Practical Design of a Sliding Mode Controller for Pneumatic Actuators

Abstract

Pneumatic robot manipulators are characterized by high-order, time-variant actuator dynamics, nonlinearities due to compressibility of air, external disturbances such as static and Coulomb friction, and wide range of payload variations. Conventional PID controllers suffer from problems of gain tuning under these conditions. In this paper, a new control algorithm is proposed for the position and trajectory control of pneumatic actuators based on the sliding mode control approach. The stability of motion is proved for the case of a linear, time-invariant switching surface. A disadvantage of using sliding mode control for third- and higher-order mechanical systems is the need for acceleration feedback. In this paper, to overcome this difficulty we propose the use of differential pressure. The proposed controller is simple, easy to implement, and robust to payload and parametric variations. The effectiveness of the new scheme for position and trajectory control is illustrated by experiments on an industrial piston-driven cylindrical actuator with proportional valves.

A high-accuracy trajectory following controller for pneumatic devices

“…For instance, Drakunov et al [28] developed an interesting control architecture that integrates different techniques for the mechanical and the pressure dynamics: a VSC controller is used for the pressure dynamics and a nonlinear state feedback is used for the mechanical dynamics. Other studies using VSC controllers where developed by Pandian et al in [29] and by Richer and Hurmuzlu in [30]. It is also possible to find applications of high-order sliding mode controllers [31] in pneumatics, for example in the study developed by Smaoui et al in [32].…”

Optimal Control of Penumatic Manipulators for Construction Application

“…The problem of the optimal control is reduced to a determination of necessary elements of the matrix Р, which can be obtained from the equation (5). For such a purpose a solution algorithm of the equation (5) for stationary systems with infinite time of observation [9] can be used.…”

“…A stability of this controlled motion is not guaranteed. It was concluded in [5] that the thirdorder control provides a practical choice for effective control of industrial pneumatic manipulators. Sometimes, in practice, it is impossible to measure a full phase vector because of design parameters of the manipulator [6].…”

Positional control of pneumatic manipulators for construction tasks

“…It was concluded in Ref. [5] that third-order control provides a practical choice for effective control of industrial pneumatic manipulators. Sometimes, in practice, it is necessary to have minimum control energy consumption for autonomous manipulators.…”