Importing routes

If your Vissim network is based on the data of an ANM import, you can calculate a PrT assignment for the original Visum network, select the demand segments of your choice, and export intermediate point coordinates and other data to a *.rcf file. Select this file in Vissim and import the content into the Vissim network. Based on the data, Vissim defines network objects for vehicle routes.

Data stored in the *.rcf file

Visum stores the following data in the *.rcf file when routes are exported:

• Numbers of the zones in which routes begin and end
• Coordinates of the link polygons In the Vissim network, Vissim can allocate links whose positions differ from the world coordinates of a point in the *.rcf file by the value of the parameter Snap radius (default value 80 m) (Importing the *.rcf file).
• Volume for each vehicle route
• Vehicle types
• Projection information

For information on exporting routes from Visum, refer to the Visum manual.

Use cases for route import

• Initial route import: You import the route into a Vissim network based on ANM import data. The ANM import data includes a Vissim network without zones or vehicle route-specific network objects, such as static vehicle routes, static vehicle routing decisions, vehicle inputs. When dynamic assignment is performed, for OD matrices, parking lots,zones and the path file *.weg. An initial route import defines these network objects in the Vissim network. In the network editor, Vissim also creates cross-sections for static vehicle routing decisions and vehicle inputs on links and connectors and allocates zones to the following network objects based on the zone numbers in the *.rcf file:
• for static vehicle routes in the Destination zone attribute
• for static vehicle routing decisions in the Zone attribute
• for vehicle inputs in the Zone attribute

When importing routes, you allocate vehicle types from Visum to vehicle types in Vissim.

You can also carry out an initial route import if after the ANM import into the Vissim network, you already defined vehicle route-specific network objects and allocated them to zones. If the numbers of the zones allocated to these network objects and the position of the network objects in the Vissim network match the coordinates in the *.rcf file, the network objects are retained in Vissim.

• Re-import routes: You can repeat a route import, for example, because in Visum you used different parameters to calculate the PrT assignment, which resulted in new volumes that you want to assign to the vehicle inputs in the Vissim network. Since in this case, the vehicle routes, vehicle routing decisions and vehicle inputs have either been defined and assigned through the initial route import or manually by yourself, Vissim updates the vehicle route-specific network objects in the network that match objects in the *.rcf file when the route is re-imported. To identify objects from the *.rcf file and their corresponding objects in the Vissim network, Vissim uses the number of the assigned zone, the position of the network object in the Vissim network and the coordinates in the *.rcffile.

You can also choose to have Vissim define new vehicle route-specific network objects and their cross-sections in the Vissim network, if the Visum network or the Vissim network have been changed in such a way that an allocation to existing network objects is no longer possible, but new vehicle routes, vehicle routing decisions and vehicle inputs or zones are defined and vehicle route-specific network objects can be allocated to zones.

Conditions and restrictions for route import

You can import the *.rcf file via initial route import or via a re-import of routes under the following conditions:

• The Vissim network is larger than the Visum network.
• The Vissim network was edited after the original ANM import.
• The node numbers of the Vissim network and Visum network differ from each other.
• If in the Vissim network, zones have already been defined that have the same number as the zones in the *.rcf file, Vissim allocates these zones to the network objects.

For the position of the coordinates, Vissim takes data from the Visum network, available through projection, into account.

Desired speed distributions at parking lots

If you have assigned vehicle compositions to parking lots that use new vehicle routes, these vehicle compositions will be deleted through route import. As a result, at these parking lots, the desired speed distributions of the vehicle types assigned to these vehicle compositions are also lost. If you need desired speed distributions at parking lots, define the desired speed decision in the Vissim network downstream of the respective parking lot. Assign the desired vehicle class and desired speed distribution to the desired speed decision.