Performance improvement of a six-degree-of-freedom elastic pendulum thrust stand for micropropulsion

This study presents the design and performance evaluation of an updated six-degree-of-freedom elastic pendulum thrust stand with enhanced measurement capabilities. The thrust stand is designed to measure all thrust and torque components, which are critical for advanced missions utilizing miniature propulsion systems. Key enhancements include the integration of high-resolution electrostatic capacitive displacement sensors and the expansion of measurable test targets. The thrust stand employs a null-balance method and was successfully demonstrated with a few mN-class cold-gas thruster. The results showed significant improvements in measurement resolution, with uncertainties of thrust vector components within 0.13 mN and those of torque components within 0.028 mN $$\cdot$$ m for a 4 mN thrust level. This research aims to establish a practical and versatile six-degree-of-freedom measurement system applicable to a wide range of propulsion systems, including electric propulsion systems.