Experimental implementation of a novel model‐free adaptive fractional‐order sliding mode controller for a flexible‐link manipulator. (21st July 2021)

• Record Type: Journal Article
• Authors: Raoufi, Mona; Delavari, Hadi
• Is Part Of: International journal of adaptive control and signal processing. Volume 35:Number 10(2021)
• Page Start: 1990
• Page End: 2006
• Publication Date: 2021-07-21
• Subjects: adaptive switching control Laws -- finite‐time sliding mode control -- flexible‐link manipulator -- fractional calculus -- GPI observer -- model‐free controller -- smooth trajectory tracking; Adaptive control systems -- Periodicals; Adaptive signal processing -- Periodicals; 629.836
• DOI: 10.1002/acs.3305
• Languages: English
• ISSNs: 0890-6327

Abstract

Summary: This paper presents an experimental study of a robust control scheme for a single flexible‐link manipulator. Regarding the nonlinear dynamics of flexible manipulators and vibration problems associated with these robots, this study aims to propose a novel fractional‐order controller for efficient reference tracking, even in the presence of noise and total disturbances. In this regard, the control term is formulated by adopting the intelligent proportional–integral–derivative (PID) (iPID) technique and sliding mode control. As for estimating unknown states of the system, and ensuring that time‐variable disturbances are well‐handled and they do not excite vibrating modes, the generalized proportional integral (GPI) observer is utilized. Then, the adaptive reaching laws are derived along with the Lyapunov stability analysis, and finite‐time convergence of the sliding surface is proven. Finally, well‐trajectory tracking and robustness of the system are illustrated by the experimental results. The effectiveness of the fractional calculus in terms of accuracy, control effort, and vibration suppression is depicted as well.