DDMC

Jack showed me a cool product called Leap Motion the other day. I took a few minutes to play with it and can definitely see a wide range of applications. What is it? Basically it’s a sensor system that picks up hand gestures to control applications on your computer (or even your computer itself). While not dissimilar in concept to the Primesense family of technologies (e.g. Xbox Kinect and Asus Xtion) the system stands out in as focused primarily on hand gestures and PC applications as opposed to gaming. Many controllable apps are available through their app store with a good portion of them educational in nature such as this anatomy program that let me dissect a skull. The system has an SDK available so programmers can quickly build apps around it without much ground-up work. It certainly presents a lot of potential in the education arena.

This isn’t far out tech or some obscure device you’ll never see in the field either. The unit is $80 and as of this month HP has started shipping laptops with Leap tech built into it with Asus soon to follow. Very Minority Report-ish!

Along with our 3D printers we received 3D scanner and have had a a few opportunities to play with it and learned quite a bit.  At first take our scans weren’t really successful and I was actually a little bit disappointed with the unit (a Makerbot Scanner) but after some practice we got pretty good at it.  You can see the original blue devil and a scanned version of what we made.

How It Works

Basically the object you want to scan is placed on top of a turntable that isn’t all that dissimilar to a real record player.  The unit is USB’ed into a computer an uses bundled scanning software.  A few clicks of the mouse (very limited options) starts the scanning process.  A pair of lasers kick off and on and the turntable begins rotating slowly.  The laser reflected light is picked up by an on board camera and that data is piped back to your host machine that draws you a 3D file.  The process is really simple.

Multi-Scanning

One of the cool things about this scanner is the ability to do multi-scans.  There’s virtual no way to penetrate  every nook and cranny of the object you are examining with the laser beam.  The system is intelligent enough recognize that and allow you to scan the item multiple times from different angles (upside down for example).  This exposes parts of your object that may not have been visible in the first pass.  Upon completing the additional scans (you can do this as many times as you want exposing more detail) the unit will concatenate the scans into a single object, intelligently blending them together.

Sci-Fi vs Realty

Now the sad part, while the scanner does a great job for a $1500 desktop product, the result isn’t perfect.  There are always minor defects.  The hope and dream with a 3D scanner is that you can scan something then immediately print a perfect replica.  That just won’t happen.  The scans, from our experience could be as much as 90% (eyeball estimate) accurate they weren’t perfect.  For example, look at the horn of our Blue Devil rubber ducky, you’ll notice some artifacts.  However, it was a good start if your workflow involved bringing an object into Blender or other 3D software for further refinement.  It may also be good for educational applications where you need to show someone the size and shape of something but don’t necessarily need to replicate something like a gear in a machine, perhaps a skull or other anatomy component.   Another important thing to note, the scan you create will not have any color in it, only the physical shape.

Limitations

There are also some important limitations to note.  The scanner cannot scan certain objects:

• nothing larger than 8 inches high or wide
• nothing heavier than 6lbs
• no extremely light objects (nothing white)
• no extremely dark objects (nothing black)
• nothing shinny (no chrome plating)
• nothing extremely matte (e.g. foam padding)
• nothing translucent (no glass or plastic)
• nothing hairy (no chinchillas)

We’ve had the better part of a week with the 3D printers.  Our printing efforts have been conservative.  Much time has been spent reading documentation and using our printing material smartly (our order of filament hasn’t come in yet).  But we have printed a few things including a model of the Duke Chapel, a steam punk iPhone case, and other cool stuff.

But so far the most interesting thing about the project has been interacting with colleagues.  The printer is setup as a usable display now at ATC.  We run it a few times a day and have even attached a webcam so that people can see the operation.  Response has been great, a lot of people have stopped by and introduced themselves to the technology.

Take a look at our webcam feed or swing by the Media Lab if you have a moment – http://people.duke.edu/~dwb36/3dprint.html