Adaptive nonlinear observer–based sliding mode control of robotic manipulator for handling an unknown payload

Abstract

This article presents the control synthesis of robotic manipulators with an unknown constant payload. A novel nonlinear disturbance observer with an adaptive scheme is designed to estimate the external force induced by the unknown constant payload. A general design procedure for designing the gain of the nonlinear observer is developed rather than the time-consuming trials and error to choose proper gain. The nonlinear observer gain is designed using an adaptive technique to extend the applicability of the disturbance observer. The stability of the proposed observer is established using Lyapunov method under certain conditions. The proposed nonlinear disturbance observer will be integrated with the sliding mode control to substantially alleviate the chattering problem. Also, simulation results are presented to verify the effectiveness of the proposed methods.

Adaptive Fuzzy Backstepping Control Based on Dynamic Surface Control for Uncertain Robotic Manipulator

“…In this section, we will illustrate the effectiveness of the proposed controller using a two-link robot manipulator shown in Figure 2 as an example. The two-link robot manipulator is one important simulation object, which is widely adopted in relevant literatures [30][31][32] to show the validity of the proposed method.…”

Finite-time robust stabilization of manipulator system with uncertainty via observer method

“…The main contributions of this article have the following several aspects: (1) Compared with the existing articles based on approximate linearization method on manipulator system in Sayahkarajy 3 and Shivakumar et al, 5 by using the nonlinear model and designing its nonlinear observer, the present article develops several nonlinear results, which implies that the results developed of this article are more difficult. (2) Different from existing literature 14,16,17 based on the error method, by applying extension dimension technique, this article presents two robust stabilization results for manipulator systems with and without uncertainties, namely, the presented method in this article may be applied not only to linear model and approximate linearized model but also to general nonlinear system. (3) In this article, several results of finite time robust stability obtained by observer method are presented.…”

A discrete repetitive adaptive sliding mode control for DC-DC buck converter

“…Huang et al 10 intended an SMC with state and disturbance observers for LCL-Filtered Grid-Connected Inverters with varying grid inductance. An adaptive disturbance observer-based DSMC is proposed for robotic manipulator by Li et al 11 Nevertheless, the aforementioned observer-based DSMC methods made the hypothesis that the disturbance which regroup parameter uncertainty and external perturbation is bounded and slowly time varying. Moreover, these methods can augment system complexity, especially when state and disturbance estimators are simultaneously used.…”