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INTERNATIONAL JOURNAL of ACADEMIC RESEARCH Vol. 4. No. 2. March, 2012

RAPID PROTOTYPING: IMPLICATION FOR
DEVELOPING ECONOMIES

Godfrey Ariavie, Godwin Ejuvwedia Sadjere, Osamudiamen Efosa

Department of Mechanical Engineering, University of Benin, Benin City (NIGERIA)
ariaviefe@


ABSTRACT

Catching up technologically might not be an option for developing economies if they are to remain relevant
in a rapidly changing and dynamic global market. In today’s global market, competitiveness is key to survival. In
order to remain competitive and stay afloat, multinational companies are seeking new frontiers to collaborate and
partner with small to medium enterprises (SMEs) in developing economies as a way of building global value chain
(GVC) which has become necessary to cut production cost, reduce time to market, and produce innovative and
competitive products. One of several technologies that makes low cost of product design and manufacture,
reduced time to market as well as creation of innovative products possible, is the Rapid Prototyping Technology.
The centrality of rapid prototyping technologies to the design objectives of multinational companies building global
value chain makes rapid prototyping technology worth reviewing not only to ascertain its emergence but also to
highlight its implication for developing economies. This paper has done just that.

Key words: Rapid Prototyping, Rapid Prototyping Technologies, Developing Economies.

1. INTRODUCTION

According to the UN, Nigeria is a poor nation. The wealth of a nation is not only measured by how huge its
foreign reserve may be but also by the standard of living of the people of that nation. Although Nigeria is rich in
natural and human resources, six of every ten Nigerians live on less than $$1 a day (NEEDS, 2005). The
government of Nigeria is cognizant of this malady and has been seeking for ways to combat it for several decades.
The standard of living of any nation is reflected in the products and services available to its people. In a
nation with high standard of living, a middle- class family usually owns an automobile, a refrigerator, an electric
stove, a dishwasher, a washing machine, a vacuum cleaner, a stereo, and of course a television set. A nation were
the standard of living is high is said to be a rich nation. This is so not because of the abundance of natural
resources within its territory but because it is able to convert raw materials into manufactured goods, showing that it
has a manufacturing base. Therefore, the more active in manufacturing the people of a nation are, the more
plentiful goods and services become; as a consequence, the standard of living of the people of that nation attains a
high level. On the other hand nations that have raw materials but do not fully exploit their resources are poor and
considered underdeveloped and such is the case of Nigeria. (Coe and Elhanan, 1995.)

1.1. Definition of Rapid Prototyping
Rapid Prototyping [RP] is the term applied to an increasingly important group of materials processing
techniques that enable 3-D CAD models of components and tools to be converted into physical models (Aubin,
1994). It is also the name given to a host of related technologies that are used to fabricate physical objects directly
from CAD data sources. Rapid Prototyping (RP), or Solid Freeform Fabrication (SFF), Solid Freeform
Manufacturing (SFM), Layered Manufacturing (LM), or Desktop Manufacturing (DM), consists of various
manufacturing processes by which a solid physical model of part is made directly from 3D CAD model data, without
any special tooling. This CAD data may be generated by 3D CAD Modelers, CT and MRI scan data or model data
created by 3D digitizing systems (Ashly, 1994).
According to Deitz (1996), prototyping is a process of building pre-production models of a product to test
various aspects of its design. Usually it is slow and expensive. Rapid Prototyping (RP) techniques are methods
which allow quick production of physical prototypes with the important benefits to reducing the Time to Market. By
the use of these techniques, prototypes can be built needing skills of individual craftsmen for no more than just
finishing the part. Furthermore, the resulting design cost will be decreased considerably (Dickens, 1995). Figure 1
is a pie chart showing the worldwide utilization of RP technology and Table 1 shows the historical development of
RP and related technologies.
Fig. 1. Worldwide technological utilization of Rapid Prototyping
(Source: Wohlers Associates, 1995)

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INTERNATIONAL JOURNAL of ACADEMIC RESEARCH Vol. 4. No. 2. March, 2012

Table 1. Historical development of Rapid Prototyping and related technologies

Year of Inception
1770
1946
1952
1960
1961
1963
1988
Technology
Mechanization
First Computer
First Numerical Control (NC) Machine Tool
First commercial Laser
First commercial Robot
First Interactive Graphics System
(early version of Computer- Aided Design)
First commercial Rapid Prototyping System

(Source: Wohlers Associates, 1995)

1.2. Methods of Rapid Prototyping
Existing Rapid Prototyping methods are categorized by the materials used such as photopolymers,
thermoplastics, and adhesives. The Photopolymer systems start with a liquid resin, which is then solidified by
discriminating exposure to a specific wavelength of light. Thermoplastic systems begin with a solid material, which
is then melted and fused upon cooling. The adhesive systems use a binder to connect the primary construction
material. The typical processes are as follows (Wohlers Report, 2004).

1.2.1. Stereo Lithograph
With this method, each layer of the prototype design is generated by exposing the surface of a
photosensitive liquid polymer, contained in a tank, to a laser beam that traces the section. The exposed area
solidifies and is lowered by exactly the thickness of the layer. After all the layers have been generated the part is
post-cured to harden the material. The size of the model is restricted by the size of the tank and typically varies
from 25.40cm to 60.96cm.

1.2.2. Laser Sintering
This Rapid Prototyping process uses a laser beam to solidify particles of a powdered material. After a layer
has been exposed, a new layer of powder is applied and exposed. The unexposed powder also functions as a
support for extended and free floating parts of the model. This process may use a variety of powder materials, such
as PVC, ABS, nylon, polyester, polypropylene, polyurethane, wax, or powdered metals.

1.2.3. Masking Process
With this method a black toner mask is generated on a glass plate which is the negative image of the layer
to be built. A thin layer of liquid polymer is applied to the plate and is exposed to UV light. The unmasked area
solidifies when exposed and is attached to the previous layer.

1.2.4. Fused Deposition Modeling
With this method, a thin plastic or wax like wire filament is fed to a moving head, which traces the area of
the layer and deposits the filament on the surface. Just before deposition, the wire is heated above its solidifying
temperature. Once deposited, the material solidifies and adheres to the previous layer.

1.2.5. Laminated Object Manufacturing
The laminated object manufacturing (LOM) process is an effective rapid prototyping technology with a
variety of application possibilities, it is based on the dispersed/deposit forming principle of RP technology. The main
process of the LOM is as follows: at first, a slice material such as paper is transported onto the work table, the work
table raises, and then a hot beam press and heat up this slice to bind it with the built part; the laser beam which is
controlled by computer will cut this layer along the outline of object shape, and it will cut the rest part beside the
shape into small piece in order to wipe them off after build all layers; after cutting is finished, the work table fall and
repeat the first step.

2. RAPID PROTOTYPING AND DEVELOPING ECONOMIES

Rapid Prototyping is not for large firms only, it also offers tremendous potential for Small to Medium size
Enterprises SMEs to pursue and create new opportunities (Kidd, 1997). Despite of a common thread between the
problems of these companies like limited design and manufacturing capabilities and the benefits offered by the
technology, still a small proportion of industry is in use of this technology and this is particularly true for small to
medium size companies. The general consensus is that less than 20% of the design and product development
community use Rapid Prototyping. In the manufacturing engineering discipline the level of use is far less. It has
been wondered at if the technology is so powerful why few companies use it (Grimm, 2004). There are many
reasons for this low diffusion but the one which largely contributes towards the problem is the lack of awareness on
why a company should use this technology and how to successfully adopt this technology. This sector is totally
unaware about the strategic benefits offered by this technology due to the absence of complete adoption
mechanism. Survey of 262 UK companies showed that 85% of the companies do not use RP and, lack of
awareness is the key factor holding back the RP market. The majority of the group who feels RP is irrelevant have
never searched its application (Grenada, 2002).
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