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by jjulius 1038 days ago
>This is a technical use of the word "collides".

>... and was struck by the fire truck.

That's literally two things colliding, this isn't a "Well, OK, 'teeeeechnically', sure," situation at all.

>It is sad that automated cars are being asked to detect emergency vehicles at all.

>A system that signals the location of any actively flashing vehicles to all nearby automated cars is technically achievable.

Flashing lights mean different things depending on the light, the vehicle, and the situation - a construction vehicle with orange flashing lights is different from a police cruiser hauling ass up behind you, for instance. Drivers are responsible for discerning these differences, what makes automated cars different?
1 comments
jncfhnb 1038 days ago
Idk. If you say “two objects collided” that to me implies a mutual head on collision.

You wouldn’t say an object at rest collided with something else.

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jjulius 1038 days ago
>Idk. If you say "two objects collided" that to me implies a mutual head on collision.

The commonly used phrase for such a scenario is "head-on collision", while "collision" just means objects coming together with a solid impact - could be one object moving, could be both.

>You wouldn't say anything object at rest collided with something else.

No, but you'd say that the car collided with the tree rather than the tree and the car collided. In this specific instance, both cars were moving, and they collided with each other.

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jncfhnb 1038 days ago
I still disagree. Moving is not sufficient. If both are moving in the same direction and one hits you in the back, you would not say they collided with each other.

we define collisions by whether the velocity facing side of the object hits the object.

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SideburnsOfDoom 1038 days ago
> If both are moving in the same direction and one hits you in the back, you would not say they collided with each other

you are talking about a "Rear-end collision", correct? https://en.wikipedia.org/wiki/Rear-end_collision

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jncfhnb 1038 days ago
Yes. You would not say the lead car collided with the other in a rear end collision unless it was reversing.

> Typical scenarios for rear-ends are a sudden deceleration by the first car (for example, to avoid someone crossing the street) so that the driver behind it does not have time to brake and collides with it.

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