Laser Beam System Trial

This week Terry and several engineering students from the University of South Australia came to the park to trial a new laser beam counting system at Bat Cave. They brought four lasers along to test. The overall goal is to have 12 permanently-installed beams running across the entrance of the cave. The lasers will record all night, every night. They cannot tell if a bat is flying into or out of the cave, so we cannot get actual numbers. However, we can get an index of activity, which will give us information about when the bats return to the cave in the spring, when the activity peaks in the summer (at which point we can use the thermal imaging cameras to take actual counts), when the pups start flying, and when all the bats have left Bat Cave for their overwintering caves. It’s pretty exciting stuff!

Of course the field testing didn’t go quite according to plan (does it ever?). The lasers were very difficult to align with the receivers since the beams are infrared and we can’t see them. The students had to use a neat night vision application on their smartphones to see where the laser was hitting the receiver, and then try to relay directions (up, down, more left, a tiny bit right!) to the person moving the laser. And then we had the problem that the lasers kept double-counting. After fiddling with them a bit, the students got them ready enough to trial at an emergence at the cave. We got to see them in action, even if they still needed a bit more work. Terry decided to take them back to Adelaide to work on them so they are easier to align (and also to figure out a more stable mounting design), but hopefully they will be back soon and we can begin using them!

Trying to align the lasers (left) and the receivers (right). A harder task than it may sound.

Using a night vision application on their smartphones to align the lasers, this time at the cave.