Challenges for MBSE and PLE for Legacy Product-Based System Environments

Model-Based System Engineering (MBSE) and Product Line Engineering (PLE) are well-known approaches in industry for the management and design of the architecture of complex systems. The railway signalling business has some specific characteristics that need to be considered in system engineering: railway signalling systems have a long life time and new systems have to integrate interfaces to many types of legacy railway safety products. This situation has led to different technical system approaches: railway infrastructure companies as customers prefer either turn-key projects fulfilled by one supplier or tend to define individual subsystems that can be integrated to a complete system. This article shows how Thales masters both approaches by using the method ARCADIA and the open source modelling tool Capella in the specific case of pre-existing subsystems and how the resulting variability is handled. An outlook will be given to extensions that allow an early safety analysis of models and will provide support for automatic test design.