Connected and autonomous vehicle (CAV)
Road vehicles are becoming increasingly automated. Sensors and Advanced Driver Assistance Systems (ADAS) are common equipment of modern cars, while Connected and Automated Vehicles (CAV) are currently actively developed by automobile companies and suppliers, research centers, universities, and standardisation organizations. One of the main arguments for the driving automation lies in safety aspects. Indeed, most accidents are due to human errors that could be avoided with safe automated systems.
Functional architecture of automated vehicles
> The perception phase, when the system measures the surrounding thanks to sensors and cameras and interpret the driving situation.
> The motion planning phase, when the system determines for the driving situation a safe and performant reference trajectory to follow.
> The actuation phase for the control of the vehicle to the reference trajectory.
Functional safety analysis
Quantitative functional safety analysis of the automatized systems is necessary to evaluate and demonstrate their reliability and safety. However, automated driving is dynamic process having a complex functional architecture, and the driving situations are various. Classical static approaches (see the ISO-26262 international norm for functional safety of road vehicles) consist of exhaustive analysis with corresponding risk evaluation for all driving situations and vehicle items. Such a task is not realisable for automated driving, especially for urban traffic and at levels 3, 4 or 5 of automation without supervision. Indeed, the system and no more the driver is responsible in case of hazard at these automation levels. There is currently an important development of specific tools and methods for the safety of automated vehicles able to take into account the varied dynamical aspects of the driving (see also ISO/PAS 21448:2019 Standard for the safety of the intended functionality of road vehicles).