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在无旋圆地球假设下,利用飞行器最大纵程、最小纵程和最大横程三个典型性能指标,建立了飞行器纵程和横程之间近似椭圆分布的解析关系式,通过该关系式能够快速得到纵程和横程对应的边界曲线,并根据球面三角形将纵程和横程的对应关系转化为经纬度关系,从而得到飞行器地球表面可达区域的边界线。通过与Legendre伪谱法计算所得最优解的比较发现,在不同经纬度,以不同航向角再入后,最优化方法计算得到的边界点与解析方法计算的边界曲线分布基本一致,并仿真分析了不同弧段再入后飞行器地面可达区域的变化特点,针对顺行轨道和逆行轨道完成了再入飞行器地面覆盖范围的计算。该解析方法通过3个典型指标就能够快速计算飞行器再入可达区域,有助于飞行器着陆场快速选择和初期轨道快速设计。
Under the assumption of the non-circular globe, the analytic relation of the approximate elliptic distribution between the longitudinal and the transverse of the aircraft is established by using the three typical performance indexes: the maximum longitudinal length, the minimum longitudinal length and the maximum horizontal distance of the aircraft. Through this formula, The corresponding boundary curves between longitudinal and transverse directions are obtained quickly and the correspondence between longitudinal and transverse directions is transformed into the latitude and longitude relationship according to the spherical triangle so as to obtain the boundary line of the accessible area on the Earth’s surface of the aircraft. Comparing with the optimal solution obtained by Legendre pseudospectral method, it is found that the distribution of the boundary curve calculated by the optimization method and the analytical method are basically the same at different latitudes and longitudes after reentry at different heading angles, and the simulation results are analyzed After reentry of different arcs, the change characteristics of the ground accessible area of the aircraft are re-entered, and the calculation of the ground coverage of the reentry vehicle is completed for the straight orbit and the retrograde orbit. The analytical method can quickly calculate the reentry area of the aircraft through three typical indicators, which can be used to quickly select the landing field of the aircraft and rapidly design the initial orbit.