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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]

#351

Post by pcl »

kalleboo wrote: post #252
RC_ITR wrote: post #248

Earlier quoted context omitted.

So, yes, cars that are programmed to have AEB: perform well at AEB and not other tasks. We are in agreement here. (I even agree with you that those cars use Radar for AEB). Now, where we disagree is you implying that cars with AEB-level radar (literally $10 off-the-shelf parts with whatever sensor fusion some MobilEye intern dreams ups) are somehow the same as self-driving cars (the goal of Tesla Autopilot). Every se…

But if the radar just sees a static object and can't tell if it's an overhead sign or a car, and the camera vision is too washed out, how would sensor fusion help in your example?

A human driver slows down and moved their head around to get a better view when the glare from the sun is too strong to see well. I’d expect a self driving car to similarly compromise on speed for the sake of safety, when presented with uncertainty.

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

#352

Post by Nomentatus »

freejazz wrote: post #264
Nomentatus wrote: post #185

Earlier quoted context omitted.

Good point. I'm pretty sure it was poorer, Waymo really goes all-in on Lidar, they still top-mount it don't they? Waymo is also solving a much more constrained problem, with far fewer vehicles, so fewer accidents doesn't surprise me.

They are doing exactly what Tesla isn't willing to do and are being responsible in exactly the way Tesla isn't.

But it's an expensive dead-end for most purposes, esp re the insane mapping. Ok for city robo-taxis. Doesn't solve the real problem to be solved.

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

#353

Post by ClumsyPilot »

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.

> vision which is by far the highest accuracy and babdwidth

They are literally the least accurate of all sensors.

Radar tells you distance and velocity of each object. Lidar tells you size and distance of each object. Ultrasonic tells you distance. Cameras? They tell you nothing!

Everything has to be inferred. Have you tried image recognition algorythms? I can recognise a dog from 6 pixels, the image recognition needs hundreds, and has colossal failures.

We have no grip on the results AI will produce and no grasp on it's spectacular failures.

Driving will have to be solved without AI

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

#354

Post by Nomentatus »

freejazz wrote: post #261
Nomentatus wrote: post #256

Earlier quoted context omitted.

You still have to address the argument he makes that the net effect on risk of keeping the lidar was in fact negative. You're just gainsaying it. That's not a contribution to any discussion.

I have no doubt that might be the case; as I already explained, it's obviously due to the fact that they are cheap.

So you're again gainsaying his explanation, but gainsaying says nothing that helps anyone else make a decision. How are the rest of us who aren't psychic to know he's lying?

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

#355

Post by Nomentatus »

freejazz wrote: post #263
mensetmanusman wrote: post #119

Earlier quoted context omitted.

LiDAR has its own false positives that haven’t been solved, so it’s possible they believe that. I certainly was skeptical until alphago and alphafold happened.

That's especially amusing considering how if you view Go as a visual problem, it's beyond trivial compared to what is required to safely operate a motor vehicle (even just visually).

Yikes. I'd be a lot better Go player if it was just a matter of seeing the board.

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

#356

Post by ClumsyPilot »

eigenrick wrote: post #192
jeffbee wrote: post #97

Earlier quoted context omitted.

Tesla engineers are currently doing post-commit review of Twitter source code. Focus is the last thing I would credit them with.

I don't think it was your intent, but your statement makes it seems like all Tesla engineers are looking at Twitter code. I bet this number is closer to 4. Tesla has ca. 1000 software engineers working in various capacities. The ca. 300 that work on car firmware and autonomous driving are probably not participating in the Twitter drama.

4 people is enough to review source that was written by thousands of engineers at twitter? thats not even enough for architecture review

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

#357

Post by RF_Savage »

touisteur wrote: post #310
Reason077 wrote: post #253

Earlier quoted context omitted.

> ”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.” That crash occurred on a car which was using radar. Automotive radar generally doesn’t help to detect stationary objects. Further, that crash occurred on a vehicle with the original autopilot version (AP1), which was based on Mobileye…

I find very strange the claim that a moving doppler (pulsed doppler?) radar 'generally doesn't help to detect stationary objects'. I mean if the car is moving, it generates a doppler shift on all objects moving at a different speed, right? Maybe it's difficult for reasons of false alarm detection (too many stationary objects that are not of interest) but you can get very good results with tracking (curious about thes…

Especially when most car radars are FMCW radars. They not only do know the speed, they also know the distance.

Some of the newest car radars can do some beam formimg, but not all.

Most models have multiple radars pointing in multiple directions as that's cheaper than AESA.

Only just recently have "affordable" beamformer's come to the market. And those target 5G basestations.

So the spec in most K/Ka-band models starts at 24.250GHz, where the 5G band starts. While the licence free 24GHz band that the radars use is 24.000-24.250GHz.

If this was not bad enough there has been consistent push from regulators to get the car radars on the less congested 77GHz band. And there's even less afforable beamformers for that band.

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

#358

Post by throwaway4good »

Let me reframe the answer:

"We removed them because they cost money. And we are trying to make money ... at least right now.

Listen, this pure autonomous self-driving car stuff is never going to work, so who cares if we have these gadgets or not ..."

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

#359

Post by robertlagrant »

cbsmith wrote: post #294
kalleboo wrote: post #252

Earlier quoted context omitted.

But if the radar just sees a static object and can't tell if it's an overhead sign or a car, and the camera vision is too washed out, how would sensor fusion help in your example?

Lidar would make it pretty obvious whether it's a sign or a car, even if the camera didn't tell you. The part where the lidar doesn't bounce back at vehicle level would be a dead give away.

A approaching incline has entered the chat.

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

#360

Post by stonogo »

nelox wrote: post #235

“The world is designed for human visual consumption” and “[vision] has all the information you need for driving”. While vision may be sufficient, I would say that other senses, such as hearing, touch and smell augment driving very well. Especially with regard to situational awareness. e.g. The sirens of emergency vehicles are typically the first indication of their presence, which often can be felt as well. The wail…

One thing that Tesla engineers seem to keep forgetting is that human eyes are not fixed into a steel block. We can tilt our heads, crane our necks, hold hands up to block glare, and so much more. Human vision is responsive, adaptable, and not comparable to some cameras bolted to a car.

And even with all these advantages, tens of thousands of people are killed in car crashes every year. Some people make a compelling argument that this is evidence that human vision doesn't have all the information you need for driving. While I don't go that far, I do think autonomous driving has a long way to go.

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