In this paper difference equation of motion fr om one point to another point on the earth is derived from the geodesic equation on the earth and spherical trigonometry formulas. Some difference track formul as of a maneuvering object are also given.

• 以大地椭球三角形模型为基础 ,利用地球表面二点间最短路径的大地线方程和球面三角形的有关公式 ,建立了由地球表面一点运动到另一点的差分运动方程 ,同时也给出了在进行航向机动时的差分运动轨迹。