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competiveness, and the requirements push everyone in rapid development. In
such case, Reverse Engineering (RE) techniques are useful. The most important
instruments found in the process, are different scanning systems, which
provides, in a short amount of time, dimensional description in digital concept.
RE has now been accepted as part of contemporary product design and
manufacturing processes. The RE technique is easy defined as the process
which results in creation of a mathematical model from a physical one.
Different cases have different RE requirements, from recovering the
mechanical design information to design based modifications. In case of
extracting the mechanical design information, we will be interested in tolerance,
as opposed to the case of design based extraction where the precedent will be
that of extracting the design intent.
So, the RE methods and techniques are essential because they allow to
capture and digitize an object surface geometry for later use with
CAD/CAE/CAM [1].
2. Product Development Approaches
Nowadays the management of product design can be achieved based on two
methods shown in (Fig. 1), a “conventional approach” and an “unconventional
approach” [1].
The conventional approach in product development using CAD/CAE/CAM
systems, normally starts with geometrical modeling using a CAD system. The
geometric model can be represented by wire frame or as surface or as solid
structure. Generated CAD data, can be exported to a standard format (IGES
points/STL binary, ASCII data, DXF poly line, VDA points or IGES/STL
surfaces) and then imported in the same data format to CAE systems (allowing
numerical model simulation) and/or CAM systems (allowing tools trajectory to
be generated). In a system with a unique database, the design information can
be divided to each application automatically, without manual transfer of data,
each time [3].
In the unconventional approach, we can see that the product development by
the conventional approach is not always applicable when we aim to re-engineer,
simulate or optimize parts/moulds/tools already existing, but without the CAD
data format. So, it will be necessary to apply one technique that allows to
capture part/mould/tool (or prototype) geometry and to generate a numerical
model to be used in CAE and CAM systems. This is called reverse engineering.