5 Questions on 3D Scanning

(Image courtesy of Artec 3D.)

Despite its rapid progression, 3D scanning is still a relatively new technology when it comes to quality assurance in manufacturing. Even if you already know the basics of how 3D scanning works, a new perspective from a subject matter expert can provide a welcome refresher or even reveal novel insights into the technology.

ENGINEERING.com asked Rus Emerick from Laser Design, an official Artec 3D reseller, five questions about 3D scanners. Some of his answers may surprise you.

How has 3D scanning impacted quality assurance in manufacturing?

Traditional quality assurance was built upon trying to capture a part definition on a 2D drawing’s dimensions, both linear as well as—later—GD&T. These dimensions were measured individually on each part, which was time-consuming and subject to the skill of a CMM [coordinate measuring machine] operator, involving fixturing, programming and machine runtime.

(Image courtesy of Artec 3D.)

Using 3D imaging, all the geometry of the part is captured. Not only can the linear dimensions be extracted automatically—PMI embedded in the CAD model—but all of the areas “between” the drawing’s 2D locations are available for measurement as well—all from a single scan. The volume of data to “assure” the quality of the part is so much more thorough, resulting in a better definition of the entire part in less than 25 percent of the time.

Quality assurance has always been the bottleneck in the product development process. The use of 3D imaging has eliminated this issue, greatly reducing time-to-market by typically 60-70 percent.

What are the biggest misconceptions regarding 3D scanning for quality assurance?

To the uninitiated, there are always questions as to the accuracy of the scan data. Once a Gage R&R is conducted on the scanning system, these misconceptions tend to melt away. White light scanners are accurate to approximately 0.00075 in (19 microns), laser scanners are accurate to approximately 0.0005 in (12 microns), CT scanners are accurate to approximately 0.0001 in (3 microns).

(Image courtesy of Artec 3D.)

Scanners can be expensive, but when compared to the cost of quality and the value of data that is useful for all functions—design, engineering, manufacturing and quality—the system costs are very reasonable, as all the data can be extracted from a single scan, depending of what the function needs to know about the scanned part.

What are the most common mistakes you see customers making when using 3D scanning?

Most customers assume all scanning is equal, without matching the scan technology to the measurement or data that they expect to receive. Likewise, from a cost viewpoint, as resolution becomes finer the cost increases.

However, depending on what you are scanning, you do not always need the very highest resolution. For example, you would not need a CT system to scan a 2-in x 4-in wooden stud.

The customer should base his or her decision on resolving the smallest feature to be considered to assure the quality of the part.

What advice would you offer to a quality professional purchasing their first 3D scanner?

I suggest that the customer submit a typical part to be scanned to the supplier of 3D imaging equipment being evaluated, using the features and part definition declared in the inspection plan.

Never rely solely on specification sheets.

Professional scanning companies will always recommend the best scanner for the required measurement, not necessarily the most expensive.

What’s the most interesting or exciting 3D scanning application that you’ve seen?

We had the opportunity to scan a live lobster for a research team on the east coast of the U.S. It was very interesting to work with a live animal. We needed to capture an accurate scan, without causing any harm.

(Image courtesy of Artec 3D.)

We used an Artec Space Spider, which allowed for some natural movement by the lobster, but still rendered the detail needed by the research team. For another animal project, I had the task of measuring how big a salamander’s tooth was using CT. I didn’t even know they had teeth!

I also had the privilege of scanning a heart pump less than the diameter of a pencil, which can replace the typical “heart-lung machine.”

Seeing the progress underway in the medical industry never ceases to amaze me.