Output Feedback Control for Pneumatic Muscle Joint System With Saturation Input

Jianping Cai,Feng Qian,Lujuan Shen,Rui Yu

doi:10.1109/access.2020.2991729

Abstract

Pneumatic muscle as a relatively new pneumatic component is often applied to some precise and flexible control systems. The precise control accuracy puts forward higher requirements for the controller design of the pneumatic muscle system. To guarantee good performance, unknown input saturation which seems inevitable must be fully considered in the controller design. In this paper, such a control problem is investigated for a pneumatic muscle joint system with input saturation and external disturbance. The auxiliary signals are introduced to compensate for the effect caused by unknown saturation. Furthermore, a filter is constructed to estimate unmeasured system states. Then an output feedback control scheme has been proposed by these auxiliary signals and states filter. Finally, simulation studies are used to verify the effectiveness of the proposed control scheme.

Highlights

Pneumatic muscle [1], [2] is a new pneumatic component and has been used in precise and flexible control systems due to its good characteristics, for example, light-weight, low cost, high power-weight ratio, and high power volume ratio
Cai et al.: Output Feedback Control for Pneumatic Muscle Joint System With Saturation Input by constructing online estimator, the controller design of systems with input saturation become more and more difficult. To solve such a problem, we consider the control for pneumatic muscle joint system with input saturation and external disturbances in this paper
The main contributions of this paper can be summarized as follows: (I) The control problem is investigated for pneumatic muscle joint systems with input saturation and external disturbance; (II) Filters are constructed to estimate the unknown system states and an output feedback control scheme is proposed to guarantee the stability of systems; (III) In contrast to existing results, the auxiliary signals r1, r2 are introduced to deal with the unknown saturation

Summary

INTRODUCTION

Pneumatic muscle [1], [2] is a new pneumatic component and has been used in precise and flexible control systems due to its good characteristics, for example, light-weight, low cost, high power-weight ratio, and high power volume ratio. J. Cai et al.: Output Feedback Control for Pneumatic Muscle Joint System With Saturation Input by constructing online estimator, the controller design of systems with input saturation become more and more difficult. Cai et al.: Output Feedback Control for Pneumatic Muscle Joint System With Saturation Input by constructing online estimator, the controller design of systems with input saturation become more and more difficult To solve such a problem, we consider the control for pneumatic muscle joint system with input saturation and external disturbances in this paper. The main contributions of this paper can be summarized as follows: (I) The control problem is investigated for pneumatic muscle joint systems with input saturation and external disturbance; (II) Filters are constructed to estimate the unknown system states and an output feedback control scheme is proposed to guarantee the stability of systems; (III) In contrast to existing results, the auxiliary signals r1, r2 are introduced to deal with the unknown saturation.

PROBLEM STATEMENT

STABILITY ANALYSIS

SIMULATION STUDIES

CONCLUSION