Sliding mode control of position commanded robot manipulators. (December 2018)

• Record Type: Journal Article
• Authors: Adhikary, Nabanita; Mahanta, Chitralekha
• Is Part Of: Control engineering practice. Volume 81(2018)
• Page Start: 183
• Page End: 198
• Publication Date: 2018-12
• Subjects: Position commanded servo -- Robust control -- Robot manipulators -- Fast terminal sliding mode -- Backstepping -- Time delay estimation; Automatic control -- Periodicals; 629.89
• DOI: 10.1016/j.conengprac.2018.09.011
• Languages: English
• ISSNs: 0967-0661

Abstract

Abstract: This paper investigates the method of implementing dynamic controller on a manipulator which do not have direct drive joints. A previously proposed torque to position conversion method for servo actuated robot manipulators is used with an adaptive backstepping based sliding mode controller for dynamic trajectory tracking control. The proposed controller uses a nonsingular finite time sliding surface to achieve finite time stability as well as higher tracking performance. To avoid a structurally complex control law as well as obtain partial model independency of the controller, the soft nonlinearities of the manipulator are estimated using the time delay control philosophy where delayed signals are used to estimate the model nonlinearities. The entire system is validated using simulation and experimental studies. Highlights: A partially model free robust controller for robot manipulators is proposed. Backstepping is used to derive a non-singular terminal sliding mode control law. The sliding surface and adaptively tuned gain maintains the controller robustness. Use of dynamic torque to position converter for torque control of position commanded robot.