Event-Chain Analysis for Automated Driving and ADAS Systems: Ensuring Safety and Meeting Regulatory Timing Requirements
Sebastian Dingler, Philip Rehkop, Florian Mayer, Ralf Muenzenberger
TL;DR
The paper tackles the challenge of meeting stringent regulatory timing requirements for ADS/ADAS by introducing a White-Box Event-Chain Analysis (ECA) that links regulatory text to architecture and enables end-to-end timing verification from perception to actuation. It defines Event-Chains as sequences of causally related, discrete events and develops an ontology to derive formal timing requirements from regulations, allowing both Black-Box and White-Box views with budgets across subsystems. A detailed Automated Emergency Braking (AEB) case study demonstrates how probabilistic sensor models and braking dynamics can be embedded in executable Event-Chain models, with simulation-based verification using Monte Carlo runs to assess compliance and drive optimization of sensing and timing budgets. The approach yields auditable homologation evidence, supports shift-left verification, and offers practical guidance for OEMs in balancing regulatory compliance with system feasibility, as shown in industrial practice within Daimler Truck environments. Mathematical formulations for stopping distance, time-to-react, and budgeting (e.g., $t_{ ext{acq}}\, ext{and}\,t_{ ext{det}}\, ext{constraints}$, $TTR(d_o,v_{ ext{ego}})$) underpin the methodology and enable quantitative regulatory assurance through chronSIM simulations and probabilistic analysis.
Abstract
Automated Driving Systems (ADS), including Advanced Driver Assistance Systems (ADAS), must fulfill not only high functional expectations but also stringent timing constraints mandated by international regulations and standards. Regulatory frameworks such as UN regulations, NCAP standards, ISO norms, and NHTSA guidelines impose strict bounds on system reaction times to ensure safe vehicle operation. This paper presents a structured, White-Box methodology based on Event-Chain Modeling to address these timing challenges. Unlike Black-Box approaches, Event-Chain Analysis offers transparent insights into the timing behavior of each functional component - from perception and planning to actuation and human interaction. This perspective is also aligned with multiple regulations, which require that homologation dossiers provide evidence that the chosen system architecture is suitable to ensure compliance with the specified requirements. Our methodology enables the derivation, modeling, and validation of end-to-end timing constraints at the architectural level and facilitates early verification through simulation. Through a detailed case study, we demonstrate how this Event-Chain-centric approach enhances regulatory compliance, optimizes system design, and supports model-based safety analysis techniques, with results showing early identification of compliance issues, systematic parameter optimization, and quantitative evidence generation through probabilistic analysis.
