Target spacecraft tracking control based on image information

The gain-switching PD control law for target tracking is proposed with the introduction of the image plane error, defined as the deviation between the target image centroid and the center of the image plane, into the close-loop of tracking control. The switching function is designed for switching of PD gain in order to compensate the effects of measurement error, thruster deviation, inertia uncertainty and disturbing moment, thus improving the system stability and anti-jamming performance. Using the visual characteristics error in the image plane directly avoids calibration of camera intrinsic parameters and solution for target attitude, which simplify the servicing spacecraft configuration. The method for estimation of control parameters is put forward and the stability is analyzed based on Lyapunov theory. Numerical simulations indicate that the system works well for tracking the complex maneuvering target while considering typical uncertainty factors. The results demonstrate the effectiveness of visual tracking control strategy and robustness to multiple types of uncertainty.