Jar of fireflies

[Randomskk] has been attempting to make electronic fireflies for quite some time and finally settled on a design he liked. His jar of fireflies uses an ATtiny13 to control a set of 12 matrixed LEDs. The green SMD LEDs are each soldered to a pair of thin wires that hang down into the jar. The software picks an LED at random to flash and then flashes it 1-3 times. The random seed is incremented each time the jar is turned on, so you’ll get 255 different patterns. The power is just a standard coin cell. The project is fairly simple electrically, but the LED soldering could prove difficult. It was inspired by this firefly jar project. Check out [Alex]’s synchronizing fireflies too. A video of the jar is available below.

Comments [13]

tagged: fireflies, firefly, firefly jar, led, led matrix, matrix, randomskk, smd

Reader Comments

Wonderful… Childhood memories. Phase two should add an actuator that moves the wires, letting the positioning also be as random as the patterns.

Posted at 6:35 pm on Oct 18th, 2008 by YoYo-Pete

I feel this [blog entry] is a total pile of crap. Granted you acknowledge the original idea on instructables; but why not feature the original (and far better) jar of fireflies, and say ‘this other guy did it too’ instead of saying ‘this guy built a version of this other guys idea’.

Just my humble opinion.

Posted at 7:15 pm on Oct 18th, 2008 by Frollard

Yes, why wasn’t the first fireflies-in-a-jar projected presented instead of this?

Also, this idea is begging for the addition of a solar cell & charging circuit extracted from a solar garden light – fireflies that appear every night without the need to replace batteries.

Posted at 7:49 pm on Oct 18th, 2008 by Haku

Would benefit from thinner wires.

Like 30 gauge enameled wire

Posted at 1:43 am on Oct 19th, 2008 by Tim

Thats what the original uses…check the instrucatble link.

Posted at 1:49 am on Oct 19th, 2008 by Frollard

It could definitely do with some thinner wire, but in the dark you can’t really see the wires anyway, so it does still work fairly well.

A solar panel would be a nice addition too (I might pick up some small calculator ones and rig them up so they sit on top of the jar), but as it’s kept indoors I doubt it’d get much light. An outdoors version with LEDs rigged to plants could really benefit from a medium sized panel hidden somewhere, though!

frollard: the idea is the same, but the implementation is pretty different – the one at instructables has multiple songs and lights up a few at once, but takes ten times as much code (so needs an attiny45) and only controls six LEDs. I still think having 12 LEDs controlled by 5 pins and still having hardware PWM control of all of them is interesting, even if it is basically charlieplexing.

Posted at 2:33 am on Oct 19th, 2008 by randomskk

i read the instructables one first; and yeah it’s a much better article and hack

shame on you!

Posted at 10:00 am on Oct 19th, 2008 by jim

Hackaday keeps on removing my posts just because they have bad feedback. click on my name below to visit a website that allows comments of all kinds

Posted at 2:12 pm on Oct 19th, 2008 by diy2345

@ Diy2: No, they remove it because you belittle hackaday while telling people your crap site is better.

Posted at 8:21 pm on Oct 19th, 2008 by cde

If I recall from my days of catching fireflies in a jar, when one would light, they’d all light up, so you’d have an entire jar lighting.

Fireflies exhibit the random lighting only when they’re out in the wild. Put them all together and they make a nice momentary lamp.

Posted at 5:40 am on Oct 20th, 2008 by AC

you should rig up a fan in the jar so that the lights move around, simulating firefly flight.

Posted at 1:07 pm on Oct 20th, 2008 by anon

Take a look at FireflyMagic.com/jar for the original “Fireflies in a Jar Kit”.

They supply these devices to theme parks, zoos, nature centers, museums, and to stage productions, movies, and magicians.

Their ‘Fireflies in a Jar’ were recently used in the Tennessee Williams play a Rose Tattoo at the National Theatre of London.

They also have ‘Fireflies in a Jar” that operate on rechargeable batteries and have a solar panel on top of the jar for solar recharge.

And, they even build battery powered units for Universities for use in the field to lure in real fireflies. Firefly Magic has been acknowledged in scientific papers for their work in this area, and for their patented technology that accurately recreates firefly flash patterns.

Posted at 3:08 pm on Oct 21st, 2008 by SJT

I know I’m late to the party, but this post (as well as the Instructables post) inspired me to give this a go too. Admittedly, I used standard (large) LEDs but added some shrinkydink to make up for it ;)

http://fangletronics.blogspot.com/2009/05/jar-o-fireflies.html

I also ‘hacked’ my fireflies to run off solar power after finding some dirt cheap solar-cells (with charging circuit) on allelectronics.com (http://www.allelectronics.com/make-a-store/item/SPL-07/SOLAR-CELL-W/CHARGING-CIRCUIT-1-RED-LED/-/1.html)

http://fangletronics.blogspot.com/2009/06/solar-powered-fireflies.html

Those solar cells should be pretty useful for a number of projects (I bought 4 to play with).

Posted at 3:17 pm on Jun 25th, 2009 by PaulBo