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2 dead in Tesla accident "Noone wasdrivingthe car" 15

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MartinLe

Civil/Environmental
Oct 12, 2012
394

“no one was driving” the fully-electric 2019 Tesla when the accident happened. There was a person in the passenger seat of the front of the car and in the rear passenger seat of the car.

the vehicle was traveling at a high speed when it failed to negotiate a cul-de-sac turn, ran off the road and hit the tree.

The brother-in-law of one of the victims said relatives watched the car burn for four hours as authorities tried to tap out the flames.

Authorities said they used 32,000 gallons of water to extinguish the flames because the vehicle’s batteries kept reigniting. At one point, Herman said, deputies had to call Tesla to ask them how to put out the fire in the battery.
 
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The US is not Sweden, in a number of ways...

1) our drivers as a whole are generally less competent, due to less training required for licensing and less emphasis on the fact that driving is a necessary skill to cultivate (the second one is mostly my opinion but I'd argue for it's truth)

2) Even areas with heavy winter climates (for the US), winter tires are not universal. In the great north of the US (areas like Michigan, Minnesota, Montana, Wyoming, etc) certainly some people keep, maintain, and use a winter tire set, but it's far from universal. Most people don't understand the difference and don't bother.

3) Studded tires are illegal in a lot of jurisdictions if there isn't an ice cap on the road, and roads in major cities are scraped of ice and salted - meaning that studded tires are extremely rare. The people who do have a winter wheel set are typically running a winter specific, non-studded tire (ie blizzak)
 
So the conclusion is,
that you should not allow Americans to build self driving cars,
because they are under average drivers to start with and they do not know the concept of black ice, winter tires with or without studs. [ponder] hmm that can work for me.


“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
I cannot see LiDAR spotting this, although it might look like a big hole in the road

That's a distinct possibility; my personal experience from a company project many years ago is that LIDAR beams do tend to get sucked up by water, resulting in very little, if any, reflected energy, while land/pavement did a passable job of providing some reflectance. So, I would indeed expect ice to be a black hole in the pavement, but the so-called AI behind the typical LIDAR would need to be programmed for that specific occurrence and try to determine whether it's just puddle water vs. black ice, which would require some form of temperature measurement as RS suggested.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
IRstuff,

My background is LiDAR. IR reflects very well off of smooth water. Given that the smooth face is being scanned at an extremely oblique angle, I would expect that the return would be from whatever is beyond the smooth surface. If the robot compares that return to its internal maps, we may have a reliable algorithm for detecting black ice. Puddles need to be slowed for too. An alternate reason for no-return is that there is a hole in the road, requiring the robot to come to a full halt.

As I have noted in other posts, you all will not enjoy following a robot car on the road.

--
JHG
 
Yes, but since the reflection heads off into the sky, there's going to nearly zero return, plus, anything that did come back might well be outside of the range gates of the receiver, again, resulting in nothing, or possibly a boatload of noisy ranges, which the processor would likely blow off.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
This is I think one part of the puzzle. Why do Teslas on Autopilot slam into white trucks and other big stationary objects? here's the vision from a single camera, it's a scene from a 1960's classic film called Vanishing Point

vanishing-point1_jeeras.png


The dark gray square marked This one is in fact a stationary box truck, as anybody who likes doing 3rd angle projections can prove, yet it is invisible from one camera. Now, you might hope that more cameras would reveal its actual shape, but you run into resolution at distance problems and a relatively narrow baseline.


Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
The binocular effect with multiple cameras is typically only for determining range via parallax; at distance there isn't enough information from the sides of an object to determine whether it's actually 2D or 3D, and wouldn't work on a truck necessarily, even if it were close, because a trailer is too bit for the camera to see its ends. A LIDAR, on the other hand, can at least determine whether the object is simply painted on the ground or actually has height above the ground. Smart people still can make mistakes; Musk's aversion to LIDAR makes Tesla's obstacle avoidance weaker, by far.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
...a neat 'dark' movie. I recall it and have a copy of it somewhere from a VHS tape if memory serves.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
GregLocock,

I know that Tesla does not like LiDAR. Intel makes what it calls its RealSense D435 depth camera.. I have seen one work. It uses two IR cameras, and its software compares the two images to work out 3D. It has a third colour camera to provide colour, and an IR projector to illuminate the target when things are dark out. It has a range of about 10m.

10m range is totally inadequate for a motor vehicle travelling at highway speeds, but you can use bigger cameras, and mount them on either side of the vehicle. I am not sure that IR[ ]illumination at 100m is a good idea.

One of the biggest hazards of winter driving on busy roads is all the slush that gets thrown up onto windows and your various lights. This will wind up all over the robot's cameras and LiDAR, and there needs to be a better strategy than pulling over to the side of the road and waiting to be rescued. Perhaps we can design a squeegee that is ejected from the glove box, so that the passenger can clean everything.

--
JHG
 
If only there were something that could go back and forth and wipe off the cover for the cameras and LIDAR.

If it could be figured out, it might also adapt to windshields.


spsalso
 
" I am not sure that IR illumination at 100m is a good idea"
Deals with pesky pedestrians though. Bring your own barbecue sauce.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
spsalso,

Windshield wipers work well in most rain. They work less well on ice as it collects on the window as you are driving.

--
JHG
 
So I suppose it might work to heat the "windshield" so ice wouldn't form, and perhaps use windshield fluid for the salt.

Surely Elon could get behind that.



spsalso
 
Window heaters work pretty well if it's pure rainwater; slush, on the other hand, contains dirt/mud, etc., which will get baked onto the glass, so not sure if that's a "clean" solution. Windshield wiper fluid can be loaded with alcohol to drop its freezing point, 50/50 will get you down to -32C

ethanol_water_solution_freezing_flash_point.png


TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
Why not just rotating self-cleaning lenses similar to those used in action-sports cameras? They're capable of dealing with mud, sleet, snow, molten balls of rubber, etc.

Precision guess work based on information provided by those of questionable knowledge
 

It smears and abrades the windscreen.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
Demented said:
Why not just rotating self-cleaning lenses similar to those used in action-sports cameras? They're capable of dealing with mud, sleet, snow, molten balls of rubber, etc.
It's not a rotating, self-cleaning screen... it's a clear tape that sits across the lens, and tape length is (obviously) limited. The tape is replaced after every race. I wrote the firmware that (among other things) controls the tape-winding stepper motor (Broadcast Sports designs/manufactures the vast majority of camera systems used in sporting events, like Nascar, F-1, etc..

Dan - Owner
Footwell%20Animation%20Tiny.gif
 
MacGyverS2000,

There is such a thing as a clear[ ]view on a ship. The window is round and it rotates at several thousand RPM to remove water. They are not practical on cars since they do not provide the field of view a driver needs. Sticking one on each and every optical device on a car, including a 360[°] LiDAR, will be expensive and complicated.

I was not claiming that there is no way to clean a windshield. I am an experienced winter driver. When you drive in the winter, you spend significant time and effort cleaning windows.

--
JHG
 
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