Design And Development Of The Host Computer Control Software For LS-WEDM

With the improvement of product performance and accuracy of machining, LS-WEDM has increasingly played an important role in the field of mechanical machining. As the core of the LS-WEDM machine, the performance of the CNC system decides process quality and process stability of the machine directly. Meanwhile, the research and development of LS-WEDM CNC system is still in the starting stage of our country. So it should be given priority to the development of LS-WEDM CNC system. This paper is about the design and development of the host computer control software for the LS-WEDM, basing on the requirement of research and development of the LS-WEDM CNC system.The system uses the controlling model of PC and motion control card. The host computer carries out non-real-time controlling and the slave-computer carries out real-time numerical control function. The control system is developed by VC++ 6.0 in the Windows system. The function module includes man-machine interface, decoding, process positioning, program compiling, displaying and simulation, machining control and parameter setting module. The man-machine interface which is easy to operate is composed of four mutually independent interfaces, switching to another interface by menu.The user can seek the alignment of machining position easily by functions of seeking end-face and centre circle, returning machining start point, workpiece zero and mechanism zero. Analyzing all the interconnecting style of backlash compensation and the formula derivation of offset and inflexion point calculation, the interconnecting point provides line and arc transition styles. The system achieves to the backlash compensating of machining trace. Machining trace and voltage shape will be drawn real-time in the process of machining. Users can observe machining position and discharge condition all the time.The paper has discussed the principle of rotating at random angle and double-acting function. Analyzing the derivation trace which engendered by the different taper cutting styles and different element combination in the conventional taper cutting. The corresponding method of compensated corner elements is proposed. The methods of element linearization and up and down surface traces projected to up and down wire-frame planar are disserted. Path control of taper cutting is achieved. It uses multithread technology to resolve multi-task problem. The host computer and the lower computer communicate by a serial port communication which compiled by windows API.