro/nano-satellites and strong demand of micro-propulsion system, the micro-thrust measurement attracted increasing attention, especially over the efficiency, automation and accuracy aspect. In this paper, an automatic micro-thrust measurement system and propellant supply system in man-made vacuum environment have been designed. Then, nine groups of N2 cold gas micro-thruster have been tested in this system. The system error and data processing method have been analyzed for chasing the accuracy result. The experimental results show that the performance of the micro-thruster is optimal when the half-convergence angle is 30 degrees, the half-expansion angle is 30 degrees and the area ratio is 4. The special impulse is 34.67s and thrust force is 20.80mN under input pressure 2.83bar. The results are helpful to understand flow characteristics of micro-thruster and improve its performance. Besides, this micro-thrust force measurement system and signal batch processing method are proved to be feasible and high efficiency.