CNC System Design Of Large Thin-walled Parts Mirror Milling Equipment

With the rapid development of science and modern industry of China, large thin-walled parts are widely used as key parts of the complex advanced large-scale equipment in aerospace, national defense, shipbuilding and other major projects. Large thin-walled parts have the characteristics of low structural rigidity, large size, thin thickness, difficult material processing, high precision requirement and so on. At present, the processing methods of large thin-walled parts are usually used in the industrial field, such as forging, welding or precision casting. In order to meet the processing requirements of large thin-walled parts, the project team puts forward the NC milling system based on mirror processing technology to solve the processing problem of large thin-walled parts. Based on this background, this paper mainly designs the CNC system of large thin-walled parts mirror milling equipment, and studies the synchronous control of mirror processing.According to the requirement of large thin-walled parts mirror milling equipment, this paper presents the design scheme of open CNC system which is suitable for the mirror processing of thin-wall parts. Firstly, this paper studies the hierarchical structure and functional characteristics of the open CNC system, and adopts the "IPC+motion controller" type of open CNC system. Then the main circuit and control circuit of open CNC system hardware platform are designed. According to the complex electromagnetic environment of the control cabinet, the scheme of electromagnetic compatibility is designed. Combined with the requirements of mirror milling of thin-walled parts, the safety protection measures through hardware protection and software protection are designed.In view of the synchronous control of the system in the mirror milling processing, this paper simplifies the problem to dual axis synchronous control, and puts forward the corresponding solutions. Based on the classical synchronization control strategy and intelligent algorithm, this paper designs a cross-coupling synchronous controller based on fuzzy self-tuning PID, which has good performance in the MATLAB/Simulink software platform.Finally, in order to verify the feasibility and effectiveness of the proposed synchronous controller, this paper designs a dual axis synchronous control experiment system based on the NC cross sliding table and the LabVIEW software development platform, and the control algorithm is applied to the control of the dual axis servo motor. The experimental results show that cross-coupling synchronous controller based on fuzzy self-tuning PID can reduce the error of the dual axis synchronization error by 65%. Besides, it has good effects on the anti-jamming capability, the response speed and the control precision.