Shuguang Zhang

Trajectory oscillation suppression control for lifting reentry vehicles with predictor-corrector guidance

The equilibrium glide-based predictor-corrector reentry guidance algorithm has received increasing attention due to its good adaptiveness. However the big disturbance or insufficient accuracy of prediction could lead to large correcting bias, causing departure from equilibrium glide state and phugoid oscillation of reentry trajectory, which could induce large thermal and dynamic loads and are detrimental to the vehicle and the crew. In order to reduce the reentry risk to the vehicle and the crew, the reentry trajectory qualities should be improved, by designing an adaptive controller to damp the trajectory oscillation for the predictor-corrector reentry guidance system. Through analyzing the longitudinal reentry dynamics of lifting vehicles, the approximate analytical solution of the feedback gain is derived, and then an adaptive reentry trajectory oscillation suppression controller is developed. Finally, the effectiveness of the adaptive controller is well verified, by comparing the simulation results of the predictor-corrector reentry guidance algorithms with and without the reentry trajectory oscillation suppression controller.