Trajectory tracking for RLV terminal area energy management phase based on LQR

Abstract

A new longitudinal trajectory tracking law for the Terminal Area Energy Management (TAEM) phase of the Reusable Launch Vehicle (RLV) is presented in this paper. The conventional PID method controls the height and the velocity by the angle of attack and the angle of airbrake respectively, and no coupling is considered. To improve the tracking precision, the new tracking law is designed based on the linear quadratic regulator (LQR) theory where the coupling is taken into account. Finally, the trajectory tracking law based on the LQR is simulated and compared with the conventional method. Simulation results indicate the effectiveness and the robustness of the new tracking law.

CACLA-Based Trajectory Tracking Guidance for RLV in Terminal Area Energy Management Phase

“…The online learning procedure of guidance strategy is the same as the offline training. The weight vectors of critic are updated by ( 20)- (23). The weight vectors of actor are updated by ( 27) and ( 28), but only when the TD error is positive.…”

“…In the research of guidance algorithms, the mature guidance method is to use a small perturbation approximation method or feedback linearization theory to obtain the linear model of RLV. Then, the guidance law is designed based on robust control theory or Linear Quadratic Regulator (LQR) to track the reference trajectory [ 21 , 22 , 23 ]. The performance of these methods has a tight relationship with the accuracy of RLV modeling.…”