高精度空间非合作式相对轨道状态预报

为了解决接近空间非合作目标过程中的相对导航问题,提出一种基于相对轨道动力学方程和二阶龙格库塔积分公式的高精度空间非合作目标相对轨道预报模型。考虑地球J2摄动加速度,将目标轨道方程在参考轨道附近展开,保留至引力加速度差的二阶展开项,并进一步推导考虑J2摄动的参考轨道角速度和角加速度,建立相对轨道动力学微分方程;在给定相对轨道初值的情况下,采用二阶龙格库塔积分公式进行相对轨道预报。该模型采用数值积分方法,对相对轨道动力学模型形式没有限制,通用性好,适用范围广;选择低阶龙格库塔公式积分预报,既减少了计算量又保证了计算精度。设置高轨和低轨两种相对运动仿真场景,仿真结果表明了模型的通用性和精确性。

High Accurate State Propagation of Non-Cooperate Relative Orbit in Space

In order to resolve the problem of relative navigation during the course approaching a non-cooperative space target, a highly accurate state propagation model of non-cooperative relative orbit motion was proposed on the basis of the relative orbit dynamics equations and the second order Runge-Kutta formula. Taking the J₂ perturbation into account and expanding the target orbit equations into second order Taylor series beside the reference orbit, the angular velocity and the angular acceleration of reference orbit were further deduced and the relative orbit dynamics differential equation was built. After giving the initial value, the second order Runge-Kutta method was used to propagate the relative orbit motion. With the use of numerical integral method, the model can be widely used without any limited condition in relative orbit dynamics model forms; with the use of second order Runge-Kutta method, the computing efficiency is improved while the calculation accuracy is guaranteed. Two simulation scenarios, a low Earth orbit scenario and a high Earth orbit scenario, were designed to testify the generality and precision.