Research on Collision Simulation and Control Strategies for Test Mass Release under Electrostatic Control

Space inertial sensors are crucial for space-based gravitational wave detection, requiring precise injection of test masses (TMs) into geodesic trajectories. However, conventional electrostatic suspension methods face challenges in capturing TMs with momentum exceeding 1×10 -5 kgm/s. This study proposes a novel approach to mitigate TM release momentum by leveraging controlled collisions between the locking and release mechanism and the TM. A multi-body collision dynamics model, developed in MATLAB/Simulink, simulates the in-orbit injection process under space conditions, integrating low-speed collision contact detection and electrostatic interactions. The improved injection scheme employs momentum attenuation through plunger-TM collisions and utilizes electrostatic forces for orientation control, effectively expanding the allowable momentum range during release. Simulation results demonstrate that the strategy reduces TM momentum to capturable levels of <5 μm/s linear velocity and <150 μrad/s angular velocity within 300 seconds, even under non-ideal initial conditions. The collision-based method enhances injection reliability by addressing adhesion risks and momentum uncertainties, offering a robust solution for future gravitational wave detection missions.