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Why Tesla removed radar and ultrasonic sensors [video]

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Re: Why Tesla removed radar and ultrasonic sensors [video]

#81

This whole question about the vision boils down to "humans don't need it so cars should not need it too" the problem with this statement is that humans does not have wheels to move around, they have legs, but wheels are ridiculously simple compared to 4 legs tapping 160km/h on a highway. Same for birds - they also does not need jet engines to fly around, but imagine Airbus A380 flapping its wings and what kind of com…

> "humans don't need it so cars should not need it too"

I think of parking and I'm reminded of "the camry dent"

https://duckduckgo.com/?q=the+camry+dent&iax=images&ia=image...

Re: Why Tesla removed radar and ultrasonic sensors [video]

#82

Earlier quoted context omitted.

I think one should distinguish between 'all necessary information is already in the pixel-space' vs 'we already know how to extract all the information needed from pixel-space' The fact that (most) humans manage to drive around safely and successfully in current roads proves that the information needed exists in the pixel-space (not just current image, but say current + history). We don't yet have stacks that can suc…

> The fact that (most) humans manage to drive around safely and successfully in current roads proves that the information needed exists in the pixel-space But that doesn't mean that it translates to a car. We constantly move our 576MP resolution eyes in multiple orientations in order to visualise a scene and focus on the most important areas. Cars have fixed, low-quality cameras. We then interpret this data using the…

> 576MP

Actually our eyes are more like 8MP: https://www.picturecorrect.com/what-is-the-resolution-of-the...

Perhaps higher synthetic resolution from moving our eyes about, or perhaps that is meaningless.

Re: Why Tesla removed radar and ultrasonic sensors [video]

#83

Earlier quoted context omitted.

I am a principal engineer for a major autonomous vehicle company. You can break this statement down into two components: Adding more sensors slows his team now more than it improves system performance I'll take his word on this. It is a lot of work to incorporate multiple sensors. All necessary information is already in the pixel-space. I hate to disagree with someone as distinguished as Karpathy, but this is simply…

I think one should distinguish between 'all necessary information is already in the pixel-space' vs 'we already know how to extract all the information needed from pixel-space' The fact that (most) humans manage to drive around safely and successfully in current roads proves that the information needed exists in the pixel-space (not just current image, but say current + history). We don't yet have stacks that can suc…

bleh. auto accidents are the #1 preventable cause of death for kids:

https://en.wikipedia.org/wiki/Preventable_causes_of_death#Am...

Re: Why Tesla removed radar and ultrasonic sensors [video]

#84
post #33

I didn't find his answers particularly convincing. His answer focused on costs mainly, and how "the best part is no part". We have already seen multiple accidents caused by camera's limitations [1] which would not have happened if Tesla used Lidars. Cameras have poor dynamic range and can be easily blinded by bright surfaces. While it is true that humans do fine with only eyes, our eyes are significantly better than…

> It is not sufficient if, in aggregate, self-driving cars have fewer accidents

It would be sufficient if it would be the case. With actual proof.

Reality is that in limited abstract situations, self driving card maybe have some advantages. But, that is all that we can claim. And when self driving fails, somehow human is always the cause.

Re: Why Tesla removed radar and ultrasonic sensors [video]

#85
post #72

I thought it was telling that Andrej immediately "reframed" the question because Lex asked the "wrong question". This is a classic evasion technique one learns from experience and/or media training. Lex's comment immediately after was a clever and gentle dig at Andrej's response. It seemed like all the "full cost" negatives Andrej mentioned were related to Tesla's ability to execute, and not what would actually produ…

> I thought it was telling that Andrej immediately "reframed" the question because Lex asked the "wrong question". This is a classic evasion technique I agree with this assessment. However: > Telsa can't support additional sensors without incurring a prohibitive amount of additional risk to Tesla. Risk to passengers doesn't appear to be a consideration. This is a stupidifying take. Of course when you work in a line o…

[deleted]

Re: Why Tesla removed radar and ultrasonic sensors [video]

#86
post #4

So the key question is how much of an improvement does radar/sensors/etc give you over just using computer vision?

A better "answer" might be to make them an option and let the market decide.

For many (MANY) years airbags were fought by the auto industry even though people wanted them.

Re: Why Tesla removed radar and ultrasonic sensors [video]

#87
post #33

I didn't find his answers particularly convincing. His answer focused on costs mainly, and how "the best part is no part". We have already seen multiple accidents caused by camera's limitations [1] which would not have happened if Tesla used Lidars. Cameras have poor dynamic range and can be easily blinded by bright surfaces. While it is true that humans do fine with only eyes, our eyes are significantly better than…

> While it is true that humans do fine with only eyes, our eyes are significantly better than cameras.

They also have better failure modes and a really sophisticated error management system. They are susceptible to optical illusions, though.

> It is not sufficient if, in aggregate, self-driving cars have fewer accidents.

This is the incorrect analysis anyways. This was always going to be true because a large portion of accidents are single vehicle accidents where the driver was at fault for the crash. Usually due to speeding, alcohol, youth, or a combination of them.

If they didn't have fewer accidents then something is very very wrong with the entire idea. Which may very well be the outcome here. Looking at multi-vehicle accidents where there was no fault of the driver who died, it's not clear that an automated system driving the car would have saved them.

Roads are built right next to cliffs and bodies of water. Semi trucks can completely destroy your vehicle in an instant. Large accidents on snowy or foggy highways happen. Drunk drivers exist and sometimes literally do come out of nowhere, a pickup truck moving at 60mph has enough energy to knock a firetruck onto it's side if you hit it side-on and freeway ramps dump out right onto residential streets. Parts fail, floormats get stuck, people don't wear their seatbelts, and you can get a license to ride on a motorcycle if you want.

It's a guess based on the research I've done, but my expectation is around 20% of fatal accidents can in some way be prevented by automation. You'd honestly prevent more fatalities by putting an ignition interlock on everyone's vehicle or building real barriers between traffic and pedestrians.

Re: Why Tesla removed radar and ultrasonic sensors [video]

#88

I thought it was telling that Andrej immediately "reframed" the question because Lex asked the "wrong question". This is a classic evasion technique one learns from experience and/or media training. Lex's comment immediately after was a clever and gentle dig at Andrej's response. It seemed like all the "full cost" negatives Andrej mentioned were related to Tesla's ability to execute, and not what would actually produ…

That was hilarious. Basically (unless this needs a reframing/realignment/repositioning/reorienting): Q: "are less sensors less safe/effective?" A: "well more sensors are costly to the organization and add more tech debt so safety is orthogonal and not worth answering".

The video has a more reasonable answer.

The sensors are unreliable and expensive in terms of R&D. Having marginal parts which takes money from a finite R&D budget can easily result in a worse product. “They contribute noise and entropy into everything.” … “you’re investing fully into that [vision] and you can make that extremely good. You only have a finite amount of spend of focus across different facets of the system.”

His standpoint can be summed up as “I think some of the other companies are going to drop it.” Which would be really interesting if true.

Re: Why Tesla removed radar and ultrasonic sensors [video]

#89
I remember watching an interview with George Hotz when Comma.ai was young, where he essentially said this as a critique of Tesla. He's a bit of a showman and likes to invite a little controversy when he says things, but I found myself agreeing with his point. It's not surprising to see such a practical company like Tesla face the facts about all these sensors eventually.

Re: Why Tesla removed radar and ultrasonic sensors [video]

#90
post #33

I didn't find his answers particularly convincing. His answer focused on costs mainly, and how "the best part is no part". We have already seen multiple accidents caused by camera's limitations [1] which would not have happened if Tesla used Lidars. Cameras have poor dynamic range and can be easily blinded by bright surfaces. While it is true that humans do fine with only eyes, our eyes are significantly better than…

The problem with self-driving is that it is based on data, but the environment may change. See e.g. the case where Tesla thinks that firetrucks are roads.

So if fashion changes, pedestrians may suddenly look like road too, as just an example.

Another problem is that state-of-the-art classification networks have an accuracy in the 90% range. Given that a car has to take hundreds of decisions in a single ride, then even if the accuracy was 99%, you see that error rate simply gets too high.

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