I am trying to simulate a 4-lane freeway offramp where the left 2 lanes turn left and the right 2 lanes turn right at a signalized intersection at the end of the ramp. The ramp is about 500 m long, but traffic is often heavy enough that queues can fill the entire ramp. Traffic comes from 2, 2-lane highways and there is a significant amount of "weaving." Real drivers know which way they want to turn and merge into the appropriate lanes well before the traffic signal. SUMO vehicles, however, often seem to wait too long, and as a result, end up at the intersection in the wrong lanes which causes gridlock. I've tried putting additional zipper junctions within the onramp to "encourage" vehicles to get into their proper lanes but that still doesn't work all the time.
How far in advance do SUMO vehicles start planning to change lanes ahead of an intersection and is there a way to adjust this parameter?
By the way, this is a real road. You can see it on Google Maps at (N 37.410905090334374, -122.07430147214615).
Thank you for any suggestions you might have!
Albert Jeans