Robotics

  1. Robust Multi-Robot Optimal Path Planning with Temporal Logic Constraints.

    Authors: Stephen L. Smith, Calin Belta, Alphan Ulusoy, Xu Chu Ding
    Subjects: Robotics
    Abstract

    In this paper we present a method for automatically planning robust optimal
    paths for a group of robots that satisfy a common high level mission
    specification. Each robot's motion in the environment is modeled as a weighted
    transition system, and the mission is given as a Linear Temporal Logic (LTL)
    formula over a set of propositions satisfied by the regions of the environment.
    In addition, an optimizing proposition must repeatedly be satisfied.

  2. Acoustic Communication for Medical Nanorobots.

    Authors: Tad Hogg, Robert A. Freitas Jr
    Subjects: Robotics
    Abstract

    Communication among microscopic robots (nanorobots) can coordinate their
    activities for biomedical tasks. The feasibility of in vivo ultrasonic
    communication is evaluated for micron-size robots broadcasting into various
    types of tissues. Frequencies between 10MHz and 300MHz give the best tradeoff
    between efficient acoustic generation and attenuation for communication over
    distances of about 100 microns.

  3. Experimental Characterization of Robot Arm Rigidity in Order to Be Used in Machining Operation.

    Authors: Alain Gérard, Miron Zapciu, Jean-Yves K'Nevez, Mehdi Cherif
    Subjects: Robotics
    Abstract

    Attempts to install a rotating tool at the end of a robot arm
    poly-articulated date back twenty years, but these robots were not designed for
    that. Indeed, two essential features are necessary for machining: high rigidity
    and precision in a given workspace. The experimental results presented are the
    dynamic identification of a poly-articulated robot equipped with an integrated
    spindle. This study aims to highlight the influence of the geometric
    configuration of the robot arm on the overall stiffness of the system.

  4. Dynamic behavior analysis for a six axis industrial machining robot.

    Authors: Claudiu-Florinel Bisu, Alain Gérard, Medhi Cherif, Jean-Yves K'Nevez
    Subjects: Robotics
    Abstract

    The six axis robots are widely used in automotive industry for their good
    repeatability (as defined in the ISO92983) (painting, welding, mastic
    deposition, handling etc.). In the aerospace industry, robot starts to be used
    for complex applications such as drilling, riveting, fiber placement, NDT, etc.
    Given the positioning performance of serial robots, precision applications
    require usually external measurement device with complexes calibration
    procedure in order to reach the precision needed.

  5. Umgebungserfassungssystem fuer mobile Roboter (environment logging system for mobile autonomous robots).

    Authors: Dirk Hesselbach
    Subjects: Robotics
    Abstract

    This diploma thesis describes the theoretical bases, the conception of the
    module and the final result of the development process in application. for the
    environment logging with a small mobile robot for interiors should be sketched
    an economical alternative to the expensive laser scanners. the structure, color
    or the material of the objects in the radius of action, as well as the
    environment brightness and illuminating are to have thereby no influence on the
    results of measurement.

  6. Contextually Guided Semantic Labeling and Search for 3D Point Clouds.

    Authors: Thorsten Joachims, Abhishek Anand, Hema Swetha Koppula, Ashutosh Saxena
    Subjects: Robotics
    Abstract

    RGB-D cameras, which give an RGB image to- gether with depths, are becoming
    increasingly popular for robotic perception. In this paper, we address the task
    of detecting commonly found objects in the 3D point cloud of indoor scenes
    obtained from such cameras. Our method uses a graphical model that captures
    various features and contextual relations, including the local visual
    appearance and shape cues, object co-occurence relationships and geometric
    relationships.

  7. Robot Companions: Technology for Humans.

    Authors: Serge Kernbach
    Subjects: Robotics
    Abstract

    Creation of devices and mechanisms which help people has a long history.
    Their inventors always targeted practical goals such as irrigation, harvesting,
    devices for construction sites, measurement, and, last but not least, military
    tasks for different mechanical and later mechatronic systems. Development of
    such assisting mechanisms counts back to Greek engineering, came through Middle
    Ages and led finally in XIX and XX centuries to autonomous devices, which we
    call today "Robots".

  8. Awareness and Self-Awareness for Multi-Robot Organisms.

    Authors: Serge Kernbach
    Subjects: Robotics
    Abstract

    Awareness and self-awareness are two different notions related to knowing the
    environment and itself. In a general context, the mechanism of self-awareness
    belongs to a class of co-called "self-issues" (self-* or self-star):
    self-adaptation, self-repairing, self-replication, self-development or
    self-recovery. The self-* issues are connected in many ways to adaptability and
    evolvability, to the emergence of behavior and to the controllability of
    long-term developmental processes.

  9. Collective Energy Foraging of Robot Swarms and Robot Organisms.

    Authors: Serge Kernbach
    Subjects: Robotics
    Abstract

    Cooperation and competition among stand-alone swarm agents increase
    collective fitness of the whole system. A principally new kind of collective
    systems is demonstrated by some bacteria and fungi, when they build symbiotic
    organisms. Symbiotic life forms emerge new functional and self-developmental
    capabilities, which allow better survival of swarm agents in different
    environments. In this paper we consider energy foraging scenario for two
    robotic species, swarm robots and symbiotic robot organism.

  10. A Behavior-based Approach for Multi-agent Q-learning for Autonomous Exploration.

    Authors: Dip Narayan Ray, Somajyoti Majumder, Sumit Mukhopadhyay
    Subjects: Robotics
    Abstract

    The use of mobile robots is being popular over the world mainly for
    autonomous explorations in hazardous/ toxic or unknown environments. This
    exploration will be more effective and efficient if the explorations in unknown
    environment can be aided with the learning from past experiences. Currently
    reinforcement learning is getting more acceptances for implementing learning in
    robots from the system-environment interactions. This learning can be
    implemented using the concept of both single-agent and multiagent.

  11. Heterogeneity for Increasing Performance and Reliability of Self-Reconfigurable Multi-Robot Organisms.

    Authors: S. Kernbach, F. Schlachter, R. Humza, J. Liedke, S. Popesku, S. Russo, T. Ranzani, L. Manfredi, C. Stefanini, R. Matthias, Ch. Schwarzer, B. Girault, P. Alschbach, E. Meister, O.Scholz
    Subjects: Robotics
    Abstract

    Homogeneity and heterogeneity represent a well-known trade-off in the design
    of modular robot systems. This work addresses the heterogeneity concept, its
    rationales, design choices and performance evaluation. We introduce challenges
    for self-reconfigurable systems, show advances of mechatronic and software
    design of heterogeneous platforms and discuss experiments, which intend to
    demonstrate usability and performance of this system.

  12. Least Squares Temporal Difference Actor-Critic Methods with Applications to Robot Motion Control.

    Authors: Jing Wang, Xu Chu Ding, Reza Moazzez Estanjini, Morteza Lahijanian, Calin A. Belta, Ioannis Ch. Paschalidis
    Subjects: Robotics
    Abstract

    We consider the problem of finding a control policy for a Markov Decision
    Process (MDP) to maximize the probability of reaching some states while
    avoiding some other states. This problem is motivated by applications in
    robotics, where such problems naturally arise when probabilistic models of
    robot motion are required to satisfy temporal logic task specifications. We
    transform this problem into a Stochastic Shortest Path (SSP) problem and
    develop a new approximate dynamic programming algorithm to solve it.

  13. Exploiting the Passive Dynamics of a Compliant Leg to Develop Gait Transitions.

    Authors: Harold Roberto Martinez Salazar, Juan Pablo Carbajal
    Subjects: Robotics
    Abstract

    In the area of bipedal locomotion, the spring loaded inverted pendulum (SLIP)
    model has been proposed as a unified framework to explain the dynamics of a
    wide variety of gaits. In this paper, we present a novel analysis of the
    mathematical model and its dynamical properties. We use the perspective of
    hybrid dynamical systems to study the dynamics and define concepts such as
    partial stability and viability. With this approach, on the one hand, we
    identified stable and unstable regions of locomotion.

  14. Integrating Generic Sensor Fusion Algorithms with Sound State Representations through Encapsulation of Manifolds.

    Authors: Lutz Schröder, Christoph Hertzberg, René Wagner, Udo Frese
    Subjects: Robotics
    Abstract

    Common estimation algorithms, such as least squares estimation or the Kalman
    filter, operate on a state in a state space S that is represented as a
    real-valued vector. However, for many quantities, most notably orientations in
    3D, S is not a vector space, but a so-called manifold, i.e. it behaves like a
    vector space locally but has a more complex global topological structure. For
    integrating these quantities, several ad-hoc approaches have been proposed.

  15. Optimal Multi-Robot Path Planning with Temporal Logic Constraints.

    Authors: Stephen L. Smith, Calin Belta, Daniela Rus, Alphan Ulusoy, Xu Chu Ding
    Subjects: Robotics
    Abstract

    In this paper we present a method for automatically planning optimal paths
    for a group of robots that satisfy a common high level mission specification.
    Each robot's motion in the environment is modeled as a weighted transition
    system. The mission is given as a Linear Temporal Logic formula. In addition,
    an optimizing proposition must repeatedly be satisfied. The goal is to minimize
    the maximum time between satisfying instances of the optimizing proposition.
    Our method is guaranteed to compute an optimal set of robot paths.

  16. Sampling-based Algorithms for Optimal Motion Planning.

    Authors: Emilio Frazzoli, Sertac Karaman
    Subjects: Robotics
    Abstract

    During the last decade, sampling-based path planning algorithms, such as
    Probabilistic RoadMaps (PRM) and Rapidly-exploring Random Trees (RRT), have
    been shown to work well in practice and possess theoretical guarantees such as
    probabilistic completeness. However, little effort has been devoted to the
    formal analysis of the quality of the solution returned by such algorithms,
    e.g., as a function of the number of samples.

  17. Patient-Specific Prosthetic Fingers by Remote Collaboration - A Case Study.

    Authors: John-John Cabibihan
    Subjects: Robotics
    Abstract

    The concealment of amputation through prosthesis usage can shield an amputee
    from social stigma and help improve the emotional healing process especially at
    the early stages of hand or finger loss. However, the traditional techniques in
    prosthesis fabrication defy this as the patients need numerous visits to the
    clinics for measurements, fitting and follow-ups. This paper presents a method
    for constructing a prosthetic finger through online collaboration with the
    designer.

  18. Visual Localisation of Mobile Devices in an Indoor Environment under Network Delay Conditions.

    Authors: Alberto Alonso Fernández, Omar Álvarez Fres, Ignacio González Alonso, Huosheng Hu
    Subjects: Robotics
    Abstract

    Current progresses in home automation and service robotic environment have
    highlighted the need to develop interoperability mechanisms that allow a
    standard communication between the two systems. During the development of the
    DHCompliant protocol, the problem of locating mobile devices in an indoor
    environment has been investigated. The communication of the device with the
    location service has been carried out to study the time delay that web services
    offer in front of the sockets.

  19. Persistent Robotic Tasks: Monitoring and Sweeping in Changing Environments.

    Authors: Stephen L. Smith, Daniela Rus, Mac Schwager
    Subjects: Robotics
    Abstract

    We present controllers that enable mobile robots to persistently monitor or
    sweep a changing environment. The changing environment is modeled as a field
    which grows in locations that are not within range of a robot, and decreases in
    locations that are within range of a robot. We assume that the robots travel on
    given closed paths. The speed of each robot along its path is controlled to
    prevent the field from growing unbounded at any location. We consider the space
    of speed controllers that can be parametrized by a finite set of basis
    functions.

  20. Stiffness modelling of parallelogram-based parallel manipulators.

    Authors: Damien Chablat, Anatoly Pashkevich, Alexandr Klimchik, Stéphane Caro
    Subjects: Robotics
    Abstract

    The paper presents a methodology to enhance the stiffness analysis of
    parallel manipulators with parallelogram-based linkage. It directly takes into
    account the influence of the external loading and allows computing both the
    non-linear ``load-deflection" relation and relevant rank-deficient stiffness
    matrix. An equivalent bar-type pseudo-rigid model is also proposed to describe
    the parallelogram stiffness by means of five mutually coupled virtual springs.
    The contributions of this paper are highlighted with a parallelogram-type
    linkage used in a manipulator from the Orthoglide family.

  21. Integrating digital human modeling into virtual environment for ergonomic oriented design.

    Authors: Damien Chablat, Wei Zhang, Liang Ma, Fouad Bennis, Bo Hu
    Subjects: Robotics
    Abstract

    Virtual human simulation integrated into virtual reality applications is
    mainly used for virtual representation of the user in virtual environment or
    for interactions between the user and the virtual avatar for cognitive tasks.
    In this paper, in order to prevent musculoskeletal disorders, the integration
    of virtual human simulation and VR application is presented to facilitate
    physical ergonomic evaluation, especially for physical fatigue evaluation of a
    given population. Immersive working environments are created to avoid expensive
    physical mock-up in conventional evaluation methods.

  22. Performance evaluation of parallel manipulators for milling application.

    Authors: Damien Chablat, Sébastien Briot, Anatoly Pashkevich, Alexandr Klimchik
    Subjects: Robotics
    Abstract

    This paper focuses on the performance evaluation of the parallel manipulators
    for milling of composite materials. For this application the most significant
    performance measurements, which denote the ability of the manipulator for the
    machining are defined. In this case, optimal synthesis task is solved as a
    multicriterion optimization problem with respect to the geometric, kinematic,
    kinetostatic, elastostostatic, dynamic properties. It is shown that stiffness
    is an important performance factor.

  23. Stiffness Analysis of Parallel Manipulators with Preloaded Passive Joints.

    Authors: Damien Chablat, Anatoly Pashkevich, Alexandr Klimchik
    Subjects: Robotics
    Abstract

    The paper presents a methodology for the enhanced stiffness analysis of
    parallel manipulators with internal preloading in passive joints. It also takes
    into account influence of the external loading and allows computing both the
    non-linear "load-deflection" relation and the stiffness matrices for any given
    location of the end-platform or actuating drives.

  24. Discrete Partitioning and Coverage Control for Gossiping Robots.

    Authors: Francesco Bullo, Paolo Frasca, Ruggero Carli, Joseph W. Durham
    Subjects: Robotics
    Abstract

    We propose distributed algorithms to automatically deploy a group of mobile
    robots to partition and provide coverage of a non-convex environment. To handle
    arbitrary non-convex environments, we represent them as connected graphs. Our
    partitioning and coverage algorithm requires only short-range, unreliable
    pairwise "gossip" communication among the agents. The algorithm has two
    components: (1) a motion protocol to ensure that each robot communicates with
    its neighbors at least sporadically, and (2) a pairwise partitioning rule to
    update territory ownership whenever two robots communicate.

  25. A Scenario-Based Mobile Application for Robot-Assisted Smart Digital Homes.

    Authors: Ali Reza Manashty, Amir Rajabzadeh, Zahra Forootan Jahromi
    Subjects: Robotics
    Abstract

    Smart homes are becoming more popular, as every day a new home appliance can
    be digitally controlled. Smart Digital Homes are using a server to make
    interaction with all the possible devices in one place, on a computer or
    webpage. In this paper we designed and implemented a mobile application using
    Windows Mobile platform that can connect to the controlling server of a Smart
    Home and grants the access to the Smart Home devices and robots everywhere
    possible. UML diagrams are presented to illustrate the application design
    process.

  26. On reverse-engineering the KUKA Robot Language.

    Authors: Henrik Mühe, Andreas Angerer, Alwin Hoffmann, Wolfgang Reif
    Subjects: Robotics
    Abstract

    Most commercial manufacturers of industrial robots require their robots to be
    programmed in a proprietary language tailored to the domain - a typical
    domain-specific language (DSL). However, these languages oftentimes suffer from
    shortcomings such as controller-specific design, limited expressiveness and a
    lack of extensibility. For that reason, we developed the extensible Robotics
    API for programming industrial robots on top of a general-purpose language.
    Although being a very flexible approach to programming industrial robots, a
    fully-fledged language can be too complex for simple tasks.

  27. Improving the Quality of Non-Holonomic Motion by Hybridizing C-PRM Paths.

    Authors: Barak Raveh, Dan Halperin, Itamar Berger, Bosmat Eldar, Gal Zohar
    Subjects: Robotics
    Abstract

    Sampling-based motion planners are an effective means for generating
    collision-free motion paths. However, the quality of these motion paths, with
    respect to different quality measures such as path length, clearance,
    smoothness or energy, is often notoriously low. This problem is accentuated in
    the case of non-holonomic sampling-based motion planning, in which the space of
    feasible motion trajectories is restricted.

  28. A new closed-loop output error method for parameter identification of robot dynamics.

    Authors: Maxime Gautier, Alexandre Janot, Pierre-Olivier Vandanjon
    Subjects: Robotics
    Abstract

    Off-line robot dynamic identification methods are mostly based on the use of
    the inverse dynamic model, which is linear with respect to the dynamic
    parameters. This model is sampled while the robot is tracking reference
    trajectories that excite the system dynamics. This allows using linear
    least-squares techniques to estimate the parameters. The efficiency of this
    method has been proved through the experimental identification of many
    prototypes and industrial robots.

  29. Multi-Agent Deployment for Visibility Coverage in Polygonal Environments with Holes.

    Authors: Francesco Bullo, Karl J. Obermeyer, Anurag Ganguli
    Subjects: Robotics
    Abstract

    This article presents a distributed algorithm for a group of robotic agents
    with omnidirectional vision to deploy into nonconvex polygonal environments
    with holes. Agents begin deployment from a common point, possess no prior
    knowledge of the environment, and operate only under line-of-sight sensing and
    communication. The objective of the deployment is for the agents to achieve
    full visibility coverage of the environment while maintaining line-of-sight
    connectivity with each other.

  30. Formal-language-theoretic Optimal Path Planning For Accommodation of Amortized Uncertainties and Dynamic Effects.

    Authors: Ishanu Chattopadhyay, Asok Ray, Anthony Cascone
    Subjects: Robotics
    Abstract

    We report a globally-optimal approach to robotic path planning under
    uncertainty, based on the theory of quantitative measures of formal languages.
    A significant generalization to the language-measure-theoretic path planning
    algorithm $\nustar$ is presented that explicitly accounts for average dynamic
    uncertainties and estimation errors in plan execution.

  31. Optimal Path Planning under Temporal Logic Constraints.

    Authors: Stephen L. Smith, Jana Tůmová, Calin Belta, Daniela Rus
    Subjects: Robotics
    Abstract

    In this paper we present a method for automatically generating optimal robot
    trajectories satisfying high level mission specifications. The motion of the
    robot in the environment is modeled as a general transition system, enhanced
    with weighted transitions. The mission is specified by a general linear
    temporal logic formula. In addition, we require that an optimizing proposition
    must be repeatedly satisfied. The cost function that we seek to minimize is the
    maximum time between satisfying instances of the optimizing proposition.

  32. Online Event Segmentation in Active Perception using Adaptive Strong Anticipation.

    Authors: Bruno Nery, Rodrigo Ventura
    Subjects: Robotics
    Abstract

    Most cognitive architectures rely on discrete representation, both in space
    (e.g., objects) and in time (e.g., events). However, a robot interaction with
    the world is inherently continuous, both in space and in time. The segmentation
    of the stream of perceptual inputs a robot receives into discrete and
    meaningful events poses as a challenge in bridging the gap between internal
    cognitive representations, and the external world.

  33. Approximate Robotic Mapping from sonar data by modeling Perceptions with Antonyms.

    Authors: Sergio Guadarrama, Antonio Ruiz-Mayor
    Subjects: Robotics
    Abstract

    This work, inspired by the idea of "Computing with Words and Perceptions"
    proposed by Zadeh in 2001, focuses on how to transform measurements into
    perceptions for the problem of map building by Autonomous Mobile Robots. We
    propose to model the perceptions obtained from sonar-sensors as two grid maps:
    one for obstacles and another for empty spaces. The rules used to build and
    integrate these maps are expressed by linguistic descriptions and modeled by
    fuzzy rules.

  34. Fatigue evaluation in maintenance and assembly operations by digital human simulation.

    Authors: Damien Chablat, Wei Zhang, Liang Ma, Fouad Bennis, Bo Hu, François Guillaume
    Subjects: Robotics
    Abstract

    Virtual human techniques have been used a lot in industrial design in order
    to consider human factors and ergonomics as early as possible. The physical
    status (the physical capacity of virtual human) has been mostly treated as
    invariable in the current available human simulation tools, while indeed the
    physical capacity varies along time in an operation and the change of the
    physical capacity depends on the history of the work as well. Virtual Human
    Status is proposed in this paper in order to assess the difficulty of manual
    handling operations, especially from the physical perspective.

  35. Open-Ended Evolutionary Robotics: an Information Theoretic Approach.

    Authors: Marc Schoenauer, Pierre Delarboulas, Michèle Sebag
    Subjects: Robotics
    Abstract

    This paper is concerned with designing self-driven fitness functions for
    Embedded Evolutionary Robotics. The proposed approach considers the entropy of
    the sensori-motor stream generated by the robot controller. This entropy is
    computed using unsupervised learning; its maximization, achieved by an on-board
    evolutionary algorithm, implements a "curiosity instinct", favouring
    controllers visiting many diverse sensori-motor states (sms). Further, the set
    of sms discovered by an individual can be transmitted to its offspring, making
    a cultural evolution mode possible.

  36. Dynamic Motion Modelling for Legged Robots.

    Authors: Mark Edgington, Yohannes Kassahun, Frank Kirchner
    Subjects: Robotics
    Abstract

    An accurate motion model is an important component in modern-day robotic
    systems, but building such a model for a complex system often requires an
    appreciable amount of manual effort. In this paper we present a motion model
    representation, the Dynamic Gaussian Mixture Model (DGMM), that alleviates the
    need to manually design the form of a motion model, and provides a direct means
    of incorporating auxiliary sensory data into the model.

  37. Using vector divisions in solving linear complementarity problem.

    Authors: Youssef Elfoutayeni, Mohamed Khaladi
    Subjects: Robotics
    Abstract

    The linear complementarity problem is to find vector $z$ in $\mathrm{IR}^{n}$
    satisfying $z^{T}(Mz+q)=0$, $Mz+q\geqslant0,$ $z\geqslant0$, where $M$ as a
    matrix and $q$ as a vector, are given data; this problem becomes in present the
    subject of much important research because it arises in many areas and it
    includes important fields, we cite for example the linear and nonlinear
    programming, the convex quadratic programming and the variational inequalities
    problems, ...

  38. Fuzzy Logic of Speed and Steering Control System for Three Dimensional Line Following of an Autonomous Vehicle.

    Authors: Shailja Shukla, Mukesh Tiwari
    Subjects: Robotics
    Abstract

    ... This paper is to describe exploratory research on the design of a modular
    autonomous mobile robot controller. The controller incorporates a fuzzy logic
    [8] [9] approach for steering and speed control [37], a FL approach for
    ultrasound sensing and an overall expert system for guidance. The advantages of
    a modular system are related to portability and transportability, i.e. any
    vehicle can become autonomous with minimal modifications.

  39. Ball on a beam: stabilization under saturated input control with large basin of attraction.

    Authors: Yannick Aoustin, Alexander Formal'skii
    Subjects: Robotics
    Abstract

    This article is devoted to the stabilization of two underactuated planar
    systems, the well-known straight beam-and-ball system and an original circular
    beam-and-ball system. The feedback control for each system is designed, using
    the Jordan form of its model, linearized near the unstable equilibrium. The
    limits on the voltage, fed to the motor, are taken into account explicitly. The
    straight beam-and-ball system has one unstable mode in the motion near the
    equilibrium point. The proposed control law ensures that the basin of
    attraction coincides with the controllability domain.

  40. A Neuro-Fuzzy Multi Swarm FastSLAM Framework.

    Authors: R. Havangi, M. Teshnehlab, M. A. Nekoui
    Subjects: Robotics
    Abstract

    FastSLAM is a framework for simultaneous localization using a
    Rao-Blackwellized particle filter. In FastSLAM, particle filter is used for the
    mobile robot pose (position and orientation) estimation, and an Extended Kalman
    Filter (EKF) is used for the feature location's estimation. However, FastSLAM
    degenerates over time. This degeneracy is due to the fact that a particle set
    estimating the pose of the robot loses its diversity. One of the main reasons
    for loosing particle diversity in FastSLAM is sample impoverishment.

  41. Design of a Smart Unmanned Ground Vehicle for Hazardous Environments.

    Authors: Subhadip Basu, Saurav Chakraborty
    Subjects: Robotics
    Abstract

    A smart Unmanned Ground Vehicle (UGV) is designed and developed for some
    application specific missions to operate predominantly in hazardous
    environments. In our work, we have developed a small and lightweight vehicle to
    operate in general cross-country terrains in or without daylight. The UGV can
    send visual feedbacks to the operator at a remote location. Onboard infrared
    sensors can detect the obstacles around the UGV and sends signals to the
    operator.

  42. Cuspidal and Noncuspidal Robot Manipulators.

    Authors: Philippe Wenger
    Subjects: Robotics
    Abstract

    This article synthezises the most important results on the kinematics of
    cuspidal manipulators i.e. nonredundant manipulators that can change posture
    without meeting a singularity. The characteristic surfaces, the uniqueness
    domains and the regions of feasible paths in the workspace are defined. Then,
    several sufficient geometric conditions for a manipulator to be noncuspidal are
    enumerated and a general necessary and sufficient condition for a manipulator
    to be cuspidal is provided. An explicit DH-parameter-based condition for an
    orthogonal manipulator to be cuspidal is derived.

  43. Position Analysis of the RRP-3(SS) Multi-Loop Spatial Structure.

    Authors: Philippe Wenger, Carlo Innocenti
    Subjects: Robotics
    Abstract

    The paper presents the position analysis of a spatial structure composed of
    two platforms mutually connected by one RRP and three SS serial kinematic
    chains, where R, P, and S stand for revolute, prismatic, and spherical
    kinematic pair respectively. A set of three compatibility equations is laid
    down that, following algebraic elimination, results in a 28th-order univariate
    algebraic equation, which in turn provides the addressed problem with 28
    solutions in the complex domain.

  44. A Little More, a Lot Better: Improving Path Quality by a Simple Path Merging Algorithm.

    Authors: Barak Raveh, Angela Enosh, Dan Halperin
    Subjects: Robotics
    Abstract

    Sampling-based motion planners are effective means for generating
    collision-free motion paths. However, the quality of these motion paths is
    often notoriously low, especially in high-dimensional configuration spaces
    (with respect to quality measures such as path length, clearance, smoothness or
    energy). We introduce a simple and effective algorithm for merging an arbitrary
    number of input motion paths into a hybrid output path of superior quality,
    using a generalized formulation of path quality.

  45. Modeling and Application of Series Elastic Actuators for Force Control Multi Legged Robots.

    Authors: Arumugom.S, Muthuraman.S, Ponselvan.V
    Subjects: Robotics
    Abstract

    Series Elastic Actuators provide many benefits in force control of robots in
    unconstrained environments. These benefits include high force fidelity,
    extremely low impedance, low friction, and good force control bandwidth. Series
    Elastic Actuators employ a novel mechanical design architecture which goes
    against the common machine design principal of "stiffer is better". A compliant
    element is placed between the gear train and driven load to intentionally
    reduce the stiffness of the actuator.

  46. Nonlinear Effects in Stiffness Modeling of Robotic Manipulators.

    Authors: Damien Chablat, Anatoly Pashkevich, Alexandr Klimchik
    Subjects: Robotics
    Abstract

    The paper focuses on the enhanced stiffness modeling of robotic manipulators
    by taking into account influence of the external force/torque acting upon the
    end point. It implements the virtual joint technique that describes the
    compliance of manipulator elements by a set of localized six-dimensional
    springs separated by rigid links and perfect joints.

  47. Calibration of 3-d.o.f. Translational Parallel Manipulators Using Leg Observations.

    Authors: Damien Chablat, Philippe Wenger, Anatoly Pashkevich, Roman Gomolitsky
    Subjects: Robotics
    Abstract

    The paper proposes a novel approach for the geometrical model calibration of
    quasi-isotropic parallel kinematic mechanisms of the Orthoglide family. It is
    based on the observations of the manipulator leg parallelism during motions
    between the specific test postures and employs a low-cost measuring system
    composed of standard comparator indicators attached to the universal magnetic
    stands.

  48. On the characterization of the regions of feasible trajectories in the workspace of parallel manipulators.

    Authors: Damien Chablat, Philippe Wenger
    Subjects: Robotics
    Abstract

    It was shown recently that parallel manipulators with several inverse
    kinematic solutions have the ability to avoid parallel singularities [Chablat
    1998a] and self-collisions [Chablat 1998b] by choosing appropriate joint
    configurations for the legs. In effect, depending on the joint configurations
    of the legs, a given configuration of the end-effector may or may not be free
    of singularity and collision.

  49. Path placement optimization of manipulators based on energy consumption: application to the orthoglide 3-axis.

    Authors: Damien Chablat, Philippe Wenger, Stéphane Caro, Raza Ur-Rehman
    Subjects: Robotics
    Abstract

    This paper deals with the optimal path placement for a manipulator based on
    energy consumption. It proposes a methodology to determine the optimal location
    of a given test path within the workspace of a manipulator with minimal
    electric energy used by the actuators while taking into account the geometric,
    kinematic and dynamic constraints. The proposed methodology is applied to the
    Orthoglide~3-axis, a three-degree-of-freedom translational parallel kinematic
    machine (PKM), as an illustrative example.

  50. Singularity Analysis of Lower-Mobility Parallel Manipulators Using Grassmann-Cayley Algebra.

    Authors: Damien Chablat, Philippe Wenger, Daniel Kanaan, Stéphane Caro
    Subjects: Robotics
    Abstract

    This paper introduces a methodology to analyze geometrically the
    singularities of manipulators, of which legs apply both actuation forces and
    constraint moments to their moving platform. Lower-mobility parallel
    manipulators and parallel manipulators, of which some legs do not have any
    spherical joint, are such manipulators. The geometric conditions associated
    with the dependency of six Pl\"ucker vectors of finite lines or lines at
    infinity constituting the rows of the inverse Jacobian matrix are formulated
    using Grassmann-Cayley Algebra.

  51. D\'efinition d'une pi\`ece test pour la caract\'erisation d'une machine UGV.

    Authors: Laurent Tapie, Kwamiwi Mawussi
    Subjects: Robotics
    Abstract

    In several fields like aeronautics, die and automotive, the machining of the
    parts is done more and more on high speed machines tools. Today, the offer for
    purchasing these machine tools is very wide. This situation poses the problem
    of the judicious and objective choice meeting industrial needs that must be
    necessary well expressed. The choice remains difficult insofar as the technical
    data provided to the customers by the manufacturers of machine tools are
    insufficient as well quantitatively as qualitatively.

  52. Decomposition of forging dies for machining planning.

    Authors: Laurent Tapie, Kwamiwi Mawussi, Bernard Anselmetti
    Subjects: Robotics
    Abstract

    This paper will provide a method to decompose forging dies for machining
    planning in the case of high speed machining finishing operations. This method
    lies on a machining feature approach model presented in the following paper.
    The two main decomposition phases, called Basic Machining Features Extraction
    and Process Planning Generation, are presented. These two decomposition phases
    integrates machining resources models and expert machining knowledge to provide
    an outstanding process planning.

  53. Machining strategy choice: performance VIEWER.

    Authors: Laurent Tapie, Kwamiwi Mawussi, Bernard Anselmetti
    Subjects: Robotics
    Abstract

    Nowadays high speed machining (HSM) machine tool combines productivity and
    part quality. So mould and die maker invested in HSM. Die and mould features
    are more and more complex shaped. Thus, it is difficult to choose the best
    machining strategy according to part shape. Geometrical analysis of machining
    features is not sufficient to make an optimal choice. Some research show that
    security, technical, functional and economical constrains must be taken into
    account to elaborate a machining strategy.

  54. Decomposition of forging die for high speed machining.

    Authors: Laurent Tapie, Kwamiwi Mawussi
    Subjects: Robotics
    Abstract

    Today's forging die manufacturing process must be adapted to several
    evolutions in machining process generation: CAD/CAM models, CAM software
    solutions and High Speed Machining (HSM). In this context, the adequacy between
    die shape and HSM process is in the core of machining preparation and process
    planning approaches. This paper deals with an original approach of machining
    preparation integrating this adequacy in the main tasks carried out.

  55. Circular tests for HSM machine tools: Bore machining application.

    Authors: Laurent Tapie, Kwamiwi Mawussi, Bernard Anselmetti
    Subjects: Robotics
    Abstract

    Today's High-Speed Machining (HSM) machine tool combines productivity and
    part quality. The difficulty inherent in HSM operations lies in understanding
    the impact of machine tool behaviour on machining time and part quality.
    Analysis of some of the relevant ISO standards (230-1998, 10791-1998) and a
    complementary protocol for better understanding HSM technology are presented in
    the first part of this paper. These ISO standards are devoted to the procedures
    implemented in order to study the behavior of machine tool.

  56. Stiffness Analysis Of Multi-Chain Parallel Robotic Systems.

    Authors: Damien Chablat, Philippe Wenger, Anatoly Pashkevich, Alexandr Klimchik
    Subjects: Robotics
    Abstract

    The paper presents a new stiffness modelling method for multi-chain parallel
    robotic manipulators with flexible links and compliant actuating joints. In
    contrast to other works, the method involves a FEA-based link stiffness
    evaluation and employs a new solution strategy of the kinetostatic equations,
    which allows computing the stiffness matrix for singular postures and to take
    into account influence of the external forces.

  57. Kinematic calibration of Orthoglide-type mechanisms from observation of parallel leg motions.

    Authors: Damien Chablat, Philippe Wenger, Anatoly Pashkevich
    Subjects: Robotics
    Abstract

    The paper proposes a new calibration method for parallel manipulators that
    allows efficient identification of the joint offsets using observations of the
    manipulator leg parallelism with respect to the base surface. The method
    employs a simple and low-cost measuring system, which evaluates deviation of
    the leg location during motions that are assumed to preserve the leg
    parallelism for the nominal values of the manipulator parameters. Using the
    measured deviations, the developed algorithm estimates the joint offsets that
    are treated as the most essential parameters to be identified.

  58. Design of an ultrasound-guided robotic brachytherapy needle insertion system.

    Authors: Nikolai Hungr, Jocelyne Troccaz, Nabil Zemiti, Nathanael Tripodi
    Subjects: Robotics
    Abstract

    In this paper we describe a new robotic brachytherapy needle-insertion system
    that is designed to replace the template used in the manual technique. After a
    brief review of existing robotic systems, we describe the requirements that we
    based our design upon. A detailed description of the proposed system follows.
    Our design is capable of positioning and inclining a needle within the same
    workspace as the manual template. To help improve accuracy, the needle can be
    rotated about its axis during insertion into the prostate.

  59. Kinematic analysis of a class of analytic planar 3-RPR parallel manipulators.

    Authors: Damien Chablat, Philippe Wenger
    Subjects: Robotics
    Abstract

    A class of analytic planar 3-RPR manipulators is analyzed in this paper.
    These manipulators have congruent base and moving platforms and the moving
    platform is rotated of 180 deg about an axis in the plane. The forward
    kinematics is reduced to the solution of a 3rd-degree polynomial and a
    quadratic equation in sequence. The singularities are calculated and plotted in
    the joint space. The second-order singularities (cups points), which play an
    important role in non-singular change of assembly-mode motions, are also
    analyzed.

  60. On the optimal design of parallel robots taking into account their deformations and natural frequencies.

    Authors: Damien Chablat, Sébastien Briot, Anatoly Pashkevich
    Subjects: Robotics
    Abstract

    This paper discusses the utility of using simple stiffness and vibrations
    models, based on the Jacobian matrix of a manipulator and only the rigidity of
    the actuators, whenever its geometry is optimised. In many works, these
    simplified models are used to propose optimal design of robots. However, the
    elasticity of the drive system is often negligible in comparison with the
    elasticity of the elements, especially in applications where high dynamic
    performances are needed.

  61. The eel-like robot.

    Authors: Frédéric Boyer, Damien Chablat, Philippe Lemoine, Philippe Wenger
    Subjects: Robotics
    Abstract

    The aim of this project is to design, study and build an "eel-like robot"
    prototype able to swim in three dimensions. The study is based on the analysis
    of eel swimming and results in the realization of a prototype with 12
    vertebrae, a skin and a head with two fins. To reach these objectives, a
    multidisciplinary group of teams and laboratories has been formed in the
    framework of two French projects.

Syndicate content