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Tools to handle a control perception action loop on Gazebo
No full textThis repository was motivated by the need to show that it was possible to make fast control loop with gazebo (gz) without restarting complex launch files over and over. Gazebo as a system simulator is allowing to test a full control software stack. While it is well motivated for integrators it is however quite time consuming when one wants to test quickly a new motion generation scheme. At the same time gz since Harmonic offers the possibility to test various dynamical simulators such as bullet, bullet feathersone or DART which is of high interest for people interested in new dynamical simulators.This plugin was necessary to test simulations of almost two hundreds taxels
Solving Stengle's Example in Rational Arithmetic: Exact Values of the Moment-SOS Relaxations
No full textWe revisit Stengle's classical univariate polynomial optimization example whose constraint description is degenerate at the minimizers. We prove that the moment-SOS hierarchy of relaxation order has the exact value . For this we construct in rational arithmetic a dual polynomial sum-of-squares (SOS) certificate and a primal moment sequence representing a finitely atomic measure. The key ingredients are elementary trigonometric properties of Chebyshev and Gegenbauer polynomial, and a Christoffel-Darboux kernel argument
S-variable approach for generic convex polyhedra
No full textFor long the S-variable approach has proved its efficiency for addressing robustness issues with respect to matrix valued bounded, polytopic uncertainties. The results are extended in this paper to generic convex polyhedra thus allowing robustness analysis with respect to unbounded uncertainties. Results apply to rationnaly-dependent models with respect to such polyhedral uncertainties. Moreover the S-variable approach is proved to be enhanced thanks to a new affine rows-decoupled descriptor modeling of such systems. Examples of application of these results are a reinterpretation of the KYP-lemma as well as a reformulation of the links between sum-of-squares approach and the S-variable approach
Schrödinger and Euler-Bernoulli beam equations: structure-preserving discretization and equivalence as port-Hamiltonian systems
No full textInternational audienceIn this work, the classical equivalence between Schrödinger and Euler-Bernoulli beam partial differential equations (PDEs) as closed physical systems is extended to open physical systems using the port-Hamiltonian framework: first, a damped version of both these models is presented; second, the possible collocated inputs and outputs of the two models are parameterized in the most general way; and third, a structure-preserving discretization method for a class of one-dimensional Boundary-Controlled Port-Hamiltonian System (BC-PHS) with collocated boundary actuation and sensing is developed. Unlike the classical Partitioned Finite Element Method (PFEM) approach, the proposed discretization method makes it possible to obtain an ordinary differential equation regardless of the boundary conditions, preventing the emergence of a differential-algebraic equation in the case of mixed boundary conditions. This novelty, recently validated for the wave and Timoshenko beam equations, is now extended to PDEs with a secondorder differential operator. On the Schrödinger and Euler-Bernoulli equations, it is shown that the proposed numerical scheme can deal with a large type of boundary inputs and outputs
De la théorie à l'application industrielle : sélection et évaluation fondées sur des principes des méthodes de tests de non-régression
No full textNational audienceThe optimization of regression testing (RT) has been widely studied in the literature, and numerous methods exist. This work focuses on the practical deployment of RT methods in Industry. It addresses the following challenge: among the many existing methods, how to determine which ones are suitable for a specific industrial context?The thesis investigates a taxonomy-based approach to assist practitioners in the characterization of their RT problem, the selection of feasible candidate solutions and their evaluation in the industrial context. The contributions are the following: 1) the proposal of an approach that builds on a recent taxonomy of RT concepts, allowing for an alignment between RT problems and candidate RT solutions; 2) an empirical assessment of the approach through a real-world case study, involving two software systems embedded into connected vehicles; 3) feedback on the usability of the taxonomy; 4) feedback on the real-world problem, including the constraints faced in the evaluation of RT methods, and the results of this evaluation. The approach delivered on its promise, enabling the identification of RT methods suitable for the studied problem. However, this success came at the cost of difficulties due to unclear taxonomy elements, missing ones, and errors in the taxonomy-based classification of methods. We conclude that the proposed alignment between problems and solution is relevant in principle, but that the taxonomy would have to mature. Our work identifies avenues for improvement.L'optimisation du test de non régression a été très étudié dans la littérature, donnant lieu à de nombreuses méthodes. Nos travaux s'intéressent au déploiement de ces méthodes dans l'industrie. Ils traitent le défi suivant : parmi les nombreuses méthodes de test de non régression, comment déterminer celles qui seront les plus adaptées à un contexte industriel spécifique ?La thèse explore une méthodologie pour aider les praticiens à caractériser leur problème de test, sélectionner les méthodes candidates applicables et lesévaluer dans le contexte industriel. Les contributions sont : 1) la définition d'une méthodologie basée sur une taxonomie récente du test de non-régression, permettant un alignement entre le problème de test et les solutions candidates ; 2) l'évaluation empirique de la méthodologie par une étude cas industrielle, impliquant deux systèmes embarqués dans des véhicules connectés; 3) des retours détaillés sur l'utilisation de la taxonomie ; 4) des retours sur l'exemple réel étudié, incluant l'analyse des contraintes rencontrées pour évaluer les méthodes candidates, ainsi que l'analyse des résultats de cette évaluation. La méthodologie a tenu ses promesses, permettant de trouver des méthodes de test de non régression adaptées au problème étudié. Cependant, ce succès a été obtenu au prix de difficultés dues à des concepts peu clairs ou manquants dans la taxonomie, et à des erreurs dans la classification des méthodes selon la taxonomie. Nous concluons que l'alignement proposé entre problèmes et solutions est pertinent dans son principe, mais que la taxonomie aurait besoin mûrir. Nos travaux identifient des pistes d'amélioration
Acting, Planning and Learning
No full textInternational audienceAI's next big challenge is to master the cognitive abilities needed by intelligent agents that perform actions. Such agents may be physical devices such as robots, or they may act in simulated or virtual environments through graphic animation or electronic web transactions. This book is about integrating and automating these essential cognitive abilities: planning what actions to undertake and under what conditions, acting (choosing what steps to execute, deciding how and when to execute them, monitoring their execution, and reacting to events), and learning about ways to act and plan. This comprehensive, coherent synthesis covers a range of state-of-the-art approaches and models – deterministic, probabilistic (including MDP and reinforcement learning), hierarchical, nondeterministic, temporal, spatial, and LLMs – and applications in robotics. The insights it provides into important techniques and research challenges will make it invaluable to researchers and practitioners in AI, robotics, cognitive science, and autonomous and interactive systems
Online matching for the multiclass stochastic block model
No full textInternational audienceWe consider the problem of sequential matching in a stochastic block model with several classes of nodes and generic compatibility constraints. When the probabilities of connections do not scale with the size of the graph, we show that under the NCOND condition, a simple max-weight type policy allows to attain an asymptotically perfect matching while no sequential algorithm attain perfect matching otherwise. The proof relies on a specific Markovian representation of the dynamics associated with Lyapunov techniques
Soft, transparent and bioresorbable microelectrode array for transient electrophysiological recordings
No full textTransparent microelectrode arrays that enable multimodal investigation of spatiotemporal electrophysiological activity are critical tools for advancing the understanding of excitable tissues such as the brain, heart, and peripheral nerves. Traditional implantable devices are engineered for chronic use but require surgical removal when they fail or are no longer needed.In contrast, bioresorbable systems that naturally dissolve after serving temporary functions offer a compelling alternative, eliminating the risks and costs of extraction procedures. Here, we present the design, fabrication, and validation of a soft, fully bioresorbable, and optically transparent MEA platform for transient, bidirectional interfacing with living tissues. The device provides high-resolution electrical mapping of dynamic activity. We report precise characterization of electrochemical performance, mechanical properties, bioresorption kinetics, and biocompatibility. While validated in models of cardiac function, this platform establishes a versatile foundation for bioresorbable electrophysiological technologies with applications ranging from postsurgical monitoring of transient conditions to the study and treatment of neurological and neurodegenerative disorders.</p
Quantum bioelectrochemical (QBIOL) software based on point stochastic processes
No full textInternational audienc
III-Nitride MEMS drum resonators on flexible metal substrates
No full textInternational audienceWe present a simple and efficient process for fabricating III-Nitride (III-N) mechanical resonators on flexible metal substrates. This method combines Van der Waals epitaxy of III-N epilayers with the deposition of a thick metal stressor atop the III-N layers. During thermal treatment, the 30 μm thick metal stressor deposited on a 300 nm AlGaN/500 nm GaN layer grown on a 3 nm two-dimensional hexagonal-Boron Nitride (2D h-BN) release layer, initiates a one-step Self-Lift-Off and Transfer (SLOT) process. This process effectively transfers the III-N heterostructure from the h-BN/Sapphire growth wafer to the flexible metal stressor substrate. Additional local etching of the metal stressor and deposition of front electrodes allow for releasing self-standing III-N layers with integrated actuation. Fabricated III-N MEMS drum resonators were analyzed using optical profilometry and laser Doppler vibrometer, enabling the observation of static deflections and distinct vibration modes. Finite element method (FEM) simulations were also performed to further understand experimental observations and assess the mechanical properties of the released III-N layers, particularly enabling the estimation of stress in the GaN and AlGaN released layers. This straightforward approach not only provides a practical solution for cost-effective III-N MEMS resonators but also ensures flexibility, and crack-free structures