Sliding mode control of the automobile electro-coating conveying mechanism with a nonlinear disturbance observer

Abstract

The trajectory-tracking performance of the automobile electro-coating conveying mechanism is severely interrupted by highly nonlinear crossing couplings, unmodeled dynamics, parameter variation, friction, and unknown external disturbance. In this article, a sliding mode control with a nonlinear disturbance observer is proposed for high-accuracy motion control of the conveying mechanism. The nonlinear disturbance observer is designed to estimate not only the internal/ external disturbance but also the model uncertainties. Based on the output of the nonlinear disturbance observer, a sliding mode control approach is designed for the hybrid series-parallel mechanism. Then, the stability of the closed-loop system is proved by means of a Lyapunov analysis. Finally, simulations with typical desired trajectory are presented to demonstrate the high performance of the proposed composite control scheme.

Disturbance observer–based adaptive integral sliding mode control for the hybrid automobile electro-coating conveying mechanism

“…this article, the Lagrangian-Euler method is used, the general dynamic equations are given by 4 MðXÞ…”

“…In this article, lðxÞ is defined as lðxÞ ¼ YM À1 ðqÞ, pðxÞ is defined as pðxÞ ¼ Y _ q, where Y is the matrix to be designed. 4 Assumption 5. Suppose the NDO is well designed and implemented, the observer (28) is globally asymptotically stable by choosing the observer gain lðxÞ appropriately.…”

“…Suppose the NDO is well designed and implemented, the observer (28) is globally asymptotically stable by choosing the observer gain lðxÞ appropriately. 4,25 The following composite controller is constructed by Theorem 3. The dynamic of the hybrid conveying mechanism (8) will asymptotically converge to the switching surface s ¼ 0 by the NDO-based AISMC algorithm (29) and adaptive law (22).…”

Adaptive Backstepping Sliding Mode Control of the Hybrid Conveying Mechanism with Mismatched Disturbances via Nonlinear Disturbance Observers

“…Many control strategies have been proposed to reject disturbances for parallel and hybrid mechanism, such as proportional integral derivative (PID) control [3], computed torque control [4], fuzzy control [5], robust control [6], backstepping control [7], and sliding mode control (SMC) [8,9]. e abovementioned researches are mainly to deal with matched disturbances.…”

“…However, the robustness could not be attained through the conventional backstepping control method. Recently, SMC has been widely used due to its fast response, easy implementation, insensitivity to parametric uncertainty, and disturbances [8]. us, backstepping and SMC methods have been combined to increase the system robustness against matched and mismatched disturbances.…”