In this article, a novel almost fast finite‐time adaptive tracking control scheme is proposed for a class of full‐state constrained pure‐feedback nonlinear systems based on barrier Lyapunov functions (BLFs). First, by employing the mean value theorem, the pure‐feedback systems are converted to the strict‐feedback structure with nonaffine terms. Then, by fusing adaptive backstepping technique and BLFs, the design difficulties caused by the nonaffine terms and full‐state constraints are overcome. Furthermore, according to the predeveloped almost fast finite‐time stability criterion, it is proved that the tracking error can converge to a small compact set and all signals of the closed‐loop system can be bounded in an almost fast finite time. Finally, a simulation example of a single‐link robot is presented to verify the effectiveness of the proposed control scheme.

中文翻译：

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一类全状态约束纯反馈非线性系统的几乎快速有限时间自适应跟踪控制

本文针对一类基于势垒Lyapunov函数（BLF）的全状态约束纯反馈非线性系统，提出了一种新颖的，几乎快速的有限时间自适应跟踪控制方案。首先，通过使用平均值定理，将纯反馈系统转换为具有非仿射项的严格反馈结构。然后，通过融合自适应反步技术和BLF，克服了由非仿射项和全状态约束引起的设计难题。此外，根据预先开发的几乎快速的有限时间稳定性准则，证明跟踪误差可以收敛到一个小的紧集，并且闭环系统的所有信号都可以在几乎快速的有限时间内被限制。最后，