Robust coordinated control for large flexible spacecraft based on consensus theory

A distributed coordinated robust control method is proposed in this paper for large flexible spacecraft with distributed actuators and sensors. By dividing the control framework into an attitude dynamic system and a structural vibration system, a consensus observer is designed to estimate the primary system's modal coordinates and the graph theory is used to develop a leader-follower consensus vibration controller to reduce the oscillation of the flexible structures. The robust optimal attitude controller with known averaged vibration modal parameters is also designed to overcome the influence of environmental disturbances and other system uncertainties. The integrated result is an effective pointing controller of large flexible spacecraft, which is also robust to failures and inconsistencies in the control system. A comparative study is presented to show the advantage of the decentralized design over the conventional centralized method. Simulation results are provided to demonstrate the performance of the proposed control method. (C) 2020 The Franklin Institute. Published by Elsevier Ltd. All rights reserved.