These days everything about 3D printing is becoming more and more popular,
including 3D scanning. 3D Scanning is the process of converting a physical
object into a computerized 3D Model, which can then be used to print copies
of the object. The potential final process would be an actual 3D copier.
Once you see the scanner in action you will realize that the whole concept
is both complex and simple at once.
We acknowledging that 3D scanning cannot (yet) penetrate into a scanned
object. The goal of 3D scanning is to record the details of the surface.
Knowing that the object must have a closed surface from each primary
direction, this app measures each primary direction bottom to top. This is
why we use a turntable.
In order to capture all details of a specified angle, a vertically oriented
line laser is used. And here comes the trick: If you observe the image from
the side, you will note that the laser projects onto the object not as a
straight line, but as a curved line.
In areas where the object is wide, the captured laser light will appear at
the border of the image. If the object is thin at a particular angle, the
captured light will instead appear in the center of the image.
Illustrated guides can be looked up at SJ Bakers Wiki . This is where I maily derived my project from.
Before you can scan an object you must have a device in place which assists
in automatically rotating, lighting and recording a video of an object. One
of many options is to build a
turntable like the one at
These are the first basic steps toward getting your 3D scan.
To start you must record the required video.
If you cannot wait, or you do not have a turntable (yet), there is an option to
install predefined Videos like
. Install the app from the Google Playstore and have it ready on your
Procure a turntable. The main components are: the skeleton, the laser, the
motor and a surface to put your object on.
Optimize the line laser settings: First adjust the lens so the beam is
as thin as possible. Then adjust for vertical orientation of the beam, and
finally, point it precisely to the center of the turntable.
Once everything is in place, put your object on the turntable. :)
Turn on the motor and the laser, making sure to film in a dark
environment for better end video quality.
Start the app and put your android device somewhere secure and still
for filming. Make sure it cannot move or fall.
The filming and editing options of the app are divided into 4 sections
which are labelled 1/4 through 4/4.
In the first section you will find the record options. Use record to
capture a nice video of the rotating object. Make sure to capture at least
one full revolution. Do not worry about recording extra video, as there are
options to edit this out in later steps. Once one full revolution is
captured, stop recording and save the video.
Unless you want to repeat your recording, the turntable is no longer
needed. At this point you can turn off the motor and the laser.
In order to use them, copy them onto your android device and put them as
Scan3doid/Capture.mp4 in your movies folder.
The next steps are to edit the video into a useable file:
Start Time: Click into the video and you will see a time bar that
allows you to set the starting time. Choose any start point at the beginning
of the video.
End Time: This is the same procedure as Start time: Now you need to
make sure to choose a point where the object has ended one EXACT revolution.
Once finished, alternate pressing Start Time and End Time to check your
Bottom Line: Use the right hand slider to point to the exact horizon
between the object and the turntable.
Top Line: Use the right hand slider to point to the very top of the
X Origin: Use the top slider to point to the center of the turntable.
If you don't see it, you can estimate it.
Angular steps: Amount of calculated points around one revolution.
Vertical steps: Amount of calculated points from Bottom to Top.
Object height: Is specified in mm. The resulting object will have this
Maximum Object radius: Maximum distance from turntable center to
Masks: If the camera captures light in addition to the laser and not
intended to be filmed it can disrupt the 3d scanning algorithm. Adjust masks
with the sliders to avoid these effects.
These are the main settings. If they have been set properly, you can
select Process Video.
Once finished, press "Save STL". This will store an stl file called
"scan3doid.stl" on the external storage of your android device.
Before transferring the STL File off of your device, its advisable to
use an STL viewer to first view the result.
If the end result is not yet perfect, fine-tune your chosen parameters
and try again.
Once you are satisfied, you can press "Export STL" to export the file
from your device for further reuse.
This system is not yet perfect. Known problems are:
The lasers line is not infinitely thin. It has a real thickness, which
is about 3mm depending on laser quality. This results in an uncertainty, so
the digital model could deviate by that amount.
Only details which are lit by the laser and captured by the camera can
be translated. Hidden artifacts will not appear in the digital model. This
means record only the objects surface and no inner structures. Points on
the surface which are obviously missing will be interpolated from the