Reconstruction of wear debris migration trajectory and analysis of motion characteristics in on-orbit spacecraft conductive slip rings

Abstract

The electrically charged wear debris generated inside the conductive slip ring of spacecraft not only exacerbates the wear of the ring channel but also causes distortion of the electric field, which can induce surface flashover in vacuum, seriously affecting the operational reliability of solar array panels. This study is based on the space station experimental cabin’s on-orbit technology testing platform, and it systematically investigates the wear debris migration behavior of the brush–slip ring mechanism. Through long-term on-orbit testing observations, a three-dimensional multiphysics coupling model was developed using a Monte Carlo-Finite Element joint algorithm. This model reveals the migration mechanism of wear debris under the combined effect of the electrostatic field and electron radiation field: debris without initial velocity primarily adheres to the metal ring surface; debris with initial velocity migrates towards the shield with a speed of up to 0.0136 m/s in the electrostatic field, while a small amount adheres to the side of the insulating baffle due to electric field distortion near the brush; under the electron radiation combined field, the surface potential reconstruction of the dielectric increases the local field strength to 2.2 × 10⁸ V/m, significantly enhancing the migration trend of the debris towards the insulating baffle and causing the debris on the inner side of the shield to detach and impact the baffle. The study accurately reproduced the spatial distribution characteristics of the wear debris and revealed the discharge behavior induced by the debris through trajectory prediction models and comparison with on-orbit experimental data. This provides theoretical support for the insulation reliability design of space electromechanical products.