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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]

#341
post #132

Earlier quoted context omitted.

> In other words, the results are better, but not enough to make up for the fact that Telsa can't support additional sensors without incurring a prohibitive amount of additional risk to Tesla. Risk to passengers doesn't appear to be a consideration. You may be right about the actual decision process Tesla went through, but Karpathy is right in principle. One of the first things he says is "there can be problems with…

Taking his point to the extreme why use 8 cameras? just use 4? 1? One photo-diode? Cameras can also fail at run-time there can (and is) be variability in how they're mounted, in the lenses, in the sensors. They can get blinded or not get enough light. Their cabling can fail random components can fail. Tesla has claimed that vision outperforms vision+radar but anecdotal reports don't seem to support that conclusion. I…

> why use 8 cameras?

At least 6 are needed to get a 360 degree view around the car, which obviously is necessary. Think of the 8 cameras as a single better sensor. It's a question of having one very good sensor then or many to fuse.

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

#342
post #316

This sucks for parking. It is simply (physically) not possible for the existing cameras to see the area directly in front of the car. So how would this work for parking? A: Add more cameras so there are no dead areas in front of the car B: build a model in vector space when driving towards a parking spot and assume blind spots don't change. (still sucks)

> It is simply (physically) not possible for the existing cameras to see the area directly in front of the car. Think about how a human driver does it, given his/her even worse vantage point. They model what's in front/behind the car from afar and remember what's where as they approach it. There are other signals as well, such as continuation of a kerb, etc. I think people keep forgetting that Teslas run hundreds of…

Human driver constantly turns head around to where he is Mos likely to hit something.

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

#343

Earlier quoted context omitted.

> ”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.

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.

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

#344
post #342
post #316

Earlier quoted context omitted.

> It is simply (physically) not possible for the existing cameras to see the area directly in front of the car. Think about how a human driver does it, given his/her even worse vantage point. They model what's in front/behind the car from afar and remember what's where as they approach it. There are other signals as well, such as continuation of a kerb, etc. I think people keep forgetting that Teslas run hundreds of…

Human driver constantly turns head around to where he is Mos likely to hit something.

Well, the car has 360 degree camera view, with far wider coverage than a turning head in a driver seat.

And more importantly, it sees in all directions at all times.

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

#345

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".

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.

Not more sensors, different sensors.

In your metaphor it's like asking if you should have project managers as well as engineers on your project. And Tesla has decided that having only engineers allows them to focusing on having the best engineers. And they avoid the distraction of having to manage different types of employees.

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

#346
post #3

Earlier quoted context omitted.

But the question at hand is system control, not locomotion! You're not asking the automation to walk (well, I mean someday we will, but Teslas have wheels), nor the aircraft to flap. We want the automation to do what a human pilot would do. And that works with eyes. No, I think this argument is largely correct. And frankly settled: anyone who's driven recent FSD beta versions knows very well that the cars "see just f…

> The LIDAR folks were wrong, basically I think your mistake is thinking LiDAR exists to solve the happy day scenario. It doesn't. Vision is sufficient for the majority of use cases. Where LiDAR comes into its own is in the edge cases because it almost guarantees accurate bounding box detection. Which is where vision is at its weakest. So I want to know what does FSD do when it sees a billboard of a person or when it…

As long as the billboard is not moving into the street or standing in the middle of it what would you expect it to do ?

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

#347

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".

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

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

#348

Earlier quoted context omitted.

Humans work with much more than just eyes. We subconsciously move our heads in case of uncertainty in the stereo vision algorithm and have pretty good IMUs. And yet, everyone has the experience of wrongly focusing on a repeating vertical pattern (vertical blinds or coiled cord for example) and getting disoriented. And every experienced driver has experienced at least some of the following: a moment of glare from a we…

A good human driver also gauges the limits of their own experience and 'phase transitions' into a more cautious mode of driving. Is that something the algos can do? Infer the familiarity of the situation?

The planning absolutely should take that into account and it does somewhat already. When it is really tight for example, it can slow down to a crawl.

It should do that in many cases, wet roads, busses with open doors, busses in general maybe, blind corners (does that already to some degree), many people nearby etc.

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

#349
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 ?

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

#350
post #111

Earlier quoted context omitted.

do you have data to back this claim?

Have you been keeping up with the Twitter deal? This was covered Friday. https://www.bloomberg.com/news/articles/2022-10-27/tesla-eng... And the corresponding HN thread: https://news.ycombinator.com/item?id=33365065

I have not been following the whole thing super closely, no. Thank you for the links.
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