非线性时变相似性理论下的空间拦截仿真研究

Research for Space Interception Simulation under Nonlinear Time-Varied Similarity

针对空间飞行器高速拦截过程地面物理仿真中,采用定常相似性理论难以在有限空间内实现高精度物理仿真的问题,提出了一种非线性时变相似性映射(NTVS)体系解决了大时空缩比系数与运动高精度模拟的矛盾。首先基于相似性量纲法推导了高速拦截过程的相似性准则,并分析线性定常相似映射(LCS)的不足。然后引入参考运动建立了一种时空缩比系数随时间自适应变化的相似性体系,并证明了该方法能够保证相似一致性。最后其通过运动的线性分离与独立映射方式解决了纵向高速接近运动与侧向小机动在同一物理平台上的仿真难题。仿真结果表明该方法相比于LCS能以较高精度完整再现高速拦截运动。

A nonlinear time-varied similarity(NTVS)simulation algorithm is proposed to solve the problem that the process of space interception is intractable to simulate with high precision in limited platform under the linear constant similarity(LCS).Firstly,the similarity criterions based on the dimensional analysis are given in the simulation of the interception motion at high-speed,and the disadvantage of LCS is analyzed.Then,the reference motion is introduced to establish a time-varied spatio-temporal transform system which scale factors are self-adaptive with time,and the method is proved to satisfy the similarity consistency.Finally the way that linear separation and independent mapping solve the problem that the large magnitude uniform motion in approaching directions and small magnitude overload motion in lateral directions are simulated in a limited ground platform.The results show that the NTVS can simulate the whole process of interception and perform better in accuracy comparing with that via LCS.