3D scanning is an incredible technology that is rapidly advancing alongside 3D printing. However, my personal experience with 3D scanning was nothing to call home about. It was limited to small objects, had poor detail, took forever, and the end result was barely usable. Most often, I could replicate an object by measuring with calipers and modeling it faster than using a 3D scanner. These entry level, consumer-targeted 3D scanners left a lot to be desired, but my opinion on 3D scanning has changed recently as I’ve become more familiar with the technology through our latest partnership with SMARTTECH3D. Today, I am going to help answer a few questions: What is 3D scanning? How does 3D scanning work? What is 3D scanning used for?
3D scanning is the use of a device to create a 3D model of a physical object. Just like how scanning a document or photo creates a two-dimensional digital file, 3D scanning takes physical objects and replicates them as a 3D model that can be manipulated or modified. There is a variety of technologies used to 3D scan objects like photogrammetry, laser scanning, contact-probe measurement, and structured light scanning. All of these methods have their pros and cons, but depending on the quality of the system, are able to create decent models.
SMARTTECH3D uses structured light 3D scanning, which has proven itself to be the most accurate non-contact method of measuring objects in three dimensions. The majority of companies utilizing structured light use blue light scanning to achieve high-quality scans. SMARTTECH3D differentiates themselves by using green light scanning, which has been able to surpass the quality and reliability of blue light scanning so much that they’ve received a certificate of accuracy from the Laboratory of Coordinated Metrology through a rigorous process of independent testing. This level of accuracy and reliability makes their scanners perfect for its two most popular applications: inspection of parts, and reverse engineering.
3D scanning involves a few different steps to go from a physical object to a digital representation. The scanner projects lines of green light of varying width onto the object, and measures the distortion of the light in order to determine what the surface looks like. Using this data, it generates a point cloud, representing the object. A point cloud is exactly what it sounds like: a cloud of points that describes the surface of an object. The point cloud can be edited, usually to remove any noise that doesn’t accurately describe the object. From there, the point cloud is used to generate a triangle mesh. Mesh files in their most common format are STL files – the standard file format for 3D printing. While a scanned STL file can be printed, for best practice, the STL should be used as a tracing object in a CAD program to reverse engineer the object. This will allow the 3D printed object to have the smoothest surfaces and most accurate dimensions possible.
SMARTTECH3D developed their own software called SMARTTECH3D Measure to make the scanning, point cloud editing, and triangle mesh generating as easy as possible. For more advanced reverse engineering and inspection jobs, they offer integration into the Geomagic suite of software.
3D scanning offers an exciting complement to 3D modeling and 3D printing, making our current tools at CADimensions more useful. Personally, I am very excited to find more uses for 3D scanning, and work with our customers to get started using 3D scanning.
