Research On The Control System Of Micro-jetting And Bonding Forming Equipment Based On STM32

The control system of micro-jetting and bonding forming equipment has an important influence on forming precision and forming efficiency.As an important part of the equipment,the control method of accurate and on demand ejecting of the printhead is complex,which increases the difficulty of the development of the control system and prolongs the development cycle.Therefore,in this topic,a control system based on STM32 is developed for the independent-developed micro-jetting and bonding forming equipment,which combines with the printhead and the corresponding control components of the commercial piezoelectric inkjet printer.Based on the analysis of the operating characteristics of each device,the corresponding control scheme is designed.The Y axis motion of ejecting device matches with the X axis of printhead through the detection and analysis on ejecting device’s working state signal.The proper speed and positioning precision of the motion device are analyzed and calculated to provide the basis for the subsequent development of hardware and software of control system.The temperature control strategy based on PID is adopted to realize the rapidity and accuracy of temperature control.The hardware circuit of control system is developed.The hardware circuit uses STM32F103VBT6 as the control core,including the minimum system module circuit,ejecting device state detection and feedback module circuit,motion control module circuit,temperature control module circuit and the serial communication module circuit.And the functional interface circuit is set aside for function expansion of equipment.Software program of control system is developed.Ejecting device state detection and feedback program is developed based on the analysis on the printing process of equipment.According to the motion mode and requirements on speed and accuracy of each motion device,the motion control program is developed,including the Y axis motion control program,laying powder motion control program and forming table lifting motion control program.PID temperature control program based on STM32 is developed,including temperature detection program and heating and cooling control program.Serial communication control program is developed to realize the communication between PC and hardware.The forming experiments of bevel gear and impeller are carried out by using the control system to drive the equipment.And the 72 hours continuous operating test is carried out.During the operating test,the equipment runs smoothly.The printing speed of the control system to drive the equipment is about 25 seconds per layer,and the forming error is less than 0.2mm.