Many of you have been asking for a laser scanner that can turn your CupCake CNC into a 3D copier. Thingiverse user tc_fea (aka my dad) is hard at work making that a reality. Using Visual Basic, ANSYS and a lot of math, tc_fea has gone from scan to print. Leave a comment if you’d like to see the source code and we’ll be sure to post it online.
Required Equipment
Chessboard
Laser-line level
Web camera
Windows PC with Visual Basic
Step 1 – Scan the Object
First, tc_fea puts the scan object in front of a known, calibrated background – in this case an antique chessboard. He manually moves the laser line level incrementally across the image, taking a picture after each move.
Step 2 – Compute the Point Cloud
Tc_fea feeds the multiple scan images into his Visual Basic software for processing. The software does the following:
Subtracts each scan image from a baseline image (with no laser line). This produces a very high contrast scan line.
Subtracts the RGB component colors separately from the scan line, pixel-by-pixel (using Bresenham’s Algorithm). This allows a color scan.
Applies a threshold filter to isolate the scan line from the background.
Assemble the scan lines into a point cloud by performing a number of image transformation routines based on OpenCV methods
Renders an image of the 3D point cloud in color
Step 3 – Mesh and Create an STL file in ANSYS
Next, tc_fea meshes his point cloud in ANSYS, a analysis package used, among other things, to analyze fighter jets and certify nuclear reactors. Overkill? Absolutely. Expensive? You bet. Fortunately, tc_fea is using an affordable demo version called ANSYS ED, which has many of the features in the full version, but limits the number of nodes and elements. Tc_fea’s program kicks out a pretty good point cloud, so you could probably accomplish the same thing in MeshLab or Blender (both free).
Step 4 – Print!
Finally, tc_fea prints the scanned part using his CupCake CNC running ReplicatorG! Homemade scan to print for less than $100!
Awesome. The amazing Unfold has come up with a contraption that lets folks sculpt virtual pottery! Very cool!
For L’Artisan Electronique, Unfold created -aside from the ceramic printer- a virtual pottery wheel in collaboration with Tim Knapen. This pottery wheel gives visitors a chance to ‘turn’ their own forms. Every time a visitor presses “Save” on the arcade buttons, the creation is saved to disk and displayed on the wall. At regular intervals, a selection of these designs is printed in clay using a modified REPRAP machine and exhibited in the space.
The virtual pottery interface uses openFrameworks with openCV to track visitors’ hand positions in the air. There are two parts to the scan, one being the green laser projecting lines onto the hand and camera recording the deformations to the line created by the hand. The curvature recorded is used as a cylinder deformer.
We live in the future. The super customization side of 3D printing can change people’s lives.
For Summit, the peak of what’s possible with 3D printing may be found in the medical and prosthetic fields. Because of 3D scanners, he said, it’s possible to craft prosthetics that almost perfectly mold to a wearer’s body, unlike more standard models from the past.
Personally, he works on making 3D printouts of legs for those who have lost their own, both in plastic and metal. Summit’s 3D-printed legs are even dishwasher-safe, he said, and curbside-recyclable artifacts of the materials that can be used in the production of such items.
Because the models can be shaped based on patients’ remaining legs, Summit suggested that they are more attractive than what has been possible in the past. Indeed, he said those who have sported early models have reported regular admiring comments from kids and even girlfriends.
“For the first time in his life [as an amputee], kids on the street are jealous of him,” Summit said of one customer. “No one’s ever been jealous of him.”
And to Summit, hearing that those who have used his prosthetics find them to be a pleasant part of their lives–insofar as such an item can be pleasant–is a big part of why he’s set out to transform an industry that has been helping people for years, but with little regard to their specific individual needs.
“If the first thing you see in the morning is this by your bed,” Summit said of one of his more attractive prosthetic models, “you’re pretty psyched. That’s my goal.”
Hat tip to Greg Marra who pointed this article out to us!
I found this about a year ago and then lost the link before I could blog about it. Thankfully, the gentleman Douglas Repetto sent a link today to the Thingiverse group and now I can share this project’s beauty with you!
It’s a glorious machine that runs on very old-skool early reprap technology. Zach designed and shipped those boards two years ago. If I was an art collector or MOMA, I would buy this. It’s awesome!
This system uses lasers to scan an onion plant from one of three angles. As the plant is scanned a fuse deposition modeler in real-time creates a plastic model based on the information collected. The device repeats this process every twenty-four hours scanning from a different angle. After a new model is produced the system advances a conveyor approximately 17 inches so the cycle can repeat. The result is a series of models illustrating the growth of the plant from varying angles.
If you’re interested in laser scanning you’re going to need a laser level. Recently I got some laser levels from DealExtreme. It’s a bit touch and go, I got 4 lasers and 2 of them have good lines, so if you get some, get a few!
If you’ve got a hookup on galvanometers, drop a note in the comments!
I’ve been wanting to mess around with David Scanner for a while but it only runs on windows and I’m hardly ever around a Windows machine. Since it’s the weekend, I was able to hijack Marisol’s computer and give it a go.
I went to the corner store and bought a model of a knight’s helmet to scan. The helmet was silver and we just happen to have spray chalk, so I sprayed it down with the chalk and that made it nice and matt and perfect for scanning. Reflective things are bad for scanning because they reflect the laser line. Spray chalk is great, but I had to do some touch ups because it rubs off very easily.
I acquired a laser level and a webcam and then began the setup. There is some preparation involved. You have to assemble a model of a backdrop and then get all the pieces in place and go through a set up calibration process. Once I did all that, which took a few hours of reading the manual and getting everything adjusted, I swept the laser line over the model and it makes a point cloud.
I saved an stl file and even though I was using a super high resolution webcam (720×1240) it downconverted it to 320×240 because I don’t have a license. I made three different scans, one from the front and one from each side and then spent about 2 hours learning how to mesh them together in the David Scanner software only to find out when I went to save that this is an option that only works if you have a license. It’s clear in the documentation that this isn’t a free feature, but I wish I had a heads up before I spent all the time meshing the stls together.
In steps Meshlab to the rescue. It’s an open source program that does joins meshes! With Meshlab I was able to take my low resolution stl files and put them together and then do a poisson thing that brings them all together into one mesh. I ended up with an stl model that looked like a very low resolution copy of the knights helmet.
At some point in the very near future, 3D scanning is going to be huge. How do I know? Check out these scans of siamese twin skeletons that have been 3D printed! I can’t wait until people start uploading their medical files to Thingiverse for sharing and printing on MakerBots! Read more!
Argon, published an instructable with instructions on how to make a 3D scanner. 3D scanning is cool. Using a 3D scanner you can bypass the digital designing part of 3D printing and goes straight to object replication.
Check out this video and accompanying instructable for more info on this particular 3D scanner. As we come across more 3D scanning possibilities, we’ll do our best to keep you posted!
