Research And Experimental Analysis Of Synchronous Control Strategy For Dual Drive Two-Dimensional Worktable

As the basic control unit and the key transmission part of precise CNC equipment,the structure and control accuracy of the worktable feed system will affect the performance of precise CNC equipment.Therefore,the research of high precision worktable feed system occupies a very important position in the field of advanced industry and scientific research.The traditional drive mode of feed system is to use a single motor.Because of its poor structural stiffness,the axial driving force is difficult to guarantee the accurate acting on the center of gravity of moving parts.This will greatly affect the accuracy and life of equipment.The dual drive technology based on the center of gravity driving principle adapts dual motor with double screw arranged in parallel to drive component in the single degree of freedom.The dual drive technology improves the stiffness of single drive structure,especially the torsional stiffness,which greatly promotes the accuracy of mechanical equipment and increases the life of transmission device.However,in the process of dual drive feed system,the synchronization control error is very likely to cause system imbalance,so it puts forward high requirements for the synchronization performance and control technology of dual drive feed system.In this paper,aiming at the synchronization error in dual drive feed system,the designed dual drive two-dimensional worktable is considered as researched object.From the two aspects of driving technology and control technology,synchronization error of the dual drive two-dimensional worktable is reduced,and the accuracy and stability of the system is improved.Specific research contents are as follows:1.The overall scheme of the dual drive two-dimensional worktable is designed in this paper,including the design of dual drive feed system,guidance system,double grating ruler detection system.Based on the mechanical structure of the dual drive two-dimensional worktable system,the principle of center of gravity driving is analyzed.This paper also completes the design and selection of the key parts,ball screw and guide rail.2.The mathematical model of permanent magnet synchronous motor and its three-loop is established.Based on the mathematical model of servo feed system,PID master-slave control strategy,traditional PID cross-coupling control strategy and fuzzy PID cross-coupling control strategy are proposed.By comparing the simulation results of the control strategy,the synchronization performance of different control strategies is analyzed.3.On top of the dual drive synchronous control system based on BECKHOFF motion controller,the scheme and key hardware of the dual drive synchronous control system are designed.According to the control requirements and drive way,the electronic control system based on EtherCAT communication is designed.And this paper not only completes the assembly and manufacture of the dual drive two-dimensional worktable mechanical system,but also the integration of the control system.4.Based on the functional requirement of dual drive two-dimensional worktable,the dual drive synchronization control software is developed.The user interface design and program coding are completed.Finally the experimental study of dual drive synchronous control system is carried out.By comparing the results of experiment and simulation,the synchronization performance of the system with different dual drive synchronization control strategy is analyzed.