基于H∞ 控制的非线性末制导律设计

 针对三维目标拦截问题，提出一种新的具有强鲁棒性的非线性H_∞末制导律。基于三维弹目相对运动学的非线性关系，将目标机动作为系统扰动，建立了弹目相对运动的数学模型。同时,基于零化弹目视线角速率的思想，提出一种全局非线性H_∞稳定控制策略，得到了连续的非线性末制导律。该方法利用Lyapunov稳定性理论严格证明了制导系统的全局渐近稳定性，并且无需求解哈密尔顿-雅可比-艾萨克斯（HJI）偏微分方程，同时也无需控制弹目相对运动速度。数字仿真表明，和比例导引律相比，这种制导律对高速大机动目标具有很强的鲁棒性和适应性，并能获得良好的制导精度。

Design of H_∞ Control Based Nonlinear Terminal Guidance Law

For the case of three-dimensional interception, a new continuous nonlinear H_∞ guidance law with robustness is proposed. The mathematic model is built according to the three-dimensional relationship between the missile and the target whose acceleration is introduced as disturbance. Based on the method of zeroing the rate of the line-of-sight angle, a global nonlinear H_∞ control strategy is contrived to obtain the continuous nonlinear guidance law. The asymptotic stability of the guidance system is strictly proven by Lyapunov stability theory. Applying the method, it is unnecessary to solve the Hamilton-Jacobi-lsaacs (HJI) partial differential equation and control the relative velocity of the missile and the target. Finally an illustrative example is given to show that the new guidance law is more robust and suitable than the proportional navigation law for the missile to intercept a target with high velocity and high maneuverability, and that it is capable of achieving better precision of guidance.