再入飞行器的标称攻角在弹道规划以及飞行器覆盖能力分析中起到重要作用,由于再入飞行中气动加热严重,过载和动压约束严格,给标称攻角的设计带来很大困难.针对弹道射面内最大纵程和最小总热载荷问题,在考虑热流、动压和过载约束下分别进行标称飞行攻角的优化设计.首先将过程约束转化为对控制量攻角的约束,将需要优化的标称攻角通过分段线性函数参数化,把最优控制问题转化为4个参数的寻优问题,然后利用遗传算法获得参数的初始猜想,并设计序列二次规划(SQP,Sequential Quadratic Programming)算法求解.仿真结果显示该方法能够快速获取再入标称飞行攻角,为再入轨迹优化和制导总体设计提供参考.
The design of nominal attack of angle is important for re-entry vehicle. It is also a challenge because of constrains such as air heating, loading and dynamic pressure. A rapid optimal design method for nominal attack of angle was proposed. First the path constrains were converted into control constrain for attack of angle. Then the attack of angle was parameterized by four parameters. The genetic algorithm was used to obtain the initial guess of parameters. Finally the re-entry trajectory was solved by sequential quadratic pro- gramming(SQP) technique. The simulation results show that the method finds the optimal nominal attack of angle quickly and can be used for the re-entry trajectory optimization and guidance researches.