A key milestone has been reached in the CITRUS project (C-ITS for Vulnerable Road Users) within Work Package 2 (WP2) – Specification of Use Cases and Requirements. The project’s objective is to develop a cooperative system that uses C-ITS technologies to calculate the probability of collisions between different road users—depending on the use case—and provide early warnings when an elevated risk is detected.
Between the beginning of the year and mid-April 2026, extensive consultations were held with project partners and external stakeholders to establish a solid foundation for the preparation of the requirements specification. Particular emphasis was placed on collaboration with the Letter of Intent (LOI) partners, including Wiener Linien and the Vienna Mobility Agency (MOBAG).
These discussions specifically considered the perspectives of different user groups. In addition to pedestrians and cyclists, particular attention was given to especially vulnerable road users, including people with reduced mobility and individuals with visual impairments. This differentiated approach supports the development of realistic use cases and requirements.
In parallel, technical coordination activities were carried out with Yunex Traffic. Furthermore, discussions with AustriaTech addressed open questions regarding the use of the C-ITS Broker, with the aim of gaining a better understanding of its functionality and evaluating the extent to which it could become part of the overall system.
The outcomes of these activities led to the successful finalization of the requirements specification, which is scheduled to be reviewed, aligned, and approved during a consortium meeting in April 2026.
Building on the results developed in WP2, the use case descriptions have now been completed, while the evaluation design is currently being prepared. At the same time, WP3 has commenced, focusing on the specification of the system design and thereby laying the foundation for the technical implementation.