A Low Noise Thrust Stand for Micronewton Thrust Measurements Based on a Parallelogram Mechanism

In the field of gravitational wave detection, micro thrusters are used to compensate for environmental disturbances. The resolution of the thrust stand typically needs to meet micronewton specifications with sufficiently low background noise. Presently, significant progress has been made in research concerning thrust resolution. However, it remains an ongoing challenge to measure thrust precisely while maintaining low noise levels. In this paper, a novel parallelogram mechanism thrust stand (PMTS) is proposed, leveraging its insensitivity to non-thrust direction moments to achieve precise thrust measurements with low noise. The theoretical model for steady-state thrust and the stiffness model of the PMTS are established. The typical responses of the PMTS under different force loading conditions are tested. In addition, the thrusts of a cold gas thruster and a Hall micro thruster are tested in a high-vacuum environment. The experimental results show that the resolution of the PMTS is 80 nN, while background noise is better than 0.1 μN/Hz<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1/2</sup> above 0.6 mHz.