[Alex] from Tinkerlog has revisited an old project with Synchronizing Fireflies NG. Fascinated by how fireflies blink at same rate and synchronize with each other, he built a digital version. Each board has an RGB LED and a phototransistor or photoresistor. A ping-pong ball is used as a diffuser. The blink rate is controlled by an ATtiny13v. The board power can be daisy chained, but each firefly mote operates independently of the others. The microcontroller has a fixed flash rate and monitors for other flashes. It attempts to sync by flashing earlier. The color of the LED expresses how satisfied the firefly is with its current sync. You can see a video of eight fireflies attempting to self organize embedded below.
attiny181 Articles
Breath Controlled LED Candles
Instructables user [cedtlab] has posted an interesting LED project that simulates birthday candles. The circuit runs on an AVR ATTiny45, and is powered by 4 AA or AAA batteries. By using a Charliplexing technique, they are able to drive all 20 LEDs with only 5 pins of the ATTiny. A thermistor is used for detecting breath by measuring temperature changes, and then blocks of LEDs turn off depending on the change detected. They have provided schematics and source code for everything. Make sure to check out the video of the “ficticious birthday party” after the break.
Perceptual Chronograph
All praise to [Limor] for uncovering this incredibly odd project. [magician]’s perceptual chronograph is designed to test whether time “slows down” in stressful situations. The device flashes a random number on the display very quickly so that it is impossible to perceive what is actually being displayed. If you can read the number while under stress, it means that your ability perceive time has increased. It’s hard to believe, but check out the video embedded after the break that investigates the phenomenon. We can’t help, but wonder how [magician] personally plans on testing this.
Random USB Caps Locker
This is one of the most original April fools gags I’ve seen. [Garrett] sent in his USB caps locker. It’s built from an ATTiny45 and puts out an intermittent signal to set the caps lock key. Considering what day it is, it appears to be legit. After you’re done screwing with your co-worker for the day, you might be even more interested in the easylogger project that it’s based on.
Simple Capacitance Meter
[Mike] sent in a project he’s been working on lately. This little circuit can measure the capacitance of a capacitor by generating a frequency that’s inversely related to the capacitance. He originally got it working with his o-scope, and followed up by building a stand alone version that uses an ATTiny2313 and a text LCD.
Thinkpad Style Keyboard Light
[Sprite_tm] keeps coming up with nice work. This time he sent in his thinkpad style keyboard LED lighting solution for his toughbook. I know, you’re thinking… ‘it’s a LED…’ He used an ATtiny13 to monitor the caps lock LED. If it’s operated two times in succession, the LED is turned on and off. Nice, clean and effective.
[By the way, Part 2 of my diy projector how-to is up on engadget. Look for part 3 later Tuesday.]
