日地系L2点与日火系L1点转移轨道设计

将太阳-地球-火星-飞行器组成的四体问题分解成由太阳-地球-飞行器和太阳-火星-飞行器两个共面圆形限制性三体问题,设计日地系L2点与日火系L1点Lyapunov轨道之间的转移轨道,该转移轨道可以作为探测火星时的低能中间转移轨道.采用Richardson三阶近似解作为初始值,运用微分修正方法分别得到两个不同三体系统下拉格朗日点的精确Lyapunov轨道.基于Lyapunov轨道不变流形以及微分修正方法,设计了日地系L2点与日火系L1点间的转移轨道.将所得结果与基于Halo轨道不变流形设计的转移轨道进行了对比.结论表明:利用Lyapunov轨道不变形设计探火中间转移轨道相较于利用Halo轨道不变流形设计探火中间转移轨道在能量消耗以及飞行时间上都存在优势.

Transfer trajectory design between L2 in Sun-Earth system and L1 in Sun-Mars system

The transfer trajectory bwtween L2 in the sun-earth system and L1 in the sun-mars system design using invariant manifold of the restricted three body problem is studied. Considering mars,earth and sun in the same plane, the four body problem of sun-mars-earth-spacecraft was divided into two three body problems, that were the three body problems of sun-earth-spacecraft and sun-mars-spacecraft. A Lyapunov orbit of Lagrange liberation point was designed with different correction method and Richardson three-order approximation solution as initial conditions. The transfer trajectory between Lyapunov orbit's invariant manifold of the two different restricted three body problems was designed with different correction method and the results was compared with the transfer trajectory between Halo orbit's invariant manifold of the two different restricted three body problems.The simulation shows that transfer trajectory design using the invariant manifold of Lyapunov orbit cost lower energy and shorter time of flight.