Serial manipulators, which have large work space with respect to their own volume and occupied floor space, are the most common industrial robots by far. However, in many environments the situation is unstructured and less predictable, such as aboard a space station, a nuclear waste retrieval site, or a lunar base construction site. It is almost impossible to design a single robotic system which can meet all the requirements for every task. In these circumstances, it is important to deploy a modular reconfigurable robotic system, which is suitable to various task requirements. Modular reconfigurable robots have a variety of attributes that are well suited to for these conditions, including: the ability to serve as many different tools at once (saving weight), packing into compressed forms (saving space) and having high levels of redundany(increasing robustness). By easy disassembly and reassembly features, this serial modular robotic system will bring advantages to small and medium enterprise to save costs in the long term. This thesis focuses on developing such a serial reconfigurable modular robotic system with remote control functionality. The robotic arms are assembled by PowerCube Modules with cubic outward appearance. The control and power electronics are fully integrated on the connector block inside of the modules. Those modules are connected in series by looping through, and can work completely independently. The communication between robotic arms and PC controller is connected by the Control Area Network bus. CAN protocol detects and corrects transmission errors caused by electromagnetic interference. The local PC can directly control the robotic arm via Visual Basic code, and it can also be treated as server controller. Client PCs can access and control the robotic arm remotely through Socket communication mechanism with certain IP address and port number. A Java3D model is created on the client PC synchronously for customers online monitoring and control. The forward and inverse kinematic analysis is solved by Vector Algebraic Method. The Neutral Network Method is also introduced to improve the kinematic analysis. Multiple-layer networks are capable of approximating any function with finite number of discontinuities. For learning the inverse kinematics neural network needs information about coordinates, joint angles and actuator positions. The desired Cartesian coordinates are given as input to the neural network that returns actuator positions as output. The robot position is simulated using these actuator positions as reference values for each actuator.

This thesis describes the design and construction of modular robotic system. Proposal of its management and simulation parameters given.

Les récentes avancées technologiques en particulier dans le domaine de la miniaturisation de dispositifs robotiques laissent présager l'émergence de grands ensembles distribués de petits robots qui coopéreront en vue d'accomplir des tâches complexes (e.g., robotique modulaire, robots en essaims, microsystèmes électromécaniques distribués). Ces grands ensembles seront composés d'entités indépendantes, intelligentes et communicantes qui agiront comme un ensemble à part entière. Pour cela, elles s'auto-organiseront et collaboreront en vue d'accomplir des tâches complexes. Ces systèmes présenteront les avantages d'être plus polyvalents et plus robustes que les systèmes robotiques conventionnels tout en affichant un prix réduit. Ces ensembles formeront des systèmes distribués complexes dans lequel chaque entité sera un système embarqué à part entière avec ses propres capacités et ressources toute fois limitées. Coordonner de tels systèmes posent des défis majeurs et ouvrent de nouvelles opportunités dans l'algorithmique distribuée. Je défends la thèse qu'il faut d'ores et déjà identifier et implémenter des algorithmes distribués servant de primitives de base à la coordination de ces ensembles. Dans ce travail, nous nous focalisons sur une classe particulière de robots, à savoir les robots modulaires distribués formant de grands ensembles de modules fortement contraints en ressources (mémoire, calculs, etc.), placés dans une grille régulière et capables de communiquer entre voisins connexes uniquement. J'ai identifié et implémente trois primitives servant à la coordination de ces systèmes, à savoir l'élection d'un nœud central au réseau, la synchronisation temporelle ainsi que l'auto-reconfiguration. Dans ce manuscrit, je propose un ensemble d'algorithmes distribués réalisant ces primitives. J'ai évalué mes algorithmes en utilisant des expériences sur des modules matériels et en simulation sur des systèmes, composés de quelques dizaines à plus d'une dizaine de milliers de modules. Ces expériences montrent que nos algorithmes passent à l'échelle et sont adaptés aux grands ensembles distribués de systèmes embarqués avec des ressources fortement limités à la fois en mémoire et en calcul. / Technological advances especially in the miniaturization of robotic devices foreshadow the emergence of large-scale ensembles of small-size resource-constrained robots that distributively cooperate to achieve complex tasks (e.g., modular self-reconfigurable robots, swarm robotic systems, distributed microelectromechanical systems, etc.). These ensembles are formed from independent, intelligent and communicating units which act as a whole ensemble. These units cooperatively self-organize themselves to achieve common goals. These systems are tought to be more versatile and more robust than conventional robotic systems while having at the same time a lower cost.These ensembles form complex asynchronous distributed systems in which every unit is an embedded system with its own but limited capabilities. Coordination of such large-scale distributed embedded systems poses significant algorithmic issues and open for new opportunities in distributed algorithms. In my thesis, I defend the idea that distributed algorithmic primitives suitable for the coordination of these ensembles should be both identified and designed.In this work, we focus on a specific class of modular robotics systems, namely large-scale distributed modular robotic ensembles composed of resource-constrained modules that are organized in a lattice structure and which can only communicate with neighboring modules. We identified and implemented three building blocks, namely centrality-based leader election, time synchronization and self-reconfiguration.We propose a collection of distributed algorithms to realize these primitives. We evaluate them using both hardware experiments and simulations on systems ranging from a dozen of modules to more than a dozen of thousands of modules. We show that our algorithms scale well and are suitable for large-scale embedded distributed systems with scarce memory and computing resources.