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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]

#121

Post by a1369209993 »

Retric wrote: post #88
flashgordon wrote: post #51

Earlier quoted context omitted.

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 syst…

> 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.

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

#122

Post by minhazm »

threeseed wrote: post #39
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 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 is safer than humans by some margin that people are comfortable with buying such a system. If that amount is even as little as 2x safer than humans, we still have a moral obligation to roll that out even if we could be 5x safer if we had another $50k worth of sensors and processors on the car.

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

#123

Post by paulryanrogers »

Nomentatus wrote: post #103
NBJack wrote: post #80

Earlier quoted context omitted.

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.

If the safety delta was low after removing them, as 'tis with Lidar, absolutely.

It's also possible their LIDAR implementation was poor. Waymo uses LIDAR and has fewer incidents per mile.

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

#124

Post by aeternum »

petilon wrote: post #108
aeternum wrote: post #96

Earlier quoted context omitted.

The dynamic range is the reason Tesla know counts photons rather than use traditional camera processing. They basically remove the concept of exposure entirely and simply pass the sensor photon counts to the neural net. This approach not only simpler as it removes photo processing/encoding but the result is that the NN can operate with a very high dynamic range similar to the human eye and in many cases can be sensit…

But it doesn't appear to be helping. Here's an example accident where depth data from Lidar would have helped: "Tesla later said that during the crash, Autopilot’s camera could not distinguish between the white truck and the bright sky." https://www.nytimes.com/2021/12/06/technology/tesla-autopilo...

The crash you referenced occurred in 2016 when they were using radar on the cars and I don't believe they were yet using raw photon counts nor did the NN have any voxel-based memory as it does now.

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

#125

Post by Nomentatus »

Marazan wrote: post #78
Nomentatus wrote: post #54

Earlier quoted context omitted.

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.

There's a new article showing up just today at HN detailing more issues securing supply lines (for libraries and much more) re software; it's a deep problem, not a non-existant problem. But it doesn't have to be malicious actors at work. SpaceX lost a rocket because a supplier's product wasn't built to spec. SpaceX makes that part themselves now, and highly favors vertical integration, which just means making your own sh*t. Just maintaining documentation is a bear. There's another article on HN today detailing an Air Astana near crash because of "improvement" maintenance changes (with poor documentaion) that went very badly wrong.

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

#126

Post by Gigachad »

mensetmanusman wrote: post #117
petilon wrote: post #108

Earlier quoted context omitted.

But it doesn't appear to be helping. Here's an example accident where depth data from Lidar would have helped: "Tesla later said that during the crash, Autopilot’s camera could not distinguish between the white truck and the bright sky." https://www.nytimes.com/2021/12/06/technology/tesla-autopilo...

Humanity doesn’t know how to solve this yet, so it’s hard to say whether it is helping or not.

We already have the solution. LiDAR.

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

#127

Post by syntaxing »

aeternum wrote: post #93
flashgordon wrote: post #51

Earlier quoted context omitted.

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".

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.

Uhh highest accuracy and bandwidth for what? You can have a camera that can see piece of steak at 100K resolution at 1000 FPS but doesn’t mean you can use a camera to replace a thermometer. Blows my mind how people eat up that cameras can replace every sensor in existence without even entertaining basic physics. ML is not omnipotent.

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

#128

Post by 113245 »

AtlasBarfed wrote: post #9
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…

soooo... you're agreeeing that non-vision isn't necessary since the control domain is so much simpler? I personally think they should use as much data inputs as possible: radar, IR, LIDAR, mesh networks, fixed route information. Where tesla went particularly wrong IMO is ignoring some sort of route-based chunk information which is how humans navigate. IIRC Elon said something to the effect of just having an algorithm…

The Tesla AI day videos [1] go into some detail about this. They use multiple networks that are dedicated to specific tasks.

[1]https://www.youtube.com/watch?v=j0z4FweCy4M (2021), https://www.youtube.com/watch?v=ODSJsviD_SU (2022)

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

#129

Post by jandrese »

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…

> While it is true that humans do fine with only eyes

We do not. Humans are terrible at driving. Traffic accidents are one of the leading causes of death in the developed world. Billions of dollars of property damage occur every year because humans are not up to the task. A self driving system that is as safe as an average human driver would be an absolute failure.

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

#130

Post by jiggawatts »

pclmulqdq wrote: post #27
6stringmerc wrote: post #22

Earlier quoted context omitted.

I have driven in extreme rain flash flood conditions in north Texas and I consider this a specific challenge, natural, that would defeat his system.

Any amount of snow would do this too. It severely reduces the color space of road features.

Tesla cameras are not RGB, they're WWWR (white-white-white-red). Essentially they have a Bayer array, but only for 1 red pixel out of four, the other three are black & white. I believe that the W pixels aren't homogenous either, there is some design aspect that enables them to cover a wider range of intensities so that they can handle both darkness and full sunlight.
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