Mechanisms and Applications of Conductive Wear Debris Motion under Coupled Microgravity and Multi-Physics Electromagnetic Environments

The Solar Array Drive Assembly (SADA) and the Control Moment Gyroscope (CMG) are core components for power transmission and attitude control in spacecraft. During long-term operation, conductive wear debris is inevitably generated within the assembly. Under the combined effects of microgravity and multiple physical fields, this debris tends to aggregate, thereby increasing the risk of internal arcing and breakdown, which may ultimately lead to spacecraft failures. This study develops a theoretical model describing the behavior of conductive wear debris under the coupling of microgravity and multi-physics fields. The dynamic characteristics and accumulation mechanisms of conductive debris within the SADA are systematically investigated. To establish the dynamic model of conductive debris, this work first constructs several physical field models. Based on these models, the dynamics equations of debris under microgravity are derived. Numerical simulations are then performed to analyze debris trajectories under various initial conditions. The results indicate that the electric field force is the dominant factor influencing debris motion. Under its influence, the debris migrates toward the outer wall of the slip ring, where it eventually forms an accumulation layer.