Optical Tracking System Of Rigid Body Attitude Control

Many achievements have been obtained in the field of attitude control of a rigid body in recent years, and also have been applied to areas such as spacecraft, robotics, vehicles systems. The paper describes attitude of a rigid body utilizing quaternion parameter and solves the attitude control problem of a optic-electronic observatory tracking system. First, a attitude tracking control problem is presented within a general framework of a optic-electronic observatory tracking system. Unit quaternion is introduced to avoid the singularity of rigid body抯 kinematics. A global and error quaternion梑ased rate/attitude tracking controller is derived by Lyapunov second method on base of kinematics and dynamics, and makes the system achieve global tracking. Zero梥tate steady, actuator saturation, parameter unknown and robust control of the attitude motions are also particularly described. Second, general trajectories of straight line, circle and helix motions of the aircraft are achieved for optic-electronic observatory sensor to fulfill certain fight missions. The tracking performance of the system is improved for the tracking order of the sensor platform is not sin, step or slope input as before. General controller is designed utilizing proportion and integral of errors along the scheduled trajectories. Finally, attitude control theory is applied to optic-electronic observatory, with general trajectories of straight line, circle and helix motions. It proves that the resulting closed條oop system ensures global and large angle tracking using error quaternion梑ased rate/attitude controller. Tracking instruction of the sensor platform and the actuator saturation are also efficiently settled. The simulations suggest the controller has favorable tracking stability and robust performance, and has great potential in optic梕lectronic observatory platforms and many other applications.