Its 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.
Description of Rapid Prototyping
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.
These 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.