Everything you need to know about 3D scanning for the automotive industry

In this blog, we look at what 3D scanning is and how it works, how automotive manufacturers can use 3D scanning, its advantages and drawbacks, and future trends that are shaping its use in this industry. 

What is 3D scanning? 

3D scanning detects a physical object’s shape and size to a very high degree of accuracy without touching it. The resulting data points are then assembled into a digital 3D model of the object that can be used in any number of applications. 

Different scanning technologies use various methods to accomplish this. Three of the most popular types of 3D scanning include: 

1. Laser scanning

There are two types of laser scanning. 

The first is laser triangulation, which measures the deformation of a laser beam projected onto an object’s surface. There is typically one laser and multiple cameras that record the shape of the line. The angle between the laser and the cameras is pre-determined, so the value of each pixel of the laser as it moves across the surface of the object can be triangulated to produce a high-resolution scan. 

The second type is time of flight, which measures how long it takes for a laser beam to reflect back to a sensor. The speed of the laser is constant, so reflection time can be used to calculate the distance of each part of the object.

Ultimately, both of these measure distance from the laser emitter to the part, so they need to be paired with a position and orientation controlling device like a CMM/PCMM to point the laser at relevant areas of the part to complete the scan. 

2. Structured light scanning

This is similar to laser triangulation, but it measures the deformation of a light pattern projected onto the object. Like laser triangulation, structured light scanning uses one light projector and one or more cameras. The projector displays a pattern across the surface of the object. As the pattern contours over the part, cameras record the changes and derive the surface of the object using triangulation. The light source is typically a blue LED DLP, similar to an A/V projector, and the cameras can record the color of the image being scanned. 

3. Photogrammetry

This approach uses computer vision and algorithms to assemble a 3D model from multiple 2D photographs. Cameras take photos from multiple angles and then software recognizes common points of reference within each image and fuses them together. Photogrammetry can detect colors and textures as well as shape. It cannot detect size unless an appropriate scale tool is present in the images.

3D scanning in the automotive industry enables precise measurements of complex components, improved accuracy and efficiency

How is 3D scanning used in the automotive industry? 

By bridging the gap between the physical and digital worlds, 3D scanning enables automakers to work with high-fidelity digital twins of physical objects within CAD/CAM/CAE environments, allowing for rapid design iteration, measurement automation, enhanced collaboration, and archiving for historical trend analysis. 

Reverse engineering 

3D scanning is a fast method of creating measurements dense enough on a part to resolve even highly complex surfaces and features, which can be useful for reverse engineering or reconstructing an existing part in CAD. Out-of-production parts or parts designed without CAD (or before CAD) can be scanned and the original design intent can be extracted from the data to generate a new file for future manufacturing. Defects in the scanned part can be ignored to preserve part function, design deficiencies corrected to improve function, or other changes can be made if new features, materials or processes are needed. 

Automotive reverse engineering case study: Cummins 

The #28 Cummins Diesel Special is a classic race car that made news at the Indy 500 in 1952. In 2017, the car was invited back to a special race in the UK but its team discovered that the water pump was corroded and would not survive the event. The original pump was unique to the #28 car, so no spare production parts were available. In addition, the car needed to ship out relatively soon, which ruled out traditional sand-casting methods that would take about 10 weeks. 

To solve the problem, Cummins engineers took a 3D scan of the existing water pump housing. To verify the scan data was accurate, they imported the point cloud data into Oqton’s Geomagic Control X inspection and metrology software where they separated and aligned the internal and external geometry of the pump. Then they used Oqton’s Geomagic Design X reverse engineering software to convert the point cloud to a nonparametric solid model to perform CAD fit checks. 

The resulting design was 3D printed with the ProX DMP 320 metal 3D printer from 3D Systems, with assistance from 3rd Dimension Industrial 3D Printing, a high-quality production metal manufacturer specializing in 3D direct metal printing (DMP). The new water pump was 3D printed in only three days and the entire process took five weeks instead of the typical 10.

3D scanning and 3D printing gave the #28 Cummins Diesel Special a new lease of life

Quality control and 3D inspection 

Quality control is the stage at which the manufactured part is inspected to make sure it meets all of the required specifications for proper performance, such as whether or not a cylinder cover will fit the intended engine exactly as expected.  

3D scanning brings a great deal of speed and accuracy to the inspection process, enabling automotive manufacturers to quickly capture a 3D model of a part and compare it to the part’s original design, usually a CAD model. This helps identify any deviations from the design, so parts that do not meet the specification can be pulled from the line. Automotive manufacturers can also use 3D scans to conduct further analysis of parts or assemblies in a digital environment, where high-resolution measurements are more descriptive than manual or CMM measurements.  

Form, dimensions, scale, post-processing mistakes and many other niche analyses can be performed on millions of points very efficiently with modern computers. Additional analysis on tooling can also reveal the root cause of a defect downstream or be used to track tooling wear and notify the user before rework is necessary. Many manufacturers use automated structured light scanning to perform gap-and-flush analysis of vehicle doors and hatches. 

3D printing

3D printing, also known as additive manufacturing, is used in the automotive industry to quickly produce parts as well as make parts that use lighter, stronger plastics instead of more conventional materials. 3D printing typically requires a 3D model, but in some cases a manufacturer may be able to 3D print a part directly from a 3D scan. Alternatively, a 3D scan may require minimal adjustment in a print preparation application to get it ready for final output. Either way, the ability to print a scanned part very rapidly can be used for same-day prototyping, innovative parts for concept vehicles, and manufacturing aids like custom jigs and fixtures.  

QA teams inspecting additively manufactured parts can also overcome the unique challenges of this task using 3D scanning. For example, many additive parts contain highly organic (i.e. topology optimized or anatomical) features that are difficult to measure reliably using traditional tools but are generally simple to scan in 3D and then overlay a reference for statistics and go/no go reporting.  

3D visualization 

Immersive virtual reality experiences are becoming an increasingly important part of the automotive sales and marketing process. 3D scanning the interior and exterior of a vehicle allows manufacturers to quickly create VR-ready 3D models. Virtual tours allow customers to explore a virtual vehicle and experience its look and feel just as if they were in the physical vehicle.  

Vehicle customization 

Many vehicle owners like to customize their vehicles with bespoke parts and accessories that fulfill a wide range of functional and aesthetic purposes. With 3D scanning, aftermarket parts can be made to fit their vehicles with extreme precision. Like a tailored suit, an aftermarket part based on a 3D scan can be designed for a single, specific vehicle, not just a certain make and model. In this way, 3D scanning gives custom parts manufacturers an interesting way to differentiate their offerings.  

Vehicle customization case study: Kindig-It Design 

Kindig-It Design in Salt Lake City, Utah, is a high-end, custom automotive shop that specializes in restoring and modifying classic vehicles. One of the shop’s big challenges is that cars typically have complex surfaces that make measurement difficult. 

To design new parts in CAD that work with an existing vehicle, Kindig-It performs reverse engineering with a FARO ScanArm for 3D scanning and Geomagic Design X software. This enables Kindig-It to make bespoke parts that incorporate intricate shapes, use varying wall thicknesses, and generally fit better. 

Recent examples include redesigned headlights for a 1953 Chevrolet Corvette and a custom air intake for a retrofitted air conditioning system in a 1971 Karmann Ghia. 

Kindig-It performs reverse engineering with a FARO ScanArm and Geomagic Design X software

Design and prototyping

Automotive designers and engineers are often attempting to improve the performance of an existing vehicle part or understand why one isn’t performing as desired. In these cases, 3D scanning can quickly create an accurate, high-resolution 3D model of the part, component, assembly or vehicle as manufactured — as opposed to the original 3D design. With an accurate 3D model of the part, engineers can test out a range of new design ideas in an extremely realistic simulation before actually manufacturing them. Ultimately, this allows design teams to explore more ideas more quickly, make sure their ideas will likely meet performance criteria, and move directly into rapid prototyping/remanufacturing with a higher degree of confidence. 

Replacement parts

This application is a subset of reverse engineering specifically for owners of classic cars, motorcycles and other vehicles for which there are no longer replacement parts available. These vehicles pre-date the digital design era, of course, so there are often no blueprints or even accurate specifications available for replacement parts either. But 3D scanning makes it very easy to create a fully functional 3D model of any part, even one that has not been manufactured in decades. 3D scanning can even be used on broken or severely worn parts. The resulting 3D model can then be improved or evolved in a CAD program until it is ready for manufacture. In addition, 3D scanning can be used on any interfaces with other parts or assemblies to ensure a perfect fit. 

Digital archiving

Many manufacturers use 3D scanning to create a complete digital archive of all existing parts and tools as built. This helps fill in any gaps for parts or tools that were not made from 3D models, those with lost source files, or those without any documentation. This digital archive helps preserve institutional knowledge about all the parts and tools in the manufacturer’s operation.

Marketing

As automotive marketing teams know very well, one of the most expensive parts of the process is staging the vehicle photo shoot. These images drive virtually all marketing content for new vehicles, so very little can move forward until these images of the vehicle are complete. With 3D scanning, manufacturers can simply scan the vehicle and create a realistic 3D rendering that can be used for websites, social media, and digital ads. In addition, these renderings can be enhanced to show various vehicle options without taking the time to photograph all of these options individually. A rendering can be produced off of a scan of a clay model for programs early on in their design process. 

Real-time design development with clay mock-ups 

Clay mock-ups are an important part of the real-time vehicle development process. Typically, after a 2D design has been established, the 3D model is built and then milled out in clay for verification. At this point, more changes are made to the design, often by hand. The challenge for design teams is how to capture new information from the revised clay mock-up and convert it back into digital data. In these instances, 3D scanning provides a relatively fast and easy way to understand the relationship between the clay model and the design criteria and boundaries of the original 3D model. By superimposing the two, design teams can quickly identify discrepancies, edit the 3D model, and send it back to the clay floor on the same day. This allows design teams to iterate more quickly and make decisions with more confidence. 

Benefits of 3D scanning in the automotive industry 

By no means is this list exhaustive, but hopefully one of the applications or challenges listed here resonates with you. Whether you work for an OEM or a small custom shop, automotive designers, manufacturing engineers, R&D teams, quality inspectors and many other stakeholders can expect to benefit in several ways by bringing 3D scanning into their operations: 

• Lower costs. As we have seen in many of these examples, using 3D scanning can streamline multiple steps in the design cycle, leading to faster design, prototyping, testing and manufacturing of vehicle parts. This means faster time to market and lower production costs. 

• Faster design cycle. Before 3D scanning, modifying an existing automotive part often required extremely slow, low-resolution measurement using manual tools like calipers, gages, rulers or CMMs. Then a model or drawing would need to be created by hand to inform the modelmaker or prototyper before the part could be reproduced. The more complex the part, the more measurements were needed, and the more chances for missing or mismeasuring a critical feature. All of this can be done in a few minutes with 3D scanners, which can be up to nine times faster than CMMs and orders of magnitude faster than manual measurement. Again, this is very efficient when creating a design based on an existing part, or a new part that must interface with an existing part, because the 3D scan gives designers a big head start on 3D model creation. In some cases, manufacturers can even go directly from a 3D scan to tool or die milling, which reduces production time even more. 

• Simpler prototyping. Rapid prototyping is an important part of the automotive design process. 3D scanning simplifies the process, enabling design teams to mill a scale model of an idea based on data from a 3D scan, or even 3D print a prototype based on a quick scan. These scans are also very helpful for comparing various iterations of a design idea, which helps reduce the number of cycles to attain a final concept. When the prototype is ready, 3D scanning can also be used to find any flaws.  

• Better quality control. One of the most powerful applications of 3D scanning in automotive is inspection and quality control. 3D scanning enables fast, high-resolution inspection of finished parts to improve the manufacturer’s ability to spot flaws, imperfections and deviations from the intended design. The digital twin created by scanning allows for efficient automation of QA processes and archiving scan data allows analysis of manufacturing trends along one or many production runs.  

• Enhanced product quality. 3D scanners deliver much higher-resolution results than manual tools, with some systems offering up to 10 microns (0.01 mm) accuracy when digitally capturing parts, components or assemblies. 

• Portable convenience. Many of the 3D scanners available to automakers are lightweight and portable by design, so they are easy to use on the factory floor. 

• Minimal training. Many 3D scanners can be used accurately with very little training or experience. In many cases, the total time commitment is only a few hours at most in order to use the scanners correctly and achieve high-resolution results. 

Limitations and challenges 

Like any technology, 3D scanning is not without its limitations and challenges. Automotive manufacturers will need to consider the potential disadvantages of 3D scanning as well as all of the benefits. These include: 

• Cost: The initial capital outlay for 3D scanning can be relatively high, depending on the type of scanner required, along with required accessories and consumables like 3D scanning spray.   Additionally, no 3D scanner is one-size-fits-all. The right hardware for digitizing a small component for QA purposes will likely struggle to scan an entire vehicle, for example, so multiple devices may be needed to address all scanning needs.

• Surface finish: 3D scanners rely on light reflected off the part, so they struggle with shiny, transparent, or dark surfaces that tend to absorb or scatter the laser/fringe pattern emitted. These types of surface finishes are extremely common in automotive applications. In these cases, manufacturers may need to treat the surfaces with a special scanning spray to eliminate transparency temporarily. 

• Data processing: High-resolution 3D scanning can generate files larger than traditional 3D CAD models, which may be difficult to manage with existing IT infrastructure.  

• Integration within existing workflows: Changing any well-established process can be difficult, especially when transitioning from a manual process to a digital one. While 3D scanning does not require a great deal of technical expertise, it will involve some training as well as some growing pains while design teams begin incorporating 3D scans in their workflow. 

The technology of 3D scanning continues to advance. There are several trends that could affect how the automotive industry uses 3D scanning in the near future, including: 

Higher accuracy: New 3D scanners are incorporating algorithmic techniques to achieve even higher precision and deliver more accurate results. 

Automation: Automated 3D scanning systems can perform this process without the need for human operators or technicians, which can bring even more efficiency to quality control inspections. 

Artificial intelligence (AI): The use of AI in 3D scanning can help identify and correct mistakes in 3D scans, leading to faster and more accurate results. 

Cloud systems: Cloud-based 3D scanning solutions help alleviate potential issues with data management and make it easier to share 3D scans and collaborate across locations. This is ideal for automotive manufacturers that rely on engineering teams that do not all work in the same place.  

CT scanning: Once only available at prohibitive prices, this technology is slowly becoming more accessible to a wider range of users. In fact, many 3D scanning manufacturers are selling it today. 

The future of the automotive industry 

Clearly, 3D scanning will continue to be an important technology for automotive manufacturers to understand and incorporate across the design, engineering, production and inspection workflow. Its unique ability to quickly connect the physical and digital worlds is already changing how these processes are performed and should only continue to improve operational efficiency. 

Learn more right now about 3D scanning solutions from Oqton.