Attributes of vehicle inputs

The Vehicle Inputs list opens automatically when you insert a network object and have selected to automatically have a listed opened after object creation (Right-click behavior and action after creating an object). By default, only the Vehicle Inputs list is opened.

1.  Select Private transport > Inputs in the Lists menu.

The Vehicle inputs list opens.

By default, you can edit the list (Using lists).

The attribute and attribute values of this network object type are shown in the list on the left, which consists of two coupled lists.

Tip: To open coupled lists for a network object type, on the Lists menu, click > <Name network object type>.

The list on the left may include the following attributes:

Column Description
No

Unique number of the vehicle input
Name Name of vehicle input
Link Name of the link to which the vehicle input was added
Volume Volume: Number of vehicles per hour - not per time interval
VehComp

Vehicle composition per hour - not per time interval (Modeling vehicle compositions)

2.  If you want to change the time intervals for a vehicle input, right-click the desired entry in the Vehicle Inputs list.

3.  On the shortcut menu, click Edit Time Intervals.

The Time Intervals list opens (Defining time intervals for a network object type).

Note: In lists, you can use the  Attribute selection icon to show and hide attribute values (Selecting attributes and subattributes for columns of a list).
Showing and editing dependent objects as relation

1.  In the list on the left, click the desired entry.

The list on the right contains attributes and attribute values of network objects, and/or base data allocated to the network object selected in the list on the left (Using coupled lists):

Vehicle Volumes By Time Interval list

1.  Enter the desired values.

Element Description
Cont

Continued: Adopts the volume of the previous interval, if several time intervals for vehicle inputs have been defined. The first time interval is therefore always deactivated. The cells are white and the values are valid for this time interval only.

  • The option is not selected: The cells are white and are only valid for this interval.
  • The option is selected: The cells Volume, VehComp and VolTypeare gray and are valid for the period of the combined intervals. Only the last cell, for which the Cont attribute is not selected, can be edited. When this option is selected, a change in volume is adopted for all the following cells.
TimeInt

Time interval: Start and end of the interval in simulation seconds (Defining time intervals for a network object type).
Volume

Volume per time interval (number of vehicles per hour)
VolType

Volume type:

  • Stochastic: Stochastic fluctuations of the traffic volume may occur. Vissim determines the average gap between two vehicles from Volume / Time interval length. This average gap is used as an average value of a negative exponential distribution from which Vissim draws the gaps. This is equivalent to a Poisson distribution of the input times. The gap can be as small as zero and arbitrarily high, but with decreasing probability the further the gap is from the average value. The actual input volume results as the total number of these time gaps. The deviation from the given value is not limited by any specific percentage. In real life scenarios, the entry time may be subject to greater variability than in Vissim on the basis of the Poisson distribution.

The cells are white.

  • Exact: based on the volume (vehicles/h / 3600 x time interval length), Vissim calculates for each of these vehicles a random input time in the time interval at which the vehicle enters, unless prevented by one of the following factors:
  • a congestion downstream of the vehicle input
  • The calculation of the random input times of the vehicles results in too many random input times at the end of the time interval, so that individual vehicles cannot enter in the current time interval, but only in the following.

The cells are yellow.

If in addition, the Continued attribute is selected, the exact number of vehicles is generated for the entire period, which is made up of all time intervals. If the Continued attribute is not selected, the exact number of vehicles is generated in each time interval.
VehComp

Vehicle Compositions (Modeling vehicle compositions)

2.  If you want to allocate additional volumes to other intervals for the selected vehicle input, right-click in the Vehicle Volumes By Time Interval list.

3.  On the shortcut menu, click Add.

The next defined time interval will be added.

4.  Enter the desired values.

Superordinate topic:

Modeling vehicle inputs for private transportation

Information on editing:

Defining vehicle inputs