Discrete Sliding Mode Control Design for Bilateral Teleoperation System via Adaptive Extended State Observer.

Yongli Yan,Li Ding,Fucai Liu,Yana Yang

doi:10.3390/s20185091

Abstract

The goal of this paper is to improve the synchronization control performance of nonlinear teleoperation systems with system uncertainties in the presence of time delays. In view of the nonlinear discrete states of the teleoperation system in packet-switched communication networks, a new discrete sliding mode control (DSMC) strategy is performed via a new reaching law in task space. The new reaching law is designed to reduce the chattering and improve control performance. Moreover, an adaptive extended state observer (AESO) is used to estimate the total system disturbances. The additional gain of AESO is adjusted in time to decrease the estimation errors of both system states and disturbances automatically and improve the estimation performances of the AESO. Finally, the validity of the designed control strategy is demonstrated by both simulation and experiments. Furthermore, the experimental comparison results indicate that the improvement is achievable with the proposed AESO and DSMC.

Highlights

Nonlinear bilateral teleoperation systems can expand the range of perception, and enable humans to complete complex tasks in a remote operating environment
Since the communication between the master and the slave is achieved through a packet-switched network, this paper focuses on the synchronization control for discrete-time nonlinear bilateral teleoperation system in task space, which includes internal unmodeled dynamics, external disturbance and time-delays
This section addresses a presentation of a proposed control scheme based on discrete-time nonlinear bilateral teleoperation system, where the new adaptive extended state observer (AESO) is introduced to estimate and compensate the uncertainty

Summary

Introduction

Nonlinear bilateral teleoperation systems can expand the range of perception, and enable humans to complete complex tasks in a remote operating environment. The potential applications of teleoperation systems are in the various fields, i.e., the remote handling of hazardous materials [1], underwater maintenance and repairing tasks [2], space exploration [3], telemedicine [4], and so on. In all of these applications, the tasks occur in long-distance and/or hazardous environments. Because of the extremely complicated nonlinearity of the nonlinear bilateral teleoperation systems and the certain constraint conditions on their outputs or states, nonlinear bilateral teleoperation systems havedifficultly in performing ideal performances

Objectives

Results

Conclusion