Photos of webcam scanner. ( no laughing.. :) )

[ART]

Hi Guys:

  Here are some photo's , though grainy, of the "scanner" I made for this. Its a piece of wood with a laser pointer pressed in a drilled hole.
The angle of the hole was arbitray, ( my vise was at that angle..) , the plugin calibrates the angle and such with the 2" wooden block in one
of the photos. The laser takes 5 volts, taken from the red and balck wires in the webcam cable. The block of wood is then clamped with a
spring clamp to the upper or lower spindle trunion ring mounts depending on the FOV I want to shoot on.. ( I find higher makes the line sharper
and gives better results.. )  . As you can see, its a very expensive, very sensitive, very complex uint, likely as high as 50 bucks on the open market..

Art

[ART]

oops , forgot the photos..

[ART]

and finally, some grainy closeups..

[Bodini]

Webcam: $30
Laser pointer: $6
Spring clamp: $3

Arts bare feet:  Priceless.

 

-Nick

[Bodini]

Oh yeah, forgot to mention that the video probe is flippin' sweet.  I REALLY have a use for that (even in a not-perfect state).

-Nick

[ART]

The 60's were good to me, I hate socks..

Art

[aolshove]

Awesome job Art!  I'll sign up for the beta test when you're ready.  I even have a line painter/camera rig ready to go from when I was working on building a line scanner a couple of years ago.  Your hand scan looks way better than anything I ended up with. 

One trick I figured out to give clean points is to use a filter over the lens of the camera to filter out all colors but 650nm.  The other trick was to dim the lights during the scan.  Your scans look great though so you're probably beyond these problems.  How'd you deal with the distortion of the lens?  Did you use OpenCV or roll your own vision library?

[ART]

Hi:

  Now thats a good iead, the filter.. what did you use for the filter material, I hadnt thought of that one..
I use the same video ocx as the video plugin, the rest is home rolled in terms of analysis, It calibrates to a 2" block
to compute the laser plane, then I switch all the calcs to a angle vs plane intersection code that computes everything based on ray tracing.
Im still working on the variosu algorithms to centroid the laer better to remove speckle and such.. Im hopeing to have it search
for the best algorithm for a persons setup with reliable pixel detection as the arbiter.
   Ill release it when I figure its usefull , its lmost usefull now in many ways, but the sparckle and centropiding needs to be better
yet. A better camera woudl probably help, but Im staying with cheap stuff with the thought that if my cheap setup works good
then a good setup will be awesome..

Art

[aolshove]

For the filter I used photographic color filters. 

I got a Roscolux filter sample swatchbook  http://www.rosco.com/us/filters/roscolux.asp and experimented with various RGB combinations until I settled upon #19 (fire), #93 (blue-green), and #84 (zephyr-blue).

Got the swatchbook from Cascade Sound & Stage.  Looks like you can get a sampler directly from Rosco at http://www.rosco.com/us/filters/swatchBookRequest.asp?type=roscolux

You can also buy them for a couple bucks from various photographic supply web sites.  Got mine at B&H Photo for a penny. http://www.bhphotovideo.com/c/product/45189-REG/Rosco_8807_Roscolux_Swatchbook.html

[Hllrsr]

Art,
Any probable ETA on this oh so sweet addon?
I'm currently using Emc2 as (closed loop) control software, with a trial version of Mach on a second machine for the digitizing, but for this little gem I'd even be willing to dump the Emc!

Iain