In this thesis we address the constructibility problem for a ground vehicle moving across an environment instrumented with ranging sensors. When the measurements collected by the vehicle along the trajectory are sufficiently informative, the global constructibility property is achieved and the vehicle is able to localise itself in the environment without relying on prior information on its state. When this condition is not met, the system can still achieve local (or weak) constructibility, where localising the robot requires some initial information on the state, such as a sufficiently small set containing the initial position of the robot, or some inaccessible areas of the Cartesian plane. First, we address the global problem: we show that extending the well--known solutions for the positioning problem, e.g. trilateration, is not trivial and leads to unintuitive results where constructibility is not attained. By building an abstract trajectory, which contains all the relevant information to reconstruct the actual trajectory followed by the vehicle, we analyse how global constructibility properties are affected by the shape of the abstract trajectory, the number of sensors, their deployment in the environment, and the distribution of measurements among the beacons. To describe local constructibility, we build the Constructibility Gramian for a robot described by the unicycle kinematic model. We rely on this tool for a twofold aim: (a) we build the same abstract trajectory presented for the global analysis and define necessary and sufficient conditions to attain local constructibility, and (b) in an environment instrumented with two beacons and for straight trajectories followed by the vehicle, we measure local constructibility by means of the smallest eigenvalue of the Constructibility Gramian, and we analyse how this metric is affected by the geometry of the scenario, e.g. the distance between anchors, and the distance between the trajectory and the line joining the anchors. Lastly, we extend the devised results to multiagent systems, both for constructibility analysis and for trajectory planning algorithms. We build the Constructibility Gramian for the multiagent system with relative ranging measurements and assess local constructibility property. Then, we propose a trajectory planning algorithm where a pair of vehicles without a priori information achieve global constructibility with both absolute and relative measurements. Moreover, we propose a variation of the Constructibility Gramian, limited to the position variable and hence called Position Gramian, and use this tool in a Model Predictive Control framework to plan the trajectory of a tracker vehicle aiming at simultaneously localising itself and a collaborative target through ranging measurements.

Cette thèse s'intéresse au développement de lois de commande basées sur la perception auditive. Dans le domaine de l'audition robotique, le contrôle du robot à partir d'informations auditives est généralement basé sur des approches de localisation de source sonore. Cependant, la localisation de source en conditions réelles est un tâche complexe à résoudre. En environnement intérieur, les perturbations causées par le bruit, la réverbération ou même la structure du robot peuvent altérer le processus de localisation. Cette tâche de localisation devient encore plus complexe si la source et/ou le robot sont en mouvement. Aujourd'hui, en se restreignant aux systèmes binauraux, la localisation sonore en environnement réel n'est pas encore réalisable de manière robuste. A l'opposé, nous développons dans cette thèse une commande référencée capteurs, l'asservissement sonore, qui ne nécessite pas de localiser la source. Le mouvement du robot est directement reliée à la perception auditive: une tâche de positionnement est réalisée par une boucle de commande, où le mouvement du robot est régi par la dynamique d'indices sonores de bas niveau. Les résultats expérimentaux dans différentes conditions acoustiques et sur différentes plates-formes robotiques confirment la pertinence de cette approche en condition réelle. / This thesis is concerned about the development of a control framework based on auditory perception. In general, in robot audition, the motion control of a robot using hearing sense is based on sound source localization approaches. However, sound source localization under realistic conditions is a significant challenge to solve. In indoor environment perturbations caused by noise, reverberation or even the structure of the robot may alter the localization process. When considering dynamic scenes where the robot and/or the sound source might move, the degree of complexity of source localization raises to a higher level. As a result, sound source localization considering binaural setup is not achievable yet in real-world environments. By contrast, we develop in this thesis a sensor-based control approach, aural servo, that does not require to localize the source. The motion of the robot is straightly connected to the auditory perception: a positioning task is performed through a feedback loop where the motion of the robot is governed by the dynamic of low-level auditory features. Experimental results in various acoustic conditions and robotic platforms confirm the relevance of this approach for real-world environments.

Alors que l’utilisation d’un fauteuil roulant permet aux personnes en situation de handicap de compenser une perte de la mobilité, certaines personnes se voient privées de l’utilisation d’un fauteuil roulant électrique. En effet, la présence de troubles cognitifs ou de la perception visuelle altère la capacité à conduire sans danger. Dans ce contexte, l’accès à la mobilité peut être amélioré par l’apport d’aides techniques adaptées permettant de compenser la perte de mobilité dans tous types d’environnements. Alors que les premiers travaux sur les fauteuils roulants intelligents datent du début des années 80, aucune solution n’est à ce jour sur le marché ou dans les centres de rééducation. Ce travail vise à proposer un ensemble de solutions d’aide à la conduite de fauteuil roulant électrique conçu en collaboration. Le développement de telles aides techniques constitue de multiples défis robotiques mêlant techniques de détection innovantes et méthodes de contrôle partagé avec l’utilisateur. Dans ce travail, un simulateur de conduite visant à appuyer la recherche et le développement de nouvelles solutions robotiques est proposé. Puis des solutions bas coût d’assistance semiautonome à la conduite en intérieur et en extérieur sont détaillées. L’évaluation avec des participants sains nous permet de valider les méthodes mathématiques mises en oeuvre et de fournir des preuves de concept des solutions proposées. Enfin, les premières évaluations cliniques avec des usagers au Pôle MPR Saint Hélier montrent la validation de de la méthode proposée en termes de satisfaction des utilisateurs. / While the use of a wheelchair allows people with disabilities to compensate for a loss of mobility, people with severe disabilities are denied the use of a power wheelchair. Indeed, cognitive or visual perception impairments can affect the ability to drive safely. In this context, access to mobility can be improved by providing appropriate assistive technologies to compensate for loss of mobility in all types of environments. While the first research on smart wheelchairs dates back to the early 1980s, no solutions have yet been proposed on the market or in rehabilitation centers and other specialized structures. This work aims to propose a set of solutions for power wheelchair navigation assistance designed in close collaboration with users and therapists. The development of such assistive solutions faces multiple robotic challenges combining innovative detection techniques, shared control with the user. In this work, a driving simulator supporting research and development of new robotic solutions for wheelchair navigation assistance is proposed. Then low-cost semi-autonomous assistance solutions for navigation assistance in indoor and outdoor environments are detailed. The evaluation with able-bodied participants allows to validate the mathematical methods and provide proof of concept of the proposed solutions. Finally, the first clinical evaluations with regular users at Pôle MPR Saint Hélier show the validation of the proposed framework in terms of user satisfaction.

My work is aiming at establishing the bases of a semiotics of motion, in order to facilitate the programing of complex robotics systems. The objective is to build a symbolic model of the action, based on the analysis of the numerical functions that drive the motion (control and planning). The methodology comes from the well-known robotics concepts: motion-planning algorithms, control of redundant systems and task-function approach. The originality of the work is to consider the "task" as the unifying concept both to describe the motion and to control its execution. The document is organized in two parts. In the first part, the task-function control framework is extended to cover all the possible modalities of the robot. The objective is to absorb from the lowest-possible functional level the maximum of uncertainty factors. It is then not any more necessary to model these factors at the higher functional levels. This sensorimotor layer is then used as a basic action "vocabulary" that enables the system to be controlled with a higher-level interface. In the second part, this action vocabulary is used to provide a dedicated robotics programing language, to build motion-planning methods and to describe an observed movement. The proposed methods are generic and can be applied to a various systems, from robotics (redundant robots) to computer animation (virtual avatars). Nonetheless, the work is more specifically dedicated to humanoid robotics. Without forgetting other possible outlets, humanoid robotics provides a tangible applicative and experimental framework. It also leads toward the natural human motion, as presented in the end of the document.