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Comment by SovietDissident | Hacker News Reader

Neat. Question: what happens if there's a car in back of the Tesla? Does does the Tesla disregard him and whether or not he has time to stop as well?

Edit: Certainly the top priority is avoiding the car in front of you, and you should slam on the brakes to do it. However, once you stop, the Tesla should release the brakes (if there's an imminent collision from the rear) to minimize the impact to the Tesla driver and the car slamming into the back of him. Would be cool if the Tesla engineers added this (if feasible).

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I would assume so. If you are following someone, it's your responsibility to have enough leeway to stop if they stop suddenly. And it's much less dangerous to be rear ended than it is to hit something head on.

Fast breaking removes energy from the collision and if someone is not paying attention there going to hit you anyway.

If your going to respond the the car behind you then it's much better to simply slow down if your being tailgated. Doing anything else is counter productive.

PS: Even a long line of tailgating cars can stop because you can only use the space between you and the obstacle, but the car behind you get's that same distance plus the distance between you at them. This space keeps stacking as you go further back so by 10 cars or so it's a long slow break.

Though the "buffer" gets eaten-away with every added car that has to wait for the one in front of them before they can "react". Assuming they don't see past the car in front of them.

Your model suggests we should get thousands of car pileups if anyone does heavy breaking in bumper to bumper traffic. Clearly that does not happen.

The reason is the buffer between you and the car in front of you is eaten by the difference in your speeds. Going from 80MPH to 70 MPH takes ~0.7 seconds, where starting to break takes ~0.2 seconds. Even if there is just 5 feet between cars the signal propagates plenty fast.

What do you mean by difference in speeds? The assumption I made, simplifying the thought experiment, was that the cars had a fixed-length between them, and they were all going at the same speed.

I don't know about other countries, but where I drive, not only the front is the top priority but it is your responsibility. If a car hits you from behind, it's their fault for all intents and purposes.

And slam into the other car? Don't you want to stop to reduce the energy in the crash? Perhaps turn a little to avoid being hit from behind? Is that your idea? Not stopping because the driver behind you isn't safely in control of the car and hitting someone in front of you might mean that someone's insurance company might find you at fault.

It would be prudent to do so, as head-on collisions are far more dangerous.

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