A Research On Proportional Valve-based Pneumatic Positioning Control Of Linear Actuator

Pneumatic position control system is one of the approaches realizing automatization. Because of low cost,high efficiency,no pollution,it has been widely used in many fields of mechanism,chemistry and medicine.However,because of the inherent strong linear feature and the influence of friction,it's very difficult to achieve ideal result of perfect precision and stability,restraining its further application in the industry.Therefore,focusing on the pneumatic positioning system,the study should improve,through the suitable method of control,the cushioning characteristic,realize the arbitrary positioning as well.It certainly has been the hot and practicable area of research,it has very important academic value and practical significance.The main research contents and the major work in this topic:1,We take gas dynamics as a base,use some known theorems and laws such as law of thermodynamics,law of conservation of energy,second law of Newton and pass through several rational and necessary assumption and simplification,and take the basic status equation of controlled subject by deduced as the basic.2,By means of powerful Simulink nonlinear modeling function,built a firenew nonlinear model of straight line cylinder position control system based on the proportional directional valve.3,We utilized linearization tools of Simulink to linearly treat at concreted operating point for the system model,and afforded reference to the parameters setup of PID controller.4,It determined the BP Neural Network-based PID control strategy and obtained the satisfactory control effect.5,We use AMESim and MATLAB / Simulink co-simulation technology,building systems for the further simulation analysis,simulation and performance prediction results show the method is efficient in the whole stroke at any position of the cylinder stroke;and to achieve precise positioning and fast response;and a good result has been achieved in the pneumatic linear cylinder positioning control;and verify the correctness of the model and the effectiveness of control systems.6,This topic still was at the fundamental research stage,will be supposed to carry on the experiment to its research results to confirm,enable it invest to the industrial production as soon as possible.