Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Why Tesla removed radar and ultrasonic sensors [video]

youtube.com

Post reply on HN
Print view View original

71–80 of 483 posts

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

#71

Post by jbverschoor »

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…

It’s good enough for people, so all the info is there.

Doesn’t mean it’s better or easier

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

#72

Post by patrec »

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…

> 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 of business producing gadgets that, as an unintended side-effect, kill a lot of people (napkin math suggests above 2 milli-kills per car in the US), you will need to pick a point at which you say further fatality reduction is no longer justified given the economic cost of achieving it. Even if you are a pure altruist (if you go out of business, less safe cars will replace yours). Conversely, even if you are the embodiment of capitalist evil, risks to passengers will absolutely affect your bottom line and if are rational you will take them into consideration. Any meaningful criticism needs to be about the trade-offs they make, not that they make them or are loath to explicitly say so on camera.

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

#74

Post by lostsock »

petilon wrote: 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…

That video is from 2020, but Tesla didn't remove radar until 2021. Meaning that the crash occurred with radar still active, which I feel just backs up what Karpathy was saying.

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

#75

Post by JaggerJo »

This sucks for parking. It is simply (physically) not possible for the existing cameras to see the area directly in front of the car.

So how would this work for parking?

A: Add more cameras so there are no dead areas in front of the car

B: build a model in vector space when driving towards a parking spot and assume blind spots don't change. (still sucks)

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

#77

Post by api »

Nomentatus wrote: post #58
a-dub wrote: post #24

i'm not sure if i buy his argument that the "delta is not big enough." i have some experience with realtime ai systems and i've noticed something interesting about them. they have a non-smooth capability curve, where they can demonstrate proficiency in activities that in regular computer programs or people would imply a complete and continuous path of capability that has been mastered to achieve the demonstration, bu…

They do "fall off the edge of the world" a lot; but so do human neural networks; I've seen a bad crash as a result of a human simply pulling out of a driveway right in front of a motorcycle, 'cause they're rare. She had tagged the motorcycle as a bike while it was farther away, then boom. Her interpolation (while checking the other side) didn't work, and her averaging over uncertainty didn't work either because motor…

I see surprisingly little discussion of overall statistics on safety of self drive vs humans, and what I do see is often self reported by companies or by equally potentially biased sources in the media. I’ve searched many times and a straightforward stat seems hard to find.

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

#78

Post by Marazan »

Nomentatus wrote: post #54
petilon wrote: 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…

You're right to note the advantages of lidar and (narrow range of) contrast problem for cameras (they arent eyes.) This is why the Uber human driver shouldn't have trusted the machine at night, in particular. But you still have to address his system argument, which was that adding geegaws that added little would actually increase overall risks along the supply chain (plus maintenance) while distracting the team and a…

They cannot actually believe that.

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

#79

Post by bumby »

FreakLegion wrote: post #62
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…

> In other words, the results are better, but not enough to make up for the fact that 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. You may be right about the actual decision process Tesla went through, but Karpathy is right in principle. One of the first things he says is "there can be problems with…

There are other ways of optimizing for reliability, though, like redundancy in parallel or higher spec’d sensors. But that still gets back to the same issue where they are going to be concerned about cost.

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

#80

Post by NBJack »

Nomentatus wrote: post #57
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…

No, he precisely said that the difference Lidar made was tested, and the delta (difference made) was quite small; not enough to outweigh the downsides. Elon has noted that humans do well, and that's relevant, but that observation was also tested, re lidar.

Basically everything he said as a justification (sourcing, firmware, etc.) applies to every sufficiently advanced part of the vehicle. By that logic, they should not be using touchscreens on the center console, etc.
Post reply on HN