Image-Based Visual Tracking Attitude Control Research on Small Video Satellites for Space Targets

Small video satellites are capable of conducting real-time continuous observation of space targets through attitude control and have broad application prospects. Since the traditional method of tracking based on location information needs the priori location information of the known target, effective tracking observation cannot be accomplished for non-cooperative targets. In this paper, we are going to design a visual tracking attitude control method for spatial targets based on image information, which can perform autonomous tracking observation for both cooperative and non-cooperative targets. Firstly, based on the principle of perspective projection, the internal and external parameter model of the camera is derived, and the conversion relationship between the inertial coordinate system and the pixel coordinate system of the on-board camera is established. Then the attitude dynamical model and kinematical model of the rigid satellite are given. The desired attitude and desired angular velocity of the small video satellite are derived based on the deviation information of the location coordinates of the target in the image plane projection point from the desired coordinates. Using the attitude error and angular velocity error as the control feedback quantity, the space target tracking PD controller is designed. The global stability of the closed-loop control system is proved using Barbalat theorem. The simulation results show that the proposed control method is effective for the visual tracking attitude control of space targets.