Sucess! Basic functionality test.

I think I’m just about as excited as a six year old on Christmas Eve night. I have great news to report! I now officially have limited basic functionality on my multi-touch table! Granted, right now it is neither multi, nor touch. I am using an IR-pen until I get my illumination set up so all I’ve got is single-point touch.

I am using the marvelous Touché framework and I can’t say how awesome this framework is already. It’s only in it’s second beta incarnation and already has a very beautiful UI, intuitive setup process, and from what I can see without having written any code yet: good development capabilities. Setup was very quick and in about 10 minutes I had everything tweaked how I wanted it.  Hopefully in the future we’ll see fiducial support and the ability to tie actions to custom movements instead of being limited by touch, double tap, and pinch.  But again, Touché is only in beta 2 so it’s got plenty of open road ahead.

Right now everything is running off my Mac Mini.  It makes tracking just slightly laggy, but it’s really not bad at all and I was expecting it to be much worse with such a small computer.  The final product will be run off a Mac Pro and as such should have no problem with lag.

I’m now moving on to finishing the design of my IR illumination setup.  It’s going to be a hybrid of LLP and FTIR using much safer LED’s instead of lasers.  Hopefully in the not-too-distant future I’ll have touch ability done.  But for now, this gives me plenty to work with in starting to develop my software.

Covering the back side of my LCD with tracing paper.  This diffuses the backlight and gives perfectly even light.  My camera now is completely un-noticeable and does not cast a shadow on the screen.  The seams of the backlight enclosure have now completely disappeared.

The Unibrain Fire-I camera inside a white enclosure that holds the Thorlabs filter in place.  On the left is one of my reflective backlight enclosure panels (thin composite board covered with a sheet of Mylar)  The other three sides don’t have the enclosure panels installed yet.

Time to get Touché!  Notice how the image has completely even illumination even without the rest of the backlight enclosure in place–thanks to the tracing paper.  Also notice how the white areas look grey and a bit dirty when viewed at full size.  This is because the tracing paper has a slight texture which you can see from the top.  Not a major deal at this point as it just looks like you are looking through a dusty lens.  However, this will obviously have to be replaced with a different sheet of texture-free tracing paper.

Touch the glowing white dot!  Calibrating the screen.  Extra important with the 2.1mm lens on the camera.  Touché did an excellent job with calibration and once I had my filters setup correctly I only had to calibrate once and everything was spot-on.

Playing with the thumbnail app.  Right now to rotate you have to grab and drag on the corners of the image.  Hopefully a future version will allow you to use the two finger “twist” approach that is a bit more common.

Coverflow baby!  Oooh yeah!

The little things…

I finally received a portion of the exterior paneling that will be bolted on to the aluminum frame and also provide the surround for the backlight.  I thought I’d update on the little projects that are keeping me occupied while the rest of the paneling is finishing up it’s design/manufacturing/application process.

One of these is the camera enclosure which will serve to hold the Thorlabs IR filter in place over the camera without having to use poster tack around the lens.  It will also completely enclose the camera and hopefully cut down on the dark footprint in the middle of my backlight.  The enclosure is a simple box which will be covered with Mylar just like the walls of the backlight.

My second little project was one I just completed today.  Since I don’t have my IR-illumination fully designed and implemented I wanted to be able to calibrate and test out the table while I finish the infrared LED frame.  My solution was to take an ink pen and convert it into an infrared pointer that I can use as a “single touch” input method.

I pretty much just followed the instructions that I found on this website: http://www.terracode.com/IR_Pen/DIY_IR_Pen.html

I used one of the SFH485 LED’s that I already had and bought the largest barreled ink pen I could find at Walmart (a whopping 98¢ … gotta love Walmart!)  I ended up using a AAAA battery which was still 1.5V but would actually fit inside the barrel of the pen with just some minor modifications for the wiring.  I also bought a much smaller momentary switch at RadioShack (part number 275-0008 for anyone interested)

I was able to solder everything and fit it all inside the barrel of the pen.  The rubber grip on the pen was removable which allowed me to cover up much of the cutting that I did to the barrel to accommodate the wiring.  The good thing about this was that it also allowed me to completely cover the momentary switch which gave me an invisible, pressure sensitive on/off point.

Here’s a short video of my results, the second half shows what the pen looks like with my IR bandpass filter over the webcam.  As soon as I finish my camera enclosure I can start actually testing it on my table!