Research On The Three Dimensional Laser Cutting NC System Based On PC

3D laser cutting technology has been widely used in aerospace, automobile manufacturing and other industrial fields. Due to the basis of the laser industry in our country is relatively weak, there is a certain gap between our laser cutting equipment and international advanced equipment in manufacturing level and software level. At present, most 3D laser cutting machines in China use the abroad special NC system or secondary developed general NC system, causing the problem of high cost, so the research and development of 3D laser cutting NC system with independent intellectual property rights can meet the requirement of 3D laser cutting NC system and improve the international competitiveness of equipment manufacturing industry in China. In this thesis, A design of 3D laser cutting NC system used the structure of PC+I/O, based on windows platform was provided, the software architecture was designed and the key functions of the system were implemented.Firstly, through the analysis of 3D laser cutting system’s double-controller hardware structure, the software’s functions were classified according to the real-time requirements and operating position. The system was divided into two modules, the level structure and the flow direction of the data was described, and the software architecture was established. In order to realize the coordination control of multi task in NC system, the multi task scheduling architecture of the user management module and the double thread-Interrupt response architecture of the NC kernel module was constructed.The function modules were designed and developed based on the software architecture of the NC system. The basic function modules were developed to realize the common functions of NC system, and the studies of key functional modules were focused. To achieve the unified management of the I/O state and the running condition of the system,and realize logical control function, the Soft PLC module was studied, including the definition of data structure and the operating mechanism of the module. In order to realize the function of network communication of the NC system, the operation mechanism of the network communication module was confirmed, and the communication command and communication parameters were defined. To meet the needs of high speed and precision control, the micro distance interpolation module was studied, including the hardware DDA interpolation algorithm and the servo drive algorithm. In order to improve the speed of cutting and stabilization of the machine, ensure the quality of cutting, the velocity predicting and smoothing module was studied. It presented the motion parameter constraint and trajectory smoothing rule, and realized the speed smoothing algorithm.Lastly, verified the NC system’s multi task scheduling architecture and basic functions by designing machining simulation experiment. To verify the correctness of the Micro distance interpolation module, analyzed the simulation waveform and the waveform of the control pulse collecting from the uniform motion experiment. An example of 3D cutting trajectory was handled by trajectory predicting and velocity smoothing module that developed in MATLAB. The effectiveness of the module was verified by analyzing the result of Velocity and acceleration.