针对防空导弹拦截高速机动目标的难题,提出了一种考虑终端视线角约束的三维末制导律。基于三维弹目相对运动模型,建立了目标加速度自适应估计模型,该模型实现了对弹目视线角速度的有效跟踪,以及对目标加速度的高精度估计。进一步,建立了终端视线角约束从地面坐标系至弹体坐标系的转换关系,并结合滑模变结构控制与有限时间收敛理论,设计了一种能够直接应用导引头测量信息的末制导律,通过推导证明了制导系统状态量的稳定性和有限时间收敛性。数字仿真验证结果表明,该末制导律不仅能将视线角有效控制至期望值,还将平均脱靶量显著缩减至1米以内。相较于传统的偏置比例导引律,显著减小了防控导弹拦截高机动目标时末端需用过载,提升了导弹的制导精度。此外,该制导律直接利用导引头测量信息,有助于降低制导系统的复杂度,对防空导弹制导技术的研究具有重要的参考和应用价值。

To address the challenge of intercepting high-speed maneuvering targets with anti-aircraft missiles,a three-dimensional terminal guidance law that considers the constraints of the terminal line-of-sight angle is proposed.Initially,an adaptive estimation model for target acceleration is established,based on the three-dimensional relative motion model between the missile and its target.This model effectively tracks the line-of-sight angular velocity and achieves high-precision estimation of the target’s maneuver acceleration.Following this,the formula for converting the terminal line-of-sight angle constraints from the ground coordinate to the missile coordinate is derived.Subsequently,a terminal guidance law that is capable of directly utilizing the missile’s seeker measurement information is designed,by integrating sliding mode variable structure control with finite-time convergence theory.It is rigorously proven through mathematical derivations that the proposed guidance law ensures the stability and finite-time convergence of the guidance system’s state variables.Lastly,a digital simulation validation is conducted to evaluate the designed terminal guidance law.The results demonstrate that it not only effectively controls the line-of-sight angle to attain the targeted value but also significantly reduces the missile’s mean miss distance to within 1 meter.Compared to the conventional biased proportional navigation law,it notably decreases the required terminal overload and enhances the missile’s guidance accuracy.Furthermore,by directly incorporating seeker measurement information,the proposed guidance law contributes to simplifying the complexity of the guidance system,offering significant reference and application value for advancing research in air defense missile guidance technology.