Are 3D printers classified as rapid prototype systems?
Posted by Robert Kiser on Sun, Jan 25, 2009 @ 11:55 AM
Yes, and let me explain why.
When most people think of a printer, the image that comes to mind is a device you print a computer generated document to. I asked some very bright associates of mine what came to mind when I asked them what a 3D Printer is. They all stated it was a device that printed blueprints from 2-Dimensional drawings. I told them they were very warm.
All rapid prototyping systems use a concept to place a 2-Dimensional image on top of another. These processes differ in method per system manufacturer, but the end result is the same. This is an additive process to "grow" a shape that takes up more and more space. It is a physical process that requires that each 2-Dimensional image be somehow "fused" together to create the final solid shape. You might then think that this 2-Dimensional image really isn't 2-D after all, because if you could held it in your hand, it would actually be a 3-Dimensional solid mass. The 2-Dimensional images that rapid prototype systems use to create 3D models are in fact a large (or small) series of 2-Dimensional images, like the images you see on a computer screen. The are referred to as "bitmap" images, and their appearance to the naked eye is controlled by what is termed "resolution". The higher the resolution, the easier it is to see the image. There are software programs in existence that can design an image that is 3-Dimensional in appearance on a computer monitor. This 3-Dimensional image is what is called a "Solid Model". This is where the rapid prototyping process begins.
Once the 3-Dimensional image is complete and ready to be created into a hand held object, some neat things occur. The 3-Dimensional image is saved as a Stereolithography file which is a big series of triangular shapes put together to form the image. This file is then imported into the rapid prototype system's application software and maneuvered around for fastest creation time. When ready, the operator starts the process and the 3-Dimensional image file is sliced up into many of those 2-Dimensional bitmap images I mentioned. So now, our software is acting like a printer at this point. How do we take these images and "fuse" them together into a 3-Dimensional physical objet we can hold in our hand? This is where the rapid prototype system comes in.
The PolyJet is a true 3-Dimensional printer. Think of the PolyJet rapid prototype technology as an overgrown inkjet printer. It holds a liquid inside the jetting heads and jets out each individual 2-D bitmap image, on on top of another. Each 2-D bitmap image is jetted out at a certain mechanical thickness, fused together via ultraviolet light, then machined down to a certain height. This is the point at which a 2-Dimensional bitmap image becomes a 3-Dimensional physical objet.
So, are 3D printers and 3D printing technology rapid prototype systems? Yes, indeed, and the classification is called the "PolyJet" technology and is part of the rapid prototype technologies that exist today.
