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Comment by kajecounterhack | Hacker News Reader

It's both. Your eyes have much better dynamic range and FPS than modern self driving systems & cameras. If you can reduce the amount of guessing your robot does (e.g. laser says _with certainty_ that you'll collide with an object ahead), you should do it.

Self-driving is still a robotics problem, and robots are probablistic operators with many component dependencies. If you have 3 99% reliable systems strung together running 24 hours a day, that's 43 minutes a day that it will be unreliable ((1 - .99^3)*1440). Multi-modality allows your systems to provide redundancy for one another and reduce the accumulating correlated errors.

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> Your eyes have much better dynamic range and FPS than modern self driving systems & cameras.

Eh, kind of...

https://youtu.be/HU6LfXNeQM4?t=1987

Check out this NOVA video on how limited your acute vision actually is. It is only by rapidly moving our eyes around that we have high quality vision. In the places you are not looking your brain is computing what it thinks is happening, not actually watching it.

It's only "kind of" if they compensate for the reduced specs. As the root commenter said, they don't compensate yet. It's just less safe in those situations.

Whether it's fine to be less safe in certain situations because it's safer overall is a different question.

> In the places you are not looking your brain is computing what it thinks is happening, not actually watching it.

The existence of peripheral vision disputes that pretty definitively, though.

I do recommend that you stop and watch the video first to understand better what's going on there....

I tried but it's not available in my country, sadly.

I should have said eyes+brain in combination have much better dynamic range and FPS perception than self driving systems. Point remains unchanged -- what sensor you use is tied to the computation you need to do. What you see is the sum of computation+sensor so it's impossible for sensor not to matter.

Tangential: event cameras work more like our eyes but aren't ready for AVs yet.

> Your eyes have much better dynamic range and FPS than modern self driving systems & cameras. If you can reduce the amount of guessing your robot does (e.g. laser says _with certainty_ that you'll collide with an object ahead), you should do it.

You could drive fine at 30fps on a regular monitor (SDR). More fps would help with aggressive/sporty driving of course.

Only if that monitor was hooked up to a camera that could dynamically adjust its gain to achieve best possible image contrast in everything from bright sunlight to moonlit night.

You’d also lose depth perception entirely, which can’t be good for your driving.

You can test this pretty easily, it's not like that model doesn't exist. Play your average driving videogame at 30fps in first-person mode. Crank up the brightness until you can barely see if you like. We do it just fine because the model exists in our head, not because there's some inherent perfection in our immediate sensing abilities.

> You could drive fine at 30fps on a regular monitor (SDR). More fps would help with aggressive/sporty driving of course.

What? This is preposterous.

Have you tried playing a shooter video game at 30 FPS? It's atrocious, you get rekt. There is a reason all gamers are getting 120 FPS and up.

30 FPS means 33 ms of latency. Driving on a highway, car moves over a meter before the camera even detects an obstacle. The display has it's own input lag, so does the operating system. Your total latency is going to be over 100ms, so the car will have travelled several meters. If a motorcyclist in front of you falls, you will feel the car crashing into his body before the image even appears on the screen.

I agree this is preposterous but one nit to pick: event loops on self driving cars are really that slow, and they must use very good behavior prediction + speculative reasoning to deal with scenarios like the one you described.

oh dear

There's plenty of FPS racing games that you can play just fine at 30FPS. Obviously more FPS is a better experience, but it's not like it becomes impossible to drive.

Also, if you truly are only a few meters behind a motorcyclist when driving at highway speeds, by definition you are being unsafe. The rule I learned in driving school was roughly 1 car length per 10mph of space, so you should be ~90 feet (~30 meters) away.

Finally, the average reaction time for people driving in real life is something like 3/4 of a second. 750ms to transition from accelerating to braking. A self-driving car being able to make decisions in the 100ms time frame is FAR superior.

Have you tried doing this in the dark? Have you tried spotting the little arrow in the green traffic light that says you can turn left, consistently, in your video feed even facing a low sun?

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