Dedicated and industrial robotic arms used as force feedback telerobots at the AREVA-La Hague recycling plant

ISBN: 978-1-4244-6635-1/10International audienceCEA LIST and AREVA have been developing remote operations devices, also called telerobotics for 15 years. These tools were designed for interventions in the AREVA nuclear spent fuel facilities hot cells. From these 15 years of joint research and development, several technological bricks have been industrialized and used at the AREVA La Hague facilities. This article presents some of these bricks and their industrial developments. The “TAO2000” CEA LIST telerobotics generic software controller will be first discussed. This controller has been used to teleoperate dedicated slave arms like the MT200 TAO (an evolution of the conventional wall-transmission mechanical telemanipulator (MSM)) as well as industrial robotic arms like the Stäubli RX robots. Both the MT200 TAO and Stäubli RX TAO telerobotics systems provide force-feedback and are now ready to be used as telemaintenance tools at the AREVA La Hague facilities. Two recent maintenance operations using these tools will be detailed at the end of this pape

Development and Validation of a Risk Score for Chronic Kidney Disease in HIV Infection Using Prospective Cohort Data from the D:A:D Study

Ristola M. on työryhmien DAD Study Grp ; Royal Free Hosp Clin Cohort ; INSIGHT Study Grp ; SMART Study Grp ; ESPRIT Study Grp jäsen.Background Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice. Methods and Findings A total of 17,954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with >= 3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR > 60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR In the D:A:D study, 641 individuals developed CKD during 103,185 person-years of follow-up (PYFU; incidence 6.2/1,000 PYFU, 95% CI 5.7-6.7; median follow-up 6.1 y, range 0.3-9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was -2 (interquartile range -4 to 2). There was a 1: 393 chance of developing CKD in the next 5 y in the low risk group (risk score = 5, 505 events), respectively. Number needed to harm (NNTH) at 5 y when starting unboosted atazanavir or lopinavir/ritonavir among those with a low risk score was 1,702 (95% CI 1,166-3,367); NNTH was 202 (95% CI 159-278) and 21 (95% CI 19-23), respectively, for those with a medium and high risk score. NNTH was 739 (95% CI 506-1462), 88 (95% CI 69-121), and 9 (95% CI 8-10) for those with a low, medium, and high risk score, respectively, starting tenofovir, atazanavir/ritonavir, or another boosted protease inhibitor. The Royal Free Hospital Clinic Cohort included 2,548 individuals, of whom 94 individuals developed CKD (3.7%) during 18,376 PYFU (median follow-up 7.4 y, range 0.3-12.7 y). Of 2,013 individuals included from the SMART/ESPRIT control arms, 32 individuals developed CKD (1.6%) during 8,452 PYFU (median follow-up 4.1 y, range 0.6-8.1 y). External validation showed that the risk score predicted well in these cohorts. Limitations of this study included limited data on race and no information on proteinuria. Conclusions Both traditional and HIV-related risk factors were predictive of CKD. These factors were used to develop a risk score for CKD in HIV infection, externally validated, that has direct clinical relevance for patients and clinicians to weigh the benefits of certain antiretrovirals against the risk of CKD and to identify those at greatest risk of CKD.Peer reviewe

ETUDE ET CONCEPTION DE LA COMMANDE EN EFFORT D'UN TELEMANIPULATEUR EQUIPE D'UN CAPTEUR D'EFFORTS A SA BASE ET A SON EXTREMITE

LA SENSIBILITE DU RETOUR D'EFFORTS DES SYSTEMES DE TELEMANIPULATION EST LIEE A LA QUALITE DE LA REVERSIBILITE DE SES ORGANES DE COMMANDE MAITRE ET ESCLAVE. DANS CETTE THESE, NOUS PROPOSONS DE REVERSIBILISER UN MANIPULATEUR ESCLAVE INDUSTRIEL EN UTILISANT UN CAPTEUR D'EFFORTS PLACE SOUS SA BASE ET/OU UN CAPTEUR D'EFFORTS MONTE SUR SON ORGANE TERMINAL (CET). TOUT D'ABORD, NOUS DONNONS UN ESTIMATEUR DES COUPLES ARTICULAIRES, LINEAIRE EN LES PARAMETRES DYNAMIQUES, UTILISANT LA MESURE ISSUE DU CAPTEUR D'EFFORTS EN BASE (CEB). UNE VERSION DE CET ESTIMATEUR NE NECESSITANT PAS LA MESURE EXPLICITE DE L'ACCELERATION EST EGALEMENT CALCULEE. PUIS, NOUS PROPOSONS UNE METHODOLOGIE D'IDENTIFICATION DES PARAMETRES DYNAMIQUES D'UN ROBOT, A PARTIR DE LA MESURE ISSUE DU CEB. UNE ETUDE CONCERNANT L'IDENTIFIABILITE DES INERTIES DES ROTORS MOTEURS EST PRESENTEE. PAR AILLEURS, LA PASSIVITE ETANT INDISPENSABLE A LA STABILITE DU SYSTEME DE TELEMANIPULATION, NOUS PRESENTONS DANS CETTE THESE, UNE ANALYSE DETAILLEE DES DIFFERENCES STRUCTURELLES ENTRE LES COMMANDES UTILISANT UN CEB ET/OU UN CET. NOUS EN DEDUISONS UNE COMMANDE ASSURANT LA STABILITE DU SYSTEME COUPLE, AINSI QU'UNE COMPARAISON THEORIQUE DES PERFORMANCES DES DEUX SOLUTIONS. CONCERNANT LA MISE EN UVRE DE CES SOLUTIONS, NOUS PROPOSONS UNE ADAPTATION D'UNE METHODE DE REGLAGE FREQUENTIELLE DE FACON A OBTENIR UN REGLAGE POSSEDANT DES MARGES SATISFAISANTES POUR L'ENSEMBLE DES CONFIGURATIONS DE TRAVAIL DU ROBOT. CETTE MEME METHODE ETANT UTILISEE POUR LE REGLAGE EN EFFORT ET EN POSITION, AVEC LE CEB ET AVEC LE CET, NOUS OBTENONS UNE COMPARAISON EXPERIMENTALE RIGOUREUSE DES PERFORMANCES DES DEUX SOLUTIONS MATERIELLES. ENFIN, NOUS PROPOSONS D'UTILISER LA COMBINAISON CEB/CET POUR SECURISER LES SYSTEMES DE TELEMANIPULATION, EN PROPOSANT UN RETOUR D'EFFORTS A L'OPERATEUR LORS DE CONTACTS ENTRE L'ENVIRONNEMENT DE TRAVAIL, L'ORGANE TERMINAL, ET/OU CERTAINS CORPS DU ROBOT.NANTES-Ecole Centrale (441092306) / SudocNANTES-BU Sciences (441092104) / SudocSudocFranceF

Controller design of a robotic assistant for the transport of large and fragile objects

International audienceThis paper deals with the design of a robotic assistant for the transport of large and fragile objects. We propose a new collaborative robotic controller that fulfills the main requirements of co-transportation tasks of large and fragile objects: to execute any trajectory in a collaborative mode while minimizing the stress applied on the object by both partners in order to avoid damaging it. This controller prevents the robot from applying torques on the object while maintaining a desired orientation of the object along the transport trajectory in order to follow the operator. An original feature of our approach is to care about torques applied by both partners (not only by operator) during any co-manipulation trajectory execution. It leads to a novel outcome: the minimization of stress applied by both partners on a large and fragile object during its transport on any trajectory. We demonstrate the effectiveness of this approach in a collaborative transportation task

Underwater pre-touch based on artificial electric sense

International audienceThis article exploits a bio-inspired sensor technology named artificial electric-sense to emulate underwater pre-touch. The sensor is considered as an electric finger remote-controlled by an operator to follow the boundaries of objects. Using electric measurements only, the approach feeds back pre-touch forces and torques to the operator through an haptic interface. These forces and torques are generated by a set of virtual electric charges and dipoles arranged on the probe and reacting in the electric field reflected by the objects. This model of emulated forces is passive and guarantees the stability of a position-position haptic feedback loop. The whole approach is assessed through a set of experiments carried out on a Cartesian slave robot coupled to an haptic interface. The obtained results show the feasibility of the concept and its robustness to different configuration of objects. Such an electro-haptic feedback opens new perspectives in both electric field sensing and underwater robotics

Controlling an upper-limb exoskeleton by EMG signal while carrying unknown load

International audienceImplementing an intuitive control law for an upper-limb exoskeleton dedicated to force augmentation is a challenging issue in the field of human-robot collaboration. The aim of this study is to design an innovative approach to assist carrying an unknown load. The method is based on user's intentions estimated through a wireless EMG armband allowing movement direction and intensity estimation along 1 Degree of Freedom. This control law aimed to behave like a gravity compensation except that the mass of the load does not need to be known. The proposed approach was tested by 10 participants on a lifting task with a single Degree of Freedom upper-limb exoskeleton. Participants performed it in three different conditions : without assistance, with an exact gravity compensation and with the proposed method based on EMG armband (Myo Armband). The evaluation of the efficiency of the assistance was based on EMG signals captured on seven muscles (objective indicator) and a questionnaire (subjective indicator). Results showed a statically significant reduction of mean activity of the biceps, erector spinae and deltoid by 20% ± 14, 18% ± 12 and 25% ± 16 respectively while comparing the proposed method with no assistance. In addition, similar muscle activities were found both in the proposed method and the traditional gravity compensation. Subjective evaluation showed better precision, efficiency and responsiveness of the proposed method compared to the traditional one

Optimal docking pose and tactile hook-localisation strategy for AUV intervention: The DIFIS deployment case

The DIFIS project has proposed a new solution for the immediate intervention directly on tanker wrecks so as to contain any leakages and prevent eventual pollution. The method could be extended also to oil well-blow-out cases such as the recent accident in the Gulf of Mexico. The DIFIS deployment typically requires the use of ROVs and dedicated dynamic-positioning ships that increase the cost significantly and make the operations weather-dependent. Eventual AUV use would result in much more efficient and flexible deployment procedures. The scenario studied here consists of a hook-grasping task that is part of the DIFIS mooring procedure. The overall objective is to automate certain processes enabling the use of AUVs or, at least, enhancing the currently foreseen ROV operations. A two-step method is presented consisting of a genetic algorithm for the determination of the optimum docking pose for the vehicle, and a particle filter algorithm that runs on a later stage for the tactile localisation of the hook. The method proposed is rather generic and can be extended to several steps of the DIFIS Deployment procedure, or even to other AUV intervention missions in a semi-structured environment. Results from the two algorithms are also presented and discussed.JRC.G.7-Digital Citizen Securit

Interacting with a "transparent" upper-limb exoskeleton: a human motor control approach

International audienceEstablishing a symbiotic relationship between a human and a exoskeleton is the end goal in many applications in order to provide benefits to the user. However, the literature focusing on the human side of human-exoskeleton interaction has remained less exhaustive than the literature focusing on the design (hardware/software) of the exoskeleton device itself. It is, though, essential to understand how a human adapts his motor control when interacting with an exoskeleton. Motor adaptation is an implicit process carried out by the central nervous system when the body encounters a perturbation, a paradigm that has been extensively studied in the field of human motor control research. When wearing an exoskeleton, even "as-transparent-as-possible", contact/interaction forces may impact well-known motor control laws in a way that may be detrimental to the user, and even compromise usability in real applications. The present paper investigates how interaction with a backdrivable upper-limb exoskeleton (ABLE) set in "transparent" mode of control affects the kinematics/dynamics of human movement in a simple task. We find that important motor control features are preserved when moving with ABLE but an overall movement slowness occurs, likely as a response to increased inertia according to optimal control simulations. Such a human motor control approach illustrates one possible way to assess the degree of symbiosis between human and exoskeleton, i.e. by grounding on well-known findings in motor control research

Controlling an Exoskeleton with EMG Signal to Assist Load Carrying: A Personalized Calibration

978-1-7281-3983-8/19International audienceImplementing an intuitive control law for an upper-limb exoskeleton to perform force augmentation is a challenging issue in the field of human-robot collaboration. The aim of this study is to design an innovative approach to calibrate electromyo-graphy (EMG) data in order to detect the intention to lift or put down a charge while wearing an upper-limb exoskeleton. Based on a low-cost EMG sensor bracelet placed around the arm (Myo armband, Thalmics Lab, Ontario), a subject-specific mapping procedure is implemented to discriminate motion intentions during lifting tasks with a 1-DoF upper-limb exoskeleton. The processing is divided into two main parts: (i) direction estimation with an artificial neural network, and (ii) a model-based intensity prediction. The mapping procedure has been tested on 7 healthy participants with a precision of 96.9 $\pm$ 3.1% for the classification and a RMS Error of 3.8 $\pm$ 0.8$N$ at the end effector. This study opens up the way for fast-deployment applications involving exoskeletons or cobots

Personalizing the control law of an upper-limb exoskeleton using EMG signal

Abstract Implementing an intuitive control law for an upper-limb exoskeleton dedicated to force augmentation is a challenging issue in the field of human-robot collaboration. The goal of this study is to adapt an EMG-based control system to a user based on individual caracteristics. To this aim, a method has been designed to tune the parameters of control using objective criteria, improving user’s feedback. The user’s response time is used as an objective value to adapt the gain of the controller. The proposed approach was tested on 10 participants during a lifting task. Two different conditions have been used to control the exoskeleton: with a generic gain and with a personalized gain. EMG signals was captured on five muscles to evaluate the efficiency of the conditions and the user’s adaptation. Results showed a statistically significant reduction of mean muscle activity of the deltoid between the beginning and the end of each situation (28.6 ± 13.5% to 17.2 ± 7.3% of Relative Maximal Contraction for the generic gain and from 24.9 ± 8.5% to 18.0 ± 6.8% of Relative Maximal Contraction for the personalized gain). When focusing on the first assisted movements, the personalized gain induced a mean activity of the deltoïd significantly lower (29.0 ± 8.0% of Relative Maximal Contraction and 37.4 ± 9.5% of Relative Maximal Contraction, respectively). Subjective evaluation showed that the system with a personalized gain was perceived as more intuitive, and required less concentration when compared to the system with a generic gain