Juan Cortés | LAAS-CNRS - Academia.edu (original) (raw)

Papers by Juan Cortés

Transportation Research Part E: Logistics and Transportation Review, 2014

ABSTRACT Supply chain employees must make decisions on when and how to react to potential and rea... more ABSTRACT Supply chain employees must make decisions on when and how to react to potential and realized supply chain disruptions. Drawing on regulatory focus theory, we examine how an individual’s regulatory focus, level of risk, as well as the uncertainty of the supply chain disruption affect willingness to pursue a new disruption mitigation strategy. Employing a vignette-based field experiment, we present and discuss findings related to supply chain risk decision making. These findings have implications for future behavioral supply chain risk research.KeywordsSupply chain risk managementDisruptionsVignette-based field experimentDecision making

Page 1. Th`ese présentée au Laboratoire d&amp;amp;#x27;Analyse et d&amp;amp;#x27;... more Page 1. Th`ese présentée au Laboratoire d&amp;amp;#x27;Analyse et d&amp;amp;#x27;Architecture des Syst`emes en vue de l&amp;amp;#x27;obtention du Doctorat de l&amp;amp;#x27;Institut National Polytechnique de Toulouse Ecole Doctorale Syst`emes Spécialité : Syst`emes Automatiques / Robotique par Juan Cortés ...

This paper describes an efficient approach to (self) collision detection and distance computation... more This paper describes an efficient approach to (self) collision detection and distance computations for complex articulated mechanisms such as molecular chains. The proposed algorithm called BioCD is particularly designed for samplingbased motion planning on molecular models described by long kinematic chains possibly including cycles. The algorithm considers that the kinematic chain is structured into a number of rigid groups articulated by preselected degrees of freedom. This structuring is exploited by a two-level spatially-adapted hierarchy. The proposed algorithm is not limited to particular kinematic topologies and allows good collision detection times. BioCD is also tailored to deal with the particularities imposed by the molecular context on collision detection. Experimental results show the effectiveness of the proposed approach which is able to process thousands of (self) collision tests per second on flexible protein models with up to hundreds of degrees of freedom.

Springer Tracts in Advanced Robotics, 2005

Page 1. Sampling-Based Motion Planning under Kinematic Loop-Closure Constraints Juan Cortés and T... more Page 1. Sampling-Based Motion Planning under Kinematic Loop-Closure Constraints Juan Cortés and Thierry Siméon LAAS-CNRS, Toulouse, France Abstract. Kinematic loop-closure constraints significantly increase the difficulty of motion planning for articulated mechanisms. ...

Computer Science Review, 2012

ABSTRACT Motion planning is a fundamental problem in robotics that has motivated research since m... more ABSTRACT Motion planning is a fundamental problem in robotics that has motivated research since more than three decades ago. A large variety of algorithms have been proposed to compute feasible motions of multi-body systems in constrained workspaces. In recent years, some of these algorithms have surpassed the frontiers of robotics, finding applications in other domains such as industrial manufacturing, computer animation and computational structural biology. This paper concerns the latter domain, providing a survey on motion planning algorithms applied to molecular modeling and simulation. Both the algorithmic and application sides are discussed, as well as the different issues to be taken into consideration when extending robot motion planning algorithms to deal with molecules. From an algorithmic perspective, the paper gives a general overview of the different extensions to sampling-based motion planners. From the point of view of applications, the survey deals with problems involving protein folding and conformational transitions, as well as protein–ligand interactions.

IFAC International Workshop on Intelligent Assembly and Disassembly, 2007, 2007

Page 1. DISASSEMBLY PATH PLANNING FOR OBJECTS WITH ARTICULATED PARTS Juan Cortés, Thierry Siméon ... more Page 1. DISASSEMBLY PATH PLANNING FOR OBJECTS WITH ARTICULATED PARTS Juan Cortés, Thierry Siméon LAAS-CNRS 7 Av. du Colonel-Roche, 31077 Toulouse, France Abstract: Sampling-based path planning ...

IEEE/ACM Transactions on Computational Biology and Bioinformatics, 2000

Abstract-This paper builds on the combination of robotic path planning algorithms and molecular m... more Abstract-This paper builds on the combination of robotic path planning algorithms and molecular modeling methods for computing large-amplitude molecular motions, and introduces voxel maps as a computational tool to encode and to represent such motions. We investigate several applications and show results that illustrate the interest of such representation.

Robotics: Science and Systems, 2005

Robotics and Automation, 2003. …, 2003

J. CortCs, T. Simeon LAAS-CNRS 7, avenue du Colonel-Roche 3 1077 Toulouse - France {jcortes,nic}@... more J. CortCs, T. Simeon LAAS-CNRS 7, avenue du Colonel-Roche 3 1077 Toulouse - France {jcortes,nic}@Iaas.fr ... Abstract Despite the increasing interest on parallel mechanisms during the last years, Jew researchers have addressed the motion planning problem for such ...

2014 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2014

The Transition-based RRT (T-RRT) is a variant of RRT developed for path planning on a continuous ... more The Transition-based RRT (T-RRT) is a variant of RRT developed for path planning on a continuous cost space, i.e. a configuration space featuring a continuous cost function. It has been used to solve complex, high-dimensional problems in robotics and structural biology. In this paper, we propose a multiple-tree variant of T-RRT, named Multi-T-RRT. It is especially useful to solve ordering-and-pathfinding problems, i.e. to compute a path going through several unordered waypoints. Using the Multi-T-RRT, such problems can be solved from a purely geometrical perspective, without having to use a symbolic task planner. We evaluate the Multi-T-RRT on several path planning problems and compare it to other path planners. Finally, we apply the Multi-T-RRT to a concrete industrial inspection problem involving an aerial robot.

2010 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2010

This paper proposes a planning framework to deal with the problem of computing the motion of a ro... more This paper proposes a planning framework to deal with the problem of computing the motion of a robot with dual arm/hand, during an object pick-and-place task. We consider the situation where the start and goal configurations of the object constrain the robot to grasp the object with one hand, to give it to the other hand, before placing it in its final configuration. To realize such a task, the proposed framework treats the grasp computation, for one or two multifingered hands, of an arbitrarily-shaped object, the exchange configuration and finally the motion of the robot arms and body. In order to improve the planner performance, a contextindependent grasp list is computed offline for each hand and for the given object as well as computed offline roadmap that will be adapted according to the environment composition. Simulation results show the planner performance on a complex scenario.

2012 IEEE International Conference on Bioinformatics and Biomedicine Workshops, 2012

ABSTRACT This paper presents a method, inspired by robot motion planning algorithms, to model con... more ABSTRACT This paper presents a method, inspired by robot motion planning algorithms, to model conformational transitions in proteins. The capacity of normal mode analysis to predict directions of collective large-amplitude motions is exploited to bias the conformational exploration. A coarse-grained elastic network model built on short fragments of three residues is proposed for the rapid computation of normal modes. The accurate reconstruction of the all-atom model from the coarse-grained one is achieved using closed-form inverse kinematics. Results show the capacity of the method to model conformational transitions of proteins within a few hours of computing time on a single processor. Tests on a set of ten proteins demonstrate that the computing time scales linearly with the protein size, independently of the protein topology. Further experiments on adenylate kinase show that main features of the transition between the open and closed conformations of this protein are well captured in the computed path.

Proceedings 2001 ICRA. IEEE International Conference on Robotics and Automation (Cat. No.01CH37164), 2001

This paper reports on our current effort for applying proba.bilistic path planning techniques to ... more This paper reports on our current effort for applying proba.bilistic path planning techniques to logistics and operation in huge industrial ins1;allations (eg, power plants). W e shav how the specific domain constraints impose a dedicated software architecture to take ad-vantage ...

2014 IEEE International Conference on Bioinformatics and Biomedicine (BIBM), 2014

Obtaining accurate representations of energy landscapes of biomolecules such as proteins and pept... more Obtaining accurate representations of energy landscapes of biomolecules such as proteins and peptides is central to structure-function studies. Peptides are particularly interesting, as they exploit structural flexibility to modulate their biological function. Despite their small size, peptide modeling remains challenging due to the complexity of the energy landscape of such highly-flexible dynamic systems. Currently, only samplingbased methods can efficiently explore the conformational space of a peptide. In this paper, we suggest to combine two such methods to obtain a full characterization of energy landscapes of small yet flexible peptides. First, we propose a simplified version of the classical Basin Hopping algorithm to quickly reveal the meta-stable structural states of a peptide and the corresponding low-energy basins in the landscape. Then, we present several variants of a robotics-inspired algorithm, the Transition-based Rapidly-exploring Random Tree, to quickly determine transition state and transition path ensembles, as well as transition probabilities between meta-stable states. We demonstrate this combined approach on the terminally-blocked alanine.

Atomic scale simulations of polymer materials is a topic of interest since it permits to reduce c... more Atomic scale simulations of polymer materials is a topic of interest since it permits to reduce costly experiments to determine their physicochemical properties. In this context, modeling heterogeneously ordered multichain systems such as amorphous polymers, remains a challenging problem. A recently proposed two-step method consists of iteratively generating the structures using a simplified energy model, and subsequently relaxing the system, considering a more accurate model, in order to reduce its potential energy. This work proposes an improvement of this method by integrating a novel relaxation technique, which applies analytical rebridging moves inspired by robotics. A comparative analysis using models of amorphous polyethylene with different sizes and densities shows that the rebridging scheme described here is very effective for the simulation of long alkanes.