3D scanning and printing

This week's assignment:
   * 3D scan an object
      - extra credit: make the scanner
   * design and 3D print an object (small, few cm)
      - extra credit: edit and print an object that you scanned

Commercial 3D-scanner
This week I skipped class with Harris. Instead of going to class, we went to a fair called 'rapidpro', where many suppliers were present dealing with rapid prototyping products and techniques. This was precisely the subject that includes all our lessons.
I had taken a piece of wood carving, a lion head, with me from home. I wanted it to be scanned by as many different scanners in order to compare results in resolution and ease of use. I was wondering if one of these scanners can be used for reproductive purposes and some restoration purposes. Ultimately the piece was scanned by two scanners the Z-snapper and MMDX 50 3D Scanner from Nikon.

Tools, materials and techniques
- zsnapper 3D scanner
- MMDX 50 3D scanner Nikon
- meshlab
- Rhino
- Z-corps 3D printer

Findings MMDX 50 scanner Nikon
The 3D scanner Nikon MMDX 50 was a handheld scanner that you have to move around the object, like as if you are spraying the object. On the screen you'll see realtime results in a point cloud, so you know exactly where you left off.
-This scanner is very easy to use. With an inventive adaptation you could possibly also scan bottom of the object.
- The files are not very large.
- Result is also dependent on how long and how exactly you've scanned. I had not much influence on that, since I didn't operate the scanner.
Findings 3D zcapper
Coded targets on the object plate were used to determine the position of the scanner and the object. These coded targets consist round stickers with a dot in the center surrounded by a circle, that was broken in different places on each sticker.
- In this set-up the scanner was mounted on a tripod while the object turned. Although it was also a handheld scanner.

Results
meshlab

zsnapper  nikon
Z-snapper                                            Nikon

3D scanning by structured light with three-phase method

Tools, materials and techniques
a pico-projector
camera
object: wooden carved lionhead
processing

Results
1 2 3
meshlab

1 2 3

meshlab2

Findings
The result is not very good. In first place, we thought the position of the camera and Pico projector was not right. We have set up the Pico projector  so that the projection was as a square as it could be and put the camera in different angles in comparison to the object and exactly above the projector. Unfortunately without better results.

Then we decided to do calibration of the projector and the camera properly by using the technique described in this article. We found a camera calibration program using OpenCV library on Internet, compiled and tested it successfuly with a set of chessboard pictures. And we planned to translate this program to Python (OpenCV used in this program has bindings for Python), because it would be easier for us to modify by adding projector calibration functionality.
So far this project due to time restrain

Printing
I took the file from one of the scans processed with one of the commercial scanners. Then closed some wholes in meshlab and then made it watertide and resized it to a smaller object using Rhino. This STL file I sent to Fablab Barcelona. They have the object printed with the Z-Z510 corps. The results of all printed objects from the Fab-students will be seen in Lima on Fab7.