基于模糊多目标的高超声速飞行器再入轨迹设计

Reentry trajectory design based on fuzzy multi-objective optimization of hypersonic vehicles

针对多约束条件下的高超声速飞行器再入轨迹的优化问题,考虑多个具有不同重要性等级的优化指标,提出基于模糊多目标的轨迹设计方法.首先,利用直接配点法,将最优控制问题转化为带优先级的非线性多目标规划问题;然后,基于模糊满意优化的思想,根据更重要目标具有更高满意度的原则,将优先级表示为满意度序,并设计两步式优化模型.通过调节参数,能获得同时满足优化和重要性等级要求的最优轨迹.仿真结果表明了所提出方法的有效性.

Considering multiple performance indices with different importance levels,a trajectory design method based on fuzzy multi-objective optimization is proposed for reentry trajectory optimization of hypersonic vehicles with multiconstraints.Firstly,the optimal control problem is transformed into the nonlinear multi-objective programming problem with preemptive priorities by using the direct collocation method.Then,based on fuzzy satisfactory optimization and the principle that the more important objective has higher satisfactory degree,preemptive priorities are modeled into an order of satisfactory degrees.The two-step optimization models are designed.By adjusting the parameter,the optimal reentry trajectory satisfying the requirements of optimization and importance of the performance indices can be generated.Finally,the simulation result shows the effectiveness of the proposed method.