The Research On The Control Algorithms Of Large-angle Maneuver Of Small Wheel-controlled Satellite

As the mission requirement of a satellite is changing rapidly, new demand has been put forward for the satellite design that the development cycle must be as short as possible. The usage of small satellite is becoming more and more popular due to its short development cycle. This thesis focuses on the research of the control algorithms of large angle maneuver of small rigid satellite.Firstly, the dynamic and kinematic model of a rigid small satellite is set up using quaternion as the parameters to describe the satellite’s attitude. Then, the quaternion feedback control algorithms are analyzed systematically. To begin with, the classical PD feedback control logic is analyzed based on the Lyapunov stability theorem. Then the two-level satiation controller is introduced considering the constrains on the control torque and maximum angular momentum of the flywheel as the actuator. Because the model of a satellite has a cascaded structure, so the back-stepping feedback controller is designed. For all the control algorithms mentioned above, we have simulation results analyzed in comparison.As to the optimal control problem of the satellite maneuver, these are few articles considering the influence of the dynamics of the actuator. In this thesis, the Minimum Principle is firstly adopted to analyze the problem of time optimal attitude maneuver of a small satellite with the dynamics of its actuator, i.e., flywheels. Then the problem is solved numerically using the Legendre Pseudo-spectral Method. The open-loop time optimal control trajectory is achieved. As to analyze the influence of the dynamics of flywheels on the control performance of the optimal controller, the same optimal problem without the dynamics of flywheels is analyzed with the same method. Considering that there exits disturbance torque on orbit, the feedback controller is designed to track the time-optimal control trajectory and suppress the influence of the disturbance torque. Finally the simulation results are analyzed in comparison.