地球静止轨道-低轨道最优异面转移方法

研究了轨道转移飞行器（orbital transfer vehicle, OTV）从地球静止轨道向低轨道的最优异面转移过程，提出了解析法和智能优化算法。在解析法中，完整地推导了最优转移轨道的求解方法，提出了最优转移轨道应满足的条件，并采用牛顿迭代法求解第1次速度脉冲应改变的轨道倾角。以离轨点位置、入轨点位置和转移时间为优化变量，采用遗传算法对最优转移过程进行求解，给出了遗传算法求解该优化问题的设计步骤，并将变轨过程在卫星工具包（satellite tool kit, STK）场景中进行了演示。仿真结果表明两种方法均能满足Lawden一阶最优必要条件。

Optimal noncoplanar orbital transfer between GEO and low-earth orbit

The optimal noncoplanar orbital transfer between geostationary earth orbit(GEO) and low-earth orbit for the orbital transfer vehicle(OTV) is studied,and analytical method and intelligence optimization algorithm are proposed.For the analytical method,the solution of the optimal transfer orbit is fully derived.The conditions which the optimal transfer orbit should be satisfied are given,and the optimal changed inclination due to the first impulse is solved by Newton iteration.The genetic algorithm(GA) is used to solve the optimal transfer orbit,where the optimal solution is composed of deorbit position,reorbit position and transfer time.The steps for GA are given and the demo of orbital transfer is carried out in Satellite Tool Kit(STK).The simulation results show that the Lawden’s first-order optimality condition can be satisfied for both methods.