中文摘要：

对已有的三维球坐标系导弹-目标相对运动模型进行适当变换，得到非奇异的导弹-目标相对运动的三维非线性模型，并对所得模型设计满足输入-状态稳定（ISS）的非线性鲁棒导引律．该导引律在跟踪机动目标的情况下，控制导弹-目标间相对距离，使其按指数渐近趋于零．仿真结果表明，所设计的导弹导引律实现了打击机动目标的目的，并且在鲁棒性方面具有优势，可为实际工程应用提供新的参考．

英文摘要：

A three-dimensional missile-target relative motion model was established in spherical coordinate, and some proper transformations were presented. The new model exhibits nonsingularity property so that it is convenient to design guidance laws for the system. It was used to derive nonlinear ISS robust guidance laws while satisfying the Lyapunov stability. It considers the relative distance between the missile and target as the output of the control system, and the presented guidance law drives the output to zero exponentially when the motion of the target is unknown. Simulation results indicate that the guidance laws exhibit strong robustness properties against disturbances from the target＇s maneuvers, so it is more convenient for comprehension and practical applications.