PhD defense of Meriem SMATI

Mrs Meriem SMATI defends her PhD September 10th 2026 at 2PM, entitled: "Definition and Development of a Digital Twin Framework for Dynamic Systems of Systems". The defense takes place on Doua campus.

Summary: Digital Twins represent a promising approach to monitoring, analyzing, and managing complex systems. However, existing approaches primarily focus on individual systems and provide limited support for coordinating and managing a System of Systems (SoS) as a whole. Addressing this limitation requires ensuring coherence, adaptability, interoperability, and scalability across the constituent Digital Twins while considering their interdependencies and evolution.

This work defines and develops a Digital Twin framework aimed at enhancing the resilience of Systems of Systems. It investigates how a System-of-Systems Digital Twin can be designed and engineered to support global supervision, coordination, and decision-making. Two systematic literature reviews were conducted to identify the limitations of existing approaches and clarify the role of Digital Twins in improving the resilience of Systems of Systems. Based on these findings, a layered architecture is proposed and subsequently extended with an orchestration layer responsible for coordinating the constituent Digital Twins, maintaining their semantic alignment, facilitating their interoperability, and ensuring consistency between local decisions and the global objectives of the System of Systems.

A generation-assisted engineering approach called DTGen is also introduced to facilitate the creation of Digital Twin engineering artifacts from explicit specifications. It supports the validation and normalization of specifications, the generation of executable artifacts, and their organization within a System-of-Systems context. The proposed contributions are evaluated through several use cases, including anomaly detection using a Cognitive Super Digital Twin, swarm coordination through TwinHive, and resilient smart waste collection using WasteTwin.

The results demonstrate that a System-of-Systems Digital Twin cannot be reduced to a simple aggregation of individual Digital Twins. It requires additional reasoning, coordination, and management capabilities to address interdependencies, disturbances, system evolution, and global objectives. This work therefore contributes to the development of more coherent, interoperable, scalable, adaptable, and resilient System-of-Systems Digital Twins.

Keywords: Digital Twin, System of Systems, Model-Driven Engineering, System of Digital Twins, Orchestration, Interoperability, Resilience.

Thesis Committee

• Sophie Ebersold, Professor, Toulouse Jean Jaurès University, Reviewer
• Yasmina Maïzi, Full Professor, Université du Québec à Montréal (UQAM), Reviewer
• Benoît Combemale, Professor, University of Rennes, Examiner
• Robert Pellerin, Full Professor, Polytechnique Montréal, Examiner
• Bentley Oakes, Associate Professor, Polytechnique Montréal, Examiner
• Vincent Cheutet, Professor, INSA Lyon, Thesis Director
• Christophe Danjou, Associate Professor, Polytechnique Montréal, Thesis Director
• Jannik Laval, Associate Professor, HDR, Lumière Lyon 2 University, Thesis Co-Director