[MUSIC] All right everybody, welcome back. I hope you're enjoying your new CAD skills, your new fusion skills. I hope you're using the sculpt tool. But let me challenge you guys. Let me go one step further. We've taught you guys how to visualize both with drawing and with CAD tools. But what happens if you build something physical? You build a model out of foam. You build a model out of clay. Maybe you've got a part that you already own, that you want to take from physical to digital. Well, that's where we bring in 3D scanning. How do you get that information from the real world into the digital CAD environment to leverage your new skills there? Colton's going to lead this last module here, so let me turn it over to him. He's going to show you about workflows, and he's going to show you about the tools used to do this. Are you ready to start scanning? Let's go. >> Hey I'm Colton Jackson. I work at the Champagne Urbana Community FAB LAB and its my job to introduce the technology that's available at our lab. I get to hear what ideas patrons have in mind and what they hope to do with the digital fabrication tools available to them. Of course, a lot of people come in asking about 3D printing and what you've learned in this course so far is not far off what you would learn if you spent some time at our FAB LAB. You've learned you can download existing models and hit print. Download existing models and modify them doing CAD tools or use a CAD tool to design a model from scratch. With these methods you're taking digital designs and turning them into physical objects. Once you know that's possible it's not surprising your next question might be how can I go the other direction. How can I make a digital file from a physical object. Maybe you want to create a replacement part. Maybe you've sculpted a prototype from clay and you want to digitize that. Or maybe you just want to make a miniature bust of your friends. In this module, we'll cover several different technologies for turning objects into 3D models. The 3D models we create can be used to measure the dimensions of an object, make copies of parts or people, or even used as assets in a video game or animation. The particular devices that I'll demonstrate in the upcoming videos include the NextEngine 3D scanner. The Microsoft Kinect. The structure sensor for iPad, as well as whatever camera you already have. These devices fall into two categories. Structured light scanners, and photogrammetry. I'll detail the way each technology works. Because if you can understand how the computer is doing the work, you can make better decisions about what technique will work best for you. Let's talk about photogrammetry first, since there's a good chance that's a new word for everybody. This is the technology that allows you to create 3D models without any special hardware. All that's needed as input is photographs. Photogrammetry has a much longer history than the other technologies. It's really about taking measurements from photographs. The techniques for doing this began to be developed soon after cameras were invented. And became important as soon as photographs were being taken by aircraft. Going all the way back to World War I. Mathematicians of the day developed techniques to measure distances without having a reference. With only an understanding of the optics, sensor size, how images are distorted by the lens, and clever trigonometry the size of objects and the distances between them could be determined. You could imagine the military importance of these new photogrammetric strategies. This was done long before computers were able to process images. But today, your laptop can extract thousands of measurements from a set of photos, allowing us to create 3D models using compact cameras, or even camera phones. Since cameras can capture photos of objects ranging from microscopic to geologic, photogrammetry can produce 3D models of grains of pollen, or entire mountain ranges. It's super cool. The software we'll cover in this module will be Agisoft Photoscan and Audodesk 123D Catch. So that's photogrammetry using software to take a set of photographs and generate a new 3D model. The rest of the devices use a technique called structured light scanning. That so called structured light is simply a pattern which is projected from the sensor. The pattern can be a laser line sweeping across an object, as is the case with the next engine. Or an infrared star field that envelops the object all at once. These tools are a little more automated since you're not using your own camera. So you don't have to worry so much about getting the technical details of photography right. You can just set the scanner up and hit go. The only 3D scanners I won't be demonstrating include medical devices that use magnetic resonance or x-rays. Or geologic tools that use reflected sound waves to reconstruct objects buried underground, or the ground itself. [MUSIC] [SOUND]
