LIDAR is all the range*. It's one of the fundamental sensing technologies of autonomous vehicles. It gives a system the ability to see how far away things are 360 degrees around it.

We used the Garmin LIDAR range finder in another guide. It works by sending out a pulse of modulated laser light which bounces off whatever it's aimed at and is read by an optical receiver. The time that takes is a measure of distance to the surface it bounced off of. While being very cool and very effective technology, it just looks in one direction. You could mount it on a stepper motor and repeatedly rotate and take a reading. Or you could use a 360 degree LIDAR system like the RPLIDAR from Slamtec.

_{* See what I did there?}

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