Design Of Die-cutting Machine Control System Based On Velocity Field

In the printed products manufacture process,die-cutting machines play an important role.The grade,labeling and added value of the product can be improved with the processing of the die-cutting nachine.In this thesis,the die-cutting machine is taken as the research object.The velocity field control algorithm is studied to realize the contour control with the synchronization of multi-axis of the cutting system,and to realize the cutting task of cutting any pattern,Firstly,the mathematical model of the die-cutting machine is established.The mathematical model of the ideal DC servo motor is established.And position,speed and current three closed loop controller is designed to realize the single-axis closed loop servo control.A continuously differentiable friction model is applied and a friction compensation feedforward controller is designed.According to the mechanical structure of the die-cutting machine system experimental platform,the dynamic model of die-cutting machine was established based on the drive axis coordinate system.Secondly,the passive velocity field is studied.Based on the analysis of simulation,the problems of cutting polygons and circles are discovered.The overshooting at the corners of the polygons is discovered.When cutting circular patterns,the “radial reduction” phenomenon will occur.In order to improve the accuracy of cutting,two new types of velocity field for polygons and circle are proposed.The simulation results show that the coutour controller based on the new velocity field can reduce the overshooting at the corners and suppress the “radial reduction” phenomenon,so that the contour accuracy of the system is improved.Finally,the die-cutting machine system experimental platform is designed and studies experimentally.Based on STM32F407,the main control board and software system of the die-cutting machine is designed.The new velocity field control algorithm is applied to realize functions such as motor drive and control,signal acquisition and G-code file analysis.Based on STM32L152,the human machine interaction is designed to realize functions such as communication with main board,data presentation and manual control of die-cutting machine.The results of experiment data of uniaxial servo experiments and biaxial cutting pattern experiment show thar the pattern is free of burrs,distortion and misalignment.The effectiveness of the algorithm is proved.