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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]

#441

Post by aeternum »

Maxion wrote: post #308
aeternum wrote: post #181

Earlier quoted context omitted.

Yeah that's fair. A CCD sensor basically converts individual photons to electrical charges. What Tesla has said they've done is thrown away all the traditional image signal processing & post-processing which often includes a lot of exposure-related averaging. You're right though that we don't typically use real-time neural networks that operate based upon spike rate, so an interval needs to be chosen for photon count…

Lol this doesn't make any sense. The dynamic range of a fully sunlit California highway during noon in the summer (I.e. the brightness reading of the darket vs the brightest spot) is wayyyy higher than any existing sensor. You cannot ignore exposure, you have to choose which part of the scene you want within the brightness range that your camera sensor can capture. You will have areas of the scene that clip, in other…

Just keep the duration low so that you never saturate the sensor even in bright sunlight and let the NN do the summations.

At a fundamental level it is somewhat akin to bracketing except all that HDR processing/frame matching is performed within the NN rather than a traditional image processing stack.

The NN is better at this anyway since it must already be performing camera/pose motion tracking to correlate what it's seeing from frame to frame.

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

#442

Post by enragedcacti »

robocat wrote: post #436
enragedcacti wrote: post #425

Earlier quoted context omitted.

It could be reframed as saying we have a peak acuity equivalent to a 576MP camera of the same FOV with a theoretical max of 20 samples per second (50 ms to move targets, realistically probably more like single digits). The 8MP comparison is only relevant if there are so many targets that need constant full resolution that you can't focus on all of them or the targets are so large that they are larger than the peak ac…

That doesn't make sense: a camera doesn't get more pixels just because the camera is taking a video tracking something. Neither if it had zoom and a controlled gimbal.

If you turn that tracked video into a panorama it would. Or if you took 10 zoomed photos and stitched them over top of an unzoomed photo. The point is that unless the task demands more focus areas than the eye can focus on in a given window then the visual acuity (for the parts of the scene that matter) is higher than an 8MP shot of the entire scene.

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

#443

Post by bumby »

diskzero wrote: post #38
alsodumb wrote: post #32

Earlier quoted context omitted.

I think one should distinguish between 'all necessary information is already in the pixel-space' vs 'we already know how to extract all the information needed from pixel-space' The fact that (most) humans manage to drive around safely and successfully in current roads proves that the information needed exists in the pixel-space (not just current image, but say current + history). We don't yet have stacks that can suc…

I'll agree with you that there are still techniques to be discovered. I also agree that most humans manage to drive in challenging conditions, but their margins for error become slimmer and slimmer. I personally want my autonomous robot vehicle to be way more efficient and safer than the best human operator and also able to deal with conditions that any sane human would pull to the side of the road when encountering.

>their margins for error become slimmer and slimmer.

Can you elaborate on this? I've always felt like the margins of error are getting wider because the automotive tech (particularly safety features) are so vastly improved. I doubt people would be able to text and drive as much, for example, if they were driving a 1950s era Willys jeep just because it requires so much more attention to keep on the road by comparison to modern vehicles.

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

#444

Post by cbsmith »

robertlagrant wrote: post #359
cbsmith wrote: post #294

Earlier quoted context omitted.

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.

Approaching inclines aren't exactly hard to interpret from lidar either.

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

#445

Post by mrguyorama »

michaelt wrote: post #321
touisteur wrote: post #310

Earlier quoted context omitted.

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…

I've heard people on the internet claim that, in automotive radar the first thing they do when processing the signal is discard any stationary objects. Apparently this is because the vast majority of the time it's a sign or overhead gantry or guard rail - any of which could plausibly be very close to the lane of travel thousands of times per journey - and radar doesn't provide enough angular resolution to tell the di…

Indeed, my VW which uses a forward looking radar has signaled several times for stationary objects. In fact, the one time it literally stopped an accident was for a highway that suddenly turned into a parking lot. People keep repeating BS said by tesla and tesla apologists for why their cars run into stopped things and others seem to have less of a problem with it.

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

#446

Post by mrguyorama »

Reason077 wrote: post #257
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…

> ”There is no one sensor that will do it. Full stop.” Yet somehow, humans can drive cars with just a pair of optical sensors (mounted on a swivelling gimbal, of sorts). In theory, a sufficiently capable AI should be able to drive a car at least as well as a human can using the same input: vision.

Our two eyeballs plus brain is SO MUCH MORE than just two mediocre CCDs.

Our eyes provide distance sensing through focusing, the difference in angle of your two eyes looking at a distant object, and other inputs, as well as having incredible range of sensitivity, including a special high contrast mode just for night driving. This incredibly, literally unmatched camera subsystem is then fed into the single best future prediction machine that has ever existed. This machine has a powerful understanding of what things are (classification) and how the world works (simulation) and even physics. This system works to predict and respond to future, currently unseen dangers, and also pick out fast moving objects.

Two off the shelf digital image sensors WILL NEVER REPLACE ALL OF THAT. There's literally not enough input. Binocular "vision" with shitty digital image sensors is not enough.

Humans are stupidly good at driving. Pretty much the only serious accidents nowadays are ones where people turn off some of their sensors (look away from the road at something else, or drugs and alcohol) or turn off their brain (distractions, drugs and alcohol, and sleeping at the wheel).

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

#447

Post by mrguyorama »

gizmo wrote: post #375
2muchcoffeeman wrote: post #364

Earlier quoted context omitted.

> Yet somehow, humans can drive cars with just a pair of optical sensors (mounted on a swivelling gimbal, of sorts). This is wrong and I was surprised to hear them say it was enough in the video. We don't have car horns and sirens for your eyes. You will often hear something long before you see it. This is important for emergency vehicles. Once you hear it, a good driver will immediately slow down and pull to the sid…

Deaf people (or those who blast music) can drive. People who are blind in one eye can drive.

That might have something to do with the general intelligence prediction supercomputer sitting between the ears. If Tesla is saying they won't have real (not just an 80 percent solution that they then lie and say is complete) self driving until they develop an AGI, I agree

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

#448

Post by mrguyorama »

lolc wrote: post #343
bonestamp2 wrote: post #288

Earlier quoted context omitted.

Yes, a "pair" of optical sensors. Tesla is at a disadvantage compared to humans -- they do not do stereoscopic imaging, which makes distance of objects less reliable -- they try to infer distance from a single flat image. Humans having two sensors pointed in the same direction gives us a very reliable way of determining distance (up to a relevant distance for driving at least).

Interestingly, even people with missing stereoscopic vision are allowed to drive. We don't require depth perception to drive. The assumption is that they can compensate.

Binocular vision isn't even the only source of depth information available to humans. That's why someone missing an eye can still make reasonable depth estimations.

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

#449

Post by Nomentatus »

freejazz wrote: post #433
Nomentatus wrote: post #427

Earlier quoted context omitted.

Oy.

Pot, kettle, black.

Circling, circling, circling - but no specific analysis, citations, or criticisms of Tesla's stated logic. Gainsaying isn't a positive contribution to a conversation.

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

#450

Post by Nomentatus »

freejazz wrote: post #432
Nomentatus wrote: post #428

Earlier quoted context omitted.

Nope. There's definitely mapping, and then, much, much more. You're stuffing words in my mouth.

Not sure if I'm stuffing so much as removing the bluster

Ad hominem, but no content.
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