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 had live so they wouldn't be pointed at each other, but in practice it seemed to not be a huge issue.

BTW I once gave you guff about continuing to bring up Conti's flash LIDAR, and in retrospect I wish I hadn't, I really enjoy your contributions here.

The SNR for flash Lidar is really low because you spread the beam out over such a large area.

Most automotive Lidar already operate in a “photon starved regime”, ~200-300 photons per return[0]. If you spread that over the entire scene, your snr drops quickly.

This forces you into 1550nm, and a large detector array and high power laser at 1550nm is extremely expensive.

As for MEMS, it’s been a while but I think FOV/steering angle range , steering speed and even maximum beam power were concerns

EDIT: my Lidar friend Jake reminded me that the appetizer size is also an issue with MEMS- smaller aperture = less light collected = lower SNR

[0] https://www.hamamatsu.com/content/dam/hamamatsu-photonics/si...

Continental is folding their automotive LiDAR division and is laying off everybody.

> They work OK, but cost too much.

Costs have dropped dramatically in the past 20 years and continue to do so.

> There needs to be a cheap, flush-mounted replacement for those things.

Why? Corners are the optimal mounting position for maximum visibility. It allows the car to -in-effect- see around corners in ways no centrally mounted sensor can.

> Waymo needs to solve that problem before they do New York.

What? Because of vandalism?

Which Tor hidden service was this?

Asking for a friend...

Drivers can also be blinded by consumer grade laser pointers.

If someone starts attacking safety systems physically I would expect they will get quite a bit of jail time.

The issue isn't one of fixed vs rotation, it's that radar can't fundamentally achieve the resolution necessary to distinguish important features in the environment. It's easily fooled by oddly-shaped objects, especially concave features like corners, and so while it's great for answer the question of "am I close to something" it's not reliable for telling you what that something is, especially at longer ranges.

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.

Very high tech radars can generate amazing imagery, but they'll never top what lidar can do. Conceptually they're both doing the same sort of thing using EM radiation, but lidar uses a much smaller wavelength which gives it an intrinsic resolution advantage. Particularly at distances and with hardware sized relevant to cars.

In a recent No Priors podcast with the Waymo Co-CEO Dmitri Dolgov, he talks about how they evaluated just driving with cameras and how it isn't good enough for full autonomy and doesn't meet their bar for safety [1].

1: https://www.youtube.com/watch?v=d6RndtrwJKE&t=1119s

It‘s not just Musk. Most automobile manufacturers have maintained that they need to find a way to do it with cheap and pretty sensors.

So there's a video of him addressing this - he doesn't hate the tech. He mentions that it's wildly expensive for cars. But, they use it heavily for SpaceX

Because Musk thinks is much much smarter than he actually is and refuses to listen to anyone. And between how many people he fired at Twitter, Tesla, and soon the US Federal Government I think he gets off on it.

Musk has said several times Lidar is great. It's just a stupid idea for automotive use and he's not wrong.

There's nothing similar in nature for a reason.

No, there’s a class system for laser safety

The rating is for you to stick your eyes right up to it for a long period of time and still be fine

1550nm LiDAR Damaged Sony Camera at CES - http://image-sensors-world.blogspot.com/2019/01/1550nm-lidar...

I know we are talking about car type lidar, but the iPhone Pro has a type of one and gets a depth map of photos. So you’re shooting it everyone you are taking photos of.

They should not be. In theory they can be, but there are strict regulations to prevent that.

Waymo tried cameras-only recently as a research project.[1][2] They seem to do about as well as Tesla, which they don't consider good enough.

[1] https://www.forbes.com/sites/bradtempleton/2024/10/30/waymo-...

[2] https://arxiv.org/pdf/2410.23262

You can, they are just expensive (other than iphone). Maybe 8k for a handheld basic one (e.g. Trion P1), $15k for a drone attachment (e.g. DJI Zenmuse L1) - more for the ones surveyors use proper including the tripod-mount ones.

At the consumer end photogrammetry tends to just be so much cheaper that its preferred unless you really need defined accuracy at a high level of detail. Lidar tends to work currently much better in an industrial/professional context because its more accurate. Whether Lidar will make the jump to lower cost / consumer level is the big open question (and basically the same issue as for cars here)

I was wondering this too, although for a different use-case. A couple years ago I was walking through a field/vacant lot not far from Centralia, WA and I came across what I think is a grave.

The (supposed) "grave" was roughly human-sized and human-shaped, the ground was concave, sunken in and deepest at the center, and it was encircled with stones that were slightly larger than grapefruit.

The reason I suspect it's a grave is because I stumbled upon a very similar-looking thing at a historical site in Tooele county Utah named Mercur cemetery.

With Lidar I could prove/disprove my grave theory, correct?

I think this depends on your budget and what exactly you want to do. Do you want to scan your house from outside? Sounds expensive, would probably have to be drone-mounted, and the drone would fly around for a while (depending on the shape of the house.) Inside, and don't mind some minor inaccuracies? Not Lidar, but a Kinect from yesteryear may be enough.

Lookup the RPLidar family of devices. Cheap 1D, easy to work with. By 1D I mean that it measures ranges in 360degrees around the plane that it is spinning in.