R_Bibb_Medical_Modelling_The_Application_of_Adv.pdf

5.1 Background to rapid prototyping
5.1.1 Introduction
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Physical reproduction – rapid
prototyping technologies
Rapid prototyping (RP) is a phrase coined in the 1980s to describe
new technologies that produced physical models directly from a threedimensional
computer-aided design of an object. Many other phrases have
been used over the years, including solid freeform fabrication, layer additive
manufacturing, 3D printing and advanced digital manufacturing. In the
late 1990s, the application of these technologies to tooling was investigated,
and the phrase ‘rapid tooling’ was commonly used to cover these direct and
indirect processes. More recently, these technologies have been applied to
product manufacture as well as prototyping, and the phrase ‘rapid manufacturing’
is increasingly used to describe this kind of application. Perhaps
the most accurate phrase would be ‘layer manufacturing’ as this covers all
of the processes and distinguishes them from previous technologies such as
machining. However, despite all of the different applications the phrase RP
has been adopted by the industry to cover all these technologies and their
applications and it is, therefore, the one used here.
The objects created by RP processes may be used as models, prototypes,
patterns, templates, components or even end use products. However, for
simplicity, the objects created by the RP processes described in this chapter
will be referred to as models, regardless of their eventual use.
5.1.2 A brief history of RP
Processes that build models directly from computer data have come to be
generally referred to as RP prototyping techniques. RP systems were originally
developed in the 1980s as a method of building exact physical models
of products and components designed using computer-aided design. Initial
applications concentrated on the automotive and aerospace sectors, as these
industries fi rst exploited what were, at the time, expensive CAD/CAM
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