基于拟平衡滑翔的数值预测再入轨迹规划算法

Numerical prediction method of reentry trajectory planning based on quasi equilibrium glide condition

摘要:

针对高超声速飞行器三维约束再入轨迹规划问题,提出一种基于拟平衡滑翔条件的数值预测再入轨迹规划方法．该方法在以倾侧角为控制量的基础上,增加对攻角的控制作用,能够充分利用再入飞行过程中的拟平衡滑翔条件．根据飞行路径角剖面和攻角剖面分别对再入航程和终端速度进行数值预测; 借助拟平衡滑翔条件计算能够保持平衡滑翔飞行的倾侧角,同时将飞行过程约束转化为对倾侧角的约束; 以CAV-H再入飞行器为例进行仿真分析．仿真结果表明,该数值预测轨迹规划算法不仅能够使CAV-H的再入轨迹具备平滑弹道的优良特性,而且对目标点的改变具有很强的适应性．

Abstract:

Based on the quasi equilibrium glide condition (QEGC), a numerical prediction method of three-dimensional reentry trajectory planning is presented for hypersonic vehicles with constraints. In this paper, both the angle of attack and the bank angle are seen as the control variables, so the QEGC can be fully used. Firstly, the range and the terminal velocity is predicted numerically according to the profiles of the angle of attack and the flight path angle respectively. Secondly, the bank angle is then calculated to keep the trajectory flying along with the QEGC, and the path constraints in flight are transformed into the bank angle constraints. Finally, the simulations for the CAV-H are constructed. The simulation results demonstrate that the proposed method can make the trajectory smooth enough, and has flexibility for different targets.