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Comment by frik | Hacker News Reader

It's staggering that Tesla don't use LIDAR at all.

Sure LIDAR is more expensive but the data quality is very stable and good. Cameras won't work that well or at all in night or when the sun rays blend in morning / evening or in bad weather conditions like heavy rain or snow. All other self-driving cars I know of have at least a small LIDAR beside several other types of sensors.

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Lidar doesn't make sense for Tesla with the failure rate alone. They're mechanical devices, and they often have defects when produced at scale. They need to be replaced very often. This makes sense when you're doing vehicles as a service, but not as much for Tesla's use case.

What about the solid state LIDAR mentioned by the GP?

Needs to be mounted high up and then the car doesn't look cool anymore.

Once the cost goes down, multiple LIDAR units can be mounted behind the windshield. Cars designed for automatic driving should reserve the top inch or so of the windshield for sensors, with the optical sensor suite mounted at the front edge of the roof and covered with padding matched to the headliner. (Yes, auto glass today is often infrared-opaque to reduce heat input, but the IR-opaque layer could be omitted for the top inch.) Putting cameras behind the rear view mirror is already done, but more space may be needed.

The rotating Velodyne thing Google uses is an interim research tool. In production, expect to see better design.

With enough LIDAR units, full-circle coverage can be achieved. This is already being done with cameras. The rear and side units need less power and range than the front-facing units, so they can have a smaller collecting aperture, making them easier to place. For the front-facing units, the emitter can be spread out, allowing higher power. The rules on eye safety are concerned with the maximum power coming through a 1/4" hole (human eye pupil). If the laser emitters are spread out over the width of the windshield, the maximum power per unit area is reduced.

The CMU/Cadillac demo a few years ago managed to conceal all the sensors. It can be done. It just costs too much until one of the three companies claiming to be building low-cost automotive LIDARs Real Soon Now manages to deliver.

> Once the cost goes down...

> ...expect to see better design.

> ...costs too much until one of the three companies claiming to be building low-cost automotive LIDARs Real Soon Now manages to deliver.

All I see is future promises. Tesla wants to do this now, that too at mass market costs, independent of whether those promises materialize or not.

It also depends on how much you trust their R&D team. If they thought this was a week sensor suite and something else was just around the corner, they won't risk fitting their cars with inferior technology which would be obsolete in a couple of years, making all the collected data worthless. Yes I am aware they did this to existing cars lacking the full autonomy hardware, but I find that OK, since, for them, they never promised full autonomy to begin with.

> It also depends on how much you trust their R&D team

R&D doesn't make top-level budget decisions.

If the product fails, that's on Musk and Musk alone.

He takes credit for its successes. He can take responsibility for its failures too, as we would expect from any respectable CEO.

No, Tesla doesn't want to do automatic driving now. They want to hype it now. The software isn't ready yet. In their announcement, they say that the new hardware will, right now, support fewer automatic driving features than the current hardware.

Low-cost LIDAR is a problem that can be solved with money and a customer ready to buy a lot of units. So far, no car company has said "we'll take a million units a year at $100 if they meet these specs." It's lack of demand, not lack of technology. It's a risk for the LIDAR maker. There are automotive radars available better than those currently on cars, but they don't have a volume buyer yet.

You provided no evidence for the hype claim but even then you are contradicting yourself:

Statement A: Tesla is just hyping autonomous driving since no technology can deliver fully autonomous driving right now.

Statement ~A: Low-cost LIDAR is available to any high-volume customer, of which Tesla is one, given Model 3 demand. And LIDAR can deliver fully autonomous driving.

The point simply being, I have a hard time believing that even with good-looking, cheap LIDAR being a possibility, as you claim, Tesla chose to go with an inferior sensor suite, for no apparent reason.

What they're doing now is a minor retrofit to their existing crashes-into-big-solid-objects "autopilot". The Model 3 is at least two years away. By then, the technology should be better.

Volvo already has a concealed LIDAR in their self driving car.[1] Volvo will put 100 self-driving cars in the hands of ordinary drivers in Sweden in 2017. This is self-driving by the pros. Makes Tesla look amateurish.[2]

And Volvo is way ahead on marketing self-driving.[3]

[1] https://www.youtube.com/watch?v=2q00jIBhkq4 [2] http://www.volvocars.com/intl/about/our-innovation-brands/in... [3] https://www.youtube.com/watch?v=uDB6fFflTVA

As far as I understood the Volvo LIDAR is windshield mounted?

http://www.sae.org/dlymagazineimages/web/516/11702_15456.jpg

Making the necessary gubbins look cool is a job for the company's designers.

Spinny LIDAR on top is never gonna look cool unless your aesthetic is "Ghostbusters", but it's also already looking technologically obsolete.

   >> then the car doesn't look cool anymore.

This doesn't look cool either:

    >> There are videos of three separate Tesla crashes where the Tesla plowed into a vehicle partially blocking a lane.

Besides being almost as expensive as the car they mount on top and stick out like a sore thumb. This is the reason. It doesn't look cool. Amazed that people don't realize that.

In that sense, aerodynamics might play a role as well.

there are systems with LIDARs mounted next to the headlights.

LIDAR's high cost[1] is prohibiting it from being commercialized. This article below was dated 2015 so price might have actually gone down a bit - but still a few orders of magnitude higher than cheap ultrasonic sensors and cameras.

This is actually common problem not only for Tesla. We won't see LIDAR in production cars (you will certainly see them in prototype cars as usual) until its cost drastically reduced

[1] http://articles.sae.org/13899/

It's more than just high cost, LIDAR has issues with rain making it questionable in real world conditions. AKA, if you need some fallback, just use that fallback.

With range gating, you can do a lot with LIDAR in rain and fog.[1][2] It's possible to ignore all reflections out to a given distance, and you can adjust that distance. There's been a lot of work on this for the military. Automotive LIDAR units don't have this yet, but it could easily be added. If you have both range gating and "first and last", where you get the time of the first and last reflection, you can easily distinguish fog and rain from hard objects. The distribution of first and last times on fog and rain should look like Gaussian noise, while a hard target has near-equal first and last.

This is something we'll probably see in second-generation self-driving cars. With range-gated LIDAR and millimeter radar, self-driving cars will do far better in fog and heavy rain than humans do.

[1] http://www.sensorsinc.com/applications/military/laser-range-... [2] http://www.obzerv.com/en/range-gating-technology/core-expert...

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