Calibrating Travel Times

Today we are continuing with the series of posts about calibrating SimTraffic. Travel times are often collected in the field and compared to the SimTraffic arterial report. If needed, speed can be calibrated either with the Link Speed in Synchro or the Speed Factor in SimTraffic.

The Link Speed controls the average desired speed for drivers in SimTraffic. Typically this value is set to the speed limit, but can be calibrated as needed. In Synchro, you can edit the Link Speed for each link individually.

The Speed Factor is multiplied by the Link Speed to obtain each driver's desired speed. By default, driver types 1-5 have a desired speed less than the Link Speed, and driver types 6-10 have a desired speed greater than the Link Speed. You can edit the Speed Factor for any or all driver types to calibrate travel times.

Remember that SimTraffic's Driver Parameters are applied globally throughout the network. The Link Speed may be a better setting to use if you are only needing to calibrate a specific section of a large network.

Also check out the other recent posts about calibration:

• ​Positioning and Mandatory Distances
• Lane Alignment
• Link OD Volumes
• Turning Speed