discussion / Camera Traps  / 4 July 2021

Structured light/lidar /laser for measuring animals in camera traps and BRUVs.


I checked through the site but couldn't find any information, please let me know if I have missed any threads.

I was just wondering if anyone is using or tried to integrate camera traps or BRUVs with any of the tech like structured light, lidar or laser triangulation to be able to accurately measure animals in the wild and potentially gather other information like growth or nutritional status.

The system in the new iPhone seems relatively easy but low accuracy, and 3d scanners are realively cheap now especially with the boom of 3d printers.

Adding a structured light illuminator should not be too complicated but for what I read is not great for moving objects. 

Triangulation 3D scanners emitting a laser line are capable of scanning moving objects so could be more suitable... 

MBARI just published a paper using laser to rebuild the 3d structure of underwater animals (giant larvacean) in a super cool but complex system on their ROV.  https://www.mbari.org/deep-piv-3d-flow/

Any suggestions or idea?

Do you think is too complicated VS stereo photogrammetry? 

Could you explain a bit more, do you want a measurement of length, or whole volume?

Like @wkcmark said, there are some simple solutions for measuring length fish, using stereo arrangements for example (2 cams looking at the same spot from slightly different angles). I also found this creative solution, using a single camera in a special acrylic case, that makes use of refraction indices. This, again, is for underwater systems.

If you could project two lasers at a known angle on the body of the animal like in exploration submarines, you could calculate the distance from the camera and measure the animal, although this would be a manual process.