Most of us first heard of these types of sensors with the Tesla self driving cars.
Again LiDAR or Light Detection and Ranging or Laser Imaging and Range Detection is a technology which has been around in some form since the Apollo 15 moon mission and is now very much the talk of the town.
Elon Musk has been very critical of this technology over the years for self driving cars and has called it the “devils errand” and a “crutch” as it is not apparently not reliable enough for road use.
But he is apparently testing it as of now May 2021 for the Y model.
But he has been quoted as being critical of both radar and LiDAR for self driving cars and saying this “We believe that a vision-only system is ultimately all that is needed for full autonomy.”
This got the company in some trouble in late May 2021 with the Consumer reports and the Insurance Institute for highway safety basically because Tesla stopped using radar and some of their vehicles in their safety systems.
Radars are usually in self driving cars to do things like forward collision warning, automatic emergency braking and emergency brake support, and lane departure warning.
Tesla reported that they were moving to a new system called ‘Tesla Vision” which will use cameras and the neural network and their autopilot and other things.
They do also use short range sonar sensors.
Now back to LiDAR. Its all about shooting a beam at some object and measuring the time it takes to come back.
Light emitted from the LiDAR is called pulse and the light reflected back from an object is called return.
Its been said that adding a LiDAR to a self driving car can add $10,000 to the cost.
But at least for hobby level robots you can add LiDAR technology to your creation for hundreds of dollars.
A company called DFRobot sells several types of very affordable LiDAR. One is a $40 TF mini-S LiDAR sensor and there are several RPI LiDARs which are full scanning sensors on a platform with a motor and sells for $100 and around $400.