This paper proposes an improved back-stepping control approach and its application to small nonlinear UAV control systems with uncertainties such as external disturbance. Unlike traditional back-stepping control methods, the idea of prescribed performance function (PPF) is incorporated into the control design, such that both the transient and steady-state control performance can be strictly guaranteed. Moreover, we design a novel tracking differentiator to avoid the “differential expansion” problem well caused by the calculation of derivative. Significantly, the function approximators (e.g. neural networks) that are widely used to address the unknown nonlinearities in the nonlinear control designs are not needed. Finally, the numerical simulation verifies the convergence and robustness of the system, and the results show that the control strategy can obtain better transient and steady-state performance.

中文翻译：

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具有瞬态规定性能设计的非线性小型无人机系统的改进后步控制

本文提出了一种改进的反步控制方法，并将其应用于具有外部干扰等不确定性的小型非线性无人机控制系统。与传统的反步控制方法不同，在控制设计中融入了规定性能函数（PPF）的思想，从而可以严格保证瞬态和稳态控制性能。此外，我们设计了一种新颖的跟踪微分器来很好地避免导数计算引起的“微分扩展”问题。重要的是，不需要广泛用于解决非线性控制设计中的未知非线性的函数逼近器（例如神经网络）。最后通过数值模拟验证了系统的收敛性和鲁棒性，