航天员舱外相对航天器运动轨迹摄动研究

用轨道根数描述载人航天器运动,在其轨道坐标系(LVLH)中,建立了含地球J2项引力和大气阻力摄动加速度的航天员质心相对航天器的运动模型。在参考轨道存在小偏心率时,对基于圆参考轨道假设推导的航天器编队飞行的线性时变系统状态矩阵进行了修正。仿真结果表明:对偏心率为0.002的航天器轨道,修正后模型所得航天员相对轨迹摄动量在离舱300 s后达到0.8%,是修正前模型的5倍,但计算量增加不超过5%,更适于航天员舱外飞行和近距离编队飞行建模。

Research on Astronaut Extravehicular Motion Perturbation Relative to Spacecraft

The astronaut＇s mass center motion relative to the spacecraft model in which the earth J_2 zonal harmonic and atmosphere drag perturbation acceleration were included was built in the local-vertical-local-horizontal coordinate system in this paper,when the manned spacecraft motion was described by the orbital elements.A modification was added to the procedure in computing the time varying linear system matrix of the astronaut＇s mass center motion while the slightly eccentric of the spacecraft orbit was in consideration.The simulation results showed that the astronaut＇s relative trajectory perturbation was about 0.8% for the spacecraft orbit with an eccentric（0.002,） which was 4 times larger than the unmodified model,but with no more than 5% computational work increment.The model was much suitable to the astronaut＇s extravehicular free motion and the modeling for the near-distance formflying.