Dynamics modeling and attitude-vibration hybrid control of a large flexible space structure

Abstract

The challenges in the dynamic modeling and control of large flexible space structures (LFSSs) include the high number of degrees of freedom in the model, the geometric nonlinearities in the flexible components, and the nonlinear coupling effects between overall motions and vibrations of the structure. In this study, we propose a systematic method to solve the mentioned problems in the research of LFSSs. We use the referenced nodal coordinate formulation (RNCF) to build the dynamic model. The modeling method is general and the model can better describe the large deformations of flexible structures compared with the modal-based dynamic model. The key feature of our work is that we use a hybrid control strategy for the attitude and vibration control directly performing on the full-scale dynamic model. Specifically, the control strategy combines a proportional and derivative (PD) control algorithm based on SO(3) for the attitude control and an analytical linear-quadratic (LQ) vibration control method for the vibration control. The simulation results are presented to demonstrate the effectiveness of the proposed hybrid control strategy both in the three-axis attitude maneuver task and on-orbit pointing scenario.