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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]

#41

Post by alsodumb »

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.

Definitely agree with your second point! In theory, the reaction time and complete environment awareness should itself make an autonomous system way safer than human drivers.

In some way, I am against the philosophy of using HD maps + LIDAR data for highly accurate localization which most companies seem to be using these days. I believe that this approach is inherently brittle and is an 'easy way out' to the hard localization problem. I think more resources should be put into developing more natural, no HD map dependency techniques.

PS: It is my understanding that most of the major players were using HD maps, not sure if it is still true.

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

#42

Post by another_devy »

01100011 wrote: post #19

I still suspect it's because they need to preserve compute resources for vision processing. Sensor fusion is likely eating up too much of their current HW and limiting their progress in other areas. I suspect Tesla will have to admit they need to upgrade the current HW before they ever 'solve' FSD.

I think not using LiDAR would be a good bet. LiDAR in nutshell allows you to give an object in vision 3D space, relative speed which 2 human eyes can do very fast. Problems with solving this in vision based input is in dataset and interpretation. Computer vision and AI can’t effectively apply a human drivers judgment with better camera and processing power, at least not yet.

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

#43

Post by jeromenerf »

ajross wrote: post #3
TheLoafOfBread wrote: post #2

This whole question about the vision boils down to "humans don't need it so cars should not need it too" the problem with this statement is that humans does not have wheels to move around, they have legs, but wheels are ridiculously simple compared to 4 legs tapping 160km/h on a highway. Same for birds - they also does not need jet engines to fly around, but imagine Airbus A380 flapping its wings and what kind of com…

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…

> We want the automation to do what a human pilot would do. And that works with eyes.

Humans can’t really turn senses off, so they have coffee when driving. Touch and hearing are quite important to “read the road”. Equilibrium too.

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

#44

Post by threeseed »

alsodumb wrote: post #32
diskzero wrote: post #21

Earlier quoted context omitted.

I am a principal engineer for a major autonomous vehicle company. You can break this statement down into two components: Adding more sensors slows his team now more than it improves system performance I'll take his word on this. It is a lot of work to incorporate multiple sensors. All necessary information is already in the pixel-space. I hate to disagree with someone as distinguished as Karpathy, but this is simply…

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…

> 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

But that doesn't mean that it translates to a car.

We constantly move our 576MP resolution eyes in multiple orientations in order to visualise a scene and focus on the most important areas. Cars have fixed, low-quality cameras.

We then interpret this data using the most advanced pattern recognition system the world has ever seen that is trained for at least 20+ years to fully comprehend the behaviour of everything this planet has to offer. Cars don't have anything close to this.

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

#45

Post by threeseed »

alsodumb wrote: post #37
kfarr wrote: post #31

Earlier quoted context omitted.

Full on agreement. There are literally videos of Teslas smashing into stationary vehicles on the highway at night using only vision camera for FSD. No way any rational actor could claim the visible pixel space is sufficient in that scenario compared to LIDAR, Radar, etc

It's funny you use Radar as an example of 'good sensor' while it is well known that most or maybe almost all?) of the stationary vehicle accidents you're talking about happened because of Radars inability to detect a stationary obstacle. On the other hand, RGB data does have that information, we use it everyday to avoid obstacles, even under foggy and rainy conditions (I'm no LIDAR expert but I know it sucks in rainy…

> Therefore, for this simple ADAS algorithm using roof mounted LIDAR, heavy rain does not prove to be a particularly important factor in the system performance.

https://www.mdpi.com/2079-9292/8/1/89/htm

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

#46

Post by cma »

diskzero wrote: post #21
bekantan wrote: post #16

He explains it quite well: all necessary information is already in the pixel-space and adding more sensors slows team down more than it improves the system performance. My understanding is that major blockers are not in perception area anyways, would be great if someone with relevant experience could comment if this is indeed the case.

I am a principal engineer for a major autonomous vehicle company. You can break this statement down into two components: Adding more sensors slows his team now more than it improves system performance I'll take his word on this. It is a lot of work to incorporate multiple sensors. All necessary information is already in the pixel-space. I hate to disagree with someone as distinguished as Karpathy, but this is simply…

Compare their occupancy map with what you get out of the latest LIDAR Waymo is using and it is scary (occupancy is harder as it fills in what is occluded, but Tesla's looks like Minecraft-style 1x1x1m resolution).

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

#47

Post by quonn »

throwntoday wrote: post #8
eachro wrote: post #4

So the key question is how much of an improvement does radar/sensors/etc give you over just using computer vision?

If we're to trust what Elon and the team said during the last few AI day, none. They stated that the ultrasonic and radar sensors were actually performing worse than their pure vision stack.

I‘m ready to be convinced that this will be true at some point for the ultrasonic sensors. But by design the radar can see things that vision can never see. It seems like a bad idea to take that away.

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

#48

Post by 0xfffafaCrash »

Seems like a very political answer from Andrej. Of course he’s not going to outright say “yeah, we’re prioritizing the profit margin over accuracy and safety considerations” if he wants to keep his job, but that seems to be the short of it. Others may choose to follow, at least in the short term, but it won’t be because of “entropy” making the system worse (you can always build a model without a data source and then refine the results based on the added value of a data source) but doing so just because it will save lives doesn’t cut it when the goal is to cut corners and costs to maximize profit. I can believe that some types of sensors aren’t worth the trouble in terms of additional signal to noise ratio, but I can’t believe this is one of them.

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

#49

Post by Nomentatus »

CharlesW wrote: post #11

I thought it was telling that Andrej immediately "reframed" the question because Lex asked the "wrong question". This is a classic evasion technique one learns from experience and/or media training. Lex's comment immediately after was a clever and gentle dig at Andrej's response. It seemed like all the "full cost" negatives Andrej mentioned were related to Tesla's ability to execute, and not what would actually produ…

Andrej did get around to answering the original question, he just wanted to say more, to put it into a bigger frame with more context. I had the same "weasling" concern at first; but his answer was more or less "You lose more than you gain, but yes there was a small delta; in exchange for which any organization would take on not just an economic hit but a lot of additional opportunities for process and maintenance errors; plus distracting the team." So he'll agree that in an ideal world you'd want 'em, just not want 'em that much; but in the real world, more geegaws that aren't really pulling their weight are a terrible idea.

Although he didn't explicitly say so, neither his answer nor Elon's "take it out 'cause you can always put it back in if it turns out you really need it" philosophy absolutely rule out lidar coming back in the future if some remaining edge case just requires it. Clearly he thinks this is quite unlikely, however.

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