Why Tesla removed radar and ultrasonic sensors [video] • Hacker News Board

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

#211

Post by JumpCrisscross » Mon, Oct 31, 2022, 3:08 AM UTC

xodjmk wrote: post #202

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…

The majority of comments surrounding stereo-camera/lidar questions have a ridiculously simplified idea of the problem. It's obviously the case that 'more sensor good, less sensor bad'. This is frankenstein's monster level technical analysis. Why don't the majority of large-brained animals have many eyes, and many different antannea appendages processing an array of diverse sensory input? You don't just automatically…

> Why don't the majority of large-brained animals have many eyes

Because of the cost of additional eyes. If Tesla is optimizing for cost against safety, that's sort of the point.

I don't believe that's totally the case. Andrej later makes a better argument regarding limited R&D bandwidth, noise and entropy. But the "I would almost reframe the question" evasion was disconcerting. It's a textbook media trained tactic for avoiding a question to which you have no good answer. That it was deployed here badly against a skilled interviewer such that it backfired is a valid observation.

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

#212

Post by touch_abs » Mon, Oct 31, 2022, 3:10 AM UTC

api wrote: post #77

Nomentatus wrote: post #58

Earlier quoted context omitted.

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.

There isnt really a way to gather the data free from a manufacturer, every current self-drive mode has limited operating scenarios, if you want to record an incident you first need the manufacturer to confirm that it was operating, and that it was one of the intended use cases.

Companies are less interested in safety vs a human to begin with, they have a emphasis on not causing any accident they are culpable for.

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

#213

Post by xodjmk » Mon, Oct 31, 2022, 3:11 AM UTC

YZF wrote: post #113

aeternum wrote: post #93

Earlier quoted context omitted.

Lack of focus is a major problem for companies and we all know that tech debt leads to increased bug counts. Team focus on vision which is by far the highest accuracy and bandwidth sensor allows for a faster rate of safety innovation given a constant team size.

Tesla's cameras often get blocked by rain or blinded by the sun or not see that well in the dark. It's really hard to imagine those cameras replacing the ultrasonic sensors which do a pretty good job at telling you where you are when you're parking etc. I can't see how the camera is going to detect an object at pitch dark and estimate the distance to it better than an ultrasonic sensor. But hey, if people ding their…

You are greatly overestimating the functionality of the sensors, and underestimating the importance of the rest of the system. Sensors are important, but the majority of the work, effort and expense is involved with post-sensor processing. You can't just bolt a 'Lidar' on to the car and improve quality of results. Andrej and other engineers working on these problems are telling everyone the same story. The perfect solution is not obvious to anyone, and they have chosen one path. Engineers aren't trying to scam people out of a few dollars so they can weasel out of making high quality technology. This has Nothing to do with cost-cutting.

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

#214

Post by JumpCrisscross » Mon, Oct 31, 2022, 3:12 AM UTC

dmix wrote: post #150

a1369209993 wrote: post #121

Earlier quoted context omitted.

> Having marginal parts which takes money from a finite R&D budget can easily result in a worse product. "Less sensors can be more safe/effective if that allows us to focus on making effective use of the sensor information we do have, which is the result we're aiming for with this descision." would be a reasonable answer (if true), but that doesn't seem like a fair interpretation of what he actually said.

Isn’t that his point though? Where exactly is he not saying that? I listened to his answer three times and I’m not able to come up with a different interpretation than that.

> Isn’t that his point though? Where exactly is he not saying that?

Andrej eventually gets to it. But his first response was to evade. Lex is a skilled interviewer. By not letting him wriggle out of a difficult question we eventually got a substantive answer. But Andrej's first instinct was to evade. That's notable.

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

#215

Post by wonnage » Mon, Oct 31, 2022, 3:13 AM UTC

minhazm wrote: post #122

threeseed wrote: post #39

Earlier quoted context omitted.

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 peopl…

There's an opportunity cost trying to get to the best solution. What about all of the people that die in the mean time while we delay rolling out something due to it not being perfect? Just doing some googling the Waymo stack is estimated to cost somewhere in the range of $50-100k, not including the car. A better solution that no one can afford is no solution at all. Ultimately the only requirement is that the system…

Wonder if this is a strong argument for public transit too. While self driving cars are developed let make every effort to figure out if we can get people to take the existing self driving trains and subways…

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

#216

Post by BeefWellington » Mon, Oct 31, 2022, 3:13 AM UTC

YZF wrote: post #132

FreakLegion wrote: post #62

Earlier quoted context omitted.

> 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…

Taking his point to the extreme why use 8 cameras? just use 4? 1? One photo-diode? Cameras can also fail at run-time there can (and is) be variability in how they're mounted, in the lenses, in the sensors. They can get blinded or not get enough light. Their cabling can fail random components can fail. Tesla has claimed that vision outperforms vision+radar but anecdotal reports don't seem to support that conclusion. I…

I would also add that Tesla's sensor systems, while perhaps higher quality, are not exactly new ideas. In one form or other laser/radar-based systems have been in cars going back to the 90s for early collision avoidance, automatic cruise control, etc.[1] Longer in other applications.

At least one study seems to suggest those sensors when deployed in automatic emergency braking systems do have a measurable impact on collisions.[2]

Let's say the failure rate on the sensors was 1 in 100 (I'd be shocked if that many were defective). That means 99 other Teslas are using mutli-sensor systems and not driving with degraded capabilities. It's an asinine claim that doesn't pass basic logic tests. The only way they weren't a substantial improvement is if Tesla's measurements were conducted in only the absolute most ideal conditions for cameras and no other scenarios.

[1]: https://en.wikipedia.org/wiki/Adaptive_cruise_control#Histor...

[2]: https://www.forbes.com/advisor/car-insurance/vehicle-safety-...

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

#217

Post by AlotOfReading » Mon, Oct 31, 2022, 3:14 AM UTC

dmix wrote: post #173

dreamcompiler wrote: post #154

It's obviously a stupid decision to remove a direct source of range data (radar and ultrasound) in favor of an indirect one (vision). But on second thought this doesn't bother me that much because Tesla FSD is absolute garbage even with radar (and I don't think Tesla will get away with selling the FSD snake oil for much longer), so if vision-only is good enough for the base-level lane-keeping autopilot functionality…

Even though the risks are high the outcomes will always keep them honest. Whether they like it or not. This isn't like Facebook continually releasing a product that sucks but people will use anyway. Tesla is constantly working against the clock and everything they do has real world consequences. There are multiple gov agencies watching over it at all times. Of course there's lots of people with far higher risk tolera…

Outcomes have to be truly and utterly fucked for "new" types of problems to be noticed in the automotive industry. Take the Toyota Unintended Acceleration case, where completely negligent software quality took over a decade and at least 89 lives to be noticed and (partially) rectified.

Regulators have keen noses for very particular types of issues and rely heavily on manufacturer judgements on a lot of the rest. Issues that aren't in any of those fairly narrow categories need to be extremely public or extremely egregious to attract their notice.

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

#218

Post by JumpCrisscross » Mon, Oct 31, 2022, 3:14 AM UTC

ion_fury wrote: post #95

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…

lex's comment did not strike me as a dig. i am actually concerned by your comment because it makes me wonder if i am missing other things too? it just doesnt seem like a dig. it seems like he thought of something funny and wanted to share it. am i alone in this? and also i dont understand your assertion that it was some kind of cynical maneuver to re-frame the question. he could have also said "yes, more sensors are…

> did not strike me as a dig

It wasn't a dig. It was calling out a bullshit move that, in my opinion, Andrej deployed out of panic more than strategically. (My evidence for this being Andrej eventually gave a good answer.)

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

#219

Post by eightysixfour » Mon, Oct 31, 2022, 3:17 AM UTC

RC_ITR wrote: post #208

stefan_ wrote: post #141

Earlier quoted context omitted.

This thread is unhelpfully mixing radar and ultrasonic sensors. Ultrasonic sensors, as your video explains, are primarily used as a parking aid; they are tuned for too low a distance to be helpful in just about any kind of driving scenario at speed. Meanwhile, radar is the principal sensor used in systems like automatic emergency braking across the industry. It has no intersection with any of the parking stuff becaus…

The first famous autopilot crash was because a white semi-truck was washed out by the sun and confused for an overhead sign. That's literally trivial for a car with radar to detect. Amazing how people talk about stuff they have no idea about when it comes to Tesla.

Not a fan of Tesla removing the sensors but a vehicle on a highway that isn’t moving the same direction as the car is not “trivial” with radar. No AEBs that use radar look for completely stopped objects after a certain speed because the number of false positives is so high.

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

#220

Post by sumedh » Mon, Oct 31, 2022, 3:18 AM UTC

YZF wrote: post #113

aeternum wrote: post #93

Earlier quoted context omitted.

Lack of focus is a major problem for companies and we all know that tech debt leads to increased bug counts. Team focus on vision which is by far the highest accuracy and bandwidth sensor allows for a faster rate of safety innovation given a constant team size.

Tesla's cameras often get blocked by rain or blinded by the sun or not see that well in the dark. It's really hard to imagine those cameras replacing the ultrasonic sensors which do a pretty good job at telling you where you are when you're parking etc. I can't see how the camera is going to detect an object at pitch dark and estimate the distance to it better than an ultrasonic sensor. But hey, if people ding their…

> I can't see how the camera is going to detect an object at pitch dark

Lights?