the name given to a host of related technologies that are used to fabricate physical
objects directly from CAD data sources. These methods are unique in that they
add and bond materials in layers to form objects. Such systems are also known
by the names additive fabrication, three dimensional printing, solid freeform
fabrication and layered manufacturing. Rapid prototyping also describes a software
engineering methodology. Rapid prototyping, is the automatic construction of physical
objects using solid freeform fabrication and are used to produce models and prototype
parts.Rapid prototyping takes virtual designs (from computer aided design (CAD)
or from animation modeling software), transforms them into cross sections, still
virtual, and then create each cross section in physical space, one after the next
until the model is finished. It is a WYSIWYG process where the virtual model and
the physical model correspond almost identically.The machine reads in data from
a CAD drawing, and lays down successive layers of liquid or powdered material,
and in this way builds up the model from a long series of cross sections.
layers which correspond to the virtual cross section from the CAD model are glued
together or fused (often using a laser) automatically to create the final shape.
The standard interface between CAD software and rapid prototyping machines is
the STL file format.However, there are currently several schemes such as RepRap
Project. to improve rapid prototyper technology to the stage where a prototyper
can manufacture its own component parts. These technologies offer advantages in
many applications compared to classical subtractive fabrication methods such as
milling or turning.