Prediction of Positioning Accuracy and Settling Time of Double Acting Single Rod Pneumatic Cylinder Using SIMULINK

Abstract

Pneumatic Systems are widely used in industries for a variety of manufacturing processes and conveyor-based automation for lighter payloads. Actuator’s position-holding ability, along with ease of maintenance and cleaner medium, makes them the right choice for low-cost automation. The accurate, repeatable, and instantaneous position control of the actuator is required in such applications. Different configurations of pneumatic systems can be built using different orientations of cylinders. Due to the inertia of the actuator and the compressibility of air, it is difficult to predict the actual position of the piston rod at an intermediate position of the Directional control valve. Hence, the accurate estimation of the piston rod is significant. In this paper, an optimized mathematical model concerning the position of the actuator is developed using the transfer function approach. The paper also presents a model-based technique for prediction of positioning accuracy and Settling time of double acting single rod pneumatic cylinder for horizontal and vertical orientations using SIMULINK®. The mathematical model will be useful to predict the instantaneous position and settling time of the cylinder at a given orientation. The paper also comments on the trade-off between the accuracy and stability of pneumatic actuators at these orientations. The quantitative model can be used by the industry and researchers for achieving accurate position control and minimal settling time in industrial applications such as palletizing, stacking, and pneumatic press for better productivity and throughput.