How to use the NextEngine 3D Scanner
Please note: this tutorial has been developed for the St Olaf College community. St Olaf IT staff cannot support requests for support outside our community.
It will be a very, very good idea for you to read through this document completely before attempting to use the scanner. There’s a lot to know!
The NextEngine Scanner is a desktop 3D scanner that uses an array of lasers to scan objects at resolutions of 0.005 inches. Because it uses lasers, this is an active data-capture method, as opposed to other 3D modeling techniques we use in the DiSCO, such as with Agisoft Photoscan or the Occipital 3D scanner for iPad. It is not always the quickest method, but if you need to create high-quality 3D models of real-world objects, this is a good tool. One of its uses in industry is for reverse-engineering; take something apart, scan the components, and reassemble them in CAD software like SolidWorks.
With this scanner, you’re able to create almost an exact duplicate of an object and send it directly to the 3D printer for duplication. The scanner has a flash and camera as well, so it collects 2D images to texture the 3D models it generates. It will output files to .stl, .obj, .vmrl, .xyz, and .ply file formats. Our 3D printer takes .stl files very nicely. If you have questions about what 3D capture method is right for your project, please contact the IT Helpdesk to request a consultation.
If you need to use the scanner and this is your first use, this tutorial is part of the check process for you to use the device on your own. You will not be able to use the scanner yourself until you’ve completed this tutorial.
The check process is as follows:
- Read and understand this tutorial
- Attempt to create a viable 3D scan of a test object
- Have a training session with DiSCO staff
- Work with the DiSCO to schedule time to work with the scanner – this time will be added to a Google Calendar to track availability of the scanner
Regardless, you are welcome to ask Instructional Technology/DiSCO staff to scan objects for you. We’ll do this as our time permits on a case-by-case basis. For major scanning jobs, we may ask you to use the IT Project Request Form. Please be aware that scanning can take several hours if you do the scanning yourself, up to a week or longer depending on scan complexity and time available if you ask iTech to do it for you. The NextEngine 3D scanner is not available for checkout – it can only be used in the DiSCO.
Components
- The NextEngine 3D scanner
- The Autopositioner, basically a 360° turntable controlled by the scanner
- The MultiDrive, a two-axis turntable. It will swing ~ +/- 45° in addition to turning an object 360°
- The PartGripper; attaches to the Autodrive and holds down objects.
- ScanStudio Pro software. This is the enhanced software for the scanner, permitting use of the Wide and Extended modes and faster scan speeds.
- Please note that this is a Windows-only application.
General Workflow
It will almost never be the case that you’ll be able to completely capture an object with one scan. Instead, you’ll scan the object multiple times in different axes. Sometimes this process will be automatic, and sometimes you’ll have to reposition the object and then scan it again. The NextEngine supports three kinds of scanning: 360 scans, bracket scans, and single scans. A single scan is pretty self-explanatory; it’s a single pass of the laser over the object and that’s it. A 360° scan, on the other hand, will automatically scan the object through all 360° of travel of the drive (more on this later). A bracket scan will automatically scan the object three times. One directly on the face presented to the scanner, and one time each offset by about ~36°, though you can adjust this setting as well. You can use multiple techniques, scanning the object in a number of different positions to ensure that you’ve collected data over the entire surface of the object. Each group of scans is called a scan family, and you can work with individual scans with a family, or with the entire family at once.
Once you’re done scanning, you’ll then use the ScanStudio software to trim the parts of the scan you don’t need (like the PartGripper and the Autodrive), simplify the scans from the raw data to make them more workable, then use the alignment tools to join all your scan families together into a simple model. The last step you’ll take is to fuse all your individual scans into a single model that you can export into other software.
Getting started
For our examples here, we’ll be using this fellow:
Yes, this is an Iron Man Mr. Potato Head. He goes by the name Tony Starch. We’re using him because scanning him is a bit more difficult than what we’re asking you to scan for this tutorial. All the principles are exactly the same, though, and you’ll be prepared to scan more difficult things on your own once you’re ready. You, on the other hand, will be scanning the below for your scanning check in the DiSCO:
This is a small painted foam tree that’s easy to work with for your first scan. So, as we walk through the scanning process for Tony Starch, we’ll also make reference to the palm tree as we go, with some palm-specific directions with the multidrive later. For now, let’s take a closer look at Tony, shall we?
You can see that he’s covered in talc and little red marks from a chalk marker (that’s included in the standard scanning kit, by the way). We use talc to reduce the reflectivity of objects. Tony’s a bit shiny, so that will reflect the scanning lasers and potentially cause problems. So we use the talc brush included with the scanning kit to give the lasters something to grab onto on the shiny surfaces. In the case of transparent objects, spray painting them a matte white (or using white hairspray so it can be washed off later) is necessary, otherwise the scanning lasers just pass right through the subject.
The marks are for alignment purposes after scanning is complete. As we will see, scan families are comprised of multiple scans themselves, which need to be aligned. And scan families have to be aligned to each other. If this doesn’t make immediate sense, that’s okay, because we’ll walk through the entire process. You probably don’t need to do this on the palm tree, but when you’re scanning a larger object that requires multiple scan families, it’s very helpful to just take the chalk marker and place some Xs or some other marking schema on the object. Below we have Tony’s good side displayed; you can see the Xs on likely spots on his front, and the marks on his arms and body. The marks in the yellow circle are alignment marks on his arms with corresponding marks on his body to ensure that the arms stay in the same position throughout the scanning process. If they move, you probably wouldn’t be able to adjust them properly in the software. Consider the effects of moving parts on objects you scan, and do what you can to either immobilize them, or at least ensure they can be put in the same position during scanning.
Let’s review a bit:
- Use talc or opaque hairspary to reduce the reflectivity of objects or transparency. Scanning lasers need to bounce off something.
- Make sure that any movable parts on an object to be scan are made immobile, or their positions marked so they can be returned to their proper location.
- The scanner kit for the NextEngine includes a talc brush, and red and white chalk markers for reversibly marking up objects. The kit also contains modelling clay to help immobilize objects, or mount them on a drive.
Scanning
The object to be scanned here could just fit on the Autopositioner alone, but as we’ll see later, it might be hard to trim in future steps. And we’ll need it anyway for other scan families. So we’ll use the Autopositioner and the PartGrabber for scanning Tony Starch. For the palm tree, consider using the Multdrive to quickly cover all the necessary scanning angles without having to touch the object.
Here’s the full setup. Note a few things:
- The PartGrabber screws into the Autopositioner on the corners.
- The top of the PartGrabber touches the top of the object and holds it secure.
- Tony is resting on a pair of Post-It pads offset 45° from each other. While not strictly necessary, when doing 360° scans, they give the scanner something to use for automatic alignments. They’re easily trimmed out when scanning is complete.
- The NextEngine is on the left. The Autopositioner cable plugs into the front of the scanner with a old-style RJ-11 (phone) jack. Please note that there’s also an extension for the positioner cable. This really comes in handy for many scanning jobs, since you can get the object farther away from the scanner than the Autopositioner’s cable will allow.
- The NextEngine also requires a USB connection to the Windows machine driving the scanner.
- In the background, Darth Tater and Indiana Spud look on as Tony prepares for scanning. His eyes are immune to the effects of staring into an array of Class-1 lasers. Do not look the laser array yourself.
Assuming everything is ready and properly connected, launch the ScanStudio software. The gear icon at the top of the scanner should light up, the positioner should make some test motions, and the SHAPETOOLS drive should mount. You can click the autoplay window away for the SHAPETOOLS drive. The SHAPETOOLS drive is part of the scanner and contains backup drivers and software. Please do not alter the contents of the drive. ScanStudio should report that “Your Scanner is Ready,” and the scan button to the left should be green:
On the top bar you’ll also see buttons for a number of different tools, greyed out because you don’t have a model loaded yet. We’ll discuss these tools as we walk through the workflow. Go ahead and click the green scan button (an arrow pointing left). Now we get into the good stuff. Here’s the scanning screen. Click on each number for information about what that option does.
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Let’s start scanning Tony. The scanner can’t capture his top and bottom on a single 360° scan. So we can start with a 360° scan with him standing on the PartGripper. Then we’re faced with some choices for how to capture to top and bottom of the object. We could do a second 360° scan with Tony resting on his back on the Autodrive, held in place with some modelling clay, or we could do bracket scans of him on the PartGripper, one for the bottom, one for the top.
For the main 360 scan, we used the following settings:
Positioning: 360°
Divisions: 10
Points/in2: 7K
Target: Dark
Range: Wide. 25″ from feet of object.
This is what we see when the 360° scan is complete. This is actually ten scans, and they’re all automatically aligned by the scanning software for you. While Tony already has some good features on him for this, the Post-It pads he’s resting on help with the alignment by giving it something asymmetrical (the pads really aren’t but they give it something to work with) to help with the alignment.
So, you’ve created a single scan family. Now what? You move the object to a better position for more scanning, that’s what. And then you scan again. The ScanStudio software doesn’t really label it well, but it’s good to think about the filename you created when you started as a project, instead of a file. If you go to the directory where the data is saved, you’ll see that your file is really a folder with your filename with many files stored within. All you need to do to continue is simply reposition the object and scan again. The data will go to the same filename, and when complete, will appear as another scan family. The software will initially support up to 5 scan families in a project, but you can use as many as you need to cover your object. It’ll just add more as you need them.
It is always a good idea to save your project periodically, such as after each scanning or editing operation. The software does not autosave.
So next, we’ve done two more scans of Tony: bracket scans of the head and feet. So with the 360° scan, and scans of the top and bottom of the object , we’ve pretty much covered the total surface of Tony. These scans are done simply by turning Tony onto his back and pointing his head to the scanner, with a bracket scan, and then doing the same thing with his feet.
In the pictures above, you can see how these bracket scans turned out. The scanner only picks up the three views it sees on each bracket scan run, so the scan of the head captures a bit of the sides, but not the bottom. And vice versa for the feet– you capture a bit of the sites but not the top.
Our next challenge will be to trim all these scans up and align them. If you’re working with the palm tree, you’ll still have to do this, but your job will be a bit easier, since you’ll be using a simpler object. First., let’s go into scan families a bit. They’re listed by letter on the bottom of your screen. You can make one active by clicking on it. Once you do, it’ll get a white highlight around it. You can then trim that family, or do other work on it, basically grouping all the component scans into a simple file– not worrying about the fact that you’re really working on multiple scans. But! If you double-click a scan family, it expands and shows you all the component scans. This is very handy if you need to do alignments within a scan family, and sometimes you’re going to need to. This way you can reach in and make that one tiny edit you need to, without disturbing anything else. Right-click on the scan family to bring up a menu– here’s where you can delete a scan family if it’s bad for whatever reason. You’re also able to attach scans to another scan family through this menu.
Since you can easily delete a scan family that’s not up to par, it’s a good idea to check them visually before moving on.
How to rotate and move the model on the screen
Click anywhere in the main model area on the screen with the mouse to move the model. While holding down the left mouse button, moving the mouse up and down rotates the model in the Y axis, while moving it left and right rotates the model on the X axis. Holding down right mouse button and moving the mouse up and down (on the Y axis), will zoom in or out on the model. The mouse wheel will do the same thing.
Trimming
Once scanned, your model will inevitably have things, like the base and probably the PartGrabber, that don’t need to be in the final model. You’ll need to trim those out. Along the top toolbar is an icon for Trim (it has a pair of scissors), go ahead and click it. The first thing it will do is save a backup file of your model. This is a lovely thing, since you will almost certainly use a backup from time to time. Once done, you’ll have a selection of trimming tools:
The pointer arrow doesn’t work for trimming, it’s just the tool you’ll use when you need to move the model. The circle and the square are the most useful (and may remind you of Photoshop selection tools). You can also define a rectangle, or create a polygon to select points.
Use the tools to highlight the points to be trimmed. Highlighted points will appear in red. It’s a good idea to highlight areas in sections and hit the trim button. Given that we’re often capturing thousands (or tens of thousands) of points per inch, when you run the tool over points you’re selecting, the computer has to decide if each point is in our out of the selection and flag it accordingly. This consumes more compute and memory than you might think. It’s also a good idea to take care of the easy-to-access parts to be trimmed, and then zoom in and carefully remove the remaining areas. You can see this above, the majority of the PartGrabber and the base have been selected, but a small part of the grabber where is touches the head has been left behind, and the same for the base around the feet. It winds up being quicker and more accurate to trim in stages.
Note: if something’s really distorted, consider just trimming it out if you’ve got better coverage from another scan. It’s better to just delete the bad stuff than it is to try to fix it. If it’s really bad, just re-scan.
If you do make a mistake, though, you can use the De/Select tools. The + means add to the selection. Your chosen selection brush will be red. The – means remove from selection. Your chosen brush will be blue, and anything you selection with it will be removed from the trim selection, lose the red highlighting, and return to whatever color it originally was. Don’t be afraid to zoom in really closely and remove excess points. Don’t know if something should be trimmed? Switch back to the pointer, and move the model. Changing the perspective often makes it clear what needs to go. Don’t forget to switch to the pointer and move your perspective around to check that you have everything right before you hit Trim.
Trim all of your scan families before moving on to alignment. Toggle out of Trim mode and back in after every scan family you trim to create a good backup. You’ll have less data to worry about, faster processing times, and you’ll make aligning everything later easier.
Aligning Scan Families
Here’s the most important step, and doing a good job here is one of the best things you can do to ensure that you get a good outcome. Go back to the main screen if you’re not already and click the Align button. The Alignment window will open.
Unlike Trim, the software won’t create a backup for you. It doesn’t need to, since you’re not actually modifying the files themselves, just how each scan is oriented with respect to the others. If you make a serious mistake, you can start over by going to Align > Remove All Align Info. In the picture above, you’ll see that the display has split into two. What you’re doing is seeing two different scan families. On the bottom of the screen, which two you’re looking at are highlighted with white. The family in green appears on the left. If you’ve prepped your object well, aligning should be fairly straightforward. On the upper-right corner of each screen, you’ll see three colored dots. Find a unique, identifiable spot on both models, then drag a dot to that spot, and the same colored dot to the identical spot on the other scan family.
Once you’ve done this, both screens will zoom in on the dots you’ve placed and allow you to refine their positioning. Above, we’ve got the red dots placed on a red chalk X from two different families. Liberally marking your object with Xs and other identifying marks makes aligning your scan families much, much easier. Do this for all three pins. Once you’ve done that, the software will give you three more. You can do more if you want, if you happen to have excellent locations for them, but more than three isn’t really necessary. When you’re satisfied with your pin positioning, click the Attach Scans button that appears in the yellow information box after you’ve placed three pins. Processing may take some time. Once complete, it’ll report your alignment precision, usually somewhere between 0.025″ and 0.001″ inches.
What’s next?
This is a good time to check the entire model over, checking the alignments, and trimming out anything else you missed (which is more likely than you might think). At this point, the model is still comprised of multiple scans, so it’s possible for you to go back and edit pins, calculate alignments, and generally tweak things. But if things look the way you want them to, it’s fine to not fix what isn’t broken.
Simplification
Before you fuse, if you’re doing a large object, consider doing some simplification. Were we to export Tony Starch’s fused model right now, the .stl file alone would would be about 600MB. That’s just too much data. You can do these simplification routines while you’re scanning, but this way you can see everything in the full dataset before you make simplification decisions. There are a number of ways to simplify, cleanup and edit scans or models as you go. Before you fuse, consider using Re-Generate Scans. Find it in Fuse > Re-Generate Scan(s) along the main menu bar. The big reason why we recommend this tool is that it does not lose any of your original data. Since here you’re working with a completed and aligned model, you know what the data look like, and are in a better position to judge how well simplification went:
In the Re-gen Settings, you can leave Smoothing and hole-filling at the defaults, unless you feel that you should alter them. However, higher simplification values will result in fewer points in the model. A simplification level of 2 will result in 1/4 of the original data, a level of 3 will yield only 1/9 of the original data, and so on. The original data itself is unharmed, so this is a reversible process. You can increase or decrease simplification with Re-generate Scan(s) at any time without losing data. The only caveat is that you must do so before you fuse. After fusing, you can use the simplify tools under Polish > Simplify (reduce triangles), but you’ll have better post-fuse options if you export after fusing and bring your model into MeshLab, where you’ll have a variety of editing and well-documented simplification options (though it helps if you know some computational geometry; MeshLab can get intense). If you have questions, please feel free to consult with iTech staff.
Fusing scan families
So. You’ve done all the scans. They’ve been trimmed. They’re all lined up. It’s time to merge all these guys into a single scan. We do this in the Fuse window. Make sure you’ve got your work saved (doing a File > Save As… won’t go amiss here, call it backup_before_fuse, or something). Then, click the Fuze button on the toolbar. The toolbar will shift to only the Fuze button (don’t press it yet), and Settings to the left of the Fuse button. Press the Settings button:
Basically you can use the defaults here. However, you’ll want to ensure that the Create Watertight Model (Fill All Holes) option is checked. This is essential for a good finished model for export. For very large models, you’ll want to consult with iTech staff on how to best simplify your models before export– you’ll note that Tony Starch isn’t really all that big, but is made from over two million points and almost four million triangles. The main file alone is over 500MB; the entire project to create this model is almost 6GB. Sometimes simplification is the only way to successfully complete a project– even if we had the storage to save all these points (and we do!) the processing times can get unwieldy for not a lot of benefit in the end. Click Apply when you’re done with the settings, but don’t hesitate to look at the More Info button and learn what’s going on behind the scenes.
Next, assuming you’ve created a backup and your fuse settings are correct, go ahead and hit the Fuse button. It’ll save a backup file, and fuze all your scans into a single model. The fused scan will appear as a new scan family.
Export your work
This one’s easy. Simply press the Output button at the top of the screen, and your preferred format. Our Stratasys Mojo printer takes .stl files, so if that’s your final destination, export to .stl.
Make sure that you save Finished scans only, and that you save as a single file. You are done!
… unless, of course, you’re doing your scanner check procedure, then you have to scan that foam tree– which is a markedly easier process, but now that you’d read through all this, hopefully it’ll make some sense and you’ll have a easy time of it. if you need to use the Multidrive with the scanner; instructions are below.
NextEngine Scanner Check Process: Scanning the palm tree with the Multidrive
This is going to work just like the process described for the Tony Starch object, with one difference. We’ll use the Multidrive. Start by asking for help, and connecting the Multidrive to the scanner, if it’s not hooked up already. DO NOT CONNECT THE MULTIDRIVE TO THE SCANNER ON YOUR OWN WITHOUT SUPERVISION FROM INSTRUCTIONAL TECHNOLOGY STAFF.
Time Requirements
Scanning the tree doesn’t take all that much time, but it still takes a non-trivial amount of time. Expect to spend about 3-4 hours in total on the scan. Some of that time the scanner will be scanning the object and you can be elsewhere (in class, studying, napping, whatever). The scanner’s going to do its thing without your supervision while it’s on, and watching lasers go over your objects is only cool for so long. But you’ll need to be present and working with the software when it’s not actively scanning.
Connecting the Multidrive
- Unplug the scanner, both USB and power.
- Unplug the Autodrive from the front. This uses an RJ-11 (telephone) plug, so you’ll need to release it. Don’t just pull on it and expect it to come out.
- Turn the scanner over. The multidrive plate screws into the bottom of the scanner.
- The holding screw for the multidrive is stored in its hole on the bottom of the scanner when not in use. It uses a 5/32″ Allen wrench (one is stored with the scanner supplies). Unscrew it, keep it handy.
- This is the hard part. The aluminum arm of the multidrive is fragile, and the multidrive isn’t as tall as the scanner. The arm can be easily be bent or damaged if you’re not careful, or you could wrench the turntables. It’s a good idea to do this on something a bit padded to protect tables and the finish on the scanner components.
- Turn the multidrive over, so the arm will meet the scanner.
- Lean the scanner in a bit towards the drive, and line the hole in the multidrive arm up to the screw hole in the bottom of the scanner. It will only fit one way.
- Start the screw and tighten until snug with the Allen wrench. You’ll want to remove it later, and it’s just to keep everything snug, so there’s no need to make it really tight.
- Refer to the pictures below.
- Once you’ve got the scanner and Multidrive connected, carefully turn the assembly back over to rest on the table, taking great care to not put pressure on the turntable assembly– it moves easily and you can stress the gears inside (this is experience).
- Plug the control cable from the Multidrive into the front of the scanner. You’re ready to go!
- DO NOT PLACE OBJECTS WEIGHING MORE THAN ONE POUND ON THE MULTIDRIVE.
Scanning the Palm Tree: Object Prep
The NextEngine scanner comes with a number of bases and ways to attach objects to the drive baseplates. For the palm tree use the flat plate. There will probably have some adhesive squares on it to assist with stability; ask a member of staff if they’re not present and the tree isn’t as stable as you’d like. There is also a pin insert that will work too, but the plate is easier to stick the tree to and it seems to move less as the Multidrive tilts, making for a better scan.
If there aren’t any marker arrows on the tree, free to free to add some. Likewise if the tree isn’t talc-dusted, consider trying that too to increase contrast for the lasers.
Scanning the Palm Tree: Settings
By now these settings should at least look a bit familiar. If they don’t, scroll back up to the setup section for the Tony Starch example. You should see a few new things, though:
- Multidrive is your only option for scan family, since it’s connected to the device.
- The dots on the menu row for each scan family are actually radio buttons. A scan family with the button toggled off won’t run when the Scan button is pressed, even if you have it set up.
- Start and Tilt options have been added for positioning.
- Start refers to the location on a circle in degrees where the scanning begins.
- Tilt refers to the degrees of tilt of the turntable. The turntable can tilt +/- 45°
- The Range is automatically set to Macro. You cannot change this, since the scanner will default to this the moment it knows the Multidrive is attached.
You’ll also note that the tree has been dusted a bit, and some alignment marks added. If you get a clean tree, consider adding them, but it’s quite possible to get a good scan of a clean tree.
Scanning the Palm Tree: For the Win
How you set the scan families up is completely up to you. However, simply doing a single 360° won’t work on its own because you won’t be able to capture the top of the tree, and you’ll miss a bit of the base because of how the object fits within the frame of what the scanner sees. Therefore we suggest three different scan families, though, again, how you set this up is wholly up to you. In the end, you need to present us with a completed scan of the tree.
Suggested settings for Palm Tree scan | |||
Scan Family | |||
A | B | C | |
Divisions | 16 | 16 | 16 |
Start | -90 | -90 | 20 |
Tilt | 0 | -15 | +15 |
Points/in2 | 16K | 7K | 16K |
Target | Dark | Dark | Dark |
Remember the workflow. Once the scans are complete, you’ll need to trim the scan families. You might want to check the alignment and adjust as necessary as well. If you’ve done this right and the tree hasn’t moved while scanning, this should be pretty minimal. Do anything else necessary and fuse the scans, then export your model as an .stl file, and show it to a member of the iTech staff— please note that student workers in the DiSCO can’t clear you for use of the scanner. If you successfully create a good scan of the tree, fill out the check form in the presence of an Instructional technology staff member.
Congrats! You’re now allowed to schedule time on the 3D scanner, and scan whatever your heart desires. Within reason, of course. Have fun, and make cool stuff!