A torsional thrust stand for electric propulsion thruster

A torsional thrust stand with heavy load and stability has been developed for electric propulsion thruster testing under vacuum conditions. The thrust measurement principle is based on torsional pendulum mechanics combined with capacitive displacement sensing. The stand features a closed loop and non-contact capacitive detection to achieve a resolution of 0.1 mN within a measurement range up to 100 mN, with experimental validation conducted at the 5 mN level. Calibration was performed using two separate approaches: one based on electromagnetic force detection and another based on gravitational mass measurements, and experimental validation was conducted using an ion thruster under a vacuum of 10−4 Pa. The results demonstrate that the stand achieves stable and accurate thrust measurement, providing an effective tool for performance evaluation of submillinewton- and low-thrust electric propulsion systems.