MetropAccess-Digiroad tool – WHAT IS IT?
MetropAccess-Digiroad tool is a tool for measuring accessibility by car. Realistic driving times for private cars and the whole travel chain (“door-to-door approach”) are taken into account in the calculations.
Realistic driving times are taken into account by modifying the speed limits in the road network. Travel times of the road segments are made more realistic by adding crossroad impediments for different road classes. The work is based on floating car measurements conducted in the Capital Region of Helsinki (data from the Helsinki City Planning Department and Helsinki Regional Transport Authority HRT).
The door-to-door approach is implemented by taking into account the time required for parking:
- walking time from the real origin to the nearest network location
- average walking time from the origin to the parking lot
- travel time from parking lot to destination
- average time for searching a parking lot
- walking time from parking lot to nearest network location of the destination and
- walking time from network location to the real destination
A more detailed description of the method can be read from the Master’s Thesis (Pro Gradu) by Timo Jaakkola: GIS-based method for modeling drive and travel times – example of the Helsinki Metropolitan Area. (full text only in Finnish)
Digiroad data (k-edition) provided by the Finnish Transport Agency can be used as input network dataset for the Digiroad-tool.
The MetropAccess-Digiroad tool is composed of several sub-processes listed in the following table. Steps 1-3 are used for modifying the Digiroad data; the crossing impediments are added into the attribute table of the Digiroad dataset. Step 4 is used for calculating travel times and distances between a set of points, and step 5 is used for calculating service areas for selected points. You can skip steps 1-3 if you already have a modified network dataset.
|Step||Tool name in Finnish||Description|
|1||Vaihe1_LäpiajoaikojenLaskenta||Calculation of drive-trough times for road segments|
|2||Vaihe2_NetworkDatasetinLuonti||Creating the Network Dataset|
|3||Vaihe3_AikasakkojenLaskenta||Calculating the impediments based on crossings, traffic lights and ramps for different times of the day.|
|4||Vaihe4_KokonaismatkaketjunLaskenta||Calculating the travel chain (routing) between selected origin and destination points.|
|5||Vaihe5_PalvelualueLaskenta||Calculating the service area for selected points.|
See more details of the outputs in the description of the MetropAccess-Digiroad data.
DOWNLOADING THE TOOL
The most recent version MetropAccess-Digiroad tool is implemented in ArcGIS 10.2 software version (see note on the functionality below). Earlier versions of the tool are available in ArcGIS 10.1 and ArcGIS 10.0. The tool requires that the Network Analyst extension is activated in ArcGIS.
BETA: Download version for ArcGIS 10.2: MetropAccess-Digiroad_ArcGIS_10.2.zip
Note: This tool works only for door-to-door routing and service area calculation (steps 4 and 5). Modifying the network dataset (step 3) is not currently working in ArcGIS 10.2. You can download the modified Digiroad network dataset for the Helsinki Region, and use that as input for step 4 (“Vaihe_4_KokonaismatkakethunLaskenta.py”) and step 5 (“Vaihe_5_PalvelualeLaskenta.py”).
Download version for ArcGIS 10.1: MetropAccess-Digiroad_ArcGIS_10.1.zip
Download version for ArcGIS 10.0: MetropAccess-Digiroad_ArcGIS_10.0.zip
The Toolsets include:
1) Documentation and licensing information
2) MetropAccess-Digiroad tool (ArcGIS Toolbox and script files).
All MetropAccess-Digiroad toolkit products are licensed under the GNU General Public (v3) license, which allows the manipulation and development of the tools (even commercially), as long as the new outputs are licensed under the same terms.
Detailed license information are available in the download package of the tool.
If you use our data or tools in your analysis, we encourage you to cite properly to our work. Description of the MetropAccess-Digiroad tool is included in the following publication:
Toivonen, T., M. Salonen, H. Tenkanen, P. Saarsalmi, T. Jaakkola & J. Järvi (2014). Joukkoliikenteellä, autolla ja kävellen: Avoin saavutettavuusaineisto pääkaupunkiseudulla. Terra 126: 3, 127-136.