EN FR
EN FR
I4S - 2025

2025Activity report​Project-TeamI4S

RNSR: 200920933U​‌
  • Research center Inria Centre​​ at Rennes University
  • In​​​‌ partnership with:Université Gustave​ Eiffel
  • Team name: Inference​‌ for Intelligent Instrumented InfraStructures​​
  • In collaboration with:Département​​​‌ Composants et systèmes

Creation​ of the Project-Team: 2024​‌ November 01

Each year,​​ Inria research teams publish​​​‌ an Activity Report presenting​ their work and results​‌ over the reporting period.​​ These reports follow a​​​‌ common structure, with some​ optional sections depending on​‌ the specific team. They​​ typically begin by outlining​​​‌ the overall objectives and​ research programme, including the​‌ main research themes, goals,​​ and methodological approaches. They​​​‌ also describe the application​ domains targeted by the​‌ team, highlighting the scientific​​ or societal contexts in​​​‌ which their work is​ situated.

The reports then​‌ present the highlights of​​ the year, covering major​​​‌ scientific achievements, software developments,​ or teaching contributions. When​‌ relevant, they include sections​​ on software, platforms, and​​​‌ open data, detailing the​ tools developed and how​‌ they are shared. A​​ substantial part is dedicated​​​‌ to new results, where​ scientific contributions are described​‌ in detail, often with​​ subsections specifying participants and​​​‌ associated keywords.

Finally, the​ Activity Report addresses funding,​‌ contracts, partnerships, and collaborations​​ at various levels, from​​​‌ industrial agreements to international​ cooperations. It also covers​‌ dissemination and teaching activities,​​ such as participation in​​ scientific events, outreach, and​​​‌ supervision. The document concludes‌ with a presentation of‌​‌ scientific production, including major​​ publications and those produced​​​‌ during the year.

Keywords‌

Computer Science and Digital‌​‌ Science

  • A5.9.2. Estimation, modeling​​
  • A5.9.6. Optimization tools
  • A6.1.2.​​​‌ Stochastic Modeling
  • A6.1.4. Multiscale‌ modeling
  • A6.1.5. Multiphysics modeling‌​‌
  • A6.2.1. Numerical analysis of​​ PDE and ODE
  • A6.2.4.​​​‌ Statistical methods
  • A6.2.5. Numerical‌ Linear Algebra
  • A6.2.6. Optimization‌​‌
  • A6.2.8. Computational geometry and​​ meshes
  • A6.3. Computation-data interaction​​​‌
  • A6.3.1. Inverse problems
  • A6.3.2.‌ Data assimilation
  • A6.3.3. Data‌​‌ processing
  • A6.3.4. Model reduction​​
  • A6.3.5. Uncertainty Quantification
  • A6.4.3.​​​‌ Observability and Controlability
  • A6.5.1.‌ Solid mechanics
  • A6.5.2. Fluid‌​‌ mechanics
  • A6.5.3. Transport
  • A6.5.4.​​ Waves
  • A9.2. Machine learning​​​‌
  • A9.2.1. Supervised learning

Other‌ Research Topics and Application‌​‌ Domains

  • B3.1. Sustainable development​​
  • B3.2. Climate and meteorology​​​‌
  • B3.3.1. Earth and subsoil‌
  • B4.3.2. Hydro-energy
  • B4.3.3. Wind‌​‌ energy
  • B5.1. Factory of​​ the future
  • B5.2. Design​​​‌ and manufacturing
  • B5.2.1. Road‌ vehicles
  • B5.2.2. Railway
  • B5.2.3.‌​‌ Aviation
  • B5.2.4. Aerospace
  • B5.5.​​ Materials
  • B5.9. Industrial maintenance​​​‌
  • B6.5. Information systems
  • B6.6.‌ Embedded systems
  • B7.2.2. Smart‌​‌ road
  • B8.1. Smart building/home​​
  • B8.1.1. Energy for smart​​​‌ buildings
  • B8.1.2. Sensor networks‌ for smart buildings
  • B8.2.‌​‌ Connected city
  • B9.5.3. Physics​​
  • B9.5.5. Mechanics

1 Team​​​‌ members, visitors, external collaborators‌

Research Scientists

  • Michael Doehler‌​‌ [Team leader,​​ INRIA, Researcher,​​​‌ HDR]
  • Vincent Baltazart‌ [UNIV GUSTAVE EIFFEL‌​‌, Researcher]
  • Xavier​​ Chapeleau [UNIV GUSTAVE​​​‌ EIFFEL, Researcher]‌
  • Christophe Droz [INRIA‌​‌, ISFP, HDR​​]
  • Jean Dumoulin [​​​‌UNIV GUSTAVE EIFFEL,‌ Researcher]
  • Vincent Le‌​‌ Cam [UNIV GUSTAVE​​ EIFFEL, Senior Researcher​​​‌]
  • Julien Le Scornec‌ [UNIV GUSTAVE EIFFEL‌​‌, Researcher, from​​ Dec 2025]
  • Adrien​​​‌ Melot [INRIA,‌ Starting Research Position]‌​‌
  • Laurent Mevel [INRIA​​, Senior Researcher,​​​‌ HDR]
  • Romain Noel‌ [UNIV GUSTAVE EIFFEL‌​‌, Researcher]
  • Qinghua​​ Zhang [INRIA,​​​‌ Senior Researcher, HDR‌]

Post-Doctoral Fellows

  • Neha‌​‌ Aswal [INRIA,​​ Post-Doctoral Fellow, until​​​‌ Nov 2025]
  • Julian‌ Legendre [INRIA,‌​‌ Post-Doctoral Fellow, until​​ Aug 2025]
  • Nicolas​​​‌ Madinier [INRIA,‌ Post-Doctoral Fellow, from‌​‌ Sep 2025]
  • Boualem​​ Merainani [UNIV GUSTAVE​​​‌ EIFFEL]

PhD Students‌

  • Clement Bardet [INRIA‌​‌]
  • Antoine Barré [​​UNIV GUSTAVE EIFFEL,​​​‌ from Nov 2025]‌
  • Hovanes Boksyan [INRIA‌​‌, from Oct 2025​​]
  • Nina Delette [​​​‌IFPEN, CIFRE]‌
  • Arij Fawaz [UNIV‌​‌ GUSTAVE EIFFEL]
  • Alvaro​​ Gavilan Rojas [INRIA​​​‌]
  • Mira Kabbara [‌UNIV GUSTAVE EIFFEL]‌​‌
  • Marios Kaminiotis [UNIV​​ GUSTAVE EIFFEL]
  • Pierre​​​‌ Lague [INRIA,‌ from Oct 2025]‌​‌
  • Zakariae Moutaouakil [INRIA​​]
  • Hamado Ouedraogo [​​​‌UNIV GUSTAVE EIFFEL,‌ from Oct 2025]‌​‌
  • Louis Ramseyer [INRIA​​, from Nov 2025​​​‌]
  • Clement Rigal [‌UNIV GUSTAVE EIFFEL,‌​‌ until Jul 2025]​​
  • Lucas Rouhi [INRIA​​​‌]
  • Benoit Senard [‌INRIA]

Technical Staff‌​‌

  • Arthur Bouché [UNIV​​ GUSTAVE EIFFEL, Engineer​​​‌]
  • Jean-Noel Coueron [‌UNIV GUSTAVE EIFFEL,‌​‌ Engineer, from Feb​​​‌ 2025]
  • Nathanaël Gey​ [UNIV GUSTAVE EIFFEL​‌, Engineer]
  • Mathias​​ Malandain [INRIA,​​​‌ Engineer]
  • Thibaud Toullier​ [UNIV GUSTAVE EIFFEL​‌, Engineer]
  • Adji​​ Touré [UNIV GUSTAVE​​​‌ EIFFEL, Engineer,​ from Oct 2025]​‌

Interns and Apprentices

  • Methmika​​ Chamath Jayawardene Athulkotte Mahawasala​​​‌ Muhandiramge [INRIA,​ Intern, from May​‌ 2025 until Oct 2025​​]
  • Hovanes Boksyan [​​​‌INRIA, Intern,​ from Feb 2025 until​‌ Jul 2025]
  • Mathis​​ Creff [UNIV RENNES​​​‌, Intern, from​ May 2025 until Jul​‌ 2025]
  • Lucas Czamanski​​ Meireles [UNIV GUSTAVE​​​‌ EIFFEL, Intern,​ from Apr 2025 until​‌ Oct 2025]
  • Nino​​ Dos Santos [UNIV​​​‌ GUSTAVE EIFFEL, Intern​, from Apr 2025​‌ until Jun 2025]​​
  • Lucas Doula [UNIV​​​‌ GUSTAVE EIFFEL, Intern​, from Apr 2025​‌ until Oct 2025]​​
  • Arthur Kittler [INRIA​​​‌, Intern, from​ Feb 2025 until Aug​‌ 2025]
  • Nino Landormy​​ [UNIV GUSTAVE EIFFEL​​​‌, Apprentice]
  • Valentine​ Nayl [INRIA,​‌ Intern, from May​​ 2025 until Jul 2025​​​‌]
  • Hamza Saissi [​UNIV GUSTAVE EIFFEL,​‌ Intern, from May​​ 2025 until Sep 2025​​​‌]
  • Coralie Thuiller [​ENS RENNES, Intern​‌, from Sep 2025​​]
  • Adji Touré [​​​‌UNIV GUSTAVE EIFFEL,​ Apprentice, until Aug​‌ 2025]

Administrative Assistants​​

  • Yveline Gourbil [UNIV​​​‌ GUSTAVE EIFFEL]
  • Gunther​ Tessier [INRIA]​‌

Visiting Scientists

  • Nikhil Mahar​​ [IIT Mandi, India​​​‌, from May 2025​ until Jun 2025]​‌
  • Shereena Oa [IIT​​ Mandi, India, from​​​‌ May 2025 until Jun​ 2025]
  • Lisa Marie​‌ Schwegmann [University of​​ Rostock, from Aug​​​‌ 2025 until Oct 2025​]
  • Martina Vitali [​‌ECOLE POLYT. MILAN,​​ from Mar 2025 until​​​‌ Aug 2025]

External​ Collaborator

  • Boris Lossouarn [​‌CNAM, from Sep​​ 2025, Associate Professor​​​‌ Delegation]

2 Overall​ objectives

2.1 Context

The​‌ design, monitoring and maintenance​​ of engineering structures subject​​​‌ to noise and other​ environmental perturbations are important​‌ aspects of research. The​​ goal is to ensure​​​‌ efficient operation, safety, durability​ and sustainability, while the​‌ structures are aging under​​ increased loads and environmental​​​‌ burdens, or even passing​ their design life. This​‌ concerns, to name a​​ few examples, classic civil​​​‌ structures like bridges or​ buildings, more recent structures​‌ like wind turbines, or​​ new designs based, e.g.,​​​‌ on meta-materials. For such​ structures, Structural Health Monitoring​‌ (SHM) has the goal​​ to continuously assess their​​​‌ state – and in​ particular the appearance of​‌ faults/damages or any other​​ abnormal behavior – based​​​‌ on dynamic response measurements​ from an array of​‌ sensors. In particular, an​​ automated and online structural​​​‌ assessment allows optimized maintenance,​ avoids critical failure, increases​‌ safety and extends the​​ lifetime of structures.

Strongly​​​‌ connected to the data-based​ evaluation of structures is​‌ structural analysis and design,​​ with the purpose to​​​‌ understand, to predict and​ to optimize structural behavior,​‌ to infer structural changes​​ based on monitoring data,​​ and to efficiently monitor​​​‌ new designs. The monitoring‌ technology itself has evolved‌​‌ rapidly in the last​​ decade and has become​​​‌ affordable, allowing the large-scale‌ instrumentation of critical structures.‌​‌ Besides classical sensors that​​ are attached to a​​​‌ structure (e.g., accelerometers, fiber‌ optics), the technology for‌​‌ vision-based full-field measurements has​​ become available very recently​​​‌ (e.g., video-based vibration measurements,‌ infrared thermography).

Indeed, the‌​‌ rising consideration of physical​​ model information, together with​​​‌ the availability of full‌ field sensing technologies, enable‌​‌ a change of the​​ SHM paradigm for our​​​‌ team project. Previously, the‌ main focus of SHM‌​‌ was the estimation of​​ dynamic system parameters and​​​‌ the detection of changes‌ therein under environmental nuisance,‌​‌ based on measurement data​​ from sparse sensor instrumentations,​​​‌ and with the purpose‌ of statistical decision making‌​‌ to infer if there​​ is a change or​​​‌ not. Now, SHM can‌ envisage the much larger‌​‌ goal of monitoring the​​ full structural state,​​​‌ moving towards a digital‌ twin of the monitored‌​‌ structure. For such an​​ online assessment of the​​​‌ structural state, the information‌ from the measurement data‌​‌ need to be fused​​ with the physical information​​​‌ from possibly complex structural‌ models, where the ultimate‌​‌ goal is structural performance​​ analysis, prediction and optimization.​​​‌ Here, complex indicates the‌ departure from simple finite‌​‌ element modeling of linear​​ vibration behavior that is​​​‌ classically used in the‌ domain of SHM, to‌​‌ more realistic (and complex)​​ modeling of the physical​​​‌ phenomena characterizing the structural‌ behavior, involving, e.g., wave‌​‌ propagation, aerothermics, multi-physics modeling​​ including thermal behavior, non-linear​​​‌ dynamics, thermodynamics, cyber-physical systems,‌ etc.

The I4S team‌​‌ aims at addressing the​​ whole chain of SHM​​​‌ in a holistic approach,‌ including the exploitation of‌​‌ new sensor technologies, physical​​ modeling for structural analysis​​​‌ and design as well‌ as measurement data-driven analysis‌​‌ of the dynamic systems,​​ which together give rise​​​‌ to digital twinning and‌ performance prediction by fusing‌​‌ measurement data with physical​​ models. The team is​​​‌ characterized by its multidisciplinarity‌ between physical modeling, statistical‌​‌ signal processing and engineering​​ applications, where a strong​​​‌ interaction between the aforementioned‌ aspects is a key‌​‌ to the success of​​ SHM.

The I4S team​​​‌ is affiliated to Université‌ Gustave Eiffel, where it‌​‌ is part of the​​ COSYS (Components and Systems)​​​‌ department in the SII‌ (Instrumented Structures and Systems)‌​‌ laboratory. The COSYS department​​ consists of nine laboratories​​​‌ with the overall goal‌ to develop the concepts‌​‌ and tools needed to​​ improve the basic knowledge,​​​‌ methods, technologies and operational‌ systems required for the‌​‌ renewed intelligence of mobility,​​ infrastructure networks and major​​​‌ urban systems. The SII‌ laboratory is concerned with‌​‌ the development of concepts​​ and methods for instrumentation​​​‌ and structural monitoring. Besides‌ the shared research road‌​‌ map with COSYS-SII, a​​ particular benefit for I4S​​​‌ is the access to‌ experimental measurement and testing‌​‌ facilities for proofs of​​ concept and benchmarking, which​​​‌ are commonplace in civil‌ engineering labs but not‌​‌ at Inria. This allows​​ the I4S team to​​​‌ complement theoretical developments with‌ experimental validation, and facilitates‌​‌ transfer.

In this context,​​​‌ the team project contributes​ to societal challenges on​‌ green and sustainable infrastructures,​​ where smart monitoring reduces​​​‌ the energy consumption of​ infrastructure during operation, reduces​‌ downtime, and optimizes and​​ prolongs the service life​​​‌ of structures. Furthermore, the​ final goal of smart​‌ structures is low energy​​ consumption of the structure​​​‌ (during construction and operation)​ as well as durability​‌ over time, based on​​ robust designs allowing optimized​​​‌ monitoring and diagnosis.

2.2​ General objective

The general​‌ objective of the I4S​​ team is the design​​​‌ of autonomous and robust​ methods for SHM –​‌ i.e., characterization of their​​ state, the characterization of​​​‌ structural changes over time,​ and the structural performance​‌ assessment and prediction –​​ based on measurement data​​​‌ and physical models. Herein,​ robustness is a key​‌ to practical relevance and​​ addresses different aspects, such​​​‌ as noise, environmental nuisance,​ or numerical feasibility or​‌ stability of methods, e.g.,​​ when dealing with very​​​‌ complex physical models or​ new full-field measurement systems​‌ involving now thousands or​​ millions of outputs to​​​‌ be processed.

In order​ to understand the structural​‌ behavior based on measurement​​ data, structural analysis and​​​‌ design are becoming an​ important part of the​‌ research activity, with the​​ goal that SHM methods​​​‌ exploit both data and​ the related physical models​‌ in an optimal way.​​ Besides the consideration of​​​‌ classical linear structural behavior​ that reasonably approximates a​‌ wide range of structures​​ (e.g., most bridges, buildings),​​​‌ other structures show some​ intrinsic non-linear behavior (e.g.,​‌ wind turbine structures), or​​ damages to be monitored​​​‌ can induce non-linear behavior​ (e.g., cracks, joints). It​‌ is therefore the objective​​ to investigate and to​​​‌ consider relevant non-linear phenomena​ in structural analysis and​‌ monitoring methods. On the​​ other side, the structural​​​‌ design itself is an​ objective in the context​‌ of monitoring, e.g., for​​ meta-structure engineering with designed​​​‌ properties regarding vibration and​ noise – and their​‌ monitoring –, or more​​ general, for coupling design​​​‌ with monitoring for the​ conception of smart structures​‌.

With the structural​​ modeling at hand, it​​​‌ is the objective to​ conceive statistical methods that​‌ fuse data and models​​ for an advanced assessment​​​‌ of the structural state.​ The overall goal is​‌ to conceive techniques for​​ digital twins, based on​​​‌ real-time multi-physics and multi-data​ analysis integrating diverse measurement​‌ sources for a complete​​ structural assessment.

Being a​​​‌ multidisciplinary team with strong​ applications in engineering, we​‌ have the general objective​​ to develop theoretical methods​​​‌ that are motivated by​ applications, and to deliver​‌ their proofs of concepts​​ on laboratory and field​​​‌ applications, including the development​ of demonstrators and their​‌ transfer to industrial partners.​​

3 Research program

The​​​‌ scientific challenges to achieve​ our objectives of SHM​‌ are addressed by five​​ research axes of the​​​‌ team:

Axis 1: Sensor​ technologies and data harvesting​‌ concerns the characterization and​​ usage of new sensor​​​‌ technologies for monitoring. An​ important topic is the​‌ exploitation of data for​​ subsequent monitoring methods, e.g.,​​​‌ by developing image processing​ methods for active or​‌ passive imaging in the​​ visible or infrared range.​​ Another challenge is smart​​​‌ sensing, e.g., with self-diagnosis‌ of sensors on the‌​‌ quality of the measured​​ signals over time.

Axis​​​‌ 2: Complex physical models‌ for structural analysis and‌​‌ design focuses on multi-physics​​ modeling. The challenge is​​​‌ to understand various phenomena‌ occurring at different scales‌​‌ in structures, in order​​ to optimize their design,​​​‌ performance, identification and monitoring.‌ The fields and scales‌​‌ of physics intersect in​​ these issues, including couplings​​​‌ between mechanical and thermal‌ behavior, or dynamics and‌​‌ acoustics. The approaches to​​ be developed make extensive​​​‌ use of numerical resolution‌ schemes and multi-scale or‌​‌ model reduction methods.

Axis​​ 3: Advanced data analysis​​​‌ for complex systems concerns‌ processing techniques of measurement‌​‌ data to infer structural​​ properties under simplifying assumptions​​​‌ (e.g., linear model structure)‌ and without the use‌​‌ of physical model properties.​​ The challenge is to​​​‌ extract relevant information for‌ characterizing a structure (e.g.,‌​‌ vibration mode) or a​​ material (e.g., wave velocity,​​​‌ permittivity) under environmental nuisance,‌ and to track these‌​‌ parameters over time, which​​ enables data-driven monitoring. This​​​‌ calls for statistical system‌ identification and Bayesian filtering‌​‌ techniques, as well as​​ AI-based processing tools.

Axis​​​‌ 4: Joint data/model analysis‌ – digital twin focuses‌​‌ on fusing measurement data​​ with physical model information​​​‌ for an advanced structural‌ assessment. The main challenge‌​‌ is the optimal processing​​ of information from various​​​‌ sources (multi-physics modeling, data‌ from different kinds of‌​‌ sensors) under both model​​ and estimation uncertainties, and​​​‌ at different scales (material,‌ component, whole system). Physics-informed‌​‌ machine learning will play​​ an important role.

Axis​​​‌ 5: Predictive analysis concerns‌ the prognosis of future‌​‌ behavior of the monitored​​ system. A first challenge​​​‌ is the predictive analysis‌ of the actual diagnosis‌​‌ performance, i.e., detectability or​​ identifiability, of an employed​​​‌ monitoring system (comprising sensors‌ and diagnosis methods), while‌​‌ data from damaged systems​​ is usually never available​​​‌ in advance, models are‌ flawed, and sensors are‌​‌ degrading over time. This​​ leads to structural performance​​​‌ assessment, where the ultimate‌ goal is the prediction‌​‌ of the remaining useful​​ service life.

4 Application​​​‌ domains

The theoretical and‌ technological developments of the‌​‌ team are motivated by​​ structural health monitoring applications.​​​‌ An important application focus‌ is on the assessment‌​‌ of civil structures like​​ bridges or buildings, as​​​‌ well as wind turbine‌ monitoring. In general, infrastructure‌​‌ is of interest, including​​ urban structures (heat islands),​​​‌ railway structures or energy‌ related infrastructures (cables, power‌​‌ lines).

Besides these more​​ classic application domains of​​​‌ the team, the design‌ and monitoring of advanced‌​‌ structures and materials is​​ an emerging topic, with​​​‌ applications to various industries‌ (e.g., transportation, aerospace, naval‌​‌ and civil engineering). One​​ can mention the development​​​‌ of lightweight locally resonant‌ material concepts to enhance‌​‌ the sound transmission loss​​ in an aircraft fuselage,​​​‌ or the material identification‌ of composite structures using‌​‌ non-contact measurement techniques. Furthermore,​​ the modeling and optimization​​​‌ of novel mechanical architectures‌ able to mitigate low-frequency‌​‌ and/or seismic loads is​​ a promising research avenue.​​​‌ The design and analysis‌ of materials with particular‌​‌ properties for heat transfer,​​​‌ like porous media and/or​ phase change materials, becomes​‌ of interest, with applications​​ to thermal regulation of​​​‌ materials, structures or urban​ districts. Another advantage of​‌ these enhanced properties is​​ their use and analysis​​​‌ under ambient thermal loading,​ revealing information about structure​‌ through a different prism:​​ a structural health via​​​‌ energetic monitoring. Furthermore, the​ analysis and monitoring of​‌ non-linear phenomena on structures,​​ e.g., due to contact,​​​‌ friction, slender geometries or​ interactions between various physics​‌ (e.g., fluid structure interactions)​​ are emerging, with applications​​​‌ to wind turbines, railways,​ mechanical or aeronautical systems,​‌ among others. Last but​​ not least, the ongoing​​​‌ collaboration with the Hycomes​ team paves the way​‌ toward the health monitoring​​ and optimal control of​​​‌ complex multi- and cyberphysical​ systems such as power​‌ grids and urban heating​​ networks.

Thanks to the​​​‌ interaction between physical models​ and data, the developed​‌ techniques are rarely limited​​ to a particular structure.​​​‌ The methodological expertise of​ the team could also​‌ open up to applications​​ in completely new areas,​​​‌ like for monitoring bio-mechanical​ structures and engineering components,​‌ ranging from the nanoscopic​​ (e.g., crystals) to the​​​‌ macroscopic scales (e.g., seismic).​

5 Highlights of the​‌ year

The I4S team​​ has organized the IOMAC​​​‌ 2025 conference at the​ Inria Rennes conference center​‌ from May 20–23, 2025,​​ attracting 150 participants.

5.1​​​‌ Awards

  • Former PhD student​ Cédric Bertolt Nzouatchoua was​‌ awarded the Special Mention​​ “Environmental Sensitivity and Innovation”​​​‌ in the 2025 Thesis​ Prize of the Le​‌ Mans University Foundation.
  • PhD​​ student Lucas Rouhi got​​​‌ the Best PhD Paper​ Award for the article​‌ "Controlling dispersion in lattice​​ waveguides using positive-stiffness-only non-local​​​‌ interactions" 54 at the​ 16th International Conference on​‌ Vibration Problems (ICOVP-2025) &​​ 11th International Conference on​​​‌ Wave Mechanics and Vibrations​ (WMVC-2025), held in Lisbon,​‌ Portugal, on September 2–5,​​ 2025

6 Latest software​​​‌ developments, platforms, open data​

6.1 Latest software developments​‌

6.1.1 Supervisor

  • Name:
    Supervisor​​
  • Keywords:
    Middleware, Sensors, Python,​​​‌ Digital twin, SHM (Structural​ Health Monitoring), Control system​‌
  • Functional Description:
    Supervisor is​​ a middleware designed for​​​‌ efficiently handling data fetched​ from sensors or online​‌ sources, backing up this​​ data in a secure​​​‌ manner, and launching calculation​ programs in a synchronized​‌ way.
  • Release Contributions:
    First​​ complete version.
  • Contact:
    Jean​​​‌ Dumoulin
  • Participants:
    Jean Dumoulin,​ Thibaud Toullier, Mathias Malandain,​‌ 3 anonymous participants
  • Partner:​​
    Université Gustave Eiffel

6.1.2​​​‌ Spycic

  • Name:
    Spycic library​
  • Keywords:
    Python, C++, Binding​‌
  • Scientific Description:
    Spycic is​​ a header-only C++ library​​​‌ for fetching and calling​ Python functions from C++​‌ code. Designed as a​​ wrapper of the C/Python​​​‌ API, Spycic strongly relies​ on variadic templates to​‌ make it possible to​​ call in a simple​​​‌ way Python functions with​ different signatures and an​‌ arbitrary number of arguments.​​ GIL handling, exception handling​​​‌ and type casting are​ performed under the hood,​‌ so as to make​​ use as simple as​​​‌ possible.
  • Functional Description:

    The​ Spycic (Simple Python Calls​‌ In C++) header-only library​​ is a wrapper around​​​‌ the C/Python API that​ provides a handful of​‌ functions allowing for simple​​ calls to Python functions​​ from a C++ code.​​​‌ Python functions to be‌ used may be declared‌​‌ in several *independent* source​​ files.

    Spycic provides the​​​‌ following functions:

    * `fetchFunction(const‌ char* functionName, const char*‌​‌ sourceCode)` is used to​​ fetch the Python function​​​‌ called `functionName` from a‌ given Python code `sourceCode`‌​‌ provided as a C-style​​ string. The function is​​​‌ returned as a `PyObject*`.‌ * `fetchFunction(const char* functionName,‌​‌ std::string& sourceCode)` is used​​ to fetch the Python​​​‌ function called `functionName` from‌ a given Python code‌​‌ `sourceCode` provided as a​​ `std::string`. The function is​​​‌ returned as a `PyObject*`.‌ * `runFunction<returnType>(PyObject* func, Values...‌​‌ values)` is used to​​ call a Python function​​​‌ (imported as a `PyObject*`)‌ with an arbitrary number‌​‌ of arguments. The return​​ type has to be​​​‌ specified as a template‌ argument, for example, `runFunction<double>(f,‌​‌ arg1, arg2)`. The return​​ type can be `void`,​​​‌ as in `runFunction<void>(f, arg1,‌ arg2)`. All necessary operations‌​‌ (GIL handling, formatting, type​​ castings, etc.) are performed​​​‌ under the hood. The‌ arguments are provided as‌​‌ C++ POD (Plain Old​​ Data) values and/or `std::vector`​​​‌ containers, and the output‌ (if any) is a‌​‌ C++ POD or vector​​ as well.

    A fresh​​​‌ exception class called 'PythonError'‌ is also defined in‌​‌ order to handle errors​​ that occur during calls​​​‌ to functions provided by‌ the C/Python API itself.‌​‌

    Client code must still​​ call functions `Py_Initialize()` and​​​‌ `Py_Finalize()` to be able‌ to use the Python‌​‌ interpreter.

  • Release Contributions:
    The​​ handling of `std::vector` objects​​​‌ (containing floating point numbers‌ or integers) as both‌​‌ function inputs and function​​ outputs, and the handling​​​‌ of functions returning `void`,‌ were added since version‌​‌ 0.1.
  • News of the​​ Year:
    Regroupement sous la​​​‌ forme d'une bibliothèque header-only,‌ appels transparents de fonctions‌​‌ ne retournant aucune valeur,​​ vérification des overflows lors​​​‌ du casting de valeurs‌ de retour (Python vers‌​‌ C), mémoisation pour l'import​​ des modules, pipeline CI,​​​‌ passage en REUSE-compliant en‌ vue d'une ouverture open‌​‌ source.
  • Contact:
    Mathias Malandain​​
  • Participant:
    Mathias Malandain

6.1.3​​​‌ PythonFMUGenerator

  • Keywords:
    Cosimulation, FMI,‌ Cyber-physical systems
  • Scientific Description:‌​‌
    PythonFMUGenerator is a tool​​ for the automatic encapsulation​​​‌ of Python code into‌ C++-based standardized cosimulation units‌​‌ (FMUs). It only relies​​ on a Python source​​​‌ file and a JSON‌ description of the properties‌​‌ of the generated FMU.​​ This makes it possible​​​‌ to integrate on-demand FMU‌ generation to a system‌​‌ model assembly and simulation​​ pipeline, contrary to existing​​​‌ tools that create templates‌ to be populated by‌​‌ hand before compilation and​​ FMU generation.
  • Functional Description:​​​‌

    FMI is a fast-growing‌ standard for the cosimulation‌​‌ of large mutli- and​​ cyberphysical system models. It​​​‌ relies on the encapsulation‌ of source code, written‌​‌ in various tools and​​ languages, into cosimulation units​​​‌ called FMUs that share‌ a common interface. However,‌​‌ the encapsulation of Python​​ code into an FMU​​​‌ is still a technical‌ challenge that very few‌​‌ tools try to address.​​

    PythonFMUGenerator is a tool​​​‌ for the automatic encapsulation‌ of Python code into‌​‌ C++-based FMUs for cosimulation.​​ It only relies on​​​‌ a Python source file‌ and a JSON description‌​‌ of the properties of​​​‌ the generated FMU. This​ makes it possible to​‌ integrate on-demand FMU generation​​ to a system model​​​‌ assembly and simulation pipeline,​ contrary to existing tools​‌ that create templates to​​ be populated by hand​​​‌ before compilation and FMU​ generation.

    PythonFMUGenerator relies on​‌ the Spycic library (from​​ the same author), that​​​‌ acts as a wrapper​ around the C/Python API​‌ so as to considerably​​ simplify Python function calls​​​‌ from C or C++​ code. It is based​‌ on FMICodeGenerator, a tool​​ developed by Andreas Nicolai​​​‌ (ghorwin) and coworkers, itself​ under a BSD3 license.​‌

  • News of the Year:​​
    Passage au standard FMI3​​​‌ (API intégrale + logiques​ d'exécution pour l'initialisation, l'avancement​‌ temporel et l'entrée/sortie de​​ valeurs de tous les​​​‌ types gérés par le​ standard), gestion des vecteurs​‌ en entrées/sorties des FMU,​​ pipeline CI pour de​​​‌ nombreux tests de l'intégralité​ de la chaîne de​‌ génération des FMU.
  • Contact:​​
    Mathias Malandain
  • Participants:
    Benoit​​​‌ Caillaud, Mathias Malandain, Thibaud​ Toullier

7 New results​‌

7.1 Sensor technologies and​​ data harvesting

7.1.1 Strain​​​‌ Transfer Modeling and Post-Processing​ for Distributed Fiber Optic​‌ Sensors

Participants: Mira Kabbara​​, Xavier Chapeleau,​​​‌ Qinghua Zhang.

Distributed​ fiber optic sensors are​‌ widely used in structural​​ health monitoring due to​​​‌ their high spatial resolution.​ Accurate interpretation of their​‌ measurements requires careful consideration​​ of strain transfer through​​​‌ protective coatings. A simplified​ one-dimensional strain transfer model,​‌ incorporating a strain lag​​ parameter dependent on cable​​​‌ properties and installation conditions,​ has been commonly used.​‌ This study extends the​​ model to robust four-layered​​​‌ cables, including steel-reinforced and​ polymer-coated designs, and assesses​‌ its performance under strain​​ gradients using finite element​​​‌ simulations. Results show that​ the model accurately predicts​‌ strain in steel-reinforced cables​​ but is less precise​​​‌ for polymer-coated cables, highlighting​ the importance of interlayer​‌ stiffness and strain lag​​ calibration.

To enable practical​​​‌ use in high-resolution measurements,​ efficient post-processing algorithms are​‌ developed to solve the​​ 1D strain transfer equation​​​‌ and its inverse problem.​ These methods allow rapid​‌ reconstruction of the actual​​ strain profile from raw​​​‌ sensor data, supporting applications​ such as real-time vibration​‌ analysis and structural health​​ monitoring. Together, the modeling​​​‌ and post-processing framework improves​ both the accuracy and​‌ usability of fiber optic​​ sensors in complex environments.​​​‌ 24, 47

7.1.2​ Subpixel motion estimation for​‌ video-based target-free vibration monitoring​​ under complex environmental conditions​​​‌

Participants: Zhilei Luo,​ Boualem Merainani, Vincent​‌ Baltazart, Qinghua Zhang​​, Michael Doehler.​​​‌

An emerging technique to​ measure structural vibrations is​‌ based on motion signals​​ extracted from video images.​​​‌ The use of video​ cameras offers multiple advantages​‌ over traditional mechanical sensors:​​ contactless measurement, large coverage,​​​‌ easy installation and maintenance.​ This work proposes a​‌ new method for real-time​​ motion signal extraction from​​​‌ video images with subpixel​ accuracy. It aims to​‌ address the challenges posed​​ by complex operating conditions,​​​‌ namely illumination variations and​ background interference. Illumination robustness​‌ is achieved by efficiently​​ combining image intensity interpolation​​​‌ with an affine brightness​ and contrast tuning transformation.​‌ Background robustness is obtained​​ by automatically selecting active​​ pixels in the processed​​​‌ images. Moreover, the on-line‌ numerical computations are fast‌​‌ enough for real-time applications.​​ Results of theoretical analysis​​​‌ ensure that the considered‌ optimization criteria are well-posed‌​‌ and that, in the​​ main step of subpixel​​​‌ motion estimation, the involved‌ nonlinear optimization problem is‌​‌ efficiently solved in closed-form​​ through a linear least​​​‌ squares problem. The performance‌ of the proposed method‌​‌ is evaluated both on​​ simulated images and on​​​‌ laboratory experiments with a‌ target-free cantilever beam in‌​‌ comparison with existing methods.​​ The reported results demonstrate​​​‌ the robustness and computational‌ efficiency of the proposed‌​‌ method under complex environmental​​ conditions, allowing real-time computation​​​‌ on a standard laptop‌ for vibration monitoring with‌​‌ more than 100 virtual​​ sensors at 600 frames​​​‌ per second. 25

7.1.3‌ Monitoring for sustainable and‌​‌ inclusive urban areas

Participants:​​ Jean Dumoulin.

Urban​​​‌ resilience requires continuous monitoring‌ of critical services and‌​‌ infrastructure to respond effectively​​ to hazards and multi-risk​​​‌ scenarios, including climate change‌ and pandemics. Advanced monitoring‌​‌ approaches now integrate Earth​​ observation, positioning, navigation, ICT​​​‌ technologies, and citizen-sourced or‌ “non-sensor” data to enhance‌​‌ situational awareness. By combining​​ these diverse data streams​​​‌ and processing them with‌ artificial intelligence and high-performance‌​‌ computing, cities can achieve​​ more informed intervention planning,​​​‌ improved service continuity, and‌ ultimately safer, smarter, and‌​‌ more inclusive urban environments.​​ 55

7.1.4 Ozone Concentration​​​‌ Estimation from Infrared Images‌ Using Extinction Coefficient

Participants:‌​‌ Jean Dumoulin.

Air​​ quality assessment requires concentration​​​‌ measurement of various polluting‌ gases, typically requiring multiple‌​‌ expensive sensors, each dedicated​​ to a specific pollutant.​​​‌ Therefore, there is a‌ need for costeffective sensors‌​‌ capable of detecting one​​ or more pollutants, with​​​‌ less reliability, such as‌ camera-based sensors, but enabling‌​‌ denser sampling. In this​​ work, we investigate how​​​‌ the extinction coefficients estimated‌ from an infrared camera‌​‌ may be useful for​​ predicting ground-level ozone concentration.​​​‌ In addition to these‌ coefficients, we show how‌​‌ weather and pollution measures​​ collected from stations near​​​‌ the studied area are‌ useful, with different machine‌​‌ learning methods, to better​​ predict ozone concentration. The​​​‌ performance of the models‌ is validated through a‌​‌ comprehensive evaluation using MAE,​​ RMSE and R-Squared metrics.​​​‌ Parameter selection methods are‌ also used to study‌​‌ the impact of different​​ meteorological parameters and other​​​‌ pollutant concentrations on the‌ prediction of ozone concentration.‌​‌ 42

7.1.5 Outdoor Hybrid​​ Solar Road Demonstrator Monitoring​​​‌ Using Infrared Thermography with‌ Embedded Local Probes for‌​‌ Energy Harvesting Performance Evaluation​​

Participants: Jean Dumoulin,​​​‌ Domenico Vizzari, Lucas‌ Czamanski Meireles, Thibaud‌​‌ Toullier.

This study​​ investigates, in a natural​​​‌ environment, the thermal behavior‌ of an innovative pavement‌​‌ system with thermal and​​ solar energy collection functionalities.​​​‌ The whole structure is‌ continuously monitored using temperature‌​‌ and heat flux sensor​​ probes integrated inside the​​​‌ structure. Local weather conditions‌ are also monitored. Infrared‌​‌ Thermography is used as​​ a complementary non-invasive technique​​​‌ to monitor temperature surface‌ distributions with time and‌​‌ assess the efficiency of​​ heat transfer within the​​​‌ pavement structure. All sensors‌ are connected to a‌​‌ newly developed platform that​​​‌ centralized data access, visualization,​ and storage, enabling seamless​‌ management and user interactions.​​ The obtained results are​​​‌ presented and discussed. 43​

7.1.6 Comparative study of​‌ image quality acquired on​​ a new portable dynamic​​​‌ laboratory test bench using​ two thermal time constant​‌ uncooled IRFPA microbolometric camera​​

Participants: Boualem Merainani,​​​‌ Thibaud Toullier, Jean​ Dumoulin.

An experimental​‌ setup dedicated to assessing​​ and comparing the image​​​‌ quality of uncooled IRFPA​ microbolometer cameras with different​‌ thermal time constants has​​ been designed and realized.​​​‌ Initially, we explored a​ concept involving heated objects​‌ mounted on two opposing​​ arms rotating at different​​​‌ temperatures; However, practical constraints,​ such as the need​‌ for electrical brushes to​​ transfer current, as well​​​‌ as significant challenges related​ to mass balance and​‌ installation complexity, made this​​ approach impractical. Consequently, we​​​‌ adopted a new solution​ comprising fixed thermal panels​‌ and a self-designed rotating​​ disk inspired by optical​​​‌ choppers. We designed the​ test bench to be​‌ compact and portable, enhancing​​ its versatility and making​​​‌ it adaptable to various​ testing environments. Figure 1​‌ illustrates both the CAD​​ design and the real​​​‌ implementation of the test​ bench. 51

7.1.7 PEGASE4​‌ : a generic board​​ for embedded SHM applications​​​‌

Participants: Vincent Le Cam​, Arthur Bouché,​‌ Adji Toure, Antoine​​ Barre, Lucas Doula​​​‌.

This work presents​ the latest version of​‌ PEGASE, a versatile wireless​​ board designed for Structural​​​‌ Health Monitoring (SHM) applications.​ The first part highlights​‌ the technological advances of​​ PEGASE, including its generic​​​‌ processing capabilities with an​ embedded Buildroot Linux system,​‌ an inertial measurement unit​​ (IMU), GNSS receivers, and​​​‌ multiple I/O interfaces. The​ discussion then focuses on​‌ key scientific innovations, such​​ as the novel use​​​‌ of the GNSS/PPS signal​ to achieve microsecond-level synchronization​‌ within Linux, and energy​​ management strategies optimized for​​​‌ efficient battery and solar-cell​ usage. Finally, practical SHM​‌ applications are presented to​​ illustrate PEGASE in action,​​​‌ including its deployment in​ a wireless acoustic emission​‌ monitoring system. 48

7.1.8​​ Advanced optical and distributed​​​‌ sensing for monitoring interfaces​ and structural behavior

Participants:​‌ Arij Fawaz, Xavier​​ Chapeleau.

Recent developments​​​‌ in fiber-optic and distributed​ sensing technologies are enabling​‌ new strategies for monitoring​​ interfaces, durability, and load​​​‌ transfer mechanisms across structural​ and material systems. These​‌ contributions illustrate how embedded​​ and bonded optical sensors​​​‌ can provide high-resolution measurements​ under static, cyclic, and​‌ dynamic loading conditions.

Fiber​​ Bragg Grating (FBG) sensors​​​‌ were embedded in castable​ polyurethane resins to evaluate​‌ their suitability for ultrasonic​​ applications. The study examined​​​‌ strain evolution during polymerization​ and showed spectral shifts​‌ of up to 10​​ nm, highlighting the need​​​‌ to account for material​ shrinkage when selecting interrogation​‌ wavelengths. After curing, FBGs​​ successfully detected 100 kHz​​​‌ ultrasonic waves, with acrylate​ and polyimide coatings transmitting​‌ comparable energy to the​​ fiber core, and preliminary​​​‌ signs of possible crosstalk​ between gratings. These results​‌ confirm the feasibility of​​ using embedded FBGs for​​​‌ ultrasonic sensing in castable​ materials. 21

A new​‌ adhesively bonded specimen configuration​​ was developed to allow​​ both creep testing and​​​‌ fracture-mechanics characterization within the‌ same geometry. The End-Loaded‌​‌ Split (ELS) test was​​ adapted for mode II​​​‌ fracture, while the creep‌ frame ensured a constant‌​‌ stress state in the​​ adhesive layer. Digital Image​​​‌ Correlation and optical fiber‌ sensors were used together‌​‌ to monitor crack propagation​​ and evaluate energy release,​​​‌ enabling more consistent assessment‌ of bonded joints before‌​‌ and after creep aging.​​ 44

Full-scale experimental pavement​​​‌ sections were instrumented to‌ study the response of‌​‌ surface layers under different​​ axle configurations and interface​​​‌ bonding conditions. Strain gauges‌ and embedded optical fibers‌​‌ placed at several depths​​ captured the influence of​​​‌ temperature, wheel interaction, and‌ debonding on strain fields.‌​‌ Tridem axles generated higher​​ strains than single axles,​​​‌ and interface debonding led‌ to tensile strains at‌​‌ the bottom of the​​ surface layer, contrasting with​​​‌ compressive strains in well-bonded‌ cases. Numerical simulations using‌​‌ Viscoroute 2.0 supported the​​ interpretation of these measurements.​​​‌ 18

Finally, the bond‌ behavior of thermoplastic GFRP‌​‌ rebars embedded in concrete​​ was examined through pull-out​​​‌ testing. The effects of‌ rebar diameter and surface‌​‌ geometry on force–displacement response​​ and average pull-out strength​​​‌ were analyzed, and some‌ specimens were equipped with‌​‌ optical fiber cables to​​ record strain distributions along​​​‌ the interface in real‌ time. Comparisons with thermoset‌​‌ GFRP and conventional steel​​ reinforcement provided further insight​​​‌ into differences in bond‌ mechanisms and durability potential.‌​‌ 45

7.2 Complex physical​​ models for structural analysis​​​‌ and design

7.2.1 Optimizing‌ bifurcations and singularities for‌​‌ performance enhancement and mitigation​​ of the adverse dynamics​​​‌ of nonlinear energy sinks‌

Participants: Adrien Mélot.‌​‌

This work introduces a​​ general computational framework for​​​‌ optimizing the performances and‌ mitigating the adverse dynamics‌​‌ of nonlinear energy sinks​​ (NESs) under harmonic external​​​‌ forcing. It is well‌ known that attaching small,‌​‌ essentially nonlinear, subsystems to​​ a linear host system​​​‌ can provide efficient passive‌ vibration mitigation. However, the‌​‌ introduced nonlinearity can induce​​ adverse dynamics, in the​​​‌ form of isolated response‌ curves, which are detrimental‌​‌ to the performances of​​ the system. Several multi-objective​​​‌ optimization problems are formulated,‌ which consist in minimizing‌​‌ objective functionals derived from​​ bifurcation and singularity theory​​​‌ in order to control‌ such phenomena and improve‌​‌ the performances of NESs.​​ The methodology is demonstrated​​​‌ on a two-degree-offreedom system‌ consisting of a linear‌​‌ oscillator coupled to a​​ nonlinear energy sink with​​​‌ cubic stiffness. However, its‌ fully computational nature makes‌​‌ it applicable to arbitrarily​​ complex NES configurations and​​​‌ lays the foundation for‌ extending the design optimization‌​‌ of NESs to full​​ finite element models. These​​​‌ results are compared to‌ those obtained with the‌​‌ inclusion of a nonlinear​​ damping term, which is​​​‌ a common way of‌ mitigating the issue of‌​‌ isolated response curves in​​ the literature. We report​​​‌ significant computational speedups compared‌ to existing methodologies for‌​‌ controlling isolated response curves​​ induced by nonlinear energy​​​‌ sinks. 30, 60‌

7.2.2 An efficient neural‌​‌ network-based surrogate model for​​ predicting static gear contact​​​‌ conditions

Participants: Adrien Mélot‌.

Gears are an‌​‌ essential component of numerous​​​‌ mechanical systems across a​ wide range of engineeringapplications.​‌ However, they may be​​ associated to high levels​​​‌ of radiated noise which​ can limit their use.Accurately​‌ predicting this noise is​​ of paramount importance for​​​‌ the design, optimization and​ health mon-itoring of gear​‌ transmissions. System identification is​​ therefore needed to reach​​​‌ a sufficiently high levelof​ accuracy. However, this usually​‌ comes at the cost​​ of high computational burden.​​​‌ Using traditionalmodeling assumptions, it​ is widely accepted that​‌ the radiated noise stems​​ from the dynamic response​​​‌ ofthe gears which is​ itself induced by the​‌ static transmission error (STE)​​ and time-varying mesh stiffness.These​​​‌ physical quantities are governed​ by the local contact​‌ conditions between the gear​​ teeth. An accu-rate computation​​​‌ of these physical quantities​ is therefore crucial. However,​‌ this is a difficult​​ problem asgear contact resolution​​​‌ is intrinsically nonlinear and​ multiscale. Even considering simplifying​‌ assump-tions, the computation of​​ this physical quantities entails​​​‌ a significant computational effort​ when coupledto optimization procedures.​‌ In this work, we​​ introduce an efficient neural​​​‌ network-based surrogate modelfor predicting​ static gear contact conditions​‌ in near real time​​ in order to facilitate​​​‌ the identification andoptimization of​ mechanical systems equipped with​‌ geared systems. 52

7.2.3​​ Computing the dynamic response​​​‌ of periodic waveguides with​ nonlinear boundaries using the​‌ Wave Finite Element Method​​

Participants: Vincent Mahé,​​​‌ Adrien Mélot, Christophe​ Droz.

Nonlinear effects​‌ are increasingly relevant in​​ modern mechanical systems due​​​‌ to lighter, slender structures​ and the desire to​‌ exploit nonlinearities for enhanced​​ performance. Accurately capturing these​​​‌ effects is challenging, as​ numerical models of periodic​‌ waveguides can involve millions​​ of degrees of freedom,​​​‌ and localized nonlinearities further​ complicate simulations. This work​‌ proposes an extension of​​ the Wave Finite Element​​​‌ Method (WFEM) that combines​ Floquet-Bloch theory with finite-element​‌ discretisation of complex unit​​ cells, enabling efficient computation​​​‌ of the dynamic response​ of periodic waveguides with​‌ nonlinear boundaries. Nonlinear forces​​ are treated via an​​​‌ alternating frequency-time procedure and​ higher harmonics are captured​‌ using the Harmonic Balance​​ Method, with the system​​​‌ solved through numerical continuation.​

The method reduces problem​‌ size while providing richer​​ physical insight than classical​​​‌ finite element approaches. Validation​ against standard FEM with​‌ Craig-Bampton reduction shows excellent​​ agreement and an 83%​​​‌ reduction in computational time.​ Application to a locally​‌ resonant metamaterial demonstrates that​​ nonlinear effects can shift​​​‌ band-edge resonances into bandgaps,​ producing high-amplitude, spatially localised​‌ vibrations not predicted by​​ linear theory. This approach​​​‌ offers a versatile and​ efficient framework for simulating​‌ complex metamaterials, civil engineering​​ structures, and other systems​​​‌ with nonlinear interfaces or​ singularities, supporting system identification,​‌ R&D cycles, and digital​​ twinning applications. 29,​​​‌ 50, 59

7.2.4​ Reduced Frequency-driven Bloch Wave​‌ Decomposition for Harmonic Analysis​​ of Finite Periodic Structures​​​‌

Participants: Christophe Droz,​ Alvaro Gavilan Rojas.​‌

A frequency-driven, reduced wave​​ finite element method is​​​‌ proposed for periodic structures​ which are solely defined​‌ by their dynamic stiffness​​ matrices. Using an S-S​​​‌-1 transform combined​ with an adaptive eigenvector​‌ sampling and a ω-driven​​ Bloch wave decomposition, we​​ achieve dispersion and harmonic​​​‌ analyses with enhanced accuracy‌ and efficiency. 36

7.2.5‌​‌ Controlling dispersion in lattice​​ waveguides using positive-stiffness-only non-local​​​‌ interactions

Participants: Lucas Rouhi‌, Christophe Droz.‌​‌

This study presents a​​ systematic approach to engineering​​​‌ the dispersion relation of‌ one-dimensional monoatomic lattices through‌​‌ the use of long-range​​ interactions constrained to strictly​​​‌ positive stiffness values. Departing‌ from classical cosine fitting‌​‌ techniques, the proposed framework​​ employs interpolation at prescribed​​​‌ frequency-wave number pairs, leading‌ to a linear system‌​‌ formulation. The stiffness coefficients​​ are then determined using​​​‌ non-negative least squares, ensuring‌ the physical admissibility of‌​‌ the design. This method​​ enables the realization of​​​‌ dispersion curves featuring nonstandard‌ characteristics, such as negative‌​‌ group velocity, roton-like stationary​​ points, or locally flat​​​‌ bands, without resorting to‌ non-physical parameters. The concept‌​‌ of admissibility domains is​​ introduced to characterize the​​​‌ feasible set of target‌ values under positivity constraints,‌​‌ and several numerical examples​​ illustrate the trade-offs between​​​‌ design flexibility and physical‌ realizability. The framework provides‌​‌ a versatile tool for​​ the inverse design of​​​‌ dispersion in non-local lattices,‌ with potential extensions to‌​‌ higher-dimensional and multi-physical systems.​​ 54

7.2.6 Adjustable surface​​​‌ tension independent of the‌ collision operator for pseudo-potential‌​‌ lattice Boltzmann methods

Participants:​​ Romain Noel.

In​​​‌ this work, we propose‌ an alternative surface tension‌​‌ adjustment approach in the​​ pseudo-potential lattice Boltzmann (LB)​​​‌ model, which is not‌ only decoupled from the‌​‌ density ratio but also​​ independent of the collision​​​‌ operator. This is achieved‌ by incorporating a generic‌​‌ source term obtained from​​ the difference between a​​​‌ modified moment equilibrium and‌ an original moment equilibrium‌​‌ distribution function in the​​ LB equation. The explicit​​​‌ form of the source‌ term is obtained through‌​‌ a third-order Chapman-Enskog analysis​​ of the LB equation,​​​‌ aiming to recover the‌ targeted governing equations from‌​‌ a modified Landau free​​ energy theory using a​​​‌ hybrid density-pseudo-potential form. The‌ source term can be‌​‌ easily and straightforwardly incorporated​​ into different widely used​​​‌ collision operators, such as‌ single relaxation time (SRT‌​‌ or LBGK), multiple relaxation​​ time (MRT) and entropic-MRT​​​‌ (KBC) operators. The proposed‌ method is validated by‌​‌ three benchmarks: (i) the​​ liquid-gas co-existence density, (ii)​​​‌ surface tension adjustment via‌ the static droplet case‌​‌ and (iii) droplet deformation​​ via oscillations. It is​​​‌ shown that thermodynamic consistency‌ is restored in a‌​‌ large range of temperature​​ ratio, and, moreover, a​​​‌ remarkable tunable surface tension‌ range of 140 times‌​‌ can be achieved. Benefiting​​ from the proposed surface​​​‌ tension adjustment method, we‌ have successfully modeled the‌​‌ droplet impact and splashing​​ dynamics with a Weber​​​‌ number up to 10‌ 500, achieving one order‌​‌ of magnitude higher than​​ LB simulations reported in​​​‌ the literature. 31

7.2.7‌ Topology Optimization of Isolated‌​‌ Response Curves in 3D​​ Geometrically-nonlinear Beam

Participants: Adrien​​​‌ Mélot.

Topology optimisation‌ is a powerful tool‌​‌ for designing efficient and​​ light structures. However, classical​​​‌ topology optimisation methods (SIMP,‌ LSF), which are gradient-based,‌​‌ are not adapted to​​ deal with nonlinear vibrations​​​‌ in the context of‌ geometrical nonlinearities as the‌​‌ simulation of such systems​​​‌ is computationally expensive, and​ the strong nonlinearbehaviour makes​‌ the objective function non-convex​​ with many local minima.​​​‌ The present work investigates​ the potential of using​‌ global optimisation methods to​​ topology optimise those structures.​​​‌ To provide more robust​ nonlinear features in the​‌ optimisation, the bifurcations are​​ directly tracked and optimised.​​​‌ The strategy is applied​ to a 3D finite​‌ element model of a​​ beam 41

7.3 Advanced​​​‌ data analysis for complex​ systems

7.3.1 Variance estimation​‌ of modal parameters from​​ the poly-reference least-squares complex​​​‌ frequency-domain algorithm

Participants: Mikkel​ Tandrup Steffensen, Michael​‌ Doehler.

Modal parameter​​ estimation from input/output data​​​‌ is a fundamental task​ in engineering. The poly-reference​‌ least-squares complex frequency-domain (pLSCF)​​ algorithm is a fast​​​‌ and robust method for​ this task, and is​‌ extensively used in research​​ and industry. As with​​​‌ any method using noisy​ measurement data, the modal​‌ parameter estimates are afflicted​​ with uncertainty. However, their​​​‌ uncertainty quantification has been​ incomplete, in particular for​‌ the case of real-valued​​ polynomial coefficients in the​​​‌ modelling of the frequency​ response functions (FRFs) in​‌ the pLSCF algorithm, and​​ no expressions have been​​​‌ available for the covariance​ of participation vectors and​‌ mode shapes that are​​ subsequently estimated with the​​​‌ least-squares frequency domain (LSFD)​ approach. This work closes​‌ these gaps. Uncertainty expressions​​ for the modal parameters,​​​‌ including participation vectors and​ mode shapes, are derived​‌ and presented. It is​​ shown how to estimate​​​‌ the covariance between different​ modal parameters, and a​‌ complete method is provided​​ for modal parameter covariance​​​‌ estimation from pLSCF. The​ method is propagating the​‌ uncertainty of FRFs through​​ the algorithm using first-order​​​‌ perturbation theory and the​ delta method. The method​‌ is validated via extensive​​ Monte-Carlo simulations and the​​​‌ applicability is illustrated using​ a laboratory experiment. 34​‌

7.3.2 New joint estimation​​ method for emissivity and​​​‌ temperature distribution based on​ a Kriged Marginalized Particle​‌ Filter : application to​​ simulated infrared thermal image​​​‌ sequences

Participants: Thibaud Toullier​, Jean Dumoulin,​‌ Laurent Mevel.

This​​ work addresses the challenge​​​‌ of simultaneously estimating temperature​ and emissivity for infrared​‌ thermography in natural environment,​​ aiming for near real-time​​​‌ performance. Existing methods, mainly​ in satellite observation field,​‌ rely on restrictive physical​​ assumptions unsuitable for ground-based​​​‌ application context (Structures and​ Infrastructures monitoring). Other generic​‌ methods are nonetheless computationally​​ intensive, making them impractical​​​‌ for real-time use. Our​ objective is to provide​‌ a method with effective​​ realtime calculation performance while​​​‌ still giving results comparable​ to those reference methods​‌ under the same hypotheses,​​ finally achieving both good​​​‌ accuracy and performance. The​ proposed method is based​‌ on a dynamical state-space​​ modeling for the temperature,​​​‌ where the state vector​ is assumed to be​‌ split into a dynamic​​ component for the temperature​​​‌ and a stationary component​ representing the emissivity. Then​‌ the dynamical component is​​ estimated by a Kalman​​​‌ filter approach, whereas the​ parameterized model and the​‌ emissivity component are estimated​​ through a particle filtering​​​‌ framework resulting in a​ bank of Kalman filters,​‌ also called marginalized particle​​ filter. A spatial assumption​​ of homogeneity for the​​​‌ temperature yields to the‌ addition of a Kriging‌​‌ step to the Marginalized​​ Particle Filter to overcome​​​‌ the ill-posed nature of‌ the problem and to‌​‌ compute the necessary physical​​ estimates in a reasonable​​​‌ amount of time while‌ providing fair results compared‌​‌ to reference methods from​​ the literature. A comparison​​​‌ with two state-of-the-art methods,‌ MCMC and CMA-ES, is‌​‌ presented. The results indicate​​ that the proposed method​​​‌ estimates the true value‌ within a maximum deviation‌​‌ of 3K, similar to​​ CMA-ES, while MCMC achieves​​​‌ a more accurate estimate‌ with a maximum deviation‌​‌ of 0.5K. How- ever,​​ the computational efficiency of​​​‌ the proposed method is‌ significantly improved, reducing the‌​‌ processing time by seven​​ orders of magnitude com-​​​‌ pared to MCMC and‌ three orders of magnitude‌​‌ compared to CMA-ES. This​​ remarkable efficiency highlights the​​​‌ method’s feasibility for real-time‌ monitoring of temperature and‌​‌ emissivity. 35

7.3.3 Subspace-based​​ wavenumber identification in periodic​​​‌ waveguides adapted to full-field‌ vibration measurements

Participants: Alvaro‌​‌ Gavilán Rojas, Qinghua​​ Zhang, Christophe Droz​​​‌.

Identifying wave propagation‌ properties in periodic media,‌​‌ such as composite or​​ architected materials, is critical​​​‌ for characterizing complex structures‌ experimentally. Subspace identification algorithms‌​‌ are commonly applied to​​ Operational Modal Analysis (OMA)​​​‌ data in the time‌ domain; here, the focus‌​‌ is on frequency-domain data​​ collected from successive periodic​​​‌ unit cells in 1D-periodic‌ waveguides. Instead of estimating‌​‌ modal parameters like natural​​ frequencies, the aim is​​​‌ to determine the real‌ and imaginary parts of‌​‌ the structural wavenumber, related​​ to wavelength and spatial​​​‌ decay, as well as‌ Bloch wave modes, which‌​‌ describe physical wave propagation​​ such as torsion and​​​‌ compression. Recent advances in‌ full-field vibration measurement techniques‌​‌ provide multiple measurement points​​ per unit cell, allowing​​​‌ statistical mitigation of the‌ limitations due to a‌​‌ small number of unit​​ cells. This study proposes​​​‌ a subspace identification framework‌ that leverages these dense‌​‌ measurements for improved wavenumber​​ estimation. The approach is​​​‌ illustrated both through numerical‌ simulations of a periodic‌​‌ beam and via experimental​​ validation using optical deflectometry​​​‌ on periodic structures. By‌ constructing a state-space representation‌​‌ derived from a wave-based​​ finite element model, the​​​‌ method enhances the accuracy‌ of wavenumber identification within‌​‌ each unit cell, offering​​ a practical tool for​​​‌ characterizing periodic or architected‌ materials. 46, 58‌​‌

7.3.4 Subspace System Identification​​ with Unknown Disturbance Rejection​​​‌

Participants: Qinghua Zhang.‌

System identification usually assumes‌​‌ that the considered system​​ is driven by known​​​‌ inputs and/or stationary random‌ noises. This work considers‌​‌ the case involving unknown​​ inputs, which are arbitrary​​​‌ disturbances. A typical example‌ is a mechanical structure‌​‌ naturally excited by wind,​​ which changes direction from​​​‌ time to time. To‌ address such disturbances, subspace‌​‌ methods for system identification​​ will incorporate techniques of​​​‌ unknown input observers, which‌ are state estimators with‌​‌ the ability to reject​​ arbitrary unknown disturbances, provided​​​‌ a mathematical model of‌ the system under consideration‌​‌ is available. Simulation results​​ are reported to illustrate​​​‌ the proposed method for‌ system identification while rejecting‌​‌ unknown disturbances. 57

7.4​​​‌ Joint data/model analysis

7.4.1​ Physics-Informed Neural Networks for​‌ Structural Health Monitoring

Participants:​​ Nikhil Mahar, Laurent​​​‌ Mevel.

Structural Health​ Monitoring (SHM) is crucial​‌ for ensuring the safety​​ and durability of engineering​​​‌ structures. Physics-Informed Neural Networks​ (PINNs) provide a promising​‌ approach by combining data-driven​​ models with physical knowledge,​​​‌ bridging the gap between​ purely model-based and purely​‌ data-driven methods. The works​​ presented here explore complementary​​​‌ PINN-based strategies for SHM,​ focusing on inverse estimation,​‌ scalability, and robustness to​​ unknown inputs.

An attention-augmented​​​‌ Long Short-Term Memory network​ (Pi-Attn-LSTM) is introduced for​‌ inverse parameter estimation without​​ requiring complete state measurements.​​​‌ By integrating a temporal​ attention mechanism in an​‌ encoder-decoder setup, the network​​ adaptively focuses on critical​​​‌ features in sequential data,​ improving accuracy in dynamic​‌ environments. Validation on multi-degree-of-freedom​​ numerical simulations and a​​​‌ scaled aluminium frame demonstrates​ faster convergence and superior​‌ robustness compared to a​​ conventional Pi-LSTM, enabling reliable​​​‌ identification of localized structural​ degradation. 27

A parallel​‌ PINN framework addresses computational​​ efficiency and scalability by​​​‌ decomposing high-dimensional structural systems​ into coupled lower-dimensional subproblems,​‌ one per degree of​​ freedom, while maintaining global​​​‌ consistency through shared matrices.​ This approach supports efficient​‌ state and parameter estimation​​ for both linear and​​​‌ nonlinear systems under harmonic​ and real earthquake excitations.​‌ Experimental validation on a​​ scaled shear frame confirms​​​‌ robustness under sparse data,​ high noise, and varying​‌ system complexity. 26

An​​ input-robust LSTM (rPi-LSTM) integrates​​​‌ an output-injection strategy with​ physics-informed modeling to estimate​‌ both system states and​​ spatial health parameters in​​​‌ the presence of unknown​ or unmeasured input forces,​‌ such as wind or​​ variable loads. By preserving​​​‌ temporal dependencies while complying​ with system physics, the​‌ framework demonstrates strong robustness​​ to unknown inputs, noise,​​​‌ and data sparsity. Validation​ on numerical simulations and​‌ laboratory-scale experiments highlights its​​ practical potential for real-world​​​‌ SHM applications. 28

A​ complementary approach combines Stochastic​‌ System Identification (SSI) with​​ Physics-Informed Neural Networks (SSI-Pi-LSTM)​​​‌ for joint input-state-parameter estimation.​ SSI uses statistical and​‌ subspace-based techniques to estimate​​ state-space matrices and dominant​​​‌ modal parameters from structural​ response data. Incorporating these​‌ parameters into the PINN​​ framework reduces computation time​​​‌ and improves accuracy, enabling​ efficient and robust parameter​‌ identification for complex structural​​ systems. 49

7.4.2 Mitigating​​​‌ high dimensionality in damage​ identification for plate-like structures​‌ through substructuring with interacting​​ filtering-based approaches

Participants: Shereena​​​‌ OA, Laurent Mevel​.

High-dimensional plate-like structures,​‌ such as aircraft wings,​​ building floors, or wind​​​‌ turbine blades, require early​ detection of damage to​‌ prevent sudden catastrophic failures.​​ Traditional structural health monitoring​​​‌ methods rely on dense​ instrumentation and high-dimensional support​‌ models parameterized with damage​​ attributes, which can be​​​‌ computationally expensive and costly​ to implement. This work​‌ introduces a substructuring approach​​ combined with a robust​​​‌ Interacting Particle Kalman filter​ (IPEnKF) framework, enabling health​‌ estimation on manageable subdomains​​ independently of the rest​​​‌ of the structure. The​ process model incorporates output​‌ injection to achieve robustness​​ against unknown boundary forces​​​‌ on the substructures, while​ stage-wise monitoring reduces the​‌ required sensor coverage. Validation​​ was performed through numerical​​ simulations and experiments on​​​‌ a scaled trapezoidal Mindlin‌ plate representing the NASA‌​‌ CRM wing. The subdomain​​ approach reduced sensor requirements​​​‌ by 60% while maintaining‌ 95% accuracy in damage‌​‌ detection and assessment. Computational​​ costs were also significantly​​​‌ lowered, as each substructure‌ is monitored independently. The‌​‌ method demonstrated high reliability​​ with minimal false alarms,​​​‌ highlighting both the robustness‌ of the IPEnKF algorithm‌​‌ and the critical role​​ of strategic sensor placement​​​‌ in effective damage identification.‌ 32

7.4.3 Bayesian Filtering‌​‌ Approaches for SHM with​​ Sparse Instrumentation exploiting time-lagged​​​‌ measurements

Participants: Shereena OA‌, Laurent Mevel.‌​‌

Model-based strategies for Structural​​ Health Monitoring (SHM) often​​​‌ rely on comprehensive system‌ models and extensive instrumentation,‌​‌ which can be computationally​​ and financially demanding. Bayesian​​​‌ filtering techniques provide a‌ framework for estimating unobserved‌​‌ structural states and health​​ parameters from available measurements.​​​‌ However, sparse instrumentation can‌ limit observability, potentially leading‌​‌ to unrealistic or non-physical​​ estimates.

To address this​​​‌ challenge, a time-lagged virtual‌ sensor approach is introduced,‌​‌ leveraging delay-embedded measurement models​​ based on Taken’s theorem.​​​‌ By constructing virtual sensors‌ from time-delayed measurements, the‌​‌ dimensionality of the measurement​​ vector is enhanced, improving​​​‌ state observability. This method‌ is integrated within a‌​‌ Bayesian filtering framework using​​ an interacting particle-Kalman filter​​​‌ (IPKF), termed VS-IPKF. Unlike‌ conventional spatial virtual sensors,‌​‌ which rely on model-based​​ predictions at unmeasured locations,​​​‌ this approach uses actual‌ measurements to generate virtual‌​‌ data, improving fidelity and​​ reliability. Numerical validation on​​​‌ cantilever beam models and‌ experimental tests demonstrate significant‌​‌ improvements in state and​​ joint state-parameter estimation, especially​​​‌ under sparse instrumentation conditions.‌ 33

Building on this‌​‌ concept, the measurement model​​ is further enhanced for​​​‌ accurate mode shape reconstruction‌ by embedding time-lagged measurement‌​‌ layers. The Interacting Particle​​ Kalman Filter (IPKF) updates​​​‌ the model in the‌ time domain, allowing for‌​‌ refined system matrices and​​ more precise mode shapes.​​​‌ This method addresses challenges‌ such as non-collocated or‌​‌ insufficient instrumentation, data loss,​​ and dependence on Finite​​​‌ Element Method-based expansions. Numerical‌ experiments on a simply‌​‌ supported beam under ambient​​ vibration highlight the method’s​​​‌ improved accuracy and computational‌ efficiency compared to traditional‌​‌ approaches. 56

Extending these​​ ideas, a novel lagged​​​‌ estimation framework in the‌ modal domain combines time-lagged‌​‌ embeddings with reduced-order modeling​​ for computational efficiency. Structural​​​‌ dynamics are characterized by‌ mode shapes and natural‌​‌ frequencies modulated with location-specific​​ health variables, forming a​​​‌ simplified state-space model. Integrated‌ into a Bayesian filtering‌​‌ framework, this approach achieves​​ precise state estimation even​​​‌ for sparsely monitored or‌ complex time-varying systems. Observability‌​‌ analysis informs sensor allocation,​​ and tests on linear​​​‌ time-invariant systems show that‌ the method reduces sensor‌​‌ requirements while maintaining accuracy,​​ demonstrating its potential for​​​‌ advanced SHM and parameter‌ estimation. 53

7.4.4 Identification‌​‌ and monitoring of stochastic​​ linear subsystems with unknown​​​‌ local nonlinearities via output‌ injection

Participants: Neha Aswal‌​‌, Adrien Mélot,​​ Laurent Mevel, Qinghua​​​‌ Zhang.

Most civil‌ and mechanical structures exhibit‌​‌ nonlinear stochastic behaviour, which​​ is difficult to model​​​‌ accurately, but necessary for‌ conventional model-based structural health‌​‌ monitoring techniques. Although various​​​‌ methods have been developed​ to estimate nonlinear systems,​‌ they require information about​​ the external excitation and​​​‌ are susceptible to sensor​ noise and modelling inaccuracies.​‌ This knowledge is challenging​​ to acquire in practice.​​​‌ Hence, this work presents​ a novel nonlinearity model-agnostic​‌ approach to detect damage​​ in mechanical systems with​​​‌ localized nonlinearities. The proposed​ method utilises output injection​‌ to reject the unknown​​ nonlinearities as if they​​​‌ were unknown disturbances. By​ applying an existing disturbance​‌ rejection technique, the need​​ for a priori knowledge​​​‌ about the functional form​ of nonlinearities is avoided.​‌ Besides, a switching strategy​​ is employed to determine​​​‌ the most probable location​ of the nonlinearities, thereby​‌ eliminating the need for​​ a priori knowledge about​​​‌ their location. The method​ makes use of interacting​‌ particle Kalman filter, where​​ the particle filter estimates​​​‌ the parameters (health indices)​ in order to detect​‌ possible damage while the​​ Kalman filter simultaneously estimates​​​‌ the states. The efficiency​ of the proposed method​‌ is demonstrated with the​​ help of numerical experiments​​​‌ on a spring-mass-damper oscillator​ chain with attached localized​‌ nonlinearity. The proposed approach​​ is further validated against​​​‌ experimental data of jointed​ beams. 19

7.4.5 Damage​‌ detection and localization method​​ for wind turbine rotor​​​‌ based on Operational Modal​ Analysis and anisotropy tracking​‌

Participants: Ambroise Cadoret,​​ Laurent Mevel.

Subspace-based​​​‌ damage detection methods are​ widely used for civil​‌ engineering structures modeled as​​ linear time-invariant systems. For​​​‌ operating wind turbines modeled​ as linear time-periodic systems,​‌ these methods cannot be​​ theoretically used, due to​​​‌ the inherent assumptions associated​ with these methods in​‌ the context of linear​​ time-invariant systems. Based on​​​‌ a model approximation of​ time-periodic systems as time-invariant​‌ ones, these methods can​​ still be applied and​​​‌ adapted to perform change​ detection for time-periodic systems,​‌ through a Gaussian residual​​ built upon damage sensitive​​​‌ parameters coming from the​ identified modal parameters. The​‌ proposed method is tested​​ and validated on data​​​‌ simulated with an aero-servo-elastic​ model of an operating​‌ wind turbine, with the​​ detection of local stiffness​​​‌ reductions on a blade​ and the localization of​‌ the damaged blade. Furthermore,​​ two selections of sensors​​​‌ are tested, to evaluate​ the impact of the​‌ sensor choice on the​​ performance of the detection​​​‌ and localization methods. 20​

7.4.6 Model Updating of​‌ Rotating Wind Turbines Using​​ Operational Modal Analysis and​​​‌ Floquet Mode Decomposition

Participants:​ Nina Delette, Laurent​‌ Mevel.

The structural​​ complexity of modern wind​​​‌ turbines, combined with numerous​ uncertain or unknown parameters,​‌ presents significant challenges for​​ accurate predictive modeling. Model​​​‌ updating, which refines numerical​ model parameters using measurement​‌ data, offers a means​​ to mitigate these discrepancies.​​​‌ While extensively applied to​ stationary structures, its extension​‌ to rotating wind turbines​​ remains limited, as their​​​‌ time-periodic dynamics violate key​ assumptions underlying conventional methods.​‌ This study develops a​​ numerical framework for model​​​‌ updating of rotating wind​ turbines based on an​‌ equivalent Linear Time-Invariant (LTI)​​ approximation, derived through a​​​‌ Fourier decomposition of the​ system’s Floquet modes. A​‌ simplified 5 Degrees of​​ Freedom (DoF) turbine model​​ is employed to evaluate​​​‌ the effectiveness of a‌ deterministic model updating strategy‌​‌ leveraging this approximation. Synthetic​​ vibration data, generated from​​​‌ the model using a‌ predefined parameter set, serve‌​‌ as reference measurements for​​ assessing parameter recovery accuracy.​​​‌ Modal features extracted via‌ Operational Modal Analysis (OMA)‌​‌ are used to construct​​ the cost function that​​​‌ quantifies discrepancies between predicted‌ and observed modes. The‌​‌ results underscore the potential​​ of equivalent LTI representations​​​‌ in facilitating model updating‌ for rotating systems, as‌​‌ they effectively capture the​​ modal characteristics identified via​​​‌ OMA. This study establishes‌ a foundation for extending‌​‌ this methodology to more​​ complex, industrial-scale wind turbine​​​‌ models, provided that the‌ computational cost of model‌​‌ evaluation remains manageable. 39​​, 40

7.4.7 An​​​‌ indirect data-driven model-updating framework‌ to estimate soil–pile interaction‌​‌ parameters using output-only data​​

Participants: Michael Doehler.​​​‌

A data-driven model updating‌ framework is developed to‌​‌ estimate the operational parameters​​ of a laterally-impacted pile.​​​‌ The goal is to‌ facilitate the estimation of‌​‌ soil-pile interaction parameters such​​ as the mobilized mass​​​‌ and stiffness, as well‌ as geometrical data such‌​‌ as embedded pile length,​​ using output-only information. Accurate​​​‌ knowledge of mass, stiffness,‌ and pile embedded length‌​‌ is essential for understanding​​ foundation behavior when developing​​​‌ digital-twin models of structures‌ for the purpose of‌​‌ damage detection. The method​​ first employs subspace identification​​​‌ to determine modal parameters‌ and quantifies their uncertainties‌​‌ using output-only data. The​​ covariance matrix adaptation evolution​​​‌ strategy (CMA-ES), a stochastic‌ evolutionary algorithm, is subsequently‌​‌ used to update the​​ model. The effectiveness of​​​‌ the approach is demonstrated‌ through its application to‌​‌ numerical models in this​​ work, to quantify errors,​​​‌ and subsequently to data‌ from a documented full-scale‌​‌ field test of a​​ pile subjected to an​​​‌ impact load. The work‌ underscores the potential of‌​‌ statistical updating in advancing​​ the accuracy and reliability​​​‌ of soil-structure interaction parameter‌ estimation for systems where‌​‌ only output data might​​ exist. 23

7.4.8 Subspace-Based​​​‌ Noise Covariance Estimation for‌ Bayesian Filters in SHM‌​‌

Participants: Michael Doehler,​​ Neha Aswal, Laurent​​​‌ Mevel, Qinghua Zhang‌.

The performance of‌​‌ Kalman and Bayesian filters​​ in state and parameter​​​‌ estimation critically depends on‌ accurate knowledge of process‌​‌ and measurement noise covariances.​​ In practice, these covariances​​​‌ are often unknown and‌ heuristically tuned, which can‌​‌ be cumbersome and may​​ not yield optimal results.​​​‌ Optimization-based or matrix inversion‌ methods exist but are‌​‌ computationally demanding and potentially​​ numerically unstable.

A subspace-based​​​‌ identification approach provides an‌ efficient method to estimate‌​‌ the covariance of potentially​​ correlated process and measurement​​​‌ noises, particularly in virtual‌ sensing applications. Virtual sensors‌​‌ are used to reconstruct​​ system responses at unmeasured​​​‌ locations, enabling the monitoring‌ of structural states where‌​‌ physical instrumentation is limited.​​ The subspace-based method outperforms​​​‌ traditional autocovariance least-squares schemes‌ and provides reliable initial‌​‌ covariance estimates even in​​ the presence of model​​​‌ errors. Laboratory experiments demonstrate‌ that predictions at sensor‌​‌ locations not used in​​ the identification procedure closely​​​‌ match actual measurements, validating‌ both the covariance estimation‌​‌ and the virtual sensing​​​‌ framework.

Integrating the estimated​ covariances into Bayesian filtering​‌ strategies enhances structural health​​ monitoring (SHM) performance. Comparative​​​‌ studies show that using​ subspace-based covariance estimates improves​‌ the accuracy and efficiency​​ of state and damage​​​‌ estimation under conditions of​ sensor noise, modeling errors,​‌ and unmeasured inputs, highlighting​​ the value of combining​​​‌ virtual sensing with robust​ noise covariance identification. 22​‌, 37

8 Bilateral​​ contracts and grants with​​​‌ industry

8.1 Bilateral contracts​ with industry

SNCF: Hot​‌ boxes detection

Participants: Jean​​ Dumoulin, Thibaud Toullier​​​‌, Boualem Merainani.​

The main strategic issue​‌ is the maintenance in​​ operational condition of the​​​‌ Hot Box Detectors (DBC).​ The removal of the​‌ DBC from the track​​ is part of Tech4Rail's​​​‌ ambition: reducing equipment to​ the track. The innovation​‌ aimed at in this​​ project is to study​​​‌ and develop a measurement​ solution to be deployed​‌ at the edge of​​ a lane out of​​​‌ danger zone and independent​ of track equipment. Among​‌ the scientific obstacles identified​​ are the following three:​​​‌

  • the behavior of the​ measurement system in deteriorated​‌ meteorological conditions in a​​ real site,
  • the design​​​‌ and implementation of an​ automated prototype for in-situ​‌ deployment (connection to an​​ existing announcement system, hardware​​​‌ packaging of the system,​ study and design of​‌ a scalable software solution​​ allowing pre-processing data),
  • the​​​‌ development of automatic processing​ tools for the analysis​‌ of massive data generated​​ by in-situ measurement systems.​​​‌
Siemens: Proof of concept​ monitoring coupled with prediction​‌ model for de-icing metro​​ lane surface

Participants: Jean​​​‌ Dumoulin, Thibaud Toullier​, Mathias Malandain.​‌

A proof of concept​​ study aims at combining​​​‌ real site monitoring solutions​ with adjoint state FE​‌ thermal model approach to​​ predict optimal heating required​​​‌ to preserve surface from​ icing in winter conditions.​‌ Furthermore, we introduced in​​ our prediction model connection​​​‌ with in-line weather forecast​ provided by Meteo France​‌ Geoservice at different time​​ horizons and spatial scales.​​​‌ Total amount: 124 k€.​

CETIM: fiber optic monitoring​‌

Participants: Xavier Chapeleau.​​

CETIM is conducting fatigue​​​‌ testing on a tank​ until it bursts, using​‌ existing fiber optic sensors​​ based on Bragg gratings​​​‌ for deformation measurement points.​ This expertise project aims​‌ to enhance this setup​​ with additional fiber optic​​​‌ sensors for distributed deformation​ measurements in a testing​‌ campaign, with the goal​​ to compare the effectiveness​​​‌ of these two monitoring​ technologies. Total amount: 20k€,​‌ until 2025.

Hottinger Brüel​​ & Kjær (HBK): uncertainty​​​‌ quantification for frequency-domain modal​ analysis

Participants: Michael Doehler​‌, Mikkel Steffensen.​​

In the context of​​​‌ the PhD of Mikkel​ Steffensen (DTU Denmark /​‌ HBK), a research collaboration​​ with HBK has started​​​‌ on developping methods for​ uncertainty quantification for input/output​‌ frequency-domain modal analysis. Mikkel​​ has spent one month​​​‌ at Inria in 2024​ for joint work on​‌ the subject. The developed​​ codes have been transferred​​​‌ to HBK's equipment software​ in 2025.

9 Partnerships​‌ and cooperations

9.1 International​​ initiatives

9.1.1 Inria associate​​​‌ team not involved in​ an IIL or an​‌ international program

PhyNET
  • Title:​​
    Integrating eigenspace and physical​​ space information via PINN​​​‌ architecture towards stochastic distance-based‌ damage detection
  • Duration:
    2024‌​‌ -> pres.
  • Coordinator:
    Subhamoy​​ Sen
  • Partners:
    • IIT Mandi​​​‌ (India)
  • Inria contact:
    Laurent‌ Mevel
  • Summary:
    Structural Health‌​‌ Monitoring (SHM) is an​​ essential process that involves​​​‌ real-time monitoring of the‌ physical condition of a‌​‌ mechanical structure in the​​ presence of environmental variations.​​​‌ This monitoring relies on‌ data collection through sensors‌​‌ and the utilization of​​ reference models that describe​​​‌ the structure in its‌ initial state. This coupling‌​‌ between sensors and numerical​​ models proves to be​​​‌ extremely challenging, primarily due‌ to the significant disparity‌​‌ between the limited number​​ of available sensors and​​​‌ the high complexity and‌ dimensionality of the models‌​‌ required for accurate monitoring.​​ The fondamental objective of​​​‌ this research project is‌ to improve state-of-the-art SHM‌​‌ strategies coupling experimental data​​ with numerical modelling by​​​‌ combining them with physics-informed‌ neural networks (PINNs). The‌​‌ numerical model should assist​​ the PINN in enhancing​​​‌ limited real-world data with‌ model-generated, damage-sensitive physical features.‌​‌ This integration aims at​​ generalizing SHM methods while​​​‌ making them adaptable to‌ various dynamic conditions and‌​‌ improve their robustness to​​ noise, sensor defects, and​​​‌ model errors.

9.1.2 Participation‌ in other International Programs‌​‌

Collaboration with Imperial College​​ London

Participants: Adrien Melot​​​‌.

A. Melot collaborates‌ with Imperial College London‌​‌ on the topic of​​ structural optimisation and identification​​​‌ for nonlinear vibrations.

Collaboration‌ with IIT Mandi

Participants:‌​‌ Laurent Mevel, Christophe​​ Droz, Adrien Melot​​​‌.

L. Mevel has‌ been directing the thesis‌​‌ of Neha Aswal (defense​​ 10/2023) with S. Sen​​​‌ at IIT Mandi, who‌ has joint the I4S‌​‌ team as a postdoc​​ with the BIENVENUE program​​​‌ (12/2023-11/2025). L. Mevel is‌ co-directing PhD candidate Nikhil‌​‌ Mahar at IIT Mandi​​ since 09/2023. Shereena OA​​​‌ and Nikhil Maher from‌ IIT Mandi have visited‌​‌ the I4S team in​​ May 2025, and Sheerena​​​‌ OA has made another‌ visit in October 2025.‌​‌

Collaboration with Université de​​ Sherbrooke

Participants: Christophe Droz​​​‌, Qinghua Zhang.‌

C. Droz and Q.‌​‌ Zhang are directing the​​ thesis of Alvaro Gavilan-Rojas​​​‌ with O. Robin at‌ Université de Sherbrooke. The‌​‌ subject is the propagation​​ of guided waves in​​​‌ periodic structures.

9.2 International‌ research visitors

9.2.1 Visits‌​‌ of international scientists

Other​​ international visits to the​​​‌ team
Shereena OA
  • Status:‌
    Postdoc
  • Institution of origin:‌​‌
    IIT Mandi
  • Country:
    India​​
  • Dates:
    04/05–24/05/2025; 02/11–16/11/2025
  • Context​​​‌ of the visit:
    associated‌ team PhyNet
  • Mobility program/type‌​‌ of mobility:
    Inria Associated​​ Team; mobility grant of​​​‌ French Institute in India‌
Nikhil Mahar
  • Status:
    PhD‌​‌ student
  • Institution of origin:​​
    IIT Mandi
  • Country:
    India​​​‌
  • Dates:
    04/05–24/05/2025
  • Context of‌ the visit:
    associated team‌​‌ PhyNet
  • Mobility program/type of​​ mobility:
    Inria Associated Team​​​‌
Lisa Schwegmann
  • Status:
    PhD‌ student
  • Institution of origin:‌​‌
    University of Rostock
  • Country:​​
    Germany
  • Dates:
    18/08–03/10/2025
  • Context​​​‌ of the visit:
    collaboration‌ on vibration-based damage loclaization‌​‌ with Michael Doehler
  • Mobility​​ program/type of mobility:
    research​​​‌ stay funded by University‌ of Rostock
Martina Vitali‌​‌
  • Status:
    PhD student
  • Institution​​ of origin:
    Politecnico Milano​​​‌
  • Country:
    Italy
  • Dates:
    01/03–31/08/2025‌
  • Context of the visit:‌​‌
    vibration-based damage analysis of​​​‌ bridges
  • Mobility program/type of​ mobility:
    research stay Italian​‌ PhD program
W.K. Chiu​​
  • Status:
    Professor
  • Institution of​​​‌ origin:
    Monash University
  • Country:​
    Australia
  • Dates:
    07/07/2025
  • Context​‌ of the visit:
    Scientific​​ visit with Vincent Le​​​‌ Cam around SHM topic​
  • Mobility program/type of mobility:​‌

9.2.2 Visits to international​​ teams

Research stays abroad​​​‌
Michael Doehler
  • Visited institution:​
    Aalborg University, Learning and​‌ Decisions Lab
  • Country:
    Denmark​​
  • Dates:
    06/02–13/02/2025
  • Context of​​​‌ the visit:
    collaboration on​ uncertainty quantification, invited seminar​‌
  • Mobility program/type of mobility:​​
    research stay
Romain Noel​​​‌
  • Visited institution:
    Université Jan​ Evangelista Purkyně, chemistry department​‌
  • Country:
    Czech Republic
  • Dates:​​
    20/10–24/10/2025
  • Context of the​​​‌ visit:
    collaboration on computational​ fluid dynamic, invited seminar​‌
  • Mobility program/type of mobility:​​
    Hubert Curien Partnerships (PHC)​​​‌ Barrande

9.3 European initiatives​

9.3.1 Horizon Europe

BRIGHTER​‌

BRIGHTER project on cordis.europa.eu​​

  • Title:
    Breakthrough in micro-bolometer​​​‌ imaging
  • Duration:
    From December​ 1, 2022 to November​‌ 30, 2026
  • Partners:
    • INSTITUT​​ NATIONAL DE RECHERCHE EN​​​‌ INFORMATIQUE ET AUTOMATIQUE (INRIA),​ France
    • MER MEC FRANCE​‌ (INNOTECH), France
    • XENICS NV​​ (XENICS), Belgium
    • SENSIA SOLUTIONS​​​‌ SL (SENSIA), Spain
    • MACQ​ SA (MACQ), Belgium
    • COMMISSARIAT​‌ A L ENERGIE ATOMIQUE​​ ET AUX ENERGIES ALTERNATIVES​​​‌ (CEA), France
    • CHAUVIN ARNOUX,​ France
    • BIGTRI BILISIM ANONIM​‌ SIRKETI, Türkiye
    • ARCELIK A.S.​​ (ARCELIK), Türkiye
    • LYNRED (LYNRED),​​​‌ France
    • UNIVERSITE GUSTAVE EIFFEL,​ France
    • CENTRE NATIONAL DE​‌ LA RECHERCHE SCIENTIFIQUE CNRS​​ (CNRS), France
    • THIMONNIER SAS,​​​‌ France
    • DOCAPESCA - PORTOS​ E LOTAS SA, Portugal​‌
    • MARMARA UNIVERSITY (MarUn), Türkiye​​
    • INOV INSTITUTO DE ENGENHARIA​​​‌ DE SISTEMAS E COMPUTADORES​ INOVACAO (INOV), Portugal
  • Inria​‌ contact:
    Laurent Mevel
  • Coordinator:​​
    LYNRED, Xavier Lucquiault
  • Summary:​​​‌

    Micro-bolometer sensors are compact,​ light, low power, reliable​‌ and affordable infrared imaging​​ components. They are ahead​​​‌ of the cooled infrared​ sensors for these criteria​‌ but lag behind them​​ in terms of performance:​​​‌

    - Existing micro-bolometer technologies​ have thermal time constants​‌ around 10 msec. This​​ is more than 10​​​‌ times that of cooled​ detectors.

    - Moreover, there​‌ is no multispectral micro-bolometer​​ sensor available today for​​​‌ applications such as absolute​ thermography and optical gas​‌ imaging.

    BRIGHTER will develop​​ 2 new classes of​​​‌ micro-bolometer solutions to reduce​ the performance gap with​‌ their cooled counterparts:

    -​​ Fast thermal micro-bolometer imaging​​​‌ solutions with time constant​ in the 2.5 to​‌ 5 msec range, that​​ is to say 2​​​‌ to 4 times faster​ than that of today’s​‌ micro-bolometer technologies. Read out​​ integrated circuits able to​​​‌ operate up to 500​ frames per seconds will​‌ also be investigated.

    -​​ Multi-spectral micro-bolometer solutions with​​​‌ at least access at​ the pixel level to​‌ 2 different wavelengths in​​ the range 7 to​​​‌ 12 µm.

    The developments​ will focus on pixel​‌ technology, Read Out Integrated​​ Circuit, low power edge​​​‌ image signal processing electronic,​ optics, and image treatment​‌ algorithms. All stakeholders of​​ the value chain are​​​‌ involved: academics, RTO, micro-bolometer​ manufacturer, algorithm developers, camera​‌ integrators and end users.​​ They will collaborate to​​​‌ define the best trade-offs​ for all use-cases.

    The​‌ 2 new classes of​​ products that will spring​​​‌ from BRIGHTER will generate​ concrete benefits. They will​‌ make it possible to​​ save on material and​​ energy in the manufacturing​​​‌ sector, perform efficient and‌ affordable monitoring of infrastructures‌​‌ and trains, contribute to​​ autonomous vehicles sensor suite,​​​‌ decrease the road casualties‌ among Vulnerable Road Users,‌​‌ better control gas emission​​ in cities and industrial​​​‌ areas. These new usages‌ served by the European‌​‌ industry will allow Europe​​ to increase its market​​​‌ share in the infrared‌ imaging industry.

USES2

Participants:‌​‌ Vincent Le Cam,​​ Romain Noel.

USES2​​​‌ project on cordis.europa.eu

  • Title:‌
    USES of novel Ultrasonic‌​‌ and Seismic Embedded Sensors​​ for the non-destructive evaluation​​​‌ and structural health monitoring‌ of critical infrastructure and‌​‌ human-built objects
  • Duration:
    2023–2027​​
  • Partners:
    • UGE
    • Universidad Politécnica​​​‌ de Madrid (UPM)
    • COMMISSARIAT‌ A L ENERGIE ATOMIQUE‌​‌ ET AUX ENERGIES ALTERNATIVES​​ (CEA)
    • FRAUNHOFER GESELLSCHAFT ZUR​​​‌ FORDERUNG DER ANGEWANDTEN FORSCHUNG‌ EV (IZFP)
    • BUNDESANSTALT FUER‌​‌ MATERIALFORSCHUNG UND -PRUEFUNG (BAM)​​
    • ISAMGEO ITALIA S.R.L. (Isamgeo)​​​‌
    • UNIVERSITE LIBRE DE BRUXELLES‌ (ULB)
    • AIRBUS DEFENCE AND‌​‌ SPACE SA (AIRBUS)
    • ZENSOR​​ (Zensor)
    • UNIVERSITY OF BRISTOL​​​‌ (UBRI)
  • Inria contact:
    Vincent‌ Le Cam
  • Coordinator:
    Université‌​‌ Gustave Eiffel, Odile Abraham​​
  • Summary:
    Infrastructure makes up​​​‌ the arteries of modern‌ society, providing people, organisations‌​‌ with all necessities –​​ from utilities to housing​​​‌ and transport. However, its‌ maintainance can be difficult.‌​‌ While non-destructive evaluation is​​ the process currently being​​​‌ used, it is disruptive‌ to infrastructure. An interesting‌​‌ possibility is to use​​ condition-based structural health monitoring​​​‌ (SHM) with sensors. However,‌ these sensors currently provide‌​‌ local information making it​​ inefficient for the size​​​‌ and complexity of infrastructure.‌ The EU-funded USES2 project‌​‌ aims to develop an​​ alternative by bringing together​​​‌ new sensor technologies, improved‌ processing tools and full-mechanical-waveform-based‌​‌ imaging, as well, as​​ training researchers to efficiently​​​‌ utilise these tools. This‌ will allow for efficient‌​‌ larger-scale infrastructure structural health​​ monitoring, essential for their​​​‌ everyday use.

9.4 National‌ initiatives

ANR PRC SWEAT-City‌​‌

Participants: Romain Noel,​​ Jean Dumoulin.

  • Duration:​​​‌ 2024 – 2028
  • Budget:‌ 409 k€
  • Title: Simulation‌​‌ of Water Evaporation within​​ Artificial ground for Thermo-regulation​​​‌ of the City
  • Abstract:‌ The global warming and‌​‌ the more extreme events​​ related implies that cities​​​‌ will be concerned by‌ Urban Heat Island (UHI)‌​‌ effect more often and​​ more intensively. Pavements cover​​​‌ between 30% and 40%‌ of city areas and‌​‌ have a strong effect​​ on the UHI. Studies​​​‌ are showing that two‌ major phenomena can be‌​‌ used and then must​​ be studied to reduce​​​‌ the effect of pavements‌ on UHI: The albedo‌​‌ and the evaporation of​​ water. The increase in​​​‌ albedo has a beneficial‌ effect on the surface‌​‌ temperature of pavements but​​ increases radiation on the​​​‌ vertical surfaces of the‌ city. The present proposal‌​‌ focuses on the effect​​ of water evaporation on​​​‌ UHI. Research on that‌ topic is increasing in‌​‌ the recent years, and​​ only few papers are​​​‌ available on the numerical‌ simulation. However, the evaporation‌​‌ of porous media is​​ a complex phenomenon by​​​‌ its geometry, its interactions‌ between the matrix and‌​‌ fluids, the phase change​​ etc. This complexity leads​​​‌ to macroscopic models with‌ numerous parameters that are‌​‌ hard to obtain experimentally​​​‌ and to optimize. The​ aim of the project​‌ is to develop a​​ heat and mass numerical​​​‌ model that considers evaporation​ in a construction material.​‌ The model is based​​ on a multiscale approach​​​‌ combining the ability of​ Lattice Bolzman Method at​‌ the pore scale and​​ Finite Element at the​​​‌ macro scale. Experiments will​ be carried out at​‌ different scales to validate​​ the modelings. Finally experiments​​​‌ in simulated real life​ situation within the Sense​‌ City facility will be​​ performed and simulated in​​​‌ order to validate the​ models.
ANR JCJC Archi-Noise​‌

Participants: Christophe Droz.​​

  • Duration: 2024 – 2028​​​‌
  • Budget: 286 k€
  • Title:​ Architected materials with meso-scale​‌ interactions for Noise and​​ vibration control
  • Abstract: Noise,​​​‌ vibration, and harshness (NVH)​ impact multiple industries, affecting​‌ health, system longevity, and​​ sustainability. Despite advances in​​​‌ NVH mitigation materials, performance​ gains are plateauing due​‌ to constraints like cost,​​ compactness, adaptability, and structural​​​‌ integrity. ArchiNoise seeks to​ redefine material design by​‌ exploring architected meta-structures at​​ meso- and macro-scales, surpassing​​​‌ traditional vibro-acoustic limits. It​ will adapt nano-scale physics​‌ and electromagnetism concepts to​​ structural engineering, creating scattering​​​‌ effects akin to Bragg​ and locally resonant bandgaps,​‌ but independent of periodic​​ unit-cell dimensions or oscillator​​​‌ mass. These novel waveguiding​ phenomena will target broadband​‌ NVH control. ArchiNoise will​​ develop theoretical, computational, and​​​‌ phenomenological tools to design​ and optimize these materials.​‌ By integrating enriched continuum​​ theories, vibroacoustics, inverse wave-based​​​‌ identification, and lattice-based periodic​ modeling, it will pioneer​‌ lightweight NVH solutions.
ANR​​ France 2030 ExcellenceS City-FAB​​​‌ / CD 92

Participants:​ Jean Dumoulin, Thibaud​‌ Toullier, Mathias Malandain​​.

  • Duration: 2024 –​​​‌ 2028
  • Partners: CD 92,​ UGE laboratories
  • Budget: 600​‌ k€, 80 k€ for​​ the team
  • Title: Analysis​​​‌ of uses, and study​ of comfort and urban​‌ atmosphere on an avenue​​ scale
  • Abstract: The objective​​​‌ is to anticipate and​ adapt road redevelopment projects​‌ by aiming at better​​ sharing of mobility spaces,​​​‌ making travel safer and​ enhancing the environment. These​‌ objectives meet the issues​​ of sustainable cities and​​​‌ territories. This project focuses​ on the environmental effects​‌ of developments, in particular​​ concerning thermal comfort, air​​​‌ quality and acoustic comfort.​ Our contribution to this​‌ project focuses on in-situ​​ monitoring and data-driven studies.​​​‌
ANR SCaNING

Participants: Vincent​ Le Cam.

  • Duration:​‌ 2021 – 2025
  • Partners:​​ UGE (Coordinator), Université de​​​‌ Toulouse, Aix-Marseille Université, Université​ de Bordeaux, Andra, EDF​‌
  • Inria contact: Vincent Le​​ Cam
  • Abstract: Using embedded​​​‌ sensors which will provide​ information similar to that​‌ used in NDE while​​ allowing to continuously evaluate​​​‌ performance indicators (compressive strength​ and Young’s modulus) and​‌ the concrete conditions (porosity​​ and water content) to​​​‌ improve indicator reliability and​ optimize diagnosis and communicating​‌ sensors through fully autonomous,​​ low-power networks makes it​​​‌ possible to consider systems​ with low installation and​‌ operation costs. The project​​ is lead by MAST​​​‌ LAMES laboratory of UGE.​ The instrumentation part is​‌ ensured by I4S.
ANR​​ Convinces

Participants: Jean Dumoulin​​​‌, Romain Noël.​

  • Duration: 11/2021 – 10/2025​‌
  • Partners: Univ. Lorraine (coordinator),​​ CERTES (UPEC), Univ. Strasbourg,​​ UGE, Cerema.
  • Abstract: The​​​‌ ANR project CONVINCES is‌ investigating the influence of‌​‌ convection in suspensions of​​ micro-encapsulated phase change material​​​‌ (mPCM) in urban civil‌ engineering applications. This project‌​‌ will include LBM (Lattice​​ Boltzmann Method) and DEM​​​‌ (Discrete Element Method) in‌ multi-scale simulations plus series‌​‌ of experiments at different​​ scales to study the​​​‌ thermal impact of such‌ mPCM suspensions in porous‌​‌ media. The final objective​​ is the thermal regulation​​​‌ of pavements.
ANR RESBIOBAT‌

Participants: Jean Dumoulin.‌​‌

  • Duration: 01/2022 – 12/2025​​
  • Partners: UGE (coordinator), CERTES​​​‌ (UPEC), LNE, CSTB, Cerema,‌ Themacs Ingénierie.
  • Abstract: The‌​‌ ANR project RESBIOBAT addresses​​ energy and environmental issues.​​​‌ Major advances are expected‌ in the building sector.‌​‌ Reliable in-situ thermal characterization​​ of buildings before and​​​‌ after a renovation action‌ are required. Moreover, construction‌​‌ must be more "sustainable",​​ notably by using bio-sourced​​​‌ materials and raw earth.‌ In this project, we‌​‌ propose an inter-disciplinary technical​​ solution combining modeling, simulations​​​‌ and measurements for a‌ better in-situ evaluation of‌​‌ the energy performances of​​ conventional and sustainable walls.​​​‌ The identification of the‌ thermal characteristics will be‌​‌ performed by an inverse​​ method combining a hygro-thermal​​​‌ model solved in real‌ time by a "reduced‌​‌ bases" technique and sensors​​ selected by "optimal experimental​​​‌ design". After a robustness‌ study via virtual tests,‌​‌ a prototype will be​​ realized and tested on​​​‌ real walls in laboratory‌ and in the Equipment‌​‌ of Excellence Sense-City.
PIA4:​​ MINERVE

Participants: Vincent Le​​​‌ Cam.

  • Duration: 2022–2027‌
  • 22 partners, coordinator: SNCF.‌​‌ Budget: 40 M€, 743​​ k€ for the team​​​‌
  • Title: Méthodes et outils‌ pour la collaboration sectorielle‌​‌ et la continuité numérique​​ sur le cycle de​​​‌ vie (MINERVE)
  • Abstract: The‌ six main objectives of‌​‌ the MINERVE project are:​​ - Develop design and​​​‌ construction methods and tools‌ using effective BIM approaches‌​‌ for each business -​​ Anticipate and optimize the​​​‌ construction phase, based on‌ sustainable BIM (digital continuity,‌​‌ frugality of models) -​​ Developing digital twins (exploring​​​‌ the potential of AI‌ for decision support), using‌​‌ opportunities with regard to​​ biodiversity and the environment​​​‌ - Use the digital‌ twin to improve resilience‌​‌ to climate change -​​ Develop an industrializable, standardized​​​‌ and shared vision of‌ interfaces ensuring digital continuity‌​‌ via the BIM model​​ on all phases -​​​‌ Build a collaborative ecosystem‌ around the modeling of‌​‌ linear and particularly railway​​ infrastructure

    The team participates​​​‌ with BIM and monitoring‌ of railway structures by‌​‌ modeling vibrations, defining original​​ ways of operational monitoring​​​‌ including fiber optic sensors.‌

PIA4: DIAM

Participants: Vincent‌​‌ Le Cam.

  • Duration:​​ 2022–2026
  • Partners: STIMIO (coordinator),​​​‌ SNIC, UGE. Budget: 3‌ M€, 693 k€ for‌​‌ the team.
  • Abstract: In​​ this project, new ways​​​‌ to diagnose infrastructure deterioration‌ are identified through the‌​‌ use of innovative instrumentation​​ and by merging different​​​‌ data sources. With focus‌ on railway monitoring, the‌​‌ goal is online diagnosis​​ communication of critical trackside​​​‌ elements, and to enrich‌ trackside elements with augmented‌​‌ infrastructure monitoring systems. New​​ algorithms and models for​​​‌ predictive maintenance are developed.‌
ANR France2030 Sci-ty Geronimo‌​‌

Participants: Vincent Le Cam​​​‌, Arthur Bouche,​ Adji Toure.

  • Duration:​‌ 10/2025-09/2027
  • Abstract: This project​​ is a maturation project​​​‌ aimed at advancing Acoustic​ Emission technologies and associated​‌ know-how to a higher​​ TRL. The objective is​​​‌ to develop off-the-shelf, fully​ synchronized wireless sensor nodes​‌ capable of running Structural​​ Health Monitoring (SHM) algorithms​​​‌ in situ and in​ real time, such as​‌ Time Difference of Arrival​​ (TDOA) algorithms.
ANR France2030​​​‌ Sci-ty OBLiX

Participants: Romain​ Noel.

  • Duration: 02/2025-01/2026​‌
  • Abstract: The OBLiX pre-maturation​​ project aims at its​​​‌ extension and development. The​ main objective is to​‌ address the real need​​ for tools enabling structural​​​‌ health monitoring (SHM) for​ sustainable, resilient, and safe​‌ cities. Currently, the field​​ lacks generic, flexible, and​​​‌ efficient solutions for connecting​ sensors to physical and​‌ mathematical models. OBLiX, stands​​ out for its ability​​​‌ to combine genericity, flexibility,​ lightweight design, and efficiency.​‌ It offers an approach​​ better suited to SHM​​​‌ and embedded electronics. OBLiX's​ innovative nature lies in​‌ its combination of functionalities​​ and its ability to​​​‌ combine highly heterogeneous models.​ Its development is part​‌ of the National Acceleration​​ Strategy for Sustainable Cities​​​‌ and Innovative Buildings, thus​ contributing to the emergence​‌ of a sustainable construction​​ culture and the creation​​​‌ of a community of​ SHM experts.
ANR France2030​‌ Sci-ty TAPAS

Participants: Thibaud​​ Toullier, Arthur Bouche​​​‌.

  • Duration: 05/2025-04/2026
  • Abstract:​ The TAPAS software (Tracking,​‌ Acquisition, Processing, Archiving &​​ Storage) addresses the growing​​​‌ needs of instrumentation projects,​ which play a key​‌ role in the development​​ of tomorrow’s smart and​​​‌ connected cities. Designed to​ manage complex projects and​‌ supervise large-scale sensor networks,​​ the development of TAPAS​​​‌ ensures the collection, storage,​ visualization, archiving, and control​‌ of the generated data.​​

    A dedicated programming interface​​​‌ enables seamless integration into​ domain-specific applications, while an​‌ intuitive user interface allows​​ users to visualize and​​​‌ manage projects as well​ as control data sharing.​‌ TAPAS therefore supports structural​​ health monitoring and energy​​​‌ optimization of infrastructures, contributing​ to more sustainable, resilient,​‌ and innovative cities.

    Finally,​​ through the integration of​​​‌ computational models, TAPAS paves​ the way for the​‌ deployment and operation of​​ digital twins dedicated to​​​‌ the real-time monitoring, control,​ and optimization of infrastructures.​‌

CETIM

Participants: Michael Doehler​​, Xavier Chapeleau.​​​‌

  • Duration: 09/2024–08/2025
  • Partners: CETIM,​ I4S, UGE/MAST-SMC. Budget: 100​‌ k€
  • Abstract: This research​​ collaboration funded by CETIM​​​‌ aims at developing a​ thesis project focused on​‌ data fusion and AI​​ using data from SHM​​​‌ sensors to create predictive​ models for fatigue damage​‌ (initiation and propagation of​​ cracks) in welded structures.​​​‌ This preliminary study focuses​ on evaluating SHM sensors​‌ and the processing and​​ fusion of data related​​​‌ to the considered use​ case.
CETIM

Participants: Michael​‌ Doehler, Christophe Droz​​.

  • Duration: 10/2025–09/2028
  • Partners:​​​‌ CETIM, I4S. Budget: 240​ k€
  • Abstract: Following the​‌ previous research collaboration with​​ CETIM, a PhD project​​​‌ has been launched within​ the strategic partnership between​‌ Inria and CETIM. The​​ PhD of Hovanes Boksyan​​​‌ on Digital twins for​ monitoring welded mechanical components​‌ is funded within CETIM's​​ Digital Twin program.
AID​​

Participants: Christophe Droz,​​​‌ Michael Doehler.

  • Duration:‌ 10/2025–09/2028
  • Partners: DGA TT,‌​‌ Université Angers, I4S.
  • Abstract:​​ This project aims to​​​‌ improve vibration analysis methods‌ used to assess the‌​‌ reliability and durability of​​ complex systems - particularly​​​‌ military vehicles and their‌ onboard equipment - under‌​‌ realistic operating conditions. Building​​ on the NF X50-144​​​‌ standard, the work seeks‌ to replace generic test‌​‌ procedures with more customized,​​ data-driven approaches using AI​​​‌ techniques to analyse vibration‌ profiles for fatigue prediction.‌​‌
CEA

Participants: Romain Noel​​.

  • Partners: CEA/DM2S/STMF.
  • Abstract:​​​‌ Within the Inria/CEA collaborative‌ framework, I4S and the‌​‌ LMSF started to work​​ together on CFD methods.​​​‌ This collaboration led to‌ a first M2 internship‌​‌ and the collaboration continues​​ through the PhD project​​​‌ of Clément Bardet (2024–2027)‌ on the use of‌​‌ thermo-chemical potential in LBM.​​
IFPEN

Participants: Laurent Mevel​​​‌.

Collaboration with IFPEN‌ leading to the thesis‌​‌ of A. Cadoret on​​ applying OMA techniques on​​​‌ wind turbines, and a‌ new PhD project has‌​‌ started with PhD candidate​​ N. Delette (2023–2026).

AEx​​​‌ - Fluidonics

Participants: Christophe‌ Droz, Romain Noel‌​‌.

  • Duration: 05/2025–10/2028
  • Abstract:​​ This project explores seismic​​​‌ barrier concepts relying on‌ fluid sloshing. The objective‌​‌ is to optimize the​​ internal flow turbulence as​​​‌ well as the tank's‌ structural design to combine‌​‌ dissipation phenomena with interference​​ of seismic waves. The​​​‌ M2 internship of Methmika‌ Athulkotte (05-10/2025) was dedicated‌​‌ to the project, and​​ PhD student Louis Ramseyer​​​‌ started in 11/2025.
ANR‌ ASTRID HYDRAVIB

Participants: Boris‌​‌ Lossouarn.

  • Duration: 09/2023–08/2026​​
  • Partners: Cnam (coordinator), Arts​​​‌ et Métiers Lille, École‌ navale
  • Title: Piezoelectric damping‌​‌ for mitigation of flow-induced​​ vibrations
  • Abstract: Unlike electromagnetic​​​‌ waves, underwater acoustic waves‌ propagate with very low‌​‌ attenuation and can be​​ measured more than a​​​‌ hundred kilometers away. Acoustic‌ noise comes from various‌​‌ sources including propeller cavitation,​​ hydroacoustic phenomena and vibration​​​‌ of structural components. The‌ HYDRAVIB project aims to‌​‌ reduce the vibration-induced noise​​ under hydrodynamic flow by​​​‌ proposing piezoelectric damping techniques‌ intended for the mitigation‌​‌ of structural resonances. These​​ techniques will also contribute​​​‌ to the increase in‌ the lifespan of the‌​‌ blades, hydrofoils or fins,​​ by reducing fatigue in​​​‌ a vibrating environment.

10‌ Dissemination

10.1 Promoting scientific‌​‌ activities

10.1.1 Scientific events:​​ organisation

General chair, scientific​​​‌ chair
  • Michael Doehler
    • General‌ chair of IOMAC 2025,‌​‌ Rennes, 20-23/05/2025
  • Jean Dumoulin​​
    • Chair of the scientific​​​‌ day on Inrared Thermography‌ for the French Society‌​‌ of Thermal Science (Paris,​​ Fiap Jean Monet, 16th​​​‌ October 2025)
Member of‌ the organizing committees
  • Vincent‌​‌ Le Cam
    • Organization of​​ SHM@COFREND day, Grenoble, 19-20/03/2025​​​‌
    • Part of the organization‌ of IWSHM at Standord,‌​‌ USA, 9-11/09/2025
    • Part of​​ the organization of the​​​‌ SHM days of Gustave‌ Eiffel University Marne la‌​‌ Vallée, France, 5-6/11/2025
  • Christophe​​ Droz , Laurent Mevel​​​‌ , Adrien Melot ,‌ Alvaro Gavilan Rojas ,‌​‌ Gunther Tessier
    • Organizing committee​​ of IOMAC 2025, Rennes,​​​‌ 20-23/05/2025
Session organization
  • Jean‌ Dumoulin
    • co-chair of session‌​‌ GI5.1 | Urban Geophysics​​ at EGU GA 2025​​​‌
  • Adrien Mélot
    • Organization and‌ co-chair of session: “S8:‌​‌ Modeling and computational methods​​​‌ for physical model-based identification”​ at IOMAC 2025
  • Christophe​‌ Droz
    • Organization and co-chair​​ of session: “S8: Modeling​​​‌ and computational methods for​ physical model-based identification” and​‌ chair of the Industrial​​ Keynotes Session at IOMAC​​​‌ 2025

10.1.2 Scientific events:​ selection

Chair of conference​‌ program committees
  • Vincent Le​​ Cam
    • head and general​​​‌ secretary of the EWSHM​ scientific committee
  • Jean Dumoulin​‌
    • vice chairman of QIRT​​ steering committee since 2024​​​‌
Member of the conference​ program committees
  • Jean Dumoulin​‌
    • member of the scientific​​ committee of the GI​​​‌ Division (Geosciences Instrumentation and​ Data Systems) of EGU​‌ (European Geosciences Union) for​​ infrastructure instrumentation and monitoring​​​‌ since 2013 and GI​ Division sub-Program Committee member​‌ since 2020
    • member of​​ the scientific committee of​​​‌ QIRT (quantitative Infrared Thermography)​ since 2014
  • Qinghua Zhang​‌
    • member of the 6th​​ International Conference on Control​​​‌ and Fault-Tolerant Systems (SysTol​ 2025) scientific committee
    • member​‌ of IFAC Technical Committee​​ on Modelling, Identification and​​​‌ Signal Processing (TC 1.1)​
    • member of IFAC Technical​‌ Committee on Adaptive and​​ Learning Systems (TC 1.2)​​​‌
    • member of IFAC Technical​ Committee on Fault Detection,​‌ Supervision and Safety of​​ Technical Processes (TC 6.4)​​​‌
  • Laurent Mevel
    • member of​ the EWSHM scientific committee​‌
    • member of the IOMAC​​ scientific committee
  • Vincent Le​​​‌ Cam
    • member of the​ IWSHM scientific committee
    • member​‌ of SHM@COFREND scientific committee​​
  • Michael Doehler
    • member of​​​‌ IFAC Technical Committee on​ Modelling, Identification, and Signal​‌ Processing (TC 1.1) since​​ 2017
    • member of the​​​‌ IOMAC scientific committee since​ 2018
    • member of the​‌ SHM@COFREND scientific committee since​​ 2021
    • member of the​​​‌ EWSHM scientific committee since​ 2022
    • member of EVACES​‌ 2025 scientific committee and​​ award committee
Reviewer
  • Michael​​​‌ Doehler was reviewer for​ EVACES 2025.
  • Jean Dumoulin​‌ was reviewer for QIRT​​ ASIA 2025, EGU 2025.​​​‌
  • Vincent Baltazart was reviewer​ for IOMAC 2025.
  • Qinghua​‌ Zhang was reviewer for​​ CDC 2025, SysTol 2025.​​​‌
  • Adrien Mélot was reviewer​ for NeurIPS AI4Science Workshop,​‌ NODYCON 2025, IFAC Symposium​​ on Robotics, IFAC Symposium​​​‌ on Mechatronic Systems, ASME​ Turbomachinery Technical Conference &​‌ Exposition, IOMAC 2025.
  • Christophe​​ Droz was reviewer for​​​‌ IOMAC 2025.
  • Romain Noel​ was reviewer for GRETSI​‌ 2025.

10.1.3 Journal

Member​​ of the editorial boards​​​‌
  • Jean Dumoulin is member​ of the editorial board​‌ of the journal Quantitative​​ Infrared Thermography, and Executive​​​‌ Editor for the journal​ Geoscientific Instrumentation, Methods and​‌ Data Systems.
  • Laurent Mevel​​ is member of the​​​‌ editorial board of the​ journal of Mechanical Systems​‌ and Signal Processing.
Reviewer​​ - reviewing activities
  • Christophe​​​‌ Droz was reviewer for​ Nonlinear Dynamics, Advances in​‌ Engineering Software, Physics of​​ Fluids, Mechanical Systems and​​​‌ Signal Processing, Journal of​ Sound and Vibration, Wave​‌ Motion, European Journal of​​ Mechanics - A/Solids.
  • Laurent​​​‌ Mevel was reviewer for​ Mechanical Systems and Signal​‌ Processing and Engineering Structures.​​
  • Michael Doehler was reviewer​​​‌ for Mechanical Systems and​ Signal Processing, Journal of​‌ Sound and Vibration, Data-Centric​​ Engineering
  • Jean Dumoulin was​​​‌ reviewer for Building and​ Environment, SPIE Optical Engineering,​‌ GI Journal (EGU), QIRT​​ Journal.
  • Romain Noel was​​​‌ reviewer for Journal Computational​ Particle Mechanics.
  • Xavier Chapeleau​‌ was reviewer for the​​ journals Journal of Civil​​ Structural Health Monitroing, Engineering​​​‌ Structures, Measurement, Sensors and‌ Actuators A Physical.
  • Vincent‌​‌ Baltazart was reviewer for​​ NDT&E, MSSP, Measurement, Applied​​​‌ Sciences, Optik, IEEE Trans.‌ Intelligent Transportation System, Engineering‌​‌ Structures, Automation in Construction.​​
  • Qinghua Zhang was reviewer​​​‌ for IEEE Transactions on‌ Automatic Control, Automatica, Mechanical‌​‌ Systems and Signal Processing.​​
  • Adrien Mélot was reviewer​​​‌ for Nonlinear Dynamics, Mechanical‌ Systems and Signal Processing,‌​‌ Journal of Sound and​​ Vibration, Communications in Nonlinear​​​‌ Science and Numerical Simulation,‌ International Journal of Dynamics‌​‌ and Control, Journal of​​ Nonlinear Mathematical Physics.
  • Boris​​​‌ Lossouarn was reviewer for‌ Mechanical Systems and Signal‌​‌ Processing and Nonlinear Dynamics.​​

10.1.4 Invited talks

  • Christophe​​​‌ Droz
    • "Modélisation des structures‌ périodiques: Applications à la‌​‌ non-localité, non-linéarité, l'identification et​​ la réduction de modèles".​​​‌ Institut Polytechnique de Paris,‌ UMA, POEMS, France, 11/12/2025.‌​‌
    • "Reduced frequency-driven Bloch Wave​​ Decomposition for Harmonic Analysis​​​‌ of Finite Periodic Structures".‌ 7th International Conference on‌​‌ Phononic Crystals/Metamaterials, Phonon Transport,​​ Topological Phononics, Seoul, Korea,​​​‌ 09/06/2025.
    • "Dynamics of Periodic‌ Structures: modeling, identification and‌​‌ applications". ISAE-Supmeca, VAST-FM, France,​​ 06/02/2025.
  • Vincent Le Cam​​​‌
    • introduction keynote on SHM‌ development in France at‌​‌ the 8th SHM@COFREND day​​ in Grenoble, 19/03/2025
  • Michael​​​‌ Doehler
    • “Statistical uncertainties and‌ change detectability in vibration-based‌​‌ structural monitoring”, invited seminar,​​ Aalborg University, Denmark, 11/02/2025​​​‌
  • Jean Dumoulin
    • “Ultra Time‌ Domain Infrared Thermography in‌​‌ ground based outdoor monitoring:​​ outcomes and perspectives”, QIRT​​​‌ ASIA 2025, HARBIN, China,‌ 14-18 July 2025.
  • Boualem‌​‌ Merainani
    • “Détection et suivi​​ de boites d’essieux par​​​‌ thermographie infrarouge ”, Journée‌ d’étude de la Société‌​‌ Française de Thermique (SFT)​​ sur la Thermographie Infrarouge,​​​‌ 16 octobre 2025, FIAP,‌ Paris.
  • Thibaud Toullier
    • “DAM2‌​‌ - A Scalable and​​ Compliant Solution for Managing​​​‌ enriched Infrared images as‌ FAIR Research Data ”,‌​‌ Journée d’étude de la​​ Société Française de Thermique​​​‌ (SFT) sur la Thermographie‌ Infrarouge, 16 octobre 2025,‌​‌ FIAP, Paris.
  • Adrien Mélot​​
    • "An Overview of Deep​​​‌ Learning Paradigms for Mechanical‌ Engineering", Lyon, France, 06/11/2025.‌​‌
  • Romain Noel
    • "The LBM​​ use for fluid dynamics​​​‌ in granular media", invited‌ seminar at Université Jan‌​‌ Evangelista Purkyně, Czech Republic,​​ 10/2025
    • "Phase change for​​​‌ thermoregulation of porous media",‌ invited talk at the‌​‌ compagny Dotblock, 11/2025, France.​​

10.1.5 Leadership within the​​​‌ scientific community

  • Vincent Le‌ Cam
    • co-chair of SHM@COFREND:‌​‌ this activity branch of​​ the COFREND (French Confederation​​​‌ for Non-destructive Testing) aims‌ at uniting the national‌​‌ SHM community from academia​​ and industry, and to​​​‌ promote and standardize the‌ SHM sector in France.‌​‌
    • member of the scientific​​ council of WEN (West​​​‌ Electronic Network) since 2014,‌ which is a cluster‌​‌ of about 200 companies,​​ academics and research laboratories​​​‌ active in electronics
  • Michael‌ Doehler
    • co-leader of the‌​‌ working group “GT SHM​​ Data” within SHM@COFREND. The​​​‌ GT focuses on scientific‌ issues, technical challenges and‌​‌ standards of the SHM​​ sector related to handling​​​‌ and processing of structural‌ monitoring data. The GT‌​‌ involves around 50 people​​ from academia and industry​​​‌ in France.

10.1.6 Scientific‌ expertise

  • Christophe Droz was‌​‌ expert evaluator for the​​ French National Research Agency​​​‌ (ANR) and for the‌ Campus Polytechnique Grants of‌​‌ Université Le Havre Normandie.​​​‌
  • Adrien Mélot was scientific​ expert for the French​‌ National Research Agency (ANR)​​

10.1.7 Research administration

  • Laurent​​​‌ Mevel
    • deputy head of​ science of Inria Rennes​‌
    • member of Commisision d'Evaluation​​ at Inria
    • member of​​​‌ the jury CESAAR at​ Ministère de la Transition​‌ Écologique et Solidaire
  • Vincent​​ Le Cam
    • deputy co-head​​​‌ of COSYS department at​ Université Gustave Eiffel
  • Jean​‌ Dumoulin
    • member of Commisision​​ d'Evaluation des chercheurs du​​​‌ Ministère de la Transition​ Ecologique (MTE)
  • Xavier Chapeleau​‌
    • member of Commisision d'Evaluation​​ des chercheurs du Ministère​​​‌ de la Transition Ecologique​ (MTE)

10.2 Teaching -​‌ Supervision - Juries -​​ Educational and pedagogical outreach​​​‌

10.2.1 Teaching

  • Jean Dumoulin​
    • Licence Professionnelle TAM (Techniques​‌ Avancées en Maintenance): thermographie​​ infrarouge active, 30h, Université​​​‌ Paris-Est Créteil (UPEC), France​
    • Master 2 ITII, BTP,​‌ module Maintenance et réhabilitation​​ des ouvrages, Transferts thermiques​​​‌ dans les Structures :​ Des principes physiques à​‌ l'application sur site réel,​​ 12 h, Ecole Centrale​​​‌ de Nantes (ECN), France.​
  • Vincent Le Cam
    • Master​‌ Electrical Engineering (GEII), 3h​​ CM in M1, 4h​​​‌ CM in M2 on​ electronic systems and Structural​‌ Monitoring, Université Bretagne Sud,​​ Lorient, France
    • M2 ENSIM​​​‌ Le Mans, 5h CM​ (monitoring des structures par​‌ capteurs sans fils)
    • EC​​ Nantes, 4h CM +​​​‌ 32h TP (electronique embarquée,​ Linux et drivers)
    • Ecole​‌ d'Ingénieur Builders, 10h CM,​​ Caen
  • Xavier Chapeleau
    • M1​​​‌ ITI, fibre-optique, 8h, IUT​ Nantes
    • "Monitoring and auscultation​‌ : Optical fiber sensors",​​ Infrastar Training School, November​​​‌ 2025
  • Romain Noel
    • École​ des Mines de Saint-Étienne,​‌ Master 2, Fluid Mechanics​​ Applications: Plenary conference (2h)​​​‌
    • École des Mines de​ Saint-Étienne, Master 1, Advanced​‌ Fluid Mecanics: Lectures (6h)​​ + practical lessons (6h)​​​‌
    • École Centrale de Nantes,​ Master 2, Data Signal​‌ and Image: Lectures (4h)​​ + practical lessons (4h)​​​‌
    • École Polytech' Nantes, Master​ 1, Probabilty and Statistics:​‌ Lectures (12h) + practical​​ lessons (3h)
  • Christophe Droz​​​‌
    • MSc 1, Modélisation en​ Action, Dpt. Mathématiques, Université​‌ de Rennes (50h)
    • MSc​​ 2, Contrôle non destructif​​​‌ et identification, Dpt. Sciences​ pour la matière, Université​‌ de Rennes (20h)
  • Alvaro​​ Gavilan Rojas
    • Master 2,​​​‌ Mécanique et Matériaux, Contrôle​ non destructif et identification,​‌ 1.5h CM + 5h​​ TD, Université de Rennes​​​‌
  • Lucas Rouhi
    • L1 Biologie,​ Environnement et Chimie du​‌ Vivant (BECV), 57h TD​​ en mathématiques, 6h TP​​​‌ initiation Python, Université de​ Rennes
  • Nicolas Madinier
    • STP03​‌ MECA, mécanique du solide,​​ 22h TD, INSA Rennes​​​‌
  • Boris Lossouarn
    • From september​ 2025 : International Master​‌ (M2), Smart structures -​​ Piezoelectric shunt damping, Cnam,​​​‌ Paris (15h)

10.2.2 Supervision​

PhD students
  • Clément Rigal,​‌ Modélisation multi-échelle d'écoulements convectifs​​ avec des matériaux à​​​‌ changement de phase micro-encapsulés​ à travers un milieu​‌ poreux, Y. Hoarau,​​ D. Funfschilling, Romain Noel​​​‌ , A. Chouippe, Ecole​ doctorale MSTII, defense 07/2025.​‌
  • Mira Kabbara, Modélisation et​​ caractérisation de capteurs à​​​‌ fibre optique continus,​ Qinghua Zhang , F.​‌ Bourquin, Xavier Chapeleau ,​​ Ecole doctorale Matisse, defense​​​‌ 12/2025.
  • Arij Khaled Fawaz,​ Etude de l'évolution des​‌ lois cohésives d'interface en​​ mode II pour un​​​‌ assemblage collé sous charge​ en milieu marin,​‌ S. Chataigner, E. Lepretre,​​ Xavier Chapeleau , Ecole​​ doctorale SIS, defense 11/2025.​​​‌
  • Alvaro Gavilan Rojas, Reduced‌ order models for non-destructive‌​‌ evaluation of periodic structures​​, Christophe Droz ,​​​‌ Qinghua Zhang and O.‌ Robin, Ecole doctorale Matisse,‌​‌ defense 12/2025.
  • Nina Delette,​​ Development of data-driven approaches​​​‌ for physics-informed wind-turbine digital‌ twins and application to‌​‌ real-world data, Laurent​​ Mevel , E. Denimal​​​‌ and J.-L. Pfister, Ecole‌ doctorale Matisse, since 11/2023.‌​‌
  • Nikhil Mahar, Machine learning​​ techniques for SHM,​​​‌ Laurent Mevel and S.‌ Sen, IIT Mandi, since‌​‌ 09/2023.
  • Marios Kaminiotis, Embedded​​ self-powered sensor devices for​​​‌ passive monitoring of composite‌ components, Vincent Le‌​‌ Cam , Romain Noel​​ and Bastien Chapuis, Ecole​​​‌ docotrale STIC, since 01/2024.‌
  • Zakariae Moutaouakil, Estimating/Modelling the‌​‌ statistical degradation laws of​​ the secondary road network​​​‌ from video-based pavement monitoring‌ devices, Laurent Mevel‌​‌ , Ph. Foucher, and​​ Vincent Baltazart , within​​​‌ the scope of the‌ ROAD-AI project with Cerema,‌​‌ since 10/2024.
  • Clément Bardet,​​ Simulation of multiphase flow​​​‌ coupled with temperature using‌ Lattice Boltzmann Method and‌​‌ chemical potential, Laurent​​ Mevel and Romain Noel​​​‌ , Ecole doctorale Matisse,‌ since 10/2024.
  • Lucas Rouhi,‌​‌ Non-local architected meta-structures for​​ lightweight vibro-acoustic design,​​​‌ Christophe Droz , Qinghua‌ Zhang , Ecole Doctorale‌​‌ Matisse, since 09/2024.
  • Benoit​​ Senard, An algebraic framework​​​‌ for phononic systems modelling‌, Christophe Droz ,‌​‌ Michael Doehler , Ecole​​ Doctorale Matisse, since 10/2024.​​​‌
  • Hamado Ouedraogo, Numerical Mutli-scale‌ Simulation of Evaporation and‌​‌ Imbibition of Building Porous​​ Material, Romain Noel​​​‌ and Christian La Borderie,‌ École doctorale sciences exactes‌​‌ et leurs applications, since​​ 10/2025.
  • Hovanes Boksyan, Digital​​​‌ twin for the monitoring‌ of welded components,‌​‌ Michael Doehler , Christophe​​ Droz , Fan Zhang​​​‌ and Philippe Amazouga (CETIM),‌ Ecole Doctorale Matisse, since‌​‌ 10/2025.
  • Pierre Lague, Artificial​​ Intelligence for Structural Resilience​​​‌ Optimization under Severe Vibratory‌ Stress, Christophe Droz‌​‌ , Michael Doehler ,​​ Nicolas Gutowski (Université Angers),​​​‌ Sébastien Aubin (DGA TT),‌ Ecole Doctorale Matisse, since‌​‌ 10/2025
  • Antoine Barré, Taking​​ into account metrology drift​​​‌ in long term wireless‌ sensor networks applied to‌​‌ SHM, Vincent Le​​ Cam , Julien Le​​​‌ Scornec , Laurent Mevel‌ , David Betaille (UGE),‌​‌ UGE, since 11/2025
  • Louis​​ Ramseyer, Designing next-generation seismic​​​‌ metamaterials with hybrid particle-‌ and wave-based simulations,‌​‌ Christophe Droz , Romain​​ Noel , Adrien Mélot​​​‌ , Ecole Doctorale Matisse,‌ since 11/2025
  • Valentin Mouton,‌​‌ Reductionist Deep Learning for​​ Mechanical Engineering, Adrien​​​‌ Mélot , Emmanuel Rigaud‌ and Joel Perret-Liaudet, Ecole‌​‌ Centrale Lyon, since 2023​​
  • Lisa Schwegmann, Vibration-based damage​​​‌ localization on civil structures‌, Michael Doehler and‌​‌ Volkmar Zabel, University of​​ Rostock, since 2025
  • Matthieu​​​‌ Marion, Vibration analysis of‌ metallic structures filled with‌​‌ damping materials, Boris​​ Lossouarn , Lucie Rouleau​​​‌ and Jean-François Deü, Conservatoire‌ national des arts et‌​‌ métiers and Naval Group​​ (Cifre), since 2022
  • Arthur​​​‌ Haudeville, Vibration mitigation of‌ hydrofoils using piezoelectric shunt‌​‌ damping, ANR ASTRID​​ HYDRAVIB, Boris Lossouarn and​​​‌ Xavier Amandolèse, Conservatoire national‌ des arts et métiers,‌​‌ Christophe Giraud-Audine and Olivier​​ Thomas, Arts et Métiers​​​‌ Lille, since 2023
  • Pierre‌ Flament, Vibration damping of‌​‌ multiple resonances through interconnected​​​‌ piezoelectric networks, Boris​ Lossouarn and Jean-François Deü,​‌ Conservatoire national des arts​​ et métiers and Naval​​​‌ Group (Cifre-Défense), since 2023​
  • Murilo Freitas, The Use​‌ of Climate and Meteorogical​​ Parameters to Model thermomecanical​​​‌ Pavement Ageing, Romain​ Noel , Mohamed Belmokhter​‌ and Pierre Hornych, EDSIS,​​ since 2024
  • Salahedine Djaoui,​​​‌ Mechanical & Thermal Optimization​ of a Solar Energy​‌ Harvesting Road, Romain​​ Noel , Éric Gennesseaux,​​​‌ Thierry Sedran, Florian Huchet​ and Emmanuel Chailleux, EDSIS,​‌ since 2024
Postdocs and​​ research engineers
  • Boualem Merainani,​​​‌ postdoc funded by SNCF​ then european Project KDT​‌ JU BRIGHTER, supervised by​​ Jean Dumoulin , 09/2021-12/2025.​​​‌
  • Neha Aswal, postdoc funded​ by BIENVENÜE, supervised by​‌ Qinghua Zhang and Laurent​​ Mevel , 12/2023-11/2025.
  • O​​​‌ A Shereena, postdoc at​ IIT Mandi, co-supervised by​‌ Laurent Mevel , since​​ 09/2023.
  • Julian Legendre, postdoc​​​‌ at Inria, co-supervised by​ Laurent Mevel , Jean​‌ Dumoulin and Thibaud Toullier​​ , 09/2024–08/2025.
  • Nicolas Madinier,​​​‌ postdoc in ANR JCJC​ at Inria, supervised by​‌ Christophe Droz , 09/2025-02/2027.​​
  • Antoine Barré, research engineer,​​​‌ DIAM, supervised by Vincent​ Le Cam , 11/2024–10/2025.​‌
  • Nathanaël Gey, Junior Research​​ Engineer in CityFAB CD92​​​‌ project since 11/2024, then​ Sci-ty TAPAS, co-supervised by​‌ Thibaud Toullier and Jean​​ Dumoulin , then since​​​‌ 04/2025 by Thibaud Toullier​ and Arthur Bouché .​‌
  • Jean-Noël Coueron, engineer, in​​ OBLiX-premat, supervised by Romain​​​‌ Noel , 02/2025-01/2026.
  • Adji​ Touré, engineer and co-head​‌ of Geronimo-EA project, supervised​​ by Vincent Le Cam​​​‌ , 10/2025-09/2027
  • Antoine Morvan,​ postdoc in ANR ASTRID​‌ HYDRAVIB at École navale​​ and Cnam, co-supervised by​​​‌ Boris Lossouarn , 09/2024-03/2026​
Internships
  • Nino Landormy (IMT​‌ Atlantique), Digitalizing an NDT​​ measurement process for civil​​​‌ engineering operators, apprenticeship supervised​ by Vincent Baltazart ,​‌ Romain Noel and Thibaud​​ Toullier , 10/2023–09/2026.
  • Adji​​​‌ Toure (EC Nantes), embedded​ software for GERONIMO system,​‌ apprenticeship supervised by Arthur​​ Bouche , 09/2022–08/2025.
  • Coralie​​​‌ Thuillier (ENS), Plateforme remote​ HPC pour la modélisation​‌ et la visualisation de​​ simulations dynamiques, 09/2025-04/2026.
  • Omar​​​‌ Laouiti, M2 (Univ Strasbourg),​ Flow in a porous​‌ medium with a thermal​​ mPCM concentration, supervised by​​​‌ Romain Noel , 02-08/2025​
  • Hamza Saissi (ENSIMAG), Study​‌ of a water tank​​ subjected to stochastic excitation,​​​‌ M1 internship, supervised by​ Romain Noel and Christophe​‌ Droz , 05-09/2025
  • Methmika​​ Athulkotte (EPF Engineering School),​​​‌ Modelling Seismic Surface Wave​ Scattering through Subsurface Heterogeneities:​‌ Development of Simulation Code,​​ M2 internship, supervised by​​​‌ Christophe Droz and Romain​ Noel , 05-10/2025
  • Nino​‌ Dos Santos (UBS Lorient),​​ Energy performance study of​​​‌ a hybrid solar road​ demonstrator in a controlled​‌ and then natural environment,​​ M1, supervised by Jean​​​‌ Dumoulin , 04-06/2025
  • Lucas​ Czamanski Meireles (Ecole Centrale​‌ Lyon), Weather forecasts for​​ boundary conditions of a​​​‌ finite element model of​ an energy-harvesting pavement, supervised​‌ by Jean Dumoulin and​​ Thibaud Toullier , 04-10/2025​​​‌
  • Lucas Doula (UBS Lorient),​ GPSd Porting to PEGASE4​‌ and Synchronization Accuracy Qualification,​​ M1, supervised by Vincent​​​‌ Le Cam , 04-08/2025​
  • Maxence Bouleau (Polytech Nantes),​‌ Deployment of a Novel​​ UWB Wireless Communication Using​​​‌ the Spark Development Kit​ for the DIAM Use​‌ Case, supervised by Vincent​​ Le Cam , 06-08/2025​​
  • Hovanes Boksyan (INP Grenoble),​​​‌ Data Processing and Fusion‌ for Fatigue-Induced Damage Detection,‌​‌ M2 internship, supervised by​​ Michael Doehler and Xavier​​​‌ Chapeleau , 02-07/2025
  • Mathis‌ Creff (Univ Rennes), Sous-structuration‌​‌ dynamique pour l'assemblage de​​ cellules unitaires, M1 internship,​​​‌ supervised by Christophe Droz‌ , 05-07/2025
  • Valentine Nayl‌​‌ (Univ Rennes), Échantillonnage adaptatif​​ pour la construction d'un​​​‌ modèle de substitution, M1‌ internship, supervised by Christophe‌​‌ Droz , 05-07/2025
  • Arthur​​ Kittler (Univ Strasbourg), Étude​​​‌ et mise en œuvre‌ de méthodes de détection‌​‌ automatique par machine learning​​ de désordres sur des​​​‌ images de chaussée, M2‌ internship, supervised by Philippe‌​‌ Foucher (Cerema), Alain Hebting​​ (Cerema) and Fabien Menant​​​‌ (UGE), 02-08/2025

10.2.3 Juries‌

  • Michael Doehler
    • External reviewer‌​‌ PhD Brandon O'Connell, "Novel​​ Probabilistic and Bayesian Approaches​​​‌ to Uncertainty Quantification for‌ Operational Modal Analysis". Sheffield‌​‌ University, UK, 02/2025.
    • External​​ reviewer PhD Armin Hermes,​​​‌ "High fidelity aeroelastic stability‌ analysis of complex blades‌​‌ in 3D flow". Technical​​ University of Denmark, Denmark,​​​‌ 03/2025.
  • Christophe Droz
    • PhD‌ external reviewer F. Qu‌​‌ "Frequency dependent and parametric​​ reduced order models for​​​‌ NVH simulation of metamaterial‌ structures", KU Leuven, Belgium,‌​‌ 12/2025.
    • CSI member of​​ PhD candidate K. Mouffok​​​‌ "Optimization and Management of‌ Event Logging in Distributed‌​‌ Embedded Networks", INSA Rennes.​​
    • CSI member of PhD​​​‌ candidate N. Klaimi "Sparse‌ model-based deep learning for‌​‌ massive MIMO". IETR Rennes.​​
  • Laurent Mevel
    • PhD Reviewer​​​‌ - Université de Lille.‌ ELIE ROUPHAEL, "Towards Stochastic‌​‌ Realization Theory for Linear​​ Switched Models". Defense October​​​‌ 24 2025.
  • Chapeleau Xavier‌
    • CSI member of PhD‌​‌ candidate: Bzeih Rayan, Development​​ of methods for analyzing​​​‌ fiber optic measurement data‌ to determine deformation and‌​‌ damage to underground concrete​​ structures., Nantes Université.
  • Romain​​​‌ Noel
    • CSI member of‌ PhD candidate: Khac Minh‌​‌ Tam Truong, Optimization of​​ Phylogenetic Compression Algorithms, Inria​​​‌ Rennes.
    • CSI member of‌ PhD candidate: Mahmoud Assaf,‌​‌ Numerical modeling and optimization​​ of two-phase flows with​​​‌ change of state, Polytech'Nantes.‌
    • CSI member of PhD‌​‌ candidate Badr Eddine Hamaid,​​ Decarbonizing cities on the​​​‌ climate change context: application‌ to the tertiary building,‌​‌ Univ. Eiffel.

10.2.4 Educational​​ and pedagogical outreach

  • Christophe​​​‌ Droz was involved in‌ Chiche!: a scientific mediation‌​‌ program promoting scientific careers​​ to high-school students (Lycée​​​‌ Sévigné).

10.3 Popularization

10.3.1‌ Specific official responsibilities in‌​‌ science outreach structures

  • Christophe​​ Droz is co-organizator of​​​‌ the Sci-Rennes seminar series‌ at the Inria center‌​‌ of the University of​​ Rennes (since Sep. 2022).​​​‌

10.3.2 Participation in Live‌ events

  • Boris Lossouarn actively‌​‌ contributed to the first​​ Carnot ARTS "Tech Show"​​​‌ on September 30, 2025‌ by presenting a vibration‌​‌ damping demonstrator for hydrofoils,​​ developed within the SMARTFOIL​​​‌ project (2019–2022, co-funded by‌ Carnot ARTS). The proposed‌​‌ experimental setup integrates piezoelectric​​ material to mitigate flow-induced​​​‌ vibrations. This live presentation‌ illustrated the scientific foundations‌​‌ and technological bricks enabling​​ next-generation smart structures for​​​‌ vibration analysis and control.‌

10.3.3 Others science outreach‌​‌ relevant activities

  • Vincent Le​​ Cam , Jean Dumoulin​​​‌ , Vincent Baltazart ,‌ Romain Noel , Xavier‌​‌ Chapeleau , Thibaud Toullier​​ , Arthur Bouché have​​​‌ participated in the Journées‌ Portes Ouvertes on the‌​‌ UGE campus in Nantes,​​​‌ with several demonstrators.
  • Vincent​ Le Cam organizes the​‌ stay of high school​​ students for internships on​​​‌ the UGE campus in​ Nantes.

11 Scientific production​‌

11.1 Major publications

11.2‌ Publications of the year‌​‌

International journals

Invited conferences

  • 36 inproceedings​​​‌C.Christophe Droz and‌ A. C.Alvaro C.‌​‌ Gavilan-Rojas. Reduced Frequency-driven​​ Bloch Wave Decomposition for​​​‌ Harmonic Analysis of Finite‌ Periodic Structures.PHONONICS‌​‌ 2025: 7th International Conference​​ on Phononic Crystals/Metamaterials/Metasurfaces, Phonon​​​‌ Transport, and Topological Phononics‌Phononics 2025 - 7th‌​‌ International Conference on Phononic​​ Crystals/Metamaterials/Metasurfaces, Phonon Transport, and​​​‌ Topological PhononicsSeoul, South‌ KoreaJune 2025,‌​‌ 58-59HALback to​​ text

International peer-reviewed conferences​​​‌

Conferences without proceedings‌

  • 58 inproceedingsA.Alvaro‌​‌ Gavilán-Rojas, Q.Qinghua​​ Zhang, O.Olivier​​​‌ Robin and C.C‌ Droz. Déflectométrie et‌​‌ théorie des structures périodiques​​ pour l'identification de nombres​​​‌ d'onde.CFM 2025‌ - 26ème Congrès Français‌​‌ de MécaniqueMetz, France​​August 2025HALback​​​‌ to text
  • 59 inproceedings‌V.Vincent Mahé,‌​‌ A.Adrien Mélot,​​​‌ B.Benjamin Chouvion and​ C.Christophe Droz.​‌ Wave-based reduction of finite​​ phononic structures with nonlinear​​​‌ boundary conditions.NODYCON​ 2025 - 4th International​‌ Nonlinear Dynamics ConferenceHoboken,​​ NJ, United StatesJune​​​‌ 2025, 1-1HAL​back to text
  • 60​‌ inproceedingsA.Adrien Mélot​​. Optimizing Bifurcations and​​​‌ Isolated Response Curves to​ Enhance the Performances of​‌ Nonlinear Energy Sinks.​​NODYCON 2025 - 4th​​​‌ International Nonlinear Dynamics Conference​Hoboken, NJ, United States​‌June 2025, 1-1​​HALback to text​​​‌

Edition (books, proceedings, special​ issue of a journal)​‌

  • 61 proceedingsProceedings of​​ the 11th International Operational​​​‌ Modal Analysis Conference (IOMAC​ 2025).IOMAC 2025​‌ - 11th International Operational​​ Modal Analysis ConferenceRennes,​​​‌ France2025HAL

Doctoral​ dissertations and habilitation theses​‌

  • 62 thesisC.Clément​​ Rigal. Multi-scale numerical​​​‌ study of a microencapsulated​ phase change materials laden​‌ flow in a porous​​ medium.Université de​​​‌ StrasbourgJuly 2025HAL​

Other scientific publications