Building a Robust Scenario Library for Safety Assurance of Automated Driving Systems: A Review

Ensuring the safety of Automated Driving Systems (ADSs) is both a critical and complex endeavor. The increasing demand for autonomous driving technologies underscores the importance of robust safety assurance, yet the intricate nature of these systems presents significant challenges. Scenario-based testing has emerged as a promising approach for ADS safety assurance, but the industry still lacks a comprehensive workflow to effectively implement this process. A pivotal element of scenario-based safety assurance is the creation of a scenario library that thoroughly encompasses the necessary conditions to test ADSs for deployment in specific regions. This paper offers an in-depth analysis of best practices and research in scenario-based safety assurance, aiming to develop a detailed scenario library tailored for testing ADSs within diverse driving conditions. The research addresses the need for scenario creation for the verification and validation (V&V) of ADSs across different environments. The diverse environmental conditions and road traffic behaviors present unique challenges that distinguish one region from another. While every region has its specificities, certain contexts pose particular difficulties in scenario development. This paper outlines the literature review methodology used and presents the current state of scenarios and scenario generation activities. The review synthesizes information from over a hundred sources, including research articles, standards, and best practices. The literature is evaluated across six key areas: Operational Design Domain (ODD), scenario description and representation, data sources and scenario generation methods, scenario selection, scenario assessment and test criteria, and general frameworks for ADS safety assurance. Key contributions, among others, include a structured classification of scenario generation and selection methods, identification of gaps in current practices, and a set of actionable recommendations for future research and regulatory alignment. The paper concludes with recommendations for future work, focusing on the use of scenarios for ADS V&V and proposing a scenario-generation framework tailored to various driving environments.