A disturbance observer (DOB) based-backstepping sliding mode control scheme is discussed for a class of semi-strict nonlinear system with unknown parameters and mismatched uncertainty. Firstly, adaptive technique and DOB are respectively applied to tackle the unknown parameters and mismatched uncertainty, where the DOB can effectively alleviate the chattering problem of sliding mode control (SMC). Then, exponential sliding mode surface is proposed to improve the convergence rate of the sliding mode state. The ‘explosion of complexity’ problem inherent in conventional backstepping control is overcome by designing the novel first-order filter. The stability of the closed-loop system is analyzed in the framework of Lyapunov stability theory, in which the tracking error converges to an arbitrarily small neighborhood around zero (ASNZ). At last, two examples are given to illustrate the effectiveness of the proposed control strategy.

针对一类参数未知且不确定性不匹配的半严格非线性系统，讨论了一种基于扰动观测器（DOB）的后推滑模控制方案。首先，自适应技术和DOB分别用于解决参数未知和不确定性不匹配的问题，DOB可以有效地缓解滑模控制（SMC）的抖振问题。然后，提出了指数滑模面，以提高滑模状态的收敛速度。通过设计新颖的一阶滤波器，可以克服传统反推控制中固有的“复杂性爆炸”问题。在Lyapunov稳定性理论的框架下分析了闭环系统的稳定性，其中跟踪误差收敛到零附近的任意小邻域（ASNZ）。最后，