降低亚轨道飞行器再入法向过载峰值的攻角设计方法

Research on Attack Angle Design Method for Sub-Orbital Vehicle Re-Entry to Reduce the Normal Acceleration Peak Value

针对亚轨道飞行器再入中的大过载问题,提出一种通过保持法向过载动态平衡以大幅降低法向过载峰值的攻角设计方法。该方法基于再入飞行中过载演化特性,通过自主分段、预测反馈及迭代修正对再入攻角进行设计,使攻角变化率与法向过载的期望平衡值相适应,并可经过重复计算及收敛实现法向过载峰值最小化。仿真计算的结果表明,该方法能够大幅降低亚轨道飞行器再入中的法向过载,且按照该方法设计所获攻角策略可有效用于亚轨道飞行器再入任务规划、再入轨迹和制导律设计。

An attack angle design method for solveing large overload problem for sub-orbital vehicle re-entry is proposed in this paper. Based on the normal acceleration dynamic equilibrium, this method is designed to reduce the normal acceleration peak value. In order to accommodate the angular rate of attack angle to the desired equilibrium value of normal acceleration, characteristics of the overload are analyzed first. Autonomous segmentations, feedback forecasting and iterative correction are used to design re-entry attack angle with an aim to minimize the normal overload peak. Numerical results demonstrate that the proposed method can reduce the vertical overload peak value effectively. It is found that the attack-angle strategy designed by the method can be used for sub-orbital spacecraft re-entry mission planning, re-entry trajectory and guidance law design.