针对火星着陆任务高实时性和低燃耗的需求,提出了一种新的基于开环燃料最优解的精确着陆制导策略。通过分析开环燃料最优解特性,设计了利用发动机推力幅值切换处的状态作为路径点结合最优线性制导律进行分段制导的制导策略,在无需存储全部燃料最优轨迹的前提下,实现具有近燃料最优特性的着陆任务,节省了大量的存储空间。同时详细讨论了包括全局燃料最优解获取、路径点提取、路径点拟合等一系列关键问题,并通过典型火星着陆场景的大量数学仿真验证了所提出策略的可行性和优越性。
In order to satisfy real time and low fuel consumption requirements of Mars descent phrase,a new Mars precision landing guidance strategy was proposed based on fuel optimal solutions.Based on the characteristic analysis of the open loop fuel optimal solutions,states corresponding to thruster force magnitude switching time are directly selected as intermediate waypoints,and then a linear guidance algorithm was implemented in each segments to achieve fuel optimal performance.Several key problems,including the computation of global fuel optimal solution,waypoint selection,waypoint fitting,and derivation of linear guidance algorithm,were discussed in details,and the feasibility and superiority of the proposed strategy have been evaluated through a variety of typical Mars landing scenarios.