Towards Design and Integration of a Vehicle-to-X Based Adaptive Cruise Control

Today, assistance systems more and more rely on external environmental information. This information exchange is widely still limited to on-board sensors and the local area around the vehicle. Considering e.g. typical safety systems, information is gathered via local sensors. If a critical state is detected, existing actuators are respectively triggered. Vehicle-to-Vehicle or Vehicle-to-Infrastructure (Vehicle-to-X, V2X) Communication allows breaking these limitations, since vehicles are able to exchange internal information with other vehicles wirelessly. The single vehicle is then able to communicate with its environment beyond the line of sight. This results in an earlier detection of critical traffic situations, increased traffic safety and an optimized traffic flow. While currently major efforts regarding V2XC are taken to standardize protocols and communication, integration of V2XC into the overall electric/electronic (E/E) architecture of a vehicle, let alone integration aspects of combining V2X technology with established vehicular safety systems has not been looked at in detail. Using V2XC for safety critical applications demands for strict adherence to real time constraints in the overall processing chain, which starts at the sensor in the transmitting vehicle and ends up in actuators of the receiving vehicles. In between a lot of necessary processing steps make meeting latency limits a major challenge. Looking especially at security checking, data processing and data aggregation we implemented an FPGA-based approach for a V2XC system that is able to fulfil the upcoming computational demands. The system is tightly coupled to the automotive E/E architecture by extending a central car gateway. Within this work we present our approach of combining V2X technology with Adaptive Cruise Control (ACC) while utilizing the aforementioned V2X system as starting point. The paper is meant to provide a basis for future realization of V2X-based safety systems and their tight integration into E/E architectures. Therefore, we explain most important aspects concerning combination of our centralized V2X approach together with ACC capabilities within a real prototype car. This includes a declaration of the underlying concepts as well as a discussion of design decisions that were made to interface ACC and V2X with respect to performance, security and safety requirements.