初值不确定轨道可达区域计算

为计算航天器轨道初值不确定造成的可达区域（RD），提出一种适用于椭圆参考轨道的计算方法。以航天器的名义轨道作为基线，定义一个随时间变化的移动参考平面，在此移动平面上建立名义轨道到可达区域上任一点的距离函数，函数的极大值点即为可达区包络的边界点，从而将问题转换为非线性方程组的求解问题，并对动力学模型部分线性化带来的误差进行了分析。随后采用变参数的自适应同伦算法对方程组进行求解。最后对航天器释放微小卫星的实例进行数值仿真，结果显示该方法可行有效。

Determination of Orbit Reachable Domain due to Initial Uncertainties

A general method is developed to find the 3D envelope of the reachable domain(RD), which is caused by the initial orbit uncertainties, for ellipse reference orbits. A reference plane changed with the time is defined and the nominal orbit is regarded as a baseline. Then the function of the distance from the baseline to RD envelope is established in the reference plane along the nominal trajectory. So the RD envelope boundaries problem turns into an issue of solving nonlinear equations. Subsequently the error caused by using the linear dynamic model partially is evaluated. A variable parameter self-adaptation homotopy algorithm is developed to solve the nonlinear equations obtained. The simulation results of a satellite released example show that the method proposed is feasible and effective.