Fast And Stable Control Methodresearch Of Flexible Satellite Attitude

At present, as the spacecraft launched by our country mostly with flexible appendages, flexible appendage is moving towards a more complex structure and volume of the trend, but also to control the spacecraft requirements have become more and more strict, the control algorithm we used shall meet the requirements of flexible spacecraft with rapid maneuver, fast and stable demand. The new control demand is reflected in two aspects: first, the spacecraft for flexible appendage is becoming more and more complicated, leading to model uncertainty increases, the control system needs to adapt to the uncertainty of the controlled object; second, with large flexible appendages maneuver spacecraft in the fast speed and stability, control the quality needed to be improved.This paper addresses the control problem more flexible space paper flexible satellite itself there are modal frequency uncertainty, the flexible satellite control system design of the composite control algorithm of PD and EI to reduce the vibration of flexible devices, and avoid the mode of flexible components of the direct detection of difficulties and the observer design and increase the system complexity problem.First, determine the PD output feedback controller for dynamic object, elaborate the design parameters of the controller, the attitude control system has good dynamic quality; in addition, in order to suppress the vibration of flexible structure, further the EI input shaping vibration suppression method is introduced to the outside of the closed-loop control system, in order to change the input command to suppress the vibration shape the purpose of flexible structure; then according to the modal frequency and system inertia uncertainty variable structure controller is designed based on RBF neural network adaptive, and introduces the method of inhibiting EI input shaping vibration, to change the input command shape to weaken the vibration of the structure, simulation results verify the design theory and the research method is feasible and accurate.Secondly, aiming at the flexible satellite large angle attitude maneuver in, modal vibration suppression problem of aircraft with saturation generated, using component synthesis and feedback control of a combination, a method for component synthesis of saturation characteristics to suppress the vibration of the flexible body design, improve the attitude maneuver settling time and steady-state accuracy. Can be seen from the simulation results, aimed at restraining the modal vibration actuator with saturable nonlinearity, using the PD control with the component synthesis active vibration suppression method can effectively reduce the vibration modal, shortening stable time, improve the steady-state accuracy, the method of modal frequency variation range is robust under the condition of 20%.