VISSIM 5.30-05 User Manual

Public Transport
6. If a departure time is defined for that stop, the PT vehicle remains at the
stop (after completion of passenger service) for that portion of the
remaining time until scheduled departure, which is defined by the slack
time fraction.
6.5.2.7 Variation of Arrival Times
In reality, PT vehicles do not enter the simulated network section exactly
according to schedule. Their network entry is randomly distributed around
their scheduled time (e.g. ±1 min). In order to model this random arrival in
VISSIM, follow the instructions below:
1. Create a dummy link at the beginning of the PT route (typically on the
dedicated link) and use the PT line number as link number, if possible.
Make sure that the length is sufficient (50-100m due to vehicle length
and speed) so that the PT vehicle can enter the network on this link and
safely stop. Connect the dummy link to the link network.
2. Create a dummy PT stop on the dummy link. It should start at 25 m or
more and its length should exceed the PT vehicle length. For numbering,
use the line number as stop number, too. This dummy stops makes it
possible to model deviating times of arrival for PT lines which enter the
VISSIM network.
3. Include the dummy stop in the line oute and assign a dwell time
distribution to the dummy stop. For example, a mean value of 60
seconds and a standard deviation of 20 seconds could be chosen. The
actual departure time at the dummy stop would then be normally
distributed between 0 and 2 minutes (99% value).
4. Consider the dwell delay at the dummy PT stop (average dwell time of 60
sec) for all other scheduled departure times.
User Manual © PTV AG 2011 257