Getting Your Message Across At Commencement

June 8, 2010 by Mike Szczys 33 Comments

[Yomagaocho] is graduation from Northwestern University on June 18th (wow that’s late in the year… they must be on quarters). He decided to spice up his mortarboard for the commencement ceremony. A normal message wasn’t good enough, and even a solar-powered diorama wasn’t going to suit him. Instead he added 256 addressable LEDs to the top so that he can get his message across without being limited to a couple of words. See it demonstrated after the break.

He was nice enough to give us the technical details. The matrix is a 16×16 grid mounted in some laser-cut black acrylic. We immediately wondered about the display working in sunlight (a June graduation will probably be outside). He didn’t use any current limiting resistors with the LEDs, dangerous to the longevity but this should provide maximum brightness. It’s certainly a geeky concept, but having the ribbon cable that controls it trailing down into your robe might make those graduation photos a bit embarrassing a few years down the road. Continue reading “Getting Your Message Across At Commencement” →

Wire-wrapping An LED Matrix

June 3, 2010 by Mike Szczys 20 Comments

Regular reader [Osgeld] built a 1024 LED display matrix. This is a proof-of-concept design and he admittedly has overloaded the components. Most notably, the 595 shift registers (featured over the weekend) are sourcing too much current if all eight pins are active. That’s easy enough to fix in the next design by moving up to cascading LED drivers. Instead of soldering every connection in the display, [Osgeld] soldered the components in place and then used wire wrapping to make the point-to-point connections. This must have saved him a ton of time and frustration. We can’t wait to see what comes out of this first prototype.

Laser Command Game Uses Laser For Control

May 4, 2010 by Mike Szczys 31 Comments

[vimeo=http://vimeo.com/10819322]

[Eliji Hayashi’s] project for a class at Carnegie Mellon University is absolutely delightful! It is a game he calls Laser Command because a laser pointer is used as the gaming controller. An 8×8 LED matrix serves as the display, but is also used as an 8×8 light sensor, much the same way as the LED advent project did. The display is rapidly switched between producing light and sensing it. The laser is bright enough that it becomes easy to pick up the voltage generated within the matrix during the sensing periods. The game is programmed on an Arduino mini and the whole thing wraps up into an incredibly small package. Brilliant.

[Thanks Juan]

Twittering Pub Hanging

April 20, 2010 by Mike Szczys 19 Comments

There’s nothing groundbreaking about this hack, called the TweetWall, but the craftsmanship is gorgeous! [Yergacheffe] had access to the right tools; an epilog laser and a thermoplastic bender (an item we didn’t know we needed until now… thanks a lot). It has the usual bits you’d expect in a Twitter ticker, an LED matrix and an Arduino. There is also an OLED screen that displays the avatar of the current Twitter feed. Because data is transferred over a serial connection the SD slot on that screen is used to cache images which helps to keeps the messages coming without delay. The end product is quite good, we’d expect to see it hanging on the wall of the pub down the street.

112-LED Coffee Table

February 28, 2010 by Mike Szczys 30 Comments

[Joe] tipped us off about his 112 LED coffee table. This 12-ups the LED matrix from Friday and 31-ups the Shiftbrite table. Driving this grid is an ATmega328 in i2c slave mode. It listens for display data from a second ATmega328 and uses that to set the array of TLC5940 driven LEDs appropriately. Separating the processing microcontroller from the display microcontroller allows for fast and smooth display changes that can be seen after the break. [Joe’s] table exhibits exquisite cable management, clean code, and an amazing amount of flexibility. Maybe [Caleb Kraft] will finally pony up the dough and make this project for his own home.

[Joe] waited until he saw some other LED tables to send us a link to his hack. This is obviously an awesome project, one that we want to see just as much as our readers do. So please, don’t wait for someone else to stumble upon your project, send us a tip once you’re done sharing the details.

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Two Input Devices Made With Common Items

February 27, 2010 by Mike Szczys 19 Comments

Here’s two input devices you can easily build with materials you already have on hand.

To the left, [John] built a 3×3 keypad matrix from paper and tinfoil. The rows and columns are made up of strips of tin foil on the front and back layers of paper. The layers are separated by spongy double-stick tape. A ‘keypress’ results when the gap between the conductors is compressed with your finger.

In much the same way, [Dave Fletcher] built a touch potentiometer. He made two resistance plates by scribbling pencil lead on sheets of paper. When the two plates face each other, separated by the same type of foam tape as before, they can be pressed together to form a circuit with a variable resistance. This results in a crude version of the SparkFun softpot.

10×10 LED Matrix

February 26, 2010 by Mike Szczys 33 Comments

[KopfKopfKopfAffe] just finished a 3-year labor of love resulting in this 10 by 10 LED Matrix. This trumps the Shiftbrite table from earlier today by bringing an actual 100 LEDs to the display. These LEDs cost much less than the Shiftbrites, but since they don’t have their own on-board controller this project requires much more back end work. A total of 25 ATmega8 microcontrollers drive this display, in turn controlled via an RS-232 connection to a computer.

We love the Lemmings animations. It made us realize that this would be a great candidate to play Super Pixel Bros on. Check out the video after the break for snapshots of the hardware as well as videos of the matrix at play. You may also want to peruse the translated work log.

Continue reading “10×10 LED Matrix” →