Finite-time tracking control for uncertain robotic manipulators using backstepping method and novel extended state observer. (2nd May 2019)

• Record Type: Journal Article
• Authors: Chen, Chao; Zhang, Chengrui; Hu, Tianliang; Ni, Hepeng; Chen, Qizhi
• Is Part Of: International journal of advanced robotic systems. Volume 16:Number 3(2019:May/Jun.)
• Publication Date: 2019-05-02
• Subjects: Finite-time control -- finite-time model-assisted extended state observer -- robotic manipulators -- system uncertainties -- tracking control; Robotics -- Periodicals; Robotics; Periodicals; 629.892
• DOI: 10.1177/1729881419844655
• Languages: English
• ISSNs: 1729-8806

Abstract

This article considers finite-time trajectory tracking control problem for robotic manipulators with parameter uncertainties and external disturbances. A finite-time controller that achieves high precision and strong robustness is proposed without the requirement of the exact dynamic model. First, a novel finite-time model-assisted extended state observer is designed to compensate the system uncertainties with complex and uncertain dynamics. Then, a composite finite-time controller is developed for trajectory tracking control with the help of finite-time model-assisted extended state observer. Compared to the classic extended state observer, it is proved that the estimation error of finite-time model-assisted extended state observer can be stabilized in finite time. Meanwhile, the finite-time convergence of the closed-loop system with the proposed controller can also be proved through Lyapunov's stability theory. A variable structure term is employed to compensate the estimation errors of finite-time model-assisted extended state observer. The validity of the control scheme is demonstrated by simulations and experiments.