Study On Motion Control Of Numerical Control For Die-Sinking Micro Electrical Discharge Machining Based On PMAC

Electrical discharge machining (EDM) is one of the non-traditional machining processes. EDM is based on thermoelectric energy between the work piece and an electrode. A pulse discharge occurs in a small gap between the work piece and the electrode and removes the material from the work piece by melting and vaporizing. There are various types of products which can be produced using EDM such as dies, moulds, tools, parts of aerospace, automotive industry as well as micro components. With the development of internet technology, aerospace technology, material technology, numerical control (NC) for EDM become sophisticated increasingly. The NC for EDM is derived from other traditional NC for cutting, but different from it for distinctiveness during processing. In this paper, the motion control system of NC for micro sinking-die EDM based on programmable multi-axis controller (PMAC) is designed, the debugging methods of system and the characters of motion control are suggested, the study about effect of the motion control system of NC for micro die-sinking EDM based on PMAC is carried out.Firstly, the principle and mechanism of EDM and the structure of various EDM are introduced. The system components, traits, application and classification of motion control are presented. The characters of micro EDM and its requirement to motion control are discussed.Secondly, an overall design of the motion control system is taken after the PMAC's hardware and software structure is introduced. According to the characters of PMAC, the software and hardware architecture of NC for micro sinking-die EDM based on PMAC are constructed. To improve dynamic performance, the debugging methods of motion control system are proposed.Thirdly, the characters of motion control and its effect on machining are analyzed during machining. In order to improve stability of motion control and decrease geometric error and motion delay, a static velocity planning based motion control strategy of NC for micro sinking-die EDM is presented. Experiments show that the motion control strategy based on static velocity planning is feasible, stable and reliable.Finally, the effects of machining motion and dynamic performance parameters on EDM are discussed. Given machining condition, the optimal motion parameters are presented. Motion control system based on PMAC is available for more precise position actuary, shorter response time and faster motion velocity. Experiments show that it not only meets demand of micro EDM to motion control system, but also has significant advantages to improve machining stability and efficiency. Multi-Axis Controller (PMAC)...