NextEngine 3D Scanner (Cadalyst Labs Review)1 May, 2008 By: IDSA ,Mike Hudspeth
Reverse-engineering tool is affordable, versatile, and easy to use.
There are many times when you have a part in front of you that you need to either incorporate into a design or design something around. There are no drawings for the part. You just have one in your hand. What do you do? You can model the part by measuring it all around, but you stand to introduce error. (Be honest, it will almost always happen.) But one way you can capture that part is to do a 3D scan. Costs too much, you say? Not anymore. The tools are getting more affordable, and with the NextEngine 3D scanner they just might be in your budget range.
The NextEngine 3D scanner uses a laser to capture the surface details of your model (figure 1). It can do a complete 360° scan. It comes with a turntable that rotates your object and a gripper that holds it steady. Setup is very simple; you just pull everything out of the box and plug it in. You have to load the software before you hook the scanner to your computer. There is an amazing scarcity of initial instruction — just a graphic pasted on the inside of the box top. I guess NextEngine assumes it's so falling-off-a-log simple you can't help but figure it out. One thing of special note: You must have a high-speed USB 2.0 port. The older ones won't connect to the scanner. In addition, NextEngine says you need 2 GB of RAM.
There are a lot of settings you can monkey with to get just the right scan for what you want. The Bracket scan does three scans (36° each). The Single scan does not turn your object but merely scans what it sees. The Macro setting has a higher accuracy (±.005), but it only scans an area as large as 5" x 4". The Wide setting has a lower resolution (±.016) but will scan an area as large as 13" x 10". Each standard scan takes roughly a minute and a half. The quick scan will take 30 seconds. The finest scan will take two and a half minutes. As far as surface finish is concerned, a flat white finish gives the best results. If you have an object to scan that has too many shiny spots, a powder pen comes with the unit. It will take some of the shine off those problem areas in your scan.
When you have your object secured and ready to scan, the scanner will take a 2D photo and save it to a JPEG file. That's so the final result will really look like the object. Next, multiple stripes of lasers begin to scan: two, three, or all four depending on your settings. You can set the turntable to rotate the object for each scan.
NextEngine 3D Scanner
The scanner will capture 60,000 points per second. That's a lot of data! It's what it does next that is really interesting.
While you are scanning, you may notice some errant glitches in your data. Say, for instance, you capture the scanner's gripper or the turntable. What can you do? You can trim your scans, just like in a paint program, while you're still scanning. Just select what you don't want and delete it (figure 2). It's that simple. It's nice that you don't have to wait until the unit is done scanning to work on previous scans.
When the scanning is done, you are left with several 3D scans that have major overlapping areas. What you really want is one unified object. NextEngine has got you covered. You can align the scans and sew them all together. You can let Next-Engine's software try to align them automatically, but you can also go manual! It works much like the good old light table. You overlay what you want to see and align everything until it matches what you want. Then you identify three points (with cute little virtual push pins) in two views and the software can do the rest (figure 3). You could try to eliminate the overlaps as you scan, but you'll get better results by waiting to eliminate the overlaps until the end.
As you might expect, there is always going to be some amount of misalignment. The software is ready for that. It will give the scans a virtual wiggle to get a better fit. Once everything is matched, the extraneous, repeated, overlapping points are eliminated and everything is fused together (figure 4).
For those who want to bring their scans directly into SolidWorks, Next-Engine offers RapidWorks. This software works a lot like Geomagic. It is basically a licensed version of RapidForm ($20,000) that saves to SolidWorks — hence the name. You take the scan and find its edges or make cross-sections of its volume. You go through each portion of the model and create sketches from which you can extrude or cut things. What you end up with are actual parametric features.
I really like The NextEngine 3D scanner. I think it will probably have a great effect in the engineering, education, and art markets. Think about it: An archeologist could scan a relic and make it available on the Internet for all to see. And artists who are constantly pumping out one-of-a-kind pieces of art could use the NextEngine scanner not only to show off their work but to reproduce it for sales as well. (So much for the starving artist.)
The basic unit goes for $2,495 and comes with the core software that lets you output to STL, OBJ, VRML, U3D, and other formats. The Pro software ($995) creates non-uniform rational B-spline (NURBS) and spline output for import into most CAD programs. The RapidWorks program ($2,495) generates actual parametric SolidWorks models (or saves to IGES, STEP, or mesh).
For more information or to contact NextEngine, visit the company's Web site at www.nextengine.com. (There is a great little YouTube video that takes you through the whole scanning process there. Check it out!) Highly Recommended.
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