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> 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?

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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.

> 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

That doesn’t require millions of years of evolution. We can ‘evolve’ it way faster on computers.

For an example, see https://depth-anything.github.io/.

I also think we don’t need good depth estimation to avoid collisions while walking around. The problem is scale-invariant except for the fact that deceleration is superlinear (doubling your speed more than doubles stopping distance), but at walking speed, that effect isn’t very large.

Decent depth estimation is needed for judging foot placement, but that’s at relatively close range.

At driving speed, that changes, but I think you can still get away with rough estimates.

(I’m not saying one shouldn’t use LiDAR, just arguing that we don’t know whether “LiDAR is necessary” is true. Yes, cameras cannot reproduce all aspects of human vision yet, but they also can surpass many aspects of human vision. Examples are resolution and field of view)

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.

> Human eyes do not have distance information

Single human eyes do resolve depth perception. Not as good as binocular vision, but you don't loose all depth perception of you lose an eye.

https://en.wikipedia.org/wiki/Monocular_vision

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.

Let me know when you have a camera package with human eye equivalency.

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