Design And Implementation Of CNC Grinding System For Non-circular Surface Workpieces

More and more decorative materials made of crystal glass have coming into people's life,and the shape are more and more diverse.However,for the contour processing of crystal workpieces,there are still many methods of manual processing and simple mechanical processing in the domestic crystal processing industry,which can not meet the needs of the market.Therefore,for the non-circular surface processing of crystal glass,it is of great practical significance to develop a high-flexibility,high-efficiency,automatic and low-cost crystal CNC grinding system.For this purpose,a NC grinding system for non-circular surface workpiece is developed independently,which combines CAD/CAM technology.Firstly,this paper shows the development status of CAD/CAM numerical control technology and crystal processing industry at home and abroad,and introduces the principle and system architecture of the crystal glass grinding process.The system uses the way of C-axis and Y-axis linkage to control the movement of the workpiece,so that the workpiece surface is always tangent to the grinding wheel,so as to achieve the processing of the non-circular surface of the crystal workpiece.By studying the correlation algorithm of curve interpolation,the time division method is used to interpolate the lines,arcs and elliptical arcs.Then it focuses on how to solve the grinding point problem in the process of tangent point tracking,analyses and compares the principle and characteristics of the commonly used data point fitting algorithm,and finally proposes a new grinding point search method.This method directly searches grinding points in the set of contour interpolation points by successive approximation,and the complicated and cumbersome formula calculation is not required,and the precision also satisfies the system requirements.For better interactivity and ease of use,the system integrates these data processing work into the host computer software.As the main innovation part of the system,the host computer software realizes the information including extracting DXF files,restoring display,and curve interpolation,searching grinding point and downloading data and other functions,which abandons the traditional method of obtaining processing data by hand drawing or manual programming,the system's flexibility,precision and efficiency are improved.The data processed by the host computer is transmitted to the lower computer control system through the CAN bus.This paper adopts the modular design concept to design the hardware part of the lower control system in detail.The STM32F407ZET6 is selected as the CPU,and the design includes the core controller module and power supply module,CAN bus circuit,data storage module,human-computer interaction module,motor control module and JTAG debugging module.Finally,the whole system is tested for function and product The test results show that the whole system can run stably,the product meets the system error requirements,and the processing effect is good.It has the characteristics of high flexibility,high efficiency,automation,low cost,and has broad market prospects.