2,300 mile touch over IP

On Saturday, I guest hosted & presented at Dorkbot SoCal.  Along with Damon Seeley who showed off some super projects by Electroland (including live video from their Target Breezeway in Rockefeller Center), Gilad Lotan who showed some of his projects including the heartbeat-sharing imPulse, and a discussion of the Make:Way entry to the 24 Hours of LeMons race, I demoed touching someone 2,300 miles away over IP. Douglas Welch shot and edited this great video of the demo:

First "real" PCB

Back in high school, I made some PCBs using resist pens and etching the copper, but nothing very serious.

I decided it was finally time to try using the free Eagle design tool along with BatchPCB.com service to make a PCB. My issue was that the wonderfully cheap Lantronix Xport Direct uses 0.2mm spaced pins which are a pain to interface to. So I figured this would be a good opportunity to design a PCB with a 3.3V power supply and the Xport broken out to 0.1" spaced standard headers.

The boards took about 3 weeks from submission to delivery (which was over New Year's so it might be faster for you), and cost $24.60. For that price you get two boards (this was a 3.8 sq. inch design).

So I populated the board and hooked everything up, and it appeared to work fine...until I started smelling something burning. I powered down, and after a short reference of the LM1117 documentation, I realized even though the regulator is only providing 200mA to the Xport, with a 9V supply the regulator needs to dissipate ~1.2W, which multiplied by the thermal resistance of the SOT-223 to ambient of 136 degrees C per Watt, means the regulator is warming up 163C above room temp, about 183C. OK, that is a little hot!

Max junction temperature is 125C, so if room temp is 20C, I can get by with 100C rise which for 1.2W implies a heatsink with a thermal resistance of ~80C/W, which means 0.3-0.5 sq. inch of heatsink (two wings larger than the size of the actual chip). Anyway, next time I'm doing at least a TO-252 or just go TO-220 with the ability to add an external heatsink if needed.

For the short term, I think I can jury-rig an external heatsink, but the lesson has been learned for my next design: an Ethernet-enabled Freeduino.

Here is a link to my Eagle library for the Lantronix Xport Direct.

If you need a PC fast in LA...

Here is my suggestion if you need a PC fast in LA:

PC Club

Move and SymbioticA

I recently moved to Los Angeles, so last night I hit Machine Project to go see Oron Catts & IonatZurr of SymbioticA speak about tissue culture art. Definitely cool stuff!

iTunesU has a neat video about creating art-games, go to the iTunes store and search for
"joe mckay finding balance".

More info here:

http://hci.stanford.edu/cs547/abstracts/06-07/061006-niemeyer.html

You can also check out Joe McKay's website.

Dorkbot DC Meeting September 10, 2007

Dorkbot DC is a monthly meeting of artists (sound/image/movement/etc.), designers, engineers, students and others in the DC area who are interested in electronic art (in the broadest sense of the term.)

Next Meeting:

Monday, September 10, 2007
7 PM - 9 PM (ET)

Marian Koshland Science Museum of the National Academy of Sciences
6th and E Streets, NW
Washington, DC 20001

(PDF Meeting Flyer/Poster)

Presentations will include...

Conrad Barski: PicnicMob.Org

PicnicMob is a concept to create "flash mob" picnics in parks of major U.S. cities, but it assigns each participant to a location in the park so that they are near other participants with similar interests (calculated using simulated annealing).

Thomas Edwards: "Touch"

Mechatronic and robotic artist Thomas Edwards will present his work "Touch" which allows two individuals to physically touch each other over the Internet. During the meeting, Edwards will demonstrate touching fingers between Washington, DC, and Toronto, Canada.

On the other side will be Liav Koren at the University of Toronto's Faculty of Architecture, Landscape and Design. "Touch" is part of the Phy2Phy project to link physical artworks over IP.

Philip Kohn

Philip Kohn will lead a tour through "The Looking Glass" , an evolving interactive video piece that encourages participants to move about in silly ways by rewarding them with cool effects when they do.

He'll reveal plans for a new (hopefully!) commissioned collaboration with ceramicist Novie Trump called "Through the Hedge" which will create an artificial real-time jungle including magical creatures that do things to you when you touch them. It will attempt to blend and bring life a large ceramic mural with an embedded huge LCD flat screen.

If he gets it together, he may also debut a new piece called "Feeling Lucky" which crawls along the web as a stream of consciousness in pictures using Google image and Google search.

For desert, he will offer "Pastry", a recent piece that shows organic layers of texture that come out of the screen, without the need for 3D glasses.

Real Life to Second Life

I'm investigating having "Touch" bridge between the physical world and Second Life.

There are a couple of mechanisms for objects in SL to talk to the outside world. Andy Fundinger has a summary of the three mechanisms here. The one that makes the most sense for "Touch" is probably having the object do HTTP requests to the outside world using llHTTPRequest.

Touching distance

It turns out a more accurate translation of the last bit of the Make:Japan blog entry about touch is:

From Translator: As far as I can tell from the video, it looks ordinary. However, reading this explanation, it sounds innovative. I wonder how I can use this for what, though. I can't think of any idea for it, from this mediocre brain....

I was thinking that when I "touch" between DC and Toronto, it won't just be 356 miles between the two cities, but actually the "touch" signals will go between DC and Sunnyvale, CA (where the server is, 2429 miles away) and then to Toronto (2262 miles away), for a total of 4691 miles.