连续常值推力机动分析与应用

Analyses and Applications of Continuous Constant Thrust Maneuver

连续常值推力机动是空间飞行常用的轨道机动方式。其中,小推力适合于地球轨道航天器交会机动,而切向或周向推力以及较大的正径向推力可用于脱离地球引力场的逃逸飞行,执行星际交会使命。应用常推力作用下的质心运动方程,对机动推力的量值没有限制;在航天器交会应用中,对相对距离也无要求。这种方法可直接获得向径、轨道速度等参数随时间或极角(绕地心的转动角)的变化,便于分析轨道转移与逃逸运动,有助于飞行使命与运动轨迹的设计。特别是,若机动转移的初轨为圆轨道,在推力较小、飞行时间不长的情况下,应用量纲1形式的运动方程,可获得具有工程应用价值的近似解。

Continuous constant thrust is very important in orbital maneuver and escape flight. Small thrust maneuvers are fit for spacecraft rendezvous, and the tangential （or transverse） thrust and radial high-thrust can be applied in escaping from the earth＇s gravitational field. By using the motion equations of constant thrust maneuver, there is no limit on the thrust-level and no restraints on the relative distance when used in spacecraft rendezvous. Radius and orbital velocities can be directly expressed as functions of time or polar angle, which is helpful for designing flight mission and motion trajectory. Especially, when the initial orbit is circular, for small thrust and short flight time, approximate analytic solutions can be derived from non-dimension form of the motion equations.