A Real-Time Trajectory Planning and Guidance Algorithm for Terminal Area Energy Management

Abstract

AbstractThe task of terminal area energy management (TAEM) is to plan a trajectory from the end of the reentry phase (approximately 30km) to the landing window (approximately 3km). To ensure the safety of the reusable launch vehicle (RLV), both path constraints and terminal constraints should be met. This paper proposes a novel real-time trajectory planning algorithm to deal with the TAEM task. Firstly, the longitudinal trajectory profile and the lateral trajectory profile are designed separately to satisfy the path constraints and the terminal constraints. Secondly, the trajectory parameters are modified online by newton iteration according to the terminal error, which makes the algorithm more robust. Thirdly, taking vehicle damage into consideration, the landing window is chosen by RLV’s range capability and the initial parameters of the trajectory are predicted by the neural network so that the algorithm can meet the real-time requirement. Simulations demonstrate the effectiveness of the proposed scheme.KeywordsTAEMRLVTrajectory planningGuidanceNeural network