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Interesting project! I had fun playing with it. I wanted to test the theory (which I saw in an article posted here on HN a few weeks ago) that a single car slowing right down on a busy highway (e.g. to avoid hitting an animal on the road or similar) can actually cause a traffic jam that goes back miles and can last for hours.

I couldn't prove that hypothesis at this scale. I am assuming that the AI drivers have just too good a reaction time and they can co-ordinate their speeds to each other to keep things moving along fairly nicely. A thumbs up for robot driverless cars, I guess ;-)

EDIT: Actually, playing some more - it does prove it to some extent. If you increase reaction time to ~800ms and let the traffic blitz along at a steady clip, then slow down two cars side by side to almost a stop, then after the initial cascade of accidents, it take ages for the traffic to get back to the same steady pace. Interesting.



The 200ms default reaction time in the simulation is wildly optimistic. I remember 1500ms from rider training and http://www.visualexpert.com/Resources/reactiontime.html seems to bear that out.


also braking: it looks like the cars can only brake as fast as they accelerate. seems like this should be a different slider.




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