Get the most out of PTV Visum 15! In our blog post series “Excited about PTV Visum 15”, Michael Oliver, Solution Director PTV Visum, will share his tips and tricks, using new features and functionalities of the world’s leading transport planning software.
The use of GPS data for transport modelling is becoming more common. In most cases the data is obtained from data providers such as TomTom, INRIX and Here and is pre-processed to be provided as origin-destination matrices or link data such as speed profiles.
This is an attractive option as it provides data with a high volume of observations at a reasonable cost, and PTV are providers of such data in Visum files. But let’s say you want to collect and process your own GPS data, for use in research, or in other applications, or because processed data is not so readily available in your part of the world. Then for this you can use PTV Visum 15 and the new GPX import function.
GPX, or GPS Exchange format, is a form of XML designed as a common format for GPS data, and describes so-called ‘waypoints’, ‘tracks’ and ‘routes’. GPX data can be exported from GPS devices such as smart-watches, smart-phones and navigation devices.
Importing the GPX files in to PTV Visum is done through the user interface, with the GPX routes being created as paths which can be automatically snapped to a road network (which could be an existing model, automatically imported from OpenStreetMap or purchased from a data provider via PTV). Once this data is inside Visum then users can begin using the data, for example, to calculate observed link travel times or to compare modelled and observed route journey times.
In the example shown in figure 1, GPX data has been obtained from the internet, imported and snapped to the underlying network. The data was recorded by people walking around in the city of Halle. Figure 1 shows how the routes are visualised in Visum, and Figure 2 shows how the data can be analysed at the link level. Figure 3 shows how the new reporting tool in Visum 15 can be used to compare modelled and observed route journey times.
Next week you will learn more about GIS functionalities in PTV Visum.
This post is also available in: German