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Comment by Someone

4 hours ago

> Since lidar has distance information and cameras do not, it was always a ridiculous idea by a certain company to use cameras only

Human eyes do not have distance information, either, but derive it well enough from spatial (by ‘comparing’ inputs from 2 eyes) or temporal parallax (by ‘comparing’ inputs from one eye at different points in time) to drive cars.

One can also argue that detecting absolute distance isn’t necessary to drive a car. Time to-contact may be more useful. Even only detecting “change in bearing” can be sufficient to avoid collision (https://eoceanic.com/sailing/tips/27/179/how_to_tell_if_you_...)

Having said that, LiDAR works better than vision in mild fog, and if it’s possible to add a decent absolute distance sensor for little extra cost, why wouldn’t you?

Human/animal vision uses way more than parallax to judge distances and bearings - it uses a world model that evolved over millions of years to model the environment. That's why we can get excellent 3D images from a 2D screen, and also why our depth perception can be easily tricked with objects of unexpected size. Put a human or animal in an abstract environment with no shadows and no familiar objects, and you'll see that depth perception based solely on parallax is actually very bad.

Human eyes are much better than cameras at dealing with dynamic range. They’re also attached to a super-computer which has been continuously trained for many years to determine distances and classify objects.

I don’t like the comparison between humans and humans. Humans don’t travel around at 100mph in packs of other humans. Why not use every sensor type at our disposal if it gives us more info to make decisions? Yes I understand it’s more complicated, but we figure stuff out.