What is 3D scanning?
3D scanning is the process of digitizing a physical object into three-dimensional space. The resulting STL file contains a digital blueprint with geometric coordinate positions. The resulting digital twin unlocks many digital engineering capabilities, including reverse engineering and inspection for dimensional analysis.
Who Uses 3D Scanning?
Technicians, architects, mechanics, engineers, and hobbyists typically use 3D scanning. But as 3D scanning continues to become mainstream, its capabilities also continue to expand, and more industries are now tapping this advanced metrology technology for its advantages. Despite the expansion of 3D scanning uses, manufacturers and engineers are still most likely to use 3D scanning in their jobs daily.
What's the Difference Between Long-Range and Short-Range 3D Scanning?
Long-range 3D laser scanners capture the geometry of large spaces or objects, such as a building, in one scan, which is then combined with multiple scans as a point cloud to create a digital twin of the environment, object, or structure. Generally, a long-range 3D scanner is necessary when the subject is more than one meter away from the scanner. Industries including aerospace, power generation, architectural, civil engineering, and construction use this 3D scan data for various purposes.
Short-range 3D scanners are useful when an object is within one meter of the scanner. These scanners include contact and non-contact. Typically, a short-range 3D scanner is good to digitize objects ranging in various sizes from a tiny gear to a full-size aircraft. Therefore, it's popular with manufacturing and engineering applications such as dimensional inspection, reverse engineering, rapid prototyping, CFD/FEA analysis, and beyond.
3D Scanning Principles- How Does a 3D Scanner Work?
3D scanners generally work by employing lasers, light, or sensors to detect the surface of a physical object and assign data points to the location of that surface. Those data points blanket the surface(s) of the part three-dimensionally and are collected and compiled to digitally recreate the object with high accuracy and detail. One very popular short-range 3D scanning solution is structured light technology using two high-end cameras and a projector. This non-contact method displays a fringe pattern across the object's surface, and as the pattern shifts, the cameras collect data from the object's surface. This technology originally started with white halogen light but now has advanced to blue LED. The bright light source helps with capturing data on shiny and dark-colored surfaces. These 3D scanners are highly accurate and use the principles of triangulation. The modernized version is Triple Scan technology, which combines high-resolution images from the right, left, and both cameras to create each scan.
We dive more deeply into various 3D scanning principles and methods below.
Laser Triangulation 3D Scanning Technology
As you might guess from the name, laser scanners use triangulation to identify and value the location of data points on the surface of the object being scanned. Most laser triangulation sensors involve a single laser source that projects a laser line onto the object's surface while angled sensing cameras observe that line's shape. A calibration process determines the angle between the laser source and the sensing cameras. The angle between the laser source and the sensing cameras is known, which allows for the calculation of the triangulation process. Each pixel along the length of the laser line is triangulated and valued as the line is swept across the surface of the part. While laser triangulation can produce accurate scans, the technique has challenges with transparent and shiny surfaces.
Photogrammetry 3D scanning technology (photography)
Photogrammetry is an accurate measurement technique often used with optical 3D scanning systems to help with scaling. 3D scanners take images or record surface geometry by taking numerous shots or movements, so if you have a critical project that requires high accuracy, photogrammetry helps align each of the measurements so it is exact.
It works like this: A camera takes photos from numerous perspectives, and then software recognizes the common features in each image and fuses them. Photogrammetry can be performed using either a manual, high-end, handheld digital camera or an integrated camera mounted on the end of a robot in an automated scanning cell.
What are Common Types of 3D Scanning Applications?
Common types of 3D scanning applications range from education, art, and hobbies to medical and industrial uses. The industry that most commonly uses 3D scanning is manufacturing and engineering; therefore, this is where the most advanced applications of 3D scanning exist. Below, we've listed some of the most common types of 3D scanning applications.
3D Scanning for Product Development and Design
3D scanning enables improvements of existing products and provides mechanics and technicians with a new way of seeing how objects work. With the resulting data and the insights it delivers, they might completely recreate a product to make it more efficient. Developing valuable products with efficiency is critical for manufacturers. Designing a few iterations digitally and then previewing their functionality within software prevents errors and frustration before the product goes into production. Cost and time savings are two of the many benefits 3D scanning provides in product development and design.
3D Scanning for 3D Printing, Additive Manufacturing, and Subtractive Manufacturing
Building prototypes is a staple in manufacturing. 3D measurement data from an accurate system can serve as a 3D printer-ready watertight mesh to use to 3D print directly from the data, helping save time that would have been spent in modeling. Additive manufacturing is when layers and pieces are added to the object, while subtractive manufacturing is when layers are taken or cut away to reveal the finished product. While additive manufacturing is helpful with smaller products, subtractive manufacturing is a good choice for large parts. 3D scanning is useful throughout any of these processes.
3D Scanning for Reverse Engineering
Since 3D scanners collect the shape of an item to create a 3D CAD model for reproduction purposes, it enables fast and accurate reverse engineering. In most cases, legacy parts produced several decades ago are only described within two-dimensional drawings, not 3D CAD. 3D scanning fixes this by collecting the dimensions of these legacy parts, resulting in an accurate 3D digital representation. You can then surface this file to create a CAD model. The more precise and high-resolution 3D scanning technology you use, the less time it will take to generate the CAD. That model can then be used to develop new molds and tooling, allowing a manufacturer to produce new parts with the same dimensional characteristics as the original or improved for greater functionality. High-quality 3D scan data helps remove the guesswork in the reverse engineering process and makes it more efficient overall.
3D Scanning for Quality Control
For quality control processes, 3D scanning is the new gold standard for improving products, reducing waste, cutting costs, and gaining a competitive edge. By utilizing the latest 3D scanning technology, manufacturers have access to more accurate data than ever before, and this information streamlines production processes in multiple ways. By identifying problematic parts earlier, manufacturers can save both time and money by reducing development iterations. 3D scan data allows the digital assembly of various components to assess fit and finish before any physical parts get shipped— a significant advantage in modern quality control processes.
The software that typically accompanies 3D scanners automatically creates inspection reports, streamlining the manufacturing process for you and your employees.
3D Scanning for In-Line and Near-Line Production
3D scanning for near-line and inline production produces the most streamlined workflows. The process is automated, which means little to no human intervention is needed. With more availability, employees on the production floor can move around and ensure that everything else in the production process is up to speed. Automated 3D scanning improves quality control, saves time, and reduces bottlenecking.
CFD/FEA Analysis, Adaptive Machining, Digital Assembly, and MES integration
Accurate 3D scanners are a powerful tool for other types of analysis, including Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA), Adaptive Machining, Digital Assembly, and Manufacturing Execution Systems (MES) integration. These types of analysis depend on precise data, and 3D scanners quickly collect the data to power these processes and deliver optimal benefits.
Some manufacturers are involved with the remanufacturing of older parts, which must be brought back to the dimensional characteristics of the original specifications. Each part is distinctly unique in these cases, making it impossible to re-run the original CNC cutter path during the remanufacturing process. Data from an accurate 3D scanner serves as a basis for the CNC cutter path to be "adapted" or morphed into the local geometric shape of the used part. The area of the used part that is to be remanufactured is then welded, adding material that will then be re-machined back to the desired shape using the "adapted" cutter path. This approach would not be possible without the use of 3D scanning technology.
What are Different Types of 3D Scanners?
There are many different types of 3D scanners available, ranging from portable CMMs to laser scanners to blue and white structured light 3D scanners. Below, we've listed a few of the different types of 3D scanners available to help you decide what's best for your project.
Advancements in smartphone technology now allow you to use mobile applications as a 3D scanner. While this method can work well for some hobbyist projects, it doesn't provide the metrology-grade quality and accuracy needed to execute professional-level 3D scanning sessions.
LIDAR (radar technology)
LIDAR uses laser radar technology to detect details on small objects, resulting in high-resolution 3D images.
Laser scanners (handheld, arm, and structured light)
Laser scanners are a popular 3D scanning choice. Available as a handheld scanner or CMM attachment, these can quickly collect surface data but aren't ideal for projects requiring high accuracy because the data they collect is often noisy.
Laser pulse-based 3D scanning technology
Another name you might recognize for this technology is time-of-flight scanning. This method is a bit different in that it doesn't utilize the principle of triangulation. Instead, it uses the speed of light and sensors to measure surface geometry. The laser sends millions of pulses to the object's surface, which is then reflected to the sensor. The timing of the pulses from the laser back to the sensor enables surface data collection in this type of scan. A mirror rotates the laser and sensor hardware, which allows the software to collect 360 degrees worth of data.
Contact-Based 3D Scanning Technology including Touch Probes and CMMs
The technique used in contact-based 3D scanning is different in that it is a more invasive approach. A physical probe must make contact with the object's surface, and a stationary probe is used if the object is moving during scanning. The other method uses a roving probe that moves over the stationary object or a manually operated 3D scanning device like a CMM. The software used in conjunction with the probe will record how and where the probe touches the surface, resulting in its three-dimensional location. Programming a contact-based 3D scanner generally takes significantly more time than other scanning techniques.
Structured Light 3D Scanning Technology
3D scanning devices that use structured light employ the principle of triangulation. A projector is set up with two cameras at angles on either side. The sensing cameras analyze light patterns as they are projected onto the object being scanned. Exact X-Y-Z coordinates are calculated from the data and used to create a precise digital twin of the scanned object.
The projector in a structured light sensor emits a heterodyne "fringe" pattern of light that appears visually similar to Zebra stripes. Those stripes will change in size and direction during the very brief time of data collection. The sensing cameras pay attention to the contrast along the edge of the stripes and value those pixels with X, Y, Z coordinates. The scan data collected with a structured light scanning system is highly organized, smooth, and continuous, containing very little noise (texturing).
Structured light 3D scanning is a popular non-contact measurement method for various applications, including prototyping, research and development, quality assurance, inspections, and reverse engineering. As structured light 3D scanning eliminates the need for physical contact with the object, it makes workflows more efficient and produces faster results with higher accuracy than contact-based scanners like coordinate measuring machines (CMMs).
While that is impressive from a technological standpoint, what about a business perspective? Blue light 3D scanners often win the day there too. Consider that the U.S. Army's Aviation Missile Research, Development, and Engineering Center (AMRDEC) saved up to $100 million due to a project using ATOS 3D scanning.
What are Other Popular 3D Scanners Available?
- ATOS 5 - A structured blue light 3D scanner designed to deliver short measuring times in harsh conditions. Ideal for industrial environments.
- ATOS 5X - A structured blue light 3D scanner ideal for tool, press, and body shops. The ATOS 5X automates the process of scanning the interior and exterior of an entire car body and complete the process in about 30 minutes.
- ATOS Q - An ideal 3D scanner for measuring very small to medium-sized objects. ATOS Q is effective for first article inspections, reverse engineering, shopfloor, lab environments, and other applications.
- GOM CT Scanner - An X-Ray scanner designed for industrial computing tomography use cases. The GOM CT scanner enables the scanning of parts with complex internal structures.
How to Choose the Best 3D Scanning Technology
Choosing the best 3D scanning technology for your specific application requires evaluating certain aspects of the scanner and your project. Certain 3D scanners will work best with some applications, but they might not work well for other projects. To learn how to choose the best 3D scanning technology, consider the following:
While some 3D scanners may cost more, they offer higher accuracy and collect higher data quality. If you are scanning an intricate part or are working with tight tolerances, higher accuracy will be worth the additional cost. Accurate 3D scanners that cost more also have more robust hardware, high-quality optics, stronger software capabilities, and may also include a PC. If you're a hobbyist, these metrology-grade 3D scanners may be more than what you need; however, at the professional level, it's important to remember, "You get what you pay for."
If you're working with applications with tight tolerance requirements, having the ability to verify whether your part is in or out of tolerance is essential, so make sure you're selecting a 3D scanner that can satisfy your tolerance requirements.
Low-quality 3D scanners require more time to collect the same amount of data that a high-quality 3D scanner can, which can cause a bottleneck in manufacturing production. If you need high throughput, make sure to consider the time it takes the scanner to execute a scanning session.
When choosing the best 3D scanner, it's essential to consider where the 3D scanning will need to occur and what will be needed in the environment. For example, if you need an automated solution, you will need more space than when scanning something small with a handheld 3D scanner. Also, consider if you need to travel with the scanner, which would require you to have a portable scanner. If you need to take the scanner outdoors, or in indoor, industrial environments, or anywhere else where lighting could vary, you'll need to consider those aspects as well.
Want to Learn More? Request a Demo!
3D scanners are an investment that can accelerate your processes, increase the accuracy of your designs, and bring success to your projects. Choosing the best 3D scanner for your specific needs is essential to maximize this investment. The best way to select the best 3D scanner for your application is to test different 3D scanning technology. Capture 3D offers virtual and in-person demonstrations of accurate 3D scanning technology used across a range of industries. Requesting a demo is a great way to get face-to-face familiarity with 3D scanning if it feels a bit out of your reach. We'll show you how 3D scanning can improve product design, streamline production lines, and improve quality control. Request a proof of concept to see how the technology works with your project. Contact a Capture 3D team member today to get started now!