Abstract: This paper addresses the integrated attitude-vibration control and torque allocation problem for a plate-type flexible spacecraft equipped with a distributed array of variable-speed double-gimbal control moment gyroscopes. A hierarchical control architecture combining sliding-mode control and linear quadratic regulator (LQR), together with an optimized torque allocation strategy that coordinates modal excitation and mitigates mutual interference between vibration suppression and attitude maneuvers, is proposed based on singular perturbation theory. First, the coupled attitude-structural dynamics are decomposed via singular perturbation into a slow-varying attitude subsystem and a fast-varying vibration subsystem. A sliding-mode controller is designed for the slow subsystem to achieve robust attitude control, while an LQR-based vibration suppressor is developed for the fast subsystem. Crucially, the parasitic disturbance induced by vibration-suppression torques on the attitude dynamics is explicitly compensated in the control law. Building upon this, a torque allocation model formulated as a quadratic programming problem is established by analyzing the excitation effect of attitude maneuver torques on the modal space and their interaction with vibration-suppression torques. The objective function simultaneously minimizes modal excitation and interference with active vibration control. Furthermore, an adaptive weighting scheme, dependent on the mechanical energy of structural vibrations, is introduced to dynamically balance these two objectives. Numerical simulations demonstrate that, compared to a uniform torque distribution scheme, the proposed optimization-based allocation method reduces the peak structural deformation by 79.13%, while maintaining high-precision attitude maneuvers (with maximum quaternion error on the order of 10-4). These results confirm the significant enhancement in integrated attitude–vibration control performance for large-scale flexible space structures.

Key words: large space structure, gyroelastic structure, control moment gyroscopes, singular perturbation method, Toque distribution