A PREDICTION METHOD FOR THE INTERFACE PROFILE OF SPACE HINGE MECHANISMS WITH CLEARANCE CONSIDERING WEAR–DYNAMICS COUPLING

To address the problem of wear-dynamics coupling failure in revolute clearance joints during long-term service of spacecraft in microgravity environments, this study proposes a cross-scale wear prediction method using a revolute clearance joint-containing crank-rocker mechanism as the research subject. First, a general framework for cross-scale wear-dynamics coupling prediction was established, elucidating the coupled evolution process between macroscopic system dynamics and microscopic interface damage. Second, a coupled simulation model of the revolute clearance joint was developed using multi-body dynamics and finite element methods to obtain the transient dynamic characteristics of the hinge interface; a cyclic jump acceleration algorithm was introduced to overcome the computational bottleneck associated with long-duration simulations. Furthermore, a micro-scale wear model for the hinge interface was developed based on the modified Archard theory, and the parameters of the equivalent comprehensive wear coefficient for the TC4 titanium alloy interface were identified through ground-based vacuum microgravity simulation experiments. By coupling the dynamic model with finite element wear calculations, a wear profile prediction model for the hinge interface was established that accounts for transient impact characteristics. Finally, using independent experimental samples as case studies, the failure wear profiles of hinges under full-lifetime operating conditions were predicted and validated. The study revealed a positive-feedback failure mechanism characterized by “off-center impact - fatigue spalling - gap expansion - kinetic energy accumulation,” providing theoretical support for the in-orbit wear-resistant design and life assessment of space mechanisms.