摘要
针对扰动引力大小和方向随空间位置变化的特点,将自由段弹道按射程进行分段,动态建立北天东坐标系并计算高阶扰动引力加速度,将其天向分量等价为均质圆球质量偏差,并修正标准椭圆轨道方程;将扰动引力对北向和东向的影响近似为匀加速直线运动,推导出运动微分方程的解并在地心坐标系内对弹道飞行器的位置和绝对速度进行更新计算,从而提出了高阶扰动引力对自由段弹道影响的近似解析解计算方法。数值计算结果表明,该方法具有较高的计算精度,可用于弹道飞行器高精度实时制导和轨道预测等方面。
Considering the variety of the disturbing gravity with the dimensional position of the ballistic vehicle,this research divides the free flight trajectory into several stages by the flight range. Furthermore,the dynamic North-Air-East coordinate system was established and the high-order disturbing gravity was calculated. Next,the equation of normal elliptical orbit was modified by mass deviation of the Earth which caused by the upward disturbing gravity acceleration,the influence of the north and east disturbing gravity were considered as rectilinear motion with constant acceleration. Then,the solutions of the differential equations of motion were deduced,and the parameters of the position and velocity were updated in the geocentric coordinate system. Finally,the simulation results show that the analytical solution has a higher computational accuracy,and has an important application prospect in the precision real-time guidance and orbit forecast.
出处
《飞行力学》
CSCD
北大核心
2018年第1期56-60,共5页
Flight Dynamics
关键词
扰动引力
自由段弹道
解析解
disturbing gravity
free flight trajectory
analytical solution
