The Research Of Hand Stitch Sewing Machine Controllor

Hand Stitch Sewing Machine is one of decorative special industrial sewing machines and mainly suitable for sewing ornamentally suits,overcoats,career appareals,shirts and so on.Because of the complexity of system structure and control process and high precision in Hand Stitch Sewing Machine,the majority of excellent Hand Stitch Sewing Machines are imported from abroad at present.As a typical electromechanical integration equipment,Hand Stitch Sewing Machine’s controller is the core part in it.Therefore,it is necessary to study further Hand Stitch Sewing Machine’s controller.This thesis analyzes and studies the problems of Hand Stitch Sewing Machine such as system structure,function features,control characteristics and the hardware and software design of its controller and so on.This thesis introduces in detail the basic principles and the control methods of the main spindle motor brushless DC motor and the homdecor motor two-phase hybrid stepping motor.The method of soft start of brushless DC motor and the process of acceleration,deceleration and positioning of stepping motor are introduced in thesis.An improved H_PWM_L_ON modulation strategy is applied which makes speed adjustment better.According to function features and system performance indicator requirements of Hand Stitch Sewing Machine,double-closed loop control based on Fuzzy PI control theory is used for speed regulation,and a piecewise Fuzzy PI control theory is put forward which is used to make the motor stop position more accurate in Hand Stitch Sewing Machine during the brake processing.Hand Stitch Sewing Machine controller’s hardware system adopts an ARM plus CPLD architecture,ARM chip uses LPC1768whose kernel is Cortex-M3,or CPLD chip uses high performance-price ratio’s LC4032V.LPC1768is used to control the brushless DC motor and the stepping motor,but CPLD merely commutates the brushless DC motor and manages the peripheral keyboard.Due to the high frequency of commutating brushless DC motor, CPLD is solely used to implement the process of commutation,which can improve the work efficiency of Hand Stitch Sewing Machine greatly.Because the majority of control processes of Hand Stitch Sewing Machine are implemented in ISRs(interrupt service routines),utilizing CPU based on the Cortex-M3kernel can quickly respond to interrupt requests,reduce the waitting time of executing interrupt service rountines and improve the executing efficiency of the interrupt service rountines,which make the control precision of Hand Stitch Sewing Machine more accurate.Intelligent Power Module PS21965is used to drive the brushless DC motor and Stepper Motor Driver YKA2304ME is applied to drive stepping motor.Based on the principle of producing stitches of Hand Stitch Sewing Machine,this thesis implement controller’s software design,mainly including system master control program,Fuzzy PI speed regulation module,piecewise Fuzzy PI motor braking module,the module of acceleration,deceleration and positioning process of stepping motor and human-computer interaction module,the improved PWM modulation strategy based on CPLD and so on.The software design can ensure the fast starting process,the stable speed adjustment,the short braking distance and the accuracy of positioning.After a long run test,the designed controller can meet performance indexes of the control system of Hand Stitch Sewing Machine,and has been well used in industry.