Parametric and Structural Optimization of Pneumatic Positioning Actuator

Abstract

Linear positioning actuators are widely used in industry as a convenient means of positioning objects directly without the use of additional motion conversion mechanisms. A significant place among them is occupied by piston-type hydraulic and pneumatic systems. Their application areas are different due to the difference of their power to weight ratio, as well as performance characteristics. One of the most popular applications of pneumatics is in material and small mass object transportation over short distances. In this sphere pneumatics has obvious advantages in power density, speed output response, ecology, cost and other factors. On the other side, the pneumatic actuator is difficult to control due to the compressibility of the working fluid (air), the nonlinearity in the flow phenomenon, sensitivity to changes in parameters, friction forces and other factors. This work is aimed at finding a compromise solution to the problem of harmonization of the contradictions mentioned above. The task is to find the optimal correlation between the systems parameters, compensating for negative properties and allowing the full use of available opportunities. The solution of the problem is based on the results of modeling the dynamics of the positioning pneumatic actuator, presented in a dimensionless form, including the model of the power drive itself, the control system (controller) and the external effects.