基于联立框架的轨迹优化算法

A Trajectory Optimization Algorithm Based on Simultaneous Strategies

为了更好解决复杂多约束下的在线轨迹优化问题,研究了一种基于联立求解框架进行轨迹优化的算法。此方法是一种直接法,先利用有限元正交配置法将状态和控制变量同时离散化,然后使用内点算法对离散得到的非线性命题进行求解。从平衡解的精度和计算代价的角度出发,引入了针对内点算法的收敛深度控制策略来改进方法的快速收敛性。最后,以某航天器月面上升段最优入轨任务为算例,验证了算法的精度和快速收敛性。

In order to fairly solve the complex online trajectory optimization problem with multiple con- straints, a trajectory optimization algorithm based on simultaneous strategies is involved in this paper. This algorithm can be divided into the direct method. Firstly, the state variables and control variables are discre- ted by using the method of orthogonal collocation on finite elements （OCFE）, then the solution of discreted nonlinear derivation is performed by using interior point optimizer （IPOPT）. In order to balance the solu- tion precision and computational cost, convergence depth control strategy is adopted to enhance the rapid convergence of the algorithm. Finally, the simulation is implemented under the scene of a certain manned spacecraft returning from lunar surface, the numerical results show the precision and rapid convergence of this algorithm.