Hans Vangheluwe

University of Antwerp / Flanders Make · Computer Science

One of the biggest achievements of the past half century has been making ever tinier structures. This miniaturization is at the foundation of three pillars that comprise the Digital Age: (1) computation, (2) digitization, and (3) communication. First, it is discussed how developments along these three pillars have affected the field of engineered s...

Live modeling is the ability to edit an executable model at run-time, and to subsequently continue the execution instead of having to restart it. Few modeling frameworks support this feature. Much of the research concerning live modeling attempts to bring “liveness” to existing modeling languages and environments, which is a complex, and often ad h...

This document is a result of the COOCK project "Smart Port 2025: improving and accelerating the operational efficiency of a harbour eco-system through the application of intelligent technologies". The project is mainly aimed at SMEs, but also at large corporations. Together, they form the value-chain of the harbour. The digital maturity of these ac...

Message from the Chairs, The 5th Summer School on Cyber-Physical Systems and Internet of Things (SS-CPS&IoT’2024) is the fifth school in a series, organized in Budva, Montenegrin andMediterranean pearl.We were pleased to continue the tradition of hosting the SS-CPS&IoT’2024 in a hybrid format, accommodating both online and in-person participation.S...

The development of artificial intelligence models for data driven decision making has a lot of potential for the manufacturing sector. Nevertheless, applications in industry are currently limited to the actionable insights one can discover from the available data and knowledge of a manufacturing system. We call the process to obtain such insights “...

Model-based systems engineering (MBSE) focuses on using models to support the design, optimization, simulation, and ultimately deployment of complex cyber-physical systems (CPSs). These models enable reasoning about and predicting the behavior of the (realized) real-world system in silico. The value of using such (predictive) model depends on its v...

The pace of reporting on Digital Twin (DT) projects continues to accelerate both in industry and academia. However, these experience reports often leave out essential characteristics of the DT, such as the scope of the system-under-study, the insights and actions enabled, and the time-scale of processing. A lack of these details could therefore ham...

Digital Models/Shadows/Twins/...have been given numerous definitions and descriptions in the literature. There is no consensus on terminology, nor a comprehensive description of workflows nor architectures. In this paper, we use the catch-all “Digital T” (pronounced “Digital Twinning”) to refer to all concepts, techniques, architectures, ...related...

Inconsistencies between stakeholders' views pose a severe challenge in the engineering of complex systems. The past decades have seen a vast number of sophisticated inconsistency management techniques being developed. These techniques build on the common idea of "managing consistency instead of removing inconsistency", as put forward by Finkelstein...

The pace of reporting on Digital Twin (DT) projects continues to accelerate both in industry and academia. However, these experience reports often leave out essential characteristics of the DT, such as the scope of the system-under-study, the insights and actions enabled, and the time-scale of processing. A lack of these details could therefore ham...

The Internet of Things and its technologies have evolved quickly in recent years. It became an umbrella term for various technologies, embedded devices, smart objects, and web services. Although it has gained maturity, there is still no clear or common definition of references for creating WSN-based IoT systems. In the awareness that creating an om...

Organisations are intensely developing Digital Twins (DTs) to correctly and efficiently answer questions about the history and behaviour of physical systems. However, it is not clear how to construct these DTs starting from the data, information, knowledge, and wisdom available in the organisation. In this work, we present our approach to DT constr...

Current automotive standards such as ISO 26262 require Hazard Analysis and Risk Assessment (HARA) on possible hazards and consequences of safety-critical components. This work attempts to ease this labour-intensive process by using machine learning-based fault injection to discover representative hazardous situations. Using a Simulation-Aided Hazar...

Digital Twins (DTs) (including Digital Shadows) are simulation models running in parallel with a real-world system while being fed the same input stimuli as that system. They can be used to analyze, optimize and adapt complicated engineered systems. This paper proposes a generic workflow to construct a Digital Shadow of a simple line-following robo...

This chapter gives an introduction to the key concepts and terminology relevant for model-based analysis tools and their composition. In the first half of the chapter, we introduce concepts relevant for modelling and composition of models and modelling languages. The second half of the chapter then focuses on concepts relevant to analysis and analy...

This chapter targets a better understanding of the compositionality of analyses, including different forms of compositionality and specific conditions of composition. Analysis involves models, contexts, and properties. These are all expressed in languages with their own semantics. For a successful composition of analyses, it is therefore important...

The complexity of cyber–physical systems ( CPSs ) is commonly addressed through complex workflows , involving models in a plethora of different formalisms , each with their own methods, techniques, and tools. Some workflow patterns , combined with particular types of formalisms and operations on models in these formalisms, are used successfully in...

Developing new competitive approaches to the physical and virtual world integration with cyber-physical systems (CPS) is one of the European Union research priorities. CPS change the way people interface with systems, similarly to the way in which the Internet has transformed the way people interface with information. The two-hemisphere model-drive...

Digital twins (DTs) are prevalent throughout industrial domains as evidenced by the rapid pace of experience reports in the literature. However, there remains disagreement about the precise definition of a DT and the essential characteristics in the DT paradigm, such as the scope of the system-under-study and the time-scale of its communication wit...

This chapter discusses the design and development of a Cyber-physical System (CPS) use case. The system is developed using the Internet of Things (IoT) components and Wireless Sensor Network (WSN) elements. The proposed system is composed of different hardware parts, software elements, computing components and communication technologies resulting i...

Discrete-event modelling and simulation languages can be classified based on their world view: event scheduling, activity scanning, or process interaction. To study the semantics of these languages one may investigate the relationship between them, and in particular translate models between languages in different world views. A translation approach...

There are various computation components, operating systems , and firmware used in the development of the Internet of Things (IoT). This variety increases the structural complexity and development cost and effort of the IoT systems. Besides, analyzing and troubleshooting these systems are time-consuming, costly, and cumbersome. To address these pro...

The variety of smart devices and their communication models increase the development complexity of embedded software for IoT. Thus, the development of these systems becomes more error-prone, complex, and costly. To tackle this problem, in this study, a model-driven approach is proposed for the development of RIOT-OS based IoT systems. To this end,...

Model-Based Systems Engineering (MBSE) provides workflows, methods, techniques and tools for optimal simulation-based design and realization of complex Software-Intensive, Cyber-Physical Systems. One of the key benefits of this approach is that the behavior of the realized system can be reasoned about and predicted in-silico, before any prototype h...

In this paper, we analyse the impact of delayed event detection on the stability of a 2-mode planar hybrid automata. We consider hybrid automata with a unique equilibrium point for all the modes, and we find the maximum delay that preserves stability of that equilibrium point. We also show for the class of hybrid automata treated that the instabili...

Correct co-simulation results require a careful consideration of how the interacting simulators are implemented. In version 2.0 of the FMI Standard, input handling implementation is left implicit, which leads to the situation where a simulator can be interacted with in a manner that its implementation does not expect, yielding incorrect results. In...

Co-simulation is a powerful technique for performing full-system simulation. Multiple black-box models and their simulators are combined together to provide the behaviour for a full system. However, the black-box nature of co-simulation and potentially infinite configuration space means that configuration of co-simulations is a challenging problem...

The description of a complex system in terms of constituent components and their interaction is one of the most natural and intuitive ways of decomposition. Causal Block Diagram (CBD) models combine subsystem blocks in a network of relationships between input signals and output signals. Popular modelling and simulation tools such as Matlab/Simulink...

Statecharts, introduced by David Harel in 1987, is a formalism used to specify the behaviour of timed, autonomous, and reactive systems using a discrete-event abstraction. It extends Timed Finite State Automata with depth, orthogonality, broadcast communication, and history. Its visual representation is based on higraphs, which combine graphs and E...

Modeling and analysis of Cyber-Physical Systems (CPS) is an inherently multi-disciplinary endeavour. Anyone starting in this field will unavoidably face the need for a literature reference that delivers solid foundations. Although, in specific disciplines, many techniques are used already as a matter of standard practice, their fundamentals and app...

DEVS is a popular formalism for modelling complex dynamic systems using a discrete-event abstraction. At this abstraction level, a timed sequence of pertinent “events” input to a system (or internal, in the case of timeouts) cause instantaneous changes to the state of the system. Between events, the state does not change, resulting in a piecewise c...

Model-based System Engineering (MBSE) is a methodology that uses models throughout the engineering to replace the paper-based approach of communication among stakeholders. Multi-Paradigm Modelling (MPM) is at the core of this engineering approach as for each phase in the engineering process the most appropriate models at the most appropriate levels...

Model transformations are essential elements of model-driven engineering (MDE) solutions, as they enable the automatic manipulation of models. MDE promotes the creation of domain-specific metamodels, but without proper reuse mechanisms, model transformations need to be developed from scratch for each new metamodel. In this paper, our goal is to und...

The widespread adoption of Modelling and Simulation (M8S) techniques hinges on the availability of tools supporting each phase in the M8S-based workflow. This includes tasks such as specifying, implementing, experimenting with, as well as debugging, simulation models. We have previously developed a technique where advanced debugging environments ar...

This open access book coherently gathers well-founded information on the fundamentals of and formalisms for modelling cyber-physical systems (CPS). Highlighting the cross-disciplinary nature of CPS modelling, it also serves as a bridge for anyone entering CPS from related areas of computer science or engineering. Truly complex, engineered systems—k...

Smart Cyber-Physical Systems (sCPS) are a novel kind of Cyber- Physical System engineered to take advantage of large-scale cooperation between devices, users and environment to achieve added value in the face of uncertainty and changing environments. Examples of sCPS include modern traffic systems, Industry 4.0 systems, systems for smart buildings,...

To develop complex systems and tackle their inherent complexity, (executable) modelling takes a prominent role in the development cycle. But whereas good tool support exists for programming, tools for executable modelling have not yet reached the same level of functionality and maturity. In particular, live programming is seeing increasing support...

The design of safety-related systems traditionally has long and costly development cycles due to the highly manual safety engineering process, which is guided by industry standards. In this paper, we present a modelling framework that supports DevOps principles of continuous testing and fast development iterations for the design of safety-critical...

This paper presents our contract-based design technique for formalizing requirements during the design phase of a complicated and safety-critical automotive component. In our approach, contracts are created using property specification patterns to eliminate ambiguous unstructured natural language requirements, which could lead to misinterpretations...

Computational notebooks are gaining widespread acceptance as a paradigm for storage, dissemination, and reproduction of experimental results. In this paper, we define the computational notebook paradigm (CNP) consisting of entities and processes and discuss how the reproducibility of the experimental process and results is enhanced by each element....

Models are well-defined abstractions that provide cost-effective representations of the real-world for a precise purpose. When dealing with complex problems, there usually exist multiple abstractions, typically describing partially overlapping details of the system under study, and resulting in a hierarchy of abstractions. Adaptive abstraction leve...

Simulation-based analyses of Cyber-Physical Systems are fundamental in industrial design and testing approaches. The utility of analyses relies on the correct configuration of the simulation tools, which can be highly complicated. System engineers can normally judge the results, and either evaluate multiple simulation algorithms, or change the mode...

The huge variety of smart devices and their communication models increases the development complexity of embedded software for the Internet of Things. As a consequence, development of these systems becomes more complex, error-prone, and costly. To tackle this problem, in this study, a model-driven approach is proposed for the development of Contiki...

We propose an algorithm to restrict the switching signals of a constrained switched system in order to guarantee its stability, while at the same time attempting to keep the largest possible set of allowed switching signals. Our work is motivated by co-simulation of complex dynamical systems by multiple cores. There, numerical stability is a hard...