RGB LED Coffee Table

Just a little preview of a project I'm finishing up now...IKEA Granas glass top side table with a 2 foot square 9x9 array of ShiftBrites.

Sweet!

Looking forward to more imgs. And a video? :D

Okay here's a video, using an Arduino to calculate a sine plasma realtime and do HSV to RGB conversion: http://www.youtube.com/watch?v=C7aUaMiqoIE

I think I'd prefer it if it had a more frosted glass top, to spread the colours into each other a little more, but I love this idea for a table installation. Wish I had something similar - I think I'd like to combine it with sensors to interact with objects on the table as well.

The glass frosting film I used was a little disappointing, more of a refracting effect. I have some lighting panel plastic I'll drop on top of the LEDs to mix the light a little better, but that will still be an inch or two below the surface. I kind of like the depth effect, actually. But I'll play around with a few materials and ideas, maybe come up with something that looks like solid square pixels.

That's $405 in headerless shiftbrites :o

he SPARED NO EXPENSE

I make and sell them so there's always plenty of ShiftBrites hanging around. There ARE quantity discounts, so more like $313 in LEDs, but I also used cables which brings the total back up.

The coffee table looks fantastic... I just saw one of those tables at Ikea a few weeks ago. :P

Are these all in a single 81-SB chain?

Can you post the source code you're using for this?

Nice!

What are you using to drive the LED's ?

I’ll post the code pretty soon…right now, in the last minute rush for Maker Faire. The coffee table will be there.

The ShiftBrites are in a single chain of 81, but voltage drop is too much so I have power injected every 9 modules. The Arduino code is pretty simple, hopefully will have time to expand it before the Faire.

Ah, I hadn't considered the voltage drop! I currently have only 16 SB units in a single chain, running from an ArduinoMEGA (fantastic device). Occassionally (fairly randomly) my string will start to flip out displaying strange colors and brightness levels. I haven't found a reason for it, and it seems to happen regardless of time, output pins, or sketch driving the string. I will measure voltages along the chain to see if this is the problem. Currently I am driving my chain using a re-purposed 250W PC Power Supply (15A avail).

Best of luck at the Maker Faire! :)

Its a cool project! In response to the post about the cost, the shiftbrigtes are an expensive solution when so many LEDs are used but don't let that detract you from making a coffee table! Normal mortals who don't have an infinite supply of shiftbrites can use the MAX chips which drive 64 LED arrays or the M5451 which can drive 35 individual outputs. If you do software strobing with 2 M5451s, you could theoretically do 400 (35*35/3) RGB leds, although it would have to be tried to see if there is discernable flicker. Or you could directly drive each LED, and use 6 M5451 chips to get 70 RGB LEDs (6*35/3=70). Since the M5451s cost about 3.50, if you use strobing the main cost would be the LEDs and the Arduino. I bought 50 awhile back for about $25 I think, so say $50 total for a barebones Arduino+M5451s+LEDs.

I made an M5451 library that you can get here: http://code.google.com/p/arduino-m5451-current-driver/ but I haven't added strobing to it; that might be a fun project.

The nice thing about the shiftbrites is that they require 4 wires (plus power), they have their own built-in PWM, so you blast a data stream out to them, then go onto whatever other code you have, no multiplexed column scanning to bother with. The price really isn't bad for the functionality either, they're amazingly easy to work with.

Neat project. You might like this one too:

http://www.circuitcellar.com/designstellaris2006/winners/1682.html

Not exactly the same, but perhaps you'll like it.