This is a big laser.
[3ric] from Hackerbot Labs gave me a run down of their BattleYurt laser installation at Toorcamp. It’s built with twenty-four 1 Watt lasers taken from a Casio DLP projector. The laser is housed on top of a yurt, which contains the controls and cooling system. It was built with the goal of measuring diffuse reflections of the atmosphere, but it also does the job of looking awesome when fired into the sky.
Since pointing lasers at planes is a bad idea (and very illegal), the Hackerbot Labs folks got clearance from the FAA through FAA AC70-1 to ensure airspace would be clear during Toorcamp. ANSI Z136 standards were followed to keep everyone safe. There were four emergency stops around the yurt, and motion sensors to ensure nobody entered the enclosure during operation. Tilt and thermal states were monitored to disable the system if it overheated or toppled over.
The cooling system consists of a custom heatsink and an array of Peltier devices that prevent the diodes from burning up. The whole thing is controlled by an Arduino, which cuts power to the laser if any of the safeties are tripped. The system was very well thought out, and they’ve posted details on the regulatory and safety aspects of the project.
Hackerbot Labs even added a Morse Code feature that sent out limericks during the camp. While many people had lasers at Toorcamp, Hackerbot Labs can take pride having the biggest, most powerful one.