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Tesla crash in September showed similarities to fatal Mountain View accident

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Re: Tesla crash in September showed similarities to fatal Mountain View accident

#551

Post by mirimir »

mdorazio wrote: post #535
Dylan16807 wrote: post #85

Earlier quoted context omitted.

> But once you do that, it gets tricky to determine when you should ignore the "stationary object" and when you shouldn't. That's not tricky. You never ignore it. A stationary object means that you will have to either stop or turn. You don't know which one yet, but you definitely know you'll have to take an action. If you haven't decided by some close point, you just pick one.

"Ignore" was probably the wrong word, but it is tricky. Remember that a vehicle is evaluating the environmental state at a given point in time to make decisions. Let's take the example of everyday driving on the freeway where you are following a car going the same speed as you. From your car's radar and camera perspective, the vehicle in front of you is stationary. It's not until you combine that information with add…

There's some confusion about what "stationary" means. I was using the external reference frame. So I called road signs etc stationary. But in the vehicle's reference frame, road signs etc have closing velocity.

Vehicles in front moving at the same speed aren't stationary in the external reference frame. They're stationary in the vehicle's reference frame. If one stops, though, it becomes stationary in the external reference frame, and has closing velocity in the vehicle's reference frame.

Sorry to be pedantic.

Re: Tesla crash in September showed similarities to fatal Mountain View accident

#552

Post by mirimir »

Piskvorrr wrote: post #300
mirimir wrote: post #104

Earlier quoted context omitted.

As I understand it, what's hard is determining whether that stationary object is directly in front, or off to the side. Cars are always passing stationary objects on the sides.

I would have thunk that to be a solved problem. Apparently not. https://jonathanwhiting.com/tutorial/collision/

And what's worse with systems like Tesla's autopilot, you don't have very much 2D resolution.

Re: Tesla crash in September showed similarities to fatal Mountain View accident

#553

Post by mirimir »

Tempest1981 wrote: post #164
Animats wrote: post #158

Earlier quoted context omitted.

But what amazes me is that Tesla autopilot apparently won't swerve or stop when it sees an unmoving object straight ahead. It won't even brake unless the thing in front looks like the back end of a car or truck. Even then, if it's stationary, it may still get hit. It won't swerve, ever; it has no logic for that. Four times that we know of, a Tesla has plowed into a vehicle partly blocking a lane. Putting something on…

Will it brake for pedestrians?

I doubt that it would.

But seriously, name "autopilot" aside, it's intended for divided highways. With high-quality road markings. And no stop lights.

And to be fair, airplane autopilots handle flying and landing. They don't handle driving between runways and gates.

Re: Tesla crash in September showed similarities to fatal Mountain View accident

#554

Post by Dylan16807 »

mdorazio wrote: post #535
Dylan16807 wrote: post #85

Earlier quoted context omitted.

> But once you do that, it gets tricky to determine when you should ignore the "stationary object" and when you shouldn't. That's not tricky. You never ignore it. A stationary object means that you will have to either stop or turn. You don't know which one yet, but you definitely know you'll have to take an action. If you haven't decided by some close point, you just pick one.

"Ignore" was probably the wrong word, but it is tricky. Remember that a vehicle is evaluating the environmental state at a given point in time to make decisions. Let's take the example of everyday driving on the freeway where you are following a car going the same speed as you. From your car's radar and camera perspective, the vehicle in front of you is stationary. It's not until you combine that information with add…

Don't make it sound like subtracting your own velocity is anything but trivial. Your whole first paragraph is playing semantics about the definition of the word "stationary". If the camera says you have zero relative velocity, that is not it saying "stationary", and you are not ignoring a "stationary" object.

> Combine that with the normal event of a garage wall or building directly in front of you while parking and we have three different "stationary object in front" situations that all have to be handled differently. In all three, the radar and camera are saying "stationary object ahead". But in the left-turn-with-wall situation you need to turn instead of stop. In the following-another-car situation you do nothing, and in the parking situation you need to stop instead of turn.

If the object is stationary, you turn-or-stop. If it's another car, it's really easy to measure that it's not stationary. If your sensors can't figure out the distance or velocity for multiple seconds in a row, your equipment should not be allowed to drive.

> highly complex model with corner cases and potential bugs everywhere

That's all in object detection, though. And none of that noise looks at all like a solid object at a specific location.

> If it was easy we would have had self-driving cars a decade ago.

I disagree. Even if you have a system that competently avoids stationary-object collisions, you're nowhere near a full self-driving car.

And while the overall problem of avoiding collisions has hard parts, none of the hard parts are in the "What do we do about a stationary object?" logic.

Re: Tesla crash in September showed similarities to fatal Mountain View accident

#555

Post by mdorazio »

mirimir wrote: post #551
mdorazio wrote: post #535

Earlier quoted context omitted.

"Ignore" was probably the wrong word, but it is tricky. Remember that a vehicle is evaluating the environmental state at a given point in time to make decisions. Let's take the example of everyday driving on the freeway where you are following a car going the same speed as you. From your car's radar and camera perspective, the vehicle in front of you is stationary. It's not until you combine that information with add…

There's some confusion about what "stationary" means. I was using the external reference frame. So I called road signs etc stationary. But in the vehicle's reference frame, road signs etc have closing velocity. Vehicles in front moving at the same speed aren't stationary in the external reference frame. They're stationary in the vehicle's reference frame. If one stops, though, it becomes stationary in the external re…

You're not being pedantic - it's an important distinction. That's why I've been putting "stationary" in quotes the whole time. An individual sensor has no concept of a reference frame, only the broader ADAS/autonomous system does. That's why acting on object detection is non-trivial - individual sensors report "object" with no context and it's up to fallible algorithms to make sense of often conflicting information.

Re: Tesla crash in September showed similarities to fatal Mountain View accident

#556

Post by [deleted] »

YeGoblynQueenne wrote: post #550
stale2002 wrote: post #503

Earlier quoted context omitted.

> Basically, forcing people to die in one specific way stinks to high heaven Then these people should stop trying to force me to accept a less safe method of transportation, by preventing me from using new technology! Yeah, those people shouldn't be forced to use a self driving care. As they are ALREADY not being forced to do. Nobody is being forced to use the technology. Just don't use it if you don't like it. It is…

The technology is not yet safe, as should be evident by now. It's being promoted as safer than humans, but it's not anywhere near that, yet, mainly because to drive safely you need at least human-level intelligence. Even though humans also drive unsafely, they have the ability to drive very, very safely indeed under diverse conditions that no self-driving car can tackle with anything approaching the same degree of si…

[deleted]

Re: Tesla crash in September showed similarities to fatal Mountain View accident

#557

Post by mdorazio »

Dylan16807 wrote: post #554
mdorazio wrote: post #535

Earlier quoted context omitted.

"Ignore" was probably the wrong word, but it is tricky. Remember that a vehicle is evaluating the environmental state at a given point in time to make decisions. Let's take the example of everyday driving on the freeway where you are following a car going the same speed as you. From your car's radar and camera perspective, the vehicle in front of you is stationary. It's not until you combine that information with add…

Don't make it sound like subtracting your own velocity is anything but trivial. Your whole first paragraph is playing semantics about the definition of the word "stationary". If the camera says you have zero relative velocity, that is not it saying "stationary", and you are not ignoring a "stationary" object. > Combine that with the normal event of a garage wall or building directly in front of you while parking and…

Subtracting your own velocity from what? I've been talking about individual sensor reporting with conflicting information and the complexity of decision making that results. A radar return from a rear bumper at relative zero miles an hour is exactly the same whether the car is actually in motion or not. Reference frame and velocity relative to the ground is up to your software algorithms to determine, not the sensors, and I've been trying to explain why that's non-trivial and "stationary" is always relative to something. You seem to be treating the entire system as an always-in-consensus whole, which it isn't.

I feel like we're just going in circles here. I could keep giving you examples of cases where sensors will report conflicting information that makes decisions like turn or stop difficult or false-positive prone, and you'll keep insisting that it's just object recognition and you should always know to turn or stop. I'll stop here and stand by my original point - sensor limitations and immature algorithms are the reason for issues like the ones Autopilot has; completely preventing these issues is not straight forward.

Re: Tesla crash in September showed similarities to fatal Mountain View accident

#558

Post by dllthomas »

dragonwriter wrote: post #531
pjkundert wrote: post #530

The root problem (as described by Taleb in "Skin In The Game", is: not all statistical probabilities are "ergodic" -- have no risk of Ruin or Extinction. The problem with saying that "our automatic driving system is much better than the average driver" and thus you should be good with allowing our system to drive, is that you are not exposed -- serially -- to the whims of some average driver. One "average driver" mis…

> So; since automatic driving systems are non-ergodic, they must be dramatically better (ie. orders of magnitude better) than the "average driver" to be considered viable. The risks from human drivers are also non-ergodic, so that suggests that if automatic driving systems are even minimally better than the average driver you should demand that every other driver be replaced with them without delay, because you will…

> human drivers all think they are far above average. And that’s the real problem.

This is often a joke, and there's some truth to it - people are often overconfident. But there certainly are individuals who think they are below average. It might be rare and still a market.

Re: Tesla crash in September showed similarities to fatal Mountain View accident

#559

Post by hndamien »

ggg9990 wrote: post #539
jacquesm wrote: post #467

Earlier quoted context omitted.

The reason why people buy expensive cars is because it is one of the ways in which they can quickly and quietly signal wealth or status. Cars are classicist, like it or not. After all, how much better can a $500K supercar be compared to a $50K car? Definitely not ten times better, the speed limits are the same, seating capacity is likely smaller, there may be a marginal improvement in acceleration and a corresponding…

Some of us just really like nice cars without signaling wealth. I recently bought a Hyundai Genesis even though I liked and could afford the better Mercedes Benz because I preferred to have a non-luxury brand. It's a New England thing.

I went from a two door Hyundai Getz to a Tesla because I wanted an electric car. Not to signal anything. I also couldn't wait for the Model 3 to come to Australia due to a growing family and a 4 door requirement.

Re: Tesla crash in September showed similarities to fatal Mountain View accident

#560

Post by Dylan16807 »

mdorazio wrote: post #557
Dylan16807 wrote: post #554

Earlier quoted context omitted.

Don't make it sound like subtracting your own velocity is anything but trivial. Your whole first paragraph is playing semantics about the definition of the word "stationary". If the camera says you have zero relative velocity, that is not it saying "stationary", and you are not ignoring a "stationary" object. > Combine that with the normal event of a garage wall or building directly in front of you while parking and…

Subtracting your own velocity from what? I've been talking about individual sensor reporting with conflicting information and the complexity of decision making that results. A radar return from a rear bumper at relative zero miles an hour is exactly the same whether the car is actually in motion or not. Reference frame and velocity relative to the ground is up to your software algorithms to determine, not the sensors…

> Subtracting your own velocity from what?

You said the camera/radar would be reading another car as "stationary", which is a velocity number of zero. Add/subtract your speed and you get the real speed.

A non-defective sensor suite is going to give you either distance or velocity, and you can use distance measurements to calculate velocity really easily.

> A radar return from a rear bumper at relative zero miles an hour is exactly the same whether the car is actually in motion or not.

Doppler effect.

> "stationary" is always relative to something

Once you have a velocity number, no matter what it's relative to, it's trivial to convert it to any reference frame you want.

> I feel like we're just going in circles here. I could keep giving you examples of cases where sensors will report conflicting information

That's because such things are irrelevant to my argument. I'm only talking about how algorithms should handle objects that have already been found.

> I'll stop here and stand by my original point - sensor limitations and immature algorithms are the reason for issues like the ones Autopilot has; completely preventing these issues is not straight forward.

I fundamentally disagree that the navigation algorithms are difficult here. Sensor issues are huge, but your original scenario was based on the sensors working and navigation failing. That specific kind of navigation failure is utterly inexcusable. It is actually easy to force a car to either slow down or turn to avoid a known obstacle. That specific part should never ever ever fail. It doesn't matter how hard other parts are.

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