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Comment by gok | Hacker News Reader

In pitch darkness, IR cameras can only see more than a visual light camera if you somehow had IR headlights that were more powerful than the visual headlights (they probably don't; that would blind other AVs just like high beams blind other drivers). It doesn't grant you the ability to see in the dark with infinite range. Lidar can sense shapes with more range, but at the cost of dramatically worse resolution and latency. It's conceivable the radar/lidar sensor caught the person in the left lane with a bike and decided that was a reasonable place for a person with a bike to be, then lost track of the person while she walked into the right lane (where the visual/IR system could not see her yet).

It's also entirely possible there was an egregious bug. This video doesn't really tell us much.

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Humans radiate in IR. A midrange FLIR can pick out a human against a cold background from miles away.

Long IR. No one is using that for AVs. (that might change after this incident!)

This is Arizona, however. The nights do cool down, but the concrete will still store a lot to heat.

Regardless, a human and metal bike should be very easily discernible with FLIR of adequate resolution.

A garden-variety uncooled LWIR camera from FLIR can see a difference of 0.05 degree. As long as the pedestrian isn’t wearing a thermal blanket from head to toe he/she can be seen.

Human beings radiate IR do they not? Silly question, of course they do. Perhaps not above an Arizona level of thermal background?

Thermal imaging and near-infrared imaging are not the same. Waymo/Uber/etc are not using thermography for their autonomous vehicles.

We see a nIR video of the driver. Those weird eyes everyone seems to have are the tell-tale sign of nIR as it interacts with the retina. So, we know that nIR sensors are being used in the interior, at least.

That said, Arizona in the summer is going to play havoc with lIR and thermography in erms of false positives and negatives. The sensor suite probably should be using lIR at night for this reason and the switching it off in the day. But given Uber's history, the lack of lIR reeks of cost-cutting.

I'm not an expert in IR or computer vision by any means, so take this with a grain of salt.

Air has such a low thermal mass that it doesn't measurably affect most IR sensors. Hot pavement could be a potential issue, but that shouldn't have a major effect on forward-facing sensors.

Besides, it's only March. Even Arizona isn't that hot yet.

> In pitch darkness, IR cameras can only see more than a visual light camera if you somehow had IR headlights

Did you ever use a thermal IR camera ? What you're saying only apply to cheap chi-com cheapo"IR" CCD (the ones you find in home security), not the FLIR/military-grade stuff.

Either way, the LIDAR must have seen her, and would have been emitting it’s own laser light.

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