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Current Tesla autopilot is sometimes blind to stopped cars

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Re: Current Tesla autopilot is sometimes blind to stopped cars

#42
post #30

Earlier quoted context omitted.

I don't the specifics of Tesla's radar implementation but what I have seen of the accidents usually seem like a textbook examples of incorrectly implemented clutter filtering. It's not an easy problem to solve in practice (re: cheaply), but known solutions have existed for decades.

The radar module in Teslas uses the same filtering strategy as most adaptive cruise control radar modules, which is "if relative velocity to object is nearly the opposite of the car's velocity, throw it out." It works pretty much as designed.

Right, sounds like they drop a bandpass filter on the down-converted Doppler spectrum. It's the simplest way to "solve" the clutter problem by just getting rid of everything stationary.

Re: Current Tesla autopilot is sometimes blind to stopped cars

#43

This has been true for a long time. Radar can't differentiate between a wall, a stopped car, or a dead skunk. Heck, it can get confused with a bridge's shadow on a bright day. Thus autopilot has to be configured to deal with these situations: stop or run into them. The vast majority of the situation you don't want the car to stop, as that will lead to a more dangerous situation and increase the chance of a collision.…

Can someone with more computer vision knowledge explain why we can't teach a machine learning algorithm to detect stationary cars. I have seen other Tesla demo videos where it clearly detects stationary cars. It seems ridiculous to say that it is a shortcoming of camera when our own two eyes do it.

It's not that it either always detects it or never detects it with video so much as that it doesn't detect it nearly as frequently as a human would. By contrast radar is pretty much always going to see things that aren't stationary.

Re: Current Tesla autopilot is sometimes blind to stopped cars

#44

Earlier quoted context omitted.

Can someone with more computer vision knowledge explain why we can't teach a machine learning algorithm to detect stationary cars. I have seen other Tesla demo videos where it clearly detects stationary cars. It seems ridiculous to say that it is a shortcoming of camera when our own two eyes do it.

It's not that it either always detects it or never detects it with video so much as that it doesn't detect it nearly as frequently as a human would. By contrast radar is pretty much always going to see things that aren't stationary.

But it would seem to me like that is just a matter of needing more training, or maybe more processing power.

At some point with enough training data it will detect a stopped car and react much more quickly than a human would. And even if it's not perfect, all it has to do is beat a human to be worthwhile.

Re: Current Tesla autopilot is sometimes blind to stopped cars

#46
post #26
post #17

Earlier quoted context omitted.

> Can any other Traffic-Aware Cruise Control (TACC) stop in such a case? (Real question, I don't know). I haven't found conclusive evidence, but the lack of news around other TACCs crashing into stationary objects is an indicator it might be a Autopilot specific issue. > My current understanding is that Tesla's TACC is the best on the market. Correct? Define best. It definitely has a lot of features few or no other s…

> I haven't found conclusive evidence, but the lack of news around other TACCs crashing into stationary objects is an indicator it might be a Autopilot specific issue. IMO, I think this may actually not be true. Due to Tesla's popularity, and the amount of investors that have stated that they were shorting TSLA, I do think that media have a tendency to report more news about such accidents just because a Tesla was in…

Tesla’s popularity? It is the twentieth-best-selling brand.

Re: Current Tesla autopilot is sometimes blind to stopped cars

#47
post #18

This has been true for a long time. Radar can't differentiate between a wall, a stopped car, or a dead skunk. Heck, it can get confused with a bridge's shadow on a bright day. Thus autopilot has to be configured to deal with these situations: stop or run into them. The vast majority of the situation you don't want the car to stop, as that will lead to a more dangerous situation and increase the chance of a collision.…

> Radar can't differentiate between a wall, a stopped car, or a dead skunk "Radar" absolutely can. What can't differentiate between these things is the radar in Teslas that was intended for use in adaptive cruise control. There are any number of not insanely expensive radars that could do this job perfectly fine. Tesla just decided to go "full self driving" with this rather bad radar because "humans can do it with vi…

[deleted]

Re: Current Tesla autopilot is sometimes blind to stopped cars

#48

Earlier quoted context omitted.

It's not that it either always detects it or never detects it with video so much as that it doesn't detect it nearly as frequently as a human would. By contrast radar is pretty much always going to see things that aren't stationary.

But it would seem to me like that is just a matter of needing more training, or maybe more processing power. At some point with enough training data it will detect a stopped car and react much more quickly than a human would. And even if it's not perfect, all it has to do is beat a human to be worthwhile.

It's not so easy, because you don't just have to detect stopped cars, you have to reject things which aren't stopped cars. False positive rejection appears to be something both Tesla and Uber are struggling with. (In the Arizona fatal accident, the Uber vehicle had Uber's own emergency braking system disabled because it was throwing up too many false positives.)

Re: Current Tesla autopilot is sometimes blind to stopped cars

#49

Can any other Traffic-Aware Cruise Control (TACC) stop in such a case? (Real question, I don't know). My current understanding is that Tesla's TACC is the best on the market. Correct?

Tesla's system is not the best: https://www.caranddriver.com/features/a24511826/safety-featu....

Re: Current Tesla autopilot is sometimes blind to stopped cars

#50
Tesla's system is not only not "autopilot" (it will happily plow into stationary vehicles), it's not even the best adaptive cruise control on the market for dealing with stationary vehicles: https://www.caranddriver.com/features/a24511826/safety-featu....

In a recent Car & Driver test, Subaru beat Tesla in every single scenario involving fast approach to a stationary/slow-moving target (although all collided with the target at closing speeds >= 50 mph).

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