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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]

#31

Post by kfarr »

diskzero wrote: post #21
bekantan wrote: post #16

He explains it quite well: all necessary information is already in the pixel-space and adding more sensors slows team down more than it improves the system performance. My understanding is that major blockers are not in perception area anyways, would be great if someone with relevant experience could comment if this is indeed the case.

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…

Full on agreement. There are literally videos of Teslas smashing into stationary vehicles on the highway at night using only vision camera for FSD. No way any rational actor could claim the visible pixel space is sufficient in that scenario compared to LIDAR, Radar, etc

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

#32

Post by alsodumb »

diskzero wrote: post #21
bekantan wrote: post #16

He explains it quite well: all necessary information is already in the pixel-space and adding more sensors slows team down more than it improves the system performance. My understanding is that major blockers are not in perception area anyways, would be great if someone with relevant experience could comment if this is indeed the case.

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 successfully map everything needed from this information but I don't think Dr. Karpathy ever claimed that.

(I am not a principal engineer but a mere PhD student who argues daily with people on how RGB information is underappreciated and under utilized)

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

#33

Post by petilon »

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 cameras.

More importantly, expectations are higher when an automated system is driving the car. It is not sufficient if, in aggregate, self-driving cars have fewer accidents. If you lose a loved one in an accident where the accident could have been easily avoided if a human was driving, then you're not going to be mollified to hear that in aggregate, fewer people are being killed by self-driving cars! You'd be outraged to hear such a justification! The expectation therefore is that in each individual injury accident a human clearly could not have handled the situation any better. Self-driving cars have to be significantly better than humans to be accepted by society, and that means it has to have better-than-human levels of vision (which lidars provide).

[1] https://www.youtube.com/watch?v=X3hrKnv0dPQ

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

#34

Post by diskzero »

mongol wrote: post #30

What is it that makes Lidar so expensive? Is it something intrinsic to the technology that prevents costs from coming down?

A LIDAR sensor is a complex device with spinning motors, mirrors, lasers and more. Costs are coming down and less-expensive and more capable devices are coming to market. Once the price-points come way down, I wouldn't be surprised to see Tesla reconsider their decision to exclude them from their sensor platform.

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

#36

Post by threeseed »

ajross wrote: post #3
TheLoafOfBread wrote: post #2

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…

But the question at hand is system control, not locomotion! You're not asking the automation to walk (well, I mean someday we will, but Teslas have wheels), nor the aircraft to flap. We want the automation to do what a human pilot would do. And that works with eyes. No, I think this argument is largely correct. And frankly settled: anyone who's driven recent FSD beta versions knows very well that the cars "see just f…

> The LIDAR folks were wrong, basically

I think your mistake is thinking LiDAR exists to solve the happy day scenario. It doesn't.

Vision is sufficient for the majority of use cases. Where LiDAR comes into its own is in the edge cases because it almost guarantees accurate bounding box detection. Which is where vision is at its weakest.

So I want to know what does FSD do when it sees a billboard of a person or when it is seeing a new object for the first time.

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

#37

Post by alsodumb »

kfarr wrote: post #31
diskzero wrote: post #21

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…

Full on agreement. There are literally videos of Teslas smashing into stationary vehicles on the highway at night using only vision camera for FSD. No way any rational actor could claim the visible pixel space is sufficient in that scenario compared to LIDAR, Radar, etc

It's funny you use Radar as an example of 'good sensor' while it is well known that most or maybe almost all?) of the stationary vehicle accidents you're talking about happened because of Radars inability to detect a stationary obstacle.

On the other hand, RGB data does have that information, we use it everyday to avoid obstacles, even under foggy and rainy conditions (I'm no LIDAR expert but I know it sucks in rainy conditions)

I am not saying I support a vision only stack, but all I am saying is it is certainly possible to deploy a vision only stack in the future.

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

#38

Post by diskzero »

alsodumb wrote: post #32
diskzero wrote: post #21

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…

I'll agree with you that there are still techniques to be discovered.

I also agree that most humans manage to drive in challenging conditions, but their margins for error become slimmer and slimmer. I personally want my autonomous robot vehicle to be way more efficient and safer than the best human operator and also able to deal with conditions that any sane human would pull to the side of the road when encountering.

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

#39

Post by threeseed »

CharlesW wrote: post #11

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…

It was an ominous answer.

We really should be focusing on what is the best solution and trying to solve price issues through existing techniques e.g. economies of scale, competition, miniaturisation. Instead they are trying to build whatever solution they can that fits in a pre-defined cost window.

Except this isn't a new phone or sneakers we are trying to take to market it's something that will directly impact people's lives.

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

#40

Post by threeseed »

ajross wrote: post #14
elteto wrote: post #6

Earlier quoted context omitted.

> The LIDAR folks were wrong, basically. This is far, far from settled at this point.

No, it's over. Look, the LIDAR value proposition was necessarily "Yes, we're outrageously expensive and involve major tradeoffs in physical design of the vehicle, but vision can simply never do what we do". And... vision does. It does, every day. On hundreds of thousands of cars. In point of fact FSD beta vehicles are out there every day in environments where LIDAR has never been deployed, nor likely ever tested. And…

> And we're not seeing clear "it can't do this" failures. Anywhere

Do you have evidence of the number of accidents, disengagements etc by region ?

Because you're making awfully definitive statements about FSD safety.

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