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Fundamentals of Rapid Prototyping Liquid-Based Rapid Prototyping Powder-Based Rapid Prototyping
The
competition in the world market for manufactured products has intensified
tremendously in recent years. It has
become important, if not vital, for new products to reach the market as early as
possible, before the competitors. To
bring products to the market swiftly, many of the processes involved in the
design, test, manufacture and market of the product have been squeezed, both in
terms of time and material resources. The
efficient use of such valuable resources calls for new tools and approaches in
dealing with them, and many of these tools and approaches have evolved.
They are mainly technology-driven, usually involving the computer.
This is mainly a result of the rapid development and advancement in such
technologies over the last few decades.
In
product development time pressure has been a major factor in determining the
direction of the development and success of new methodologies and technologies
for enhancing its performance. These
also have a direct impact of the age old practice of prototyping in the product
development process. This book will
introduce and examine in a clear and detailed way one such development, namely,
that of Rapid Prototyping (RP).
Historical
Development The development of Rapid Prototyping is closely tied in with the development of applications of computers in the industry. The declining cost of computers, especially of personal and mini computers, has changed the way a factory works. The increase in the use of computers has spurred the advancement in many computer-related areas including Computer-aided Design (CAD), Computer-aided Manufacturing (CAM) and Computer Numerical Control (CNC) machine tools. In particular, the emergence of RP systems could not have been possible without the existence of CAD. However, careful examinations of the numerous RP systems in existence today, it can be easily deduced that other than CAD, many other technologies and advancements in other fields such as manufacturing systems and materials have also been crucial in the development of RP systems.
3 Phases of
Development leading to Rapid Prototyping Prototyping processes have gone through 3 phases of development, the last 2 of which have emerged only in the last 20 years. Like the modelling process in computer graphics, the prototyping of physical models is growing through its third phase.
Fundamentals of Rapid Prototyping While they are currently more than 20 vendors for RP systems, the method employed by each vendor can be generally classified into the following categories: photo-curing, cutting and gluing/joining, melting and solidifying/fusing and joining/binding. Photo-curing can be further divided into categories of single laser beam, double laser beams and masked lamp. Common to all the different techniques of RP is the basic approach they adopt, which can be described as follows: (1) A model or component is modelled on a Computer Aided Design/Computer Aided Manufacturing (CAD/CAM) system. (2) The solid or surface model to be built is next converted into a format dubbed the “.STL” (STereoLithography) file format which originates from 3D Systems. (3) A computer program analyzes a .STL file that defines the model to be fabricated and “slices” the model into cross sections. The cross sections are systematically recreated through the solidification of either liquids or powders and then combined to form a 3D model.
Liquid-Based Rapid Prototyping Liquid-based RP systems have initial form of its material in liquid state. Through a process commonly known as curing, the liquid is converted to the solid state. The following RP systems fall into this category:
Powder-Based Rapid Prototyping
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