In this paper, a fixed-time convergence-integrated guidance and control (IGC) method is proposed, which considers terminal line-of-sight (LOS) angle constraint, full-state constraints, and input saturation. Firstly, an IGC design model considering the full coupling of three channels is constructed, and a fixed-time convergence disturbance observer is used to estimate and compensate the unknown disturbances in the model. Secondly, based on the fixed-time stability theory, sliding mode control, and backstepping control, a novel IGC scheme is carried out, and the second-order instruction filter is used to restrict the system states and control instructions. Furthermore, the fixed-time stability of the close-loop system is proved and the expression of convergence time upper bound is given. Finally, comparison simulation and Monte Carlo simulation verify the effectiveness and superiority of the proposed IGC algorithm.

中文翻译：

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多约束三维综合制导与控制设计研究

在本文中，提出了一种固定时间收敛集成制导和控制 (IGC) 方法，该方法考虑了终端视距 (LOS) 角度约束、全状态约束和输入饱和。首先，构建考虑三通道全耦合的IGC设计模型，并采用固定时间收敛扰动观测器对模型中的未知扰动进行估计和补偿。其次，基于固定时间稳定性理论、滑模控制和反推控制，提出了一种新颖的IGC方案，利用二阶指令滤波器对系统状态和控制指令进行约束。进一步证明了闭环系统的固定时间稳定性，并给出了收敛时间上界的表达式。最后，