Adaptive Continuous Predefined‐Time Sliding Mode Control for High‐Order Nonlinear System and Application in Electronic Throttle Systems

ABSTRACT This paper introduced a novel adaptive continuous predefined‐time sliding mode control method for fast and accurate tracking control of high‐order nonlinear systems, addressing unknown uncertainties and disturbances. First, we proposed a continuous predefined‐time disturbance observer, designed through the differentiation of the estimated value. Then, a hierarchical predefined‐time sliding surface structure is presented, which consists of a recursive sliding surface and an additional integral sliding surface. Based on the proposed sliding surface, we presented a continuous sliding mode control law, which ensures chattering‐free operation and enables tracking errors to converge within a predefined time. This is achieved through the use of observer information and the introduction of integrator component. To mitigate the impact of observer errors, we incorporated a bidirectional adaptive law. This law updates the switching control gain, ensuring practical predefined‐time stability. The stability of the closed‐loop tracking control system, guaranteed under predefined‐time constraints, was demonstrated and analyzed using the Lyapunov theory. We applied this universal control method to an electronic throttle system, achieving fast and accurate robust trajectory tracking. Comparative experimental and simulation studies with existing sliding mode control methods validated the effectiveness and superiority of the proposed approach.