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A Short Introduction to Automotive Lidar Technology

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Re: A Short Introduction to Automotive Lidar Technology

#162
post #24

Earlier quoted context omitted.

Theoretically if a human can drive a car using a pair of eyes connected to brain, it should be possible to do that using two cameras connected to some kind of image processing unit.

In theory. In practice neither the cameras nor processors available in cars function anywhere near human level.

It's not even entirely true in theory. We use a lot of our senses when driving. Force feedback on the wheel. Sounds from the environment. Inertial senses. And our vision isn't fixed, its constantly moving.

And yeah, as you mention, cameras don't really have the same level of range our eyes have and computers don't operate in the same way.

Re: A Short Introduction to Automotive Lidar Technology

#163

Earlier quoted context omitted.

Airplanes don't flap their wings and boats don't wag their tails. Assuming that all technology should imitate nature is a naive engineering principle. The solution should solve the problem within the given constraints.

Nature came up with something much better in both those cases. Portable, energy efficient, light, doesn't need refined oil, tightly steers... Boats and aeroplanes are terrible in comparison. They only work due to a huge network of global effort.

I don't see many birds around able to carry an extra 280,000lbs for 2,300 miles without having a meal.

Re: A Short Introduction to Automotive Lidar Technology

#164

Earlier quoted context omitted.

Good question! You're right, this is surprisingly hard to Google. It looks like the FDA is responsible. I would not have guessed that! The National Highway Traffic Safety Administration (NHTSA) would have been my guess, but I'm not finding much there. They have a spec for LIDAR speed measurement devices, and one for the required sensors in vehicles, but nothing on the the output of said sensors. > For manufacturers o…

Sorry, I don’t believe the FDA is doing anything more than stamping a Class 1 or class 2 sticker on component parts. They are not testing LIDAR arrays in situ under simulated driving conditions I would like to see crash test dummy style research around vehicular LIDAR

Classification should be sufficient. Remember that LIDAR is invisible, so distraction or flash-blindness are not relevant, just health effects. Class 1 has already been thoroughly tested and deemed "safe even for long term intentional viewing." Class 2 is visible only, so any LIDAR systems above 5mW would be Class 3, which are deemed harmful to humans. You can put a Class 3 laser in public (see laser light shows) but the FDA regulations require an indicator and to give the public enough warning to get clear if desired. These restrictions are going to make anything but Class 1 LIDAR exceedingly difficult for use in automotive applications.

Re: A Short Introduction to Automotive Lidar Technology

#165
post #22
post #9

Earlier quoted context omitted.

I believe automotive radar has a cone of sensitivity that is read as a single "pixel" worth of data. Even if the radar spun like lidar, the radar cone of sensitivity is thousands of times wider than the lidar beam so you can't make much of a picture with radar.

IIRC the data coming out of the Conti radars was preprocessed to give bearing, distance, and size of an object in the FOV of the unit. I don't know if I ever saw the true raw data out of one of them, but I'm curious what it looks like.

"Size" might be as simple as radar cross section. Not necessarily a good thing for us squishy blobs.

Re: A Short Introduction to Automotive Lidar Technology

#166
post #21
post #8

That's a reasonable basic overview. I'm surprised that rotating scanners are still used. It's been twenty years since Velodyne built their first one. They work OK, but cost too much. I was expecting flash LIDAR or MEMS mirrors to take over. Continental, the auto parts company, bought the leading flash LIDAR company over a decade ago, but the volume market a big parts company needs never appeared. Waymo is still using…

Waymo have in house radar, I think in the 70GHz gap in the absorption spectrum. They're pretty obvious as sort of paperback book sized planes, mounted near other sensors IIRC. The old Velodyne units were actually susceptible to damage if you left two units running right next to each other. I did hear a proposal at some point for a different but similar unit to use GPS time to sync the rotations of all the units we ha…

I went down to Advanced Scientific Concepts in Santa Monica, CA, in 2003 to see their prototype flash LIDAR. It was on an optical bench aimed out an overhead door into daylight, nowhere near a product. It did work, but required strange InGaAs semiconductor processes and a timer chip stacked back to back against the sensor chip. Way too expensive to fab.

I thought that was going to be the future, and that technology would get cheap. But it's still expensive to fab such devices.

Re: A Short Introduction to Automotive Lidar Technology

#167

Earlier quoted context omitted.

That's a bold claim. Care to justify it?

Yeah, it only works in extremely controlled environments driving really slowly. The design is also flawed as it has to work with cameras anyway. The last thing you want is two systems arguing over what they see.

Nice, you just outed yourself as being completely clueless. There exist many good sensor fusion techniques for summing the output of disagreeing sensors.

Re: A Short Introduction to Automotive Lidar Technology

#168
post #21

Earlier quoted context omitted.

Waymo have in house radar, I think in the 70GHz gap in the absorption spectrum. They're pretty obvious as sort of paperback book sized planes, mounted near other sensors IIRC. The old Velodyne units were actually susceptible to damage if you left two units running right next to each other. I did hear a proposal at some point for a different but similar unit to use GPS time to sync the rotations of all the units we ha…

I went down to Advanced Scientific Concepts in Santa Monica, CA, in 2003 to see their prototype flash LIDAR. It was on an optical bench aimed out an overhead door into daylight, nowhere near a product. It did work, but required strange InGaAs semiconductor processes and a timer chip stacked back to back against the sensor chip. Way too expensive to fab. I thought that was going to be the future, and that technology w…

Si interpoisers are a pretty mainstream packaging technology nowadays, so that might help with the stacking bits.

Re: A Short Introduction to Automotive Lidar Technology

#169
post #120

Earlier quoted context omitted.

Karpathy said in some podcast that Tela uses LIDAR in training, and by doing this they can get a lot of the benefits. Not sure that all off the "worlds experts" agree with you that you HAVE to use LIDAR. Rate of progress for FSD has been very impressive lately. I personally think that its very plausible that Tesla might beat Waymo to large scale location independent autonomous driving.

The stats on the latest FSD are still terrible. It still needs human intervention far too frequently and is no where near being able to run without a human in the car or Tesla accepting liability for crashes.

> Rate of progress

Re: A Short Introduction to Automotive Lidar Technology

#170

Earlier quoted context omitted.

Based on presentations we've seen what sets Tesla apart are its datasets not the core technology. And those don't translate across to the Optimus bot.

I think they will though, I think the enormous corpus of video data and the supercluster that powers self driving development are the machine vision analog of internet scale text data that gave rise to LLMs. We'll see the same moment for vision models that text prediction models had once the data is there, where an enormous foundation model becomes much much better, especially at zero-shot tasks.

FSD is already using the fruits of this today with their end to end NN.

And based on what we've seen the results haven't improved enough to put them close to Waymo.

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