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

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

#461

Post by pmarreck » Tue, Nov 01, 2022, 1:11 AM UTC

n0tth3dro1ds wrote: post #240

pmarreck wrote: post #114

Earlier quoted context omitted.

Two thoughts: 1) He's not touching on the software cost of integrating different sensor data into the same trained machine learning model; it is likely far simpler to just stick to stereoscopic vision data (the same thing the human genome decided!) 2) That said, it seems at least theoretically advantageous to have a sensory system that exceeds that which humans are limited to; things like LIDAR can work in complete d…

>it is likely far simpler to just stick to stereoscopic vision data (the same thing the human genome decided!) There’s a lot more to perception while driving than just stereoscopic vision. First, your stereoscopic “cameras” (eyes) are mounted in free-rotating sockets, which are themselves mounted in a rotating and swiveling base (your head/neck). Your eyes can do rapid single-point autofocus better than any existing…

Good points. What did your temporary deafness end up being, if I may ask?

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

#462

Post by pmarreck » Tue, Nov 01, 2022, 1:13 AM UTC

jquery wrote: post #200

sfifs wrote: post #138

Earlier quoted context omitted.

> likely far simpler to just stick to stereoscopic vision data (the same thing the human genome decided!) Yeah and till we had reliable and powerful artificial lighting, it was highly unsafe to journey in low visibility/ darkness. We used to finish journeys when darkness fell. Animals that do require precise movement in low visibility (bats, dolphins) conditions often evolved ultrasound solutions. So should we licens…

Excellent points, I didn't think about the fact that even evolution couldn't come up with a vision system that works as well in the dark as it works in the daytime.

Well actually, the human vision system at night, while not as good as cats and perhaps dogs, is still much greater than any camera we've come up with thus far, I read something that claimed we can actually detect individual photons hitting our retina, once we are adapted to the darkness

https://www.science.org/content/article/human-eye-can-detect...

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

#463

Post by n0tth3dro1ds » Tue, Nov 01, 2022, 1:19 AM UTC

pmarreck wrote: post #461

n0tth3dro1ds wrote: post #240

Earlier quoted context omitted.

>it is likely far simpler to just stick to stereoscopic vision data (the same thing the human genome decided!) There’s a lot more to perception while driving than just stereoscopic vision. First, your stereoscopic “cameras” (eyes) are mounted in free-rotating sockets, which are themselves mounted in a rotating and swiveling base (your head/neck). Your eyes can do rapid single-point autofocus better than any existing…

Good points. What did your temporary deafness end up being, if I may ask?

Water and ear wax. I went swimming the day before.

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

#464

Post by 9935c101ab17a66 » Tue, Nov 01, 2022, 1:57 AM UTC

dmix wrote: post #227

AlotOfReading wrote: post #217

Earlier quoted context omitted.

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. Issu…

I’ve read into the Toyota case in the past and it doesn’t seem like it was that obvious of a regulatory failure, where you could come to such a conclusion. Did I miss some good article covering it? Because everything I’ve read with the benefit of retrospect has been pretty critical of a lot the alleged ‘cases’ reported in that 89 number. Are you sure that’s the example you want to use for pre-emptive regulatory failu…

Somewhat related: I read into the case about a year ago and was shocked at how little coverage there is. There isn’t even a dedicated Wikipedia article — there’s only a one paragraph summary on the general article “Sudden Unintended acceleration” that covers all causes and prominent cases. 89 people died, and Toyota knew about the problem for years! Not only did they not do anything, they hid it. I just don’t get why more people didn’t talk about it. It’s not like it all happened in the distant past — Toyota was fined by Justice dept in 2014!

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

#465

Post by 9935c101ab17a66 » Tue, Nov 01, 2022, 2:00 AM UTC

mgoetzke wrote: post #349

hbarka wrote: post #260

Intuition + other examples tell you that radar and ultrasonic sensors work. Why do we twist ourselves to believe otherwise? Elon removed the radar and ultrasonics for the simple fact that its supply chain logjam was screwing up the manufacturing schedule. They also realized that the profit margin can be sustained in an inflationary environment by simply removing these parts [1]. “Oh, we were going to remove them anyw…

So all those engineers are lying when they talk about this topic ?

Uh, which engineers are you referring to?

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

#466

Post by seanmcdirmid » Tue, Nov 01, 2022, 2:40 AM UTC

ClumsyPilot wrote: post #347

seanmcdirmid wrote: post #236

Earlier quoted context omitted.

It is a hard question to answer. It’s like asking if more programmers on a project will allow it to be completed faster with higher quality. Ya, theoretically they could, in practice not likely. More sensors are like more programmers, theoretically they can be safer and more effective, but in practice they won’t be. Sensor fusion is as hard a problem as scaling up a software team.

> More sensors are like more programmers More programmers are like having more testicles, theoretically they should enable you to have more kids, but in practice bootleneck are elsewhere. Both your and my reasoning by comparison is equally valid

That isn't it though. It isn't like pumping a baby out in 1 month using 9 women. No, the problem is the fusion of too much information that varies substantially. They have completely different views of the world and you can't just lerp them together.

I bring up the programmers working on a project example just to illustrate how more isn't always better even if it theoretically can be.

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

#467

Post by snovv_crash » Tue, Nov 01, 2022, 6:23 AM UTC

touisteur wrote: post #458

snovv_crash wrote: post #454

Earlier quoted context omitted.

In theory a big phased array of cheap antennas is cheap, in practise not because you need to have equal impedance routing to all of the antennas, which means you need them all to be roughly equidistant to the amplifier. You could probably get away with blowing it up to the size of a large dinner plate, but then you also need a super stiff substrate to avoid flexing, and you need to convince manufacturers that they sh…

Thanks for the thoughtful reply. Modern phased arrays can have independent transmitters (synchronized digitally or with digital signal distribution) or you can have one 'cheap and stupid' transmitter and many receivers, doing rx beamforming, and as for complexity you mostly 'just' need to synchronize them (precisely). The receivers can then be made on the very cheap and you need some signal distribution for a central…

I know even for the small patch antennas we were looking at, the design of the waveguides was insanely complicated. I can't imagine blowing it up to something larger with many more elements.

If you wanted separated components to group together many antennas I suspect the difficulty would be accurate clock synchronization what with automotive standards for wiring. I'm still not sure I understand how they can get away without having rigid structures for the antennas, but this would be a critical requirement because automotive frames flex during normal operation.

Cars are also quite noisy RF environments due to spark plugs.

I guess what you're speaking of will be the next 10-20 years of progress for RADAR systems as the engineering problems get chipped away at one at a time.

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

#468

Post by touisteur » Tue, Nov 01, 2022, 7:55 AM UTC

snovv_crash wrote: post #467

touisteur wrote: post #458

Earlier quoted context omitted.

Thanks for the thoughtful reply. Modern phased arrays can have independent transmitters (synchronized digitally or with digital signal distribution) or you can have one 'cheap and stupid' transmitter and many receivers, doing rx beamforming, and as for complexity you mostly 'just' need to synchronize them (precisely). The receivers can then be made on the very cheap and you need some signal distribution for a central…

I know even for the small patch antennas we were looking at, the design of the waveguides was insanely complicated. I can't imagine blowing it up to something larger with many more elements. If you wanted separated components to group together many antennas I suspect the difficulty would be accurate clock synchronization what with automotive standards for wiring. I'm still not sure I understand how they can get away…

Ah I'm probably oversimplifying and working in an industry with a far higher price per sold unit, so have a very distorted view of 'easy' or 'recent'.

Thanks for humouring me. RADAR is a very fun and interesting topic.

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

#469

Post by lnsru » Tue, Nov 01, 2022, 8:11 AM UTC

oxplot wrote: post #457

lnsru wrote: post #424

Earlier quoted context omitted.

Let’s talk about my future Model X 2017 with free supercharging. The chassis is disaster from beginning to the end. The car has air suspension, it’s nice. But! You go with low setting, tires don’t last 10k miles. You go with high settings, axles are suddenly broken. After 60000 miles all parts under the car must be replaced. Not funny and not cheap either. Last car I heard of such nonsense was 25 years old Renault La…

> But! You go with low setting, tires don’t last 10k miles. It's well known that EVs in general due to their weight, and especially those with high torque cause the tyres to wear out much faster than their ICE counteparts. 10K miles sounds too low. Would love to know why low suspension setting on a Model X causes much faster wear, and whether for the same efficiency/range on a different vehicle, the tyres last signif…

This is typical thread talking about tyre wear: https://teslamotorsclub.com/tmc/threads/caution-model-x-hidd...

Nice tire on the outside, completely gone on the inside. There are now enough aftermarket parts and repair shops knowing what parts to replace and how to alight the wheels so that in low suspension setting the car is usable for long time. Sadly full air suspension potential can’t be used, but I can live with that. Internet is full of aftermarket parts claiming to solve these problems for all Tesla models. Finding proper repair shop is however hard. Love for details is not popular trait between underpaid mechanics.

I can tell you one thing: model X has no competition. Mercedes EQV comes closest, but is bigger and the range is very poor. VW buzz has no 7 seats and it’s price is insane. I also don’t like companies gazing apes: https://amp.theguardian.com/business/2018/jan/29/vw-condemne...

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

#470

Post by tsimionescu » Tue, Nov 01, 2022, 9:07 AM UTC

ion_fury wrote: post #438

tsimionescu wrote: post #286

Earlier quoted context omitted.

> also is there some intrinsic limitation of the dynamic range of cameras? people are talking about problems with dynamic range being intrinsic to cameras but im pretty sure that cameras and especially camera suites that do not have more problems with dynamic range than a human eye are possible to make and probably already on the market. I think it's possible that professional movie cameras (with the appropriate lens…

just take some cameras, set each one at a different exposure via something like smoked glass and composite the images in real time. i dont know, it just seems pretty easy.

Well, that increases the expenses from the sensors several fold (at least 2x of course, but I would guess closer to 3x-4x, depending on how many you need to cover the whole range).