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

1.- 3D SCAN AN OBJECT

For the first part of the assignment I have used three techniques
a.- 123D Catch (software)
b.- Vi3dim (software)
c.- Modela scanner (hardware)

a.- 123D Catch (software)
I used 123D Catch to create a model of a porcelain sheep.

123D Catch is a free program and with it you can obtain a 3d model by taking multiple pictures around an object.

Here are some tips on how to select objects and how plan out your catch so that you obtain goods results:

    -When choosing objects to scan, avoid reflective surfaces, objects with glare and mirrored or transparent surfaces.

    -When the background consists of different elements you have better results, avoid a white background. The program takes references of the things that are around.

    -Photographs should capture all sides of the target object, both all the way around, and top and bottom.

    -A good approach is to take 20 photographs of the object all the way around then move up (pointing the camera down at the object) and take some more, and then move down (pointing the camera up at the object).

    -A smaller platform for the object helps capture more details from below.

    -Consider using some marking system when your object lacks discernible features or is highly symmetrical.

    -The object should not be moved at all during capture, and lighting should remain consistent. Once the object is in place, you should move around it

    -The object should take up most of the frame.

    -While it is not absolutely necessary to maintain the same distance from the object all the way around, it does help the program if distances are consistent.

    -Consistent diffuse lighting all around the object works best.

With all that in mind I decided to make a platform to take the photographs.

I used some PVC pipe and a Gorilla Pod stand for the Iphone. 

The height of the camera can be regulated and rotate it around the object.

It is a little unstable but with some patience you can take the photographs, I am working in v2.

I did 35 photographs, the goal was capture as many different angles of the object as possible.

The next steps are:

- Open 123D Catch and click Create a New Capture.

- Log into your Autodesk account (or create one).

- Upload the photos from your computer and submit them for processing.

- After you upload your photos, click Create Project.

- Fill out the form completely and click Email Me.

- Wait until Autodesk send you an email when your scan is ready.

During this process some holes appeared on the object. Result after generating the mesh.

After generating the mesh you must export your scan as OBJ file (File/Export Capture as) so you can work with it in Netfabb.

b.- Vi3dim (software)

With Vi3Dim software you are able to built 3D models of textured objects, using only a standard computer and a camera. 
 
I used the tutorial that you can see in his website    

After recorded the video I launched the program.

At the begining it looks like the program were working.

But when it began to make the point cloud the program crashed.

It happened with three different movies.

c.- Modela scanner (hardware)

Finally I tried to scan a toy helmet with the Modela. I used the program Dr.Pizca

The results were not very good.

I thing the problem was on the resolution parametrers (1 mm).

I have no enough time to work with the mesh.

I will try again with others parameters 

2.- EDIT AN PRINT AND OBJECT THAT YOU SCANNED

First, I used Netfabb to clean the junk around the object, slice off the bottom to create a flat surface and repair the holes in the mesh with the automatic repair tool.

Then I exported the file as a STL file using Part/Export Part/STL

After that I used Meshlab's poisson filter to smooth out the surface of the mesh.

Before applying the filter:

After applying the filter, I did not see many difference.

Finally I slice off the bottom to create a flat surface again in Netfabb

You can find a very in depth explanation of this process in chapter 9 of the book Getting started with Makerbot by Bre Pettis, Anna Kaziunas and Jay Shergill.

To print the object I used a HP Designjet 3D Printer with the Designjet 3D Software.

After I choose the orientation, infill, layer height and the scale of the original model, the program slice the object.

Now, we just have to send the file to the printer and wait till it finish.

Final files:
ovejita.stl