Abstract:The development of assessment methods for the performance of Automated Vehicles (AVs) is essential to enable and speed up the deployment of automated driving technologies, due to the complex operational domain of AVs. As traditional methods for assessing vehicles are not applicable for AVs, other approaches have been proposed. Among these, real-world scenario-based assessment is widely supported by many players in the automotive field. In this approach, test cases are derived from real-world scenarios that are obtained from driving data. To minimize any ambiguity regarding these test cases and scenarios, a clear definition of the notion of scenario is required. In this paper, we propose a more concrete definition of scenario, compared to what is known to the authors from the literature. This is achieved by proposing an ontology in which the quantitative building blocks of a scenario are defined. An example illustrates that the presented ontology is applicable for scenario-based assessment of AVs.