提出一种基于正弦指数函数的小推力借力飞行转移轨道初始设计方法。建立极坐标形式的正弦指数函数表达式,用于模拟小推力转移轨道,并用绕圈参数和飞行路径角对转移轨道的参数进行表征;在约束条件下对转移轨道参数进行离散化处理,求解转移轨道与目标星投射轨道在参考面内的交点,计算到达目标轨道时刻的极角,进而得出小推力转移轨道的初始设计参数;设计了地球—木星的火星借力小推力转移轨道,仿真结果验证了该方法在小推力转移轨道初始设计中的快速性与准确性。
In this paper,an initial design method of low thrust transfer trajectories using gravity-assist based on exponential sinusoid function is introduced.Firstly,the exponential sinusoid function is established under polar coordinates to simulate the low thrust transfer trajectories.All the parameters of the transfer trajectories can be described by flight-path-angle and winding parameter.Secondly,the parameters of transfer trajectories are discretely processed with constraints,and then obtaining the intersection points of transfer trajectories with target's projected trajectories to get the polar angle to the target trajectory.The rest parameters based on exponential sinusoid can also be obtained,so that we can get the initial design parameters of low thrust transfer trajectory.Finally,the Earth-Jupiter low thrust transfer trajectory using gravity-assist by Mars is designed.The simulation results show that the method is able to search out the initial design parameters of low-thrust transfer trajectory quickly and accurately.