In the framework of the New Work Item Proposal 22953 eXtended Geographic Data Files (XGDF) of ISO TC 204/ CEN TC 278 the existing standard ISO 14825 on road data bases will be extended, such that the integration of traffic sign data will be supported. The research project aims at accompany this extension of the standard and to guarantee that the matter of traffic sign data integration is considered properly, including the specific Swiss requirements. Furthermore compatibility of the modified location referencing methods with those methods used in Switzerland (especially those of the research project mentioned and of the project MISTRA) will be observed.
The aim of this research project is the elaboration of a framework for the integration of traffic signs in Swiss road databases for applications enhancing traffic safety using advanced driver assistance systems and for better planning and maintenance of traffic signs, based on the extension of the ISO 14825 standard, under consideration within ISO TC 204/ CEN TC 278 as expressed in the New Work Item Proposal 22953 (eXtended Geographic Data Files XGDF).
Traffic signs and road markings is an important information of the traffic domain, especially to enhance the safety of the traffic operation. So far this information is only available on roadside panels or applied to the road surface respectively. If the information would also be accessible as electronic data in a road database, including appropriate referencing to the road network, it could be used for new applications in the intelligent transport systems (ITS) domain with the focus on road safety, especially for advanced driver assistance systems in the vehicles. This research study investigates how to set up such a data base, what could be the structure of such a data base and what benefits would result out of it.
An inventory shows that today there is no adequate basis for traffic sign data in the road transport domain, which could be used for the intended applications. In addition to the ITS domain just mentioned, such applications could be found in the framework of an electronic traffic sign register, facilitating the management and maintenance of the traffic signs at the responsible road authority.
The first step towards a traffic sign database was a comprehensive collection of the existing signs. Several options for this are presented and it is shown that the mobile mapping technology opens an interesting new perspective. In the framework of the research project practical experiments with picture sequences from mobile mapping were carried out. The focus was on the possibility to identify the traffic signs with automatic traffic sign recognition.
Before adding the traffic signs to the database, they have to be validated. With this, errors in the collection process and inconsistencies of the existing signs become visible. The possible inconsistency checks are presented in detail.
Once the data are stored in the database, they are only usable in long term if they are regularly updated. The investigation shows that updating consists of a long sequence of interacting processes and that the monitoring, meaning the process of finding out where changes of traffic signs are intended, is a key element for the management of the database. In any case the responsible road authority should take part in this process.
But which data on traffic signs and road markings are to be included in the database? The answer is given with a proposed specific data model with the special of mapping traffic signs and road markings to a traffic signaling, having a defined spatial and temporal va