3D SURFACE PLOT MAPPING FOR FREEFORM USING CNC-CMM

Abstract

The thesis consists of five Chapters, including the introduction, methodological description of the research plan, previous studies on the subject, and the practical studies that included different methods of freeform surface measurement, presenting a proposed method for calculating, and estimating the kinematic errors of three-axis Computer Numerical Control Machine tool (CNC machine tool), this done by analyzing plot mapping of the proposed test-piece, which was machined on CNC machine tool. The proposed test-piece designed and machined using NX 8 Unigraphics CAD/CAM software Package. The three-axis CNC-machine tested by conventional methods (direct and indirect method) in accordance with international standards. The thesis concludes with recommendations and proposed future actions. The use of freeform surfaces in various industry sectors such as the aircraft industry, automobiles and casting molds for engineering products to serve aesthetic purposes or for a technical function has increased, which increases the need to produce more complex and high-precision freeform surfaces to fulfill customer demands. CNC machine tools are the main tool used in the manufacture of freeform surfaces because of their ability to manufacture complex parts with high accuracy, high frequency and cost-effective. The accuracy of the CNC machine tool used is one of the most important factors affecting the accuracy of manufactured freeform surfaces. Determining the kinematic errors of the CNC machine tool is a preferred way to improve the accuracy of the manufactured parts. There are two conventional methods of testing CNC machine tools, indirect and direct method. The indirect method is used to evaluate the performance of CNC machine tools by judging the accuracy of a trial test sample manufactured and measured in accordance with international standards. This method is much easier; however, the kinematic errors are not identified. The direct method in which the Kinematic errors of CNC machine tools are separated and determined using precision instruments such as laser interferometry. The method is more accurate