Chapter 9. Scanning in 3D
“This is all experimental. There is no ‘way.’”
— Bre Pettis
Welcome to the bleeding edge.
You no longer need an expensive high end 3D scanner to create good quality scans that are suitable for 3D printing. There are now an increasing a number of affordable ways to digitize physical objects. Some of them require additional hardware with a RGB camera and depth sensors, like a Microsoft Kinect or a ASUS Xtion shown in Figure 9-1 (see Kinect vs. Asus Xtion for a comparison), but you can also use your phone or a digital camera to capture images. These images can then be converted into 3D models, cleaned up using mesh repairing software and then printed on your MakerBot.
Figure 9-1. The Microsoft Kinect and ASUS Xtion
What is 3D Scanning?
A 3D scanner collects data from the surface of an object and creates a 3D representation of it. The Kinect and Xtion both work by beaming infrared light at an object, and measuring how far away each reflected point of light is. It then turns each individual point into a collection of points called a point cloud (Figure 9-2). Each point in the cloud is represented with an X, Y, and Z coordinate.
This point cloud is processed (or reconstructed) using scanning software into a digitized representation of the object known as a mesh (Figure 9-3). A mesh is similar to a point cloud, but instead of only using single points (or vertices) it ...