> Lidar is great for distance representations, but requires a highly consistent and exact timing source. Just a small FYI: If you are doing time-of-flight mea

> Lidar is great for distance representations, but requires a highly consistent and exact timing source. Just a small FYI: If you are doing time-of-flight measurement, then yes. But many (not all) LIDARs out there don't do time-of-flight, because to get the resolution wanted or needed, you need to have an oscillator (and sensors for the return pulse) capable of many, many gigahertz (it can get absurd quickly if you want anything below a resolution of around 10 CMs). This isn't easy or cheap (the oscillator actually is fairly easy and cheap - it's the return sensor that needs a very fast rise time that is expensive and difficult, though such devices do exist - some all solid-state, like flash LIDAR). What many LIDAR sensors use (not sure about Velodyne) is actually using a kind of "doppler shift" of a laser modulated with a carrier wave. It still needs a high-speed multi-gigahertz oscillator to resolve small changes in distance, but everything else is fairly off-the-shelf and nothing real special. One downside of the method is that there is a discrepancy at farthest vs minimal distance measured due to ambiguity when comparing the received modulated beam to the outgoing modulated beam; you can't tell at such a point what the distance is (because both distances look the same).