三角平动点在深空探测中的应用前景

Applications of the Triangular Libration Points in Deep Space Explorations

与共线平动点不同,圆型限制性三体问题中的两个三角平动点在一定条件下,无论是线性意义下还是非线性意义下,都是稳定的,其附近存在着周期与拟周期轨道,在深空探测中有应用前景.该文首先简单介绍三角平动点附近运动的动力学特征,然后以日-(地+月)系和地-月系两个三体系统为例,进一步阐述真实引力模型下三角平动点附近的运动状态,最后以这两个三体系统为例,探讨了三角平动点探测器的发射和定点轨道控制问题.

Different from the collinear libration points, the triangular libration points in the Circular Restricted Three-Body Problem （CRTBP） are stable when the mass ratio of the system satisfies some conditions. Since they have constant configurations with respect to the two primaries, these points may be useful for future deep space explorations. Generally, there are periodic and quasi-periodic orbits around these points. These orbits are stable and can be used as nominal orbits for spacecrafts. However, in the real gravitation model of the solar system, these points may become unstable or at least the orbits around them will deviate inevitably. So orbit control is necessary. Due to their better stability than the collinear libration points, orbit control around them may need less energy. In this paper, the dynamics of these points were firstly stated. In the cases of the sunearth＋moon system and the earth-moon system, two real gravitation models of the solar system, the motion around these points was further investigated. Finally, problems concerning the transfer of a spacecraft to these points and orbit control of the spacecraft were discussed.