Real Time Motion Generation for Mobile Robot

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Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Planification des mouvements optimaux dans les systèmes robotiques redondants pour un processus d'enroulement filamentaire composite automatisée

The thesis deals with the optimal motion planning in redundant robotic systems for automation of the composite lay-up processes. The primary goalis to improve the lay-up workcell productivity by developing a novel methodology of optimizing coordinated motions of the robotic manipulator,workpiece positioner and workspace extension unit,which ensure the shortest processing time and smooth movements of all mechanical components. In contrast to the previous works, the proposed methodology provides high computational efficiencyand also takes into account both the technological constraints and the robotic system constraints, which describe capacities of the actuators and are expressed by the maximum allowable velocities and accelerations in the actuated joints. The developed technique is based on conversion of the original continuous problem into a combinatorial one, where all possible configurations of the mechanical components are represented as a directed multi layergraph and the desired time-optimal motion is generated using dynamic programming principle for searching the shortest path on the graph satisfying the smoothness constraints. It is also proposed an enhancement of this technique by dividing the optimization procedure in two stages combining global and local searches. At the first stage, the developed algorithm is applied in the global search space generated with large discretization step. Then,the same technique is applied in the local search space, which is created with smaller step in the neighborhood of the obtained trajectory. The advantages of the developed methodology are confirmed by industrial implementation on the factory floor that deals with manufacturing of the high pressure vessel.La thèse traite de la planification des mouvements optimaux dans les systèmes robotiques redondants pour l'automatisation des processus d’enroulement filamentaire. L'objectif principal est d'améliorer la productivité des cellules de travail en développant une nouvelle méthodologie d'optimisation des mouvements coordonnés du robot manipulateur, du positionneur de pièce et de l'unité d'extension de l'espace de travail. Contrairement aux travaux précédents, la méthodologie proposée offre une grande efficacité de calcul et tient compte à la fois des contraintes technologiques et des contraintes du système robotique, qui décrivent les capacités des actionneurs et s'expriment par les vitesses et accélérations maximales admissibles dans les articulations actionnées. La technique développée est basée sur la conversion du problème continu original en un problème combinatoire, où toutes les configurations possibles des composants mécaniques sont représentées sous la forme d'un graphe multicouche dirigé et le mouvement temporel optimal est généré en utilisant le principe de programmation dynamique. Ce mouvement optimal correspond au plus court chemin sur le graphique satisfaisant les contraintes de lissage. Les avantages de la méthodologie développée sont confirmés par une application industrielle d’enroulement filamentaire pour la fabrication de pièces thermoplastiques au CETIM

Manipulator Motion Planning in Redundant Robotic System for Fiber Placement Process

International audienceThis paper proposes a new methodology for motion planning in redundant robotic system for the high-speed fiber placement technology. The considered system is composed of a 6-axis industrial robot and a one-axis actuated positioner. Compared to the previous works assuming constant rate, the particularity of this work lies in the time-optimal motion coordination based on the combinatorial optimization and the polynomial approximation techniques. Advantages of the developed technique are confirmed by an application example that deals with a planar robotic system for fiber placement

Optimization of the robot and positioner motion in a redundant fiber placement workcell

International audienceThe paper proposes a new methodology to optimize the robot and positioner motions in redundant robotic system for the fiber placement process. It allows user to find time-optimal smooth profiles for the joint variables while taking into account full capacities of the robotic system expressed by the maximum actuated joint velocities and accelerations. In contrast to the previous works, the proposed methodology possesses high computational efficiency and also takes into account the collision constraints. The developed technique is based on conversion of the original continuous problem into a discrete one, where all possible motions of the robot and the positioner are represented as a directed multi-layer graph and the desired time-optimal motions are generated using the dynamic programming that is applied sequentially for the rough and fine search spaces. To adjust the optimization results to the engineering requirements, the obtained trajectories are smoothed using the spline approximation. The advantages of the proposed methodology are confirmed by an application example that deals with a planar fiber placement robotic system

Optimal Trajectories Generation in Robotic Fiber Placement Systems

International audienceThe paper proposes a methodology for optimal trajectories generation in robotic fiber placement systems. A strategy to tune the parameters of the optimization algorithm at hand is also introduced. The presented technique transforms the original continuous problem into a discrete one where the time-optimal motions are generated by using dynamic programming. The developed strategy for the optimization algorithm tuning allows essentially reducing the computing time and obtaining trajectories satisfying industrial constraints. Feasibilities and advantages of the proposed methodology are confirmed by an application example

Optimal Motion Generation for Mobile Robot with Non-Skidding Constraint

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Optimal Coordination of Robot Motions with Positioner and Linear Track in a Fiber Placement Workcell

International audienceThe paper proposes a methodology for optimal coordination of motions in robotic systems with multiple redundant actuators. In contrast to our previous results dealing with a single redundant axis, the extended technique is proposed allowing the robot, positioner and linear track to be actuated simultaneously in order to reduce the total processing time. The developed technique transforms the original continuous problem into a discrete one where the desired time-optimal motions are presented as a shortest path on the task graph satisfying the problem-specific acceleration and velocity constraints imposed on the joint coordinates. The desired time optimal motions are generated using enhanced dynamic programming algorithm that considers both of these constraints. Two case studies are presented to demonstrate efficiency of the approach and evaluate benefits of simultaneous actuation of all robotic system axes

Optimization of Robot and Positioner Motions in Manufacturing of High-pressure Composite Vessels

International audienceThe paper proposes a technique for optimal motions generation in redundant robotic tape winding systems for manufacturing of high-pressure composite vessels. It also presents two industrial case studies dealing with the motion generation for basic types of winding lamina, helical and circumferential. The developed technique transforms the original continuous problem into a discrete one where the desired time-optimal motions are presented as a shortest path on the task graph satisfying the problem-specific acceleration and velocity constraints imposed on the joint coordinates. It allows generating the optimal trajectories using enhanced dynamic programming algorithm that considers both of these constraints. Efficiency of the developed technique is confirmed by simulation studies

Optimal Coordination of Robot Motions with Positioner and Linear Track in a Fiber Placement Workcell

International audienceThe paper proposes a methodology for optimal coordination of motions in robotic systems with multiple redundant actuators. In contrast to our previous results dealing with a single redundant axis, the extended technique is proposed allowing the robot, positioner and linear track to be actuated simultaneously in order to reduce the total processing time. The developed technique transforms the original continuous problem into a discrete one where the desired time-optimal motions are presented as a shortest path on the task graph satisfying the problem-specific acceleration and velocity constraints imposed on the joint coordinates. The desired time optimal motions are generated using enhanced dynamic programming algorithm that considers both of these constraints. Two case studies are presented to demonstrate efficiency of the approach and evaluate benefits of simultaneous actuation of all robotic system axes