An anti-disturbance PD control scheme for attitude control and stabilization of flexible spacecrafts

Abstract

This paper studies the attitude control problem of spacecrafts with flexible appendages. It is well known that the unwanted vibration modes, model uncertainty and space environmental disturbances may cause degradation of the performance of attitude control systems for a flexible spacecraft. In this paper, the vibration from flexible appendages is modeled as a derivative-bounded disturbance to the attitude control system of the rigid hub. A disturbance-observer-based control (DOBC) is formulated for feedforward compensation of the elastic vibration. The model uncertainty and space environmental disturbances as well as other noises are merged into an "equivalent" disturbance. We design a composite controller with a hierarchical architecture by combining DOBC and PD control, where DOBC is used to reject the vibration effect from the flexible appendages. Numerical simulations are performed to demonstrate that by using the composite hierarchical control law, disturbances can be effectively attenuated and the robust dynamic performances be enhanced.

Free-flying dynamics and control of an astronaut assistant robot based on fuzzy sliding mode algorithm

“…According to the coordinate transformation matrix standard formula, the attitude transformation matrix that the reference coordinate system to the body coordinate system can be derived as [15]:…”

Anti-Unwinding Attitude Control with Fixed-Time Convergence for a Flexible Spacecraft

“…These factors make the design of an attitude control law with rapid and precise maneuver performance for a flexible spacecraft very difficult and even pose a great challenge to space missions. In recent years, a variety of control methods have been proposed to solve the attitude control problem, like proportional derivative control [1], adaptive control [2], ∞ control [3], passivity-based control [4,5], sliding mode control [6][7][8], active disturbance rejection control [9], disturbance observer based control [10], and so forth [11][12][13]. Although these nonlinear control laws have offered sufficient and reliable effectiveness and robustness in spacecraft attitude control systems, they require infinite time to accomplish an attitude maneuver.…”

Robust fault-tolerant control for flexible spacecraft against partial actuator failures

“…It is because modern spacecraft often employ large, deployed and light damping structures (such as solar paddles and antenna reflectors) to provide sufficient power supply and reduce launch costs [1][2][3][4][5][6]. During the control of the rigid body attitude, actuators play an important role of linking control commands to physical actions [7,8]. Normally, the actuators should execute commands demanded by the controller faithfully and completely.…”

“…On the other hand, the complex space structure may lead to the decreased rigidity and low-frequency elastic modes. However, elastic vibration of the flexible appendages may cause degradation of the performance of attitude control [7,11]. Thus, the desired control scheme should tolerate partial loss of actuator effectiveness and be robust enough to overcome various disturbances from structural vibrations of the flexible appendages.…”