A novel second-order sliding-mode-based impact angle and autopilot lag guidance law for engaging manoeuvering targets with unknown acceleration is presented in this study. A backstepping technique is applied to the design of the sliding surface. The proposed guidance law is based on a new sliding surface. It exhibits the advantage of ensuring that the sliding surface and its derivative will converge to zero in finite time while guaranteeing that the sliding surface will not cross zero until the ultimate time. The method effectively eliminates the undesired chattering of the sliding surface. To compensate for the uncertainty caused by target manoeuvering, a new observer is developed to estimate target manoeuvering. The convergence of the system is proven through a Lyapunov function and finite time convergence theory. Lastly, mathematical simulations results show that the proposed guidance law can achieve precise interception with a wide range of impact angles, thereby verifying the effectiveness of the guidance law.

中文翻译：

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考虑自动驾驶滞后的具有碰撞角约束的新型二阶滑模制导律用于拦截机动目标

本研究提出了一种新颖的基于二阶滑模的冲击角和自动驾驶滞后制导律，用于以未知加速度接合机动目标。反推技术应用于滑动面的设计。所提出的制导律基于一个新的滑动面。它的优点是保证滑动面及其导数在有限时间内收敛到零，同时保证滑动面直到最后时刻才过零。该方法有效地消除了滑动表面的不希望的颤振。为了补偿目标机动造成的不确定性，开发了一种新的观测器来估计目标机动。通过李雅普诺夫函数和有限时间收敛理论证明了系统的收敛性。最后，