[Jonnerz]

You could say the same for trains though - they follow a track in a similar sense to Tesla's autopilot. Someone could perform a "prank" by putting something on the track in order to derail a train. How often do you see that happen? Painting a line on the road is obviously easier to do, and could also happen by accident, but I think the chances of any danger are extremely low.

Hopefully when we start removing the driver from cars with autopilot, they will be following some sort of under-road NFC-like guidance system rather than painted lines.

[falcolas]

There’s a theory out there that a penny on a rail can derail a train. You wouldn’t think people would do such a thing, with such disastrous consequences... but they do. Thousands of times a year.

Actually derailing a train takes serious effort; but people still try constantly. Derailing a Tesla seems somewhat easier, so I guess we’ll see.

[nugi]

On youtube there are old black and white films produced to show the result of rail sabatouge. Even with a foot cut from the track the train did not derail. Quite impressive. I used to flatten coins as a kid all the time by leaving them on the tracks.

[simion314]

It is much harder/expensive to place a big truck on heavy object on a train track then painting a line. The trains also have a driver that will try to stop the train so reduce the impact.

This self driving cars can be tricked by bad conditions or some optical illusions, like you have a t-shirt with some pattern on it and the Tesla car will coma and hit you