Time-dependent kinematic reliability of a dual-axis driving mechanism for satellite antenna considering non-uniform planar revolute joint clearance

Abstract

The dual-axis driving mechanism is a key part of satellite antenna. It is required to operate for millions of motion cycles in space. Wear is inevitable in the joints, which makes the clearance non-uniform. However, the investigations regarding this issue are quite limited. In this study, we conduct time-dependent kinematic reliability analysis for the dual-axis driving mechanism with non-uniform joint clearance. Firstly, an efficient wear prediction method is proposed under the framework of multi-body dynamics. Then, the position error model is established considering non-uniform joint clearance, input uncertainty, and linkage dimension error. On this basis, the mean and covariance matrix are analytically determined for the joint distribution of the position error along x, y, and z axes. The envelopes of the position error functions are derived. Finally, the time-dependent kinematic reliability is estimated with the integration of a multivariable normal distribution at the calculated expansion points. The effectiveness of the proposed method is validated by comparison with the Monte Carlo simulation.