The Merge and Exit Assistant – a Galileo-based ADAS application developed within the project FAMOS

Kurzfassung

The research project FAMOS (Galileo for Future Automotive Systems) illuminates the potentials of the European Satellite Navigation System Galileo for the application in the context of advanced driver assistance systems (ADAS). An essential objective of this project lies in the target-oriented integration of Galileo in a future safety and information concept for the automotive domain. In addition to the development of an adequate positioning platform, another focus lies on the design and development of three different ADAS applications. These applications are to be integrated into a test vehicle for evaluation under real conditions in a Galileo test bed. One of these applications is a Merge and Exit Assistant which is discussed in this paper. The manoeuvres of merging onto and leaving a motorway belong to the most complex driving tasks to be found in traffic. They are characterised by a coordinated form of longitudinal and lateral driving procedures. The temporal and spatial constraints for these manoeuvres lead to high stress levels for the driver which can result in driving errors and safety critical situations. The demands will increase even more in the future since traffic is expected to intensify which will lead to an enhancement of the situation complexity. This motivates the development of an advanced driver assistance system focusing on the vehicle control and guidance levels referring to the three-dimension-model of vehicle guidance from Bernotat (1970). The aim of the Merge and Exit Assistant is to provide an accurate and safe transition onto the target lane for improving comfort and safety. For this purpose, the surrounding traffic is required to be monitored and the driving behaviour needs to be adapted according to the existing conditions concerning traffic and roadway arrangement. The main issue of development lies in the interaction between functional requirements based on the application concept and the resulting technical requirements, particularly the GNSSbased positioning. The initial point of development is given by the analysis of the driving tasks to be performed by the driver while merging onto and leaving the motorway. The manoeuvres can be divided into three fundamental stages. These stages are differentiated by roadway and manoeuvre attributes. For each of these stages an analysis of driving errors is conducted, which allows deducing several basic kinds of assistance. These are then integrated into an overall ADAS concept. This concept includes the support of both the longitudinal and lateral control for the entire manoeuvre and the lane change procedure in particular. In addition to this, four different configuration levels of the application are established. These range from basic functionality of an information and warning system via the generation of action recommendations to a semi-automated system. The latter comprises an automated longitudinal control while steering is performed manually by the driver. The levels differ in their complexity and the associated technical requirements concerning availability, accuracy, and integrity of the corresponding sensor information. The sensor information consists of the GNSS-based positioning platform and a digital map with all necessary roadway attributes combined with vehicular and environment sensor data. These data sources have to be fused in order to assure lane accuracy which is a general demand for the functional capability of the Merge and Exit Assistant. The paper gives an overview about the hitherto steps of development beginning with the functional definition of the application, followed by the formulation of a detailed design and the implementation process performed so far, finishing with an outlook on future work. This work was funded by the German Federal Ministry of Economics and Technology (BMWI). Project: FAMOS Galileo for Future Automotive Systems, FKZ 19S9007D.