Ludwigsburg - a full fleet deployment in Germany
Mid-size city, large project
Highlights of the project
- Public transport priority system (OBUs) using R09 payload in the CAM messages
- Connection to a third-party board computer using IBIS-IP (VDV-301-2)
- OBU controls priority by itself, based on data from the board computer and own configuration
- Additional 20 units delivered to be used for emergency vehicle priority
- More than 30 000 priority requests per day
Communication with the board computer
The board computer by IVU communicates with the OBU using the protocol IBIS-IP – that is, according to the norm VDV 301-2. The service used is CustomerInformationService. Our OBU supports all features of IBIS-IP, mainly the DNS-SD service announcement.
Configuration of the priority points
In this project we encountered a common issue: the priority points (“Meldepunkte”) are stored in the board computer and there is no way how to get them via a communication interface.
To get the points to OBU, we had to process the configuration data from the board computer. The configuration data is stored in a form of traveled distance between stops. As V2X is dependent on GNSS coordinates, we first projected the traveled distances on a geographic route of the public transport line or connection. By combining several sources, we succeeded in getting a complete configuration of all priority points to the OBU.
Now, the vehicle, based on its line number, selects the correct priority points for given maneuver in the intersection.