Hello all,

This site has been a fantastic resource for my multi-touch experiments.  As such, I figured it’s about time I post my current project.

I am working on a multi-touch gaming surface in coffee table format.  I plan on going the DSI route and have purchased parts for that cause.

The current scale mock up of the table uses the following:

43"x24" 8mm ACRYLITE Endlighten
850nm IR RibbonFlex around all edges
A box approx 46"x30"x19"
An InFocus XS1 moderately short-throw projector
2 Acrylic mirrors (also from ACRYLITE)
A gigaware photo film negative enhanced IR filter removed webcam + 160 degree wide angle lense
A toshiba M200 running windows 7 for the brains.

I’ve posted a mini-blog on blog spot with photos and details about my experiences. 

http://multitouchgaming.blogspot.com/

Currently, I am working on getting the placement of my mirrors just right.  Additionally, I’m working on adapting RPTools MapTools software to work with CCV or reacTiVision. 

In correctly, I’m am currently using a sheet of Rosco Grey (which blocks the DSI) for a projection surface.  The plan is to use 7D512 or 7D513 for the final surface but I am waiting till after I’ve finished the plans for the housing.  Currently I’ve select maple as a primary wood for the box with birch ply for large flat surfaces.  The 7D51x will be larger then the Endlighten and by a few (yet to be determined) inches.  This is why I’m currently using the Rosco Grey.

Interesting notes:  The gigaware camera was extremely easy to modify.  It gets a decent frame rate but the wide angle suffers from being too wide of an angle.  Touches on the edges are unresponsive at best and more often completely lost in the noise.

Looking at the images from CCV, I see a large amount of ‘glow’ from the IR along the edges of the screen when using the gigaware.

I did try using two Hercules Dualpix HD Webcam 720p webcams which claimed to have wide-angle lenses to cover the range, but found that the range covered is simply too small.  The cameras themselves work wonderful and will be good for completing any of the smaller installations I began, but I would need to raise the height of the current project above an acceptable coffee table height for either of them to be useful in this project.

I have not tried bouncing the camera images into the mirrors yet, so that may end up as the solution.  we shall see.

The modification to the cameras was tough.  I friend desoldered the autofocus lenses for me and I used a mallet and microscrewdriver to crack the IR filter free from the bottom of the unit.  The process of desoldering destroyed the very delicate auto-focus mechanism.  This required that after reattaching the lenses to the board, I used the same micro-screwdriver and manual rotated the lense for focus.  Both cameras came out somewhat blurry, as in, I’m not going to be reading text with either of them.  However, for larger fidicules they should work just fine.

looks great. How are you liking the acrylic mirrors? do you mind posting a pic of your bounce configuration?

Thanks.  So far I like the acrylic mirrors.  I still need to remove the protective layer so as to make them first (front face) mirrors.  But over all I’m less concerned about them breaking and making me sad. 

I’ve got a link to the plans in this post on the blog:

http://multitouchgaming.blogspot.com/2010/01/framing.html

The image is higher res here: http://mongol.bu.edu/projects/multitouch_table/IMG_2026.JPG

Well, I was able to mount the two HD cams on spars off the sides of the box and use the rear mirror to capture more than half the screen in each.  Now I suppose it’s time to try out the CCV 1.3a with duo cam stitching!

The nice things about these cams is the clarity of the blobs.

looks great! similar to my DSI project… what endlighten are u using ? XL / XXL - 8mm / 10mm ? how deep are ur U-profiles ? would love to see more pictures of the box and the projecor / cam setup.

Thanks the_goat.

I’m using ACRYLITE® EndLighten, Clear 0N002 XL 10 mm:
http://www.acrylite-shop.com/US/us/acrylite-endlighten-crfo8s7j0ro/acrylite-endlighten-clear-0n002-xl-li7dvjay7nl~p.html

For the mirrors I’m using ACRYLITE® Reflections, Silver 0A000 X1:
http://www.acrylite-shop.com/US/us/acrylite-reflections-btj8cf35tag/acrylite-reflections-silver-0a000-x1-i3m89eiz92z~p.html

I’ll need to back the mirrors with something stiff in order to prevent the current curvature which is visible in the image at the top of this thread.

As to the question of U profiles, I’m going to assume you mean what channeling am I using for my IR Ribbon?  I’m actually using L channels and then creating the top edge with the foil tape.

I opted to use L rather than U to allow for building upward.  Also this allows for the IR Ribbon to only project into the endlighten and not any surface ‘glass I might project onto.  I _think_ this is the right way to go about the layering.

I’ll try to round up some additional pictures of the interior this evening and post them later tonight!

In the meantime I posted some pictures of my initial screen build in a blog posting here:  http://multitouchgaming.blogspot.com/2010/01/this-first-image-is-of-endlighten-l.html

I’m still using this screen without much modification.  The only modification I’ve made since the initial build is to afix some rosco grey so I stop blinding myself during my mirror tests.  Paper is cheaper, but I happened to have some Rosco around.

I’m not much of a blogger, so please excuse the verbal regurgitation.

Just a quick update: I received my sheet of 7D512 today.  My initial impression is less then thrilled.  using the same settings I’d been using to test with the Rosco Grey, I was unable to pick up any blobs what so ever.  Referencing Peau’s test settings (http://peauproductions.com/images/proj_blobs/acrylite_light_grey.png) I was able to get some minor blobs to appear.  The room I’m in has two windows and during the day has a fair amount of light.  This may be playing a factor, I’ll test again tonight.

[the_goat] I took those extra photos for you, I just need to resize them before posting.