High-speed Data Transmission And Control Algorithm Research Of Laser Cutting Machine

Laser cutting has been found widely using in the manufacturing because of its many advantages, such as the wide-range cutting scale, high cutting speed, narrow cutting kerf, small heat-affected zones, and flexible cutting process and so on. And laser cutting is one of the most consummate technologies.The system of Laser Cutting Machine is a two-dimension manufacture system, using flying light path to transmit laser energy and syntaxis, so through the light pen transmit to the surface of the workpiece, make use of the thermal abrasion effect, finally the stepper motor drives light pen move on X-Y plane, to accomplish the manufacture of nonmetal material. The laser cutting system designed by this project adopted a principal and subordinate structure, divided upper computer and lower computer. The upper computer PC software is responsible for graph and image dispose and data transmission. After receiving the manufacture data of the upper computer, the lower computer DSP in control system processes the data through a series of interpolation and acceleration-deceleration control to translate into the control command of stepper motor and laser, to realize the manufacture of nonmetal material.Recently, with the extension of the application field and high-speed development of computer technology, the graph outline of manufacture workpiece is more and more complicated, the transmission data is bigger and bigger, this needs the higher and higher requirement of the high-speed, reliable, real-time characteristics of the transmission data, also to the manufacture speed and precision. In addition, the interpolation arithmetic is perfect and update endlessly. This needs continuous improvement the performance of hardware and software to meet the requirement. The paper resolves the problems of high-speed, real- time of the process of data transmission with using the USB2.0 interface to realize. It has the advantages of flexibility, conveniention, wide applied range, stable communication, low costs and so on which makes USB2.0 interface become the common interface of PC, specially when the transmission speed reaches 480Mbps, its application range is wider. Aiming at the requirement of high-speed and high-accuracy of complicate manufacture workpiece, the paper puts forward a NURBS curve shape real-time interpolation arithmetic which can ensure the interpolation accuracy and interpolation real-time. Adapted to the NURBS curve shape interpolation, the paper employs the S curve shape acceleration-deceleration control arithmetic which can overcome the disadvantage of the traditional acceleration-deceleration control arithmetic, it can receive the smooth speed and acceleration.First of all the mechanism,characteristic of laser cutting technology and its domestic and external developing present are reported, the background and meaning of selected subjects is treatised.Secondly, the paper is emphasis on introduction of the whole frame of Laser Cutting System,principle of work; illustrates the high-speed data transmission between PC and DSP based on USB2.0 and NURBS curve interpolation and S acceleration-deceleration control arithmetic in DSP control in detail. In the process of using USB2.0 to realize high-speed data transmission, the paper introduces the basic knowledge of USB2.0,the hardware circuit design of the system,the realization of the software and the debugging of USB2.0. In the lower computer DSP control ,the paper illustrates the principle of NURBS interpolation,S curve acceleration-deceleration control and its specific realization.Finally, a summary of the whole thesis work is made, and the developing foreground of the laser cutting technology is forecasted. Certainly, the work what the paper does provides the foundation of theory and experiment for practical application.