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ouster-lidar / ouster-sdk

Ouster, Inc. sample code
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Ambient and relfectivity data in Ouster Lidar #177

Closed ajay1606 closed 4 years ago

ajay1606 commented 4 years ago

Hello all, I recently started to work with OS 2 128 channel lidar, and better choice for LiDAR-based object perception. But I have a few questions related to ambient and reflectivity data from the sensor.

How the ambient and reflectivity calculated ? is there any research publication that describes the method.

Thanks in advance,

Regards, Ajay

dllu commented 4 years ago

As you may know, the lidar works by measuring the number of photons as a function of time (at the scale of nanoseconds). Once you have such a time series, the ambient, intensity, and range are related as shown in this diagram.

pic

Currently, the reflectivity is calculated assuming it is proportional to intensity * range^2, which is an approximation according to the inverse square law for Lambertian objects in the far field.

ajay1606 commented 4 years ago

@dllu Thank you so much for your quick response. Understood the concept.