A new fuzzy self-tuning method for controlling packing pressure of a high-accuracy injection molding machine
WANG Shuo1, YING Ji1, CHEN Zi-chen1, FENG Yu2
1. Zhejiang Province Key Laboratory of Advanced Manufacturing Technology, Institute of Modern Manufacturing Engineering, Zhejiang University, Hangzhou 310027, China; 2. Computational MultiPhysics Laboratory, Department of Mechanical Engineering, North Carolina State University, NC, 27695, USA
According to the poor packing pressure control accuracy of the traditional injection molding machines, this paper presents a new injection system using servo motor-driving fixed pump which can provide different speed with the given injection process. The mathematical models were established based on non-Newtonian fluid dynamics for the hydraulic system and the viscous force of melted plastic between the barrel and screw. Based on the theoretical analysis, a new fuzzy selftuning(FST) method was proposed which combined the advantages of both the fuzzy control and the self-tuning control. The experimental data with packing pressure control showed that compared with the traditional PID algorithm, the FST algorithm has better performance with slighter overshooting, quicker response, shorter transient time and better control accuracy.
WANG Shuo, YING Ji, CHEN Zi-chen, FENG Yu. A new fuzzy self-tuning method for controlling packing pressure of a high-accuracy injection molding machine. J4, 2011, 45(8): 1370-1375.
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