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> from totally normal to batshit insane

Self driving cars don’t put that much emphasis on street signs, their not for example going to drive into a brick wall because of an arrow.

Alter speed limit signs in front of a speed trap might hit a lot of people but their unlikely to try and take a sharp turn at 70MPH or anything.

> Self driving cars don’t put that much emphasis on street signs,

They have to. Even the most accurate maps of speed limits have flaws and cannot adapt to dynamic limits. I'm pretty sure that if car makers could avoid the trouble of parsing signs, the would do so.

> their not for example going to drive into a brick wall because of an arrow.

Teslas first driver death was due to the car not recognizing a white truck. It would be easy to add a fake increase in speed limit, just before a white enough wall, so that the car would not be able to brake in time once the LIDAR picks the obstacle up. To the casual observer it would look like the car just decided to accelerate into a wall.

Tesla cars don’t have LiDAR right? That’s why they are so susceptible to this problem. Visual sensors only.

It feels borderline irresponsible that Tesla is visual only. Why not collect another datapoint in the form of lidar? It's human lives at stake, don't tell me lidar is too costly: M robot vacuum uses Lidar and the thing cost 1/10th the price of putting leather seats on most cars today. It's excellent, the vacuum has no issues with my white walls and it paints beautiful maps of my apartment. I'd strap myself to it and go around town right now if it could only support the weight.

LIDAR surely wouldn't work very well in rain though? Same problem with the RADAR - can't see RADAR transparent objects.

I kind of understand where they're coming from: a sensor where under some conditions you have to totally disregard all its input is a really bad sensor to have because your model will get disproportionately good using the "good" input, and then you're still left with "and in a medium drizzle we need to also work off optics only".

Not really though right? Sensor fusion is used, and it’s a generally solved problem. We do the same thing - we have sound, touch (which can also pick up changes in air pressure, humidity, temperature, wind), visual, and internal model/balance.

We’ve evolved to do that because it’s necessary for survival - sometimes we get dust in our eyes, or there is glare, or it’s too dark to see and we don’t have a light, or we’re picking up on a impending problem with something around a corner (a loud fight, or whistling wind), etc.

If visual sensors and LiDAR suck in the rain, radar is great. If radar sucks in crowded road or RF noisy environments, that’s when LiDAR or visual sensors are awesome.

Even on the road this is true - rumble strips, mechanical noise, shaking, etc.

How though? If LIDAR is your only depth ranging input, then rain means it's gone - there's nothing to fuse.

RADAR isn't an adequate replacement as severally crashes have demonstrated - it can't see non metallic objects.

That's the problem I think you're glossing over: under a whole bunch of circumstances your model is operating with out an entire sense.

I take it you have no idea how sensor fusion works?

Sensor fusion weighs inputs from multiple sensors, determining (roughly) which ones are ‘more wrong’ and ignoring them, to various degrees.

LiDAR also doesn’t just ‘not work’ at all in rain, it degrades as it gets heavier until it doesn’t work. Like vision, etc. Radar also can pick up non metallic objects, and does all the time - including geese, humans, clouds, etc, depending on frequency, and there are variable frequency radars out there that can do all sorts of cool stuff, including frequency sweeping, so it’s not just going to ‘miss’ something. There are of course issues like multipathing. But that is why sensor fusion, and similar techniques.

All of this adds up to something much more accurate and less prone to failure than basic vision, which is what Tesla is running now. It also costs more.

> not for example going to drive into a brick wall because of an arrow.

If the self driving car misinterpreted a "NO SWIMMING" sign to a "MUST TURN RIGHT" sign, I assume it's going to take the turn and drive into a lake?

Why would the car follow a sign instead of Google maps?

Because maps can always be out of date?

It's common that due to construction, temporary road signs are placed to re-route traffic. It would be a disaster if the self driving car simply ignores them because they are not on the map, I assume?

> drive into a brick wall because of an arrow.

I honestly would push back on this, the car is more likely to recognize the arrows/lane markers and might not understand a brick wall - from what I can tell from watching the FSD ride-alongs, if they car doesn’t understand something it just ignores it.

> Things like this are, in my opinion, also exactly why people put the bar of trust so high for autonomous vehicles: They might fail in ways totally opaque to us. You can at least somewhat estimate what a person might do [0]; for autonomous cars, this is hard or even impossible.

This is the subject of the story Car Wars by Cory Doctorow - https://web.archive.org/web/20170105065118/http://this.deaki...

> But most of them are easy to spot

I mean, walking upto a stop sign dangling a projector on a stick is pretty damn easy to notice.

It's also much easier to just hold up a bogus actual sign than to go through this mess, and it would be highly illegal as well.

Could etch the pattern onto a mirror that reflects sunlight onto the sign at the chosen time of day that your chosen victim drives by everyday

(Disclaimer, I doubt this works because the adversarial image is probably based on a single frame, not the actual object in context)