Research On Motion Control System Of Digital Inkjet Printer

Along with the growth of the market requirement as well as the progress of technology,digital inkjet printer has gradually occupied the market in the textile printing industry.Digital printing technique changes the mode of traditional printing technology,which has the advantages of high image precision,low pollution,intelligent production,etc.And the ability on the research and development in the domestic-made digital inkjet printer is still in the initial stages nowadays,it is important significance to study deeply the digital inkjet printer.The motion control system of the digital jet printer exerts an important influence on the printing precision.This paper is mainly focused on the motion control system of the print head carriage,the printing substrates and the ink droplets.Firstly,this paper analyzes the development process of digital inkjet printer,and compares the motion control system of the foreign digital inkjet printer.It point out the superiority and give the motion control scheme of the digital inkjet printer.Secondly,the motion servo system of the digital inkjet printer mainly includes the print head motion system and the printing substrates motion system.According to the inkjet printing structure and motion control requirement,the strategy of the motion control systems have been provided.(1)The print head carriage moves forth and back in line direction,which is driven by linear motor.In order to get a stable rate of acceleration and deceleration,the velocity loop servo system with fuzzy PID controller,correcting PID parameters instantaneously using fuzzy control.(2)The motion system of the printing substrates is driven by the permanent magnet synchronous motor.The printing substrate must cooperate with the print head carriage in the vertical to do periodic movement,the position control of the servo system directly affect the printing precision.The servo amplifier is used to control the position and velocity of the servo motor in this paper,which use the principle of the space vector pluse width modulation(SVPWM)with three closed-loop controls of current,velocity and position.(3)The droplet movement curve is parabolic during the printing process,this paper proposes a compensation scheme based on the M/T velocity method to predict the velocity for the droplet deviation of the sampling area,which improve the position accuracy of the ink droplet.Finally,the model of each part of the control strategy is established in the Matlab Simulink environment,the results of the system simulation verify the effectiveness of the control strategy and the velocity stability of the print head and positioning accuracy of the printing substrate are improved obviously.Aiming at the problem that the print head position and the print head carriage velocity will affect the position accuracy of the ink droplet,this paper proposes the calibration method for the print head and the verification method of the effectiveness of the ink droplet compensation scheme.In the software programming,this paper finishes the preparation of some PLC programs and touch screen design of digital inkjet printer.