A computer aided machining system for the manufacture of three-dimensional surfaces

Includes bibliographical references.This thesis describes the design of a computerised system for machining three-dimensional surfaces, more specifically "sculptured surfaces", using an IBM PC and a Bridgeport 3 axis Computer Numerically Controlled (CNC) Milling Machine. There was a twofold objective to the project: To design and develop a milling system; To provide a teaching tool for undergraduate students who wish to further their studies in the concepts of Computer Aided Design and Manufacture (CAD/CAM). Five broad areas are covered: 1. The development of a mathematical algorithm to approximate a sculptured surf ace represented by a set, of surface datapoints in the form of XYZ coordinates. 2. The development of an algorithm to calculate the toolpath to machine the sculptured surface. 3. The development of an algorithm to display the surface and toolpath in three dimensions on the computer screen. 4. The development of an algorithm (the postprocessor) which translates the toolpath into a program suitable for use with the CNC milling machine. 5. The development of a communications algorithm for the direct transmission of the CNC program from the IBM microcomputer to the memory of the CNC computer