Hello,

I am currently modeling a 3-leg roundabout, with two entering and exiting lanes on each approach .
I was having an issue with getting the vehicle path for my right SB lane to continue thru the roundabout. Therefore, all thru vehicles were utilizing the left SB lane and all right-turning vehicles the right SB lane.
I read through the additional documentation on multilane roundabouts and realized that the circle size/median width affected the vehicle paths. I then adjusted the median width and finally was able to get the program to produce a right-turn AND thru path for my right SB lane. However, the simulation continues to operate incorrectly. The thru vehicles continue to ONLY use the left SB lane, even though the right SB lane shows a viable thru path. There are even instances of thru vehicles traveling in the right SB lane and then stopping & waiting (while also holding up the right-turning vehicles traveling in that lane) to merge to the left SB lane in order to go thru the roundabout. Why are these vehicles not just continuing thru the roundabout via the right SB lane as the vehicle path would suggest? Am I missing something obvious??
NOTE: I've provided the attached screenshot to better visualize. You can see in the screenshot a white vehicle AND a white truck trying to merge to the left in order to go thru the roundabout.
Thank you.

SimTraffic,_Screen_Print.pdf (151 KB, 49 downloads) SimTraffic Screen Pring

Hi trc,

Do you mind creating a support ticket and attaching the Synchro (SYN) file? I might be able to make some suggestions based on seeing the file.

Thanks,

John.

this is interesting. I was able to make replica using your picture as a guide and get it to operate. I didn't realize that the lane alignment in synchro roundabouts was dependant on approach median width and central island diameter.