How Does a 3D Scanner Work?

Many digital engineering strategies that enable the future of product development, manufacturing, quality control, and production begin with 3D scanning. 3D scanners work with advanced technology and specialized software to create a tool that delivers game-changing results. For those still working with mechanical tools and traditional coordinate measuring machine (CMM) technology, 3D scanners work as an easy gateway to advanced manufacturing and engineering strategies. Keep reading below to understand more about how 3D scanners work and what the technology is capable of so you can begin accessing its benefits now.

Understanding How a 3D Scanner Works

A 3D scanner works by capturing data from a physical object's surface to describe its shape in an accurate, digital, three-dimensional format. Unlike measurement data from a CMM, high-quality 3D scan data is used for more than just inspection and dimensional analysis. The resulting measurement data enables faster, more accessible digital analysis and inspection in a visual, in-depth reporting method. 3D scanners also work to replicate parts in reverse engineering, assure fit, form, and function of components in remote locations, validate CAD models of 3D printed parts, and open the door to more digital strategies.

What are the Different Types of 3D Scanners?

There are many different types of 3D scanners available for various applications. Creating a digital model of any physical part requires a 3D scanner to collect accurate data to form its geometric identity, but not every type of 3D scanner works for every type of application. For example, if you are a DIY at-home hobbyist, you can make a simple 3D scanner with your mobile phone or make a 3D scanner with a Microsoft Kinect. However, while these 3D scanners work well for fun projects, they won't deliver manufacturing-grade accuracy and detailed requirements. Metrology-grade 3D scanning equipment is necessary for industrial use.

A laser 3D scanner is another type of 3D scanner that uses specialized software and a laser probe to project a laser line along the part's surface while sensor cameras continuously record the changing distance and shape of the laser line, resulting in a collection of XYZ coordinates. While these scanners are a quick way to collect data points from a physical object, other 3D scanners, such as structured light 3D scanners, can collect higher quality data. Structured light 3D scanners have established trust due to their high precision accuracy, which is why they're used widely throughout manufacturing.

How Does a 3D Scanner Work with Structured Light?

A 3D scanner works with structured light using the principles of triangulation. The sensor projects a precise shifting fringe pattern across the part's surface, and two cameras capture the surface geometry based on the pattern distortion, calculating 3D coordinate measurements. The 3D scanner collects and processes millions of X-Y-Z data points into a "point cloud," creating a detailed digital twin of the object. Since the distance between the sensor, cameras, and angles is all known, the principle of triangulation is applied, producing accurate, reliable measurement results.

 
This image depicts how structured light 3D scanners also work with the principle of triangulation. A light source sits between two cameras set angled towards each other, projecting a heterodyne "fringe" stripe-like pattern onto the physical object's surface. The stripes change in size and direction during data collection. The sensing cameras observe the contrast along the stripes' edge and assign those pixels X-Y-Z coordinates, quickly collecting precise, crisp scan data containing very little texturing. The software then transforms the data points into visible data that comprise an accurate, digital replica of the physical part.

How Does a 3D Scanner Work with LED Technology?

Structured light 3D scanners traditionally used white light. Today, different light colors are available, but the most popular are blue light 3D scanners that use LED technology. Blue light helps capture data on shinier and darker colored surfaces and filters out the ambient light present inside labs or on the manufacturing shop floor. The result is a clean, clear, precise data set with low noise.

How Does a 3D Scanner Work for Quality 4.0?

The concept of Quality 4.0 incorporates advanced manufacturing technologies to propel quality processes into the future. Adopting 3D scanning lays the groundwork for these modernized dimensional inspection techniques while overcoming the shortcomings of traditional quality and manufacturing practices. For example, 3D scanners collect data that provides the ability to virtually deconstruct parts and pieces of an object without physically destructing anything. With this data, quality professionals also find problem areas, fix parts, validate and test objects before they're physically in production. The measurement data's high accuracy enables the fast and reliable creation of dimensional calculations such as CAD comparison, sectional analysis, GD&T, trend/SPC, and more.

How Does a 3D Scanner Work for Digital Twin Strategies?

3D scanners work as a tool to access digital twin concepts in Quality 4.0. The data captured with a 3D scanner becomes the physical object's digital twin; therefore, using an accurate 3D scanner matters. 3D scanners work for many digital twin applications, including digital assembly. In this method, engineers connect 3D scan data from multiple parts in remote locations for assembly within the software. The digital assembly process enables you to assess the fit of such components before physical parts are mass-produced and shipped.

How Does a 3D Scanner Work for Reverse Engineering?

3D scanners work for reverse engineering by using scan data from a physical object to create a 3D CAD model for product enhancements and archiving. Legacy parts are often described within two-dimensional drawings, not 3D CAD models. Accurate 3D scanners make it possible to reproduce legacy parts using precise three-dimensional data. The 3D scanner scans the part, and the resulting data becomes a reference to create a 3D CAD model that can be used to develop new molds, tooling, or new parts with the same dimensional characteristics as the original or engineering product enhancements. Good quality 3D scan data with a watertight mesh can also be used to 3D print a duplicate of the original and improves efficiency in the reverse engineering process.

How Does a 3D Scanner Work for Adaptive machining?

Adaptive machining is a trending process popular with aerospace and power generation turbine engine components such as airfoils, blisks, molds, and dies. In adaptive machining, accurate structured light 3D scanners digitize a part's surface geometry and send the data back to process the updated machining tool paths, allowing for real-time adjustments without having to reposition in and out of the CNC machine. This process is used with new parts and parts that need repair to help reduce operating costs and lower cycle times while increasing accuracy.

Find Out if 3D Scanning is a Good Fit for Your Application

If you're ready to learn how 3D scanners will work for your specific application, contact a Capture 3D team member today. Our 3D scanners provide an accurate, reliable solution to the advanced metrology needs of industries with diverse applications everywhere. During an in-person or virtual demo, our team will show you how 3D scanning improves product design, streamlines production lines, improves quality control, and unlocks Quality 4.0 strategies that will elevate your industry to new possibilities.