Intelligent CAD Tool to Solve Challenges in the Design of Orbiting EDM Electrode 2011-01-1073

Orbiting EDM introduces additional electrode motion to enhance debris removal mechanism during machining process. This method offers superior machining quality towards static EDM due to advancement of debris removal and subsequently becomes a common process to produce precise and complex parts. However, designers often encounter difficulties to design electrode used for orbiting purposes. Aside from adjusting the electrode for machining overcut, the electrode also has to consider for the chosen orbit motion into geometry design, otherwise the final product will not meet design requirements due to deviated product dimension. These two factors have to be adjusted concurrently, following the characteristic of spark machining influenced by orbital motion. There is no CAD package that currently supports geometry adjustment for orbiting motion of EDM process in the market. Therefore, designers always perform manual electrode compensation for both orbit motion as well machining overcut. Manual compensation for both factors is considered as a big challenge for parts possesses intricate geometry, prone to human-error and consumes huge amount of design time. This research aims to facilitate those difficulties encountered on tool design process using the principle of inverse Minkowski sum. A detail explanation about electrode design steps and its validation is presented in the paper. This algorithm is integrated and developed in commercial CAD software as an intelligent tool to automate the electrode design process. Several samples of automotive parts with complex geometry are tested with this tool. The developed tool facilitates an easy process for compensating machining overcut and orbit motion simultaneously, cuts excessive electrode design time, also avoid geometry failure caused by human-error on manual design with promising result.