The Attitude Control System Design And Simulation Of Microsatellite

The thesis is derived from the microsatellite project of school. The research work is to study the attitude control system of the microsatellite.Firstly, the research situation of attitude control system of microsatellite in the world is introduced and the attitude control system of several satellites which has been launched successfully and their configuration, functions and performance are outlined.This dissertation focus on the design and simulation of the attitude control system. The dynamics model is developed, and the key parameters of actuators of this system are determined preliminarily based on the dynamics model and the survey and analysis work. Then, the design of detumbling controller is studied, magnetic detumbling controller and gas detumbling controller are designed and analyzed respectively, the controller for initial attitude acquisition is also studied. The momentum wheel startup method is discussed in detail, and three methods for startup are presented, the feasibility, advantages and disadvantages of the three methods are testified by simulation.Lastly, the attitude stabilizing control system of microsatellite which mainly uses momentum wheel is studied. The relationship of motion during the three axis is analized, the pitch channel and roll-yaw channel are then analized respectively, the stabilizing controller is designed, and the problem of wheel unloading and protected mode for stabilization are also discussed and simulated.