This paper investigates the problem of designing angle constraint guidance law against unknown maneuvering targets based on discrete-time sliding mode control theory. Invoking the fact that the future course of action of the target, an independent entity, cannot be predicted beforehand due to its complexity and unpredictability, a model-assisted discrete-time disturbance observer in cooperation with a singularity-free strategy is proposed first to estimate the target maneuver. Based on the reconstructed signal and a fast convergence time-varying sliding surface, a new chattering-mitigated super-twisting-like discrete-time impact angle constraint guidance law is then synthesized. Stability analysis shows that the closed-loop system trajectory can be forced to enter into a small region around the sliding surface. Simulations and comparisons with classical discrete-time sliding mode guidance law validate the effectiveness of the proposed guidance law.

中文翻译：

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模型辅助目标机动估计器的离散时间角度约束拦截

本文研究了基于离散滑模控制理论的针对未知机动目标的角度约束制导律设计问题。考虑到目标（一个独立实体）的未来行动过程由于其复杂性和不可预测性而无法预先预测这一事实，因此首先提出了一种模型辅助离散时间扰动观测器与无奇点策略的协作，以进行估计目标机动。基于重构信号和快速收敛的时变滑动面，合成了一种新的抖振减轻的超扭曲样离散时间冲击角约束导引律。稳定性分析表明，可以迫使闭环系统轨迹进入滑动表面周围的小区域。