During the last few months miceuz, Vilius and others have been developing an open source modular laser maze. We’ll install it at the hackerspace, bring it to Vilnius Mini Maker Faire and No Trolls Allowed hackercamp, let artists play with it – it can be transformed into anything from a security system to a laser harp that drops confetti from above on certain notes.

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The first system will consist of 20 green laser pointers coupled with detectors, powered by Li-ion batteries. Other specs include:

  • More than 10 h operation on a single charge;
  • Wireless data transfer at 433MHz;
  • Latency up to 5 ms;
  • Vibration tolerant sensor (4 phototransistor grid in a 3D printed case)
  • Portable, easily reconfigurable – standard microphone stands should be used as a means to mount and configure lasers and sensors.
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The original idea was to have lasers as dumb always-on battery+laser assemblies, but after some thought we decided that it would be a good thing to have means to switch off lasers too - it would prevent them from overheating, extend their life and create a possibility to play cool effects by switching and PWMing them. In order to keep price down we have decided to join the laser and sensor together in a single assembly, sinning  a bit against the the totally-wireless idea we had in the beginning by using a relatively short cable from the laser module to the main sensor/MCU board.

In order to have a two-directional communication possibility we decided to test RFM69W modules - there’s plenty of example code floating around on the net so we wouldn’t have to reinvent the wheel. The test turned out to be OK, we were able to get reliable communication across the room and the latency was 3.16 ms.

miceuz is writing a build log here, check it out for more details. All code and hardware (heat sink schematics, PCBs, 3D models) are on Github.