OSM Import of New York’s Lower Manhattan

Starting a new Vistro network? Here are the top 5 time-saving advantages to use OSM data on your next model, regardless of your model size:

For larger networks – and those with many one-way streets – this import process can be a critical shortcut. In the example used for this blog post, I’ve imported 50 intersections and 220 links in less than 10 minutes, less than 12 seconds per intersection – and these intersections received all the import benefits described above!

Materials needed

So, you may be asking, “what will I need to import OSM into PTV Vistro?” First, you need to export reliable OSM data from a site like openstreetmap.org. Next, you will need PTV Visum to perform the bulk of the heavy lifting, prior to importing into PTV Vistro.

Steps

Step 1: Download your OSM data with the .osm extension from an external site.

OpenStreetMap.org export interface

Step 2: Import your OSM file into PTV Visum under the File menu (File/Import/OpenStreetMap…) by selecting your .osm file. In the dialog, select import an “urban road network”, and check the licensing terms. Click “Okay” to begin the upload.

PTV Visum OpenStreetMap Importer

Step 3: Delete extra Nodes and Links in PTV Visum that are not needed. This can be achieved by selecting the nodes and links and pressing the “Delete” key, or by holding the “Shift” key to delete multiple elements. When prompted, after deleting nodes between links, use the connect link option to retain the links. Deleting extra nodes is very important to reduce the number of converted junctions in Vistro.

Extra nodes that are not deleted from PTV Visum are converted to junctions in PTV Vistro

Step 4: Update the intersection traffic Control Types in Visum. To do this in bulk, click on intersections with similar Control Types, while holding the “Shift” key, then in the Quick View window, use the drop-down menu to select the correct Control Type. By right-clicking “Nodes” in the Network Toolbar, select “Edit Graphic Parameters” to turn on icons at intersections for Control Types, such as Two-Way Stop and All-Way Stop.

Selecting Intersection Traffic Control Types with Quick View in PTV Visum

Step 5: Edit link attributes in bulk. This is accomplished by right-clicking on Links in the Network Toolbar and selecting “List”. In the List, look at the “OSM_MaxSpeed” and update values, as needed. For example, change “50” to “30 mph” if the OSM data is not already in your working units. Next, click on the “OSM_MaxSpeed” header to select the column, copy (CTRL+C). Then, click on the “V0Prt” column header to select the column and paste values (CTRL+V). Individual links can be updated by selecting a link to update, and then editing attributes in the Quick View window. Using the “Select Attributes” button in the Quick View window, attributes, such as “Number of Lanes” can be selected, viewed, and/or modified.

Step 6: Remove extra polypoints from PTV Visum prior to conversion. Since OSM and PTV Visum use a node-link structure and do not take in account intersection width, polypoints may be inside or near the PTV Vistro intersection. Polypoints that are too close to a Vistro junction can cause an undesirable kink on the legs. Removing the polypoints in Visum will reduce a great deal of extra work in Vistro. To remove all extra polypoints, you can go to the Link list, select all links, then in the Network Editor, right click and select “Delete All Intermediate Points”. Alternatively, you can hold down the “Shift” key and select the links individually, prior to the right click.

Remove extra polypoints in PTV Visum to avoid leg kinking in PTV Vistro

Step 7: Save your .ver file and import it into Vistro. In Vistro, using the File Menu (File/Import/Visum), select your .ver file and click “Okay” on the Visum Import dialogs, ignoring the prompts to insert paths and volumes.

Results

Voilà, you now have a Vistro network within minutes! After you’ve completed this import, please, be aware that OSM is not a perfect data source and data quality highly varies from location to location. If you see areas that need improvements, updates can be made in the Visum file manually and then quickly reimported to a new Vistro file. The following items are typical elements that should be carefully reviewed: lane direction; speeds; lane width, pocket lanes; the number of lanes; lane configurations; stop bars for two-way stops, and conversions of barrier separated roadways.

Completed Vistro import in Cincinnati, OH, USA

And, that’s it! If you have questions or comments, please write me in the PTV Vistro Forum on LinkedIn.

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