Showing posts with label cameras. Show all posts
Showing posts with label cameras. Show all posts

3D scanner

Friday, 28 June 2013
3D scanner
Prototype.
Simple but works well.
Digital camera with video recording function (resolution: 640x480, 30 frames/sec).
Laser pointer with special ending for linear beam (ending from laser level).
Phonograph as a rotational drive. Modified with low speed motor and Arduino.
Board and measuring tape.


How it works?
Digital camera placed in phonograph axes of rotational record laser light on objects surfaces (it works better in the darkness). Distortion of laser line corresponding to objects deformation derive from location of laser source. Very important is constant rotational speed and precise measurment (calibration).

Based on scheme and calibration value (a,b and c) we can calculate coordinates of every scanned point.


Software.
I wrote special python script for converting video direct to point cloud in Blendera 2.49b. Script require Python Image Library (PIL-1.1.7.win32-py2.6). PIL require conversion from *.mov to *.gif format (but *.gif works with only 256 colors).
Helpful documents: PIL handbook, Blender 2.49b API.


Results.
Blender screens of room scan:







Scan parameters:
  360 degrees scan,
  video recording time: 82 sec,
  'video to point cloud' conversion time: 115 sec,
  number of generated points: 72 000.
Sample point cloud file: Room.blend.

Sample face scan:

Scan with auto faces generating script:

Mesh after a little processing:




What next?
This construction is better for scan large object. There are some problems with scan in light places and with shining surfaces. It is also interesting a choise of video filter (sometimes it is better to work with red laser on green channel than with red).
Now I am serching for best 'points to surface' algorithm (generating triangle or quad mesh).
See open source MeshLab'a.
Read more ...

Pocket Projector

Friday, 28 June 2013
Overview
Photo Build Log
Pocket Projector

cameras made me wonder just what could be done with their all of the lenses they had inside.  a bit of testing showed that certain combinations made it relatively easy to project images from a film negative.  I rounded out the project by printing a reel of “film” on transparency paper, adding a light and a film advancement mechanism, and throwing the whole thing in an altoids tin.
update: hackaday feature link
Research.html

Projects.html
InterestsInterests.html

The Lenses:
Lens attachment and Film reels
Second lens and light source
Nearly complete interior, film advance knobs, and light switch
It Projects!
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