[sumo-user] Departure speed is incorrect

[Do Duc Le <doducle@xxxxxxxxxx>]

Hello,

I control the speed of my vehicles via Traci with vehicle.setSpeed(), 
which I'm reading from a file. After I ran the simulation I noticed that 
the vehicles didn't behave as expected. The depart times of the vehicles 
(which were specified in the route-file) changed. Some vehicles entered 
the network way later than specified. I did some tests and it seems like 
the lane must be free for several meters in front of the depart position 
before one vehicle can enter the network.

In my example i have a single straight lane and all vehicles enter at 
the same position at the beginning of the lane. My vehicle 'A' enters 
the network, but slows down, so that at the time the next vehicle 'B' 
enters, 'A' has only driven a few meters and is still quite near to the 
beginning of the lane (but there is still more than enough space to 
avoid a collision). What I observed is that 'B' now does not enter at 
its specified departure time, but about 4 seconds later.

Has anyone of you experienced this problem? Is there an option to 
disable this behavior? How can I fix this?

Thanks in advance.

Best regards,

Duc