Selecting network settings for vehicle behavior

1.  On the Base Data menu, click > Network Settings.

2.  Select the Vehicle Behavior tab.

3.  Make the desired changes:

Element Description
Speed limitation in curves

 If this option is selected, vehicles approaching link intermediate points will brake according to the Brake radius reaction (Attributes of links). This means they will not exceed the acceptable speed as per the Desired curve speed function of their vehicle type (Attributes of vehicle types). Radius calculation is based on several successive link intermediate points. These can also include the start point and end point. For a connector, the points of the From-link and the To-link can also be included in the calculation. Vissim calculates the radius for the center of the links, regardless of the number of lanes.

The speed limitation does not apply to vehicles driving backwards.

Using an attribute in the network file of a Vissim version prior toVissim 2023

If you read in a network file of a Vissim version prior to Vissim 2023 and select this attribute, check the following:

  • Appropriate curve speed functions must be defined. Appropriate default curve speed functions are saved to the defaults.inpx file from Vissim 2023 and higher. From this file you can read curve speed functions additively (Reading a network additionally).
  • A desired curve speed function must be assigned as an attribute to the relevant vehicle types.
  • Check whether reduced speed areas in your Vissim network are no longer necessary due to the speed limit in curves and whether it makes sense to remove these reduced speed areas.

Link gradient based on

  • Attribute 'Gradient': For driving behavior, the static gradient entered for the link during simulation is used. The z coordinates of the link section are ignored.
  • Z-coordinates: If this option is selected, during simulation the current gradient for driving behavior is always calculated from the z-coordinates of the link section on which the front edge of the vehicle is located. The given static gradient of the link is thereby ignored.

Note: When selecting the option Z-coordinates, make sure there is no connector, connecting links with a large difference in altitude (e.g. 0.5 m) over a very short distance (e.g. 1 m).

Traffic regulations

Controls the creation of opposite lanes, bus bays, and the driving behavior on freeways with a right/left side rule based on the selected traffic regulation:

  • Right-side traffic
  • Left-side traffic

If you change the traffic regulations and under Driving behavior, Lateral behavior, Desired position at free flow, the attribute values Right or Left are selected, Vissim will change the attribute value Right to Left and Left to Right (Editing the driving behavior parameter Lateral behavior).

Specific power for HGV

Power-to-weight ratio of vehicles of the category HGV in [kW/t], with t = metric ton:

  • Minimum: Lower limit of specific power. Default: 7.00, value range 1 to 10
  • Maximum: Upper limit of specific power. Default 30.00, value range 11 s to 1,000

If you change the settings, the simulation results change even if there is no vehicle that has exceeded the upper limit or fallen below the lower limit. Vissim uses the upper and lower limits for interpolation. Then the maximum acceleration for all trucks can change and thus the simulation results.

Superordinate topic:

Selecting network settings