Optimized Design and Experimental Analysis of Mechanical Structure of Torsional Pendulum Thrust Frame

China enters the era of large-scale application of plasma propulsion in 2020, and there is an urgent demand for electric propulsion technology in the fields of human spaceflight, communication constellation, deep space exploration, and space science. Thrust is one of the key performance indicators of electric propulsion systems. Accurate and reliable measurement of thrust is the basis for performance testing and optimization of electric propulsion systems. Currently, 10∼100-mN electric propulsion systems are the most widely used. In this paper, a mechanical structure model of a 10∼100-mN torsional pendulum thrust frame is proven using the lever principle, the deflection performance under different thrusts is studied, and the linear relationship between deflection displacement and thrust is derived. The ANSYS simulation software was used to perfect the simulation analysis of each design variable. The influence of each parameter is investigated by experiment. The results show that the optimized torsional pendulum thrust frame structure has good linearity, and the relative error is better than 0.33%.