GTO发射轨道的两级分解全局优化设计策略

文章提出了包含两级规划、轨道分解优化以及混合遗传算法的GTO发射轨道优化设计策略。针对最优控制变量和总体变量耦合所带来的收敛性差问题，建立了两级规划模型，其中上面级问题处理总体变量，下面级问题处理单独的轨迹控制变量。整个发射轨道优化设计问题被划分成两个轨道段优化设计子问题，采用串行混合遗传算法完成子问题的求解。选择一个二级GTO运载火箭，进行最大运载能力优化设计，对俯仰角选择、发射轨道参数选择等问题进行了分析，得出了一些有益的结论。算例分析结果表明所提出的GTO发射轨道优化设计策略的优良性能，在运载火箭总体设计中有良好的应用价值。

Bilevel Decomposition Based Global Optimization Approach for Launch Trajectories of GTO Launchers

An approach for GTO launch trajectory optimization design is proposed, which is consisted of bilevel programming method,trajectory decomposition optimization design and hybrid Genetic Algorithm. In order to overcome the poor convergence problems caused by the couple of system variables and optimal control variables, the bilevel programming model is set up, in which the master problem only deals with the system variables, and the junior problem only deals with the trajectory optimal control variables. The all-up launch trajectory optimization design problem is divided into two segment trajectory optimization design problems. The pipeline hybrid Genetic Algorithm is applied to solve the junior problem. As an example, maximal payload optimization design of a two-stage GTO launcher is completed, several problems such as how to choose pitch angle and how to choose parameters of launch trajectory are discussed, and several constructive conclusions are gained. This approach for GTO launch trajectory optimization has been testified with predominant performance index, and has great engineering value in launch vehicle system design.