Cusp geometry analysis in free-form surface machining

Abstract

The measurement of cusp height is the conventional method for determining the amount of excess material on free-form machined surfaces, and is frequently used to justify surface quality at the design and manufacturing stages. Although, such surface assessment strategies are generally accepted by manufacturers and customers, they may not provide enough information to qualify the machined surfaces. The aim of this work is to develop a new surface assessment method, for the machined surfaces by determining the area and the volume of the cusps. The method is built on analytic mathematical models of the surfaces and enhanced by the explicit forms of the cusp area and volume equations. The accuracy and reliability of these analytical formulations have been tested with data from machining trials and comparisons with a commerical software package. The indications are that this new approach offers a more comprehensive surface assessment strategy than the conventional measuring method.