Research On Optimal Control Of Spacecraft Attitude Motion Planning

Under great promotion of scientific technology,the Spacecraft attitude control has obtained a quite good advancement.Meanwhile,the attitude control of Underactuated Spacecraft has developed a lot.In this dissertation,the writer studies the optimal control of Spacecraft and Underactuated Spacecraft attitude motion with Chebyshev-Gauss(CG)Pseudospectral Method.The main content is as follows:Firstly,two types of kinetic function are formulated based on Euler Angles and quaternions,respectively.The angular momentum of Spacecraft body,Thrusters,Momentum Wheels and Single-Gimbal Control Moment Gyros are deduced.And then,the general form of Spacecraft attitude dynamics equation including Thrusters,Momentum Wheels and Single-Gimbal Control Moment Gyros is systematically deduced according to the theory of angular momentum.Then,the form of one actuator and corresponding form of underactuation are also presented.Secondly,the Bolza form of Optimal Control Problem is used.The methods of solving the Optimal Control Problem are introduced.Taking account of the limitation of energy consumption about the partical issues,Time-Energy optimal indicator function is devised based on time optimal indicator function and energy optimal indicator function.The relevant theories and solution steps of Gauss Pseudospectral Method and CG Pseudospectral Method are introduced.Lastly,the energy optimal attitude maneuver problem for a Spacecraft with three Momentum Wheels is studied,and the accuracy of the result is verified based on time optimal indicator function.The energy optimal attitude motion plans for Underactuated Spacecraft with Momentum Wheels and Underactuated Spacecraft with Thrusters are made and compared with Gauss Pseudospectral Method,respectively.The optimal control of Underactuated Spacecraft with Momentum Wheels is studied by using time optimal indicator function and Time-Energy optimal indicator function,and then two results are compared.The optimal control problem without singularity for a spacecraft with redundant Single-Gimbal Control Moment Gyros is solved with energy optimal indicator function.