RLV末端能量管理段三维制导轨迹推演研究

Research on 3-D guidance trajectory propagation of terminal area energy management for RLVs

研究了重复使用运载器(reusable launch vehicle,RLV)末端能量管理段(terminal area energy manage-ment,TAEM)三维制导轨迹推演算法。根据初始点和终点的位置、航向、动压,规划动压参考剖面和横侧向参考轨迹,采用基于高度的质点动力学方程推演生成符合过载、动压、终点位置和航向约束条件的三维制导轨迹。横侧向参考轨迹的设计可以分成两步:第一步,消除横向的位置误差,同时减小纵向的位置误差;第二步,消除纵向的位置误差。根据纵向位置误差大小,组合使用三种模态的轨迹予以消除,节省了计算量。仿真计算显示,三维制导轨迹推演算法具有快速、准确、对初始点位置和航向分布鲁棒性强的特点,为在线轨迹设计提供了基础算法。

A 3-D guidance trajectory algorithm of terminal area energy management（TAEM） for reusable launch vehicles（RLVs） is researched.According to initial and autolanding interface（ALI） dynamic pressure,a reference dynamic pressure profile is planned.Lateral reference trajectory planning includes two steps,that is,erasing the lateral position error and longitudinal position error.During erasing lateral position,the longitudinal error is being reduced.According to the size of the longitudinal position error,three modes of trajectories are used to erase it by a set of logical procedures.Based on the reference dynamic pressure profile and lateral reference trajectory,a 3-D guidance trajectory is propagated by means of the longitudinal-lateral coupling equations of motion.Simulation computations show that the trajectory algorithm can propagate a 3-D guidance trajectory fast,exactly and robustly.Therefore,it can be a candidate for onboard trajectory generation.