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Abstract-Cyberphysical systems, with their interdependence between physical behaviour and digital control, need insights from frequency domain control engineering, state space control engineering and discrete formal systems theory for their proper description. Neglecting any of these, results in descriptions that omit essential details. Hybrid Event-B is a formalism that enables all the relevant detail to be assimilated. A case study based on yaw control for the KURT e-vehicle is used as a testbed to explore the effective interaction between the various needed disciplines in exploring a specific design issue, the formalisation of yaw control discretization, using Hybrid Event-B.

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-This paper describes the theoretical principles and the practical implementation of OpenCookbook, an environment for systems engineering. The environment guides and supports developers during requirements and specification capturing over architectural modelling and workplan development till validation and final release. It features a coherent and unified system engineering methodology based on the interacting entities paradigm. In order to implement it, a generic web portal was developed. Targeting embedded systems, it nevertheless was proven to be an effective tool for a wide range of other system domains. OpenCookbook can be tailored to the needs of a specific organisation as well as accommodate engineering standards like IEC61508.

VirtuosoNext TM is a distributed real-time operating system (RTOS) featuring a generic programming model dubbed Interacting Entities. This paper focuses on these interactions, implemented as so-called Hubs. Hubs act as synchronisation and communication mechanisms between the application tasks and implement the services provided by the kernel as a kind of Guarded Protected Action with a well defined semantics. While the kernel provides the most basic services, each carefully designed, tested and optimised, tasks are limited to this handful of basic hubs, leaving the development of more complex synchronization and communication mechanisms up to application specific implementations. In this work we investigate how to support a programming paradigm to compositionally build new services, using notions borrowed from the Reo coordination language, and relieving tasks from coordination aspects while delegating them to the hubs. We formalise the semantics of hubs using an automata model, identify the behaviour of existing hubs, and propose an approach to build new hubs by composing simpler ones. We also provide tools and methods to analyse and simplify hubs under our automata interpretation. In a first experiment several hub interactions are combined into a single more complex hub, which raises the level of abstraction and contributes to a higher productivity for the programmer. Finally, we investigate the impact on the performance by comparing different implementations on an embedded board.

Systems engineering has emerged because of the growing complexity of systems and the growing need for systems to provide a reliable service. The latter has to be defined in a wider context of trustworthiness and covering aspects like safety, security, human-machine interface design and even privacy. What the user expects is an acceptable quality of service (QoS), a property that is difficult to measure as it is a qualitative one. In this paper, we present a novel criterion, called assured reliability and resilience level (ARRL) that defines QoS in a normative way, largely by taking into account how the system deals with faults. ARRL defines 7 levels of which the highest one can be described as the level where the system becomes antifragile.