Tom Padula's solar-powered electric fireflies are just one example of the kind of awesome homebrew tchotchke coming to the San Francisco Maker Faire this weekend. These things sound great: tinsy, solar-charged intermittent garden-blinkers that give you the fireflies you always wanted.
"The slightest breeze moves them around, and the motion combined with the light is mesmerizing," says Padula, who will be selling his digital lightning bugs for $10 apiece at the fifth annual Maker Faire Bay Area, which will be held this coming Saturday and Sunday, May 22 and 23, in San Mateo, California. The annual event, put on by O'Reilly Media, is a celebration of DIY culture, arts and crafts, and will likely draw more than 70,000 attendees, organizers say.
Padula's fireflies weigh 0.2 ounces (7 grams) and are attached to an 18-inch monofilament line. Six solar panels charge NiMH batteries, and a microcontroller drives the LED. The units are dipped in epoxy for weather resistance.
"All the real work happens in the code, from determining ambient light level, to controlling the LED intensity and keeping track of how long the pattern has been active so as to turn off after two hours, like real fireflies do," says Padula.