Dynamics analysis, experimental validation and attitude control of a complete satellite with clearance joints considering solid lubrication

The attitude stability of high-precision satellites is significantly affected by the coupled effects of flexible appendages and joint clearances under thermal environments. However, the influence of solid lubrication coatings and experimental validation are rarely considered in existing studies. This paper develops a rigid-flexible-thermal coupling multibody dynamics model for a complete satellite system, integrating the Absolute Nodal Coordinate Formulation (ANCF), Natural Coordinate Formulation (NCF), and a solid-lubricated clearance joint contact model. The results reveal that solid lubrication coatings can effectively reduce contact forces, but softer materials may increase collision frequency and introduce high-frequency disturbances. MoS 2 exhibits superior contact mitigation performance and stability. To suppress the nonlinear disturbances induced by clearance and lubrication effects, a sliding mode robust controller based on a reaching law is designed, which significantly improves system stability. The proposed model is experimentally validated through modal testing, showing good agreement with simulation results. The structural dynamics formulation is validated through modal testing of the flexible solar panel substructure, while the remaining components are established using well-validated theoretical models. The proposed framework provides practical guidance for improving the attitude stability of high-precision satellites.