Research On Modeling And Control Of Flexiabe Spacecraft

This paper deals with a kind of spacecraft consisting of a ragid platform and two identical flexible appendages, with the dynamics models, coupling analysis and attitude control of the flexible spacecraft being investigated. The aim of this paper is to suppress the flexible vibration during attitude maneuvering.This paper mainly concerns with the followings:1. The flexible spacecraft with a rigid platform and two identical flexible appendages is modeled by hybrid coordinate method and Lagrange theory. A simplified model is presented for controller designing. And the coupling characteristic is analyzed.2. The stability of the restrained Variable Structure Controller is discussed. A Fuzzy Variable Structure Controller is designed with Fuzzy Control being introdued to suppress chattering. At last, simulations are presented.3. Based on the attitude control of the flexible spacecraft, this paper prompts a method to change nonlinear state equations to T-S fuzzy model. A kind of control strategy is proposed based on PDC fuzzy controller and pole placement method. At last, simulations are presented.4. Explore the use of the intellegent material in the fields of flexible spacecraft vibration control. The intellegent material is extended to the flexible spacecraft system dynamics equations. Based on the established system equations, two kinds of controller is designed involving Fuzzy Control theory, Variable Structure Control theory and direct velocity feedback control method. At last, simulations are presented.5. About the large deformation description, a multi-floating coordinate system is adopted. It can effectively reduce the error of discretization.This paper deals with the design of restrained Variable Structure Control in the way of phase plane analyse, which is concise and avoids complex mathematical descriptions.A new method is promoted for flexible spacecraft control by describing flexible spacecraft dynamics equations as T-S fuzzy model and designing a PDC fuzzy controller. Simulations show that, the controller suppresses the flexible vibration during attitude maneuvering and the control strategy turns out to be intelligent. The flexible spacecraft with intelligent material is modeld and related control strategies are explored. The simulation platform integrates MATLAB 7.0(Simulink) and Visual Fortran, which makes data analysing easy.