高超声速滑翔飞行器在线轨迹优化与再入制导方法研究

A reentry guidance method with online trajectory optimization for hypersonic glide vehicle

基于伪谱轨迹优化方法和线性二次型调节器轨迹跟踪方法,提出了一种在线更新标称轨迹的高超声速滑翔飞行器制导算法。对每个制导周期开始时刻的飞行器实际状态量和标称状态量的差值进行计算,当实际轨迹距离标称轨迹的偏差过大时,则以飞行器当前实际状态量为初始状态对剩余飞行轨迹进行在线优化,作为下一制导周期轨迹跟踪的标称轨迹;并在考虑初始状态误差、升阻力系数误差及风扰动的情况下进行仿真研究。仿真结果表明,在线更新标称轨迹的制导算法对于各种不确定扰动具有更好的适应能力,而且相对于离线轨迹优化制导具有更高的准确性和鲁棒性。

A guidance algorithm with online updating of the nominal trajectory is proposed for the reentry guidance of hypersonic glide vehicles based on pseudo-spectral trajectory optimization and trajectory tracking using the linear quadratic regulator(LQR)method.The difference between the actual and the nominal state of the vehicle at the beginning of each guidance cycle is calculated.When the actual trajectory deviates significantly from the nominal trajectory,the current state is used as the initial state for online optimization of the remaining flight trajectory.This optimized trajectory then serves as the nominal trajectory for tracking in the next guidance cycle.Numerical simulations are carried out considering the initial state error,lift and drag coefficient error and wind disturbance.The simulation results show that the guidance algorithm based on online update of nominal trajectory possesses a superior adaptability to various uncertainties,and offers better accuracy and robustness compared to the guidance based on offline trajectory optimization.