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This work studies the maneuver control and vibration suppression of a flexible free-flying space robot using variable-speed control moment gyros as actuators. A novel flexible space manipulator is designed. The dynamics of the flexible multibody system is derived by using Kane method. Based on the singular perturbation approach, the dynamics of the flexible manipulator is decoupled into a slow subsystem and a fast subsystem. The slow subsystem is associated with the rigid motion dynamics, and the fast subsystem is related to the link flexible dynamics. A composite control strategy is proposed as a combination of two controllers for these subsystems. An adaptive sliding mode controller is designed for the slow subsystem, and an adaptive controller is designed for the fast subsystem. Uncertainty estimation can be achieved by the adaptive terms of the composite controller. A weighted robust pseudo-inverse steering law is proposed for the variable-speed control moment gyros. Numerical results demonstrate that the proposed composite controller is robust to parameter uncertainties and external disturbances. [ABSTRACT FROM AUTHOR]

With the development of the space station technology in China, the active vibration suppression of the lager flexible antennas and solar panels that mounted on the space station is demanded. The active vibration suppression is hard to achieve because these appendages are not allowed to mount actuators on it. Further, the practical goal is usually unachievable by the controller based on the unreliability or impracticality observed vibration parameters. In this paper, the active vibration suppression during the spacecraft attitude maneuver by the optical camera monitoring the dynamic behaviors of the flexible appendages is introduced under the restriction of the freedom of the actuators. The modal parameters of the flexible appendage used in the controller are obtained by the optical monitoring approach. A referenced angular velocity is set as the virtual input by the back-stepping control and Lyapunov method, and the control law is designed to track this virtual input. The constraint of the coefficient in the controller is investigated to guarantee the asymptotic convergence of the system considering angular velocity tracking error. The control manage coefficient is defined to describe the distribution coefficient of the vibration suppression in the design of control law. The relationship between the attitude maneuver accuracy and active vibration suppression is introduced. The appropriate control manage coefficient is obtained numerically. To guarantee the reliability or practicality of the designate flexible spacecraft control system, the optical measurements are used to measure the dynamic behaviors of the large flexible structures. The absence of displacement velocity sensors is compensated by the presence of appropriate dynamics in the controller. The results of simulation validate the feasibility of the proposed control strategy. [ABSTRACT FROM AUTHOR]