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As the name indicates, rapid prototyping (RP) has traditionally been used to provide a physical representation of a product in a relatively short time. RP is performed by either material removal or material addition. In material-removal type RP processes, the part is produce by machining it is out of a block of material; mainly using computer numeric controlled (CNC) machining centers. In material-addition type RP, the prototype is made by adding layers of materials using one of the available RP technologies.

Earlier prototyping materials and technologies were used to provide product designers with the ability to visualize the product, but with limited ability to assess the functional performance of the product. Nonetheless, prototyped parts also need to allow for design validation (assessment of the mechanical and physical behaviors); which indicates that the prototyping material should have the same characteristics as the production material. This was only available in limited situations where the prototyped parts were made using removal processes, casting processes, or metal spray deposition. However, recent advances in rapid prototyping technologies have allowed the use of production type polymers that can be used to assess the functional behavior of these materials.

One of the shortcomings of testing prototyped products made of production type materials is that the material structure and the mechanical response of the prototyped part may not match those resulting from conventional processing (forming, molding, etc.) that is used to fabricate the actual product. This is caused by differences in processing conditions between RP and conventional processing. For example, if metal spray deposition is used for rapid prototyping purposes, the microstructure and level of porosity in the prototyped part are likely to be different from those of a cast or stamped product of the same size and shape.

Therefore, the goal of this chapter is to provide an introduction to structure and properties of engineering materials, testing methods used to determine mechanical properties, and techniques that can be used to select materials for material-addition type rapid prototyping.

Automatic feature recognition from CAD solid systems highly impacts the level of integration. CAD files contain detailed geometric information of a part, which are not suitable for using in the downstream applications such as process planning. Different CAD or geometric modeling packages store the information related to the design in their own databases. Structures of these databases are different from each other. As a result no common or standard structure has been developed so far, that can be used by all CAD packages. For that reason this chapter proposes an intelligent feature recognition methodology (IFRM) to develop a feature recognition system which has the ability to communicate with various CAD/CAM systems. The proposed methodology is developed for 3D prismatic parts that are created by using solid modeling package by using constructive solid geometry (CSG) technique as a drawing tool. The system takes a neutral file in Initial Graphics Exchange Specification (IGES) format as input and translates the information in the file to manufacturing information. The boundary (B-rep) geometrical information of the part design is then analyzed by a feature recognition program that is created specifically to extract the features from the geometrical information based on a geometric reasoning approach by using object oriented design software which is included in C++ language. A feature recognition algorithm is used to recognize different features of the part such as step, holes, etc. Finally, a sample application description for a workpiece is presented for demonstration purposes.

This chapter is designed to introduce an exciting image data representation standard known as DICOM (Digital Imaging and Communications in Medicine) in medical imaging community. DICOM is a global information standard that is used and soon will be used by virtually every medical profession that utilizes images within healthcare industry. It is designed to ensure the interoperability of systems used to produce, store, display, send, retrieve, query, or print medical images such as computed tomography (CT) scans, Magnetic Resonance Imaging (MRI), and ultrasound. DICOM Standard has also been developed to meet the needs of manufacturers and users of medical imaging equipment for interconnection of devices on standard networks. The daily operations of DICOM Standard are currently managed by the National Electrical Manufacturers Association (NEMA). We describe a brief history, structure, current applications, and its potential use as a tool in different industries in this chapter.

This chapter will define the concept of reverse engineering systems that are typically utilized in design and manufacturing environments. We will also develop a taxonomy of reverse engineering systems. Differences between contact and non-contact methods for reverse engineering will be detailed. Commonly used non-contact systems, including active and passive systems, will be detailed. Our focus will be on techniques such as laser scanning and 3D cameras.

This chapter focuses on contact based reverse engineering systems. The major technique that we describe here is the utilization of co-ordinate measuring machines (CMMs). Different types of CMMs available are detailed. In addition the performance parameters of these systems are discussed. This chapter also explains the integration of data acquired from reverse engineering techniques with other design and manufacturing related software systems. This chapter concludes with a brief description of the state-of-the-art CMM technologies.

This chapter discusses how assembly operation analysis can be embedded transparently and remotely into a service-oriented collaborative assembly design environment and how the integrated process can help a designer to quickly select robust assembly design and process for rapid manufacturing. A new assembly operation analysis framework, relevant architecture, and tools are introduced. True competitive advantage can only result from the ability to bring highly customized quality products to the market at lower cost and in less time. Product development has become a very complicated process. Many customers are no longer satisfied with mass-produced goods. They are demanding customization and rapid delivery of innovative products. Industries now realize that the best way to reduce life cycle costs is to evolve a more effective product development paradigm using the Internet and web based technologies. Yet there remains a gap between these current market demands and current product development paradigms. The existing CAD systems require that a product developer possess all the design analysis tools in-house making it impractical to employ all the needed and newest tools. Instead of the current sequential process for verifying and validating an assembly design concept, a new Virtual Assembly Analysis (VAA) concept is introduced in this chapter to predict the various effects of joining to realize a rapid manufacturing environment. The predicted effects provide very important decision information to select a robust assembly design and to reduce unnecessary feedback processes on rapid selection of assembly processes.

This chapter presents a description of how CNC milling can be used as a rapid prototyping process. The methodology uses a layer-based approach for machining (like traditional rapid prototyping) for the rapid, automatic machining of common manufactured part geometries in a variety of materials. Parts are machined using a plurality of 21/2-D toolpaths from orientations about a rotary axis. Process parameters such as the number of orientations, tool containment boundaries and tool geometry are derived from CAD slice data. In addition, automated fixturing is accomplished through the use of structures added to the CAD geometry. The chapter begins by describing the machining methodology, and then presents a number of critical issues that affect making the process automatic and efficient. The CNC-RP process is compared and contrasted to existing RP processes. In particular, we consider the differences in an additive versus subtractive process with respect to accuracy and material choices. The strengths and limitations of rapid machining are illustrated, along with a discussion on the economics of using rapid machining versus additive RP and/or traditional machining processes to create single or small batches of parts.

SIS is a new method of building 3D objects using powder sintering. The method is capable of making plastic parts without the use of laser. An Alpha machine has been constructed and preliminary studies have been carried out to prove the concept and to explore the process variables and their impacts. Various polymers including polystyrene and polyester have been successfully used in our experiments. The approach should be feasible for a variety of polymers.

Contour Crafting is a mega scale fabrication technology based on Layered Manufacturing process (LM). This fabrication technique is capable of utilizing various types of materials to produce parts with high surface quality at high fabrication speed. The process extends its fabrication capabilities to construction of houses and civil structures.

The consideration of whether to adopt rapid prototyping (RP) technology in general or a specific system in particular is not a trivial issue for most organizations. This technology has influences and has implications for a variety of intra-organizational functions and inter-organizational boundaries. The decision issues faced by these organizations include the balancing of needs across the organization and its partners, consideration of tangible and intangible factors, and the consideration of strategic and operational dimensions. In this chapter we introduce some of the categories of attributes and factors that organizations need to consider. The various factors are then evaluated using a multiattribute utility model called the analytical network process. An illustrative example provides insights into the execution of the technique. The technique is useful due to its capability to consider the many relationships and influences among the factors. It is also flexible enough to consider perceptual as well as more objective data and information when analyzing the problem situation.