Functional requirements for automated bus transit systems based on human driver tasks

Driven by advancements in automation and connectivity, this paper explores the development of automated Public Transportation (PT) systems. This study addresses the critical role of human bus drivers in ensuring safety, accessibility, and service quality, examining how their diverse responsibilities can be translated into a modular technical framework. By analyzing legal frameworks in Europe and North America and conducting expert interviews with bus drivers in Munich, Germany, we identify the main tasks human drivers perform, including passenger safety monitoring, passenger assistance, communication, vehicle control, traffic monitoring, and service operation. From these tasks, we derive a conceptual framework of functional requirements organized within a Sense-Plan-Act (SPA) model and a Service-Oriented Architecture (SOA). We propose a Public Transport Control System that integrates requirements into a high-level architecture, providing a foundation for developing systems that can operate safely and efficiently while maintaining high service quality and meeting legal standards.