NC verification for wire-EDM using an R-map

Abstract

Due to the high complexity and the low speed of the wire-EDM process, it is important to recognize all the possible errors before starting the process. The unproductive and time consuming test runs of wire-EDM NC programs in the real production environment can be avoided by computer graphic simulation. In this paper, a data structure and an algorithm are introduced to verify wire-EDM NC programs through the aid of graphics. The nonparametric R-map model is a special form of discrete surface representation in which the r-values of the surface are given at and points. R-map is used to compare the final workpiece-geometry with the CAD data. The verification and editing system for wire-EDM NC programs is implemented on an IBM/PC-386, and written in c++. The developed system displays the trace of the wire electrode and the coloured end-product. The depth of the product surface colour is proportion to the magnitude of machining errors. The system proves to be a valuable tool in detecting and correcting errors of wire-EDM NC programs. Copyright (C) 1996 Published by Elsevier Science Ltd