Research On Digital Control System For Five-axis Compound Machining With Ultrasonic-assisted EDM

With the rapid development of manufacturing, hard and brittle materials, such as glass, ceramics, diamond and other characteristics, have abrasion resistance, high temperature, low density and expansion coefficient, widely used in aerospace, automotive, medical, precision instruments and other fields. But this kind of materials are hard and brittle, so when we use the traditional grinding and polishing process, the efficiency is very low, and even damaged, especially chapping processing of complex structure, which severely limit the efficiency and application scope of hard brittle material. At present, there is often used EDM, ultrasonic machining technology and composite processing technology for processing machining brittle materials.This machining carry out a set composite processing equipment of high-current discharge milling, rotating ultrasonic-assisted grinding, ultrasonic-assisted EDM and conventional milling, This paper describes the design of digital control system for five-axis compound nachining with ultrasonic-assisted EDM.The system uses dual-CPU "IPC + PMAC" to industrial computer platform based, PMAC-PCI motion control card for the movement control center, PMAC pass commands to the motor drive controlling motor movements, grating and the optical encoder constitute a closed or semi-closed loop feedback system, PMAC I-variables can adjust systems PID, positioning accuracy and repeatability of positioning accuracy. All this above ensure the system's efficiency, stability and accuracy. Visual C + + 6.0 language is used as a development tool in Windows environment developing interactive interface. PMAC own internal dynamic link library Pcomm32.dll which can achieve communication between the upper and lower machine. Using a "modular" design approach, the user through the interactive interface who can completed setting the coordinates, position measurement, program editing, milling, ultrasonic EDM, tool compensation, system status detection. The CNC system's hardware and software is designed and developed. Preliminary experiments have done on hard and brittle materials including K9 optical glass and SiC. Proof of the availability and accuracy of the system, and also establish the base for the further research.