基于NFTET的高超声速飞行器鲁棒轨迹重构设计

Design of Robust Trajectory Reshaping for Hypersonic Vehicle Based on NFTET

考虑高超声速飞行器故障下安全再入飞行问题,针对飞行器发生较大故障的情况,提出了基于相邻可行轨迹存在定理(Neighboring feasible trajectory existence theorem,NFTET)的鲁棒在线轨迹重构算法。在标称情况下基于反馈线性化预测校正制导算法生成满足各种约束条件的再入轨迹;由于NFTET只适用于发生较小故障的情况,为保证较大故障下飞行器仍能以较高精度安全着陆,基于NFTET理论设计了鲁棒轨迹重构算法,得到了较高落点精度的飞行轨迹。仿真结果表明,本文所提出算法能有效解决飞行器较大故障下的安全再入轨迹重构问题,提高了飞行器的自主容错能力。

For the safety reentry flight problem of hypersonic vehicle at fault,a robust trajectory reshaping algorithm is proposed based on the neighboring feasible trajectory existence theorem( NFTET) under the large failure of the vehicle. In the nominal case,an improved predictor-corrector guidance law based on the feedback linearization theory is proposed to generate the reentry trajectory for satisfying the various constraints. Since NFTET is only applied to the occurrence of small failures,to ensure the safe landing with high precision under the large failure,the robust trajectory reshaping algorithm is designed based on NFTET,and the higher landing accuracy of the flight path is obtained. The simulation results show that the algorithm proposed in this paper can effectively solve the problem of the safety reentry trajectory reshaping under the large failure of vehicle,and improve the autonomous fault tolerance ability of the vehicle.