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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]

#241

Post by throwaway09223 »

YZF wrote: post #233
sumedh wrote: post #220

Earlier quoted context omitted.

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

A car typically doesn't have lights shining in all directions. My Tesla doesn't at an rate. At night, backing into my driveway, I can barely see anything on the back-up camera unless the brake lights come on. If it's raining heavily it's much worse. But the ultrasonic sensors are really good at detecting obstacles pretty much all around.

Reverse lights are literally mandated by law. Your Tesla has them, and if they're not bright enough that's a fairly cheap and easy problem to fix relative to the alternatives.

Ultrasonics struggle in the rain, btw.

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

#242

Post by katbyte »

et2o wrote: post #193
syntaxing wrote: post #127

Earlier quoted context omitted.

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.

For the specific task of (for example) cooking a steak it’s not hard to envision a computer vision algorithm coupled with a model with a some basic knowledge of the system (ambient temperature, oven/stove temperature, time cooking, etc.) doing an excellent job.

You cannot use vision to see the state of the side of a steak touching the pan, nor the internal temperature.

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

#243

Post by martindbp »

amelius wrote: post #90
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…

The problem with self-driving is that it is based on data, but the environment may change. See e.g. the case where Tesla thinks that firetrucks are roads. So if fashion changes, pedestrians may suddenly look like road too, as just an example. Another problem is that state-of-the-art classification networks have an accuracy in the 90% range. Given that a car has to take hundreds of decisions in a single ride, then eve…

> state-of-the-art classification networks have an accuracy in the 90% range.

If you're referring to ImageNet SOTA, is has 20000 different classes, including 120 different dog breeds [1]. This is a vastly different task than reliably detecting pedestrians where Tesla can actively curate a dataset of hard examples (from their fleet), whereas ImageNet is fixed, sometimes with low quality labels and as few as a couple of hundred examples. Tesla can also pick a point on the ROC curve to give higher recall but more false positives (which is important for VRUs specifically). Another big factor is that Tesla is using video, not still images, which makes predictions even more robust.

And that's just for pedestrians, Tesla are also using a general ViDAR (visual LiDAR) which is trained to detect obstacles that do not have a specific class. The ViDAR again operates on image sequences, not a single image, and can thus pick out structure from motion.

[1] https://en.wikipedia.org/wiki/ImageNet

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

#244

Post by freejazz »

Nomentatus wrote: post #54
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…

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…

"But you still have to address his system argument"

Do you? It's his argument that he needs to substantiate... it's not my burden to confirm his conjecture. And even looking at it on its face... it's clearly self-serving bs. It doesn't seem to be a problem for any other car company, so I'm a bit confused as to why it's such a problem for Tesla. Of course, the obvious answer is that Tesla is cheap and doesn't want to pay to have a team that would have sufficient bandwidth to do what every other car company and self-driving system is doing...

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

#245

Post by oxplot »

rootusrootus wrote: post #223
oxplot wrote: post #221

Here's the summary (mixed with observations from Munro and past Tesla presentations): - Costs money: the physical sensors (a dozen of them), wiring it up, assembling it, maintain inventory, code it, etc. - Time spent on maintaining, improving software stack for the non-vision sensors as well as efforts needed to fuse the data with vision, takes away from focusing on vision alone. It also holds back vision in relevant…

That's great for them. But when I'm shopping for a car, I get to choose between a manufacturer that installs the extra sensors and seems to be able to get them to work, and Tesla. Used to be that Tesla was blazing a trail and if you wanted a good EV, that was what you got. Now, if you want the best EV, it's usually not going to be a Tesla. And I don't see that they're making any decisions that will regain them that t…

> Now, if you want the best EV, it's usually not going to be a Tesla.

Would love to hear what you consider "good" and what specific EV ticks the most good features that a Tesla Model 3 doesn't.

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

#246

Post by freejazz »

croes wrote: post #163
jandrese wrote: post #129

Earlier quoted context omitted.

> 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.

>We do not. But not because of a lack of visual information. Most of the time it's a la k of concentration or an overestimation of one's own driving abilities.

Here is some shocking news for you. It's not your eyes driving the car... its your brain.

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

#247

Post by JumpCrisscross »

dmix wrote: post #238
JumpCrisscross wrote: post #214

Earlier quoted context omitted.

> 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.

I don't agree Lex is a skilled interviewer, he's great at creating interesting conversations in the aw-shucks way Joe Rogan is, but he mostly plays a fanboy role. I still love a Lex interview. Otherwise I agree.

> don't agree Lex is a skill interviewer

Fair enough. Seemingly practiced may be a better description. (I'm not super familiar with his work.)

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

#248

Post by RC_ITR »

eightysixfour wrote: post #219
RC_ITR wrote: post #208

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. 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.

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 serious self-driving car/tractor-trailer out there uses radar as a component of its sensor stack because Lidar and simple imaging is not sufficient.

And that's the point I was trying to make - we agree it's trivial for radar to find things they just need sensor fusion to confirm the finding and begin motion planning. This is why a real driverless car is hard despite what Elon would like you to believe. There is no one sensor that will do it. Full stop.

And this cuts to the core of why Tesla is so dangerous. They are making a car with AEB and lane-keeping and moving the goal posts to make people (you included) think that's somehow a sane approach to driverless cars.

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

#249

Post by [deleted] »

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.

[deleted]

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

#250

Post by freejazz »

xodjmk wrote: post #237
freejazz wrote: post #231

Earlier quoted context omitted.

"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." It has everything to do with cost cutting?

Lidar vs. Stereo camera vs. multiple cameras vs. ultrasound is a separate problem that engineers are trying to solve, not how can we sell cheaper mops. The decision to not use Lidar, as he says, and is the common debate being explored by people working on autonomous driving is whether it makes more sense to focus on stereo image sensors with highly integrated machine learning, or maybe use Lidar or other sensors and…

"Lidar vs. Stereo camera vs. multiple cameras vs. ultrasound is a separate problem that engineers are trying to solve, not how can we sell cheaper fucking mops."

Okay? Tesla is a car company and they are absolutely trying to sell a cheaper car. That's obvious to anyone that's been in one.

"Both methods have trade-offs."

Right, isn't that why most other systems use both?

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