Dr. Hesham A. Hegazi

COMPUTERIZED PHYSICAL MODELING AS A DESIGN TOOL

IN MECHANICAL ENGINEERING

S. Metwalli ¹ , M. Shalaby ¹ , A. Nassef ¹ , H. Hegazi ¹ , A. Ashraf ¹ ,

O. Abdel-Wehab ² and Y. Moussa ²

¹ Professor of Machine Design, e-mail: [email protected], M. Sc. Candidate, e-mail:[email protected] , Assistant Professor, e-mail:[email protected]g, [email protected] ,     [email protected] Faculty of Engineering, Cairo University, Egypt.                    ² NASR Castings Company, Egypt

 Abstract

 The excessive delay of supply of maintenance parts in the Egyptian Industry, prompt the use of modern hybrid technology of reverse engineering methods in capturing the geometrical configuration and fabrication of these parts. Reverse engineering can transform real existing parts into engineering geometric models for the redesign process of parts. Creating geometric models of existing objects for which no such models are available is also invaluable as a design and development tool. This paper presents an approach for reverse engineering of standard shapes, free form curves and surfaces and their intersections. Real parts are captured using 3D-laser digitizer. The pseudo inverse least square approach was used for fitting the captured data to get their geometric models. The new geometric model is exported to CAD/CAM software for implementing any design changes and for getting CNC codes for production. This paper demonstrates the use of the hybrid technology of reverse engineering in the fabrication of mechanical components. The success of the experiment initiated an application to patterns making in support of the casting industry. The presentation will demonstrate the potential of these combined technologies in other fields of engineering, biomedical and monumental applications.