结合遗传算法和优化Q-law算法的小推力轨道转移

提出了一种将遗传算法和优化的Q-law算法相结合的新轨道转移算法.为了合理利用能源,文中引入相对推进效率作为是否施加推力的门限.遗传算法用于搜索最短时间的优化轨道转移路径,将轨迹优化问题转化成有约束的参数优化问题,从而避免了两点边值求解难题.在轨道转移末端,为了提高目标转移精度并避免高频振荡,文中采用了结合模糊逻辑的优化Q-law算法.针对某一卫星轨道转移进行了数字仿真.结果表明,本文算法能够在实现最优时间轨道转移的同时,兼顾能源的消耗,并提高轨道转移精度.

LOW-THRUST ORBIT TRANSFER BY COMBINING GENETIC ALGORITHM WITH REFINED Q-LAW METHOD

A new orbit transfer method is presented by combining the genetic algorithm (GA) with the refined Q-law method. Considering the energy consumption, the relative thrust efficiency is introduced as a threshold deciding whether to thrust or coast. GA is used to achieve the global time-optimal orbit transfer. The trajectory optimization problem is transformed into the constraint parameter optimization problem, thus the nonlinear two-point boundary value problem is avoided. The refined Q-law method integrated with the fuzzy logic control is adopted for the end course, the vibration is avoided and the high precision is achieved. The numerical simulation of satellite orbit transfer is implemented. Results show that the new method can achieve the time-optimal orbit transfer and the low energy consumption, thus improving the transfer precision.