3D Scanning Defined
3D scanning is the process of capturing digital information about the shape of an object with equipment that uses a laser or light to measure the distance between the scanner and the object. 3D scanning is also known as 3D Imaging, Laser Scanning, Laser Digitizing, and Digital Shape Sampling & Processing (DSSP). 3D scanning can capture data of very small objects all the way up to full size aircraft and buildings. It can be used for reverse engineering, computer-aided inspection, or simply documenting the shape for future use.
What is Digital Information?
The "digital information" that is captured by a 3D scanner is called a point cloud. Each point represents one measurement in space. Lines are used to connect all of the points together into a polygon model. The lines all connect to form triangles. The STL file that drives rapid prototyping equipment is actually a polygon model. Surfaces can be constructed on the polygon model or its shape can be used to help define 3D solid shapes for creating a solid model. Some software such as Rapidform XOR can even create parametric CAD data directly from the scan data. Read more about file output types here
Where is it headed?
The software tools that perform all of this have improved greatly over the last ten years. They can now handle massive amounts of data and perform operations at a very high speed. Their ability to clean up noisy point cloud data, smooth out rough scanned surfaces, and merge separate point cloud scans is more advanced and automatic. This is opening up new applications that were not possible or cost effective even five years ago. Computer-aided inspection takes thousands of times more measurement points than traditional CMM yet costs much less. 3D scanning is being used to document museum pieces or intricate architectural works. It is even being used to document crime and accident scenes. Imagine being able to revisit a crime scene years after it is gone to take exact measurements of the distance between a bullet casing laying on the floor and the hole that the bullet created in the wall.
3D scanning is changing the engineering process. As engineers continue to rethink the way that they design and measure, its use will only increase.