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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]

#231

Post by freejazz »

xodjmk wrote: post #213
YZF wrote: post #113

Earlier quoted context omitted.

Tesla's cameras often get blocked by rain or blinded by the sun or not see that well in the dark. It's really hard to imagine those cameras replacing the ultrasonic sensors which do a pretty good job at telling you where you are when you're parking etc. I can't see how the camera is going to detect an object at pitch dark and estimate the distance to it better than an ultrasonic sensor. But hey, if people ding their…

You are greatly overestimating the functionality of the sensors, and underestimating the importance of the rest of the system. Sensors are important, but the majority of the work, effort and expense is involved with post-sensor processing. You can't just bolt a 'Lidar' on to the car and improve quality of results. Andrej and other engineers working on these problems are telling everyone the same story. The perfect so…

"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?

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

#232

Post by xodjmk »

mbreese wrote: post #171
galangalalgol wrote: post #151

Earlier quoted context omitted.

One interesting side effect of only using visual sensors is that the failure modes will be more likely to resemble human ones. So people will say "yeah, I would have crashed in that situation too!". With ultrasonic and radar and ladar it may make far fewer mistakes but it is possible they might not be the same ones people make, so people will say "how did it mess that up?"

Sadly, that’s the worst way to actually design the system. I’d rather have two different technologies working together, with different failure modes. Not using radar (especially in cars that are already equipped) might make economic sense to Tesla, but I’d feel safer if visual processing was used WITH radar as opposed to instead of radar. I also expect an automated system to be better than the poor human in the drive…

You have to eventually decide to trust one or the other, in real-time. So having multiple failure modes doesn't solve the problem entirely. This is called 'Fusion', meaning you have to fuse information coming from multiple sensors together. There are trade offs because while you gain different views of the environment from different sensors, the fusion becomes more complicated and has to be sorted out in software reliably in real-time.

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

#233

Post by YZF »

sumedh wrote: post #220
YZF wrote: post #113

Earlier quoted context omitted.

Tesla's cameras often get blocked by rain or blinded by the sun or not see that well in the dark. It's really hard to imagine those cameras replacing the ultrasonic sensors which do a pretty good job at telling you where you are when you're parking etc. I can't see how the camera is going to detect an object at pitch dark and estimate the distance to it better than an ultrasonic sensor. But hey, if people ding their…

> 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.

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

#235

Post by nelox »

“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 of a tornado siren, similarly. Loud throbbing motorcycles do much to improve rider safety simply due to them broadcasting their presence. At railway level crossings, drivers should slow down, look and listen for oncoming trains. The smell of wildfire or bushfire smoke provides enhanced warning or nearby danger. So to say vision is sufficient, does not fully take in to account the driver experience, especially where safety and situational awareness are concerned.

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

#236

Post by seanmcdirmid »

flashgordon wrote: post #51
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…

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.

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

#237

Post by xodjmk »

freejazz wrote: post #231
xodjmk wrote: post #213

Earlier quoted context omitted.

You are greatly overestimating the functionality of the sensors, and underestimating the importance of the rest of the system. Sensors are important, but the majority of the work, effort and expense is involved with post-sensor processing. You can't just bolt a 'Lidar' on to the car and improve quality of results. Andrej and other engineers working on these problems are telling everyone the same story. The perfect so…

"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 include data Fusion processing. Both methods have trade-offs.

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

#238

Post by dmix »

JumpCrisscross wrote: post #214
dmix wrote: post #150

Earlier quoted context omitted.

Isn’t that his point though? Where exactly is he not saying that? I listened to his answer three times and I’m not able to come up with a different interpretation than that.

> 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.

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

#239

Post by ion_fury »

JumpCrisscross wrote: post #218
ion_fury wrote: post #95

Earlier quoted context omitted.

lex's comment did not strike me as a dig. i am actually concerned by your comment because it makes me wonder if i am missing other things too? it just doesnt seem like a dig. it seems like he thought of something funny and wanted to share it. am i alone in this? and also i dont understand your assertion that it was some kind of cynical maneuver to re-frame the question. he could have also said "yes, more sensors are…

> did not strike me as a dig It wasn't a dig. It was calling out a bullshit move that, in my opinion, Andrej deployed out of panic more than strategically. (My evidence for this being Andrej eventually gave a good answer.)

i just dont get it. lex says "lets re-frame the question: can a language model drive a car?" this doesnt have any insinuations about andrej's intentions or motives. if it were calling out bullshit it would be "lets re-frame the question: why is elon musk never wrong?"

lex kisses elon musks ass, last time i checked hes on musks side in the lidar debate and also lex has a record of listening patiently no matter what and i have never known him to check people or "call out their bullshit." lastly, what andrej did wasnt a bullshit move. re-framing a question has never been known as something people do only when they are being deceptive and it is very common in intellectually honest answers/explanations in my experience.

im still shocked because usually i see what other people see. but people calling this a dig/bullshit came out of left field for me. i hope i dont miss stuff like that more than i realize...

edit: i read your comment again and i didnt read it right. he panics, gives himself some more room, lex acknowledges this but in a prickly way. it makes sense but im still upset because when i watch it all i see is lex making a joke. i guess i have severe autism.

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

#240

Post by n0tth3dro1ds »

pmarreck wrote: post #114
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…

Two thoughts: 1) He's not touching on the software cost of integrating different sensor data into the same trained machine learning model; it is likely far simpler to just stick to stereoscopic vision data (the same thing the human genome decided!) 2) That said, it seems at least theoretically advantageous to have a sensory system that exceeds that which humans are limited to; things like LIDAR can work in complete d…

>it is likely far simpler to just stick to stereoscopic vision data (the same thing the human genome decided!)

There’s a lot more to perception while driving than just stereoscopic vision.

First, your stereoscopic “cameras” (eyes) are mounted in free-rotating sockets, which are themselves mounted in a rotating and swiveling base (your head/neck). Your eyes can do rapid single-point autofocus better than any existing camera. They also have built in glare mitigations —- squinting, sunglasses, and sun visors. This system is way more advanced than fixed cameras. Yes, even an array of fixed cameras with a 360 degrees field of view.

Then you have your sense of touch, your hearing, and your equilibrio sense. You feel motion in the car. You feel vibrations in the pedals. You hear road noise, other cars, sirens, and the engine (not much in EVs). You smell weird smells and know when you’re driving with your e-brake on or when there’s a skunk nearby. There’s a lot getting fused with the vision to make it all happen, and I think you’d be surprised how “broken” your driving capabilities would be if you took one of these “background” senses out of the equation.

My anecdote: I drive a manual transmission car. A few months back, I woke up with no hearing in my right ear. Spooked, I drove to urgent care. I could not drive well at all —- I was holding low gears for way too long. I learned that I use hearing almost exclusively to know when to shift. If you had asked me beforehand, I probably would have said that I’m visually monitoring the tachometer to know when to shift. Not the case. Also, I had a TERRIBLE sense of my surroundings. As I drive, I’m definitely building a model of the environment around me based on road noise, sound from other cars, sirens, and the like. Without hearing in just one ear, I felt very disconnected and unsafe. Living in California where lanesplitting is legal, I had several motorcycles catch me completely off guard. I had my hearing restored at urgent care and everything went back to normal immediately on the drive home.

I think Andrej and Tesla massively overestimate vision’s sole ability to solve the problem. Humans are fusing lots of sensation to drive well.

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