Research On The Method Of Controlling Solder Paste Printing Speed Based On Fuzzy PID

Surface Mount Technology(SMT)is the most popular technology and process in the electronics assembly industry.Solder paste printing is the first process of SMT production line.According to historical statistics,more than 70% of SMT production line soldering defects are related to the solder paste printing process.Paste volume is an important indicator to measure the printing quality of the solder paste printing process.Too fast or too slow printing speed has a great influence on the solder paste printing volume.Therefore,it is very necessary to conduct in-depth research on solder paste printing speed control issues.The paper combines the national intelligent manufacturing special project "Mobile Terminal Motherboard Intelligent Manufacturing New Model" project,aiming at controlling solder paste printing volume.Based on PID control theory,the feedback speed control method for solder paste printing is studied.First,the paper analyzes the process flow and production characteristics of the SMT production line.The mechanism of solder paste printing process is studied,and the process parameters affecting the solder paste volume are summarized.The importance of printing speed control to ensure the printing volume is analyzed and clarified.Combining the domestic and foreign research on the status quo of solder paste volume control,based on the PID control theory,a research framework for the feedback control problem of printing speed is proposed.Second,the PID control method of printing speed is studied.Combining the characteristics of the discrete nonlinear and uncertain system and difficult to model accurately of solder paste printing process,based on the fuzzy control theory,the self-adaptive control method for PID parameters of solder paste printing speed is studied.Summing up expert experience and designing fuzzy control rules,a fuzzy parameter adaptive PID controller for printing speed is designed.Finally,modeling and simulating the solder paste printing speed fuzzy PID control method and PID control method,the dynamic adjustment characteristics and stability of the printing speed control method is analyzed.