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Sample records for electro-hydraulic manipulator arm

  1. Modeling and stability of electro-hydraulic servo of hydraulic excavator

    Science.gov (United States)

    Jia, Wenhua; Yin, Chenbo; Li, Guo; Sun, Menghui

    2017-11-01

    The condition of the hydraulic excavator is complicated and the working environment is bad. The safety and stability of the control system is influenced by the external factors. This paper selects hydraulic excavator electro-hydraulic servo system as the research object. A mathematical model and simulation model using AMESIM of servo system is established. Then the pressure and flow characteristics are analyzed. The design and optimization of electro-hydraulic servo system and its application in engineering machinery is provided.

  2. Technology and control for hydraulic manipulators

    International Nuclear Information System (INIS)

    Measson, Y.; David, O.; Louveau, F.; Friconneau, J.P.

    2003-01-01

    Hydraulic manipulators are candidate for fusion reactor maintenance. Their main advantages are their large payload with respect to volume and mass, their reliability and their robustness. However, due to their force control limitations, they are disqualified for precise manipulation and are dangerous for the environment and themselves in case of unexpected collision. CEA, in collaboration with CYBERNETIX and IFREMER has developed the advanced hydraulic robot MAESTRO. Force and hybrid control has been developed in order to avoid the previous problems. Using 'pressure' control servo-valve instead of the standard 'flow' control servo-valve (standard configuration of the MAESTRO) makes a real simplification of the control loop. No more pressure sensors are needed for monitoring the hydraulic joint in force control mode and using this kind of valves makes big safety improvements. The French company IN-LHC, designed and manufactured a prototype of servo-valve that fits the performances and space constraints of the Maestro arm. A characterisation of this new product was made on a mock-up and a set of these prototypes integrated in the Maestro slave-arm. A comparison between the two actuating technologies was made and showed that the performances of the pressure servo-valves make it applicable to general application

  3. Parallelogram mechanisms for mine manipulator arms

    Energy Technology Data Exchange (ETDEWEB)

    Yoncheva, N

    1983-01-01

    Kinematic equations are written for the mechanism of a manipulator arm which is used as the operational element of a basic machine and is shaped like a parallelogram. The drive is accomplished using a hydraulic cylinder. A transfer functions method is used to acquire kinematic equations of the final shifts and equations for determining accelerations.

  4. Hydraulic manipulator research at ORNL

    International Nuclear Information System (INIS)

    Kress, R.L.; Jansen, J.F.; Love, L.J.

    1997-01-01

    Recently, task requirements have dictated that manipulator payload capacity increase to accommodate greater payloads, greater manipulator length, and larger environmental interaction forces. General tasks such as waste storage tank cleanup and facility dismantlement and decommissioning require manipulator life capacities in the range of hundreds of pounds rather than tens of pounds. To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned once again to hydraulics as a means of actuation. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem), sophisticated modeling, analysis, and control experiments are usually needed. Oak Ridge National Laboratory (ORNL) has a history of projects that incorporate hydraulics technology, including mobile robots, teleoperated manipulators, and full-scale construction equipment. In addition, to support the development and deployment of new hydraulic manipulators, ORNL has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The purpose of this article is to describe the past hydraulic manipulator developments and current hydraulic manipulator research capabilities at ORNL. Included are example experimental results from ORNL's flexible/prismatic test stand

  5. Hydraulic manipulator research at ORNL

    Energy Technology Data Exchange (ETDEWEB)

    Kress, R.L.; Jansen, J.F. [Oak Ridge National Lab., TN (United States); Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States)

    1997-03-01

    Recently, task requirements have dictated that manipulator payload capacity increase to accommodate greater payloads, greater manipulator length, and larger environmental interaction forces. General tasks such as waste storage tank cleanup and facility dismantlement and decommissioning require manipulator life capacities in the range of hundreds of pounds rather than tens of pounds. To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned once again to hydraulics as a means of actuation. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem), sophisticated modeling, analysis, and control experiments are usually needed. Oak Ridge National Laboratory (ORNL) has a history of projects that incorporate hydraulics technology, including mobile robots, teleoperated manipulators, and full-scale construction equipment. In addition, to support the development and deployment of new hydraulic manipulators, ORNL has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The purpose of this article is to describe the past hydraulic manipulator developments and current hydraulic manipulator research capabilities at ORNL. Included are example experimental results from ORNL`s flexible/prismatic test stand.

  6. MAESTRO, a hydraulic manipulator for maintenance and decommissioning applications

    International Nuclear Information System (INIS)

    Olivier David; Yvan Measson; Catherine Bidard; Christine Libersa

    2006-01-01

    Compared to electric technology payload of hydraulic manipulators is very high with respect to their volume and mass. However, due to their force control limitations they were usually disqualified for precise manipulation. CEA, in collaboration with CYBERNETIX developed a complete remote handling system around the advanced hydraulic robotic arm MAESTRO. Requirements and specifications of the system were defined according to the needs of decommissioning activities in existing nuclear facilities and maintenance scenarios of the next step fusion reactor ITER. Using TAO2000 CEA controller, CEA developed specific force control loops to improve the performances of the manipulator and reach a level where the MAESTRO can be used like a traditional tele-operation master/slave system with force feedback. The complete system is composed of a 2 m long 100 kg payload 6 degrees of freedom slave hydraulic manipulator. The manipulator is mounted on an embedded unit made of a 210 bars hydraulic power pack and a 10 kGy rad hardened slave controller. The master station is made of the new generation Virtuose V6D-40-40 master arm with its TAO2000 controller. The graphical supervisor Magritte gives the operator an additional interface to manage and monitor the system. Repetitive tasks like tool picking can therefore be left to the system while the operator keeps his concentration on the main task. Thanks to the collision detection algorithm, Magritte warns the operator when the tool or any part of the Maestro arm comes too close to a delicate unit. Operational experience gained through test campaigns was gathered in an upgrade study to propose a new version of the manipulator that successfully ran through a 1000 hour endurance test. Rad-hardened components were selected and tested in nuclear facilities. Attention was paid to provide a design in which contamination is easily removed and to ease the maintenance when performed by an operator in suit. To be quickly adapted to new tasks, the

  7. Robust Hinfinity position control synthesis of an electro-hydraulic servo system.

    Science.gov (United States)

    Milić, Vladimir; Situm, Zeljko; Essert, Mario

    2010-10-01

    This paper focuses on the use of the techniques based on linear matrix inequalities for robust H(infinity) position control synthesis of an electro-hydraulic servo system. A nonlinear dynamic model of the hydraulic cylindrical actuator with a proportional valve has been developed. For the purpose of the feedback control an uncertain linearized mathematical model of the system has been derived. The structured (parametric) perturbations in the electro-hydraulic coefficients are taken into account. H(infinity) controller extended with an integral action is proposed. To estimate internal states of the electro-hydraulic servo system an observer is designed. Developed control algorithms have been tested experimentally in the laboratory model of an electro-hydraulic servo system. Copyright © 2010 ISA. Published by Elsevier Ltd. All rights reserved.

  8. Powered manipulator control arm

    International Nuclear Information System (INIS)

    Le Mouee, Theodore; Vertut, Jean; Marchal, Paul; Germon, J.C.; Petit, Michel

    1975-01-01

    A remote operated control arm for powered manipulators is described. It includes an assembly allowing several movements with position sensors for each movement. The number of possible arm movements equals the number of possible manipulator movements. The control systems may be interrupted as required. One part of the arm is fitted with a system to lock it with respect to another part of the arm without affecting the other movements, so long as the positions of the manipulator and the arm have not been brought into complete coincidence. With this system the locking can be ended when complete concordance is achieved [fr

  9. Research Based on AMESim of Electro-hydraulic Servo Loading System

    Science.gov (United States)

    Li, Jinlong; Hu, Zhiyong

    2017-09-01

    Electro-hydraulic servo loading system is a subject studied by many scholars in the field of simulation and control at home and abroad. The electro-hydraulic servo loading system is a loading device simulation of stress objects by aerodynamic moment and other force in the process of movement, its function is all kinds of gas in the lab condition to analyze stress under dynamic load of objects. The purpose of this paper is the design of AMESim electro-hydraulic servo system, PID control technology is used to configure the parameters of the control system, complete the loading process under different conditions, the optimal design parameters, optimization of dynamic performance of the loading system.

  10. Highly reliable electro-hydraulic control system

    International Nuclear Information System (INIS)

    Mande, Morima; Hiyama, Hiroshi; Takahashi, Makoto

    1984-01-01

    The unscheduled shutdown of nuclear power stations disturbs power system, and exerts large influence on power generation cost due to the lowering of capacity ratio; therefore, high reliability is required for the control system of nuclear power stations. Toshiba Corp. has exerted effort to improve the reliability of the control system of power stations, and in this report, the electro-hydraulic control system for the turbines of nuclear power stations is described. The main functions of the electro-hydraulic control system are the control of main steam pressure with steam regulation valves and turbine bypass valves, the control of turbine speed and load, the prevention of turbine overspeed, the protection of turbines and so on. The system is composed of pressure sensors and a speed sensor, the control board containing the electronic circuits for control computation and protective sequence, the oil cylinders, servo valves and opening detectors of the valves for control, a high pressure oil hydraulic machine and piping, the operating panel and so on. The main features are the adoption of tripling intermediate value selection method, the multiplying of protection sensors and the adoption of 2 out of 3 trip logic, the multiplying of power sources, the improvement of the reliability of electronic circuit hardware and oil hydraulic system. (Kako, I.)

  11. Comparative analysis of hydraulic crane-manipulating installations transport and technological machines and industrial robots hydraulic manipulators

    Directory of Open Access Journals (Sweden)

    Lagerev I.A.

    2016-09-01

    Full Text Available The article presents results of comparative analysis of hydraulic crane-manipulator installations of mobile transport and technological machines and hydraulic manipulators of industrial robots. The comparative analysis is based on consid-eration of a wide range of types and sizes indicated technical devices of both domestic and foreign production: 1580 structures of cranes and more than 450 structures of industrial robots. It was performed in the following areas: func-tional purpose and basic technical characteristics; a design; the loading conditions of the model and failures in operation process; approaches to the design, calculation methods and mathematical modeling. The conclusions about the degree of similarity and the degree of difference hydraulic crane-manipulator installations of transport and technological ma-chines and hydraulic industrial robot manipulators from the standpoint of their design and modeling occurring in them during operation of dynamic and structural processes.

  12. Hydraulic manipulator

    International Nuclear Information System (INIS)

    Sinha, A.K.; Srikrishnamurty, G.

    1990-01-01

    Successful operation of nuclear plant is largely dependent on safe handling of radio-active material. In order to reduce this handling problem and minimise the exposure of radiation, various handling equipment and manipulators have been developed according to the requirements. Manufacture of nuclear fuel, which is the most important part of the nuclear industry, involves handling of uranium ingots weighing approximately 250 kg. This paper describes a specially designed hydraulic manipulator for handling of the ingots in a limited space. It was designed to grab and handle the ingots in any position. This has following drive motions: (1)gripping and releasing, (2)lifting and lowering (z-motion), (3)rotation about the horizontal axis (azimuth drive), (4)rotation about the job axis, and (5)rotation about the vertical axis. For horizontal motion (X and Y axis motion) this equipment is mounted on a motorised trolley, so that it can move inside the workshop. For all drives except the rotation about the job axis, hydraulic cylinders have been used with a battery operated power pack. Trolley drive is also given power from same battery. This paper describes the design aspects of this manipulator. (author). 4 figs

  13. Knowledge-based Adaptive Tracking Control of Electro-hydraulic Actuator Systems

    DEFF Research Database (Denmark)

    Hansen, Poul Erik

    1997-01-01

    The paper deal with intelligent motion control and electro-hydraulic actuator systems for multiaxis machynes and robots.The research results are from the IMCIA research Programme supported by the Danish Technical Research Council, STVF.......The paper deal with intelligent motion control and electro-hydraulic actuator systems for multiaxis machynes and robots.The research results are from the IMCIA research Programme supported by the Danish Technical Research Council, STVF....

  14. Hybrid Robust Control Law with Disturbance Observer for High-Frequency Response Electro-Hydraulic Servo Loading System

    Directory of Open Access Journals (Sweden)

    Zhiqing Sheng

    2016-04-01

    Full Text Available Addressing the simulating issue of the helicopter-manipulating booster aerodynamic load with high-frequency dynamic load superimposed on a large static load, this paper studies the design of the robust controller for the electro-hydraulic loading system to realize the simulation of this kind of load. Firstly, the equivalent linear model of the electro-hydraulic loading system under assumed parameter uncertainty is established. Then, a hybrid control scheme is proposed for the loading system. This control scheme consists of a constant velocity feed-forward compensator, a robust inner loop compensator based on disturbance observer and a robust outer loop feedback controller. The constant velocity compensator eliminates most of the extraneous force at first, and then the double-loop cascade composition control strategy is employed to design the compensated system. The disturbance observer–based inner loop compensator further restrains the disturbances including the remaining extraneous force, and makes the actual plant tracking a nominal model approximately in a certain frequency range. The robust outer loop controller achieves the desired force-tracking performance, and guarantees system robustness in the high frequency region. The optimized low-pass filter Q(s is designed by using the H∞ mixed sensitivity optimization method. The simulation results show that the proposed hybrid control scheme and controller can effectively suppress the extraneous force and improve the robustness of the electro-hydraulic loading system.

  15. Design of the Driving and Clamp Rotation Hydraulic Control System for the Heavy Load Forging Manipulator

    Directory of Open Access Journals (Sweden)

    Li Geqiang

    2015-01-01

    Full Text Available The manipulator was equipped with full hydraulic drive. We designed the hydraulic systems for the driving and clamping rotation. We used a fuzzy PID control strategy to design the electro-hydraulic proportional control system. We built a united simulation model based on the co-simulation of MATLAB/Simulink and AMEsim. A mathematical model of the system was also established. We did separate simulations of the system’s dynamic characteristics for fast forging and normal forging working conditions. The parameters were optimized. The field test shows that the steady-state error of the hydraulic system is small and the system response is fast. The system’s rapid response speed, high precision, and stability under heavy load were realized.

  16. Modelling and LPV control of an electro-hydraulic servo system

    NARCIS (Netherlands)

    Naus, G.J.L.; Wijnheijmer, F.P.; Post, W.J.A.E.M.; Steinbuch, M.; Teerhuis, A.P.

    2006-01-01

    This paper aims to show the modelling and control of an hydraulic servo system, targeting at frequency domain based controller design and the implementation of a LPV controller. The actual set-up consists of a mass, moved by a hydraulic cylinder and an electro-hydraulic servo valve. A nonlinear

  17. Precision Force Control for an Electro-Hydraulic Press Machine

    Directory of Open Access Journals (Sweden)

    Hong-Ming Chen

    2014-08-01

    Full Text Available This thesis is primarily intended to design a PC-based control system to control the force of an electro-hydraulic servo press system for implementing precision force control. The main feature is to develop a composite control by using the relief valve and the flow servo valve. Using feedback from a force sensor, a fuzzy controller was designed with LabVIEW software as the system control core for achieving a precision force control for the hydraulic cylinder on its travel and output. The weakness of hydraulic systems is that hydraulic oil is compressible and prone to leaking, and its characteristics can vary with oil temperature, thus making it difficult for a general linear controller to achieve accurate control. Therefore, a fuzzy controller was designed with LabVIEW along with a NI-PCI_6221 interface card and a load cell to control the servo valve flow and the relief valve to control the pressure source. The testing results indicate that accurate force control output of an electro-hydraulic servo press system can be obtained.

  18. Design of a Novel Electro-hydraulic Drive Downhole Tractor

    Science.gov (United States)

    Fang, Delei; Shang, Jianzhong; Yang, Junhong; Wang, Zhuo; Wu, Wei

    2018-02-01

    In order to improve the traction ability and the work efficiency of downhole tractor in oil field, a novel electro-hydraulic drive downhole tractor was designed. The tractor’s supporting mechanism and moving mechanism were analyzed based on the tractor mechanical structure. Through the introduction of hydraulic system, the hydraulic drive mechanism and the implementation process were researched. Based on software, analysis of tractor hydraulic drive characteristic and movement performance were simulated, which provide theoretical basis for the development of tractor prototype.

  19. Nonlinear Control of Hydraulic Manipulator for Decommissioning Nuclear Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myoung-Ho; Lee, Sung-Uk; Kim, Chang-Hoi; Choi, Byung-Seon; Moon, Jei-Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    Robot technique is need to decommission nuclear reactor because of high radiation environment. Especially, Manipulator systems are useful for dismantling complex structure in a nuclear facility. In addition, Hydraulic system is applied to handle heavy duty object. Since hydraulic system can demonstrate high power. The manipulator with hydraulic power is already developed. To solve this problem, various nonlinear control method includes acceleration control. But, it is difficult because acceleration value is highly noisy. In this paper, the nonlinear control algorithm without acceleration control is studied. To verify, the hydraulic manipulator model had been developed. Furthermore, the numerical simulation is carried out. The nonlinear control without acceleration parameter method is developed for hydraulic manipulator. To verify control algorithm, the manipulator is modeled by MBD and the hydraulic servo system is also derived. In addition, the numerical simulation is also carried out. Especially, PID gain is determined though TDC algorithm. In the result of numerical simulation, tracking performance is good without acceleration control. Thus, the PID though TDC with SMC is good for hydraulic manipulator control.

  20. Nonlinear Control of Hydraulic Manipulator for Decommissioning Nuclear Reactor

    International Nuclear Information System (INIS)

    Kim, Myoung-Ho; Lee, Sung-Uk; Kim, Chang-Hoi; Choi, Byung-Seon; Moon, Jei-Kwon

    2016-01-01

    Robot technique is need to decommission nuclear reactor because of high radiation environment. Especially, Manipulator systems are useful for dismantling complex structure in a nuclear facility. In addition, Hydraulic system is applied to handle heavy duty object. Since hydraulic system can demonstrate high power. The manipulator with hydraulic power is already developed. To solve this problem, various nonlinear control method includes acceleration control. But, it is difficult because acceleration value is highly noisy. In this paper, the nonlinear control algorithm without acceleration control is studied. To verify, the hydraulic manipulator model had been developed. Furthermore, the numerical simulation is carried out. The nonlinear control without acceleration parameter method is developed for hydraulic manipulator. To verify control algorithm, the manipulator is modeled by MBD and the hydraulic servo system is also derived. In addition, the numerical simulation is also carried out. Especially, PID gain is determined though TDC algorithm. In the result of numerical simulation, tracking performance is good without acceleration control. Thus, the PID though TDC with SMC is good for hydraulic manipulator control

  1. Robust H(∞) positional control of 2-DOF robotic arm driven by electro-hydraulic servo system.

    Science.gov (United States)

    Guo, Qing; Yu, Tian; Jiang, Dan

    2015-11-01

    In this paper an H∞ positional feedback controller is developed to improve the robust performance under structural and parametric uncertainty disturbance in electro-hydraulic servo system (EHSS). The robust control model is described as the linear state-space equation by upper linear fractional transformation. According to the solution of H∞ sub-optimal control problem, the robust controller is designed and simplified to lower order linear model which is easily realized in EHSS. The simulation and experimental results can validate the robustness of this proposed method. The comparison result with PI control shows that the robust controller is suitable for this EHSS under the critical condition where the desired system bandwidth is higher and the external load of the hydraulic actuator is closed to its limited capability. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  2. Hydraulic manipulator design, analysis, and control at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Kress, R.L.; Jansen, J.F. [Oak Ridge National Lab., TN (United States). Robotics and Process Systems Div.; Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States); Basher, A.M.H. [South Carolina State Univ., Orangeburg, SC (United States)

    1996-09-01

    To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned to hydraulics as a means of actuation. Hydraulics have always been the actuator of choice when designing heavy-life construction and mining equipment such as bulldozers, backhoes, and tunneling devices. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem) sophisticated modeling, analysis, and control experiments are usually needed. To support the development and deployment of new hydraulic manipulators Oak Ridge National Laboratory (ORNL) has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The hydraulics laboratory at ORNL has three different manipulators. First is a 6-Degree-of-Freedom (6-DoF), multi-planer, teleoperated, flexible controls test bed used for the development of waste tank clean-up manipulator controls, thermal studies, system characterization, and manipulator tracking. Finally, is a human amplifier test bed used for the development of an entire new class of teleoperated systems. To compliment the hardware in the hydraulics laboratory, ORNL has developed a hydraulics simulation capability including a custom package to model the hydraulic systems and manipulators for performance studies and control development. This paper outlines the history of hydraulic manipulator developments at ORNL, describes the hydraulics laboratory, discusses the use of the equipment within the laboratory, and presents some of the initial results from experiments and modeling associated with these hydraulic manipulators. Included are some of the results from the development of the human amplifier/de-amplifier concepts, the characterization of the thermal sensitivity of hydraulic systems, and end-point tracking accuracy studies. Experimental and analytical

  3. Hydraulic manipulator design, analysis, and control at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Kress, R.L.; Jansen, J.F.; Basher, A.M.H.

    1996-09-01

    To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned to hydraulics as a means of actuation. Hydraulics have always been the actuator of choice when designing heavy-life construction and mining equipment such as bulldozers, backhoes, and tunneling devices. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem) sophisticated modeling, analysis, and control experiments are usually needed. To support the development and deployment of new hydraulic manipulators Oak Ridge National Laboratory (ORNL) has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The hydraulics laboratory at ORNL has three different manipulators. First is a 6-Degree-of-Freedom (6-DoF), multi-planer, teleoperated, flexible controls test bed used for the development of waste tank clean-up manipulator controls, thermal studies, system characterization, and manipulator tracking. Finally, is a human amplifier test bed used for the development of an entire new class of teleoperated systems. To compliment the hardware in the hydraulics laboratory, ORNL has developed a hydraulics simulation capability including a custom package to model the hydraulic systems and manipulators for performance studies and control development. This paper outlines the history of hydraulic manipulator developments at ORNL, describes the hydraulics laboratory, discusses the use of the equipment within the laboratory, and presents some of the initial results from experiments and modeling associated with these hydraulic manipulators. Included are some of the results from the development of the human amplifier/de-amplifier concepts, the characterization of the thermal sensitivity of hydraulic systems, and end-point tracking accuracy studies. Experimental and analytical

  4. An electro-hydraulic servo control system research for CFETR blanket RH

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Changqi [Hefei University of Technology, Hefei 230009, Anhui (China); Tang, Hongjun, E-mail: taurustang@126.com [Hefei University of Technology, Hefei 230009, Anhui (China); Qi, Songsong [Hefei University of Technology, Hefei 230009, Anhui (China); Cheng, Yong; Feng, Hansheng; Peng, Xuebing; Song, Yuntao [Institute of Plasma Physics Chinese Academy of Sciences, Hefei 230031, Anhui (China)

    2014-11-15

    Highlights: • We discussed the conceptual design of CFETR blanket RH maintenance system. • The mathematical model of electro-hydraulic servo system was calculated. • A fuzzy adaptive PD controller was designed based on control theory and experience. • The co-simulation models of the system were established with AMESim/Simulink. • The fuzzy adaptive PD algorithm was designed as the core strategy of the system. - Abstract: Based on the technical design requirements of China Fusion Engineering Test Reactor (CFETR) blanket remote handling (RH) maintenance, this paper focus on the control method of achieving high synchronization accuracy of electro-hydraulic servo system. Based on fuzzy control theory and practical experience, a fuzzy adaptive proportional-derivative (PD) controller was designed. Then a more precise co-simulation model was established with AMESim/Simulink. Through the analysis of simulation results, a fuzzy adaptive PD control algorithm was designed as the core strategy of electro-hydraulic servo control system.

  5. An electro-hydraulic servo control system research for CFETR blanket RH

    International Nuclear Information System (INIS)

    Chen, Changqi; Tang, Hongjun; Qi, Songsong; Cheng, Yong; Feng, Hansheng; Peng, Xuebing; Song, Yuntao

    2014-01-01

    Highlights: • We discussed the conceptual design of CFETR blanket RH maintenance system. • The mathematical model of electro-hydraulic servo system was calculated. • A fuzzy adaptive PD controller was designed based on control theory and experience. • The co-simulation models of the system were established with AMESim/Simulink. • The fuzzy adaptive PD algorithm was designed as the core strategy of the system. - Abstract: Based on the technical design requirements of China Fusion Engineering Test Reactor (CFETR) blanket remote handling (RH) maintenance, this paper focus on the control method of achieving high synchronization accuracy of electro-hydraulic servo system. Based on fuzzy control theory and practical experience, a fuzzy adaptive proportional-derivative (PD) controller was designed. Then a more precise co-simulation model was established with AMESim/Simulink. Through the analysis of simulation results, a fuzzy adaptive PD control algorithm was designed as the core strategy of electro-hydraulic servo control system

  6. Dynamics three-tier hydraulic crane-manipulators

    OpenAIRE

    Lagerev I.A.; Lagerev A.V.

    2018-01-01

    The methods and generalized recommendations for modeling dynamic loading of load-bearing elements of steel structures of three-tier hydraulic cranes-manipulators are considered. Mathematical models have been developed to study the dynamics of moving elements of the crane-manipulator, the movement of the load-lifting machine on a stochastic uneven surface with a suspended load. The presented approaches can be used to calculate other types of jib cranes equipped with hydraulic drive.

  7. Integration of Flex Nozzle System and Electro Hydraulic Actuators to Solid Rocket Motors

    Science.gov (United States)

    Nayani, Kishore Nath; Bajaj, Dinesh Kumar

    2017-10-01

    A rocket motor assembly comprised of solid rocket motor and flex nozzle system. Integration of flex nozzle system and hydraulic actuators to the solid rocket motors are done after transportation to the required place where integration occurred. The flex nozzle system is integrated to the rocket motor in horizontal condition and the electro hydraulic actuators are assembled to the flex nozzle systems. The electro hydraulic actuators are connected to the hydraulic power pack to operate the actuators. The nozzle-motor critical interface are insulation diametrical compression, inhibition resin-28, insulation facial compression, shaft seal `O' ring compression and face seal `O' ring compression.

  8. Research on intelligent algorithm of electro - hydraulic servo control system

    Science.gov (United States)

    Wang, Yannian; Zhao, Yuhui; Liu, Chengtao

    2017-09-01

    In order to adapt the nonlinear characteristics of the electro-hydraulic servo control system and the influence of complex interference in the industrial field, using a fuzzy PID switching learning algorithm is proposed and a fuzzy PID switching learning controller is designed and applied in the electro-hydraulic servo controller. The designed controller not only combines the advantages of the fuzzy control and PID control, but also introduces the learning algorithm into the switching function, which makes the learning of the three parameters in the switching function can avoid the instability of the system during the switching between the fuzzy control and PID control algorithms. It also makes the switch between these two control algorithm more smoother than that of the conventional fuzzy PID.

  9. Global Energy-Optimal Redundancy Resolution of Hydraulic Manipulators: Experimental Results for a Forestry Manipulator

    Directory of Open Access Journals (Sweden)

    Jarmo Nurmi

    2017-05-01

    Full Text Available This paper addresses the energy-inefficiency problem of four-degrees-of-freedom (4-DOF hydraulic manipulators through redundancy resolution in robotic closed-loop controlled applications. Because conventional methods typically are local and have poor performance for resolving redundancy with respect to minimum hydraulic energy consumption, global energy-optimal redundancy resolution is proposed at the valve-controlled actuator and hydraulic power system interaction level. The energy consumption of the widely popular valve-controlled load-sensing (LS and constant-pressure (CP systems is effectively minimised through cost functions formulated in a discrete-time dynamic programming (DP approach with minimum state representation. A prescribed end-effector path and important actuator constraints at the position, velocity and acceleration levels are also satisfied in the solution. Extensive field experiments performed on a forestry hydraulic manipulator demonstrate the performance of the proposed solution. Approximately 15–30% greater hydraulic energy consumption was observed with the conventional methods in the LS and CP systems. These results encourage energy-optimal redundancy resolution in future robotic applications of hydraulic manipulators.

  10. WORKSPACE DRAWING FROM A MANIPULATOR ARM WITH 6 DOF

    Directory of Open Access Journals (Sweden)

    NAIDIN Gigi

    2011-06-01

    Full Text Available Modelling and simulation is an important aspect in robotic field. Knowing of the workspace is very important to the operation of manipulators arm. This paper investigates operational performance of space manipulator arm destined for industrial manufacturing, by defining and analyzing their workspace and manipulability measure. The authors show that manipulator arm developing requires the consideration of more efficient dynamic models and use of dedicated processing techniques such as Autodesk-Inventor 9, MATLAB, WorkSpace software.

  11. Design and Performance Evaluation of an Electro-Hydraulic Camless Engine Valve Actuator for Future Vehicle Applications.

    Science.gov (United States)

    Nam, Kanghyun; Cho, Kwanghyun; Park, Sang-Shin; Choi, Seibum B

    2017-12-18

    This paper details the new design and dynamic simulation of an electro-hydraulic camless engine valve actuator (EH-CEVA) and experimental verification with lift position sensors. In general, camless engine technologies have been known for improving fuel efficiency, enhancing power output, and reducing emissions of internal combustion engines. Electro-hydraulic valve actuators are used to eliminate the camshaft of an existing internal combustion engines and used to control the valve timing and valve duration independently. This paper presents novel electro-hydraulic actuator design, dynamic simulations, and analysis based on design specifications required to satisfy the operation performances. An EH-CEVA has initially been designed and modeled by means of a powerful hydraulic simulation software, AMESim, which is useful for the dynamic simulations and analysis of hydraulic systems. Fundamental functions and performances of the EH-CEVA have been validated through comparisons with experimental results obtained in a prototype test bench.

  12. Renal arteriovenous fistula: A rare complication of electro-hydraulic ...

    African Journals Online (AJOL)

    A 62-year-old man with type 1 Von Willebrand's disease was electively admitted to a Northern Ireland district general hospital for endoscopic management of a 1 cm right lower pole calculus. After pre-operative administration of appropriate haematological factors, flexible ureteroscopic electro-hydraulic lithotripsy (EHL).

  13. Industrial dual arm robot manipulator for precise assembly of mechanical parts

    Science.gov (United States)

    Park, Chanhun; Kim, Doohyung; Park, Kyoungtaik; Choi, Youngjin

    2007-12-01

    A new structure of dual arm robot manipulator which consists of two industrial 6-DOF arms and one 2-DOF Torso is introduced. Each industrial 6-DOF arm is able to be used as a stand-alone industrial 6-DOF robot manipulator and as a part of dual arm manipulator at the same time. These structures help the robot maker which is willing to succeed in the emerging dual arm robot market in order to have high competition for the current industrial robot market at same time. Self-collision detection algorithm for multi-arm robot and kinematics algorithms for the developed dual arm robot manipulator which are implemented in our controller are introduced.

  14. New method to improve dynamic stiffness of electro-hydraulic servo systems

    Science.gov (United States)

    Bai, Yanhong; Quan, Long

    2013-09-01

    Most current researches working on improving stiffness focus on the application of control theories. But controller in closed-loop hydraulic control system takes effect only after the controlled position is deviated, so the control action is lagged. Thus dynamic performance against force disturbance and dynamic load stiffness can’t be improved evidently by advanced control algorithms. In this paper, the elementary principle of maintaining piston position unchanged under sudden external force load change by charging additional oil is analyzed. On this basis, the conception of raising dynamic stiffness of electro hydraulic position servo system by flow feedforward compensation is put forward. And a scheme using double servo valves to realize flow feedforward compensation is presented, in which another fast response servo valve is added to the regular electro hydraulic servo system and specially utilized to compensate the compressed oil volume caused by load impact in time. The two valves are arranged in parallel to control the cylinder jointly. Furthermore, the model of flow compensation is derived, by which the product of the amplitude and width of the valve’s pulse command signal can be calculated. And determination rules of the amplitude and width of pulse signal are concluded by analysis and simulations. Using the proposed scheme, simulations and experiments at different positions with different force changes are conducted. The simulation and experimental results show that the system dynamic performance against load force impact is largely improved with decreased maximal dynamic position deviation and shortened settling time. That is, system dynamic load stiffness is evidently raised. This paper proposes a new method which can effectively improve the dynamic stiffness of electro-hydraulic servo systems.

  15. Development and design optimization of water hydraulic manipulator for ITER

    International Nuclear Information System (INIS)

    Kekaelaeinen, Teemu; Mattila, Jouni; Virvalo, Tapio

    2009-01-01

    This paper describes one of the research projects carried out in The Preparation of Remote Handling Engineers for ITER (PREFIT) program within the European Fusion Training Scheme (EFTS). This research project is focusing on the design and optimization of water hydraulic manipulators used to test several remote handling tasks of ITER at Divertor Test Platform 2 (DTP2), Tampere, Finland, and later in ITER. In this project, a water hydraulic manipulator designed and build by Department of Intelligent Hydraulics and Automation in Tampere University of Technology, Finland (TUT/IHA) is further optimized as a case study for a given manipulator requirement specification in order to illustrate and verify developed comprehensive design guidelines and performance metrics. Without meaningful manipulator performance parameters, the evaluation of alternative robot manipulators designs remains ad hoc at best. Therefore, more comprehensive design guidelines and performance metrics are needed for comparing and improving different existing manipulators versus task requirements or for comparing different digital prototypes at early design phase of manipulators. In this paper the description of the project, its background and developments are presented and discussed.

  16. Servoarm: a water hydraulic master-slave manipulator

    International Nuclear Information System (INIS)

    Wilson, K.B.

    1975-01-01

    A water-hydraulic-powered servomanipulator that minimizes inertia, weighs only 17 lb/arm, has a 22-lb capacity, provides a compact package, and is available at a relatively low cost has been developed. Because of the water hydraulic system and miniature sizes required, all components have been specially designed and developed. Programming is easily added, because a microcomputer and A/D conversion hardware are used for counterbalancing

  17. Manipulator arm for a nuclear reactor vessel inspection device

    International Nuclear Information System (INIS)

    1980-01-01

    A manipulator arm for a reactor vessel in-service inspection apparatus is adapted to transport a transducer array for ultrasonic examination of welds at any point in the vessel. The removal of the inspection device from the reactor vessel in an emergency presents a problem where a relatively long manipulator arm is used. This invention provides an improved arm with means for changing the normal orientation of the arm to a shorter one to permit safe removal of the inspection device from the reactor vessel. (author)

  18. Analysis of an controller design for an electro-hydraulic servo pressure regulator

    DEFF Research Database (Denmark)

    Pedersen, Henrik C.; Andersen, Torben Ole; Madsen, A. M.

    2009-01-01

    Mobile hydraulics is in a transition phase, where electronic sensors and digital signal processors are starting to become standard on a high number of machines, hereby replacing hydraulic pilot lines and oering new possibilities with regard to both control and feasibility. For controlling some...... of the existing hydraulic components there are, however, still a need for being able to generate a hydraulic pilot pressure, as e.g. almost all open-circuit pumps are hydraulically controlled. The focus of the current paper is therefore on the analysis and controller design an electro-hydraulic servo pressure...... regulator, which generates a hydraulic LS-pressure based on an electrical reference, hereby synergistically integrating knowledge from all parts of the mechatronics area. The servo pressure regulator is used to generate the LS-signal for a variable displacement pump, and the paper rst presents...

  19. System Topology Optimization - An Approach to System Design of Electro-Hydraulic-Mechanical Systems

    DEFF Research Database (Denmark)

    Andersen, T. O.; Hansen, M. R.; Conrad, Finn

    2003-01-01

    The current paper presents an approach to system design of combined electro-hydraulic-mechanical systems. The approach is based on the concurrent handling of the topology as well as the design parameters of the mechanical, hydraulic and controller sub- systems, respectively. Based on an initial...... design the procedure attempts to find the optimal topology and the related parameters. The topology considerations comprise the type of hydraulic pump, the employment of knee linkages or not as well as the type of hydraulic actuators. The design variables also include the signals to the proportional...... valve in a number of predefined load cases as well as the hydraulic and mechanical parameters....

  20. Concept development of a tendon arm manipulator and anthropomorphic robotic hand

    Science.gov (United States)

    Tolman, C. T.

    1987-01-01

    AMETEK/ORED inhouse research and development efforts leading toward a next-generation robotic manipulator arm and end-effector technology is summarized. Manipulator arm development has been directed toward a multiple-degree-of-freedom, flexible, tendon-driven concept referred to here as a Tendon Arm Manipulator (TAM). End-effector development has been directed toward a three-fingered, dextrous, tendon-driven, anthropomorphic configuration which is referred to as an Anthropomorphic Robotic Hand (ARH). Key technology issues are identified for both concepts.

  1. Concrete decontamination by electro-hydraulic scabbling

    Energy Technology Data Exchange (ETDEWEB)

    Goldfarb, V.; Gannon, R. [Textron Defense System, Everett, MA (United States)

    1995-10-01

    Textron Defense Systems (TDS) is developing an electro-hydraulic device that has the potential for faster, safer, and less expensive scabbling of contaminated concrete surfaces. In the device, shock waves and cavitating bubbles are produced in water by the electric pulses, and the direct and reflected shock waves impinging on the concrete surface result in the crushing and cracking of the concrete. Pulse energy, frequency, and traverse speed control the depth of the scabbling action. Performance thus far has demonstrated the capability of a prototype unit to process a swath 24 inches wide, up to 3/4 inch deep at a linear velocity of up to 6 feet per hour, i.e., at a scabbling rate of 12 sq. ft. per hour.

  2. Concrete decontamination by electro-hydraulic scabbling

    International Nuclear Information System (INIS)

    Goldfarb, V.; Gannon, R.

    1995-01-01

    Textron Defense Systems (TDS) is developing an electro-hydraulic device that has the potential for faster, safer, and less expensive scabbling of contaminated concrete surfaces. In the device, shock waves and cavitating bubbles are produced in water by the electric pulses, and the direct and reflected shock waves impinging on the concrete surface result in the crushing and cracking of the concrete. Pulse energy, frequency, and traverse speed control the depth of the scabbling action. Performance thus far has demonstrated the capability of a prototype unit to process a swath 24 inches wide, up to 3/4 inches deep at a linear velocity of up to 6 feet per hour, i.e., at a scabbling rate of 12 sq. ft. per hour

  3. Penggantian Slave Arm Ms-manipulator Hotcell Uji 02 Dan 03 Irm

    OpenAIRE

    Gogo, Antonio; Basiran

    2015-01-01

    ─ The replacement of the failure slave arm unit of MS-manipulator in hot cell 02 and 03 of Radiometallurgy Installations (IRM) has been done. This replacement purposes in order to refunctioned the failure MS-manipulator (5 units) in examination hot cell 02 and 03. The slave arm unit of MS-manipulator in examination hot cell 02 and 03 using a hanging device so it is impossible to pulled the slave arm units out to the operating area. The handling process cover; setting zero position on master a...

  4. Output Feedback Control of Electro-Hydraulic Cylinder Drives using the Twisting Algorithm

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2014-01-01

    contributions in literature. This paper considers the twisting algorithm when applied directly for output feedback control, and with the design based on a reduced order model representation of an arbitrary valve driven hydraulic cylinder drive. The consequence of implementing such a controller with the well......This paper discusses the utilization of the so-called twisting algorithm when applied in output feedback position control schemes for electro-hydraulic cylinder drives. The twisting controller was the first second order sliding controller ever introduced, and can structure-wise be considered...... feedback controller may be successfully applied to hydraulic valve driven cylinder drives, with performance being on the level with a conventional surface based first order sliding mode controller....

  5. Nonlinear, Adaptive and Fault-tolerant Control for Electro-hydraulic Servo Systems

    DEFF Research Database (Denmark)

    Choux, Martin

    is designed and implemented on the test bed that successfully diagnoses internal or external leakages, friction variations in the actuator or fault related to pressure sensors. The presented algorithm uses the position and pressure measurements to detect and isolate faults, avoiding missed detection and false...... numerous attractive properties, hydraulic systems are always subject to potential leakages in their components, friction variation in their hydraulic actuators and deciency in their sensors. These violations of normal behaviour reduce the system performances and can lead to system failure...... if they are not detected early and handled. Moreover, the task of controlling electro hydraulic systems for high performance operations is challenging due to the highly nonlinear behaviour of such systems and the large amount of uncertainties present in their models. This thesis focuses on nonlinear adaptive fault...

  6. Emergency disconnect means for the manipulator arm of a nuclear reactor vessel inspection apparatus

    International Nuclear Information System (INIS)

    Jacobs, F.; Morris, D.W.

    1980-01-01

    An emergency disconnect means is disclosed for uncoupling a portion of the linkage means which connects the several segments of an articulating manipulator arm employed in a nuclear reactor vessel inspection device. One of the motor housings included in the manipulator arm's segmented drive train is pivotably coupled between two segments thereof. In the event of power failure or the necessity of manual retraction of the manipulator arm from within the vessel, a lever is manually operated and moved from its normally locked position wherein the motor housing is positionally fixed to a release position wherein the motor housing and the remainder of the manipulator arm segments connected forwardly thereof are pivotally released to shorten the normal arm reach and alter the normal orientation of the manipulator arm to expedite removal without danger of collision. (auth)

  7. Nonlinear dynamic modeling for smart material electro-hydraulic actuator development

    Science.gov (United States)

    Larson, John P.; Dapino, Marcelo J.

    2013-03-01

    Smart material electro-hydraulic actuators use hydraulic rectification by one-way check valves to amplify the motion of smart materials, such as magnetostrictives and piezoelectrics, in order to create compact, lightweight actuators. A piston pump driven by a smart material is combined with a hydraulic cylinder to form a self-contained, power-by-wire actuator that can be used in place of a conventional hydraulic system without the need for hydraulic lines and a centralized pump. The performance of an experimental actuator driven by a 12.7 mm diameter, 114 mm length Terfenol-D rod is evaluated over a range of applied input frequencies, loads, and currents. The peak performance achieved is 37 W, moving a 220 N load at a rate of 17 cm/s and producing a blocked pressure of 12.5 MPa. Additional tests are conducted to quantify the dynamic behavior of the one-way reed valves using a scanning laser vibrometer to identify the frequency response of the reeds and the effect of the valve seat and fluid mass loading. A lumped-parameter model is developed for the system that includes valve inertia and fluid response nonlinearities, and the model results are compared with the experimental data.

  8. Tracking control of the hydraulically actuated flexible manipulator

    International Nuclear Information System (INIS)

    Kwon, D.S.; Babcock, S.M.; Burks, B.L.; Kress, R.L.

    1995-01-01

    The remediation of single-shell radioactive waste storage tanks is one of the urgent tasks of the Department of Energy that challenge state-of-the-art equipment and methods. The use of long-reach manipulators is being seriously considered for this remediation task. Because high payload capacity and high length-to-cross-section ratio requirements, these long-reach manipulator systems are expected to use hydraulic actuators and to exhibit significant structural flexibility. The controller has been designed to compensate for the hydraulic actuator dynamics by using a load-compensated velocity feedforward loop and to increase the bandwidth by using a pressure feed backloop. Shaping filter techniques have been applied as a feedforward controller to avoid structural vibrations during operation. Among various types of shaping filter methods investigated an approach, referred to as a ''feedforward simulation filter'' that uses embedded simulation, has been presented

  9. Analysis of the jet pipe electro-hydraulic servo valve with finite element methods

    Directory of Open Access Journals (Sweden)

    Kaiyu Zhao

    2018-01-01

    Full Text Available The dynamic characteristics analysis about the jet pipe electro-hydraulic servo valve based on experience and mathematical derivation was difficult and not so precise. So we have analysed the armature feedback components, torque motor and jet pipe receiver in electrohydraulic servo valve by sophisticated finite element analysis tools respectively and have got physical meaning data on these parts. Then the data were fitted by Matlab and the mathematical relationships among them were calculated. We have done the dynamic multi-physical fields’ Simulink co-simulation using above mathematical relationship, and have got the input-output relationship of the overall valve, the frequency response and step response. This work can show the actual working condition accurately. At the same time, we have considered the materials and the impact of the critical design dimensions in the finite element analysis process. It provides some new ideas to the overall design of jet pipe electro-hydraulic servo valve.

  10. Admittance Control of a Multi-Finger Arm Based on Manipulability of Fingers

    Directory of Open Access Journals (Sweden)

    Jian Huang

    2011-09-01

    Full Text Available In the previous studies, admittance control and impedance control for a finger-arm robot using the manipulability of the finger were studied and methods of realizing the controls have been proposed. In this study, two 3-DOF fingers are attached to the end-effector of a 6-DOF arm to configure a multi-finger arm robot. Based on the previous methods, the authors have proposed an admittance control for a multi-finger arm robot using the manipulability of the fingers in this study. Algorithms of the averaging method and the mini-max method were introduced to establish a manipulability criterion of the two fingers in order to generate a cooperative movement of the arm. Comparison of the admittance controls combined with the top search method and local optimization method for the multi-finger arm robot was made and features of the control methods were also discussed. The stiffness control and damping control were experimentally evaluated to demonstrate the effectiveness of the proposed methods.

  11. Development of Heavy-Duty and High-Precision Hydraulic Manipulator for Inspection, Maintenance and Decommission of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sung Uk; Seo, Yong-chil; Jung, Kyung Min; Kim, Chang-hoi; Choi, Byung-seon; Moon, Jei-kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    Robotic manipulators have been used for inspection, maintenance and decommission of nuclear power plants because nuclear power plants have high radiation and human workers cannot easily access the plants. And also, to inspecting, maintaining and decommissioning nuclear power plants require various manipulators. Only one manipulator cannot response to many required tasks. The existing manipulators that was used at nuclear power plants can only operate only focused specific task and cannot be used at several tasks. The actuators used at manipulators are varied and many companies sell actuators depending on power, torque and speed. However, the commercial product is not standardized. Therefore, the development of manipulator is time consuming and expensive. The essential item of a manipulator is an actuator module. If actuator module is standardized, it’s easier to develop a manipulator and also maintain a manipulator. Recently, manipulator having high-radiation, high-duty and high-precision is necessary to inspection, maintain and decommissioning of nuclear power plants. Hydraulic actuator has been used to development high-duty manipulator. But control performance of a hydraulic actuator is not better than that of an electric actuator so that hydraulic manipulator cannot easily satisfy the required precision. In this paper, we developed high-duty and high-precision actuator modules and hydraulic manipulator using the developed actuator modules. The developed hydraulic manipulator have a payload of 250kg and a precision of ±1mm. Four modularized hydraulic actuator modules were developed for inspection, maintenance and decommission. Using the developed actuator modules, the manipulator for decommissioning is easily developed. And also, various manipulators having different kinematic structure for specific tasks will be easily developed by using hydraulic modules.

  12. Development of Heavy-Duty and High-Precision Hydraulic Manipulator for Inspection, Maintenance and Decommission of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Lee, Sung Uk; Seo, Yong-chil; Jung, Kyung Min; Kim, Chang-hoi; Choi, Byung-seon; Moon, Jei-kwon

    2016-01-01

    Robotic manipulators have been used for inspection, maintenance and decommission of nuclear power plants because nuclear power plants have high radiation and human workers cannot easily access the plants. And also, to inspecting, maintaining and decommissioning nuclear power plants require various manipulators. Only one manipulator cannot response to many required tasks. The existing manipulators that was used at nuclear power plants can only operate only focused specific task and cannot be used at several tasks. The actuators used at manipulators are varied and many companies sell actuators depending on power, torque and speed. However, the commercial product is not standardized. Therefore, the development of manipulator is time consuming and expensive. The essential item of a manipulator is an actuator module. If actuator module is standardized, it’s easier to develop a manipulator and also maintain a manipulator. Recently, manipulator having high-radiation, high-duty and high-precision is necessary to inspection, maintain and decommissioning of nuclear power plants. Hydraulic actuator has been used to development high-duty manipulator. But control performance of a hydraulic actuator is not better than that of an electric actuator so that hydraulic manipulator cannot easily satisfy the required precision. In this paper, we developed high-duty and high-precision actuator modules and hydraulic manipulator using the developed actuator modules. The developed hydraulic manipulator have a payload of 250kg and a precision of ±1mm. Four modularized hydraulic actuator modules were developed for inspection, maintenance and decommission. Using the developed actuator modules, the manipulator for decommissioning is easily developed. And also, various manipulators having different kinematic structure for specific tasks will be easily developed by using hydraulic modules

  13. Water hydraulic manipulator for fail safe and fault tolerant remote handling operations at ITER

    International Nuclear Information System (INIS)

    Nieminen, Peetu; Esque, Salvador; Muhammad, Ali; Mattila, Jouni; Vaeyrynen, Jukka; Siuko, Mikko; Vilenius, Matti

    2009-01-01

    Department of Intelligent Hydraulics and Automation (IHA) of Tampere University of Technology has been involved in the European Fusion program since 1994 within the ITER reactor maintenance activities. In this paper we discuss the design and development of a six degrees of freedom water hydraulic manipulator with a force feedback for teleoperation tasks. The manipulator is planned to be delivered to Divertor Test Platform 2 (DTP2) during year 2008. The paper also discusses the possibility to improve the fail safe and redundant operation of the manipulator. During the design of the water hydraulic manipulator, special provisions have been made in order to meet the safety requirements such as servo valve block for redundant operation and safety vane brakes for fail safe operation.

  14. Emergency retraction mechanism for the manipulator arm of a nuclear reactor vessel inspection apparatus

    International Nuclear Information System (INIS)

    1980-01-01

    Nuclear reactor vessels are made using numerous welds. These have to be inspected, often using ultrasonic transducers mounted on a manipulator arm. This invention seeks to solve the problem of retracting the manipulator arm should an emergency occur while it is fully extended, particularly within one of the reactor vessel nozzles. Of specific concern is the situation where power fails with the manipulator arm so extended. Details are given of an emergency retraction mechanism for use in reactor vessel inspection apparatus. A manual retraction means is used; the manipulator arm is slidably mounted within a frame. This comprises a member mounted on the arm for looping engagement by a cable, the cable being fixed at one end of the arm frame and engaging the member, and a clamp for detachably securing the cable at its other end to the arm frame at a point which is accessible from above the vessel. (U.K.)

  15. Desain Proportional Integral Derrivative (Pid) Controller Pada Model Arm Robot Manipulator

    OpenAIRE

    Pratama, Adhityanendra Pandu; Munadi, Munadi

    2014-01-01

    Dalam rangka menuju proses industrialisasi modern di negara Indonesia, harus didukung dengan teknologi yang canggih, contoh nya adalah arm robot manipulator. sebagai pelaku proses produksi sehingga dihasilkan ketepatan,kepresisian, dan kefektifan pada proses produksi. Dengan hal tersebut dibuat sebuah desain kontrol PID pada arm robot manipulator dengan tujuan menghasilkan tingkat presisi dan kestabilan yang lebih baik. Kontroler tersebut didesain, disimulasikan, dan diaplikasikan pada ha...

  16. Admittance Control of a Multi-Finger Arm Based on Manipulability of Fingers

    Directory of Open Access Journals (Sweden)

    Takayuki Hori

    2011-09-01

    Full Text Available In the previous studies, admittance control and impedance control for a finger‐arm robot using the manipulability of the finger were studied and methods of realizing the controls have been proposed. In this study, two 3‐DOF fingers are attached to the end‐effector of a 6‐DOF arm to configure a multi‐finger arm robot. Based on the previous methods, the authors have proposed an admittance control for a multi‐finger arm robot using the manipulability of the fingers in this study. Algorithms of the averaging method and the mini‐max method were introduced to establish a manipulability criterion of the two fingers in order to generate a cooperative movement of the arm. Comparison of the admittance controls combined with the top search method and local optimization method for the multi‐finger arm robot was made and features of the control methods were also discussed. The stiffness control and damping control were experimentally evaluated to demonstrate the effectiveness of the proposed methods.

  17. Linear Perturbation Adaptive Control of Hydraulically Driven Manipulators

    DEFF Research Database (Denmark)

    Andersen, T.O.; Hansen, M.R.; Conrad, Finn

    2004-01-01

    control.Using the Lyapunov approach, under slowly time-varying assumptions, it is shown that the tracking error and the parameter error remain bounded. This bound is a function of the ideal parameters and a bounded disturbance. The control algorithm decouples and linearizes the manipulator so that each......A method for synthesis of a robust adaptive scheme for a hydraulically driven manipulator, that takes full advantage of any known system dynamics to simplify the adaptive control problem for the unknown portion of the dynamics is presented. The control method is based on adaptive perturbation...

  18. Whole arm manipulation planning based on feedback velocity fields and sampling-based techniques.

    Science.gov (United States)

    Talaei, B; Abdollahi, F; Talebi, H A; Omidi Karkani, E

    2013-09-01

    Changing the configuration of a cooperative whole arm manipulator is not easy while enclosing an object. This difficulty is mainly because of risk of jamming caused by kinematic constraints. To reduce this risk, this paper proposes a feedback manipulation planning algorithm that takes grasp kinematics into account. The idea is based on a vector field that imposes perturbation in object motion inducing directions when the movement is considerably along manipulator redundant directions. Obstacle avoidance problem is then considered by combining the algorithm with sampling-based techniques. As experimental results confirm, the proposed algorithm is effective in avoiding jamming as well as obstacles for a 6-DOF dual arm whole arm manipulator. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Optimal arm posture control and tendon traction forces of a coupled tendon-driven manipulator

    International Nuclear Information System (INIS)

    Ma, Shugen

    1997-01-01

    In this study, the optimum arm posture of a coupled tendon-driven multijoint manipulator arm (or CT Arm) at maximum payload output was derived and the corresponding tendon traction forces were also analyzed, during management of a heavy payload by the manipulator in a gravity environment. The CT Arm is special tendon traction transmission mechanism in which a pair of tendons used to drive a joint is pulled from base actuators via pulleys mounted on the base-side joints. This mechanism enables optimal utilization of the coupled drive function of tendon traction forces and thus enables the lightweight manipulator to exhibit large payload capability. The properties of the CT Arm mechanism are elucidated by the proposed optimal posture control scheme. Computer simulation was also executed to verify the validity of the proposed control scheme. (author)

  20. Dual-arm manipulation module for use in decontamination and decommissioning operations

    International Nuclear Information System (INIS)

    Hamel, W.R.; Haley, D.C.; Dixon, W.E.

    1994-01-01

    A dual-arm manipulation module is under development for application in decontamination and decommissioning (D ampersand D) tasks. The development is led by Oak Ridge National Laboratory with support from Sandia National Laboratories, and with university and industry participation. The project is part of the Robotics Technology Development Program funded by the US Department of Energy, Environmental Restoration and Waste Management, Office of Technology Development. The dual-arm module is designed to provide dexterous manipulation capability for remote characterization, decontamination, and dismantlement operations, and the module is reconfigurable to meet various deployment requirements. Remote manipulation capability can benefit D ampersand D activities through reduced worker exposure to both contaminant and industrial hazards. When tasks conditions permit, increased use of robotic features reduce costs by increased efficiency of operation

  1. Simulation of robot manipulators

    International Nuclear Information System (INIS)

    Kress, R.L.; Babcock, S.M.; Bills, K.C.; Kwon, D.S.; Schoenwald, D.A.

    1995-01-01

    This paper describes Oak Ridge National Laboratory's development of an environment for the simulation of robotic manipulators. Simulation includes the modeling of kinematics, dynamics, sensors, actuators, control systems, operators, and environments. Models will be used for manipulator design, proposal evaluation, control system design and analysis, graphical preview of proposed motions, safety system development, and training. Of particular interest is the development of models for robotic manipulators having at least one flexible link. As a first application, models have been developed for the Pacific Northwest Laboratories' Flexible Beam Testbed which is a one-Degree-Of-Freedom, flexible arm with a hydraulic base actuator. Initial results show good agreement between model and experiment

  2. Electro-Pneumatic Control System with Hydraulically Positioning Actuator Motor

    Directory of Open Access Journals (Sweden)

    V. N. Pilgunov

    2016-01-01

    Full Text Available A compressibility of the actuating fluid of a pneumatic drive (compressed air leads to significant landing of the pneumatic cylinder piston at the time of stop and hold of the load, a constant component of which can fluctuate significantly for the holding period.There are a lot of factors, which have a significant impact on the landing value of piston. Those are: an initial position of the piston at its stop, which determines the volume of the an active area of the piston, a value of the constant load component at the time of stop and its variation for the holding period, a transfer coefficient of the position component of the load, an active area of the pneumatic cylinder piston, as well as reduction in atmospheric pressure, which can significantly affect the operation of the control systems of small aircrafts flying at high altitudes.To reduce the landing value of piston due to changing value of the constant load component for its holding period, it is proposed to use a hydraulic positioner, which comprises a hydraulic cylinder the rod of which is rigidly connected to the rod of the pneumatic cylinder through the traverse, a cross-feed valve of the hydro-cylinder cavities with discrete electro-magnetic control, and adjustable chokes.A programmable logic controller provides the hydraulic positioner control. At the moment the piston stops and the load is held the cross-feed valve overlaps the hydro-cylinder cavities thereby locking the pneumatic cylinder piston and preventing its landing. With available pneumatic cylinder-controlled signal the cross-feed valve connects the piston and rod cavities of the positioner hydro-cylinder, the pneumatic cylinder piston is released and becomes capable of moving.A numerical estimate of landing of the pneumatic cylinder piston and its positioning quality is of essential interest. For this purpose, a technique to calculate the landing of piston has been developed taking into consideration that different

  3. An innovative approach for modeling and simulation of an automated industrial robotic arm operated electro-pneumatically

    Science.gov (United States)

    Popa, L.; Popa, V.

    2017-08-01

    The article is focused on modeling an automated industrial robotic arm operated electro-pneumatically and to simulate the robotic arm operation. It is used the graphic language FBD (Function Block Diagram) to program the robotic arm on Zelio Logic automation. The innovative modeling and simulation procedures are considered specific problems regarding the development of a new type of technical products in the field of robotics. Thus, were identified new applications of a Programmable Logic Controller (PLC) as a specialized computer performing control functions with a variety of high levels of complexit.

  4. Augmented reality user interface for mobile ground robots with manipulator arms

    Science.gov (United States)

    Vozar, Steven; Tilbury, Dawn M.

    2011-01-01

    Augmented Reality (AR) is a technology in which real-world visual data is combined with an overlay of computer graphics, enhancing the original feed. AR is an attractive tool for teleoperated UGV UIs as it can improve communication between robots and users via an intuitive spatial and visual dialogue, thereby increasing operator situational awareness. The successful operation of UGVs often relies upon both chassis navigation and manipulator arm control, and since existing literature usually focuses on one task or the other, there is a gap in mobile robot UIs that take advantage of AR for both applications. This work describes the development and analysis of an AR UI system for a UGV with an attached manipulator arm. The system supplements a video feed shown to an operator with information about geometric relationships within the robot task space to improve the operator's situational awareness. Previous studies on AR systems and preliminary analyses indicate that such an implementation of AR for a mobile robot with a manipulator arm is anticipated to improve operator performance. A full user-study can determine if this hypothesis is supported by performing an analysis of variance on common test metrics associated with UGV teleoperation.

  5. Extended state observer–based fractional order proportional–integral–derivative controller for a novel electro-hydraulic servo system with iso-actuation balancing and positioning

    Directory of Open Access Journals (Sweden)

    Qiang Gao

    2015-12-01

    Full Text Available Aiming at balancing and positioning of a new electro-hydraulic servo system with iso-actuation configuration, an extended state observer–based fractional order proportional–integral–derivative controller is proposed in this study. To meet the lightweight requirements of heavy barrel weapons with large diameters, an electro-hydraulic servo system with a three-chamber hydraulic cylinder is especially designed. In the electro-hydraulic servo system, the balance chamber of the hydraulic cylinder is used to realize active balancing of the unbalanced forces, while the driving chambers consisting of the upper and lower chambers are adopted for barrel positioning and dynamic compensation of external disturbances. Compared with conventional proportional–integral–derivative controllers, the fractional order proportional–integral–derivative possesses another two adjustable parameters by expanding integer order to arbitrary order calculus, resulting in more flexibility and stronger robustness of the control system. To better compensate for strong external disturbances and system nonlinearities, the extended state observer strategy is further introduced to the fractional order proportional–integral–derivative control system. Numerical simulation and bench test indicate that the extended state observer–based fractional order proportional–integral–derivative significantly outperforms proportional–integral–derivative and fractional order proportional–integral–derivative control systems with better control accuracy and higher system robustness, well demonstrating the feasibility and effectiveness of the proposed extended state observer–based fractional order proportional–integral–derivative control strategy.

  6. Modelling and Simulation of Mobile Hydraulic Crane with Telescopic Arm

    DEFF Research Database (Denmark)

    Nielsen, Brian; Pedersen, Henrik Clemmensen; Andersen, Torben Ole

    2005-01-01

    For loader crane applications resolved motion control is assumed to be one of the areas for development in the future. To develop and evaluate different control strategies for a resolved motion control system, information about the dynamic behaviour of these cranes is necessary. In the current...... paper a model of a loader crane with a flexible telescopic arm is presented, which may be used for evaluating control strategies. The telescopic arm is operated by four actuators connected hydraulically by a parallel circuit. The operating sequences of the individual actuators is therefore...

  7. Comparison of dynamic analysis of a Schilling hydraulic manipulator with experimental results

    International Nuclear Information System (INIS)

    Baker, C.P.; Lew, J.Y.; Evans, M.S.; Magee, D.P.

    1993-07-01

    Two independent models of the dynamics of a Schilling Titan II hydraulic manipulator were developed and compared in order to obtain an accurate model of the manipulator dynamics. These models will be used in the development of feedback control laws and active damping algorithms. One of the model is an analytical model which was developed open-quotes by handclose quotes with the assistance of computer symbolic manipulation. The other is a numerical model developed using a commercially available dynamics code. The data from these models were then compared with experimental data from an actual Titan II manipulator

  8. A compound control strategy combining velocity compensation with ADRC of electro-hydraulic position servo control system.

    Science.gov (United States)

    Gao, Bingwei; Shao, Junpeng; Yang, Xiaodong

    2014-11-01

    In order to enhance the anti-jamming ability of electro-hydraulic position servo control system at the same time improve the control precision of the system, a compound control strategy that combines velocity compensation with Active Disturbance Rejection Controller (ADRC) is proposed, and the working principle of the compound control strategy is given. ADRC controller is designed, and the extended state observer is used for observing internal parameters uncertainties and external disturbances, so that the disturbances of the system are suppressed effectively. Velocity compensation controller is designed and the compensation model is derived to further improve the positioning accuracy of the system and to achieve the velocity compensation without disturbance. The compound control strategy is verified by the simulation and experiment respectively, and the simulation and experimental results show that the electro-hydraulic position servo control system with ADRC controller can effectively inhibit the external disturbances, the precise positioning control is realized after introducing the velocity compensation controller, and verify that the compound control strategy is effective. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  9. Decommissioning of hot cells using a hydraulically powered servo manipulator

    International Nuclear Information System (INIS)

    Asquith, J.D.; Loughborough, D.

    1993-01-01

    This paper describes the preparations and initial trials involved in remotely dismantling the containment boxes within two concrete shielded hot cells at Harwell Laboratory using a hydraulically powered servo manipulator, ARTISAN. The manipulator deploys a variety of tools for cutting operations. The modular design has enabled it to be specifically configured for this application by adjusting the link lengths using spacers between the joints. In addition to the remote handling requirements, a new posting and ventilation system for the facility is outlined. Trials with ARTISAN in an in-active mock-up have now been successfully completed, and the manipulator is installed in the active facility. The considerations and approach adopted in this project are typical of many situations where remote techniques are required for decommissioning activities. (author)

  10. Using Feedback Error Learning for Control of Electro Hydraulic Servo System by Laguerre

    Directory of Open Access Journals (Sweden)

    Amir Reza Zare Bidaki

    2014-01-01

    Full Text Available In this paper, a new Laguerre controller is proposed to control the electro hydraulic servo system. The proposed controller uses feedback error learning method and leads to significantly improve performance in terms of settling time and amplitude of control signal rather than other controllers. All derived results are validated by simulation of nonlinear mathematical model of the system. The simulation results show the advantages of the proposed method for improved control in terms of both settling time and amplitude of control signal.

  11. Continuum robot arms inspired by cephalopods

    Science.gov (United States)

    Walker, Ian D.; Dawson, Darren M.; Flash, Tamar; Grasso, Frank W.; Hanlon, Roger T.; Hochner, Binyamin; Kier, William M.; Pagano, Christopher C.; Rahn, Christopher D.; Zhang, Qiming M.

    2005-05-01

    In this paper, we describe our recent results in the development of a new class of soft, continuous backbone ("continuum") robot manipulators. Our work is strongly motivated by the dexterous appendages found in cephalopods, particularly the arms and suckers of octopus, and the arms and tentacles of squid. Our ongoing investigation of these animals reveals interesting and unexpected functional aspects of their structure and behavior. The arrangement and dynamic operation of muscles and connective tissue observed in the arms of a variety of octopus species motivate the underlying design approach for our soft manipulators. These artificial manipulators feature biomimetic actuators, including artificial muscles based on both electro-active polymers (EAP) and pneumatic (McKibben) muscles. They feature a "clean" continuous backbone design, redundant degrees of freedom, and exhibit significant compliance that provides novel operational capacities during environmental interaction and object manipulation. The unusual compliance and redundant degrees of freedom provide strong potential for application to delicate tasks in cluttered and/or unstructured environments. Our aim is to endow these compliant robotic mechanisms with the diverse and dexterous grasping behavior observed in octopuses. To this end, we are conducting fundamental research into the manipulation tactics, sensory biology, and neural control of octopuses. This work in turn leads to novel approaches to motion planning and operator interfaces for the robots. The paper describes the above efforts, along with the results of our development of a series of continuum tentacle-like robots, demonstrating the unique abilities of biologically-inspired design.

  12. Degradation modeling and experiment of electro-hydraulic shift valve in contamination circumstances

    Directory of Open Access Journals (Sweden)

    Yong Liu

    2015-05-01

    Full Text Available In this article, a degradation assessment model has been proposed for electro-hydraulic shift valve in power-shift steering transmission. Our work is motivated by the failure mechanism of abrasive wear with a mathematic model. Abrasive wear will consecutively enlarge the clearance between the friction pairs. It is an overwhelming wear mechanism in the degradation of shift valve within serious contaminated fluid. Herein, a mathematic model is proposed by considering particle morphology and abrasion theory. Such model has been verified for its applicability and accuracy through comparison between the theoretical and experimental results.

  13. Development of hydraulic conductivity evaluation of rocks using EK (Electro Kinetic) phenomenon (Part 2). Experimental study on hydraulic conductivity evaluation by propagation velocity of EK potential

    International Nuclear Information System (INIS)

    Kubota, Kenji; Suzuki, Koichi

    2012-01-01

    Hydraulic conductivity is one of the most important engineering properties to investigate geological structure for high level radioactive waste (HLW) disposal and/or carbon dioxide (CO 2 ) geological storage. We are developing an estimation method of hydraulic conductivity by geophysical methods cost-effectively. When an elastic wave is propagated into rocks, a weak potential is generated. This is called EK (Electro Kinetic) potential, which may have a correlation with hydraulic conductivity. Hydraulic conductivity can be estimated by measuring the propagation velocity of the EK potential. We conducted laboratory measurements of propagation velocity of EK potential by using soil and rock samples. The results demonstrated that the velocity of EK potential increased as frequency increased, and the velocity increased as hydraulic conductivity of each sample increased at the same frequency condition. These tendencies corresponded to a theory of EK potential. We calculated hydraulic conductivity by comparing measured and theoretical velocity of the EK potential based on its frequency characteristics. The differences between calculated and sample hydraulic conductivity were under one order when hydraulic conductivity of the sample was from 10 -6 m/s to 10 -4 m/s. This suggests that hydraulic conductivity from 10 -6 m/s to 10 -4 m/s can be estimated by velocity of the EK potential. (author)

  14. Concrete decontamination by Electro-Hydraulic Scabbling (EHS). Topical report

    International Nuclear Information System (INIS)

    1996-01-01

    Electro-Hydraulic Scabbling (EHS) technology and equipment for decontaminating concrete structures from radionuclides, organic substances, and hazardous metals is being developed by Textron Systems Division (TSD). This wet scabbling technique involves the generation of powerful shock waves and intense cavitation by a strong pulsed electric discharge in a water layer at the concrete surface. The high pressure impulse results in stresses which crack and peel off a concrete layer of a controllable thickness. Scabbling produces contaminated debris of relatively small volume which can be easily removed, leaving clean bulk concrete. This new technology is being developed under Contract No. DE-AC21-93MC30164. The project objective is to develop and demonstrate a cost-efficient, rapid, controllable process to remove the surface layer of contaminated concrete while generating minimal secondary waste. The primary target of this program is uranium-contaminated concrete floors which constitute a substantial part of the contaminated area at DOE weapon facilities

  15. Control of flexible robots with prismatic joints and hydraulic drives

    International Nuclear Information System (INIS)

    Love, L.J.; Kress, R.L.; Jansen, J.F.

    1997-01-01

    The design and control of long-reach, flexible manipulators has been an active research topic for over 20 years. Most of the research to date has focused on single link, fixed length, single plane of vibration test beds. In addition, actuation has been predominantly based upon electromagnetic motors. Ironically, these elements are rarely found in the existing industrial long-reach systems. One example is the Modified Light Duty Utility Arm (MLDUA) designed and built by Spar Aerospace for Oak Ridge National Laboratory (ORNL). This arm operates in larger, underground waste storage tanks located at ORNL. The size and nature of the tanks require that the robot have a reach of approximately 15 ft and a payload capacity of 250 lb. In order to achieve these criteria, each joint is hydraulically actuated. Furthermore, the robot has a prismatic degree-of-freedom to ease deployment. When fully extended, the robot's first natural frequency is 1.76 Hz. Many of the projected tasks, coupled with the robot's flexibility, present an interesting problem. How will many of the existing flexure control algorithms perform on a hydraulic, long-reach manipulator with prismatic links? To minimize cost and risk of testing these algorithms on the MLDUA, the authors have designed a new test bed that contains many of the same elements. This manuscript described a new hydraulically actuated, long-reach manipulator with a flexible prismatic link at ORNL. Focus is directed toward both modeling and control of hydraulic actuators as well as flexible links that have variable natural frequencies

  16. Real-time tracking control of electro-hydraulic force servo systems using offline feedback control and adaptive control.

    Science.gov (United States)

    Shen, Gang; Zhu, Zhencai; Zhao, Jinsong; Zhu, Weidong; Tang, Yu; Li, Xiang

    2017-03-01

    This paper focuses on an application of an electro-hydraulic force tracking controller combined with an offline designed feedback controller (ODFC) and an online adaptive compensator in order to improve force tracking performance of an electro-hydraulic force servo system (EHFS). A proportional-integral controller has been employed and a parameter-based force closed-loop transfer function of the EHFS is identified by a continuous system identification algorithm. By taking the identified system model as a nominal plant model, an H ∞ offline design method is employed to establish an optimized feedback controller with consideration of the performance, control efforts, and robustness of the EHFS. In order to overcome the disadvantage of the offline designed controller and cope with the varying dynamics of the EHFS, an online adaptive compensator with a normalized least-mean-square algorithm is cascaded to the force closed-loop system of the EHFS compensated by the ODFC. Some comparative experiments are carried out on a real-time EHFS using an xPC rapid prototype technology, and the proposed controller yields a better force tracking performance improvement. Copyright © 2016. Published by Elsevier Ltd.

  17. Hydraulic Arm Modeling via Matlab SimHydraulics

    Czech Academy of Sciences Publication Activity Database

    Věchet, Stanislav; Krejsa, Jiří

    2009-01-01

    Roč. 16, č. 4 (2009), s. 287-296 ISSN 1802-1484 Institutional research plan: CEZ:AV0Z20760514 Keywords : simulatin modeling * hydraulics * SimHydraulics Subject RIV: JD - Computer Applications, Robotics

  18. Traction-drive seven degrees-of-freedom telerobot arm: A concept for manipulation in space

    International Nuclear Information System (INIS)

    Kuban, D.P.; Williams, D.M.

    1987-01-01

    As man seeks to expand his dominion into new environments, the demand increases for machines that perform useful functions in remote locations. This new concept for manipulation in space is based on knowledge and experience gained from manipulator systems developed to meet the needs of remote nuclear applications. It merges the best characteristics of teleoperation and robotic technologies. This paper summarizes the report of a study performed for NASA Langley Research Center. The design goals for the telerobot, a mechanical description, and technology areas that must be addressed for successful implementation will be presented and discussed. The concept incorporates mechanical traction drives, redundant kinematics, and modular arm subelements to provide a backlash-free manipulator capable of obstacle avoidance. Further development of this arm is in progress at the Oak Ridge National Laboratory

  19. Simulation of the electro-hydraulic control system of a BWR-5

    International Nuclear Information System (INIS)

    Acosta, M.; Montoya, J.; Chavez, H.

    1986-01-01

    The methodology used to develop the mathematical models for the simulation of the principal turbine electro-hydraulic control of the Laguna Verde Nuclear Plant (LVNP) is presented in this report. The development of the systems mathematical model is based on the response curves of each of its elements. Therefore, little error is expected with respect to real results. On the other hand, due to the fact that the greater part of the systems dynamics is governed by first order differential equations the explicit solution method is used allowing to solve the equations algebraically. The model is validated by comparing real valves and the ones obtained through our model. The analogical and logical parts will be tested considering transitory and steady state situations. The results are presented as computer graphs

  20. Optimal Design and Hybrid Control for the Electro-Hydraulic Dual-Shaking Table System

    Directory of Open Access Journals (Sweden)

    Lianpeng Zhang

    2016-08-01

    Full Text Available This paper is to develop an optimal electro-hydraulic dual-shaking table system with high waveform replication precision. The parameters of hydraulic cylinders, servo valves, hydraulic supply power and gravity balance system are designed and optimized in detail. To improve synchronization and tracking control precision, a hybrid control strategy is proposed. The cross-coupled control using a novel based on sliding mode control based on adaptive reaching law (ASMC, which can adaptively tune the parameters of sliding mode control (SMC, is proposed to reduce the synchronization error. To improve the tracking performance, the observer-based inverse control scheme combining the feed-forward inverse model controller and disturbance observer is proposed. The system model is identified applying the recursive least squares (RLS algorithm and then the feed-forward inverse controller is designed based on zero phase error tracking controller (ZPETC technique. To compensate disturbance and model errors, disturbance observer is used cooperating with the designed inverse controller. The combination of the novel ASMC cross-coupled controller and proposed observer-based inverse controller can improve the control precision noticeably. The dual-shaking table experiment system is built and various experiments are performed. The experimental results indicate that the developed system with the proposed hybrid control strategy is feasible and efficient and can reduce the tracking errors to 25% and synchronization error to 16% compared with traditional control schemes.

  1. Robust Non-Chattering Observer Based Sliding Control Concept for Electro-Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    This paper presents an observer-based sliding mode control concept with chattering reduction, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD's). The proposed control concept requires only common data sheet information and no knowledge on load...... extensive knowledge on system parameters nor advanced control theory. In order to accomplish this task, an integral sliding mode controller designed for the control derivative employing state observation is proposed, based on a generalized reduced order model structure of a VCD with unmatched valve ow......- and cylinder asymmetries. It is shown that limited attention can be given to bounds on parameter estimates, that chattering is reduced and the number of tuning parameters is reduced to the level seen in conventional PID schemes. Furthermore, simulation results demonstrate a high level of robustness when...

  2. Real-time neural network-based self-tuning control of a nonlinear electro-hydraulic servomotor

    Energy Technology Data Exchange (ETDEWEB)

    Canelon, J.I.; Ortega, A.G. [Univ. del Zulia, Maracaibo, Zulia (Venezuela, Bolivarian Republic of). School of Electrical Engineering; Shieh, L.S. [Houston Univ., Houston, TX (United States). Dept. of Electrical and Computer Engineering; Bastidas, J.I. [Univ. del Zulia, Maracaibo, Zulia (Venezuela, Bolivarian Republic of). School of Mechanical Engineering; Zhang, Y.; Akujuobi, C.M. [Prairie View A and M Univ., Prairie View, TX (United States). Center of Excellence for Communication Systems Technology Research and Dept. of Engineering Technology

    2010-08-13

    For high power applications, hydraulic actuators offer many advantages over electromagnetic actuators, including higher torque/mass ratios; smaller control gains; excellent torque capability; filtered high frequency noise; better heat transfer characteristics; smaller size; higher speed of response of the servomechanism; cheaper hardware; and higher reliability. Therefore, any application that requires a large force applied smoothly by an actuator is a candidate for hydraulic power. Examples of such applications include vehicle steering and braking systems; roll mills; drilling rigs; heavy duty crane and presses; and industrial robots and actuators for aircraft control surfaces such as ailerons and flaps. It is extremely important to create effective control strategies for hydraulic systems. This paper outlined the real-time implementation of a neural network-based approach, for self-tuning control of the angular position of a nonlinear electro-hydraulic servomotor. Using an online training algorithm, a neural network autoregressive moving-average model with exogenous input (ARMAX) model of the system was identified and continuously updated and an optimal linear ARMAX model was determined. The paper briefly depicted the neural network-based self-tuning control approach and a description of the experimental equipment (hardware and software) was presented including the implementation details. The experimental results were discussed and conclusions were summarized. It was found that the approach proved to be very effective in the control of this fast dynamics system, outperforming a fine tuned PI controller. Therefore, although the self-tuning approach was computationally demanding, it was feasible for real-time implementation. 22 refs., 6 figs.

  3. Development of a Multi-Arm Mobile Robot for Nuclear Decommissioning Tasks

    Directory of Open Access Journals (Sweden)

    Mohamed J. Bakari

    2008-11-01

    Full Text Available This paper concerns the design of a two-arm mobile delivery platform for application within nuclear decommissioning tasks. The adoption of the human arm as a model of manoeuvrability, scale and dexterity is the starting point for operation of two seven-function arms within the context of nuclear decommissioning tasks, the selection of hardware and its integration, and the development of suitable control methods. The forward and inverse kinematics for the manipulators are derived and the proposed software architecture identified to control the movements of the arm joints and the performance of selected decommissioning tasks. We discuss the adoption of a BROKK demolition machine as a mobile platform and the integration with its hydraulic system to operate the two seven-function manipulators separately. The paper examines the modelling and development of a real-time control method using Proportional-Integral-Derivative (PID and Proportional-Integral-Plus (PIP control algorithms in the host computer with National Instruments functions and tools to control the manipulators and obtain feedback through wireless communication. Finally we consider the application of a third party device, such as a personal mobile phone, and its interface with LabVIEW software in order to operate the robot arms remotely.

  4. Advanced sensor fault detection and isolation for electro-mechanical flight actuators

    OpenAIRE

    Ossmann, Daniel; van der Linden, Franciscus

    2015-01-01

    Moving towards the more electric aircraft to be able to replace mechanic, hydraulic and pneumatic components of an aircraft, the aircraft industry calls for new technologies able to support this trend. One of these technologies is the development of advanced electro-mechanical actuators for aircraft control surfaces. Step by step hydraulic actuators are replaced by their electro-mechanical alternatives featuring weight and cost savings. As hydraulic actuators are used for decades by the air...

  5. Multi-dimensional electro-omosis consolidation of clays

    NARCIS (Netherlands)

    Yuan, J.; Hicks, M.A.; Dijkstra, J.

    2012-01-01

    Electro-osmosis consolidation is an innovative and effective ground improvement method for soft clays. But electro-osmosis is also a very complicated process, as the mechanical behaviour, and hydraulic and electrical properties of the soil are changing rapidly during the treatment process; this

  6. Control system developments for a range of kinematically redundant hydraulic manipulators

    International Nuclear Information System (INIS)

    Smith, A.L.; Rice, P.S.; Thiruarooran, C.

    2000-01-01

    This paper describes a range of control system improvements developed and implemented for in-reactor use during the last three years. Novel control techniques have been developed to provide accurate closed-loop velocity control of pumped hydraulic manipulator joints under a wide range of operating conditions. As a result the supervisory computer system can provide accurate trajectory following, even when more than ten joints are required to move simultaneously. Accurately coordinated motion has given rise to some spectacular gains in in-reactor performance in terms of deployment time, safety and accessibility. The same low-level control improvements have made it feasible to integrate and use the 'geometric controller' to provide accurate resolved motion control of a kinematically redundant manipulator. Examples of recent in-reactor use of all these techniques are given. (author)

  7. Permitting plan for Project W-340, Tank 241-C-106 manipulator retrieval arm

    International Nuclear Information System (INIS)

    Tollefson, K.S.

    1995-01-01

    This document describes the regulatory requirements and describes alternative strategies for obtaining permits and approvals for Project W-340, Tank 241-C-106 Manipulator Retrieval Arm. A comprehensive review of environmental regulations has indicated that several environmental reviews, permits, and approvals are required before design, construction, and operation of the facility. The environmental reviews, permits, and approvals, as well the regulatory authority potentially applicable to the Project W-340 Long Reach Manipulator Arm include the following: National Environmental Policy Act of 1969 -- US Department of Energy, Headquarters; State Environmental Policy Act of 1971 -- State of Washington Department of Ecology; Air Permitting; Dangerous Waste Permitting; Miscellaneous Reviews/Permits/Approvals. This document describes the environmental reviews, permits, and approval requirements for the project. It provides a summary of permit application data requirements, alternative strategies for permit completion and approval, as well as the estimated probability of success for each alternative strategy

  8. A Study of Accuracy and Time Delay for Bilateral Master-Slave Industrial Robotic Arm Manipulator System

    Directory of Open Access Journals (Sweden)

    Mansor Nuratiqa Natrah

    2018-01-01

    Full Text Available Bilateral master-slave industrial robotic arm manipulator system is an advanced technology used to help human to interact with environments that are unreachable to human, due to its remoteness or perilous. The system has been used in different areas such as tele-surgery, autonomous tele-operation for sea and space operation and handling explosive or high radiation operation fields. It is beneficial both for science and society. Remarkably, the system is not common and generally used in Malaysia. Likewise, the number of research conducted that focused about this technology in our country manufacturing industry are not yet discovered and existent. The implementation of this bilateral manipulator system in an industrial robot could be useful for industrial imminent and development over our country and people, specifically for production yield size and human operative. Hence, the study of bilateral robotic arm manipulator system in an industrial robot and analyzation of its performance and time delay in 3 differ controllers will be discussed to attest the efficiency and its effectiveness on the said design system. The experiment conducted was on KUKA youBot arm in V-Rep simulation with three different controllers (P, PD, PID.

  9. On Virtual Integrated Model of a 6DoF Manipulator Arm for Emergency Cases Interventions

    Directory of Open Access Journals (Sweden)

    Gigi Naidin

    2011-09-01

    Full Text Available This research deals with a virtual integrated model for a 6DoF manipulator arm dedicated to use for emergency situations intervention. The virtual model can simulates both the entire structural and mechanical configuration of the manipulator, and the driving system with automated command unit. The basic idea supposes to develop a complex simulator for kinematical and dynamic behavior analysis of 6DoF robot manipulator, and for facilely cross correlation and comparative evaluation between essential parameters and extremely bearing cases defining the manipulator working state. The analysis was developed in Matlab© - SimScape© software. The conclusions dignify the main functional capability of the manipulator supposing the capacity of driving system and mechanical structure.

  10. DESIGN AND STUDY OF DRIVE SWIVEL JOINTS FOR HYDRAULIC MANIPULATION SYSTEMS OF MOBILE TRANSPORT-TECHNOLOGICAL MACHINES

    Directory of Open Access Journals (Sweden)

    Lagerev A.V.

    2018-03-01

    Full Text Available The paper presents the design and principle of operation of a new type of articulated connection of adjacent links of manipulation systems of mobile transport and technological machines – the drive swivel joints to provide a rotary rela-tive movement of the links. Their design allows to combine the function of ensuring the continuity of the kinematic chain and the function of providing rotary movement adjacent units and without the use of additional external devices. The design of the device is protected by a patent of the Russian Federation. Drive swivel joints are an alternative to tra-ditional designs of articulated joints with external power hydraulic drives. Developed a mathematical optimization model. The model is based on the minimization of the mass of the drive swivel joints when you complete the necessary design, installation, operating and strength constraints. Based on this mathematical model the proposed method of com-puter-aided design of the drive swivel joints, which is implemented in a computer program. A study was conducted of the influence of the main technical characteristics and magnitude of the operational load at the optimal weight and the optimal constructive dimensions of the drive swivel joints. It is shown that at equal freight-altitude characteristics of mobile crane-manipulator the drive swivel joint allows you to exclude a number of operational shortcomings of the tra-ditional swivel: 1 development over time of the additional dynamic load of metal due to the increased clearances in connection; 2 lowering the volume of the working area of the crane due to the presence of external power of hydraulic drives; 3 the appearance of cracks due to fatigue failure of the elements of the attachment point of the hydraulic drives to the links of manipulation system. It is possible that the transfer of the hydraulic system for lower operating pressure, which increases the efficiency of the crane and the efficiency of the

  11. A switched energy saving position controller for variable-pressure electro-hydraulic servo systems.

    Science.gov (United States)

    Tivay, Ali; Zareinejad, Mohammad; Rezaei, S Mehdi; Baghestan, Keivan

    2014-07-01

    The electro-hydraulic servo system (EHSS) demonstrates a relatively low level of efficiency compared to other available actuation methods. The objective of this paper is to increase this efficiency by introducing a variable supply pressure into the system and controlling this pressure during the task of position tracking. For this purpose, an EHSS structure with controllable supply pressure is proposed and its dynamic model is derived from the basic laws of physics. A switching control structure is then proposed to control both the supply pressure and the cylinder position at the same time, in a way that reduces the overall energy consumption of the system. The stability of the proposed switching control system is guaranteed by proof, and its performance is verified by experimental testing. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  12. Critical element study on autonomous position control of articulated-arm type manipulator

    International Nuclear Information System (INIS)

    Oka, Kiyoshi; Kakudate, Satoshi; Nakahira, Masataka

    1994-10-01

    An articulated-arm type manipulator can be operated effectively in a restricted space due to its flexibility and it can be attractive for a wide range of in-vessel maintenance such as viewing, inspection and limiter handling in fusion experimental reactors. In case of the in-vessel maintenance using a flexible manipulator, it is quite essential to develop an autonomous control method for compensating a deflection of manipulator so as to minimize the maintenance time with high precision. For this purpose, a new position control method using a combination of neural network predictor with a rigid inverse kinematics is being developed. The key features of this method are to simplify a kinematics modeling of flexible manipulator, to enable quick position compensation in stead of ordinary large matrix compensation, and to be applicable to a wide variety of manipulator characteristics. A sub-scaled model of flexible manipulator with 4 joints has been fabricated for a benchmark experiments of the autonomous position control. Comparing analytical simulation with experiments using the flexible manipulator, it has been demonstrated that the new position control method gives significant improvement in control performance with high precision in order of a figure. In addition, further optimization can be possible by adding other non-linear predictors such as radial basis function and fuzzy modeling. This paper describes the details of a sub-scaled flexible manipulator and a neural network position control system as well as results of analytical simulation and benchmark experiments. (author)

  13. Coordinated Resolved Motion Control of Dual-Arm Manipulators with Closed Chain

    Directory of Open Access Journals (Sweden)

    Tianliang Liu

    2016-05-01

    Full Text Available When applied to some tasks, such as payload handling, assembling, repairing and so on, the two arms of a humanoid robot will form a closed kinematic chain. It makes the motion planning and control for dual-arm coordination very complex and difficult. In this paper, we present three types of resolved motion control methods for a humanoid robot during coordinated manipulation. They are, respectively, position-level, velocity-level and acceleration-level resolved motion control methods. The desired pose, velocity and acceleration of each end-effector are then resolved according to the desired motion of the payload and the constraints on the closed-chain system without consideration of the internal force. Corresponding to the three cases above, the joint variables of each arm are then calculated using the inverse kinematic equations, at position-level, velocity-level or acceleration-level. Finally, a dynamic modelling and simulation platform is established based on ADAMS and Matlab software. The proposed methods are verified by typical cases. The simulation results show that the proposed control strategy can realize the dual-arm coordinated operation and the internal force of the closed chain during the operation is controlled in a reasonable range at the same time.

  14. The evolution of teleoperated manipulators at ORNL

    International Nuclear Information System (INIS)

    Kress, R.L.; Jansen, J.F.; Noakes, M.W.; Herndon, J.N.

    1996-01-01

    ORNL has made significant contributions to teleoperator and telerobotics technology for two decades and continues with an aggressive program today. Examples of past projects are: (1) the M2 servomanipulator, which was the first digitally controlled teleoperator; (2) the Advanced Servomanipulator (ASM), which was the first remotely maintainable teleoperator; (3) the CESARm/Kraft dissimilar teleoperated system; and (4) the Laboratory Telerobotic Manipulator (LTM), a 7-Degree-of-Freedom (7-DOF) telerobot built as a prototype for work in space. More recently, ORNL has become heavily involved with Environmental Restoration and Waste Management (ERWM) robotics programs funded by the Department of Energy (DOE). The ERWM program requires high payloads and high dexterity. As a result, a hydraulically actuated, dual-arm system comprised of two 6-DOF arms mounted on a 5-DOF base has been constructed and is being used today for various research tasks and for decontamination and dismantlement activities. All of these teleoperated manipulator systems build upon the experiences gained throughout the almost two decades of development. Each system incorporates not only the latest technology in computers, sensors, and electronics, but each new . system also adds at least one new feature to the technologies already developed and demonstrated in the previous system(s). As a result of this process, a serious study of these manipulator systems is a study in the evolution of teleoperated manipulator the systems in general. This provides insight not only into the research and development paths chosen in the past, but also into the appropriate directions for future teleoperator and telerobotics research. This paper examines each of the teleoperated/telerobotic systems developed at ORNL, summarizes their features and capabilities, examines the state of the most current telerobotic system (the Dual Arm Work Module), PM provides direction for a Next Generation Telerobotic Manipulator system

  15. Design and characterization of a microelectromechanical system electro-thermal linear motor with interlock mechanism for micro manipulators.

    Science.gov (United States)

    Hu, Tengjiang; Zhao, Yulong; Li, Xiuyuan; Zhao, You; Bai, Yingwei

    2016-03-01

    The design, fabrication, and testing of a novel electro-thermal linear motor for micro manipulators is presented in this paper. The V-shape electro-thermal actuator arrays, micro lever, micro spring, and slider are introduced. In moving operation, the linear motor can move nearly 1 mm displacement with 100 μm each step while keeping the applied voltage as low as 17 V. In holding operation, the motor can stay in one particular position without consuming energy and no creep deformation is found. Actuation force of 12.7 mN indicates the high force generation capability of the device. Experiments of lifetime show that the device can wear over two million cycles of operation. A silicon-on-insulator wafer is introduced to fabricate a high aspect ratio structure and the chip size is 8.5 mm × 8.5 mm × 0.5 mm.

  16. Monitoring and Controlling an Underwater Robotic Arm

    Science.gov (United States)

    Haas, John; Todd, Brian Keith; Woodcock, Larry; Robinson, Fred M.

    2009-01-01

    The SSRMS Module 1 software is part of a system for monitoring an adaptive, closed-loop control of the motions of a robotic arm in NASA s Neutral Buoyancy Laboratory, where buoyancy in a pool of water is used to simulate the weightlessness of outer space. This software is so named because the robot arm is a replica of the Space Shuttle Remote Manipulator System (SSRMS). This software is distributed, running on remote joint processors (RJPs), each of which is mounted in a hydraulic actuator comprising the joint of the robotic arm and communicating with a poolside processor denoted the Direct Control Rack (DCR). Each RJP executes the feedback joint-motion control algorithm for its joint and communicates with the DCR. The DCR receives joint-angular-velocity commands either locally from an operator or remotely from computers that simulate the flight like SSRMS and perform coordinated motion calculations based on hand-controller inputs. The received commands are checked for validity before they are transmitted to the RJPs. The DCR software generates a display of the statuses of the RJPs for the DCR operator and can shut down the hydraulic pump when excessive joint-angle error or failure of a RJP is detected.

  17. Primary reaction control system/remote manipulator system interaction with loaded arm. Space shuttle engineering and operations support

    Science.gov (United States)

    Taylor, E. C.; Davis, J. D.

    1978-01-01

    A study of the interaction between the orbiter primary reaction control system (PRCS) and the remote manipulator system (RMS) with a loaded arm is documented. This analysis was performed with the Payload Deployment and Retrieval Systems Simulation (PDRSS) program with the passive arm bending option. The passive-arm model simulates the arm as massless elastic links with locked joints. The study was divided into two parts. The first part was the evaluation of the response of the arm to step inputs (i.e. constant jet torques) about each of the orbiter body axes. The second part of the study was the evaluation of the response of the arm to minimum impulse primary RCS jet firings with both single pulse and pulse train inputs.

  18. Balanced articulated manipulator

    International Nuclear Information System (INIS)

    Francois, Daniel; Germond, J.-C.; Marchal, Paul; Vertut, Jean.

    1976-01-01

    The description is given of a manipulator of the type comprising a master arm and a slave arm, capable of working in a containment restricted by a wall fitted with an aperture to introduce the slave arm into the containment. According to the invention this manipulator is permanently balanced irrespective of its distortions when it is secured to the wall of the containment in which it is desired to work. The entire manipulator is also balanced when being set up and when moved outside the containment, in relation to a supporting axle. This result is achieved in a simplified manner by giving homothetic shapes to the various component parts of the slave and master arms, the master arm having at least one balancing weight [fr

  19. On the Value of Estimating Human Arm Stiffness during Virtual Teleoperation with Robotic Manipulators.

    Science.gov (United States)

    Buzzi, Jacopo; Ferrigno, Giancarlo; Jansma, Joost M; De Momi, Elena

    2017-01-01

    Teleoperated robotic systems are widely spreading in multiple different fields, from hazardous environments exploration to surgery. In teleoperation, users directly manipulate a master device to achieve task execution at the slave robot side; this interaction is fundamental to guarantee both system stability and task execution performance. In this work, we propose a non-disruptive method to study the arm endpoint stiffness. We evaluate how users exploit the kinetic redundancy of the arm to achieve stability and precision during the execution of different tasks with different master devices. Four users were asked to perform two planar trajectories following virtual tasks using both a serial and a parallel link master device. Users' arm kinematics and muscular activation were acquired and combined with a user-specific musculoskeletal model to estimate the joint stiffness. Using the arm kinematic Jacobian, the arm end-point stiffness was derived. The proposed non-disruptive method is capable of estimating the arm endpoint stiffness during the execution of virtual teleoperated tasks. The obtained results are in accordance with the existing literature in human motor control and show, throughout the tested trajectory, a modulation of the arm endpoint stiffness that is affected by task characteristics and hand speed and acceleration.

  20. On the Value of Estimating Human Arm Stiffness during Virtual Teleoperation with Robotic Manipulators

    Directory of Open Access Journals (Sweden)

    Jacopo Buzzi

    2017-09-01

    Full Text Available Teleoperated robotic systems are widely spreading in multiple different fields, from hazardous environments exploration to surgery. In teleoperation, users directly manipulate a master device to achieve task execution at the slave robot side; this interaction is fundamental to guarantee both system stability and task execution performance. In this work, we propose a non-disruptive method to study the arm endpoint stiffness. We evaluate how users exploit the kinetic redundancy of the arm to achieve stability and precision during the execution of different tasks with different master devices. Four users were asked to perform two planar trajectories following virtual tasks using both a serial and a parallel link master device. Users' arm kinematics and muscular activation were acquired and combined with a user-specific musculoskeletal model to estimate the joint stiffness. Using the arm kinematic Jacobian, the arm end-point stiffness was derived. The proposed non-disruptive method is capable of estimating the arm endpoint stiffness during the execution of virtual teleoperated tasks. The obtained results are in accordance with the existing literature in human motor control and show, throughout the tested trajectory, a modulation of the arm endpoint stiffness that is affected by task characteristics and hand speed and acceleration.

  1. Tension Stiffened and Tendon Actuated Manipulator

    Science.gov (United States)

    Doggett, William R. (Inventor); Dorsey, John T. (Inventor); Ganoe, George G. (Inventor); King, Bruce D. (Inventor); Jones, Thomas C. (Inventor); Mercer, Charles D. (Inventor); Corbin, Cole K. (Inventor)

    2015-01-01

    A tension stiffened and tendon actuated manipulator is provided performing robotic-like movements when acquiring a payload. The manipulator design can be adapted for use in-space, lunar or other planetary installations as it is readily configurable for acquiring and precisely manipulating a payload in both a zero-g environment and in an environment with a gravity field. The manipulator includes a plurality of link arms, a hinge connecting adjacent link arms together to allow the adjacent link arms to rotate relative to each other and a cable actuation and tensioning system provided between adjacent link arms. The cable actuation and tensioning system includes a spreader arm and a plurality of driven and non-driven elements attached to the link arms and the spreader arm. At least one cable is routed around the driven and non-driven elements for actuating the hinge.

  2. An energy-saving nonlinear position control strategy for electro-hydraulic servo systems.

    Science.gov (United States)

    Baghestan, Keivan; Rezaei, Seyed Mehdi; Talebi, Heidar Ali; Zareinejad, Mohammad

    2015-11-01

    The electro-hydraulic servo system (EHSS) demonstrates numerous advantages in size and performance compared to other actuation methods. Oftentimes, its utilization in industrial and machinery settings is limited by its inferior efficiency. In this paper, a nonlinear backstepping control algorithm with an energy-saving approach is proposed for position control in the EHSS. To achieve improved efficiency, two control valves including a proportional directional valve (PDV) and a proportional relief valve (PRV) are used to achieve the control objectives. To design the control algorithm, the state space model equations of the system are transformed to their normal form and the control law through the PDV is designed using a backstepping approach for position tracking. Then, another nonlinear set of laws is derived to achieve energy-saving through the PRV input. This control design method, based on the normal form representation, imposes internal dynamics on the closed-loop system. The stability of the internal dynamics is analyzed in special cases of operation. Experimental results verify that both tracking and energy-saving objectives are satisfied for the closed-loop system. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  3. Modal space three-state feedback control for electro-hydraulic servo plane redundant driving mechanism with eccentric load decoupling.

    Science.gov (United States)

    Zhao, Jinsong; Wang, Zhipeng; Zhang, Chuanbi; Yang, Chifu; Bai, Wenjie; Zhao, Zining

    2018-06-01

    The shaking table based on electro-hydraulic servo parallel mechanism has the advantage of strong carrying capacity. However, the strong coupling caused by the eccentric load not only affects the degree of freedom space control precision, but also brings trouble to the system control. A novel decoupling control strategy is proposed, which is based on modal space to solve the coupling problem for parallel mechanism with eccentric load. The phenomenon of strong dynamic coupling among degree of freedom space is described by experiments, and its influence on control design is discussed. Considering the particularity of plane motion, the dynamic model is built by Lagrangian method to avoid complex calculations. The dynamic equations of the coupling physical space are transformed into the dynamic equations of the decoupling modal space by using the weighted orthogonality of the modal main mode with respect to mass matrix and stiffness matrix. In the modal space, the adjustments of the modal channels are independent of each other. Moreover, the paper discusses identical closed-loop dynamic characteristics of modal channels, which will realize decoupling for degree of freedom space, thus a modal space three-state feedback control is proposed to expand the frequency bandwidth of each modal channel for ensuring their near-identical responses in a larger frequency range. Experimental results show that the concept of modal space three-state feedback control proposed in this paper can effectively reduce the strong coupling problem of degree of freedom space channels, which verify the effectiveness of the proposed model space state feedback control strategy for improving the control performance of the electro-hydraulic servo plane redundant driving mechanism. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    2005-01-01

    The paper presents research results using IT-Tools for CAD and dynamic modelling, simulation, analysis, and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. Matlab/Simulink and CATIA are used as IT-Tools. The contributions include results from on......-going research projects on fluid power and mechatronics based on tap water hydraulic servovalves and linear servo actuators and rotary vane actuators for motion control and power transmission. Development and design a novel water hydraulic rotary vane actuator for robot manipulators. Proposed mathematical...... modelling, control and simulation of a water hydraulic rotary vane actuator applied to power and control a two-links manipulator and evaluate performance. The results include engineering design and test of the proposed simulation models compared with IHA Tampere University’s presentation of research...

  5. Multi-objective optimization of the control strategy of electric vehicle electro-hydraulic composite braking system with genetic algorithm

    Directory of Open Access Journals (Sweden)

    Zhang Fengjiao

    2015-03-01

    Full Text Available Optimization of the control strategy plays an important role in improving the performance of electric vehicles. In order to improve the braking stability and recover the braking energy, a multi-objective genetic algorithm is applied to optimize the key parameters in the control strategy of electric vehicle electro-hydraulic composite braking system. Various limitations are considered in the optimization process, and the optimization results are verified by a software simulation platform of electric vehicle regenerative braking system in typical brake conditions. The results show that optimization objectives achieved a good astringency, and the optimized control strategy can increase the brake energy recovery effectively under the condition of ensuring the braking stability.

  6. Hydraulic shock absorbers

    International Nuclear Information System (INIS)

    Thatcher, G.; Davidson, D. F.

    1984-01-01

    A hydraulic shock absorber of the dash pot kind for use with electrically conducting liquid such as sodium, has magnet means for electro magnetically braking a stream of liquid discharged from the cylinder. The shock absorber finds use in a liquid metal cooled nuclear reactor for arresting control rods

  7. Control issues for a hydraulically powered dissimilar teleoperated system

    International Nuclear Information System (INIS)

    Jansen, J.F.; Kress, R.L.

    1995-01-01

    This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented. (Schilling's Titan II hydraulic manipulators are the slave manipulators and the master manipulators are from the Oak Ridge National Laboratory-developed Advanced Servo Manipulator.)

  8. Assessment of a water hydraulics joint for RH operations in the divertor region

    International Nuclear Information System (INIS)

    Dubus, G.; David, O.; Measson, Y.; Friconneau, J.P.

    2007-01-01

    Due to the high level of radiations, all the nominal maintenance in the divertor region of ITER will be carried out with help of robotic means. In reduced volumes, hydraulic applications can provide powerful actuators. They become an interesting technology to build a heavy duty manipulator for operations in space constrained areas. Oil hydraulics can not ensure the cleanliness level required for all maintenance operations in the vacuum vessel. Therefore, pure water hydraulics proposes a good alternative to oil and developments are today focusing on that direction. Although basic hydraulic elements like pumps, on-off valves, filters running with pure water are already available on the market, actuators are not so many and generally limited to linear motions. Fine control of the joint is achieved with help of servovalves. Today's off the shelf products are only adaptations from standard oil servovalves and are not specifically designed for water use. Operational experience for these products shows short lifetime expectancy and could not last a complete shutdown. Starting from the oil hydraulic version CEA with help of Cybernetix redesigned for water applications the elbow vane actuator of a Maestro arm, a six-degrees-of-freedom hydraulic manipulator used in decommissioning activities. In parallel with help of In-LHC, CEA developed a servovalve for water hydraulic applications that fits the space constraints of a Maestro manipulator. This prototype is a pressure-control valve. To a current input this servovalve supplies a very accurate pressure difference output instead of a flow rate in the case of flow control servovalve that are generally used in that kind of applications. The advantage is the improvement of the performances and stability of the force control loop. This paper presents the performances of the modified vane actuator and its servovalve. Both static and dynamic responses of the servovalve prototype with and without actuator are presented. Position and

  9. Performance of an Electro-Hydrostatic Actuator on the F-18 Systems Research Aircraft

    Science.gov (United States)

    Navarro, Robert

    1997-01-01

    An electro-hydrostatic actuator was evaluated at NASA Dryden Flight Research Center, Edwards, California. The primary goal of testing this actuator system was the flight demonstration of power-by-wire technology on a primary flight control surface. The electro-hydrostatic actuator uses an electric motor to drive a hydraulic pump and relies on local hydraulics for force transmission. This actuator replaced the F-18 standard left aileron actuator on the F-18 Systems Research Aircraft and was evaluated throughout the Systems Research Aircraft flight envelope. As of July 24, 1997 the electro-hydrostatic actuator had accumulated 23.5 hours of flight time. This paper presents the electro-hydrostatic actuator system configuration and component description, ground and flight test plans, ground and flight test results, and lessons learned. This actuator performs as well as the standard actuator and has more load capability than required by aileron actuator specifications of McDonnell- Douglas Aircraft, St. Louis, Missouri. The electro-hydrostatic actuator system passed all of its ground tests with the exception of one power-off test during unloaded dynamic cycling.

  10. Manipulators

    International Nuclear Information System (INIS)

    Wilcock, P.D.

    1984-01-01

    The patent concerns a manipulator, which enables operations to be carried out remotely from the operator. The device is suitable for use in handling of radioactive materials and other hazardous liquids or gases. The specifications are given, and the movements of the manipulator arm described. (U.K.)

  11. Sliding Control with Chattering Elimination for Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2012-01-01

    This paper presents the development of a sliding mode control scheme with chattering elimination, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives. The proposed control scheme requires only common data sheet information, no knowledge on load characteri......This paper presents the development of a sliding mode control scheme with chattering elimination, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives. The proposed control scheme requires only common data sheet information, no knowledge on load...... controller is developed for the control derivative based on a reduced order model. Simulation results demonstrate strong robustness when subjected to parameter perturbations and that chattering is eliminated....

  12. A manipulator

    International Nuclear Information System (INIS)

    Cole, G.V.; Hofmann, D.A.; Ashby, R.

    1984-01-01

    A manipulator is described, for remote handling of objects within an enclosure, by an operator outside the enclosure. The manipulator consists of a telescopically extensible arm member, the action of which is controlled by a motor-driven lead screw. (U.K.)

  13. Analysis of singularity in redundant manipulators

    International Nuclear Information System (INIS)

    Watanabe, Koichi

    2000-03-01

    In the analysis of arm positions and configurations of redundant manipulators, the singularity avoidance problems are important themes. This report presents singularity avoidance computations of a 7 DOF manipulator by using a computer code based on human-arm models. The behavior of the arm escaping from the singular point can be identified satisfactorily through the use of 3-D plotting tools. (author)

  14. Remote control manipulator

    Energy Technology Data Exchange (ETDEWEB)

    Sugawara, T

    1970-02-28

    A prior-art remote control manipulator comprises a horizontal suspension section, a master arm and a slave arm which are coupled to ends of the suspension section in a manner to pivotally move relative to the suspension section, and a connecting device which includes a tape and which joins both the arms. When the connecting device malfunctions, the slave arm can neither be extended nor contracted. Means to keep the tension of the tape is required which restricts the extension length of the slave arm. Further, the slave arm can be moved only in the axial direction. The invention described provides an improved remote control manipulator of the specified type. A moving device which moves the slave arm relative to the master arm without the intervention of the connecting device is mounted on a movable part of the slave arm, while pulleys which maintain the joining relationship of the connecting device are mounted on the movable part and fixed part of the slave arm. Owing to this construction, movement of the slave arm is assured despite troubles which may arise in the connecting device. In addition, no slack arises in the tape. By applying a similar construction to the horizontal suspension section, the suspension section can be stretched, and hence, the slave arm can be moved in a direction orthogonal to its axis.

  15. Assessment of a water hydraulics joint for RH operations in the divertor region

    Energy Technology Data Exchange (ETDEWEB)

    Dubus, G.; David, O.; Measson, Y.; Friconneau, J.P. [CEA LIST, Interactive Robotics Unit (France)

    2007-07-01

    Due to the high level of radiations, all the nominal maintenance in the divertor region of ITER will be carried out with help of robotic means. In reduced volumes, hydraulic applications can provide powerful actuators. They become an interesting technology to build a heavy duty manipulator for operations in space constrained areas. Oil hydraulics can not ensure the cleanliness level required for all maintenance operations in the vacuum vessel. Therefore, pure water hydraulics proposes a good alternative to oil and developments are today focusing on that direction. Although basic hydraulic elements like pumps, on-off valves, filters running with pure water are already available on the market, actuators are not so many and generally limited to linear motions. Fine control of the joint is achieved with help of servovalves. Today's off the shelf products are only adaptations from standard oil servovalves and are not specifically designed for water use. Operational experience for these products shows short lifetime expectancy and could not last a complete shutdown. Starting from the oil hydraulic version CEA with help of Cybernetix redesigned for water applications the elbow vane actuator of a Maestro arm, a six-degrees-of-freedom hydraulic manipulator used in decommissioning activities. In parallel with help of In-LHC, CEA developed a servovalve for water hydraulic applications that fits the space constraints of a Maestro manipulator. This prototype is a pressure-control valve. To a current input this servovalve supplies a very accurate pressure difference output instead of a flow rate in the case of flow control servovalve that are generally used in that kind of applications. The advantage is the improvement of the performances and stability of the force control loop. This paper presents the performances of the modified vane actuator and its servovalve. Both static and dynamic responses of the servovalve prototype with and without actuator are presented. Position

  16. Task-oriented control of Single-Master Multi-Slave Manipulator System

    International Nuclear Information System (INIS)

    Kosuge, Kazuhiro; Ishikawa, Jun; Furuta, Katsuhisa; Hariki, Kazuo; Sakai, Masaru.

    1994-01-01

    A master-slave manipulator system, in general, consists of a master arm manipulated by a human and a slave arm used for real tasks. Some tasks, such as manipulation of a heavy object, etc., require two or more slave arms operated simultaneously. A Single-Master Multi-Slave Manipulator System consists of a master arm with six degrees of freedom and two or more slave arms, each of which has six or more degrees of freedom. In this system, a master arm controls the task-oriented variables using Virtual Internal Model (VIM) based on the concept of 'Task-Oriented Control'. VIM is a reference model driven by sensory information and used to describe the desired relation between the motion of a master arm and task-oriented variables. The motion of slave arms are controlled based on the task oriented variables generated by VIM and tailors the system to meet specific tasks. A single-master multi-slave manipulator system, having two slave arms, is experimentally developed and illustrates the concept. (author)

  17. Robotic-Movement Payload Lifter and Manipulator

    Science.gov (United States)

    Doggett, William R. (Inventor); King, Bruce D. (Inventor); Collins, Timothy J. (Inventor); Dorsey, John T. (Inventor)

    2011-01-01

    A payload lifter/manipulator module includes a rotatable joint supporting spreader arms angularly spaced with respect to one another. A rigid arm is fixedly coupled to the joint and extends out therefrom to a tip. A tension arm has a first end and a second end with the first end being fixedly coupled to the tip of the rigid arm. The tension arm incorporates pivots along the length thereof. Each pivot can be engaged by or disengaged from the outboard end of a spreader arm based on a position of the spreader arm. A hoist, positioned remotely with respect to the module and coupled to the second end of the tension arm, controls the position of the spreader arms to thereby control the position of the rigid arm's tip. Payload lifter/manipulator assemblies can be constructed with one or more of the modules.

  18. Research on a Nonlinear Robust Adaptive Control Method of the Elbow Joint of a Seven-Function Hydraulic Manipulator Based on Double-Screw-Pair Transmission

    Directory of Open Access Journals (Sweden)

    Gaosheng Luo

    2014-01-01

    Full Text Available A robust adaptive control method with full-state feedback is proposed based on the fact that the elbow joint of a seven-function hydraulic manipulator with double-screw-pair transmission features the following control characteristics: a strongly nonlinear hydraulic system, parameter uncertainties susceptible to temperature and pressure changes of the external environment, and unknown outer disturbances. Combined with the design method of the back-stepping controller, the asymptotic stability of the control system in the presence of disturbances from uncertain systematic parameters and unknown external disturbances was demonstrated using Lyapunov stability theory. Based on the elbow joint of the seven-function master-slave hydraulic manipulator for the 4500 m Deep-Sea Working System as the research subject, a comparative study was conducted using the control method presented in this paper for unknown external disturbances. Simulations and experiments of different unknown outer disturbances showed that (1 the proposed controller could robustly track the desired reference trajectory with satisfactory dynamic performance and steady accuracy and that (2 the modified parameter adaptive laws could also guarantee that the estimated parameters are bounded.

  19. Layout of the manipulator-arm (boom) for the TFTR fusion reactor (Princeton, USA) under UHV-conditions

    International Nuclear Information System (INIS)

    Klaubert, J.

    1987-01-01

    This presentation shows the main criteria for the layout of the manipulator - arm and the antechamber - vessel of the TFTR - FUSION - REACTOR at Princeton University, PLASMA PHYSICS LABORATORY (USA). The main problem during layout of a manipulator system like the TFTR - Boom has been the limitation of the vertical deflections due to deadweight of the construction. The design problem is rather a deformation problem and a problem of stability than a stress problem. The way of optimizing the ratio between stiffness and deadweight is the most important part during the complete design - process. Additional earthquake requirements need further investigations for a satisfying layout (horizontal forces, weak-axis of moment of inertia). The details of the construction (welding, connections etc.) have to be designed in respect to UHV - requirements --> no holes and no fillet welds (outgasing - rate.) are allowed. All weldings have to be designed as bevel-welds. This manipulator system is designed for working in a plane system (two degrees of freedom). A manipulator system with the same operating capabilities in a three degree of freedom system needs larger cross sections for the different beam-elements than those of the discussed TFTR - BOOM

  20. Pressure control valve using proportional electro-magnetic solenoid actuator

    International Nuclear Information System (INIS)

    Yun, So Nam; Ham, Young Bog; Park, Pyoung Won

    2006-01-01

    This paper presents an experimental characteristics of electro-hydraulic proportional pressure control valve. In this study, poppet and valve body which are assembled into the proportional solenoid were designed and manufactured. The constant force characteristics of proportional solenoid actuator in the control region should be independent of the plunger position in order to be used to control the valve position in the fluid flow control system. The stroke-force characteristics of the proportional solenoid actuator is determined by the shape (or parameters) of the control cone. In this paper, steady state and transient characteristics of the solenoid actuator for electro-hydraulic proportional valve are analyzed using finite element method and it is confirmed that the proportional solenoid actuator has a constant attraction force in the control region independently on the stroke position. The effects of the parameters such as control cone length, thickness and taper length are also discussed

  1. Manipulators for production and research

    International Nuclear Information System (INIS)

    Munro, Ian

    1987-01-01

    The development of caves or cells and master-slave manipulators to handle radioactive materials is discussed. Some of the most recent advances are described. A manipulator arm, a master-slave manipulator and a servomanipulator mounted on a manipulator are illustrated. Future developments are discussed - these include resolved tip control for the manipulator. (UK)

  2. Control of master-slave manipulator using virtual force

    International Nuclear Information System (INIS)

    Kosuge, Kazuhiro; Fukuda, Toshio; Itoh, Tomotaka; Sakamoto, Keizoh; Noma, Yasuo.

    1994-01-01

    We propose a control system for a master-slave manipulator system having a rate-controlled slave manipulator. In this system, the master manipulator is stiffness-controlled in the Cartesian coordinate system, and the slave manipulator is damping-controlled in the Cartesian coordinate system. The desired velocity of the slave arm is given by a displacement of the master arm from a nominal position. The operator feels virtual contact force from the environment because the contact force is proportional to the displacement when the slave arm motion is constrained by the environment. The proposed method is experimentally applied to manipulators with three degrees of freedom. The experimental results illustrate the validity of the proposed system. (author)

  3. In-cell maintenance by manipulator arm with 3D workspace information recreated by laser rangefinder

    International Nuclear Information System (INIS)

    Kitamura, Akihiro; Nakai, Koji; Namekawa, Takashi; Watahiki, Masatoshi

    2011-01-01

    Highlights: → We developed a remote control system for maintenance of in-cell type fuel fabrication equipment. → The system display recreated three-dimensional information of the workspace from data obtained by laser rangefinder and conventional cameras. It has allowed us to operate a manipulator arm remotely with several control modes. → We implemented remote handling experiments using mock up equipment. Performance was compared for remote operation conducted using several different display and operation modes. → It was observed that integration of 3D information from the laser rangefinder reduced operation time and reinforced visual information during remote operation. - Abstract: We developed a remote control system for maintenance of in-cell type fuel fabrication equipment. The system display recreated three-dimensional information of the workspace from data obtained by laser rangefinder and conventional cameras. It has allowed us to operate a manipulator arm remotely with several control modes. In order to evaluate the effectiveness and usefulness of developed system, we implemented remote handling experiments using mock up equipment. Performance was compared for remote operation conducted using several different display and operation modes. We confirmed that the system is able to maintain in-cell fuel fabrication equipment in each display and operation mode. Times required to complete the remote operations were collected and compared in each mode. It was observed that integration of 3D information from the laser rangefinder reduced operation time and reinforced visual information during remote operation.

  4. SAMSIN: the next-generation servo-manipulator

    International Nuclear Information System (INIS)

    Adams, R.H.; Jennrich, C.E.; Korpi, K.W.

    1985-01-01

    The Central Research Laboratories (CRL) Division of Sargent Industries is now developing SAMSIN, a next-generation servo-manipulator. SAMSIN is an acronym for Servo-Actuated Manipulator Systems with Intelligent Networks. This paper discusses the objectives of this development and describes the key features of the servo-manipulator system. There are three main objectives in the SAMSIN development: adaptability, reliability, and maintainability. SAMSIN utilizes standard Sargent/CRL sealed master and slave manipulator arms as well as newly developed compact versions. The mechanical arms have more than 20 yr of successful performance in industrial applications such as hot cells, high vacuums, fuel pools, and explosives handling. The servo-actuator package is in a protective enclosure, which may be sealed in various ways from the remote environment. The force limiting characteristics of the servo-actuators extend motion tendon life. Protective bootings increase the reliability of the arms in an environment that is high in airborne contamination. These bootings also simplify the decontamination of the system. The modularity in construction permits quick removal and replacement of slave arms, wrist joints, tong fingers, and actuator packages for maintenance. SAMSIN utilizes readily available off-the-shelf actuator and control system components. Each manipulator motion uses the same actuator and control system components

  5. SNAKES manipulator and ARD sluicer testing - April 1997

    International Nuclear Information System (INIS)

    Berglin, E.J.

    1997-01-01

    Long reach arms represent one of the options available for deployment of end effectors which can be used in the retrieval of radioactive waste, from the Hanford single shell tanks. The versatility of an arm based deployment system is such that it has the potential to improve the performance of a wide range of end effectors compared with stand-alone or other deployment methods. The long term reliability and availability of the deployment system is central to the timely completion of a waste retrieval program. However, concerns have been expressed over the dynamic performance of long reach arms and it is essential that an arm based system can cope with operational dynamic loads generated by end effectors. The test program conducted set out to measure static and dynamic loads and responses from a representative arm and sluicer, with the objective of extrapolating the data to a long reach arm system, that can be used for in-tank waste retrieval. As an arm with an appropriate reach was not available, the test program was undertaken to measure dynamic characteristics of a Magnox Electric 18 ft multi-link, hydraulically actuated SNAKES manipulator. This is the longest reach unit in service, albeit only one third of the 50 ft length required for in-tank waste retrieval. In addition operational performance and loading measurements were obtained from a low pressure confined system sluicer under development by ARD Environmental, to add to the end effector data base. When subject to impulse loading, the arm was found to behave in a repeatable manner having fundamental natural frequencies in the vertical and transverse directions of 1 Hz. There were also a large number of higher natural frequencies measured up to 100 Hz

  6. Master-slave type manipulator

    International Nuclear Information System (INIS)

    Haaker, L.W.; Jelatis, D.G.

    1979-01-01

    Remote control manipulator of the master-slave type for carrying out work on the other side of a shield wall. This appliance allows a Y movement relative displacement, the function of which is to extend the range of the manipulator towards the front and also to facilitate its installation, the lateral rotation or inclination of the slave arm in relation to the master arm, and the Z movement extension through which the length of the slave arm is increased in comparison with that of the master arm. Devices have been developed which transform the linear movements into rotational movements to enable these movements to be transmitted through rotational seal fittings capable of ensuring the safety of the separation between the operator's environment and that in the work area. Particular improvements have been made to the handles, handle seals, pincer mechanisms, etc [fr

  7. Progress in Nano-Electro-Optics III Industrial Applications and Dynamics of the Nano-Optical System

    CERN Document Server

    Ohtsu, Motoichi

    2005-01-01

    This unique monograph series "Progress in Nano-Electro Optics" reviews the results of advanced studies of electro-optics on the nanometric scale. This third volume covers the most recent topics of theoretical and experimental interest including classical and quantum optics, organic and inorganic material science and technology, surface science, spectroscopy, atom manipulation, photonics, and electronics. Each chapter is written by one or more leading scientists from the relevant field. Thus, high-quality scientific and technical information is provided to scientists, engineers, and students engaged in nano-electro optics and nanophotonics research. The first two volumes addressed the "Basics and Theory of Near Field Optics" (2002) and "Novel Devices and Atom Manipulation" (2003).

  8. Impacts of long-term precipitation manipulation on hydraulic architecture and xylem anatomy of piñon and juniper in Southwest USA.

    Science.gov (United States)

    Hudson, P J; Limousin, J M; Krofcheck, D J; Boutz, A L; Pangle, R E; Gehres, N; McDowell, N G; Pockman, W T

    2018-02-01

    Hydraulic architecture imposes a fundamental control on water transport, underpinning plant productivity, and survival. The extent to which hydraulic architecture of mature trees acclimates to chronic drought is poorly understood, limiting accuracy in predictions of forest responses to future droughts. We measured seasonal shoot hydraulic performance for multiple years to assess xylem acclimation in mature piñon (Pinus edulis) and juniper (Juniperus monosperma) after 3+ years of precipitation manipulation. Our treatments consisted of water addition (+20% ambient precipitation), partial precipitation-exclusion (-45% ambient precipitation), and exclusion-structure control. Supplemental watering elevated leaf water potential, sapwood-area specific hydraulic conductivity, and leaf-area specific hydraulic conductivity relative to precipitation exclusion. Shifts in allocation of leaf area to sapwood area enhanced differences between irrigated and droughted K L in piñon but not juniper. Piñon and juniper achieved similar K L under ambient conditions, but juniper matched or outperformed piñon in all physiological measurements under both increased and decreased precipitation treatments. Embolism vulnerability and xylem anatomy were unaffected by treatments in either species. Absence of significant acclimation combined with inferior performance for both hydraulic transport and safety suggests piñon has greater risk of local extirpation if aridity increases as predicted in the southwestern USA. © 2017 John Wiley & Sons Ltd.

  9. Hydraulics and pneumatics a technician's and engineer's guide

    CERN Document Server

    Parr, Andrew

    2011-01-01

    Nearly all industrial processes require objects to be moved, manipulated or subjected to some sort of force. Such movements and manipulations are frequently accomplished by means of devices driven by liquids (hydraulics) or air (pneumatics), the subject of this book. Hydraulics and Pneumatics is written by a practicing process control engineer as a guide to the successful operation of hydraulic and pneumatic systems for all engineers and technicians working with them. Keeping mathematics and theory to a minimum, this practical guide is thorough but accessible to technicians without a

  10. Finite-time adaptive sliding mode force control for electro-hydraulic load simulator based on improved GMS friction model

    Science.gov (United States)

    Kang, Shuo; Yan, Hao; Dong, Lijing; Li, Changchun

    2018-03-01

    This paper addresses the force tracking problem of electro-hydraulic load simulator under the influence of nonlinear friction and uncertain disturbance. A nonlinear system model combined with the improved generalized Maxwell-slip (GMS) friction model is firstly derived to describe the characteristics of load simulator system more accurately. Then, by using particle swarm optimization (PSO) algorithm ​combined with the system hysteresis characteristic analysis, the GMS friction parameters are identified. To compensate for nonlinear friction and uncertain disturbance, a finite-time adaptive sliding mode control method is proposed based on the accurate system model. This controller has the ability to ensure that the system state moves along the nonlinear sliding surface to steady state in a short time as well as good dynamic properties under the influence of parametric uncertainties and disturbance, which further improves the force loading accuracy and rapidity. At the end of this work, simulation and experimental results are employed to demonstrate the effectiveness of the proposed sliding mode control strategy.

  11. Concrete decontamination by electro-hydraulic scabbling (EHS). Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-01

    Contamination of concrete structures by radionuclides, hazardous metals and organic substances (including PCB`s) occurs at many DOE sites. The contamination of concrete structures (walls, floors, ceilings, etc.) varies in type, concentration, and especially depth of penetration into the concrete. In many instances, only the surface layer of concrete is contaminated, up to a depth of one inch, according to estimates provided in the R and D ID document. Then, removal of the concrete surface layer (scabbling) is considered to be the most effective decontamination method. Textron Systems Corp. (TSC) has developed a scabbling concept based on electro-mechanical phenomena accompanying strong electric pulses generated by applying high voltage at the concrete/water interface. Depending on the conditions, the electric discharge may occur either through a waste layer or through the concrete body itself. This report describes the development, testing, and results of this electro-mechanical process. Phase 1 demonstrated the feasibility of the process for the controlled removal of a thin layer of contaminated concrete. Phase 2 designed, fabricated, and tested an integrated subscale unit. This was tested at Fernald. In Phase 3, the scabbling unit was reconfigured to increase its power and processing rate. Technology transfer to an engineering contracting company is continuing.

  12. Concrete decontamination by electro-hydraulic scabbling (EHS). Final report

    International Nuclear Information System (INIS)

    1997-10-01

    Contamination of concrete structures by radionuclides, hazardous metals and organic substances (including PCB's) occurs at many DOE sites. The contamination of concrete structures (walls, floors, ceilings, etc.) varies in type, concentration, and especially depth of penetration into the concrete. In many instances, only the surface layer of concrete is contaminated, up to a depth of one inch, according to estimates provided in the R and D ID document. Then, removal of the concrete surface layer (scabbling) is considered to be the most effective decontamination method. Textron Systems Corp. (TSC) has developed a scabbling concept based on electro-mechanical phenomena accompanying strong electric pulses generated by applying high voltage at the concrete/water interface. Depending on the conditions, the electric discharge may occur either through a waste layer or through the concrete body itself. This report describes the development, testing, and results of this electro-mechanical process. Phase 1 demonstrated the feasibility of the process for the controlled removal of a thin layer of contaminated concrete. Phase 2 designed, fabricated, and tested an integrated subscale unit. This was tested at Fernald. In Phase 3, the scabbling unit was reconfigured to increase its power and processing rate. Technology transfer to an engineering contracting company is continuing

  13. Modeling and controller design on ARX model of Electro-Hydrolic ...

    African Journals Online (AJOL)

    Electro-hydraulic actuator (EHA) is commonly used in industry for its linear movement, quick response and accurate positioning of heavy loads. However, the uncertainties, highly nonlinearities and time varying characteristic of EHA caused difficulties in controlling the system. This paper studies the performance of Fuzzy PID ...

  14. Hydrogel Walkers with Electro-Driven Motility for Cargo Transport.

    Science.gov (United States)

    Yang, Chao; Wang, Wei; Yao, Chen; Xie, Rui; Ju, Xiao-Jie; Liu, Zhuang; Chu, Liang-Yin

    2015-08-28

    In this study, soft hydrogel walkers with electro-driven motility for cargo transport have been developed via a facile mould-assisted strategy. The hydrogel walkers consisting of polyanionic poly(2-acrylamido-2-methylpropanesulfonic acid-co-acrylamide) exhibit an arc looper-like shape with two "legs" for walking. The hydrogel walkers can reversibly bend and stretch via repeated "on/off" electro-triggers in electrolyte solution. Based on such bending/stretching behaviors, the hydrogel walkers can move their two "legs" to achieve one-directional walking motion on a rough surface via repeated "on/off" electro-triggering cycles. Moreover, the hydrogel walkers loaded with very heavy cargo also exhibit excellent walking motion for cargo transport. Such hydrogel systems create new opportunities for developing electro-controlled soft systems with simple design/fabrication strategies in the soft robotic field for remote manipulation and transportation.

  15. Master-slave manipulator

    International Nuclear Information System (INIS)

    Haaker, L.W.; Jelatis, D.G.

    1981-01-01

    A remote control master-slave manipulator for performing work on the opposite side of a barrier wall, is described. The manipulator consists of a rotatable horizontal support adapted to extend through the wall and two longitudinally extensible arms, a master and a slave, pivotally connected one to each end of the support. (U.K.)

  16. Stainless steel decontamination manipulators

    International Nuclear Information System (INIS)

    Sullivan, R.J.

    1986-01-01

    Three, large-volume coverage manipulator systems were designed and built for the Defense Water Processing Facility at the Savannah River Laboratory. These stainless steel systems will be used for high-pressure spray decontamination of waste containers and large process equipment modules. Each system has a manipulator arm, folding boom, and vertical drive and guide structure. Handling capacity is 45 kg, horizontal reach is 4.6 m with a 180-deg swing motion, and the vertical travel is 6 m. The system is remotely removable and replaceable in modules using an overhead crane and an impact wrench. The manipulator arm has seven motions: Shoulder rotation and pivot, elbow pivot, wrist pivot and rotation, and grip open-close. All motions are variable speed and are slip-clutch protected to prevent overloading from external forces (collisions)

  17. A 3D steady-state model of a tendon-driven continuum soft manipulator inspired by the octopus arm

    International Nuclear Information System (INIS)

    Renda, F; Cianchetti, M; Giorelli, M; Arienti, A; Laschi, C

    2012-01-01

    Control and modelling of continuum robots are challenging tasks for robotic researchers. Most works on modelling are limited to piecewise constant curvature. In many cases they neglect to model the actuators or avoid a continuum approach. In particular, in the latter case this leads to a complex model hardly implemented. In this work, a geometrically exact steady-state model of a tendon-driven manipulator inspired by the octopus arm is presented. It takes a continuum approach, fast enough to be implemented in the control law, and includes a model of the actuation system. The model was experimentally validated and the results are reported. In conclusion, the model presented can be used as a tool for mechanical design of continuum tendon-driven manipulators, for planning control strategies or as internal model in an embedded system. (paper)

  18. A low order adaptive control scheme for hydraulic servo systems

    DEFF Research Database (Denmark)

    Andersen, Torben Ole; Pedersen, Henrik Clemmensen; Bech, Michael Møller

    2015-01-01

    This paper deals with high-performance position control of hydraulics servo systems in general. The hydraulic servo system used is a two link robotic manipulator actuated by two hydraulic servo cylinders. A non-linear model of the hydraulic system and a Newton-Euler based model of the mechanical...

  19. The TFTR maintenance manipulator

    International Nuclear Information System (INIS)

    Kungl, D.; Loesser, D.; Heitzenroeder, P.; Cerdan, G.

    1989-01-01

    TFTR plans to begin D-T experiments in mid 1990. The D-T experimental program will produce approximately one hundred shots, with a neutron generation rate of 10 19 neutrons per shot. This will result in high levels of activation in TFTR, especially in the vacuum vessel. The primary purpose of the Maintenance Manipulator is to provide a means of remotely performing certain defined maintenance and inspection tasks inside the vacuum torus so as to minimize personnel exposure to radiation. The manipulator consists of a six-link folding boom connected to a fixed boom on a movable carriage. The entire manipulator is housed in a vacuum antechamber connected to the vacuum torus, through a port formerly used for a vacuum pumping duct. The configuration extends 180 0 in either direction to provide complete coverage of the torus. The four 3500 l/s turbopumps which were formerly used in the pumping duct will be mounted on the antechamber. The manipulator will utilize two end effectors. The first, called a General Inspection Arm (GIA) provides a movable platform to an inspection camera and an in-vacuum leak detector. The second is a bilateral, force-reflecting pair of slave arms which utilize specially developed tools to perform several maintenance functions. All components except the slave arms are capable of operating in TFTR's vacuum environment and during 150 0 C bakeout of the torus. (orig.)

  20. Analysis of and H∞ Controller Design For An Electro-Hydraulic Servo Pressure Regulator

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole

    2011-01-01

    -circuit pumps are still hydraulically controlled, there is however still a need for being able to generate a hydraulic pilot pressure. The focus of the current paper is on the analysis and controller design of an electrohydraulic servo pressure regulator, which generates a hydraulic LS-pressure for a variable...

  1. Fuzzy robust nonlinear control approach for electro-hydraulic flight motion simulator

    Directory of Open Access Journals (Sweden)

    Han Songshan

    2015-02-01

    Full Text Available A fuzzy robust nonlinear controller for hydraulic rotary actuators in flight motion simulators is proposed. Compared with other three-order models of hydraulic rotary actuators, the proposed controller based on first-order nonlinear model is more easily applied in practice, whose control law is relatively simple. It not only does not need high-order derivative of desired command, but also does not require the feedback signals of velocity, acceleration and jerk of hydraulic rotary actuators. Another advantage is that it does not rely on any information of friction, inertia force and external disturbing force/torque, which are always difficult to resolve in flight motion simulators. Due to the special composite vane seals of rectangular cross-section and goalpost shape used in hydraulic rotary actuators, the leakage model is more complicated than that of traditional linear hydraulic cylinders. Adaptive multi-input single-output (MISO fuzzy compensators are introduced to estimate nonlinear uncertain functions about leakage and bulk modulus. Meanwhile, the decomposition of the uncertainties is used to reduce the total number of fuzzy rules. Different from other adaptive fuzzy compensators, a discontinuous projection mapping is employed to guarantee the estimation process to be bounded. Furthermore, with a sufficient number of fuzzy rules, the controller theoretically can guarantee asymptotic tracking performance in the presence of the above uncertainties, which is very important for high-accuracy tracking control of flight motion simulators. Comparative experimental results demonstrate the effectiveness of the proposed algorithm, which can guarantee transient performance and better final accurate tracking in the presence of uncertain nonlinearities and parametric uncertainties.

  2. Removal of PAHs from contaminated calyey soil by means of electro-osmosis

    NARCIS (Netherlands)

    Lima, A.T.; Kleingeld, P.J.; Heister, K.; Loch, J.P.G.

    2011-01-01

    The removal of polycyclic aromatic hydrocarbons (PAHs) from clayey soils is an intricate task. The low porosity of compacted clayey soil hinders bacterial activity and makes convective removal by hydraulic flow impossible. Electro-osmosis is a process that has been used for the mobilization and

  3. Electro-mechanical control of an on-chip optical beam splitter containing an embedded quantum emitter

    Science.gov (United States)

    Bishop, Z. K.; Foster, A. P.; Royall, B.; Bentham, C.; Clarke, E.; Skolnick, M. S.; Wilson, L. R.

    2018-05-01

    We demonstrate electro-mechanical control of an on-chip GaAs optical beam splitter containing a quantum dot single-photon source. The beam splitter consists of two nanobeam waveguides, which form a directional coupler (DC). The splitting ratio of the DC is controlled by varying the out-of-plane separation of the two waveguides using electro-mechanical actuation. We reversibly tune the beam splitter between an initial state, with emission into both output arms, and a final state with photons emitted into a single output arm. The device represents a compact and scalable tuning approach for use in III-V semiconductor integrated quantum optical circuits.

  4. Hydraulics and pneumatics

    CERN Document Server

    Parr, Andrew

    2006-01-01

    Nearly all industrial processes require objects to be moved, manipulated or subjected to some sort of force. This is frequently accomplished by means of electrical equipment (such as motors or solenoids), or via devices driven by air (pneumatics) or liquids (hydraulics).This book has been written by a process control engineer as a guide to the operation of hydraulic and pneumatic systems for all engineers and technicians who wish to have an insight into the components and operation of such a system.This second edition has been fully updated to include all recent developments su

  5. Positioning the laparoscopic camera with industrial robot arm

    DEFF Research Database (Denmark)

    Capolei, Marie Claire; Wu, Haiyan; Andersen, Nils Axel

    2017-01-01

    This paper introduces a solution for the movement control of the laparoscopic camera employing a teleoperated robotic assistant. The project propose an autonomous robotic solution based on an industrial manipulator, provided with a modular software which is applicable to large scale. The robot arm...... industrial robot arm is designated to accomplish this manipulation task. The software is implemented in ROS in order to facilitate future extensions. The experimental results shows a manipulator capable of moving fast and smoothly the surgical tool around a remote center of motion....

  6. Dual arm master controller for a bilateral servo-manipulator

    Science.gov (United States)

    Kuban, Daniel P.; Perkins, Gerald S.

    1989-01-01

    A master controller for a mechanically dissimilar bilateral slave servo-manipulator is disclosed. The master controller includes a plurality of drive trains comprising a plurality of sheave arrangements and cables for controlling upper and lower degrees of master movement. The cables and sheaves of the master controller are arranged to effect kinematic duplication of the slave servo-manipulator, despite mechanical differences therebetween. A method for kinematically matching a master controller to a slave servo-manipulator is also disclosed.

  7. Large remote manipulator operating and maintenance experience at IEM cell

    International Nuclear Information System (INIS)

    Hicks, D.F.; McGuinness, P.W.

    1985-01-01

    The Interim Examination and Maintenance (IEM) Cell at the Fast Flux Test Facility (FFTF) has two large Electro-Mechanical Manipulators (EMM's). These manipulators are used for cell operations (processing of reactor core components) as well as general cell maintenance. From our eleven years of operation and maintenance experience with these large EMM's, we have learned many lessons concerning manipulator design. This paper describes the IEM Cell EMM design features and discusses operating and maintenance experience at the IEM Cell

  8. Emulating a robotic manipulator arm with an hybrid motion-control system

    International Nuclear Information System (INIS)

    Aragón-González, G; León-Galicia, A; Noriega-Hernández, M; Salazar-Hueta, A

    2015-01-01

    A motion control system with four and 1/2 degrees of freedom, designed to move small objects within a 0.25 m3 space, parallel to a horizontal table, with high speed and performance similar to a robotic manipulator arm was built. The machine employs several actuators and control devices. Its main characteristic is to incorporate a servomotor, steeper motors, electromechanical and fluid power actuators and diverse control resources. A group of actuators arranged on a spherical coordinates system is attached to the servomotor platform. A linear pneumatic actuator with an angular grip provides the radial extension and load clamping capacity. Seven inductive proximity sensors and one encoder provide feedback, for operating the actuators under closed loop conditions. Communication between the sensors and control devices is organized by a PLC. A touch screen allows governing the system remotely, easily and interactively, without knowing the specific programming language of each control component. The graphic environment on the touch screen guides the user to design and store control programs, establishing coordinated automatic routines for moving objects in space, simulation and implementation of industrial positioning or machining processes

  9. Dual arm master controller for a bilateral servo-manipulator

    International Nuclear Information System (INIS)

    Kuban, D.P.; Perkins, G.S.

    1989-01-01

    A master controller for a mechanically dissimilar bilateral slave servo-manipulator is disclosed. The master controller includes a plurality of drive trains comprising a plurality of sheave arrangements and cables for controlling upper and lower degrees of master movement. The cables and sheaves of the master controller are arranged to effect kinematic duplication of the slave servo-manipulator, despite mechanical differences there between. A method for kinematically matching a master controller to a slave servo-manipulator is also disclosed. 13 figs

  10. Computer control of a multi-link manipulator

    International Nuclear Information System (INIS)

    Holt, J.E.; Thiruarooran, C.

    1988-01-01

    The Central Electricity Generating Board has a requirement for a manipulator which can deploy to its work location around obstacles. A multilink manipulator has been designed for this purpose. A computer control system designed to ease manipulator operation is described. Using the control program, the manipulator may be deployed using just 2 joysticks. Experience in the use of the program with an inspection manipulator at Sizewell 'A' Nuclear Power Station is discussed. When used to control a manipulator of 9 hydraulically actuated degrees of freedom, a control accuracy of about 1.5% of full extension has been achieved. (author)

  11. Robust Control of a Hydraulically Actuated Manipulator Using Sliding Mode Control

    DEFF Research Database (Denmark)

    Hansen, Michael Rygaard; Andersen, Torben Ole; Pedersen, Henrik Clemmensen

    2005-01-01

    This paper presents an approach to robust control called sliding mode control (SMC) applied to the a hydraulic servo system (HSS), consisting of a servo valve controlled symmetrical cylinder. The motivation for applying sliding mode control to hydraulically actuated systems is its robustness...

  12. Information booklet on personal protective equipment: arm and hand protection

    International Nuclear Information System (INIS)

    1992-01-01

    Fire, heat, cold, electro-magnetic and ionising radiation, electricity, chemicals, impacts, cuts, abrasion, etc. are the common hazards for arms and hands at work. The gloves chosen for protection of the arm and hand should cover those parts adequately and the material of the gloves should be capable of offering protection against the specific hazard involved. Criteria for choosing arm and hand protection equipment will be based on their shape and part of the arm and hand protected. Guide lines for choosing such personal protection equipment for nuclear facilities are given. (M.K.V.). 3 annexures, 1 appendix

  13. Evaluation of a New Backtrack Free Path Planning Algorithm for Manipulators

    Science.gov (United States)

    Islam, Md. Nazrul; Tamura, Shinsuke; Murata, Tomonari; Yanase, Tatsuro

    This paper evaluates a newly proposed backtrack free path planning algorithm (BFA) for manipulators. BFA is an exact algorithm, i.e. it is resolution complete. Different from existing resolution complete algorithms, its computation time and memory space are proportional to the number of arms. Therefore paths can be calculated within practical and predetermined time even for manipulators with many arms, and it becomes possible to plan complicated motions of multi-arm manipulators in fully automated environments. The performance of BFA is evaluated for 2-dimensional environments while changing the number of arms and obstacle placements. Its performance under locus and attitude constraints is also evaluated. Evaluation results show that the computation volume of the algorithm is almost the same as the theoretical one, i.e. it increases linearly with the number of arms even in complicated environments. Moreover BFA achieves the constant performance independent of environments.

  14. Hydraulic Actuators with Autonomous Hydraulic Supply for the Mainline Aircrafts

    Directory of Open Access Journals (Sweden)

    I. S. Shumilov

    2014-01-01

    Full Text Available Applied in the aircraft control systems, hydraulic servo actuators with autonomous hydraulic supply, so-called, hydraulic actuators of integrated configuration, i.e. combination of a source of hydraulic power and its load in the single unit, are aimed at increasing control system reliability both owing to elimination of the pipelines connecting the actuator to the hydraulic supply source, and owing to avoidance of influence of other loads failure on the actuator operability. Their purpose is also to raise control system survivability by eliminating the long pipeline communications and their replacing for the electro-conductive power supply system, thus reducing the vulnerability of systems. The main reason for a delayed application of the hydraulic actuators in the cutting-edge aircrafts was that such aircrafts require hydraulic actuators of considerably higher power with considerable heat releases, which caused an unacceptable overheat of the hydraulic actuators. Positive and negative sides of the hydraulic actuators, their alternative options of increased reliability and survivability, local hydraulic systems as an advanced alternative to independent hydraulic actuators are considered.Now to use hydraulic actuators in mainline aircrafts is inexpedient since there are the unfairly large number of the problems reducing, first and last, safety of flights, with no essential weight and operational advantages. Still works to create competitive hydraulic actuators ought to be continued.Application of local hydraulic systems (LHS will allow us to reduce length of pressure head and drain pipelines and mass of pipelines, as well as to raise their general fail-safety and survivability. Application of the LHS principle will allow us to use a majority of steering drive advantages. It is necessary to allocate especially the following:- ease of meeting requirements for the non-local spread of the engine weight;- essentially reducing length and weight of

  15. High precision detector robot arm system

    Science.gov (United States)

    Shu, Deming; Chu, Yong

    2017-01-31

    A method and high precision robot arm system are provided, for example, for X-ray nanodiffraction with an X-ray nanoprobe. The robot arm system includes duo-vertical-stages and a kinematic linkage system. A two-dimensional (2D) vertical plane ultra-precision robot arm supporting an X-ray detector provides positioning and manipulating of the X-ray detector. A vertical support for the 2D vertical plane robot arm includes spaced apart rails respectively engaging a first bearing structure and a second bearing structure carried by the 2D vertical plane robot arm.

  16. Light Duty Utility Arm computer software configuration management plan

    International Nuclear Information System (INIS)

    Philipp, B.L.

    1998-01-01

    This plan describes the configuration management for the Light Duty Utility Arm robotic manipulation arm control software. It identifies the requirement, associated documents, and the software control methodology. The Light Duty Utility Ann (LDUA) System is a multi-axis robotic manipulator arm and deployment vehicle, used to perform surveillance and characterization operations in support of remediation of defense nuclear wastes currently stored in the Hanford Underground Storage Tanks (USTs) through the available 30.5 cm (12 in.) risers. This plan describes the configuration management of the LDUA software

  17. Tolerance Towards Sensor Faults: An Application to a Flexible Arm Manipulator

    Directory of Open Access Journals (Sweden)

    Chee Pin Tan

    2006-12-01

    Full Text Available As more engineering operations become automatic, the need for robustness towards faults increases. Hence, a fault tolerant control (FTC scheme is a valuable asset. This paper presents a robust sensor fault FTC scheme implemented on a flexible arm manipulator, which has many applications in automation. Sensor faults affect the system's performance in the closed loop when the faulty sensor readings are used to generate the control input. In this paper, the non-faulty sensors are used to reconstruct the faults on the potentially faulty sensors. The reconstruction is subtracted from the faulty sensors to form a compensated ‘virtual sensor’ and this signal (instead of the normally used faulty sensor output is then used to generate the control input. A design method is also presented in which the FTC scheme is made insensitive to any system uncertainties. Two fault conditions are tested; total failure and incipient faults. Then the scheme robustness is tested by implementing the flexible joint's FTC scheme on a flexible link, which has different parameters. Excellent results have been obtained for both cases (joint and link; the FTC scheme caused the system performance is almost identical to the fault-free scenario, whilst providing an indication that a fault is present, even for simultaneous faults.

  18. Advanced Bimanual Manipulation Results from the DEXMART Project

    CERN Document Server

    2012-01-01

    Dexterous and autonomous manipulation is a key technology for the personal and service robots of the future. Advances in Bimanual Manipulation edited by Bruno Siciliano provides the robotics community with the most noticeable results of the four-year European project DEXMART (DEXterous and autonomous dual-arm hand robotic manipulation with sMART sensory-motor skills: A bridge from natural to artificial cognition). The volume covers a host of highly important topics in the field, concerned with modelling and learning of human manipulation skills, algorithms for task planning, human-robot interaction, and grasping, as well as hardware design of dexterous anthropomorphic hands. The results described in this five-chapter collection are believed to pave the way towards the development of robotic systems endowed with dexterous and human-aware dual-arm/hand manipulation skills for objects, operating with a high degree of autonomy in unstructured real-world environments.

  19. Hydraulic lift in a neotropical savanna: experimental manipulation and model simulations

    Science.gov (United States)

    Fabian G. Scholz; Sandra J. Bucci; William A. Hoffmann; Frederick C. Meinzer; Guillermo Goldstein

    2010-01-01

    The objective of this study was to assess the magnitude of hydraulic lift in Brazilian savannas (Cerrado) and to test the hypothesis that hydraulic lift by herbaceous plants contributes substantially to slowing the decline of water potential and water storage in the upper soil layers during the dry season. To this effect, field observations of soil water content and...

  20. Maestro: a tele-robotic system for decommissioning of nuclear plants

    International Nuclear Information System (INIS)

    Desbats, P.; Idasiak, J.M.

    2008-01-01

    Compared to electric manipulators, hydraulic manipulators can handle higher payloads with respect to their size and mass. However, due to their limited positioning resolution and dexterity, they are usually disqualified for precise tele-manipulation and high quality tele-operation. More over, experience feedback has shown that on-the-shelf hydraulic manipulators are not reliable when performing high demanding tasks in tele-operation for dismantling applications. In order to solve this problem, CEA (Commissariat l'Energie Atomique), in collaboration with Cybernetix company, has developed a computer-aided, high-precision remote handling system with force-feedback featuring the advanced hydraulic tele-robotic arm Maestro. (authors)

  1. stepping motor - hydraulic motor servo drives for an nc milling machine

    African Journals Online (AJOL)

    Dr Obe

    stepping motor Drive Assembly especially Designed for CNC systems". 13th Machine Tool Design and. Research. (MTDR) conference,. University of Birmingham, 1972. 2 Ertongur, N.A. "Investigation into the instability in an electro hydraulic control system for machine tools" Ph.D. Thesis, University of. Birmingham, UK. 1966 ...

  2. Optical logic gates based on electro-optic modulation with Sagnac interferometer.

    Science.gov (United States)

    Li, Qiliang; Zhu, Mengyun; Li, Dongqiang; Zhang, Zhen; Wei, Yizhen; Hu, Miao; Zhou, Xuefang; Tang, Xianghong

    2014-07-20

    In this work, we present a new structure to realize optical logic operation in a Sagnac interferometer with electro-optical modulation. In the scheme, we divide two counterpropagation signals in a Sagnac loop to two different arms with the electro-optical crystal by using two circulators. Lithium niobate materials whose electro-optical coefficient can be as large as 32.2×10(-12)  m/V make up the arms of the waveguides. Using the transfer matrix of the fiber coupler, we analyze the propagation of signals in this system and obtain the transmission characteristic curves and the extinction ratio. The results indicate that this optical switching has a high extinction ratio of about 60 dB and an ultrafast response time of 2.036 ns. In addition, the results reveal that the change of the dephasing between the two input signals and the modification of the modulation voltage added to the electro-optical crystal leads to the change of the extinction ratio. We also conclude that, in cases of the dephasing of two initial input signals Δφ=0, we can obtain the various logical operations, such as the logical operations D=A¯·B, D=A·B¯, C=A+B, and D=A⊕B in ports C and D of the system by adjusting the modulation voltage. When Δφ≠0, we obtain the arithmetic operations D=A+B, C=A⊕B, D=A·B¯, and C=A¯·B in ports C and D. This study is significant for the design of all optical networks by adjusting the modulation voltage.

  3. Geometric control of manipulators

    International Nuclear Information System (INIS)

    Thiruarooran, C.

    1996-01-01

    Resolved motion control enables the end effector to be moved as a rigid body in space without having to work out manually the joint combinations needed. Since a rigid body in space has three independent translational and three independent rotational movements, a manipulator with at least six joints can be controlled in this way. Normally the manipulator has more than six joints providing an infinite number of ways of moving the tip in the desired direction and this redundancy can be exploited in a variety of ways. Resolved motion tests performed on a hydraulically operated heavy duty manipulator at the Dungeness nuclear power plant are described. The results have shown that manipulators with as many as ten joints can be controlled under resolved tip motion and the areas which are critical to the performance of this type of control have been identified. (UK)

  4. Nonlinear Modeling and Coordinate Optimization of a Semi-Active Energy Regenerative Suspension with an Electro-Hydraulic Actuator

    Directory of Open Access Journals (Sweden)

    Farong Kou

    2018-01-01

    Full Text Available In order to coordinate the damping performance and energy regenerative performance of energy regenerative suspension, this paper proposes a structure of a vehicle semi-active energy regenerative suspension with an electro-hydraulic actuator (EHA. In light of the proposed concept, a specific energy regenerative scheme is designed and a mechanical properties test is carried out. Based on the test results, the parameter identification for the system model is conducted using a recursive least squares algorithm. On the basis of the system principle, the nonlinear model of the semi-active energy regenerative suspension with an EHA is built. Meanwhile, linear-quadratic-Gaussian control strategy of the system is designed. Then, the influence of the main parameters of the EHA on the damping performance and energy regenerative performance of the suspension is analyzed. Finally, the main parameters of the EHA are optimized via the genetic algorithm. The test results show that when a sinusoidal is input at the frequency of 2 Hz and the amplitude of 30 mm, the spring mass acceleration root meam square value of the optimized EHA semi-active energy regenerative suspension is reduced by 22.23% and the energy regenerative power RMS value is increased by 40.51%, which means that while meeting the requirements of vehicle ride comfort and driving safety, the energy regenerative performance is improved significantly.

  5. Development master arm of 2-DOF planar parallel manipulator for In-Vitro Fertilization

    Science.gov (United States)

    Thamrongaphichartkul, Kitti; Vongbunyong, Supachai; Nuntakarn, Lalana

    2018-01-01

    Micromanipulator is a mechanical device used for manipulating miniature objects in the order of micron. It is widely used in In-Vitro Fertilization (IVF) in which sperms will be held in a micro-needle and penetrate to an oocyte for fertilization. IVF needs to be performed by high skill embryologists to control the movement of the needle accurately due to the lack of tactile perception of the user. Haptic device is a device that can transmit and simulate position, velocity and force in order to enhance interaction between the user and system. However, commercially available haptic devices have unnecessary degrees of freedom and limited workspace which are inappropriate for IVF process. This paper focuses on development of a haptic device for using in IVF process. It will be used as a master arm for the master-slave system for IVF process in order to enhance the ability of users to control the micromanipulator. As a result, the embryologist is able to carry out the IVF process more effectively with having tactile perception.

  6. CHAMP: A bespoke integrated system for mobile manipulation

    CSIR Research Space (South Africa)

    Van Eden, B

    2014-11-01

    Full Text Available for Mobile Manipulation Beatrice van Eden, Benjamin Rosman, Daniel Withey, Terence Ratshidaho, Mogomotsi Keaikitse, Ditebogo Masha, Ashley Kleinhans, and Ahmed Shaik Mobile Intelligent Autonomous Systems Modelling and Digital Science Council for Scientific... as a rear caster. Each arm has 7 DoF, with an attached Barrett hand. UMAN [19], the UMass Mobile MANipulator also uses a 7 DoF Barrett WAM, with a three-fingered Barrett hand. The arm is mounted on modified Nomadic XR4000 mobile base having four caster...

  7. Simulation of cooperating robot manipulators on a mobile platform

    Science.gov (United States)

    Murphy, Steve H.; Wen, John T.; Saridis, George N.

    1990-01-01

    The dynamic equations of motion for two manipulators holding a common object on a freely moving mobile platform are developed. The full dynamic interactions from arms to platform and arm-tip to arm-tip are included in the formulation. The development of the closed chain dynamics allows for the use of any solution for the open topological tree of base and manipulator links. In particular, because the system has 18 degrees of freedom, recursive solutions for the dynamic simulation become more promising for efficient calculations of the motion. Simulation of the system is accomplished through a MATLAB program, and the response is visualized graphically using the SILMA Cimstation.

  8. 3D Laser Scanner for Underwater Manipulation.

    Science.gov (United States)

    Palomer, Albert; Ridao, Pere; Youakim, Dina; Ribas, David; Forest, Josep; Petillot, Yvan

    2018-04-04

    Nowadays, research in autonomous underwater manipulation has demonstrated simple applications like picking an object from the sea floor, turning a valve or plugging and unplugging a connector. These are fairly simple tasks compared with those already demonstrated by the mobile robotics community, which include, among others, safe arm motion within areas populated with a priori unknown obstacles or the recognition and location of objects based on their 3D model to grasp them. Kinect-like 3D sensors have contributed significantly to the advance of mobile manipulation providing 3D sensing capabilities in real-time at low cost. Unfortunately, the underwater robotics community is lacking a 3D sensor with similar capabilities to provide rich 3D information of the work space. In this paper, we present a new underwater 3D laser scanner and demonstrate its capabilities for underwater manipulation. In order to use this sensor in conjunction with manipulators, a calibration method to find the relative position between the manipulator and the 3D laser scanner is presented. Then, two different advanced underwater manipulation tasks beyond the state of the art are demonstrated using two different manipulation systems. First, an eight Degrees of Freedom (DoF) fixed-base manipulator system is used to demonstrate arm motion within a work space populated with a priori unknown fixed obstacles. Next, an eight DoF free floating Underwater Vehicle-Manipulator System (UVMS) is used to autonomously grasp an object from the bottom of a water tank.

  9. Computational simulator of robotic manipulators

    International Nuclear Information System (INIS)

    Leal, Alexandre S.; Campos, Tarcisio P.R.

    1995-01-01

    Robotic application for industrial plants is discussed and a computational model for a mechanical manipulator of three links is presented. A neural network feed-forward type has been used to model the dynamic control of the manipulator. A graphic interface was developed in C programming language as a virtual world in order to visualize and simulate the arm movements handling radioactive waste environment. (author). 7 refs, 5 figs

  10. Electro-chemo-hydro-mechanical coupling in clayey media; Couplage electro-chimio-hydro-mecaniques dans les milieux argileux

    Energy Technology Data Exchange (ETDEWEB)

    Lemaire, Th

    2004-12-15

    The aim of this study is to understand coupled phenomena that occur in swelling porous materials like clays. Electro-chemo-hydro-mechanical contributions are taken into account to analyze transfers in such minerals. In a first part, a general discussion is proposed to introduce mineralogical and physico- chemical considerations of clayey media. An important objective of this chapter is to show the crucial role of the microstructure. In a second part is presented an imbibition test in a MX80 bentonite powder. The hydraulic diffusivity versus water content curve's decrease is explained thanks to a double porosity model that shows the progressive collapse of meso-pores due to swelling effects at the micro-scale. Thus a multi-scale analysis is necessary to well describe clayey media behaviour. The third chapter exposes such a multi-scale modelling (periodic homogenization). It is based on the double-layer theory and introduces an innovative concept of virtual electrolyte solution. First numerical results are given in a simple geometry (parallel platelets). In the next part are proposed numerical simulations of two kinds: response of the system to a chemical gradient and simulation of electro-osmosis. The end of this chapter puts into relief the necessity to integrate pH effects in the model. In the last part, chemical surface exchanges are incorporated in the modelling to understand pH and ionic force roles in electro-osmotic process. (author)

  11. Octopus-inspired multi-arm robotic swimming.

    Science.gov (United States)

    Sfakiotakis, M; Kazakidi, A; Tsakiris, D P

    2015-05-13

    The outstanding locomotor and manipulation characteristics of the octopus have recently inspired the development, by our group, of multi-functional robotic swimmers, featuring both manipulation and locomotion capabilities, which could be of significant engineering interest in underwater applications. During its little-studied arm-swimming behavior, as opposed to the better known jetting via the siphon, the animal appears to generate considerable propulsive thrust and rapid acceleration, predominantly employing movements of its arms. In this work, we capture the fundamental characteristics of the corresponding complex pattern of arm motion by a sculling profile, involving a fast power stroke and a slow recovery stroke. We investigate the propulsive capabilities of a multi-arm robotic system under various swimming gaits, namely patterns of arm coordination, which achieve the generation of forward, as well as backward, propulsion and turning. A lumped-element model of the robotic swimmer, which considers arm compliance and the interaction with the aquatic environment, was used to study the characteristics of these gaits, the effect of various kinematic parameters on propulsion, and the generation of complex trajectories. This investigation focuses on relatively high-stiffness arms. Experiments employing a compliant-body robotic prototype swimmer with eight compliant arms, all made of polyurethane, inside a water tank, successfully demonstrated this novel mode of underwater propulsion. Speeds of up to 0.26 body lengths per second (approximately 100 mm s(-1)), and propulsive forces of up to 3.5 N were achieved, with a non-dimensional cost of transport of 1.42 with all eight arms and of 0.9 with only two active arms. The experiments confirmed the computational results and verified the multi-arm maneuverability and simultaneous object grasping capability of such systems.

  12. Operating gains achieved by a new generation of remotely controlled manipulators

    International Nuclear Information System (INIS)

    Djedidi, A.; Selliez-Vandernotte, C.; Malcolm, F.

    2014-01-01

    A high performance remotely controlled mechanical master slave arm with direct transmission via cable and transmission rods has been converted to a new generation manipulator with electrical master slave arm and motion module with integrated software. The redesigned powered manipulator with software control improves efficiency and ergonomics while increasing operating field space. The mechanical master arm has been replaced by an electrical robotic master arm using haptic technology. The movements initiated by the operator are transmitted in real time to the slave arm via the servo-motors inside the motion module. The mechanical link between master and slave is eliminated and some mechanical constraints have been replaced by software applications. The operator benefits from an improved working position and vibration filtering plus full range high performance force feedback with reduced effort requirement. (authors)

  13. Electro-Thermal-Mechanical Simulation Capability Final Report

    International Nuclear Information System (INIS)

    White, D

    2008-01-01

    This is the Final Report for LDRD 04-ERD-086, 'Electro-Thermal-Mechanical Simulation Capability'. The accomplishments are well documented in five peer-reviewed publications and six conference presentations and hence will not be detailed here. The purpose of this LDRD was to research and develop numerical algorithms for three-dimensional (3D) Electro-Thermal-Mechanical simulations. LLNL has long been a world leader in the area of computational mechanics, and recently several mechanics codes have become 'multiphysics' codes with the addition of fluid dynamics, heat transfer, and chemistry. However, these multiphysics codes do not incorporate the electromagnetics that is required for a coupled Electro-Thermal-Mechanical (ETM) simulation. There are numerous applications for an ETM simulation capability, such as explosively-driven magnetic flux compressors, electromagnetic launchers, inductive heating and mixing of metals, and MEMS. A robust ETM simulation capability will enable LLNL physicists and engineers to better support current DOE programs, and will prepare LLNL for some very exciting long-term DoD opportunities. We define a coupled Electro-Thermal-Mechanical (ETM) simulation as a simulation that solves, in a self-consistent manner, the equations of electromagnetics (primarily statics and diffusion), heat transfer (primarily conduction), and non-linear mechanics (elastic-plastic deformation, and contact with friction). There is no existing parallel 3D code for simulating ETM systems at LLNL or elsewhere. While there are numerous magnetohydrodynamic codes, these codes are designed for astrophysics, magnetic fusion energy, laser-plasma interaction, etc. and do not attempt to accurately model electromagnetically driven solid mechanics. This project responds to the Engineering R and D Focus Areas of Simulation and Energy Manipulation, and addresses the specific problem of Electro-Thermal-Mechanical simulation for design and analysis of energy manipulation systems

  14. Modeling and control of a hydraulically actuated flexible-prismatic link robot

    International Nuclear Information System (INIS)

    Love, L.; Kress, R.; Jansen, J.

    1996-12-01

    Most of the research related to flexible link manipulators to date has focused on single link, fixed length, single plane of vibration test beds. In addition, actuation has been predominantly based upon electromagnetic motors. Ironically, these elements are rarely found in the existing industrial long reach systems. This manuscript describes a new hydraulically actuated, long reach manipulator with a flexible prismatic link at Oak Ridge National Laboratory (ORNL). Focus is directed towards both modeling and control of hydraulic actuators as well as flexible links that have variable natural frequencies

  15. 3D Laser Scanner for Underwater Manipulation

    Directory of Open Access Journals (Sweden)

    Albert Palomer

    2018-04-01

    Full Text Available Nowadays, research in autonomous underwater manipulation has demonstrated simple applications like picking an object from the sea floor, turning a valve or plugging and unplugging a connector. These are fairly simple tasks compared with those already demonstrated by the mobile robotics community, which include, among others, safe arm motion within areas populated with a priori unknown obstacles or the recognition and location of objects based on their 3D model to grasp them. Kinect-like 3D sensors have contributed significantly to the advance of mobile manipulation providing 3D sensing capabilities in real-time at low cost. Unfortunately, the underwater robotics community is lacking a 3D sensor with similar capabilities to provide rich 3D information of the work space. In this paper, we present a new underwater 3D laser scanner and demonstrate its capabilities for underwater manipulation. In order to use this sensor in conjunction with manipulators, a calibration method to find the relative position between the manipulator and the 3D laser scanner is presented. Then, two different advanced underwater manipulation tasks beyond the state of the art are demonstrated using two different manipulation systems. First, an eight Degrees of Freedom (DoF fixed-base manipulator system is used to demonstrate arm motion within a work space populated with a priori unknown fixed obstacles. Next, an eight DoF free floating Underwater Vehicle-Manipulator System (UVMS is used to autonomously grasp an object from the bottom of a water tank.

  16. Flexible kinesthetic distance perception: when do your arms tell you how far you have walked?

    Science.gov (United States)

    Harrison, Steven J; Kuznetsov, Nikita; Breheim, Samuel

    2013-01-01

    Given the flexible organization of locomotion evidenced in the many ways the limbs can be coordinated, the authors explored the potentially correspondingly flexible organization of nonvisual (kinesthetic) distance perception. As kinesthetic distance perception is known to be affected by how the limbs are coordinated, the authors probed the potential perceptual contribution of the arms during locomotion by manipulating arm-leg coordination patterns in blind-walked distance-matching tasks. Whereas manipulation of arm-leg coordination for walking with free-swinging arms had no observable perceptual consequences, comparable manipulation for walking with hiking poles did affect distance matching. These results suggest that under conditions in which the arms act to propel the body (e.g., crawling or stair-climbing) a person's nonvisual sense of movement is conveyed in the coordinated actions of all four limbs.

  17. Practical application with plc in manipulation of a robotic arm

    Directory of Open Access Journals (Sweden)

    Cristian Barz

    2014-12-01

    Full Text Available This paper presents the use of a robotic arm PLC Siemens in order not using CNC commands. This is done by programming the PLC ladder diagram language that makes movement on the three axes of the arm by means of stepper motors. Required command console PLC is built with the help of a touch screen HMI Weintek. In the user interface are introduced distances and displacement speeds on the three axes.

  18. Experimental evaluation of control strategies for hydraulic servo robot

    DEFF Research Database (Denmark)

    Bech, Michael Møller; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    In this paper different linear and non-linear controllers applied to a hydraulically driven servo robot are evaluated and validated. The task is to make the actuators of the manipulator track a position reference with minimum error. Hydraulic systems are intrinsically non-linear and using linear...... in industrial servo drives. The different controllers are compared and evaluated from simulation and experimental results....

  19. Transmission Characteristics on Wire-Driven Links of a Bridge Transported Servo Manipulator for the ACP Equipment Maintenance

    International Nuclear Information System (INIS)

    Park, Byung Suk; Jin, Jae Hyun; Song, Tae Gil; Kim, Sung Hyun; Yoon, Ji Sup

    2004-01-01

    A bridge transported servo manipulator (BTSM) system for the advanced spent fuel conditioning process (ACP) has been developed to overcome the limitation of access, which is a drawback of mechanical master-slave manipulators (MSM) for the equipment maintenance. The servo manipulator is composed of a slave manipulator attached to the telescoping tube sets equipped with the overhead bridge installed at a hot cell and a master manipulator installed at an out-of-hot cell. Each manipulator has 7 degrees-of-freedom (DOF): a body rotation, an upper-arm tilt, a lower-arm tilt, a lower-arm rotation, a wrist pan and tilt, and a grasp motion. A wire-driven mechanism for a lower-arm rotation, a wrist pan and tilt, and a grasp motion of the manipulator has been adopted to increase the handling capacity compared to the manipulator weight and decrease the friction. The main disadvantage of the wire-driven mechanism is that if one link is in motion, other links can be affected. In this paper, the transmission characteristics among the wire-driven links have been formulated to overcome this drawback. The unexpected behaviors are confirmed by analyses of transmission characteristics as well as experiments. Also, the experimental results show that the unexpected behaviors are greatly decreased by the proposed compensation equations

  20. Development of a super-redundant multijoint manipulator for maintenance of nuclear reactors

    International Nuclear Information System (INIS)

    Ma, Shugen; Hirose, Shigeo.

    1994-01-01

    A tendon-driven manipulator, the CT Arm, has a specific tendon traction transmission mechanism, in which a pair of tendons for driving a joint is pulled from base actuators via pulleys mounted on the based-side joints. The mechanism makes the most of the coupled drive function of the tendon tractions and thus enables the lightweight manipulator to exhibit enormous payload capability. By this tendon-driven mechanism, a multijoint manipulator with super-redundant degrees of freedom could be realized, which is suitable to the maintenance of nuclear reactors. In this article, we introduce the CT Arm and discuss the possibility to generate a multijoint maintenance manipulator which has a super-redundant degrees of freedom. (author)

  1. A humane protocol for electro-stunning and killing of Nile tilapia in fresh water

    NARCIS (Netherlands)

    Lambooij, E.; Gerritzen, M.A.; Reimert, H.G.M.; Burggraaf, D.; Vis, van de J.W.

    2008-01-01

    Behavioural, neural and physiological parameters were scored after electro-stunning of Nile tilapia (Oreochromis niloticus) in three positions to an electric field in fresh water. An overall current density, 1.0 Arms/dm2, 50 Hz sinusoidal, applied for 1 s top-to-bottom in water (700 ¿S/cm), induced

  2. Grasp planning for a reconfigurable parallel robot with an underactuated arm structure

    Directory of Open Access Journals (Sweden)

    M. Riedel

    2010-12-01

    Full Text Available In this paper, a novel approach of grasp planning is applied to find out the appropriate grasp points for a reconfigurable parallel robot called PARAGRIP (Parallel Gripping. This new handling system is able to manipulate objects in the six-dimensional Cartesian space by several robotic arms using only six actuated joints. After grasping, the contact elements at the end of the underactuated arm mechanisms are connected to the object which forms a closed loop mechanism similar to the architecture of parallel manipulators. As the mounting and grasp points of the arms can easily be changed, the manipulator can be reconfigured to match the user's preferences and needs. This paper raises the question, how and where these grasp points are to be placed on the object to perform well for a certain manipulation task.

    This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010, 19 August 2010, Montréal, Canada.

  3. Adaptive Sliding Mode Control for Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    This paper presents a new adaptive sliding mode controller generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD’s). The proposed control scheme requires limited knowledge on system parameters, and employs only piston- and valve spool position feedback...... employing parameter adaption through a recursive algorithm is presented. This is based on a reduced order model approximation of a VCD with unmatched valve flow- and cylinder asymmetries. Bounds on parameters are obtained despite lack of parameter knowledge, and the proposed controller demonstrates improved...

  4. Euler-Lagrange modeling for a seven degree of freedom Manipulator

    NARCIS (Netherlands)

    Muñoz Arias, Mauricio; Scherpen, Jacquelien M.A.

    2011-01-01

    The Philips experimental robot arm is a kinematically redundant manipulator which is mainly aimed at increasing dexterity. The robot manipulator, developed by Philips Applied Technologies for domotic applications, has seven degrees of freedom and includes humanoid characteristics of a upper limb

  5. W-026, acceptance test report manipulator system

    International Nuclear Information System (INIS)

    Watson, T.L.

    1997-01-01

    The purpose of the WRAP Manipulator System Acceptance Test Plan (ATP) is to verify that the 4 glovebox sets of WRAP manipulator components, including rail/carriage, slave arm, master controller and auxiliary equipment, meets the requirements of the functional segments of 14590 specification. The demonstration of performance elements of the ATP are performed as a part of the Assembly specifications. Manipulator integration is integrated in the performance testing of the gloveboxes. Each requirement of the Assembly specification will be carried out in conjunction with glovebox performance tests

  6. Robust sampled-data control of hydraulic flight control actuators

    OpenAIRE

    Kliffken, Markus Gustav

    1997-01-01

    In todays flight-by-wire systems the primary flight control surfaces of modern commercial and transport aircraft are driven by electro hydraulic linear actuators. Changing flight conditions as well as nonlinear actuator dynamics may be interpreted as parameter uncertainties of the linear actuator model. This demands a robust design for the controller. Here the parameter space design is used for the direct sampled-data controller synthesis. Therefore, a static output controller is choosen, the...

  7. Counterweight system for master-slave manipulator

    International Nuclear Information System (INIS)

    Haaker, L.W.; Jelatis, D.G.

    1981-01-01

    A counterweight system is described for use in a remote control master-slave manipulator. The manipulator consists of a rotatable horizontal support adapted to extend through the wall and two longitudinally extensible arms, a master and a slave, pivotally connected one to each end of the support. Within the support there is a means of translating linear motion to rotary motion for transfer through the barrier wall and retranslating to linear motion. (U.K.)

  8. Fault Diagnosis of Hydraulic Servo Valve Based on Genetic Optimization RBF-BP Neural Network

    Directory of Open Access Journals (Sweden)

    Li-Ping FAN

    2014-04-01

    Full Text Available Electro-hydraulic servo valves are core components of the hydraulic servo system of rolling mills. It is necessary to adopt an effective fault diagnosis method to keep the hydraulic servo valve in a good work state. In this paper, RBF and BP neural network are integrated effectively to build a double hidden layers RBF-BP neural network for fault diagnosis. In the process of training the neural network, genetic algorithm (GA is used to initialize and optimize the connection weights and thresholds of the network. Several typical fault states are detected by the constructed GA-optimized fault diagnosis scheme. Simulation results shown that the proposed fault diagnosis scheme can give satisfactory effect.

  9. Development of re-locatable head frame system using hydraulic arms for fractionated stereotactic radiotherapy and CT evaluation of repositioning accuracy

    International Nuclear Information System (INIS)

    Kitamura, Masayuki; Kunieda, Etsuo; Kawaguchi, Osamu; Ando, Yutaka; Shigematsu, Naoyuki; Shiba, Toshiyuki; Kubo, Atsushi

    2002-01-01

    The purpose of this study was to develop a novel re-locatable head frame system consisting of a dental cast and hydraulic arms as an immobilization device for fractionated stereotactic radiotherapy and to evaluate the repositioning accuracy by measurement of landmark coordinates in repeated computed tomography (CT) examinations. The acrylic dental casts were customized for each patient. First the dental cast was attached to the upper jaw of the patient, then the dental cast was connected to a Leksell stereotactic frame, which was finally secured by two hydraulic arms. Since this system is compatible with the Leksell frame, stereotactic indicators could be used to obtain coordinates of anatomical landmarks of the head. Seven patients treated by fractionated stereotactic radiotherapy underwent repeated quality-assurance CTs during their treatment courses. We evaluated the coordinates of the short process of incus and the top of crista galli as reference points for evaluation of variation in a total of 26 repeat CT data sets, and then x, y, and z fluctuations relative to their positions in the treatment-planning CTs. The distances among the reference points of both processes of incus and the top of crista galli were calculated to evaluate the feasibility of the method. The distances were less than 0.5 mm on averages and less than 1 mm in the standard deviations. The respective fluctuations in the x, y and z directions were less than 1 mm in mean values and less than 2 mm in standard deviations. The fluctuations in distance were less than 2 mm on average and in standard deviations. The fluctuation of the center of three reference points was 0.7 mm on average and the rotation of the cranium was 1.0 degree in average. We concluded that our evaluation method is feasible and the reproducibility of the fixation system is acceptable for its routine use in stereotactic radiotherapy. (author)

  10. Electro-chemo-hydro-mechanical coupling in clayey media

    International Nuclear Information System (INIS)

    Lemaire, Th.

    2004-12-01

    The aim of this study is to understand coupled phenomena that occur in swelling porous materials like clays. Electro-chemo-hydro-mechanical contributions are taken into account to analyze transfers in such minerals. In a first part, a general discussion is proposed to introduce mineralogical and physico- chemical considerations of clayey media. An important objective of this chapter is to show the crucial role of the microstructure. In a second part is presented an imbibition test in a MX80 bentonite powder. The hydraulic diffusivity versus water content curve's decrease is explained thanks to a double porosity model that shows the progressive collapse of meso-pores due to swelling effects at the micro-scale. Thus a multi-scale analysis is necessary to well describe clayey media behaviour. The third chapter exposes such a multi-scale modelling (periodic homogenization). It is based on the double-layer theory and introduces an innovative concept of virtual electrolyte solution. First numerical results are given in a simple geometry (parallel platelets). In the next part are proposed numerical simulations of two kinds: response of the system to a chemical gradient and simulation of electro-osmosis. The end of this chapter puts into relief the necessity to integrate pH effects in the model. In the last part, chemical surface exchanges are incorporated in the modelling to understand pH and ionic force roles in electro-osmotic process. (author)

  11. MODULAR MANIPULATOR FOR ROBOTICS APPLICATIONS

    International Nuclear Information System (INIS)

    Geisinger, Joseph W. Ph.D.

    2001-01-01

    ARM Automation, Inc. is developing a FR-amework of modular actuators that can address the DOE's wide range of robotics needs. The objective of this effort is to demonstrate the effectiveness of this technology by constructing a manipulator FR-om these actuators within a glovebox for Automated Plutonium Processing (APP). At the end of the project, the system of actuators was used to construct several different manipulator configurations, which accommodate common glovebox tasks such as repackaging. The modular nature and quickconnects of this system simplify installation into ''hot'' boxes and any potential modifications or repair therein. This work focused on the development of self-contained robotic actuator modules including the embedded electronic controls for the purpose of building a manipulator system. Both of the actuators developed under this project contain the control electronics, sensors, motor, gear train, wiring, system communications and mechanical interfaces of a complete robotics servo device. Test actuators and accompanying DISC(trademark)s underwent validation testing at The University of Texas at Austin and ARM Automation, Inc. following final design and fabrication. The system also included custom links, an umbilical cord, an open architecture PC-based system controller, and operational software that permitted integration into a completely functional robotic manipulator system. The open architecture on which this system is based avoids proprietary interfaces and communication protocols which only serve to limit the capabilities and flexibility of automation equipment. The system was integrated and tested in the contractor's facility for intended performance and operations. The manipulator was tested using the full-scale equipment and process mock-ups. The project produced a practical and operational system including a quantitative evaluation of its performance and cost

  12. On Application of Second Order Sliding Mode Control to Electro-Hydraulic Systems

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2014-01-01

    This paper discusses the application of second order mode controls to hydraulic valve-cylinder drives with a special focus on the limitations resulting from nonlinear dynamic effects in flow control valves. Second order sliding mode algorithms appear highly attractive in the successive...

  13. Optimization of Liquid DiElectroPhoresis (LDEP Digital Microfluidic Transduction for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Hiroyuki Fujita

    2011-06-01

    Full Text Available Digital microfluidic has recently been under intensive study, as an effective method to carry out liquid manipulation in Lab-On-a-Chip (LOC systems. Among droplet actuation forces, ElectroWetting on Dielectric (EWOD and Liquid DiElectroPhoresis (LDEP are powerful tools, used in many LOC platforms. Such digital microfluidic transductions do not require integration of complex mechanical components such as pumps and valves to perform the fluidic operations. However, although LDEP has been proved to be efficient to carry and manipulate biological components in insulating liquids, this microfluidic transduction requires several hundreds of volts at relatively high frequencies (kHz to MHz. With the purpose to develop integrated microsystems µ-TAS (Micro Total Analysis System or Point of Care systems, the goal here is to reduce such high actuation voltage, the power consumption, though using standard dielectric materials. This paper gives key rules to determine the best tradeoff between liquid manipulation efficiency, low-power consumption and robustness of microsystems using LDEP actuation. This study leans on an electromechanical model to describe liquid manipulation that is applied to an experimental setup, and provides precise quantification of both actuation voltage Vth and frequency fc thresholds between EWOD and LDEP regimes. In particular, several parameters will be investigated to quantify Vth and fc, such as the influence of the chip materials, the electrodes size and the device configurations. Compared to current studies in the field, significant reduction of both Vth and fc is achieved by optimization of the aforementioned parameters.

  14. Controllable chaos in hybrid electro-optomechanical systems

    Science.gov (United States)

    Wang, Mei; Lü, Xin-You; Ma, Jin-Yong; Xiong, Hao; Si, Liu-Gang; Wu, Ying

    2016-01-01

    We investigate the nonlinear dynamics of a hybrid electro-optomechanical system (EOMS) that allows us to realize the controllable opto-mechanical nonlinearity by driving the microwave LC resonator with a tunable electric field. A controllable optical chaos is realized even without changing the optical pumping. The threshold and lifetime of the chaos could be optimized by adjusting the strength, frequency, or phase of the electric field. This study provides a method of manipulating optical chaos with an electric field. It may offer the prospect of exploring the controllable chaos in on-chip optoelectronic devices and its applications in secret communication. PMID:26948505

  15. Controllable chaos in hybrid electro-optomechanical systems.

    Science.gov (United States)

    Wang, Mei; Lü, Xin-You; Ma, Jin-Yong; Xiong, Hao; Si, Liu-Gang; Wu, Ying

    2016-03-07

    We investigate the nonlinear dynamics of a hybrid electro-optomechanical system (EOMS) that allows us to realize the controllable opto-mechanical nonlinearity by driving the microwave LC resonator with a tunable electric field. A controllable optical chaos is realized even without changing the optical pumping. The threshold and lifetime of the chaos could be optimized by adjusting the strength, frequency, or phase of the electric field. This study provides a method of manipulating optical chaos with an electric field. It may offer the prospect of exploring the controllable chaos in on-chip optoelectronic devices and its applications in secret communication.

  16. Evaluation of Linear and Non-Linear Control Schemes Applied to a Hydraulic Servo System

    DEFF Research Database (Denmark)

    Andersen, Torben Ole; Hansen, Michael Rygaard; Pedersen, Henrik Clemmensen

    2005-01-01

    Due to the innovation of low-cost electronics such as sensors, microcontrollers etc., the focus on highperformance motion control is increasing. This work focuses on position control of single-input single-output hydraulic servo-systems in general. A hydraulically actuated robotic manipulator...

  17. Removal of PAHs from contaminated clayey soil by means of electro-osmosis

    KAUST Repository

    Lima, Ana T.

    2011-06-01

    The removal of polycyclic aromatic hydrocarbons (PAHs) from clayey soils is an intricate task. The low porosity of compacted clayey soil hinders bacterial activity and makes convective removal by hydraulic flow impossible. Electro-osmosis is a process that has been used for the mobilization and cleanup of contaminants in clayey soils with varying successes. The present study focuses on the remediation of a contaminated peaty clay soil, located in Olst - the Netherlands, by means of electro-osmosis. The soil was originally contaminated by an asphalt production plant, active from 1903 to 1983, and presents high levels of all 16 priority PAHs indicated by the US Environmental Protection Agency (EPA). Such a long contact times of PAH with the soil (≥100 years) presents a unique study material with well established solid/liquid contaminant partitioning equilibrium, preferable to artificially spiked soil. A batch of 6 electro-osmosis laboratory experiments was carried out to study the removal of 16 PAHs through electro-osmosis. In these experiments, water and a surfactant (Tween 80) were used to enhance the PAH desorption. The electro-osmotic conductivities ranged from 2.88 × 10-10 to a substantial 1.19 × 10-7 m2 V-1 s -1 when applying a current density of 0.005-0.127 A m-2. Electro-osmosis was expected to occur towards the cathode, because of natural soil characteristics (negative zeta potential), but presented scattered directions. The use of reference electrodes proved to be very effective to the prediction of the flow direction. Finally, the addition of Tween 80 as a surfactant enhanced PAH removal up to 30% of the total PAH content of the soil in 9 days. © 2011 Elsevier B.V.

  18. Kinesthetic coupling between operator and remote manipulator

    Science.gov (United States)

    Bejczy, A. K.; Salisbury, J. K., Jr.

    1980-01-01

    A universal force-reflecting hand controller has been developed which allows the establishment of a kinesthetic coupling between the operator and a remote manipulator. The six-degree-of-freedom controller was designed to generate forces and torques on its three positional and three rotational axes in order to permit the operator to accurately feel the forces encountered by the manipulator and be as transparent to operate as possible. The universal controller has been used in an application involving a six-degree-of-freedom mechanical arm equipped with a six-dimensional force-torque sensor at its base. In this application, the hand controller acts as a position control input device to the arm, while forces and torques sensed at the base of the mechanical hand back drive the hand controller. The positional control relation and the back driving of the controller according to inputs experienced by the force-torque sensor are established through complex mathematical transformations performed by a minicomputer. The hand controller is intended as a development tool for investigating force-reflecting master-slave manipulator control technology.

  19. Kinematics/statics analysis of a novel serial-parallel robotic arm with hand

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yi; Dai, Zhuohong; Ye, Nijia; Wang, Peng [Yanshan University, Hebei (China)

    2015-10-15

    A robotic arm with fingered hand generally has multi-functions to complete various complicated operations. A novel serial-parallel robotic arm with a hand is proposed and its kinematics and statics are studied systematically. A 3D prototype of the serial-parallel robotic arm with a hand is constructed and analyzed by simulation. The serial-parallel robotic arm with a hand is composed of an upper 3RPS parallel manipulator, a lower 3SPR parallel manipulator and a hand with three finger mechanisms. Its kinematics formulae for solving the displacement, velocity, acceleration of are derived. Its statics formula for solving the active/constrained forces is derived. Its reachable workspace and orientation workspace are constructed and analyzed. Finally, an analytic example is given for solving the kinematics and statics of the serial-parallel robotic arm with a hand and the analytic solutions are verified by a simulation mechanism.

  20. Kinematics/statics analysis of a novel serial-parallel robotic arm with hand

    International Nuclear Information System (INIS)

    Lu, Yi; Dai, Zhuohong; Ye, Nijia; Wang, Peng

    2015-01-01

    A robotic arm with fingered hand generally has multi-functions to complete various complicated operations. A novel serial-parallel robotic arm with a hand is proposed and its kinematics and statics are studied systematically. A 3D prototype of the serial-parallel robotic arm with a hand is constructed and analyzed by simulation. The serial-parallel robotic arm with a hand is composed of an upper 3RPS parallel manipulator, a lower 3SPR parallel manipulator and a hand with three finger mechanisms. Its kinematics formulae for solving the displacement, velocity, acceleration of are derived. Its statics formula for solving the active/constrained forces is derived. Its reachable workspace and orientation workspace are constructed and analyzed. Finally, an analytic example is given for solving the kinematics and statics of the serial-parallel robotic arm with a hand and the analytic solutions are verified by a simulation mechanism.

  1. Graphics and control of the guide tube assembly reinforcement manipulators at Sizewell 'A'

    International Nuclear Information System (INIS)

    Burden, C.

    1996-01-01

    A method was devised to reinforce the lower lug welds of the Guide Tube Assemblies (GTA's) at Sizewell 'A'. A six degree of freedom manipulator was designed to place a clamp around the lugs and tighten it. The manipulator was fitted with the three fixed cameras but required another surveillance manipulator positioned in an adjacent standpipe to provide additional views. The need to prepare two standpipes limited the rate at which reinforcements could be made. Therefore an articulated two arm camera manipulator, which could be used on the existing manipulator mast was designed and built. The two manipulators were driven from separate desks and were controlled by the same supervisory computer linked to online graphics. The camera arm joints were driven on preplanned routes using a single joystick because of the complex moves and tight spaces involved. A large number of GTA sites have now been reinforced including a dropped GTA which had to be raised to carry out clamping. (Author)

  2. Special Gripper for a Robotic Arm

    Directory of Open Access Journals (Sweden)

    Miguel Angel SELLES

    2012-12-01

    Full Text Available New structures for gripping objects in robotic manipulation processes are oriented to the new arrangement of mechanical structures using new materials and processing technologies and innovative procedures for the implementation of contact gripping element links to an object with a high degree of adaptively of applications together with the ability to alter the structure of grip and limiting the intensity of the contact stiffness variation of snap elements custody and pliability. The application of elastomeric materials and surface finishes is important. This paper presents both a new gripper design for robot arms but also the search of the selected materials to make an experimental evaluation of technical parameters that are used to assess their application potential and suitability for the targeted applications. Also the results and conclusions for gripper testing in manipulation operations with two different robot arms are presented.

  3. Beam manipulating by metallic nano-slits with variant widths.

    Science.gov (United States)

    Shi, Haofei; Wang, Changtao; Du, Chunlei; Luo, Xiangang; Dong, Xiaochun; Gao, Hongtao

    2005-09-05

    A novel method is proposed to manipulate beam by modulating light phase through a metallic film with arrayed nano-slits, which have constant depth but variant widths. The slits transport electro-magnetic energy in the form of surface plasmon polaritons (SPPs) in nanometric waveguides and provide desired phase retardations of beam manipulating with variant phase propagation constant. Numerical simulation of an illustrative lens design example is performed through finite-difference time-domain (FDTD) method and shows agreement with theory analysis result. In addition, extraordinary optical transmission of SPPs through sub-wavelength metallic slits is observed in the simulation and helps to improve elements' energy using factor.

  4. Manipulative Properties of Asymmetric Double Quantum Dots via Laser and Gate Voltage

    International Nuclear Information System (INIS)

    Shun-Cai, Zhao; Zheng-Dong, Liu

    2009-01-01

    We present a density matrix approach for the theoretical description of an asymmetric double quantum dot (QD) system. The results show that the properties of gain, absorption and dispersion of the double QD system, the population of the state with one hole in one dot and an electron in another dot transferred by tunneling can be manipulated by a laser pulse or gate voltage. Our scheme may demonstrate the possibility of electro-optical manipulation of quantum systems. (condensed matter: electronicstructure, electrical, magnetic, and opticalproperties)

  5. A digital joint controller for manipulators

    International Nuclear Information System (INIS)

    Holt, E.J.; Palmer, D.E.B.

    1993-01-01

    Nuclear Electric's hydraulic heavy duty manipulators are used at a number of Magnox Power Stations for a wide variety of tasks. In recent years there has been a trend towards the use of manipulators for tasks requiring increasing precision of tip positioning. In order to meet this requirement, a digital controller has been designed to replace the analogue controller board used in almost all manipulator control systems. The new controller allows the programming of a wide range of closed loop control algorithms. Position and drive signal data may be passed to and from the controller by digital means, allowing direct connection to a graphical display system and/or a computer executing a guidance algorithm. The hardware and software design are outlined and performance in the laboratory and the field is reported. (author)

  6. MODULAR MANIPULATOR FOR ROBOTICS APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Joseph W. Geisinger, Ph.D.

    2001-07-31

    ARM Automation, Inc. is developing a framework of modular actuators that can address the DOE's wide range of robotics needs. The objective of this effort is to demonstrate the effectiveness of this technology by constructing a manipulator from these actuators within a glovebox for Automated Plutonium Processing (APP). At the end of the project, the system of actuators was used to construct several different manipulator configurations, which accommodate common glovebox tasks such as repackaging. The modular nature and quickconnects of this system simplify installation into ''hot'' boxes and any potential modifications or repair therein. This work focused on the development of self-contained robotic actuator modules including the embedded electronic controls for the purpose of building a manipulator system. Both of the actuators developed under this project contain the control electronics, sensors, motor, gear train, wiring, system communications and mechanical interfaces of a complete robotics servo device. Test actuators and accompanying DISC{trademark}s underwent validation testing at The University of Texas at Austin and ARM Automation, Inc. following final design and fabrication. The system also included custom links, an umbilical cord, an open architecture PC-based system controller, and operational software that permitted integration into a completely functional robotic manipulator system. The open architecture on which this system is based avoids proprietary interfaces and communication protocols which only serve to limit the capabilities and flexibility of automation equipment. The system was integrated and tested in the contractor's facility for intended performance and operations. The manipulator was tested using the full-scale equipment and process mock-ups. The project produced a practical and operational system including a quantitative evaluation of its performance and cost.

  7. Monolithic micro-electro-thermal actuator integrated with a lateral displacement sensor

    International Nuclear Information System (INIS)

    Zhang, Yan; Choi, Young-Soo; Lee, Dong-Weon

    2010-01-01

    This paper presents monolithically fabricated horizontal thermal actuators integrated with piezoresistive sensors for in situ displacement sensing. The great advantage of a hybrid system is the use of closed feedback control for improving the transient response of a thermal actuator and positioning accuracy. It consists of two 'hot arms' made of doped silicon for Joule heating-induced thermal expansion when a current flow passes through them. The piezoresistor is embedded in the base of the 'cold arm' flexure for monitoring the tip deflection and for performance characterization. This 'cold arm' is not a part of the electrical circuit, which further improves the heat power efficiency and the measurement accuracy. Optimization is achieved mainly through modification of the geometry as well as the fabrication process. The fabricated micro-electro-thermal actuator with an integrated sensor is intended for use as a scanning cantilever in atomic force microscope or as a sample holder to drive the moving object through arrays configuration.

  8. Probabilistic approach to manipulator kinematics and dynamics

    International Nuclear Information System (INIS)

    Rao, S.S.; Bhatti, P.K.

    2001-01-01

    A high performance, high speed robotic arm must be able to manipulate objects with a high degree of accuracy and repeatability. As with any other physical system, there are a number of factors causing uncertainties in the behavior of a robotic manipulator. These factors include manufacturing and assembling tolerances, and errors in the joint actuators and controllers. In order to study the effect of these uncertainties on the robotic end-effector and to obtain a better insight into the manipulator behavior, the manipulator kinematics and dynamics are modeled using a probabilistic approach. Based on the probabilistic model, kinematic and dynamic performance criteria are defined to provide measures of the behavior of the robotic end-effector. Techniques are presented to compute the kinematic and dynamic reliabilities of the manipulator. The effects of tolerances associated with the various manipulator parameters on the reliabilities are studied. Numerical examples are presented to illustrate the procedures

  9. Micro manipulators to handle micro machines. ; Aiming at developing clever and deft robots. Micro machine wo handling surutameno micro manipulator. ; Kashikoku kiyo na robot kaihatsu wo mezashite

    Energy Technology Data Exchange (ETDEWEB)

    Fujie, M [Hitachi, Ltd., Tokyo (Japan)

    1991-11-15

    The current state of micro manipulators (MM) to control micro machines is described. No MM can be realized with the conventional robots of which finger positions and attitudes are controlled by information on angles of each articulate. To solve this problem, such a system using the conception called a master slave manipulator with complex structure is proposed, in which human ways of manipulation are coupled with master arms with simple structure and slave arms facilitating works via a computer. The MM requires a flexible articulate chaining mechanism when the considerations on smallness of the arm structure and chaining of the multiple actuators are taken. To control the relative positions and attitudes, development of the control algorithm is required, which can learn the command signals given to a large number of actuators to drive mechanisms with ultra high freedoms and the relationship among changes in the end effector movements, rotation and directions, and can perform works according to precise relative positioning of objects to be handled. 8 refs., 4 figs.

  10. High precision redundant robotic manipulator

    International Nuclear Information System (INIS)

    Young, K.K.D.

    1998-01-01

    A high precision redundant robotic manipulator for overcoming contents imposed by obstacles or imposed by a highly congested work space is disclosed. One embodiment of the manipulator has four degrees of freedom and another embodiment has seven degrees of freedom. Each of the embodiments utilize a first selective compliant assembly robot arm (SCARA) configuration to provide high stiffness in the vertical plane, a second SCARA configuration to provide high stiffness in the horizontal plane. The seven degree of freedom embodiment also utilizes kinematic redundancy to provide the capability of avoiding obstacles that lie between the base of the manipulator and the end effector or link of the manipulator. These additional three degrees of freedom are added at the wrist link of the manipulator to provide pitch, yaw and roll. The seven degrees of freedom embodiment uses one revolute point per degree of freedom. For each of the revolute joints, a harmonic gear coupled to an electric motor is introduced, and together with properly designed based servo controllers provide an end point repeatability of less than 10 microns. 3 figs

  11. Design of mechanical arm for an automatic sorting system of recyclable cans

    Science.gov (United States)

    Resti, Y.; Mohruni, A. S.; Burlian, F.; Yani, I.; Amran, A.

    2018-04-01

    The use of a mechanical arm for an automatic sorting system of used cans should be designed carefully. The right design will result in a high precision sorting rate and a short sorting time. The design includes first; design manipulator,second; determine link and joint specifications, and third; build mechanical systems and control systems. This study aims to design the mechanical arm as a hardware system for automatic cans sorting system. The material used for the manipulator is the aluminum plate. The manipulator is designed using 6 links and 6 join where the 6th link is the end effectorand the 6th join is the gripper. As a driving motor used servo motor, while as a microcontroller used Arduino Uno which is connected with Matlab programming language. Based on testing, a mechanical arm designed for this recyclable canned recycling system has a precision sorting rate at 93%, where the average total time required for sorting is 10.82 seconds.

  12. Dynamic Modelling for Planar Extensible Continuum Robot Manipulators

    Science.gov (United States)

    2006-01-01

    to the OCTARM continuum ma- nipulator. The OCTARM manipulator is a biologically inspired soft robot manipulator resembling an elephant trunk or an... octopus arm [18]. The OCTARM, shown in Figure 1, is a three-section robot with nine degrees of freedom. Aside from two axis bending with constant...increasing interest in designing �biologically inspired � continuum robots . Some of these designs are mimicking trunks [8], [25], tentacles [17], [21], [24

  13. Modelling of Moving Coil Actuators in Fast Switching Valves Suitable for Digital Hydraulic Machines

    DEFF Research Database (Denmark)

    Nørgård, Christian; Roemer, Daniel Beck; Bech, Michael Møller

    2015-01-01

    an estimation of the eddy currents generated in the actuator yoke upon current rise, as they may have significant influence on the coil current response. The analytical model facilitates fast simulation of the transient actuator response opposed to the transient electro-magnetic finite element model which......The efficiency of digital hydraulic machines is strongly dependent on the valve switching time. Recently, fast switching have been achieved by using a direct electromagnetic moving coil actuator as the force producing element in fast switching hydraulic valves suitable for digital hydraulic...... machines. Mathematical models of the valve switching, targeted for design optimisation of the moving coil actuator, are developed. A detailed analytical model is derived and presented and its accuracy is evaluated against transient electromagnetic finite element simulations. The model includes...

  14. Electro photographic materials

    International Nuclear Information System (INIS)

    Buzdugan, A.; Andries, A.; Iovu, M.

    2000-01-01

    The invention relates to the creation of electro photographic materials . The invention allows to extend the material photosensitivity into the infrared range of the spectrum. An electro photographic materials contains an electro conducting base, including a dielectric base 1, for example glass, an electro conducting layer 2, for example of Al, Ni, Cr, an injecting layer 3, consisting of amorphous indium phosphide, a vitreous layer 4 of the arsenic sulphide - antimony sulphide system and a transporting layer 5 of the arsenic sulphide or arsenic selenide

  15. Sensory-Feedback Exoskeletal Arm Controller

    Science.gov (United States)

    An, Bin; Massie, Thomas H.; Vayner, Vladimir

    2004-01-01

    An electromechanical exoskeletal arm apparatus has been designed for use in controlling a remote robotic manipulator arm. The apparatus, called a force-feedback exoskeleton arm master (F-EAM) is comfortable to wear and easy to don and doff. It provides control signals from the wearer s arm to a robot arm or a computer simulator (e.g., a virtual-reality system); it also provides force and torque feedback from sensors on the robot arm or from the computer simulator to the wearer s arm. The F-EAM enables the wearer to make the robot arm gently touch objects and finely manipulate them without exerting excessive forces. The F-EAM features a lightweight design in which the motors and gear heads that generate force and torque feedback are made smaller than they ordinarily would be: this is achieved by driving the motors to power levels greater than would ordinarily be used in order to obtain higher torques, and by providing active liquid cooling of the motors to prevent overheating at the high drive levels. The F-EAM (see figure) includes an assembly that resembles a backpack and is worn like a backpack, plus an exoskeletal arm mechanism. The FEAM has five degrees of freedom (DOFs) that correspond to those of the human arm: 1. The first DOF is that of the side-to-side rotation of the upper arm about the shoulder (rotation about axis 1). The reflected torque for this DOF is provided by motor 1 via drum 1 and a planar four-bar linkage. 2. The second DOF is that of the up-and-down rotation of the arm about the shoulder. The reflected torque for this DOF is provided by motor 2 via drum 2. 3. The third DOF is that of twisting of the upper arm about its longitudinal axis. This DOF is implemented in a cable remote-center mechanism (CRCM). The reflected torque for this DOF is provided by motor 3, which drives the upper-arm cuff and the mechanism below it. A bladder inflatable by gas or liquid is placed between the cuff and the wearer s upper arm to compensate for misalignment

  16. Telerobotic control of a dextrous manipulator using master and six-DOF hand-controllers for space assembly and servicing tasks

    Science.gov (United States)

    O'Hara, John M.

    1987-01-01

    Two studies were conducted evaluating methods of controlling a telerobot; bilateral force reflecting master controllers and proportional rate six degrees of freedom (DOF) hand controllers. The first study compared the controllers on performance of single manipulator arm tasks, a peg-in-the-hole task, and simulated satellite orbital replacement unit changeout. The second study, a Space Station truss assembly task, required simultaneous operation of both manipulator arms (all 12 DOFs) and complex multiaxis slave arm movements. Task times were significantly longer and fewer errors were committed with the hand controllers. The hand controllers were also rated significantly higher in cognitive and manual control workload on the two-arm task. The master controllers were rated significantly higher in physical workload. There were no significant differences in ratings of manipulator control quality.

  17. Manipulator for inspection or repair of heat exchanger tubes, in particular in steam generators for nuclear reactors

    International Nuclear Information System (INIS)

    Gugel, G.

    1979-01-01

    The manipulator used to inspect or repair pipes in the steam generator chamber of a PWR can be introduced and removed through a penetration nozzle which can be sealed tightly by means of a blind flange. The front end of the manipulator carries a swivel arm which can be operated remotely to be moved in a plane parallel to the tube plate. The end of the swivel arm carries a holder for a mouthpiece which can be extended and retracted. This carrier can also be operated remotely so as to be aligned to the pipe orifices in a direction normal to the swivel plane of the swivel arm. The manipulator is supported in antifriction bearings in the penetration nozzle so as to be movable longitudinally. (DG) [de

  18. Remote telerobotic replacement for master-slave manipulator

    International Nuclear Information System (INIS)

    Heckendorn, F.M.; Iverson, D.C.; LaValle, D.R.

    1997-01-01

    A remotely replaceable telerobotic manipulator (TRM) has been developed and deployed at the Defense Waste Processing Facility (DWPF) in support of its radioactive operation. The TRM replaces a Master-Slave Manipulator (MSM). The TRM is in use for both routine and recovery operations for the radioactive waste vitrification melter, the primary production device within the DWPF. The arm was designed for deployment and operation using an existing MSM penetration. This replacement of an existing MSM with a high power robotic device demonstrates the capability to perform similar replacement in other operating facilities. The MSM's were originally deployed in the DWPF to perform routine light capacity tasks. During the testing phase of the DWPF, prior to its radioactive startup in 5/96, the need to remove glass deposits that can form at the melter discharge during filling of glass containment canisters was identified. The combination of high radiation and contamination in the DWPF melter cell during radioactive operation eliminated personnel entry as a recovery option. Therefore remote cleaning methods had to be devised. The MSM's had neither the reach nor the strength required for this task. It became apparent that a robust manipulator arm would be required for recovery from these potential melter discharge pluggage events. The existing wall penetrations, used for the MSM's, could not be altered for seismic and radiological reasons. The new manipulator was required to be of considerable reach, due to existing physical layout, and strength, due to the glass removal requirement. Additionally, the device would have to compatible with high radiation and remote crane installation. The physical size of the manipulator and the weight of components must be consistent with the existing facilities. It was recognized early-on that a manipulator of sufficient strength to recover from a pluggage event would require robotic functions to constrain undesirable motions

  19. Making planned paths look more human-like in humanoid robot manipulation planning

    DEFF Research Database (Denmark)

    Zacharias, F.; Schlette, C.; Schmidt, F.

    2011-01-01

    It contradicts the human's expectations when humanoid robots move awkwardly during manipulation tasks. The unnatural motion may be caused by awkward start or goal configurations or by probabilistic path planning processes that are often used. This paper shows that the choice of an arm's target...... for the robot arm....

  20. A combined impedance-PD approach for controlling a dual-arm space manipulator in the capture of a non-cooperative target

    Science.gov (United States)

    Stolfi, A.; Gasbarri, P.; Sabatini, M.

    2017-10-01

    In the near future robotic systems will be playing an increasingly important role in space applications such as repairing, refueling, re-orbiting spacecraft and cleaning up the increasing amount of space debris. Space Manipulator Systems (SMSs) are robotic systems made of a platform (which has its own actuators such as thrusters and reaction wheels) equipped with one or more deployable arms. The present paper focuses on the issue of maintaining a stable first contact between the arms terminal parts (i.e. the end-effectors) and a target satellite, before the actual grasp is performed. The selected approach is a modified version of the Impedance Control algorithm, in which the end-effector is controlled in order to make it behave like a mass-spring-damper system regardless of the reaction motion of the base, so to absorb the impact energy. The usual approach consists in considering a point mass target and one-dimensional contact dynamics; however, the contact between the chaser and the target could generate a perturbation on the attitude of the target. On account of this, in the present work a more realistic scenario, consisting in a 2D rigid target and a relevant 2D contact dynamics, is considered. A two-arm configuration of the SMS is modelled and its effectiveness analyzed. The performance of the proposed control architecture is evaluated by means of a co-simulation involving the MSC Adams multibody code (for describing the dynamics of the space robot and target) together with Simulink (for the determination of the control actions). The co-simulation is a particularly useful tool to implement robust control applied to detailed dynamic systems. Several numerical results complete the work.

  1. Large displacement spring-like electro-mechanical thermal actuators with insulator constraint beams

    Science.gov (United States)

    Luo, J. K.; Fu, Y. Q.; Flewitt, A. J.; Spearing, S. M.; Fleck, N. A.; Milne, W. I.

    2005-07-01

    A number of in-plane spring-like micro-electro-thermal-actuators with large displacements were proposed. The devices take the advantage of the large difference in the thermal expansion coefficients between the conductive arms and the insulator clamping beams. The constraint beams in one type (the spring) of these devices are horizontally positioned to restrict the expansion of the active arms in the x-direction, and to produce a displacement in the y-direction only. In other two types of actuators (the deflector and the contractor), the constraint beams are positioned parallel to the active arms. When the constraint beams are on the inside of the active arms, the actuator produces an outward deflection in the y-direction. When they are on the outside of the active arms, the actuator produces an inward contraction. Analytical model and finite element analysis were used to simulate the performances. It showed that at a constant temperature, analytical model is sufficient to predict the displacement of these devices. The displacements are all proportional to the temperature and the number of the chevron sections. A two-mask process is under development to fabricate these devices, using Si3N4 as the insulator beams, and electroplated Ni as the conductive beams.

  2. Electro-mechanical control of an on-chip optical beam splitter containing an embedded quantum emitter.

    Science.gov (United States)

    Bishop, Z K; Foster, A P; Royall, B; Bentham, C; Clarke, E; Skolnick, M S; Wilson, L R

    2018-05-01

    We demonstrate electro-mechanical control of an on-chip GaAs optical beam splitter containing a quantum dot single-photon source. The beam splitter consists of two nanobeam waveguides, which form a directional coupler (DC). The splitting ratio of the DC is controlled by varying the out-of-plane separation of the two waveguides using electromechanical actuation. We reversibly tune the beam splitter between an initial state, with emission into both output arms, and a final state with photons emitted into a single output arm. The device represents a compact and scalable tuning approach for use in III-V semiconductor integrated quantum optical circuits.

  3. End-Effector Position Analysis Using Forward Kinematics For 5 Dof Pravak Robot Arm

    OpenAIRE

    Jolly Atit Shah; S.S. Rattan; B.C. Nakra

    2013-01-01

    Automatic control of the robotic manipulator involves study of kinematics and dynamics as a major issue. This paper involves the kinematic analysis of a Pravak Robot arm which is used for doing successful robotic manipulation task in its workspace. The Pravak Robot Arm is a 5-DOF robot having all the joints revolute. The kinematics problem is defined as the transformation from the Cartesian space to the joint space and vice versa. In this study the Denavit- Hartenberg (D-H) model is used to m...

  4. Design of turning hydraulic engines for manipulators of mobile machines on the basis of multicriterial optimization

    Directory of Open Access Journals (Sweden)

    Lagerev I.A.

    2016-12-01

    Full Text Available In this paper the mathematical models of the main types of turning hydraulic engines, which at the present time widely used in the construction of handling systems of domestic and foreign mobile transport-technological machines wide functionality. They allow to take into consideration the most significant from the viewpoint of ensuring high technical-economic indicators of hydraulic efficiency criteria – minimum mass (weight, their volume and losses of power. On the basis of these mathematical models the problem of multicriterial constrained optimization of the constructive sizes of turning hydraulic engines are subject to complex constructive, strength and deformation limits. It allows you to de-velop the hydraulic engines in an optimized design which is required for the purpose of designing a comprehensive measure takes into account efficiency criteria. The multicriterial optimization problem is universal in nature, so when designing a turning hydraulic engines allows for one-, two - and three-criteria optimization without making any changes in the solution algorithm. This is a significant advantage for the development of universal software for the automation of design of mobile transport-technological machines.

  5. Design and experimental evaluation of flexible manipulator control algorithms

    International Nuclear Information System (INIS)

    Kwon, D.S.; Hwang, D.H.; Babcock, S.M.; Kress, R.L.

    1995-01-01

    Within the Environmental Restoration and Waste Management Program of the US Department of Energy, the remediation of single-shell radioactive waste storage tanks is one of the areas that challenge state-of-the-art equipment and methods. The use of long-reach manipulators is being seriously considered for this task. Because of high payload capacity and high length-to-cross-section ratio requirements, these long-reach manipulator systems are expected to use hydraulic actuators and to exhibit significant structural flexibility. The controller has been designed to compensate for the hydraulic actuator dynamics by using a load-compensated velocity feedforward loop and to increase the bandwidth by using an inner pressure feedback loop. Shaping filter techniques have been applied as feedforward controllers to avoid structural vibrations during operation. Various types of shaping filter methods have been investigated. Among them, a new approach, referred to as a ''feedforward simulation filter'' that uses embedded simulation, has been presented

  6. Influence of heart rhythm, breathing and arm position during computed tomography scanning on the registration accuracy of electro anatomical map (EAM) images, left atrium three-dimensional computed tomography angiography images, and fluoroscopy time during ablation to treat atrial fibrillation

    International Nuclear Information System (INIS)

    Chono, Taiki; Shimoshige, Shinya; Yoshikawa, Kenta; Mizonobe, Kazuhusa; Ogura, Keishi

    2013-01-01

    In CARTOMERGE for treatment of atrial fibrillation (AF) by ablation, by integrating electro anatomical map (EAM) and left atrium three-dimensional computed tomography angiography (3D-CTA) images, identification of the ablation points is simplified and the procedure can be made carried out more rapidly. However, the influence that heart rhythm, breathing and arm position during CT scanning have on registration accuracy and fluoroscopy time is not clear. To clarify the influence on registration accuracy and fluoroscopy time of heart rhythm, breathing and arm position during CT scanning. The patients were CT-scanned during both sinus rhythm (SR) and AF in each study subject. We evaluated the registration accuracy of images reconstructed between the cardiac cycle and assessed the registration accuracy and fluoroscopy time of images obtained during inspiratory breath-hold, expiratory breath-hold and up and down position of the arm. Although the registration accuracy of the EAM image and left atrium 3D-CTA image showed a significant difference during SR, no significant difference was seen during AF. Expiratory breath-hold and down position of the arm resulted in the highest registration accuracy and the shortest fluoroscopy time. However, arm position had no significant effect on registration accuracy. Heart rhythm and breathing during CT scanning have a significant effect on the registration accuracy of EAM images, left atrium 3D-CTA images, and fluoroscopy time. (author)

  7. Self-repairing control for damaged robotic manipulators

    International Nuclear Information System (INIS)

    Eisler, G.R.; Robinett, R.D.; Dohrmann, C.R.; Driessen, B.J.

    1997-03-01

    Algorithms have been developed allowing operation of robotic systems under damaged conditions. Specific areas addressed were optimal sensor location, adaptive nonlinear control, fault-tolerant robot design, and dynamic path-planning. A seven-degree-of-freedom, hydraulic manipulator, with fault-tolerant joint design was also constructed and tested. This report completes this project which was funded under the Laboratory Directed Research and Development program

  8. Electro-Deposition Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The electro-deposition laboratory can electro-deposit various coatings onto small test samples and bench level prototypes. This facility provides the foundation for...

  9. Learning the inverse kinetics of an octopus-like manipulator in three-dimensional space.

    Science.gov (United States)

    Giorelli, M; Renda, F; Calisti, M; Arienti, A; Ferri, G; Laschi, C

    2015-05-13

    This work addresses the inverse kinematics problem of a bioinspired octopus-like manipulator moving in three-dimensional space. The bioinspired manipulator has a conical soft structure that confers the ability of twirling around objects as a real octopus arm does. Despite the simple design, the soft conical shape manipulator driven by cables is described by nonlinear differential equations, which are difficult to solve analytically. Since exact solutions of the equations are not available, the Jacobian matrix cannot be calculated analytically and the classical iterative methods cannot be used. To overcome the intrinsic problems of methods based on the Jacobian matrix, this paper proposes a neural network learning the inverse kinematics of a soft octopus-like manipulator driven by cables. After the learning phase, a feed-forward neural network is able to represent the relation between manipulator tip positions and forces applied to the cables. Experimental results show that a desired tip position can be achieved in a short time, since heavy computations are avoided, with a degree of accuracy of 8% relative average error with respect to the total arm length.

  10. Whole-arm obstacle avoidance system conceptual design

    International Nuclear Information System (INIS)

    Wintenberg, A.L.; Butler, P.L.; Babcock, S.M.; Ericson, M.N.; Britton, C.L. Jr.

    1993-04-01

    Whole-arm obstacle avoidance is needed for a variety of robotic applications in the Environmental Restoration and Waste Management (ER ampersand WM) Program. Typical industrial applications of robotics involve well-defined workspaces, allowing a predetermined knowledge of collision-free paths for manipulator motion. In the unstructured or poorly defined hazardous environments of the ER ampersand WM Program, the potential for significant problems resulting from collisions between manipulators and the environment in which they are utilized is great. The conceptual design for a sensing system that will provide protection against such collisions is described herein. The whole-arm obstacle avoidance system consists of a set of sensor ''bracelets,'' which cover the surface area of the manipulator links to the maximum extent practical, and a host processor. The host processor accepts commands from the robot control system, controls the operation of the sensors, manipulates data received from the bracelets, and makes the data available to the manipulator control system. The bracelets consist of a subset of the sensors, associated sensor interface electronics, and a bracelet interface. Redundant communications links between the host processor and the bracelets are provided, allowing single-point failure protection. The system allows reporting of 8-bit data from up to 1000 sensors at a minimum of 50 Hz. While the initial prototype implementation of the system utilizes capacitance proximity sensor, the system concept allows multiple types of sensors. These sensors are uniquely addressable, allowing remote calibration, thresholding at the bracelet, and correlation of a sensor measurement with the associated sensor and its location on the manipulator. Variable resolution allows high-speed, single-bit sensing as well as lower-speed higher-resolution sensing, which is necessary for sensor calibration and potentially useful in control

  11. Environmental effects monitoring at Cat Arm Hydraulic Development, Newfoundland, Canada

    International Nuclear Information System (INIS)

    Hill, E.L.

    1988-01-01

    The Cat Arm Dam is located on a plateau of the Long Range Mountains on Newfoundland's Great Northern Peninsula, and the 127 MW unit uses a 387 m head to produce an average of 676 GWh annually. Newfoundland and Labrador Hydro is conducting an environmental effects monitoring program in Cat Arm Reservoir to evaluate environmental impacts of the project. In the addendum to the Environmental Impact Statement of 1981, the utility agreed to a number of actions to mitigate the impacts of construction on fish populations, and to monitor the effects of reservoir creation, including the following. The mercury content of fish flesh, sediments and water would be monitored, and sampling would be undertaken prior to flooding to obtain baseline data, and for at least five years after flooding. The brook trout population would be monitored at various stages in the life of the reservoir in order to detect negative changes for which mitigative strategies could be applied. Alternative spawning habitat would be provided by removing barriers on streams or creating spawning beds if the monitoring program showed that recruitment was falling, and if these methods were ineffective, a compensatory stocking program would be considered. Extensive monitoring would be undertaken of the littoral zones, primary production in the reservoir, and of a number of limnological parameters to document long term changes in the reservoir. Although of academic interest, certain unusual characteristics of the Cat Arm reservoir, such as its low pH and dark colour, reduce its utility as a predictor of changes due to reservoir formation elsewhere in Newfoundland. 15 refs., 1 fig

  12. A portable modular architecture for robotic manipulator control

    International Nuclear Information System (INIS)

    Butler, P.L.

    1993-01-01

    A control architecture has been developed to provide a framework for robotic manipulator control. This architecture, called the Modular Integrated Control Architecture (MICA), has been successfully applied to two different manipulator systems. MICA is a portable system in two respects. First, it can be used for the control of different types of manipulator systems. Second, the MICA code is portable across several operating environments. This portability allows the sharing of common control code among various systems. A major portion of MICA is the precise control of multiple processors that have to be coordinated to control a manipulator system. By having NUCA control the processor synchronization, the system developer can concentrate on the specific aspects of a new manipulator system. MICA also provides standard functions for trajectory generation that can be used for most manipulators. Custom trajectory generators can be easily added to suit the needs of a particular robotic control system. Another facility that MICA provides is a simulation of the manipulator, allowing the control code to be simulated before trying it on a manipulator system. Using this technique, one can develop code for a manipulator system without risking damage to the arm during development

  13. Electro-optical switching of liquid crystals of graphene oxide

    Science.gov (United States)

    Song, Jang-Kun

    Electric field effects on aqueous graphene-oxide (GO) dispersions are reviewed in this chapter. In isotropic and biphasic regimes of GO dispersions, in which the inter-particle friction is low, GO particles sensitively respond to the application of electric field, producing field-induced optical birefringence. The electro-optical sensitivity dramatically decreases as the phase transits to the nematic phase; the increasing inter-particle friction hinders the rotational switching of GO particles. The corresponding Kerr coefficient reaches the maximum near the isotropic to biphasic transition concentration, at which the Kerr coefficient is found be c.a. 1:8 · 10-5 mV-2, the highest value ever reported in all Kerr materials. The exceptionally large Kerr effect arises from the Maxwell- Wagner polarization of GO particles with an extremely large aspect ratio and a thick electrical double layer (EDL). The polarization sensitively depends on the ratio of surface and bulk conductivities in dispersions. As a result, low ion concentration in bulk solvent is highly required to achieve a quality electro-optical switching in GO dispersions. Spontaneous vinylogous carboxylic reaction in GO particles produces H+ ions, resulting in spontaneous degradation of electro-optical response with time, hence the removal of residual ions by using a centrifuge cleaning process significantly improves the electro-optical sensitivity. GO particle size is another important parameter for the Kerr coefficient and the response time. The best performance is observed in a GO dispersion with c.a. 0.5 μm mean size. Dielectrophoretic migration of GO particles can be also used to manipulate GO particles in solution. Using these unique features of GO dispersions, one can fabricate GO liquid crystal devices similar to conventional liquid crystal displays; the large Kerr effect allows fabricating a low power device working at extremely low electric fields.

  14. Dual Arm Work Module Development and Appplications

    Energy Technology Data Exchange (ETDEWEB)

    Noakes, M.W.

    1999-04-25

    The dual arm work module (DAWM) was developed at Oak Ridge National Laboratory (ORNL) by the Robotics Technology Development Program (RTDP) as a development test bed to study issues related to dual arm manipulation, including platform cotilguration, controls, automation, operations, and tooling. The original platform was based on two Schilling Titan II manipulators mounted to a 5-degree-of- freedom (DOF) base fabricated by RedZone Robotics, Inc. The 5-DOF articulation provided a center torso rotation, linear actuation to change the separation between the arms, and arm base rotation joints to provide "elbows up," elbows down," or "elbows out" orientation. A series of tests were conducted on operations, tooling, and task space scene analysis (TSSA)-driven robotics for overhead transporter- mounted and crane hook-deployed scenarios. A concept was developed for DAWM deployment from a large remote work vehicle, but the project was redirected to support dismantlement of the Chicago Pile #5 (CP-5) reactor at Argonne National Laboratory in fiscal year (FY) 1997. Support of CP-5 required a change in focus of the dual arm technology from that of a development test bed to a system focussed for a specific end user. ORNL teamed with the Idaho National Environmental ,Engineering Laboratory, Sandia National Laboratory, and the Savannah River Technology Center to deliver a crane-deployed derivative of the DAWM, designated the dual arm work platform (DAWP). RTDP staff supported DAWP at CP-5 for one FY; Argonne staff continued operation through to dismantlement of the reactor internals. Lessons learned from this interaction were extensive. Beginning in FY 1999, dual arm development activities are again being pursued in the context of those lessons learned. This paper describes the progression of philosophy of the DAWM from initial test bed to lessons learned through interaction at CP-5 and to the present investigation of telerobotic assist of teleoperation and TSSA- driven robotics.

  15. Towards holonomic electro-elastomer actuators with six degrees of freedom

    International Nuclear Information System (INIS)

    Conn, A T; Rossiter, J

    2012-01-01

    Functionally efficient six degree of freedom (DOF) actuators have not yet been developed in a scale-invariant and inherently compliant unified form. This has primarily been due to the use of conventional serial or parallel kinematical configurations and electromagnetic motors, pneumatics and hydraulics. Contrary to traditional technologies, utilizing electro-active elastomers enables multi-DOF actuation and holonomic operation with minimal structural complexity. Conical dielectric elastomer actuators (DEAs) are compact multi-DOF actuator–sensors that are scalable and can be entirely polymeric, making them suitable for a variety of applications including minimally invasive medical devices. In this paper, cone DEAs are developed towards integrated 6-DOF actuation with muscle-like performance from a single structure. This is achieved by demonstrating the feasibility of holonomic 6-DOF actuation and through experimental characterization of a 5-DOF prototype. The 5-DOF prototype (50 mm length, 60 mm diameter) produced rotational actuation outputs of ±21.7° and ±9.42 mN m and linear actuation outputs of ±4.45 mm (±9.1%) and ±0.55 N. Finally, combined multi-DOF actuation is demonstrated as part of development towards scalable holonomic electro-active elastomer actuators. (paper)

  16. Towards holonomic electro-elastomer actuators with six degrees of freedom

    Science.gov (United States)

    Conn, A. T.; Rossiter, J.

    2012-03-01

    Functionally efficient six degree of freedom (DOF) actuators have not yet been developed in a scale-invariant and inherently compliant unified form. This has primarily been due to the use of conventional serial or parallel kinematical configurations and electromagnetic motors, pneumatics and hydraulics. Contrary to traditional technologies, utilizing electro-active elastomers enables multi-DOF actuation and holonomic operation with minimal structural complexity. Conical dielectric elastomer actuators (DEAs) are compact multi-DOF actuator-sensors that are scalable and can be entirely polymeric, making them suitable for a variety of applications including minimally invasive medical devices. In this paper, cone DEAs are developed towards integrated 6-DOF actuation with muscle-like performance from a single structure. This is achieved by demonstrating the feasibility of holonomic 6-DOF actuation and through experimental characterization of a 5-DOF prototype. The 5-DOF prototype (50 mm length, 60 mm diameter) produced rotational actuation outputs of ±21.7° and ±9.42 mN m and linear actuation outputs of ±4.45 mm (±9.1%) and ±0.55 N. Finally, combined multi-DOF actuation is demonstrated as part of development towards scalable holonomic electro-active elastomer actuators.

  17. System and method for controlling engine knock using electro-hydraulic valve actuation

    Science.gov (United States)

    Brennan, Daniel G

    2013-12-10

    A control system for an engine includes a knock control module and a valve control module. The knock control module adjusts a period that one or more of an intake valve and an exhaust valve of a cylinder are open based on engine knock corresponding to the cylinder. The valve control module, based on the adjusted period, controls the one or more of the intake valve and the exhaust valve using one or more hydraulic actuators.

  18. An approach for second order control with finite time convergence for electro-hydraulic drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    algorithm parameters. However a discontinuous term internally in the control structure may excite pressures of transmission lines in hydraulic drives as the control structure strives to maintain the control error and its derivative equal to zero. In this paper a modified version of a controller based......Being a second order sliding algorithm, the super twisting algorithm is highly attractive for application in control of hydraulic drives and mechanical systems in general, as it utilizes only the control error while driving the control error as well as its derivative to zero for properly chosen...... on the super twisting algorithm is proposed, with the focus of eliminating the discontinuous term in order to achieve a more smooth control operation. The convergence properties of the proposed controller are analyzed via a conservative phase plane analysis. Furthermore, homogeneity considerations imply finite...

  19. Robust Position Tracking for Electro-Hydraulic Drives Based on Generalized Feedforward Compensation Approach

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2012-01-01

    This paper presents a robust tracking control concept based on accurate feedforward compensation for hydraulic valve-cylinder drives. The proposed feedforward compensator is obtained utilizing a generalized description of the valve flow that takes into account any asymmetry of valves and...... constant gain type feedforward compensator, when subjected to strong perturbations in supply pressure and coulomb friction....

  20. Proposal for electro-optic multiplier based on dual transverse electro-optic Kerr effect.

    Science.gov (United States)

    Li, Changsheng

    2008-10-20

    A novel electro-optic multiplier is proposed, which can perform voltage multiplication operation by use of the Kerr medium exhibiting dual transverse electro-optic Kerr effect. In this kind of Kerr medium, electro-optic phase retardation is proportional to the square of its applied electric field, and orientations of the field-induced birefringent axes are only related to the direction of the field. Based on this effect, we can design an electro-optic multiplier by selecting the crystals of 6/mmm, 432, and m3m classes and isotropic Kerr media such as glass. Simple calculation demonstrates that a kind of glass-ceramic material with a large Kerr constant can be used for the design of the proposed electro-optic multiplier.

  1. Kinematics at the Main Mechanism of a Railbound Forging Manipulator

    Directory of Open Access Journals (Sweden)

    Florian Ion Tiberiu Petrescu

    2015-09-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Heavy payload forging manipulators are mainly characterized by large load output and large capacitive load input. The relationship between outputs and inputs will greatly influence the control and the reliability. Forging manipulators have become more prevalent in the industry today. They are used to manipulate objects to be forged. The most common forging manipulators are moving on a railway to have a greater precision and stability. They have been called the railbound forging manipulators. In this paper we analyze the general kinematics of the main mechanism from a such manipulator. Kinematic scheme shows a typical forging manipulator, with the basic motions in operation process: walking, motion of the tong and buffering. The lifting mechanism consists of several parts including linkages, hydraulic drives and motion pairs. The principle of type design from the viewpoints of the relationship between output characteristics and actuator inputs is discussed. An idea of establishing the incidence relationship between output characteristics and actuator inputs is proposed. These novel forging manipulators which satisfy certain functional requirements provide an effective help for the design of forging manipulators.

  2. Development of a ROV titanium manipulator for light work class ROV vehicles

    OpenAIRE

    Garay, Gaizka X.; Sosa, Dario

    2016-01-01

    This paper shows the development of a high technical equipment to be used as tooling of submersible ROV (Remote Operated Vehicles) for offshore operations, particularly the design and fabrication by Additive Manufacturing (AM) of a Titanium Manipulator for ROVs. From the initial concept and design until a new formed company “TITANROB”, this document shortly describes the fabrication of hydraulic titanium manipulators for mid size ROV vehicles, the TitanRob series M501, G500 ...

  3. Remarks on manipulator classification and reversibility - deflection - backlash - inertia - balance and friction trade off

    International Nuclear Information System (INIS)

    Vertut, Jean.

    1976-01-01

    In a previous work the author proposed a time efficiency quotient based on time to perform a task for a man controlling a manipulator (RO MAN SY 73). This quotient is also a global evaluation of a man-manipulator system, and can be extended to teaching programmed manipulators. Classification based on this quotient emphasizes the importance of force feed-back to the operator, and enables to project the same concept to computer control. This paper concentrates on characteristics reflecting directly to the mechanics of the arm, to the actuators and to the control. They need delicate trade off: reversibility is key to force feed-back, deflection reflects on arm dynamics (oscillation) and precision, backlash allows lower friction but limits servo performances, inertia is high when limited deflection is required, friction is limiting the man in the loop performances, force transducers can compensate irreversibility and/or friction but lead to control sophistication. These trade offs are developed, and some proposed constants are given for force feed-back manipulators

  4. Nonlinear stability research on the hydraulic system of double-side rolling shear

    Science.gov (United States)

    Wang, Jun; Huang, Qingxue; An, Gaocheng; Qi, Qisong; Sun, Binyu

    2015-10-01

    This paper researches the stability of the nonlinear system taking the hydraulic system of double-side rolling shear as an example. The hydraulic system of double-side rolling shear uses unsymmetrical electro-hydraulic proportional servo valve to control the cylinder with single piston rod, which can make best use of the space and reduce reversing shock. It is a typical nonlinear structure. The nonlinear state-space equations of the unsymmetrical valve controlling cylinder system are built first, and the second Lyapunov method is used to evaluate its stability. Second, the software AMEsim is applied to simulate the nonlinear system, and the results indicate that the system is stable. At last, the experimental results show that the system unsymmetrical valve controlling the cylinder with single piston rod is stable and conforms to what is deduced by theoretical analysis and simulation. The construction and application of Lyapunov function not only provide the theoretical basis for using of unsymmetrical valve controlling cylinder with single piston rod but also develop a new thought for nonlinear stability evaluation.

  5. Development of 6-axis portable manipulator which traces over 3-dimensional curved surface for ultrasonic inspection

    International Nuclear Information System (INIS)

    Hayashi, Tetsuji; Tsuzuki, Satoshi; Tsunewaki, Hiroshi.

    1993-01-01

    A 6-axis portable manipulator, weighing 120 N (12.3 kg) which traces over a 3-dimensional curved surface for ultrasonic testing has been developed. The manipulator body is made of carbon-fiber-reinforced plastic and magnesium alloy. A feature of the system is that deviation of the manipulator from its nominal path caused by arm bending due to its own weight can be corrected. The deviation is calculated by premeasuring spring coefficients and hysteresis characteristics of the arm structure. In a mock-up calibration performance test the accuracy was shown to be as high as that of a human inspector. The manipulator can be installed within 3 minutes by a single person. Joint angles are calculated with a direct memory access (DMA) handler using a poling method. Signals are transmitted to servo-controllers through an optical fiber of 2.5 Mbps. (author)

  6. Strategies for redundancy resolution of dual-arm systems with passive elements for tank waste removal

    International Nuclear Information System (INIS)

    Dubey, R.

    1997-01-01

    The work described in this paper focuses on the coordination and control of two manipulators coupled by passive elements operating in a confined space. An example of one such system is the hardware used for the environmental response treatability study funded by the Department of Energy at Oak Ridge National Laboratory (ORNL). The motivation for this project is to establish the methodology necessary to extract large volumes of hazardous waste from underground storage facilities. The hardware used at ORNL consists of two long-reach manipulators. The first robot, the Modified Light Duty Utility Arm (MLDUA), is an 8-degree-of-freedom long-reach manipulator. The second arm, the Hose Management Arm (HMA), has two active degrees-of-freedom and provides hardware to break up and extract materials from the tank. Current strategies call for the MLDUA to grasp a combined sluicing end-effector attached, by a long flexible hose, to the HMA. The MLDUA will then move the combined system through the waste, extracting material. This paper describes many of the issues related to redundancy resolution and the coordinated control of these two robots. First, the authors provide a brief outline of the project and the existing hardware. This is followed by a description of existing redundancy resolution techniques and the impact redundancy has on the success of the project. Finally, preliminary simulation results show the effect cooperative control has on the level of forces generated between the dual-arm systems when coupled by an elastic exhaust hose. These results show a significant reduction in forces when both arms are active and have a combined manipulation strategy

  7. Strategies for redundancy resolution of dual-arm systems with passive elements for tank waste removal

    Energy Technology Data Exchange (ETDEWEB)

    Dubey, R. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Mechanical Engineering; Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States)

    1997-03-01

    The work described in this paper focuses on the coordination and control of two manipulators coupled by passive elements operating in a confined space. An example of one such system is the hardware used for the environmental response treatability study funded by the Department of Energy at Oak Ridge National Laboratory (ORNL). The motivation for this project is to establish the methodology necessary to extract large volumes of hazardous waste from underground storage facilities. The hardware used at ORNL consists of two long-reach manipulators. The first robot, the Modified Light Duty Utility Arm (MLDUA), is an 8-degree-of-freedom long-reach manipulator. The second arm, the Hose Management Arm (HMA), has two active degrees-of-freedom and provides hardware to break up and extract materials from the tank. Current strategies call for the MLDUA to grasp a combined sluicing end-effector attached, by a long flexible hose, to the HMA. The MLDUA will then move the combined system through the waste, extracting material. This paper describes many of the issues related to redundancy resolution and the coordinated control of these two robots. First, the authors provide a brief outline of the project and the existing hardware. This is followed by a description of existing redundancy resolution techniques and the impact redundancy has on the success of the project. Finally, preliminary simulation results show the effect cooperative control has on the level of forces generated between the dual-arm systems when coupled by an elastic exhaust hose. These results show a significant reduction in forces when both arms are active and have a combined manipulation strategy.

  8. Deception and Manipulation: The Arms of Leishmania, a Successful Parasite

    Science.gov (United States)

    Cecílio, Pedro; Pérez-Cabezas, Begoña; Santarém, Nuno; Maciel, Joana; Rodrigues, Vasco; Cordeiro da Silva, Anabela

    2014-01-01

    Leishmania spp. are intracellular parasitic protozoa responsible for a group of neglected tropical diseases, endemic in 98 countries around the world, called leishmaniasis. These parasites have a complex digenetic life cycle requiring a susceptible vertebrate host and a permissive insect vector, which allow their transmission. The clinical manifestations associated with leishmaniasis depend on complex interactions between the parasite and the host immune system. Consequently, leishmaniasis can be manifested as a self-healing cutaneous affliction or a visceral pathology, being the last one fatal in 85–90% of untreated cases. As a result of a long host–parasite co-evolutionary process, Leishmania spp. developed different immunomodulatory strategies that are essential for the establishment of infection. Only through deception and manipulation of the immune system, Leishmania spp. can complete its life cycle and survive. The understanding of the mechanisms associated with immune evasion and disease progression is essential for the development of novel therapies and vaccine approaches. Here, we revise how the parasite manipulates cell death and immune responses to survive and thrive in the shadow of the immune system. PMID:25368612

  9. Deception and Manipulation: the arms of Leishmania, a successful parasite

    Directory of Open Access Journals (Sweden)

    Pedro eCecílio

    2014-10-01

    Full Text Available Leishmania spp. are intracellular parasitic protozoa responsible for a group of neglected tropical diseases, endemic in 98 countries around the world, called leishmaniasis. These parasites have a complex digenetic life cycle requiring a susceptible vertebrate host and a permissive insect vector, which allow their transmission. The clinical manifestations associated with leishmaniasis depend on complex interactions between the parasite and the host immune system. Consequently, leishmaniasis can be manifested as a self-healing cutaneous affliction or a visceral pathology, being the last one fatal in 85-90% of untreated cases. As a result of a long host-parasite co-evolutionary process, Leishmania spp. developed different immunomodulatory strategies that are essential for the establishment of infection. Only through deception and manipulation of the immune system, Leishmania spp. can complete its life cycle and survive. The understanding of the mechanisms associated with immune evasion and disease progression is essential for the development of novel therapies and vaccine approaches. Here, we revise how the parasite manipulates cell death and immune responses to survive and thrive in the shadow of the immune system.

  10. An interfacially plasticized electro-responsive hydrogel for transdermal electro-activated and modulated (TEAM) drug delivery

    NARCIS (Netherlands)

    Indermun, S.; Choonara, Y.E.; Kumar, Pradeep; Toit, Du L.C.; Modi, G.; Luttge, R.; Pillay, V.

    2014-01-01

    This paper highlights the use of hydrogels in controlled drug delivery, and their application in stimuli responsive, especially electro-responsive, drug release. electro-conductive hydrogels (ECHs) displaying electro-responsive drug release were synthesized from semi-interpenetrating networks

  11. End-Effector Position Analysis Using Forward Kinematics For 5 Dof Pravak Robot Arm

    Directory of Open Access Journals (Sweden)

    Jolly Atit Shah

    2013-03-01

    Full Text Available Automatic control of the robotic manipulator involves study of kinematics and dynamics as a major issue. This paper involves the kinematic analysis of a Pravak Robot arm which is used for doing successful robotic manipulation task in its workspace. The Pravak Robot Arm is a 5-DOF robot having all the joints revolute. The kinematics problem is defined as the transformation from the Cartesian space to the joint space and vice versa. In this study the Denavit- Hartenberg (D-H model is used to model robot links and joints. Pravak Robot Arm is a simple and safe robotic system designed for laboratory training and research applications. This robot allows to gain theoretical and practical experience in robotics, automation and control systems. The MATLAB R2007 is used to analyse end effectors position for a set of joint parameter.

  12. Sol-Gel Material-Enabled Electro-Optic Polymer Modulators

    Science.gov (United States)

    Himmelhuber, Roland; Norwood, Robert A.; Enami, Yasufumi; Peyghambarian, Nasser

    2015-01-01

    Sol-gels are an important material class, as they provide easy modification of material properties, good processability and are easy to synthesize. In general, an electro-optic (EO) modulator transforms an electrical signal into an optical signal. The incoming electrical signal is most commonly information encoded in a voltage change. This voltage change is then transformed into either a phase change or an intensity change in the light signal. The less voltage needed to drive the modulator and the lower the optical loss, the higher the link gain and, therefore, the better the performance of the modulator. In this review, we will show how sol-gels can be used to enhance the performance of electro-optic modulators by allowing for designs with low optical loss, increased poling efficiency and manipulation of the electric field used for driving the modulator. The optical loss is influenced by the propagation loss in the device, as well as the losses occurring during fiber coupling in and out of the device. In both cases, the use of sol-gel materials can be beneficial due to the wide range of available refractive indices and low optical attenuation. The influence of material properties and synthesis conditions on the device performance will be discussed. PMID:26225971

  13. CONTROL SYSTEM FOR UNMANNED AIRCRAFT EQUIPPED WITH ROBOTICS ARM

    Directory of Open Access Journals (Sweden)

    Alexei A. Margun

    2014-11-01

    Full Text Available The paper deals with the problem of control system synthesis for multi rotational UAV equipped with robotics arm. Control algorithm is proposed based on the method of feedback linearization and synthesis of proportional-differential controller with the real time computation of the inertia tensor and center of mass changes and compensation of the reactive torque generated by the dynamics of the manipulator. Quadrocopter with attached articulated manipulator is selected as a model of the control object. Systems of equations describing the behavior of considered dynamical system are obtained according to the Newton and Euler-Lagrange laws. Expressions are offered, defining the inertia tensor and the position of the system center of mass depending on the current position of the manipulator, and the torque acting on the quadrocopter from the manipulator. Feedback linearization with arm influence compensation on quadrocopter is applied for the resulting nonlinear coupled system. As a result, robot dynamics equations have been converted to a linear stationary system. Converted system control is achieved by a proportional-differential controller. Examined system simulation is done with control method described in the paper and the classical method based on a proportional-differential controller. Simulation results confirm the effectiveness of the proposed approach and demonstrate that the proposed approach provides higher accuracy of the tracking error, than control method by means of proportional-differential regulator.

  14. An octopus-bioinspired solution to movement and manipulation for soft robots

    Energy Technology Data Exchange (ETDEWEB)

    Calisti, M; Giorelli, M; Laschi, C; Dario, P [BioRobotics Institute, Scuola Superiore Sant' Anna, Pisa (Italy); Levy, G; Hochner, B [Hebrew University of Jerusalem, Jerusalem (Israel); Mazzolai, B, E-mail: marcello.calisti@sssup.it, E-mail: michele.giorelli@sssup.it, E-mail: guy.levy@mail.huji.ac.il, E-mail: barbara.mazzolai@iit.it, E-mail: Binyamin.Hochner@huji.ac.il, E-mail: cecilia.laschi@sssup.it, E-mail: paolo.dario@sssup.it [Centre for Micro-BioRobotics-SSSA, Istituto Italiano di Tecnologia, Pontedera (Italy)

    2011-09-15

    Soft robotics is a challenging and promising branch of robotics. It can drive significant improvements across various fields of traditional robotics, and contribute solutions to basic problems such as locomotion and manipulation in unstructured environments. A challenging task for soft robotics is to build and control soft robots able to exert effective forces. In recent years, biology has inspired several solutions to such complex problems. This study aims at investigating the smart solution that the Octopus vulgaris adopts to perform a crawling movement, with the same limbs used for grasping and manipulation. An ad hoc robot was designed and built taking as a reference a biological hypothesis on crawling. A silicone arm with cables embedded to replicate the functionality of the arm muscles of the octopus was built. This novel arm is capable of pushing-based locomotion and object grasping, mimicking the movements that octopuses adopt when crawling. The results support the biological observations and clearly show a suitable way to build a more complex soft robot that, with minimum control, can perform diverse tasks.

  15. An octopus-bioinspired solution to movement and manipulation for soft robots

    International Nuclear Information System (INIS)

    Calisti, M; Giorelli, M; Laschi, C; Dario, P; Levy, G; Hochner, B; Mazzolai, B

    2011-01-01

    Soft robotics is a challenging and promising branch of robotics. It can drive significant improvements across various fields of traditional robotics, and contribute solutions to basic problems such as locomotion and manipulation in unstructured environments. A challenging task for soft robotics is to build and control soft robots able to exert effective forces. In recent years, biology has inspired several solutions to such complex problems. This study aims at investigating the smart solution that the Octopus vulgaris adopts to perform a crawling movement, with the same limbs used for grasping and manipulation. An ad hoc robot was designed and built taking as a reference a biological hypothesis on crawling. A silicone arm with cables embedded to replicate the functionality of the arm muscles of the octopus was built. This novel arm is capable of pushing-based locomotion and object grasping, mimicking the movements that octopuses adopt when crawling. The results support the biological observations and clearly show a suitable way to build a more complex soft robot that, with minimum control, can perform diverse tasks.

  16. An octopus-bioinspired solution to movement and manipulation for soft robots.

    Science.gov (United States)

    Calisti, M; Giorelli, M; Levy, G; Mazzolai, B; Hochner, B; Laschi, C; Dario, P

    2011-09-01

    Soft robotics is a challenging and promising branch of robotics. It can drive significant improvements across various fields of traditional robotics, and contribute solutions to basic problems such as locomotion and manipulation in unstructured environments. A challenging task for soft robotics is to build and control soft robots able to exert effective forces. In recent years, biology has inspired several solutions to such complex problems. This study aims at investigating the smart solution that the Octopus vulgaris adopts to perform a crawling movement, with the same limbs used for grasping and manipulation. An ad hoc robot was designed and built taking as a reference a biological hypothesis on crawling. A silicone arm with cables embedded to replicate the functionality of the arm muscles of the octopus was built. This novel arm is capable of pushing-based locomotion and object grasping, mimicking the movements that octopuses adopt when crawling. The results support the biological observations and clearly show a suitable way to build a more complex soft robot that, with minimum control, can perform diverse tasks.

  17. Design, modeling and control of a pneumatically actuated manipulator inspired by biological continuum structures

    International Nuclear Information System (INIS)

    Kang, Rongjie; Zheng Tianjiang; Guglielmino, Emanuele; Caldwell, Darwin G; Branson, David T

    2013-01-01

    Biological tentacles, such as octopus arms, have entirely flexible structures and virtually infinite degrees of freedom (DOF) that allow for elongation, shortening and bending at any point along the arm length. The amazing dexterity of biological tentacles has driven the growing implementation of continuum manipulators in robotic systems. This paper presents a pneumatic manipulator inspired by biological continuum structures in some of their key features and functions, such as continuum morphology, intrinsic compliance and stereotyped motions with hyper redundant DOF. The kinematics and dynamics of the manipulator are formulated and identified, and a hierarchical controller taking inspiration from the structure of an octopus nervous system is used to relate desired stereotyped motions to individual actuator inputs. Simulations and experiments are carried out to validate the model and prototype where good agreement was found between the two. (paper)

  18. Polymer micro-grippers with an integrated force sensor for biological manipulation

    International Nuclear Information System (INIS)

    Mackay, R E; Le, H R; Clark, S; Williams, J A

    2013-01-01

    The development of a novel micro-system integrating SU-8 polymer micro-grippers with a tensile force sensor for handling and characterizing the mechanical properties of delicate biological materials, such as fibrils, is presented. The micro-grippers are actuated by the electro-thermal effect and have gripping forces comparable to the common ‘hot-and-cold-arm’ grippers. A robust finite element model was developed to investigate system performance and validated experimentally. A new micro-mechanical calibration method using a piezoelectric manipulator with a micro-force measurement system was successfully applied to test the structure. Both FEA simulation and micro-mechanical testing results indicated that the system could fulfil the requirements for micro-object manipulation within a biological environment. (paper)

  19. Alterações morfológicas causadas pela reaplicação de ondas de choque eletro-hidráulicas, no rim de ratos Morphologic alterations caused by electro-hydraulic shock waves reapplication in rat kidney

    Directory of Open Access Journals (Sweden)

    Juliano José Jorge

    2002-03-01

    Full Text Available A recidiva de cálculos urinários é freqüente, necessitando múltiplas aplicações de ondas de choque para seu tratamento. O objetivo deste trabalho é pesquisar alterações morfológicas agudas ocorridas nos rins de ratos submetidos a reaplicação de ondas de choque. Foram utilizados 48 ratos, distribuídos em 4 grupos de 12 animais. O grupo I recebeu duas aplicações de 2000 ondas de choque, com 14 KV de intensidade em intervalo de 14 dias entre as aplicações. O grupo II serviu de controle. O grupo III recebeu apenas uma aplicação. O grupo IV serviu de controle. Os rins foram examinados após 72 horas da aplicação das ondas de choque, observando: hemorragias subcapsular, intersticial e glomerular; perda da junção corticomedular; infiltrado crônico; necrose cortical e edema perivascular. Os resultados mostraram que a reaplicação de ondas de choque eletro-hidráulicas sobre rins de ratos não causou maiores danos que os produzidos pela primeira aplicação.Urinary calculus recidives are frequents, needing shock waves multiple applications for its treatment. This research studies acute morphological changes that occur in the kidneys of rats subjected to electro-hydraulic shock waves reapplication. The experiment used 48 rats, divided in four groups of 12. The first group received two 2,000 shock waves applications with 14 kV intensity and a fourteen-day interval between the applications. The third group received only one 2,000 shock waves application of the same intensity. The second and fourth groups were control groups. The kidneys were examined 72 hours after the application, observing: subcapsular, interstitial and glomerular hemorrhage; corticol results showed that electro-hydraulic shock reapplication in the rat kidneys didn’t greater damages than the first application.

  20. Commander manipulator scoops prestigious mulit-million pound BNFL contract

    International Nuclear Information System (INIS)

    Bailey, Andrew.

    1997-01-01

    Twenty-one Commander robotic arms are on order from INBIS (formerly Ricardo Hitec) and BNFL Engineering Limited (''BEL'', the engineering arm of parent company BNFL). The multi-million pound contract was won amid fierce competition from other well-known names in robotic engineering. The specially designed Commander manipulators will be engaged in remotely handling Intermediate Level Waste (ILW) in a suite of four BNFL ILW plants, which are currently either under construction or planned at Sellafield. The first Commander will delivered to BNFL's Sellafield Silo Emptying Project in January 1998. (Author)

  1. Robot training of upper limb in multiple sclerosis: comparing protocols with or without manipulative task components.

    Science.gov (United States)

    Carpinella, Ilaria; Cattaneo, Davide; Bertoni, Rita; Ferrarin, Maurizio

    2012-05-01

    In this pilot study, we compared two protocols for robot-based rehabilitation of upper limb in multiple sclerosis (MS): a protocol involving reaching tasks (RT) requiring arm transport only and a protocol requiring both objects' reaching and manipulation (RMT). Twenty-two MS subjects were assigned to RT or RMT group. Both protocols consisted of eight sessions. During RT training, subjects moved the handle of a planar robotic manipulandum toward circular targets displayed on a screen. RMT protocol required patients to reach and manipulate real objects, by moving the robotic arm equipped with a handle which left the hand free for distal tasks. In both trainings, the robot generated resistive and perturbing forces. Subjects were evaluated with clinical and instrumental tests. The results confirmed that MS patients maintained the ability to adapt to the robot-generated forces and that the rate of motor learning increased across sessions. Robot-therapy significantly reduced arm tremor and improved arm kinematics and functional ability. Compared to RT, RMT protocol induced a significantly larger improvement in movements involving grasp (improvement in Grasp ARAT sub-score: RMT 77.4%, RT 29.5%, p=0.035) but not precision grip. Future studies are needed to evaluate if longer trainings and the use of robotic handles would significantly improve also fine manipulation.

  2. Advanced manipulator system for large hot cells

    International Nuclear Information System (INIS)

    Vertut, J.; Moreau, C.; Brossard, J.P.

    1981-01-01

    Large hot cells can be approached as extrapolated from smaller ones as wide, higher or longer in size with the same concept of using mechanical master slave manipulators and high density windows. This concept leads to a large number of working places and corresponding equipments, with a number of penetrations through the biological protection. When the large cell does not need a permanent operation of number of work places, as in particular to serve PIE machines and maintain the facility, use of servo manipulators with a large supporting unit and extensive use of television appears optimal. The advance on MA 23 and supports will be described including the extra facilities related to manipulators introduction and maintenance. The possibility to combine a powered manipulator and MA 23 (single or pair) on the same boom crane system will be described. An advance control system to bring the minimal dead time to control support movement, associated to the master slave arm operation is under development. The general television system includes over view cameras, associated with the limited number of windows, and manipulators camera. A special new system will be described which brings an automatic control of manipulator cameras and saves operator load and dead time. Full scale tests with MA 23 and support will be discussed. (author)

  3. Dual arm master controller development

    Science.gov (United States)

    Kuban, D. P.; Perkins, G. S.

    1985-01-01

    The advanced servomanipulator (ASM) slave was designed with an anthropomorphic stance gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape driven manipulators. Studies were performed which addressed to human factor design and performance tradeoffs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented.

  4. Efficient inverse position transformation for TR 4000S robot manipulator

    Directory of Open Access Journals (Sweden)

    Kesheng Wang

    1989-04-01

    Full Text Available An efficient method is developed for computing the inverse kinematic position solution with a closed form for the TR 4000S spray painting robot manipulator with five degrees of freedom and non-spherical wrist construction. The inverse kinematic problem is defined as the transformation from Cartesian space to the joint space. The solution is based on the geometrical separation of the arm and wrist of a robot manipulator and shows that it is very systematic, efficient and easily derived.

  5. A study on reliability of electro-hydraulic governor control system for large steam turbine in power plant

    International Nuclear Information System (INIS)

    Kang, Gu Hwa; Lee, Tae Hoon; Moon, Seung Jae; Lee, Jae Heon; Yoo, Ho Seon

    2008-01-01

    In this work, the right management procedure for hydraulic power oil will be discussed and suggested. A thermal power plant turbine should respond to the change of load status. However, to satisfy the frequency of alternating current, the revolution per minute should be kept constant. Therefore, by controlling the flow rate of the steam to the turbine, the governor satisfies the load variation without alternating the revolution per minutes of the turbine. To protect the governor, the hydraulic power unit should be managed carefully by controlling the quality and the flow rate of the oil

  6. Low-Inertia STEM Arm (LISA) Manipulators for Assistive Free-Flyers, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Altius Space Machines proposes the development of lightweight robotic manipulators, that utilize rollable composite STEM booms to provide a prismatic...

  7. Influence of temperature and hydraulic conductivity of soil on electrokinetic decontamination

    International Nuclear Information System (INIS)

    Kim, Gye-Nam; Kim, Seung-Soo; Jeong, Jung-Whan; Choi, Jong-Won

    2016-01-01

    The electrokinetic process holds great promise for the decontamination of contaminated soil because it has a high removal efficiency and is time-effective for low permeability. Electrokinetic decontamination can be used to treat soil contaminated with inorganic species and radionuclides. The main mechanisms of a contaminant's movement in an electrical field involved in electrokinetic technology are the electro-migration of the ionic species and electro-osmosis. Electro-migration probably contributes significantly to the removal of contaminants, especially at high concentrations of ionic contaminants and/or a high hydraulic permeability of soil. The cathode reaction should be depolarized to avoid the generation of hydroxides and their transport in soil. The selected liquid, also known as a purging reagent, should induce favorable pH conditions in soil, and/or interact with the incorporated heavy metals so that these heavy metals are removed from the soil. The removal efficiencies of uranium from contaminated soil in manufactured laboratory electrokinetic decontamination equipment were proportional to the elapsed time. The removal efficiencies of uranium for 2 days were 77-87%. In addition, the removal efficiencies according to the elapsed time after 2 days were reduced. When 75, 80, and 85℃ electrolyte temperatures in the cathode chamber were applied, the time required for the removal efficiency of uranium to reach 92% was 6, 5 and 4 days

  8. Influence of temperature and hydraulic conductivity of soil on electrokinetic decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Gye-Nam; Kim, Seung-Soo; Jeong, Jung-Whan; Choi, Jong-Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    The electrokinetic process holds great promise for the decontamination of contaminated soil because it has a high removal efficiency and is time-effective for low permeability. Electrokinetic decontamination can be used to treat soil contaminated with inorganic species and radionuclides. The main mechanisms of a contaminant's movement in an electrical field involved in electrokinetic technology are the electro-migration of the ionic species and electro-osmosis. Electro-migration probably contributes significantly to the removal of contaminants, especially at high concentrations of ionic contaminants and/or a high hydraulic permeability of soil. The cathode reaction should be depolarized to avoid the generation of hydroxides and their transport in soil. The selected liquid, also known as a purging reagent, should induce favorable pH conditions in soil, and/or interact with the incorporated heavy metals so that these heavy metals are removed from the soil. The removal efficiencies of uranium from contaminated soil in manufactured laboratory electrokinetic decontamination equipment were proportional to the elapsed time. The removal efficiencies of uranium for 2 days were 77-87%. In addition, the removal efficiencies according to the elapsed time after 2 days were reduced. When 75, 80, and 85℃ electrolyte temperatures in the cathode chamber were applied, the time required for the removal efficiency of uranium to reach 92% was 6, 5 and 4 days.

  9. Enhanced methanol electro-oxidation reaction on Pt-CoOx/MWCNTs hybrid electro-catalyst

    International Nuclear Information System (INIS)

    Nouralishahi, Amideddin; Rashidi, Ali Morad; Mortazavi, Yadollah; Khodadadi, Abbas Ali; Choolaei, Mohammadmehdi

    2015-01-01

    Highlights: • Promoting effects of Cobalt oxide on methanol electro-oxidation over Pt/MWCNTs are investigated. • Higher activity, about 2.9 times, and enhanced stability are observed on Pt-CoO x /MWCNTs. • Electrochemical active surface area of Pt nanoparticles is significantly improved upon CoO x addition. • Bi-functional mechanism is facilitated in presence of CoO x . - Abstract: The electro-catalytic behavior of Pt-CoO x /MWCNTs in methanol electro-oxidation reaction (MOR) is investigated and compared to that of Pt/MWCNTs. The electro-catalysts were synthesized by an impregnation method using NaBH 4  as the reducing agent. The morphological and physical characteristics of samples are examined by XRD, TEM, ICP and EDS techniques. In the presence of CoO x , Pt nanoparticles were highly distributed on the support with an average particle size of 2 nm, an obvious decrease from 5.1 nm for Pt/MWCNTs. Cyclic voltammetry, CO-stripping, Chronoamperometry, and electrochemical impedance spectroscopy (EIS) measurements are used to study the electrochemical behavior of the electro-catalysts. The results revealed a considerable enhancement in the oxidation kinetics of CO ads on Pt active sites by the participation of CoO x . Compared to Pt/MWCNTs, Pt-CoO x /MWCNTs sample has a larger electrochemical active surface area (ECSA) and higher electro-catalytic activity and stability toward methanol electro-oxidation. According to the results of cyclic voltammetry, the forward anodic peak current density enhances more than 89% at the optimum atomic ratio of Pt:Co = 2:1. Furthermore, inclusion of cobalt oxide species causes the onset potential of methanol electro-oxidation reaction to shift 84 mV to negative values compared to that on Pt/MWCNTs. Based on EIS data, dehydrogenation of methanol is the rate-determining step of MOR on both Pt/MWCNTs and Pt-CoO x /MWCNTs, at small overpotentials. However, at higher overpotentials, the oxidation of adsorbed oxygen-containing groups

  10. Electro-optic routing of photons from a single quantum dot in photonic integrated circuits

    Science.gov (United States)

    Midolo, Leonardo; Hansen, Sofie L.; Zhang, Weili; Papon, Camille; Schott, Rüdiger; Ludwig, Arne; Wieck, Andreas D.; Lodahl, Peter; Stobbe, Søren

    2017-12-01

    Recent breakthroughs in solid-state photonic quantum technologies enable generating and detecting single photons with near-unity efficiency as required for a range of photonic quantum technologies. The lack of methods to simultaneously generate and control photons within the same chip, however, has formed a main obstacle to achieving efficient multi-qubit gates and to harness the advantages of chip-scale quantum photonics. Here we propose and demonstrate an integrated voltage-controlled phase shifter based on the electro-optic effect in suspended photonic waveguides with embedded quantum emitters. The phase control allows building a compact Mach-Zehnder interferometer with two orthogonal arms, taking advantage of the anisotropic electro-optic response in gallium arsenide. Photons emitted by single self-assembled quantum dots can be actively routed into the two outputs of the interferometer. These results, together with the observed sub-microsecond response time, constitute a significant step towards chip-scale single-photon-source de-multiplexing, fiber-loop boson sampling, and linear optical quantum computing.

  11. Dynamic whole-body robotic manipulation

    Science.gov (United States)

    Abe, Yeuhi; Stephens, Benjamin; Murphy, Michael P.; Rizzi, Alfred A.

    2013-05-01

    The creation of dynamic manipulation behaviors for high degree of freedom, mobile robots will allow them to accomplish increasingly difficult tasks in the field. We are investigating how the coordinated use of the body, legs, and integrated manipulator, on a mobile robot, can improve the strength, velocity, and workspace when handling heavy objects. We envision that such a capability would aid in a search and rescue scenario when clearing obstacles from a path or searching a rubble pile quickly. Manipulating heavy objects is especially challenging because the dynamic forces are high and a legged system must coordinate all its degrees of freedom to accomplish tasks while maintaining balance. To accomplish these types of manipulation tasks, we use trajectory optimization techniques to generate feasible open-loop behaviors for our 28 dof quadruped robot (BigDog) by planning trajectories in a 13 dimensional space. We apply the Covariance Matrix Adaptation (CMA) algorithm to solve for trajectories that optimize task performance while also obeying important constraints such as torque and velocity limits, kinematic limits, and center of pressure location. These open-loop behaviors are then used to generate desired feed-forward body forces and foot step locations, which enable tracking on the robot. Some hardware results for cinderblock throwing are demonstrated on the BigDog quadruped platform augmented with a human-arm-like manipulator. The results are analogous to how a human athlete maximizes distance in the discus event by performing a precise sequence of choreographed steps.

  12. Multi-control modes for a master-slave manipulator with different configurations and its maneuverability

    International Nuclear Information System (INIS)

    Matsuhira, Nobuto; Asakura, Makoto; Bamba, Hiroyuki

    1995-01-01

    The new master-slave control method is proposed on multi-control modes for a master-slave manipulator with different configurations. A virtual internal model following control is applied to position symmetrical bilateral control. In our method, a master-slave control mode (MS-mode), a joystick control mode (JS-mode), a master arm offset mode (OM-mode), and a servo hold mode (LK-mode) are able to be realized by operating the desired output values of the virtual internal models in a common control algorithm. There is compliant characteristic between the master and slave models. In the result of evaluation experiments between the MS-mode and the JS-mode, although the MS-mode is superior to the JS-mode in manipulating a fine task, our JS-mode is found to be useful to carry out such a task compared with a conventional JS-mode which only directs the rates for the slave arm. In the JS-mode, the slave arm moves to the position where the reaction force of the slave arm and the operating force of the master arm are balanced. Thus, it is possible either to control an overload for an object and to control the contact force. The validity of the proposed method is verified. (author)

  13. Optimal trajectory generation for mechanical arms. M.S. Thesis

    Science.gov (United States)

    Iemenschot, J. A.

    1972-01-01

    A general method of generating optimal trajectories between an initial and a final position of an n degree of freedom manipulator arm with nonlinear equations of motion is proposed. The method is based on the assumption that the time history of each of the coordinates can be expanded in a series of simple time functions. By searching over the coefficients of the terms in the expansion, trajectories which minimize the value of a given cost function can be obtained. The method has been applied to a planar three degree of freedom arm.

  14. Comparison of Methods for Modeling a Hydraulic Loader Crane With Flexible Translational Links

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen; Andersen, Torben O.; Nielsen, Brian K.

    2015-01-01

    not hold for translational links. Hence, special care has to be taken when including flexible translational links. In the current paper, different methods for modeling a hydraulic loader crane with a telescopic arm are investigated and compared using both the finite segment (FS) and AMs method...

  15. Dynamic Characteristics of Communication Lines with Distributed Parameters to Control the Throttle-controlled Hydraulic Actuators

    Directory of Open Access Journals (Sweden)

    D. N. Popov

    2015-01-01

    Full Text Available The article considers a mathematical model of the hydraulic line for remote control of electro-hydraulic servo drive (EHSD with throttle control. This type of hydraulic lines is designed as a backup to replace the electrical connections, which are used to control EHSD being remote from the site with devices located to form the control signals of any object. A disadvantage of electric connections is that they are sensitive to magnetic fields and thereby do not provide the required reliability of the remote control. Hydraulic lines have no this disadvantage and therefore are used in aircraft and other industrial systems. However, dynamic characteristics of hydraulic systems still have been investigated insufficiently in the case of transmitting control signals at a distance at which the signal may be distorted when emerging the wave processes.The article results of mathematical simulation, which are verified through physical experimentation, largely eliminate the shortcomings of said information.The mathematical model described in the paper is based on the theory of unsteady pressure compressible fluids. In the model there are formulas that provide calculation of frequency characteristics of the hydraulic lines under hydraulic oscillations of the laminar flow parameters of viscous fluid.A real mock-up of the system under consideration and an experimental ad hoc unit are used to verify the results of mathematically simulated hydraulic systems.Calculated logarithmic amplitude and phase frequency characteristics compared with those obtained experimentally prove, under certain conditions, the proposed theoretical method of calculation. These conditions have to ensure compliance with initial parameters of fluid defined under stationary conditions. The applied theory takes into consideration a non-stationary hydraulic resistance of the line when calculating frequency characteristics.The scientific novelty in the article material is presented in

  16. On nonlinear thermo-electro-elasticity.

    Science.gov (United States)

    Mehnert, Markus; Hossain, Mokarram; Steinmann, Paul

    2016-06-01

    Electro-active polymers (EAPs) for large actuations are nowadays well-known and promising candidates for producing sensors, actuators and generators. In general, polymeric materials are sensitive to differential temperature histories. During experimental characterizations of EAPs under electro-mechanically coupled loads, it is difficult to maintain constant temperature not only because of an external differential temperature history but also because of the changes in internal temperature caused by the application of high electric loads. In this contribution, a thermo-electro-mechanically coupled constitutive framework is proposed based on the total energy approach. Departing from relevant laws of thermodynamics, thermodynamically consistent constitutive equations are formulated. To demonstrate the performance of the proposed thermo-electro-mechanically coupled framework, a frequently used non-homogeneous boundary-value problem, i.e. the extension and inflation of a cylindrical tube, is solved analytically. The results illustrate the influence of various thermo-electro-mechanical couplings.

  17. Sensor-based whole-arm obstacle avoidance for unstructured environments

    International Nuclear Information System (INIS)

    Wintenberg, AL.; Butler, P.L.; Babcock, S.M.; Ericson, M.N.; Britton, C.L. Jr.; Hamel, W.R.

    1992-01-01

    Whole-arm obstacle avoidance is needed for a variety of robotic applications in the Environmental Restoration and Waste Management (ER ampersand WM) Program. Typical industrial applications of robotics involve well-defined work spaces, allowing a predetermined knowledge of collision-free paths for manipulator motion. In the unstructured or poorly defined hazardous environments of the ER ampersand WM program, the potential for significant problems resulting from collisions between manipulators and the environment in which they are utilized is great. A sensing system under development, which will provide protection against such collisions, is described in this paper

  18. Electro-weak theory

    International Nuclear Information System (INIS)

    Deshpande, N.G.

    1980-01-01

    By electro-weak theory is meant the unified field theory that describes both weak and electro-magnetic interactions. The development of a unified electro-weak theory is certainly the most dramatic achievement in theoretical physics to occur in the second half of this century. It puts weak interactions on the same sound theoretical footing as quantum elecrodynamics. Many theorists have contributed to this development, which culminated in the works of Glashow, Weinberg and Salam, who were jointly awarded the 1979 Nobel Prize in physics. Some of the important ideas that contributed to this development are the theory of beta decay formulated by Fermi, Parity violation suggested by Lee and Yang, and incorporated into immensely successful V-A theory of weak interactions by Sudarshan and Marshak. At the same time ideas of gauge invariance were applied to weak interaction by Schwinger, Bludman and Glashow. Weinberg and Salam then went one step further and wrote a theory that is renormalizable, i.e., all higher order corrections are finite, no mean feat for a quantum field theory. The theory had to await the development of the quark model of hadrons for its completion. A description of the electro-weak theory is given

  19. Maximizing Use of Robot-Arm No. 3 in Da Vinci–Assisted Thoracic Surgery

    Science.gov (United States)

    Kajiwara, Naohiro; Maeda, Junichi; Yoshida, Koichi; Kato, Yasufumi; Hagiwara, Masaru; Kakihana, Masatoshi; Ohira, Tatsuo; Kawate, Norihiko; Ikeda, Norihiko

    2015-01-01

    We have previously reported on the importance of appropriate robot-arm settings and replacement of instrument ports in robot-assisted thoracic surgery, because the thoracic cavity requires a large space to access all lesions in various areas of the thoracic cavity from the apex to the diaphragm and mediastinum and the chest wall.1–3 Moreover, it can be difficult to manipulate the da Vinci Surgical System using only arms No. 1 and No. 2 depending on the tumor location. However, arm No. 3 is usually positioned on the same side as arm No. 2, and sometimes it is only used as an assisting-arm to avoid conflict with other arms (Fig. 1). In this report, we show how robot-arm No. 3 can be used with maximum effectiveness in da Vinci-assisted thoracic surgery. PMID:26011219

  20. Control and applications of cooperating disparate robotic manipulators relevant to nuclear waste management

    Science.gov (United States)

    Lew, Jae Young; Book, Wayne J.

    1991-01-01

    Remote handling in nuclear waste management requires a robotic system with precise motion as well as a large workspace. The concept of a small arm mounted on the end of a large arm may satisfy such needs. However, the performance of such a serial configuration lacks payload capacity which is a crucial factor for handling a massive object. Also, this configuration induces more flexibility on the structure. To overcome these problems, the topology of bracing the tip of the small arm (not the large arm) and having an end effector in the middle of the chain is proposed in this paper. Also, control of these cooperating disparate manipulators is accomplished in computer simulations. Thus, this robotic system can have the accuracy of the small arm, and at the same time, it can have the payload capacity and large workspace of the large arm.

  1. Displacement characteristics of a piezoactuator-based prototype microactuator with a hydraulic displacement amplification system

    Energy Technology Data Exchange (ETDEWEB)

    Muralidhara [NMAMIT, Nitte (India); Rao, Rathnamala [NITK, Surathkal (India)

    2015-11-15

    In this study, a new piezoactuator-based prototype microactuator is proposed with a hydraulic displacement amplification system. A piezoactuator is used to deflect a diaphragm which displaces a certain volume of hydraulic fluid into a smaller-diameter piston chamber, thereby amplifying the displacement at the other end of the piston. An electro-mechanical model is implemented to estimate the displacement of a multilayer piezoelectric actuator for the applied input voltage considering the hysteresis behavior. The displacement characteristics of the proposed microactuator are studied for triangular actuation voltage signal. Results of the experiments and simulation of the displacement behavior of the stacked piezoactuator and the amplified displacement of the prototype actuator were compared. Experimental results suggest that the mathematical model developed for the new piezoactuator-based prototype actuator is capable of estimating its displacement behavior accurately, within an error of 1.2%.

  2. Displacement characteristics of a piezoactuator-based prototype microactuator with a hydraulic displacement amplification system

    International Nuclear Information System (INIS)

    Muralidhara; Rao, Rathnamala

    2015-01-01

    In this study, a new piezoactuator-based prototype microactuator is proposed with a hydraulic displacement amplification system. A piezoactuator is used to deflect a diaphragm which displaces a certain volume of hydraulic fluid into a smaller-diameter piston chamber, thereby amplifying the displacement at the other end of the piston. An electro-mechanical model is implemented to estimate the displacement of a multilayer piezoelectric actuator for the applied input voltage considering the hysteresis behavior. The displacement characteristics of the proposed microactuator are studied for triangular actuation voltage signal. Results of the experiments and simulation of the displacement behavior of the stacked piezoactuator and the amplified displacement of the prototype actuator were compared. Experimental results suggest that the mathematical model developed for the new piezoactuator-based prototype actuator is capable of estimating its displacement behavior accurately, within an error of 1.2%.

  3. Dual arm master controller concept

    International Nuclear Information System (INIS)

    Kuban, D.P.; Perkins, G.S.

    1984-01-01

    The Advanced Servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented. 6 references, 3 figures

  4. Computer coordination of limb motion for locomotion of a multiple-armed robot for space assembly

    Science.gov (United States)

    Klein, C. A.; Patterson, M. R.

    1982-01-01

    Consideration is given to a possible robotic system for the construction of large space structures, which may be described as a multiple general purpose arm manipulator vehicle that can walk over the structure under construction to a given site for further work. A description is presented of the locomotion of such a vehicle, modeling its arms in terms of a currently available industrial manipulator. It is noted that for whatever maximum speed of operation is chosen, rapid changes in robot velocity create situations in which already-selected handholds are no longer practical. A step is added to the 'free gait' walking algorithm in order to solve this problem.

  5. Three types of planar structure microspring electro-thermal actuators with insulating beam constraints

    Science.gov (United States)

    Luo, J. K.; Flewitt, A. J.; Spearing, S. M.; Fleck, N. A.; Milne, W. I.

    2005-08-01

    A new concept of using an electrically insulating beam as a constraint is proposed to construct planar spring-like electro-thermal actuators with large displacements. On the basis of this concept, three types of microspring actuators with multi-chevron structures and constraint beams are introduced. The constraint beams in one type (the spring) of these devices are horizontally positioned to restrict the expansion of the active arms in the x-direction, and to produce a displacement in the y-direction only. In the other two types of actuators (the deflector and the contractor), the constraint beams are positioned parallel to the active arms. When the constraint beams are on the inner side of the active arms, the actuator produces an outward deflection in the y-direction. When they are on the outside of the active arms, the actuator produces an inward contraction. Finite-element analysis was used to model the performances. The simulation shows that the displacements of these microspring actuators are all proportional to the number of the chevron sections in series, thus achieving superior displacements to alternative actuators. The displacement of a spring actuator strongly depends on the beam angle, and decreases with increasing the beam angle, the deflector is insensitive to the beam angle, while the displacement of a contractor actuator increases with the beam angle.

  6. Virtual modeling of robot-assisted manipulations in abdominal surgery.

    Science.gov (United States)

    Berelavichus, Stanislav V; Karmazanovsky, Grigory G; Shirokov, Vadim S; Kubyshkin, Valeriy A; Kriger, Andrey G; Kondratyev, Evgeny V; Zakharova, Olga P

    2012-06-27

    To determine the effectiveness of using multidetector computed tomography (MDCT) data in preoperative planning of robot-assisted surgery. Fourteen patients indicated for surgery underwent MDCT using 64 and 256-slice MDCT. Before the examination, a specially constructed navigation net was placed on the patient's anterior abdominal wall. Processing of MDCT data was performed on a Brilliance Workspace 4 (Philips). Virtual vectors that imitate robotic and assistant ports were placed on the anterior abdominal wall of the 3D model of the patient, considering the individual anatomy of the patient and the technical capabilities of robotic arms. Sites for location of the ports were directed by projection on the roentgen-positive tags of the navigation net. There were no complications observed during surgery or in the post-operative period. We were able to reduce robotic arm interference during surgery. The surgical area was optimal for robotic and assistant manipulators without any need for reinstallation of the trocars. This method allows modeling of the main steps in robot-assisted intervention, optimizing operation of the manipulator and lowering the risk of injuries to internal organs.

  7. Development of a Control System for PRIDE Remote Servo-manipulator

    International Nuclear Information System (INIS)

    Lee, Jong Kwang; Park, Byung Suk; Lee, Hyo Jik; Kim, Kyung Tae; Kim, Sung Hyun; Park, Hee Sung; Kim, Young Hwan; Jung, Jae Hoo; Kim, Ki Ho; Kim, Ho Dong

    2009-12-01

    KAERI is developing the PRIDE(PyRoprocess Integrated inactive DEmonstration) facility to verify the integrated performance of full Pyroprocess flow. A main process cell in the PRIDE facility will be filled with argon gas which prohibits direct access by human operators. Therefore, all the operation and maintenance of the process equipment is performed remotely through a master-slave manipulation. This research focuses on the design, fabrication, and interface of a control system which integrates several hardware systems such as a dual arm master-slave servo-manipulator, a horizontally moving transporter for a master manipulator, a bridge transporter for a slave manipulator, a chain hoist, camera systems and their display system, a manual console, and a pendant, etc. Also, a bilateral force-reflection controller considering an elasticity and vibration modes of wire cable has been developed for master-slave remote manipulation. The results obtained in this study will be applied for the force-reflection control of the bridge-transported master-slave servo-manipulator system for use in the PRIDE facility. Since this research is an essential work in robotics related fields, the results would be widely used for developing power manipulators and process automation equipment

  8. Development of a Control System for PRIDE Remote Servo-manipulator

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Kwang; Park, Byung Suk; Lee, Hyo Jik; Kim, Kyung Tae; Kim, Sung Hyun; Park, Hee Sung; Kim, Young Hwan; Jung, Jae Hoo; Kim, Ki Ho; Kim, Ho Dong

    2009-12-15

    KAERI is developing the PRIDE(PyRoprocess Integrated inactive DEmonstration) facility to verify the integrated performance of full Pyroprocess flow. A main process cell in the PRIDE facility will be filled with argon gas which prohibits direct access by human operators. Therefore, all the operation and maintenance of the process equipment is performed remotely through a master-slave manipulation. This research focuses on the design, fabrication, and interface of a control system which integrates several hardware systems such as a dual arm master-slave servo-manipulator, a horizontally moving transporter for a master manipulator, a bridge transporter for a slave manipulator, a chain hoist, camera systems and their display system, a manual console, and a pendant, etc. Also, a bilateral force-reflection controller considering an elasticity and vibration modes of wire cable has been developed for master-slave remote manipulation. The results obtained in this study will be applied for the force-reflection control of the bridge-transported master-slave servo-manipulator system for use in the PRIDE facility. Since this research is an essential work in robotics related fields, the results would be widely used for developing power manipulators and process automation equipment.

  9. Magnetic Field and Torque Output of Packaged Hydraulic Torque Motor

    Directory of Open Access Journals (Sweden)

    Liang Yan

    2018-01-01

    Full Text Available Hydraulic torque motors are one key component in electro-hydraulic servo valves that convert the electrical signal into mechanical motions. The systematic characteristics analysis of the hydraulic torque motor has not been found in the previous research, including the distribution of the electromagnetic field and torque output, and particularly the relationship between them. In addition, conventional studies of hydraulic torque motors generally assume an evenly distributed magnetic flux field and ignore the influence of special mechanical geometry in the air gaps, which may compromise the accuracy of analyzing the result and the high-precision motion control performance. Therefore, the objective of this study is to conduct a detailed analysis of the distribution of the magnetic field and torque output; the influence of limiting holes in the air gaps is considered to improve the accuracy of both numerical computation and analytical modeling. The structure and working principle of the torque motor are presented first. The magnetic field distribution in the air gaps and the magnetic saturation in the iron blocks are analyzed by using a numerical approach. Subsequently, the torque generation with respect to the current input and assembly errors is analyzed in detail. This shows that the influence of limiting holes on the magnetic field is consistent with that on torque generation. Following this, a novel modified equivalent magnetic circuit is proposed to formulate the torque output of the hydraulic torque motor analytically. The comparison among the modified equivalent magnetic circuit, the conventional modeling approach and the numerical computation is conducted, and it is found that the proposed method helps to improve the modeling accuracy by taking into account the effect of special geometry inside the air gaps.

  10. RCV-150 remotely operated vehicle and its operation in the hostile undersea environment

    International Nuclear Information System (INIS)

    Billet, A.B.

    1984-01-01

    The past decade has shown a dramatic increase in the use of unmanned tethered vehicles in worldwide marine fields. These are used for inspection, debris removal and object retrieval. The RCV-150/sup chemical bond/ system is an example of these advanced technology vehicles. With the requirements of high maneuverability and unusual inspection a responsive, high performance, compact hydraulic system was developed. The hydraulic system is powered by an electric motor-driven pump which provides hydraulic power to the four thruster motors and to the five-function manipulator work arm

  11. Control of free-flying space robot manipulator systems

    Science.gov (United States)

    Cannon, Robert H., Jr.

    1989-01-01

    Control techniques for self-contained, autonomous free-flying space robots are being tested and developed. Free-flying space robots are envisioned as a key element of any successful long term presence in space. These robots must be capable of performing the assembly, maintenance, and inspection, and repair tasks that currently require astronaut extra-vehicular activity (EVA). Use of robots will provide economic savings as well as improved astronaut safety by reducing and in many cases, eliminating the need for human EVA. The focus of the work is to develop and carry out a set of research projects using laboratory models of satellite robots. These devices use air-cushion-vehicle (ACV) technology to simulate in two dimensions the drag-free, zero-g conditions of space. Current work is divided into six major projects or research areas. Fixed-base cooperative manipulation work represents our initial entry into multiple arm cooperation and high-level control with a sophisticated user interface. The floating-base cooperative manipulation project strives to transfer some of the technologies developed in the fixed-base work onto a floating base. The global control and navigation experiment seeks to demonstrate simultaneous control of the robot manipulators and the robot base position so that tasks can be accomplished while the base is undergoing a controlled motion. The multiple-vehicle cooperation project's goal is to demonstrate multiple free-floating robots working in teams to carry out tasks too difficult or complex for a single robot to perform. The Location Enhancement Arm Push-off (LEAP) activity's goal is to provide a viable alternative to expendable gas thrusters for vehicle propulsion wherein the robot uses its manipulators to throw itself from place to place. Because the successful execution of the LEAP technique requires an accurate model of the robot and payload mass properties, it was deemed an attractive testbed for adaptive control technology.

  12. Hydraulically amplified self-healing electrostatic actuators with muscle-like performance

    Science.gov (United States)

    Acome, E.; Mitchell, S. K.; Morrissey, T. G.; Emmett, M. B.; Benjamin, C.; King, M.; Radakovitz, M.; Keplinger, C.

    2018-01-01

    Existing soft actuators have persistent challenges that restrain the potential of soft robotics, highlighting a need for soft transducers that are powerful, high-speed, efficient, and robust. We describe a class of soft actuators, termed hydraulically amplified self-healing electrostatic (HASEL) actuators, which harness a mechanism that couples electrostatic and hydraulic forces to achieve a variety of actuation modes. We introduce prototypical designs of HASEL actuators and demonstrate their robust, muscle-like performance as well as their ability to repeatedly self-heal after dielectric breakdown—all using widely available materials and common fabrication techniques. A soft gripper handling delicate objects and a self-sensing artificial muscle powering a robotic arm illustrate the wide potential of HASEL actuators for next-generation soft robotic devices.

  13. Electro-optic transceivers for terahertz-wave applications

    International Nuclear Information System (INIS)

    Chen, Q.; Tani, M.; Jiang, Zhiping; Zhang, X.-C.

    2001-01-01

    Because of the reciprocal behavior of the optical rectification and the electro-optic effect in a nonlinear optical crystal, an electro-optic transceiver can alternately transmit pulsed electromagnetic radiation (optical rectification) and detect the return signal (electro-optic effect) in the same crystal. However, the optimal condition of the electro-optic transceiver may be very different from that of the spatially separated emitter and receiver. We present a detailed description of the crystal-orientation dependence of the electro-optic terahertz devices (transmitter, receiver, and transceiver). It is found that for a (110) zinc-blende electro-optical crystal, the efficiency of the electro-optic transceiver will be optimized when the angle between the polarization of the optical pump beam and the crystallographic z axis [0,0,1] is 26 degree. Meanwhile, for a (111) crystal, the angle between the optical beam and the crystallographic direction [-1,-1,2] should be 23 degree. The experimental results from a (110) ZnTe transceiver verify theoretical calculations and demonstrate a direct way to optimize the working efficiency of an electro-optic terahertz transceiver. [copyright] 2001 Optical Society of America

  14. Electro-optic diffraction grating tuned laser

    International Nuclear Information System (INIS)

    Hughes, R.S.

    1975-01-01

    An electro-optic diffraction grating tuned laser comprising a laser medium, output mirror, retro-reflective grating and an electro-optic diffraction grating beam deflector positioned between the laser medium and the reflective diffraction grating is described. An optional angle multiplier may be used between the electro-optic diffraction grating and the reflective grating. (auth)

  15. Non-classic multiscale modeling of manipulation based on AFM, in aqueous and humid ambient

    Science.gov (United States)

    Korayem, M. H.; Homayooni, A.; Hefzabad, R. N.

    2018-05-01

    To achieve a precise manipulation, it is important that an accurate model consisting the size effect and environmental conditions be employed. In this paper, the non-classical multiscale modeling is developed to investigate the manipulation in a vacuum, aqueous and humid ambient. The manipulation structure is considered into two parts as a macro-field (MF) and a nano-field (NF). The governing equations of the AFM components (consist of the cantilever and tip) in the MF are derived based on the modified couple stress theory. The material length scale parameter is used to study the size effect. The fluid flow in the MF is assumed as the Couette and Creeping flows. Moreover, the NF is modeled using the molecular dynamics. The Electro-Based (ELBA) model is considered to model the ambient condition in the NF. The nanoparticle in the different conditions is taken into account to study the manipulation. The results of the manipulation indicate that the predicted deflection of the non-classical model is less than the classical one. Comparison of the nanoparticle travelled distance on substrate shows that the manipulation in the submerged condition is close to the ideal manipulation. The results of humid condition illustrate that by increasing the relative humidity (RH) the manipulation force decreases. Furthermore, Root Mean Square (RMS) as a criterion of damage demonstrates that the submerged nanoparticle has the minimum damage, however, the minimum manipulation force occurs in superlative humid ambient.

  16. Sensor-based whole-arm obstacle avoidance for unstructured environments

    International Nuclear Information System (INIS)

    Wintenberg, A.L.; Butler, P.L.; Babcock, S.M.; Ericson, M.N.; Armstrong, G.A.; Britton, C.L. Jr.; Hamel, W.R.

    1992-01-01

    Whole-arm obstacle avoidance is needed for a variety of robotic applications in the Environmental Restoration and Waste Management (ER ampersand WM) Program. Typical industrial applications of robotics involve well-defined workspaces, allowing a predetermined knowledge of collision-free paths for manipulator motion. However, many hazardous environments are unstructured or poorly defined, providing a significant potential for collisions between manipulators and the environment. In order to allow applications of robotics in such situations, a sensing system is under development which will provide protection against collisions. Specifics of this system including system architecture and projected implementation are described

  17. Hydraulic actuators for flexible robots : a flatness based approach for tracking and vibration control

    NARCIS (Netherlands)

    Wey, T.; Lemmen, M.; Bernzen, W.; Wey, T.

    1999-01-01

    This paper deals with an application of the differential algebraic flatness approach to hydraulic drives. Here, an elastic robot arm driven by a differential cylinder is investigated. The task is to design a suitable control law which not only tracks a given trajectory but also allows the damping of

  18. Fundamentals of electro-engineering I

    International Nuclear Information System (INIS)

    Rapsik, M.; Smola, M.; Bohac, M.; Mucha, M.

    2004-01-01

    This is the text-book of the fundamentals of electro-engineering. It contains the following chapters: (1) Selected terms in electro-engineering; (2) Fundamental electric values; (3) Energy and their transformations; (4) Water, hydro-energy and hydro-energetic potential of the Slovak Republic; (5) Nuclear power engineering; (6) Conventional thermal power plants; (7) Heating and cogeneration of electric power and heat production; (8) Equipment of electricity supply system; (9) Measurements in electro-engineering ; (10) Regulation of frequency and voltage, electric power quality

  19. Electro-optic polymers for high speed modulators

    NARCIS (Netherlands)

    Balakrishnan, M.; Diemeer, Mart; Driessen, A.; Faccini, M.; Verboom, Willem; Reinhoudt, David; Leinse, Arne; Megret, P.; Wuilpart, M.; Bette, S.; Staquet, N.

    2005-01-01

    Different electro-optic polymer systems are analyzed with respect to their electro-optic activity, glass transition temperature $(T_g)$ and photodefinable properties. The polymers tested are polysulfone (PS) and polycarbonate (PC). The electro-optic chromophore,

  20. Single-photon manipulation in Nanophotonic Circuits

    DEFF Research Database (Denmark)

    Hansen, Sofie Lindskov

    Quantum dots in photonic nanostructures has long been known to be a very powerful and versatile solid-state platform for conducting quantum optics experiments. The present PhD thesis describes experimental demonstrations of single-photon generation and subsequent manipulation all realized...... on a gallium arsenide platform. This platform offers near-unity coupling between embedded single-photon emitters and a photonic mode, as well as the ability to suppress decoherence mechanisms, making it highly suited for quantum information applications. In this thesis we show how a single-photon router can...... be realized on a chip with embedded quantum dots. This allows for on-chip generation and manipulation of single photons. The router consists of an on-chip interferometer where the phase difference between the arms of the interferometer is controlled electrically. The response time of the device...

  1. Design and fabrication of an articulated four axes microrobot arm

    Science.gov (United States)

    Zhang, Ruoshi; Yang, Zhong; Wei, Danming; Popa, Dan O.

    2017-05-01

    In order to carry out nanomanufacturing tasks, a microrobot requires both high precision and high reliability over prolonged periods of time. Articulated Four-Axis Microrobots (AFAM) have been introduced a decade ago as millimetric microrobots capable of carrying out nanoscale tasks. The original robot design relied on a Micro Electro Mechanical (MEMS) actuator bank positioned onto a Silicon substrate, and an assembled arm mechanically coupled to the actuators through a cable. Movement of two thermal actuator banks positions the AFAM's end effector in 3-Dimensional space with approximately 75 microns workspace and 50 nm repeatability. However, failure of the AFAM's cable mechanism was observed after less than 1 million cycles. In this paper, we propose a novel arm mechanism for AFAM that improve its performance. The design presented in this article substitutes the "wire-gluing" cable with an anchored electrostatic actuator, and therefore it simplifies assembly requirements, reduces overall footprint of the microrobot, and achieves higher operating frequency. Simulation results are presented for a rotary electrostatic comb drive as basis for the microrobot arm with overall dimensions of 2 mm × 2 mm. The AFAM arm cantilever is 1 mm long to achieve a workspace of dimension of 75 microns along the vertical axis. Experimental evaluation of the design was accomplished using a prototype fabricated on a silicon on insulator (SOI) wafer processed with the deep reactive ion etching (DRIE) process.

  2. Enhanced methanol electro-oxidation reaction on Pt-CoO{sub x}/MWCNTs hybrid electro-catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Nouralishahi, Amideddin, E-mail: Nouralishahi@ut.ac.ir [Catalysis and Nanostructured Materials Research Laboratory, School of Chemical Engineering, University of Tehran, P.O. Box 11155/4563, Tehran (Iran, Islamic Republic of); Caspian Faculty of Engineering, University of Tehran, P.O. Box 43841-119, Rezvanshahr (Iran, Islamic Republic of); Catalysis and Nanotechnology Research Division, Research Institute of Petroleum Industry (RIPI), P.O. Box 14665-1998, Tehran (Iran, Islamic Republic of); Rashidi, Ali Morad, E-mail: Rashidiam@ripi.ir [Catalysis and Nanotechnology Research Division, Research Institute of Petroleum Industry (RIPI), P.O. Box 14665-1998, Tehran (Iran, Islamic Republic of); Mortazavi, Yadollah, E-mail: Mortazav@ut.ac.ir [Catalysis and Nanostructured Materials Research Laboratory, School of Chemical Engineering, University of Tehran, P.O. Box 11155/4563, Tehran (Iran, Islamic Republic of); Khodadadi, Abbas Ali, E-mail: Khodadad@ut.ac.ir [Catalysis and Nanostructured Materials Research Laboratory, School of Chemical Engineering, University of Tehran, P.O. Box 11155/4563, Tehran (Iran, Islamic Republic of); Choolaei, Mohammadmehdi, E-mail: Choolaeimm@ripi.ir [Catalysis and Nanotechnology Research Division, Research Institute of Petroleum Industry (RIPI), P.O. Box 14665-1998, Tehran (Iran, Islamic Republic of)

    2015-04-30

    Highlights: • Promoting effects of Cobalt oxide on methanol electro-oxidation over Pt/MWCNTs are investigated. • Higher activity, about 2.9 times, and enhanced stability are observed on Pt-CoO{sub x}/MWCNTs. • Electrochemical active surface area of Pt nanoparticles is significantly improved upon CoO{sub x} addition. • Bi-functional mechanism is facilitated in presence of CoO{sub x}. - Abstract: The electro-catalytic behavior of Pt-CoO{sub x}/MWCNTs in methanol electro-oxidation reaction (MOR) is investigated and compared to that of Pt/MWCNTs. The electro-catalysts were synthesized by an impregnation method using NaBH{sub 4} as the reducing agent. The morphological and physical characteristics of samples are examined by XRD, TEM, ICP and EDS techniques. In the presence of CoO{sub x}, Pt nanoparticles were highly distributed on the support with an average particle size of 2 nm, an obvious decrease from 5.1 nm for Pt/MWCNTs. Cyclic voltammetry, CO-stripping, Chronoamperometry, and electrochemical impedance spectroscopy (EIS) measurements are used to study the electrochemical behavior of the electro-catalysts. The results revealed a considerable enhancement in the oxidation kinetics of CO{sub ads} on Pt active sites by the participation of CoO{sub x}. Compared to Pt/MWCNTs, Pt-CoO{sub x}/MWCNTs sample has a larger electrochemical active surface area (ECSA) and higher electro-catalytic activity and stability toward methanol electro-oxidation. According to the results of cyclic voltammetry, the forward anodic peak current density enhances more than 89% at the optimum atomic ratio of Pt:Co = 2:1. Furthermore, inclusion of cobalt oxide species causes the onset potential of methanol electro-oxidation reaction to shift 84 mV to negative values compared to that on Pt/MWCNTs. Based on EIS data, dehydrogenation of methanol is the rate-determining step of MOR on both Pt/MWCNTs and Pt-CoO{sub x}/MWCNTs, at small overpotentials. However, at higher overpotentials, the

  3. Advantage of redundancy in the controllability of remote handling manipulator

    International Nuclear Information System (INIS)

    Muhammad, Ali; Mattila, Jouni; Vilenius, Matti; Siuko, Mikko; Semeraro, Luigi

    2011-01-01

    To carry out a variety of remote handling operations inside the ITER divertor a Water Hydraulic MANipulator (WHMAN) and its control system have been designed and developed at Tampere University of Technology. The manipulator is installed on top of Cassette Multifunctional Mover (CMM) to assist during the cassette removal and installation operations. While CMM is designed to carry heavy components such as cassettes through the service ducts relying on positioning accuracy and repeatability, WHMAN is designed to execute a mix of remote handling operations using position trajectories and master-slave telemanipulation. WHMAN is composed of eight joints: six rotational and two translational. Since a manipulator requires only six joints to acquire the desired position and orientation in operational-space, the two additional joints of WHMAN provide the redundant degrees of mobility. This paper presents how this redundancy of WHMAN can be an advantage to optimize the execution of remote handling tasks. The paper also discusses an effective way to practically exploit the redundancy. The results show that the additional degrees of freedom can be utilized to improve the dynamic behavior of the manipulator.

  4. Manipulating the loss in electromagnetic cloaks for perfect wave absorption.

    Science.gov (United States)

    Argyropoulos, Christos; Kallos, Efthymios; Zhao, Yan; Hao, Yang

    2009-05-11

    We examine several ways to manipulate the loss in electro-magnetic cloaks, based on transformation electromagnetics. It is found that, by utilizing inherent electric and magnetic losses of metamaterials, perfect wave absorption can be achieved based on several popular designs of electromagnetic cloaks. A practical implementation of the absorber, consisting of ten discrete layers of metamaterials, is proposed. The new devices demonstrate super-absorptivity over a moderate wideband range, suitable for both microwave and optical applications. It is corroborated that the device is functional with a subwavelength thickness and, hence, advantageous compared to the conventional absorbers.

  5. Spectral photoluminescence for the characterization of excitation states in semiconductors and fluorescence solar collectors with manipulation of the in and out coupling of radiation

    Energy Technology Data Exchange (ETDEWEB)

    Knabe, Sebastian

    2011-05-20

    In this thesis results of different experiments are presented (e.g. angular dependent photoluminescence) to characterize the propagation of electro-magnetic radiation inside and out of absorbers using the examples of crystalline silicon and fluorescence collectors with and without manipulation of the in- and out-coupling of the radiation by photonic structures (opal and edge filters). Experimental results were compared with results from simulations of the propagation of radiation, which are based on the fundamental equations for the properties of electro-magnetic radiation like reflection, transmission, absorption or phase accumulation.

  6. Decentralized adaptive control of manipulators - Theory, simulation, and experimentation

    Science.gov (United States)

    Seraji, Homayoun

    1989-01-01

    The author presents a simple decentralized adaptive-control scheme for multijoint robot manipulators based on the independent joint control concept. The control objective is to achieve accurate tracking of desired joint trajectories. The proposed control scheme does not use the complex manipulator dynamic model, and each joint is controlled simply by a PID (proportional-integral-derivative) feedback controller and a position-velocity-acceleration feedforward controller, both with adjustable gains. Simulation results are given for a two-link direct-drive manipulator under adaptive independent joint control. The results illustrate trajectory tracking under coupled dynamics and varying payload. The proposed scheme is implemented on a MicroVAX II computer for motion control of the three major joints of a PUMA 560 arm. Experimental results are presented to demonstrate that trajectory tracking is achieved despite coupled nonlinear joint dynamics.

  7. Computer control of ET-RR-1 hot cell manipulators

    International Nuclear Information System (INIS)

    Effat, A.M.; Rahman, F.A.

    1990-01-01

    The hot cell designed for remote handling of radioactive materials are, in effect, integral systems of safety devices for attaining adequate radiological protection for the operating personnel. Their operation involve potential hazards that are sometimes of great magnitude. The effect of an incident or accident could thus be fatal. some of these incident are due to the collision of the manipulator slave side with the radioactive objectives. Therefore in order to minimize the probability of such type of incidents, the movement of the manipulators is suggested (in the present investigation) to be kept under computer control. A model have been developed to control the movement of the hot cell manipulators in the slave side for Egypt first research reactor ET-RR-1, specially in the hidden sectors. The model is based on the use of a microprocessor and some accessories fixed to the manipulators slave side in a special manner such that it prevents the manipulator from colliding with radioactive objects. This is achieved by a signal transmitted to a specially designed brake which controls the movement of the upper arm of the manipulator master side. The hardware design of the model as well as the software are presented in details

  8. Design and control considerations for industrial and space manipulators

    Science.gov (United States)

    Whitney, D. E.; Book, W. J.; Lynch, P. M.

    1974-01-01

    This paper is a progress report summarizing theoretical and practical results concerning integration of design and control aspects of manipulator arms for industrial or space applications. The relationships between task specifications, gross motions, fine motions, actuator type and location, size and strength of structural members, control servos and strategies, and overall design evaluation are briefly discussed, with some technical examples.

  9. Polymer Coatings Reduce Electro-osmosis

    Science.gov (United States)

    Herren, Blair J.; Snyder, Robert; Shafer, Steven G.; Harris, J. Milton; Van Alstine, James M.

    1989-01-01

    Poly(ethylene glycol) film controls electrostatic potential. Electro-osmosis in quartz or glass chambers reduced or reversed by coating inside surface of chambers with monomacromolecular layers of poly(ethylene glycol). Stable over long times. Electrostatic potential across surface of untreated glass or plastic chamber used in electro-phoresis is negative and attracts cations in aqueous electrolyte. Cations solvated, entrains flow of electrolyte migrating toward cathode. Electro-osmotic flow interferes with desired electrophoresis of particles suspended in electrolyte. Polymer coats nontoxic, transparent, and neutral, advantageous for use in electrophoresis.

  10. Impact Vibration Attenuation for a Flexible Robotic Manipulator through Transfer and Dissipation of Energy

    Directory of Open Access Journals (Sweden)

    Yushu Bian

    2013-01-01

    Full Text Available Due to the presence of system flexibility, impact can excite severe large amplitude vibration responses of the flexible robotic manipulator. This impact vibration exhibits characteristics of remarkable nonlinearity and strong energy. The main goal of this study is to put forward an energy-based control method to absorb and attenuate large amplitude impact vibration of the flexible robotic manipulator. The method takes advantage of internal resonance and is implemented through a vibration absorber based on the transfer and dissipation of energy. The addition of the vibration absorber to the flexible arm generates a coupling effect between vibration modes of the system. By means of analysis on 2:1 internal resonance, the exchange of energy is proven to be existent. The impact vibrational energy can be transferred from the arm to the absorber and dissipated through the damping of the absorber. The results of numerical simulations are promising and preliminarily verify that the method is feasible and can be used to combat large amplitude impact vibration of the flexible manipulator undergoing rigid motion.

  11. Advance of the new MA 23 force reflecting manipulator system

    International Nuclear Information System (INIS)

    Vertut, Jean; Coiffet, Philippe; Petit, Michel

    1976-01-01

    This new bilateral servo manipulator system is under development since 1974, in close cooperation between different french organizations with the leadership of the Commissariat a l'Energie Atomique. This Group is facing in the same Technology different applications covering nuclear remote manipulation, undersea remote work, second generation industrial robots and manipulators for handicaped persons. Brief description of the different arms ranging from 5kg to 20kg mass capacity are given with corresponding tested performances. They all use original electric DC actuators with extremely low friction and zero backlash, with only cables and tapes. System works in different modes: the direct master slave force reflecting mode, an advanced tape recording programmer, minicomputer control, and the combined modes. Work is concentrated on full dynamic control and force control by minicomputer

  12. Software Development for the Kinematic Analysis of a Lynx 6 Robot Arm

    OpenAIRE

    Baki Koyuncu; Mehmet Güzel

    2007-01-01

    The kinematics of manipulators is a central problem in the automatic control of robot manipulators. Theoretical background for the analysis of the 5 Dof Lynx-6 educational Robot Arm kinematics is presented in this paper. The kinematics problem is defined as the transformation from the Cartesian space to the joint space and vice versa. The Denavit-Harbenterg (D-H) model of representation is used to model robot links and joints in this study. Both forward and inverse kinematics solutions for th...

  13. Development of manipulator system with good portability and usability

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    Recently, accompanying the development of such elementary technologies as control technology, communication technology and ultrasmall, high accuracy sensor technology, the demand for the development of small, light weight manipulator systems which have the ingenuity comparable with human arms and can be moved and installed in any place becomes high. This time, by combining these elementary technologies with robot technology, the electric multi-articulate manipulator which can be applied to the ultrasonic flaw inspection of the welded parts and others in the various machinery and equipment for nuclear power stations was developed, and in the function confirmation test, the good results were obtained. This manipulator was developed jointly with five electric power companies. It was necessary to solve the subjects for the development. The system is composed of the equipment to be carried to a site and the equipment always installed in a control room, that is, ten components in total. The feature of the system is shown. The design of equipment constitution and control of the manipulator proper, the control technique, the function confirmation test and the results are reported. (K.I.)

  14. Rod-based Fabrication of Customizable Soft Robotic Pneumatic Gripper Devices for Delicate Tissue Manipulation.

    Science.gov (United States)

    Low, Jin-Huat; Yeow, Chen-Hua

    2016-08-02

    Soft compliant gripping is essential in delicate surgical manipulation for minimizing the risk of tissue grip damage caused by high stress concentrations at the point of contact. It can be achieved by complementing traditional rigid grippers with soft robotic pneumatic gripper devices. This manuscript describes a rod-based approach that combined both 3D-printing and a modified soft lithography technique to fabricate the soft pneumatic gripper. In brief, the pneumatic featureless mold with chamber component is 3D-printed and the rods were used to create the pneumatic channels that connect to the chamber. This protocol eliminates the risk of channels occluding during the sealing process and the need for external air source or related control circuit. The soft gripper consists of a chamber filled with air, and one or more gripper arms with a pneumatic channel in each arm connected to the chamber. The pneumatic channel is positioned close to the outer wall to create different stiffness in the gripper arm. Upon compression of the chamber which generates pressure on the pneumatic channel, the gripper arm will bend inward to form a close grip posture because the outer wall area is more compliant. The soft gripper can be inserted into a 3D-printed handling tool with two different control modes for chamber compression: manual gripper mode with a movable piston, and robotic gripper mode with a linear actuator. The double-arm gripper with two actuatable arms was able to pick up objects of sizes up to 2 mm and yet generate lower compressive forces as compared to elastomer-coated and non-coated rigid grippers. The feasibility of having other designs, such as single-arm or hook gripper, was also demonstrated, which further highlighted the customizability of the soft gripper device, and it's potential to be used in delicate surgical manipulation to reduce the risk of tissue grip damage.

  15. A review of magnetic resonance imaging compatible manipulators in surgery.

    Science.gov (United States)

    Elhawary, H; Zivanovic, A; Davies, B; Lampérth, M

    2006-04-01

    Developments in magnetic resonance imaging (MRI), coupled with parallel progress in the field of computer-assisted surgery, mean that an ideal environment has been created for the development of MRI-compatible robotic systems and manipulators, capable of enhancing many types of surgical procedure. However, MRI does impose severe restrictions on mechatronic devices to be used in or around the scanners. In this article a review of the developments in the field of MRI-compatible surgical manipulators over the last decade is presented. The manipulators developed make use of different methods of actuation, but they can be reduced to four main groups: actuation transmitted through hydraulics, pneumatic actuators, ultrasonic motors based on the piezoceramic principle and remote manual actuation. Progress has been made concerning material selection, position sensing, and different actuation techniques, and design strategies have been implemented to overcome the multiple restrictions imposed by the MRI environment. Most systems lack the clinical validation needed to continue on to commercial products.

  16. Parallel control method for a bilateral master-slave manipulator

    International Nuclear Information System (INIS)

    Miyazaki, Tomohiro; Hagihara, Shiro

    1989-01-01

    In this paper, a new control method for a bilateral master-slave manipulator is proposed. The proposed method yields stable and fast response of the control system. These are essential to obtain a precise position control and a sensitive force reflection control. In the conventional position-force control method, each control loop of the master and the slave arms are connected in series to construct a bilateral control loop. Therefore the total phase lag through the bilateral control loop becomes twice as much as that of one arm control. Such phase lag makes the control system unstable and control performance worse. To improve the stability and the control performance, we propose 'parallel control method.' In the proposed method, the control loops of the master and the slave arms are connected in parallel so that the total phase lag is reduced to as much as that of one arm. The stability condition of the proposed method is studied and it is proved that the stability of this method can be guaranteed independent of the rigidness of a reaction surface and the position/force ratio between the master and the slave arms while the stability of the conventional method depends on them. (author)

  17. Stud manipulating device

    International Nuclear Information System (INIS)

    Bunyan, T.W.

    1980-01-01

    A device for inserting and removing studs from bores in a workpiece, for example a nuclear reactor vessel, comprises manipulating devices for operating on individual studs, each capable of tensioning a stud slackening a working nut on the stud, and subsequently removing the stud from the bore. A ring has dogs which can engage working nut recesses to interlock with the nut against relative rotation. Motors coupled to the ring rotate the working nut. A top nut is coupled to the motors to rotate the nut and screw it onto the stud. The top nut with other device parts can be raised and lowered on a tube by a hydraulic actuator. A hydraulic load cell between the top nut and a stool on the workpiece is pressurised to tension the stud by means of the top nut and thus facilitate rotation of the working nut when tightening or slackening. A dog clutch mechanism engages a stud end fitting against relative axial and rotational movement. The mechanism is raised and lowered on a guide member by an actuator. The mechanism has a tubular member and the drive coupling for the motors to the top nut includes a tubular member. Tubular members carry teeth which are engaged when the top nut is raised and the clutch mechanism is lowered, to provide a coupling between the motors and the mechanism for rotating the stud. (U.K.)

  18. Robotically facilitated virtual rehabilitation of arm transport integrated with finger movement in persons with hemiparesis

    OpenAIRE

    Davidow Amy; Lafond Ian; Saleh Soha; Qiu Qinyin; Fluet Gerard G; Merians Alma S; Adamovich Sergei V

    2011-01-01

    Abstract Background Recovery of upper extremity function is particularly recalcitrant to successful rehabilitation. Robotic-assisted arm training devices integrated with virtual targets or complex virtual reality gaming simulations are being developed to deal with this problem. Neural control mechanisms indicate that reaching and hand-object manipulation are interdependent, suggesting that training on tasks requiring coordinated effort of both the upper arm and hand may be a more effective me...

  19. Effect of arm swing strategy on local dynamic stability of human gait.

    Science.gov (United States)

    Punt, Michiel; Bruijn, Sjoerd M; Wittink, Harriet; van Dieën, Jaap H

    2015-02-01

    Falling causes long term disability and can even lead to death. Most falls occur during gait. Therefore improving gait stability might be beneficial for people at risk of falling. Recently arm swing has been shown to influence gait stability. However at present it remains unknown which mode of arm swing creates the most stable gait. To examine how different modes of arm swing affect gait stability. Ten healthy young male subjects volunteered for this study. All subjects walked with four different arm swing instructions at seven different gait speeds. The Xsens motion capture suit was used to capture gait kinematics. Basic gait parameters, variability and stability measures were calculated. We found an increased stability in the medio-lateral direction with excessive arm swing in comparison to normal arm swing at all gait speeds. Moreover, excessive arm swing increased stability in the anterior-posterior and vertical direction at low gait speeds. Ipsilateral and inphase arm swing did not differ compared to a normal arm swing. Excessive arm swing is a promising gait manipulation to improve local dynamic stability. For excessive arm swing in the ML direction there appears to be converging evidence. The effect of excessive arm swing on more clinically relevant groups like the more fall prone elderly or stroke survivors is worth further investigating. Excessive arm swing significantly increases local dynamic stability of human gait. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Isotropy of an Upper Limb Exoskeleton and the Kinematics and Dynamics of the Human Arm

    Directory of Open Access Journals (Sweden)

    Joel C. Perry

    2009-01-01

    Full Text Available The integration of human and robot into a single system offers remarkable opportunities for a new generation of assistive technology. Despite the recent prominence of upper limb exoskeletons in assistive applications, the human arm kinematics and dynamics are usually described in single or multiple arm movements that are not associated with any concrete activity of daily living (ADL. Moreover, the design of an exoskeleton, which is physically linked to the human body, must have a workspace that matches as close as possible with the workspace of the human body, while at the same time avoid singular configurations of the exoskeleton within the human workspace. The aims of the research reported in this manuscript are (1 to study the kinematics and the dynamics of the human arm during daily activities in a free and unconstrained environment, (2 to study the manipulability (isotropy of a 7-degree-of-freedom (DOF-powered exoskeleton arm given the kinematics and the dynamics of the human arm in ADLs. Kinematic data of the upper limb were acquired with a motion capture system while performing 24 daily activities from six subjects. Utilising a 7-DOF model of the human arm, the equations of motion were used to calculate joint torques from measured kinematics. In addition, the exoskeleton isotropy was calculated and mapped with respect to the spacial distribution of the human arm configurations during the 24 daily activities. The results indicate that the kinematic joint distributions representing all 24 actions appear normally distributed except for elbow flexion–extension with the emergence of three modal centres. Velocity and acceleration components of joint torque distributions were normally distributed about 0 Nm, whereas gravitational component distributions varied with joint. Additionally, velocity effects were found to contribute only 1/100th of the total joint torque, whereas acceleration components contribute 1/10th of the total torque at the

  1. Dual arm master controller development

    International Nuclear Information System (INIS)

    Kuban, D.P.; Perkins, G.S.

    1985-01-01

    The advanced servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented. This work was performed as part of the Consolidated Fuel Reprocessing Program at the Oak Ridge National Laboratory. 5 refs., 7 figs., 1 tab

  2. Switching sliding mode force tracking control of piezoelectric-hydraulic pump-based friction element actuation systems for automotive transmissions

    Science.gov (United States)

    Kim, Gi-Woo; Wang, K. W.

    2009-08-01

    In this study, a nonlinear sliding-mode controller is designed for force tracking of a piezoelectric-hydraulic pump (PHP)-based actuation system, which is developed to replace the current electro-hydraulic actuation systems for automatic transmission (AT) friction elements, such as band brakes or clutches. By utilizing the PHP, one can eliminate the various hydraulic components (oil pump, regulating valve and control valve) in current ATs and achieve a simpler configuration with more efficient operation. With the derived governing equation of motion of the PHP-based actuation system integrated with the friction element (band brake), a switching control law is synthesized based on the sliding-mode theory. To evaluate the effectiveness of the proposed control law, its force tracking performance for the engagement of a friction element during an AT 1\\to 2 up-shift is examined experimentally. It is shown that one can successfully track the desired force trajectory for AT shift control with small tracking error. This study demonstrates the potential of the PHP as a new controllable actuation system for AT friction elements.

  3. Switching sliding mode force tracking control of piezoelectric-hydraulic pump-based friction element actuation systems for automotive transmissions

    International Nuclear Information System (INIS)

    Kim, Gi-Woo; Wang, K W

    2009-01-01

    In this study, a nonlinear sliding-mode controller is designed for force tracking of a piezoelectric-hydraulic pump (PHP)-based actuation system, which is developed to replace the current electro-hydraulic actuation systems for automatic transmission (AT) friction elements, such as band brakes or clutches. By utilizing the PHP, one can eliminate the various hydraulic components (oil pump, regulating valve and control valve) in current ATs and achieve a simpler configuration with more efficient operation. With the derived governing equation of motion of the PHP-based actuation system integrated with the friction element (band brake), a switching control law is synthesized based on the sliding-mode theory. To evaluate the effectiveness of the proposed control law, its force tracking performance for the engagement of a friction element during an AT 1→2 up-shift is examined experimentally. It is shown that one can successfully track the desired force trajectory for AT shift control with small tracking error. This study demonstrates the potential of the PHP as a new controllable actuation system for AT friction elements

  4. Hydraulic limits preceding mortality in a piñon-juniper woodland under experimental drought.

    Science.gov (United States)

    Plaut, Jennifer A; Yepez, Enrico A; Hill, Judson; Pangle, Robert; Sperry, John S; Pockman, William T; McDowell, Nate G

    2012-09-01

    Drought-related tree mortality occurs globally and may increase in the future, but we lack sufficient mechanistic understanding to accurately predict it. Here we present the first field assessment of the physiological mechanisms leading to mortality in an ecosystem-scale rainfall manipulation of a piñon-juniper (Pinus edulis-Juniperus monosperma) woodland. We measured transpiration (E) and modelled the transpiration rate initiating hydraulic failure (E(crit) ). We predicted that isohydric piñon would experience mortality after prolonged periods of severely limited gas exchange as required to avoid hydraulic failure; anisohydric juniper would also avoid hydraulic failure, but sustain gas exchange due to its greater cavitation resistance. After 1 year of treatment, 67% of droughted mature piñon died with concomitant infestation by bark beetles (Ips confusus) and bluestain fungus (Ophiostoma spp.); no mortality occurred in juniper or in control piñon. As predicted, both species avoided hydraulic failure, but safety margins from E(crit) were much smaller in piñon, especially droughted piñon, which also experienced chronically low hydraulic conductance. The defining characteristic of trees that died was a 7 month period of near-zero gas exchange, versus 2 months for surviving piñon. Hydraulic limits to gas exchange, not hydraulic failure per se, promoted drought-related mortality in piñon pine. © 2012 Blackwell Publishing Ltd.

  5. High degree-of-freedom dynamic manipulation

    Science.gov (United States)

    Murphy, Michael P.; Stephens, Benjamin; Abe, Yeuhi; Rizzi, Alfred A.

    2012-06-01

    The creation of high degree of freedom dynamic mobile manipulation techniques and behaviors will allow robots to accomplish difficult tasks in the field. We are investigating the use of the body and legs of legged robots to improve the strength, velocity, and workspace of an integrated manipulator to accomplish dynamic manipulation. This is an especially challenging task, as all of the degrees of freedom are active at all times, the dynamic forces generated are high, and the legged system must maintain robust balance throughout the duration of the tasks. To accomplish this goal, we are utilizing trajectory optimization techniques to generate feasible open-loop behaviors for our 28 dof quadruped robot (BigDog) by planning the trajectories in a 13 dimensional space. Covariance Matrix Adaptation techniques are utilized to optimize for several criteria such as payload capability and task completion speed while also obeying constraints such as torque and velocity limits, kinematic limits, and center of pressure location. These open-loop behaviors are then used to generate feed-forward terms, which are subsequently used online to improve tracking and maintain low controller gains. Some initial results on one of our existing balancing quadruped robots with an additional human-arm-like manipulator are demonstrated on robot hardware, including dynamic lifting and throwing of heavy objects 16.5kg cinder blocks, using motions that resemble a human athlete more than typical robotic motions. Increased payload capacity is accomplished through coordinated body motion.

  6. Medically relevant ElectroNeedle technology development.

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Carrie Frances; Thomas, Michael Loren; McClain, Jaime L.; Harper, Jason C.; Achyuthan, Komandoor E.; Ten Eyck, Gregory A.

    2008-11-01

    ElectroNeedles technology was developed as part of an earlier Grand Challenge effort on Bio-Micro Fuel Cell project. During this earlier work, the fabrication of the ElectroNeedles was accomplished along with proof-of-concept work on several electrochemically active analytes such as glucose, quinone and ferricyanide. Additionally, earlier work demonstrated technology potential in the field of immunosensors by specifically detecting Troponin, a cardiac biomarker. The current work focused upon fabrication process reproducibility of the ElectroNeedles and then using the devices to sensitively detect p-cresol, a biomarker for kidney failure or nephrotoxicity. Valuable lessons were learned regarding fabrication assurance and quality. The detection of p-cresol was accomplished by electrochemistry as well as using fluorescence to benchmark ElectroNeedles performance. Results from these studies will serve as a guide for the future fabrication processes involving ElectroNeedles as well as provide the groundwork necessary to expand technology applications. One paper has been accepted for publication acknowledging LDRD funding (K. E. Achyuthan et al, Comb. Chem. & HTS, 2008). We are exploring the scope for a second paper describing the applications potential of this technology.

  7. Novel electro-hydraulic position control system for primary mirror supporting system

    Directory of Open Access Journals (Sweden)

    Xiongbin Peng

    2016-05-01

    Full Text Available In the field of modern large-scale telescope, primary mirror supporting system technology faces the difficulties of theoretically uniform output force request and bias compensation. Therefore, a novel position control system combining hydraulic system with servo motor system is introduced. The novel system ensures uniform output force on supporting points without complicating the mechanical structure. The structures of both primary mirror supporting system and novel position system are described. Then, the mathematical model of novel position control system is derived for controller selection. A proportional–derivative controller is adopted for simulations and experiments of step response and triangle path tracking. The results show that proportional–derivative controller guarantees the system with micrometer-level positioning ability. A modified proportional–derivative controller is utilized to promote system behavior with faster response overshoot. The novel position control system is then applied on primary mirror supporting system. Coupling effect is observed among actuator partitions, and relocation of virtual pivot supporting point is chosen as the decoupling measurement. The position keeping ability of the primary mirror supporting system is verified by rotating the mirror cell at a considerably high rate. The experiment results show that the decoupled system performs better with smaller bias and shorter recovery time.

  8. An Experimental Study on Operability of Master-Slave Manipulator System using Human–in–the-Loop Type Simulator

    Directory of Open Access Journals (Sweden)

    Tashiro Yosuke

    2017-01-01

    Full Text Available Double arm Master-Slave (M-S manipulator has been attracted the attention of the robotics researchers today. The micro surgery is one of the big targets which M-S manipulator is expected to effectively perform. This paper describes about the human in the loop (HIL simulator consisted of the prototype master manipulator and the virtual simulator of slave manipulator. Today, we have a challenge injecting drugs to a chick embryo’s blood vessels that are enough cultured in an artificial eggshell. The M-S manipulator is expected to apply for such a work like a micro surgery, ex. catching a blood vessel and sticking a cylinder. The embryo is extremely sensitive so that M-S manipulator should have both high operability and high accuracy movement. To evaluate the M-S manipulator quantitatively, we develop the human in the loop (HIL simulator. The simulator is consisted with the prototype master manipulator and the virtual slave manipulator.

  9. Rotational manipulation of single cells and organisms using acoustic waves.

    Science.gov (United States)

    Ahmed, Daniel; Ozcelik, Adem; Bojanala, Nagagireesh; Nama, Nitesh; Upadhyay, Awani; Chen, Yuchao; Hanna-Rose, Wendy; Huang, Tony Jun

    2016-03-23

    The precise rotational manipulation of single cells or organisms is invaluable to many applications in biology, chemistry, physics and medicine. In this article, we describe an acoustic-based, on-chip manipulation method that can rotate single microparticles, cells and organisms. To achieve this, we trapped microbubbles within predefined sidewall microcavities inside a microchannel. In an acoustic field, trapped microbubbles were driven into oscillatory motion generating steady microvortices which were utilized to precisely rotate colloids, cells and entire organisms (that is, C. elegans). We have tested the capabilities of our method by analysing reproductive system pathologies and nervous system morphology in C. elegans. Using our device, we revealed the underlying abnormal cell fusion causing defective vulval morphology in mutant worms. Our acoustofluidic rotational manipulation (ARM) technique is an easy-to-use, compact, and biocompatible method, permitting rotation regardless of optical, magnetic or electrical properties of the sample under investigation.

  10. Modeling and analysis of a meso-hydraulic climbing robot with artificial muscle actuation.

    Science.gov (United States)

    Chapman, Edward M; Jenkins, Tyler E; Bryant, Matthew

    2017-07-10

    This paper presents a fully coupled electro-hydraulic model of a bio-inspired climbing robot actuated by fluidic artificial muscles (FAMs). This analysis expands upon previous FAM literature by considering not only the force and contraction characteristics of the actuator, but the complete hydraulic and electromechanical circuits as well as the dynamics of the climbing robot. This analysis allows modeling of the time-varying applied pressure, electrical current, and actuator contraction for accurate prediction of the robot motion, energy consumption, and mechanical work output. The developed model is first validated against mechanical and electrical data collected from a proof-of-concept prototype robot. The model is then employed to study the system-level sensitivities of the robot locomotion efficiency and average climbing speed to several design and operating parameters. The results of this analysis demonstrate that considering only the transduction efficiency of the FAM actuators is insufficient to maximize the efficiency of the complete robot, and that a holistic approach can lead to significant improvements in performance. © 2017 IOP Publishing Ltd.

  11. Robotic dismantlement systems at the CP-5 reactor D and D project

    International Nuclear Information System (INIS)

    Seifert, L. S.

    1998-01-01

    The Chicago Pile 5 (CP-5) Research Reactor Facility is currently undergoing decontamination and decommissioning (D and D) at the Argonne National Laboratory (ANL) Illinois site. CP-5 was the principle nuclear reactor used to produce neutrons for scientific research at Argonne from 1954 to 1979. The CP-5 reactor was a heavy-water cooled and moderated, enriched uranium-fueled reactor with a graphite reflector. The CP-5 D and D project includes the disassembly, segmentation and removal of all the radioactive components, equipment and structures associated with the CP-5 facility. The Department of Energy's Robotics Technology Development Program and the Federal Energy Technology Center, Morgantown Office provided teleoperated, remote systems for use in the dismantlement of the CP-5 reactor assembly for tasks requiring remote dismantlement as part of the EM-50 Large-Scale Demonstration Program (LSDP). The teleoperated systems provided were the Dual Arm Work Platform (DAWP), the Rosie Mobile Teleoperated Robot Work System (ROSIE), and a remotely-operated crane control system with installed swing-reduction control system. Another remotely operated apparatus, a Brokk BM250, was loaned to ANL by the Princeton Plasma Physics Laboratory (PPPL). This machine is not teleoperated and was not part of the LSDP, but deserves some mention in this discussion. The DAWP is a robotic dismantlement system that includes a pair of Schilling Robotic Systems Titan III hydraulic manipulator arms mounted to a specially designed support platform: a hydraulic power unit (HPU) and a remote operator console. The DAWP is designed to be crane-suspended for remote positioning. ROSIE, developed by RedZone Robotics, Inc. is a mobile, electro-hydraulic, omnidirectional platform with a heavy-duty telescoping boom mounted to the platform's deck. The work system includes the mobile platform (locomotor), a power distribution unit (PDU) and a remote operator console. ROSIE moves about the reactor building

  12. Robust Position Control of Electro-mechanical Systems

    OpenAIRE

    Rong Mei; Mou Chen

    2013-01-01

    In this work, the robust position control scheme is proposed for the electro-mechanical system using the disturbance observer and backstepping control method. To the external unknown load of the electro-mechanical system, the nonlinear disturbance observer is given to estimate the external unknown load. Combining the output of the developed nonlinear disturbance observer with backstepping technology, the robust position control scheme is proposed for the electro-mechanical system. The stabili...

  13. Kinematic modeling of a 7-degree of freedom spatial hybrid manipulator for medical surgery.

    Science.gov (United States)

    Singh, Amanpreet; Singla, Ekta; Soni, Sanjeev; Singla, Ashish

    2018-01-01

    The prime objective of this work is to deal with the kinematics of spatial hybrid manipulators. In this direction, in 1955, Denavit and Hartenberg proposed a consistent and concise method, known as D-H parameters method, to deal with kinematics of open serial chains. From literature review, it is found that D-H parameter method is widely used to model manipulators consisting of lower pairs. However, the method leads to ambiguities when applied to closed-loop, tree-like and hybrid manipulators. Furthermore, in the dearth of any direct method to model closed-loop, tree-like and hybrid manipulators, revisions of this method have been proposed from time-to-time by different researchers. One such kind of revision using the concept of dummy frames has successfully been proposed and implemented by the authors on spatial hybrid manipulators. In that work, authors have addressed the orientational inconsistency of the D-H parameter method, restricted to body-attached frames only. In the current work, the condition of body-attached frames is relaxed and spatial frame attachment is considered to derive the kinematic model of a 7-degree of freedom spatial hybrid robotic arm, along with the development of closed-loop constraints. The validation of the new kinematic model has been performed with the help of a prototype of this 7-degree of freedom arm, which is being developed at Council of Scientific & Industrial Research-Central Scientific Instruments Organisation Chandigarh to aid the surgeon during a medical surgical task. Furthermore, the developed kinematic model is used to develop the first column of the Jacobian matrix, which helps in providing the estimate of the tip velocity of the 7-degree of freedom manipulator when the first joint velocity is known.

  14. Manipulator motion planning for high-speed robotic laser cutting

    OpenAIRE

    Dolgui , Alexandre; Pashkevich , Anatol

    2009-01-01

    Abstract Recent advances in laser technology, and especially the essential increase of the cutting speed, motivate amending the existing robot path methods, which do not allow the complete utilisation of the actuator capabilities as well as neglect some particularities in the mechanical design of the wrist of the manipulator arm. This research addresses the optimisation of the 6-axes robot motions for continuous contour tracking while considering the redundancy caused by the tool a...

  15. Development program of two-arm bilateral servomanipulator system for nuclear fuel cycle facilities in PNC

    International Nuclear Information System (INIS)

    Kashihara, H.; Igarashi, M.; Maeda, M.; Nomizu, T.; Uematsu, K.

    1984-01-01

    PNC started the development program of a two-arm bilateral servomanipulator to improve remote maintenance in the planning of pilot plants for HLLW vitrification and FBR fuel reprocessing. In this paper, the development program of two-arm bilateral servomanipulators, signal and power transmissions, high performance viewing system, man-machine interface, and transporter system for manipulators will be presented. Also radiation tests for all components used in a hot cell are being performed to aid remote system design

  16. Electro-active sensor, method for constructing the same; apparatus and circuitry for detection of electro-active species

    Science.gov (United States)

    Buehler, Martin (Inventor)

    2009-01-01

    An electro-active sensor includes a nonconductive platform with a first electrode set attached with a first side of a nonconductive platform. The first electrode set serves as an electrochemical cell that may be utilized to detect electro-active species in solution. A plurality of electrode sets and a variety of additional electrochemical cells and sensors may be attached with the nonconductive platform. The present invention also includes a method for constructing the aforementioned electro-active sensor. Additionally, an apparatus for detection and observation is disclosed, where the apparatus includes a sealable chamber for insertion of a portion of an electro-active sensor. The apparatus allows for monitoring and detection activities. Allowing for control of attached cells and sensors, a dual-mode circuitry is also disclosed. The dual-mode circuitry includes a switch, allowing the circuitry to be switched from a potentiostat to a galvanostat mode.

  17. In Situ Bioremediation of Chlorinated Ethenes in Hydraulically-Tight Sediments: Challenges and Limitations

    Science.gov (United States)

    Zhang, M.; Yoshikawa, M.; Takeuchi, M.; Komai, T.

    2011-12-01

    Chlorinated ethenes, like perchloroethene (PCE) and trichloroethene (TCE), have been widely used by many industries, especially in developed countries like Japan. Because of their wide applications, lack of proper regulation, poor handing, storage and disposal practices in the past, chlorinated ethenes have become a type of the most prevalent contaminants for soils and groundwater pollution. For the sake of their degradability, bioremediation has been considered as a potentially cost-effective and environmentally friendly approach for cleanup of chlorinated ethenes in situ. In this presentation, we briefly overview the status of soil and groundwater pollution, the recent amendment of the Soil Contamination Countermeasures Act in Japan, comparison between the bioremediation and other techniques like pump and treat, and the mechanisms of reductive dechlorination, direct oxidation and co-metabolism of chlorinated ethenes. We then introduce and discuss some recent challenges and advancements in in-situ bioremediation including technologies for accelerating bio-degradation of chlorinated ethenes, technologies for assessing diffusive properties of dissolved hydrogen in hydraulically-tight soil samples, and combination of bioremediation with other techniques like electro-kinetic approach. Limiting factors that may cause incomplete remediation and/or ineffectiveness of bioremediation are examined from biochemical, geochemical and hydro-geological aspects. This study reconfirmed and illustrated that: 1) The key factor for an effective bioremediation is how to disperse a proper accelerating agent throughout the polluted strata, 2) The effective diffusion coefficient of dissolved hydrogen in geologic media is relatively big and is almost independent on their permeability, and 3) To effectively design and perform an accelerated bioremediation, a combination of natural migration with pressurized injection and/or other approaches, like electro-migration, for stimulating mass

  18. A compact plasmonic MOS-based 2×2 electro-optic switch

    Directory of Open Access Journals (Sweden)

    Ye Chenran

    2015-01-01

    Full Text Available We report on a three-waveguide electro-optic switch for compact photonic integrated circuits and data routing applications. The device features a plasmonic metal-oxide-semiconductor (MOS mode for enhanced light-matter-interactions. The switching mechanism originates from a capacitor-like design where the refractive index of the active medium, indium-tin-oxide, is altered via shifting the plasma frequency due to carrier accumulation inside the waveguide-based MOS structure. This light manipulation mechanism controls the transmission direction of transverse magnetic polarized light into either a CROSS or BAR waveguide port. The extinction ratio of 18 (7 dB for the CROSS (BAR state, respectively, is achieved via a gating voltage bias. The ultrafast broadband fJ/bit device allows for seamless integration with silicon-on-insulator platforms for low-cost manufacturing.

  19. A Research on the Primary Mirror Manipulator of Large Segmented-mirror Telescope

    Science.gov (United States)

    Zuo, H.

    2012-09-01

    Lagrange formulation is introduced, and the dynamic equations of the manipulator have been obtained by using the Lagrange method. Since the manipulator is a serious coupling system, the dynamic curve of the key joints is plotted by using the ADAMS software. According to the theoretical analysis, the manipulator for the primary mirror of LAMOST is designed and fabricated. The whole manipulator consists of three parts. The first part is the mechanical arm which is used to realize the high speed and the long distance location, and it is rebuilt from a small truck crane; The second part is a serial mechanical hand which is used to realize the low speed and the short distance location. It has six DOFs including the pitch, the rotate about the vertical axis, the elevation along the vertical axis, and two horizontal translations. Subsequently the structure is analyzed in the ANSYS software to confirm that the strength is enough and the displacement is in the tolerance; The third part is a mechanical wrist, in which part a hydraulic rod is used to keep the bottom of the mechanical hand horizontal. In chapter 6, the control characteristics of the whole manipulator are analyzed. Furthermore, the control method and flowchart are proposed. Based on this method the control device was selected. In the end of this paper, the main work and the results of this project are summarized. Further research is prospected and it provides a reference for the future large telescope projects.

  20. Highly-Integrated Hydraulic Smart Actuators and Smart Manifolds for High-Bandwidth Force Control

    Directory of Open Access Journals (Sweden)

    Victor Barasuol

    2018-06-01

    Full Text Available Hydraulic actuation is the most widely used alternative to electric motors for legged robots and manipulators. It is often selected for its high power density, robustness and high-bandwidth control performance that allows the implementation of force/impedance control. Force control is crucial for robots that are in contact with the environment, since it enables the implementation of active impedance and whole body control that can lead to a better performance in known and unknown environments. This paper presents the hydraulic Integrated Smart Actuator (ISA developed by Moog in collaboration with IIT, as well as smart manifolds for rotary hydraulic actuators. The ISA consists of an additive-manufactured body containing a hydraulic cylinder, servo valve, pressure/position/load/temperature sensing, overload protection and electronics for control and communication. The ISA v2 and ISA v5 have been specifically designed to fit into the legs of IIT’s hydraulic quadruped robots HyQ and HyQ-REAL, respectively. The key features of these components tackle 3 of today’s main challenges of hydraulic actuation for legged robots through: (1 built-in controllers running inside integrated electronics for high-performance control, (2 low-leakage servo valves for reduced energy losses, and (3 compactness thanks to metal additive manufacturing. The main contributions of this paper are the derivation of the representative dynamic models of these highly integrated hydraulic servo actuators, a control architecture that allows for high-bandwidth force control and their experimental validation with application-specific trajectories and tests. We believe that this is the first work that presents additive-manufactured, highly integrated hydraulic smart actuators for robotics.

  1. Use of the mini C-arm for wrist fractures - Establishing a diagnostic reference level

    International Nuclear Information System (INIS)

    Love, G. J.; Pillai, A.; Gibson, S.

    2008-01-01

    The establishment of diagnostic reference levels (DRLs) for all typical radiological examinations became mandatory following the implementation of the Ionising Radiations (Medical Exposure) Regulations Act 2000. At present, there are no national dosage guidelines in the UK regarding use of fluoroscopy in orthopaedic trauma. The increasing popularity of the mini C-arm image intensifier amongst surgeons has led to concerns regarding use of ionizing radiation by personnel who have not been trained in radiation protection. It is therefore essential to have formal protocols for use of the mini C-arm to comply with the law and to maintain safe clinical practice. It is attempted to provide dose data for wrist fracture manipulations that may be used as a basis for setting a DRL for this procedure. Screening times were recorded for 80 wrist manipulations in a fracture clinic setting using a mini C-arm image intensifier. A DRL was set using the third quartile value for screening time. The median screening time for wrist fractures was 20 s with a range from 1 to 177 s. The third quartile value for screening time was 34 s. This value can be used as a provisional DRL for wrist fracture manipulations. The DRL is a quantitative guide for the optimisation of radiological protection. IR(ME)R 2000 states that if it is consistently exceeded by an individual operator or a piece of equipment, investigation and remedial action must be taken. We recommend that trauma units establish their own local DRLs for common procedures as made mandatory by legislation. (authors)

  2. Manipulator Comparative Testing Program: Final report

    International Nuclear Information System (INIS)

    Draper, J.V.; Handel, S.J.; Sundstrom, E.; Herndon, J.N; Fujita, Y.; Maeda, M.

    1987-02-01

    The manipulator systems tested included the Meidensha BILARM 83A, the Central Research Laboratories Model M-2, and the GCA PaR Systems Model 6000. Six manipulator and control mode combinations were evaluated: (1) the BILARM in master/slave mode without force reflection, (2) the BILARM in master/slave mode with force reflection, (3) the Model M-2 in master/slave mode without force reflection, (4) the Model M-2 in master/slave mode with force reflection, (5) the BILARM with switchbox controls, and (6) the PaR 6000 with switchbox controls. The experiments examined differences between master/slave systems with and without force reflection and differences between master/slave systems and switchbox-controlled systems. A fourth experiment examined the relative contributions of the remote viewing system and the manipulator system to the performance of remote handling tasks. Results of the experiments showed that operators using the Model M-2 in master/slave mode had significantly faster times to completion than operators using the BILARM in master/slave mode, with about the same error rate per trial. Operators were slower using the BILARM with force reflection than without it, and they committed more errors. There was no statistically significant difference between force-reflection and nonforce-reflection conditions for the M-2 manipulator for any of the performance criteria. Tasks and procedures used in this testing were not sensitive to differences within any single system. No inferences about the effect of force reflection on remote task performance should be made from these data. The two manipulator systems in switchbox mode had significantly slower times to completion than any system in master/slave mode, with approximately the same error rate per trial. There were no significant differences between the BILARM in switchbox mode and the PaR arm

  3. Enhanced methanol electro-oxidation activity of Pt/MWCNTs electro-catalyst using manganese oxide deposited on MWCNTs

    International Nuclear Information System (INIS)

    Nouralishahi, Amideddin; Khodadadi, Abbas Ali; Mortazavi, Yadollah; Rashidi, Alimorad; Choolaei, Mohammadmehdi

    2014-01-01

    Highlights: • Promoting effects of manganese oxide (MnO x ) on methanol electro-oxidation over Pt/MWCNTs are studied. • 3.3 times higher activity and improved stability are observed on Pt/MnO x -MWCNTs in MOR. • Both hydrogen spill over and bi-functional mechanism are facilitated in presence of MnO x . • MnO x significantly enhances electrochemical active surface area and dispersion of Pt nanoparticles. • Proton conductivity of electrocatalyst layer is improved upon MnO x incorporation. - Abstract: Electro-oxidation of methanol on platinum nanoparticles supported on a nanocomposite of manganese oxide (MnO x ) and multi-wall carbon nanotubes (MWCNTs) is investigated. The morphology, structure, and chemical composition of the electro-catalysts are characterized by TEM, XRD, EDS, TGA, and H 2 -TPR. The electro-catalytic properties of electrodes are examined by cyclic voltammetry, CO-stripping, electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV). Compared to Pt/MWCNTs, the Pt/MnO x -MWCNTs electro-catalyst exhibits about 3.3 times higher forward peak current density, during cyclic voltammetry, and 4.6 times higher exchange current density in methanol electro-oxidation reaction. In addition, deposition of manganese oxide onto MWCNTs dramatically increases the electrochemical active surface area from 29.7 for Pt/MWCNTs to 89.4 m 2 g −1 Pt for Pt/MnO x -MWCNTs. The results of long-term cyclic voltammetry show superior stability of Pt nanoparticles upon addition of manganese oxide to the support. Furthermore, the kinetics of formation of the chemisorbed OH groups improves upon manganese oxide incorporation. This leads to a lower onset potential of CO ads oxidation on Pt/MnO x -MWCNTs than on Pt/MWCNTs

  4. Project W-340 tank 241-C-106 manipulator system closeout summary

    International Nuclear Information System (INIS)

    McDaniel, L.B.

    1995-02-01

    This document summarizes the work that was ongoing when Project W-340 was put on hold. Project W-340: Tank 241-C-106 Manipulator Retrieval System, was a candidate FY98 Major System Acquisition. The project was to develop, procure and deploy a Long Reach Manipulator (LRM) waste retrieval system to provide an alternate method to completing the in-tank demonstration of Single Shell Tank waste retrieval technology. The need for enhanced capabilities derives from (1) the inability of the baseline technology to retrieve certain hard waste forms; (2) uncertainty in the quantity of leakage which will be allowed. Numerous studies over the years have identified an arm architecture as a promising retrieval technology to overcome these concerns. The W340 project was intended to further develop and demonstrate this alternative, as part of selecting the best approach for all tanks. Prior to completing the effort, it was determined that an LRM system was too architecture specific and was envisioned to be too expensive for a one time demonstration of retrieval technology. At the time the work was stopped, an effort was underway to broaden the project scope to allow alternatives to an arm-based system

  5. Design, modeling and optimization of an underwater manipulator with four-bar mechanism and compliant linkage

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Sang Ok; Kim, Ji Hoon; Bae, Jang Ho; Kim, Jong Won [School of Mechanical and Aerospace Engineering, Seoul National University, Seoul (Korea, Republic of); Seo, Tae Won [School of Mechanical Engineering, Yeungnam University, Gyeongsan (Korea, Republic of)

    2016-09-15

    Underwater manipulators are very important for a robot to perform a specific operation in water. Conventional robot arm manipulators have been suggested for various operations but have not been suitable for repeated motion in gathering something. This paper presents a new underwater manipulator design for gathering things such as starfish on the sea floor. The manipulator is composed of a four-bar linkage to achieve repeated motion along a loop and compliant linkages to enhance the efficiency of the gathering work. Kinematic and quasi-static analyses were performed to calculate the loop path and the reaction force at the actuation point. Based on the analysis, optimal design was performed to maximize the working distance with the height difference and the reaction moments considered as constraints. A prototype was assembled to test the performance of the manipulator, and the empirical loop path was compared to simulation results.

  6. Design, modeling and optimization of an underwater manipulator with four-bar mechanism and compliant linkage

    International Nuclear Information System (INIS)

    Jin, Sang Ok; Kim, Ji Hoon; Bae, Jang Ho; Kim, Jong Won; Seo, Tae Won

    2016-01-01

    Underwater manipulators are very important for a robot to perform a specific operation in water. Conventional robot arm manipulators have been suggested for various operations but have not been suitable for repeated motion in gathering something. This paper presents a new underwater manipulator design for gathering things such as starfish on the sea floor. The manipulator is composed of a four-bar linkage to achieve repeated motion along a loop and compliant linkages to enhance the efficiency of the gathering work. Kinematic and quasi-static analyses were performed to calculate the loop path and the reaction force at the actuation point. Based on the analysis, optimal design was performed to maximize the working distance with the height difference and the reaction moments considered as constraints. A prototype was assembled to test the performance of the manipulator, and the empirical loop path was compared to simulation results

  7. The control of a manipulator by a computer model of the cerebellum.

    Science.gov (United States)

    Albus, J. S.

    1973-01-01

    Extension of previous work by Albus (1971, 1972) on the theory of cerebellar function to an application of a computer model of the cerebellum to manipulator control. Following a discussion of the cerebellar function and of a perceptron analogy of the cerebellum, particularly in regard to learning, an electromechanical model of the cerebellum is considered in the form of an IBM 1800 computer connected to a Rancho Los Amigos arm with seven degrees of freedom. It is shown that the computer memory makes it possible to train the arm on some representative sample of the universe of possible states and to achieve satisfactory performance.

  8. A novel adaptive force control method for IPMC manipulation

    International Nuclear Information System (INIS)

    Hao, Lina; Sun, Zhiyong; Su, Yunquan; Gao, Jianchao; Li, Zhi

    2012-01-01

    IPMC is a type of electro-active polymer material, also called artificial muscle, which can generate a relatively large deformation under a relatively low input voltage (generally speaking, less than 5 V), and can be implemented in a water environment. Due to these advantages, IPMC can be used in many fields such as biomimetics, service robots, bio-manipulation, etc. Until now, most existing methods for IPMC manipulation are displacement control not directly force control, however, under most conditions, the success rate of manipulations for tiny fragile objects is limited by the contact force, such as using an IPMC gripper to fix cells. Like most EAPs, a creep phenomenon exists in IPMC, of which the generated force will change with time and the creep model will be influenced by the change of the water content or other environmental factors, so a proper force control method is urgently needed. This paper presents a novel adaptive force control method (AIPOF control—adaptive integral periodic output feedback control), based on employing a creep model of which parameters are obtained by using the FRLS on-line identification method. The AIPOF control method can achieve an arbitrary pole configuration as long as the plant is controllable and observable. This paper also designs the POF and IPOF controller to compare their test results. Simulation and experiments of micro-force-tracking tests are carried out, with results confirming that the proposed control method is viable. (paper)

  9. Investigating Astromaterials Curation Applications for Dexterous Robotic Arms

    Science.gov (United States)

    Snead, C. J.; Jang, J. H.; Cowden, T. R.; McCubbin, F. M.

    2018-01-01

    The Astromaterials Acquisition and Curation office at NASA Johnson Space Center is currently investigating tools and methods that will enable the curation of future astromaterials collections. Size and temperature constraints for astromaterials to be collected by current and future proposed missions will require the development of new robotic sample and tool handling capabilities. NASA Curation has investigated the application of robot arms in the past, and robotic 3-axis micromanipulators are currently in use for small particle curation in the Stardust and Cosmic Dust laboratories. While 3-axis micromanipulators have been extremely successful for activities involving the transfer of isolated particles in the 5-20 micron range (e.g. from microscope slide to epoxy bullet tip, beryllium SEM disk), their limited ranges of motion and lack of yaw, pitch, and roll degrees of freedom restrict their utility in other applications. For instance, curators removing particles from cosmic dust collectors by hand often employ scooping and rotating motions to successfully free trapped particles from the silicone oil coatings. Similar scooping and rotating motions are also employed when isolating a specific particle of interest from an aliquot of crushed meteorite. While cosmic dust curators have been remarkably successful with these kinds of particle manipulations using handheld tools, operator fatigue limits the number of particles that can be removed during a given extraction session. The challenges for curation of small particles will be exacerbated by mission requirements that samples be processed in N2 sample cabinets (i.e. gloveboxes). We have been investigating the use of compact robot arms to facilitate sample handling within gloveboxes. Six-axis robot arms potentially have applications beyond small particle manipulation. For instance, future sample return missions may involve biologically sensitive astromaterials that can be easily compromised by physical interaction with

  10. Optimal Design of a 3-DOF Cable-Driven Upper Arm Exoskeleton

    Directory of Open Access Journals (Sweden)

    Zhu-Feng Shao

    2014-04-01

    Full Text Available With outstanding advantages, such as large workspace, flexibility, and lightweight and low inertia, cable-driven parallel manipulator shows great potential for application as the exoskeleton rehabilitation robot. However, the optimal design is still a challenging problem to be solved. In this paper, the optimal design of a 3-DOF (3-degree-of-freedom cable-driven upper arm exoskeleton is accomplished considering the force exerted on the arm. After analysis of the working conditions, two promising configurations of the cable-driven upper arm exoskeleton are put forward and design parameters are simplified. Then, candidate ranges of two angle parameters are determined with the proposed main workspace requirement. Further, global force indices are defined to evaluate the force applied to the arm by the exoskeleton, in order to enhance the system safety and comfort. Finally, the optimal design of each configuration is obtained with proposed force indices. In addition, atlases and charts given in this paper well illustrate trends of workspace and force with different values of design parameters.

  11. Tertiary treatment of landfill leachate by an integrated Electro-Oxidation/Electro-Coagulation/Electro-Reduction process: Performance and mechanism.

    Science.gov (United States)

    Ding, Jing; Wei, Liangliang; Huang, Huibin; Zhao, Qingliang; Hou, Weizhu; Kabutey, Felix Tetteh; Yuan, Yixing; Dionysiou, Dionysios D

    2018-06-05

    This study presents an integrated Electro-Oxidation/Electro-Coagulation/Electro-Reduction (EO/EC/ER) process for tertiary landfill leachate treatment. The influence of variables including leachate characteristics and operation conditions on the performance of EO/EC/ER process was evaluated. The removal mechanisms were explored by comparing results of anode, cathode, and bipolar electrode substitution experiments. The performance of the process in a scaled-up reactor was investigated to assure the feasibility of the process. Results showed that simultaneous removal of carbonaceous and nitrogenous pollutants was achieved under optimal conditions. Ammonia removal was due to the free chlorine generation of EO while organic matter degradation was achieved by both EO and EC processes. Nitrate removal was attributed to both ER and EC processes, with the higher removal achieved by ER process. In a scaled-up reactor, the EO/EC/ER process was able to remove 50-60% organic matter and 100% ammonia at charge of 1.5 Ah/L with energy consumption of 15 kW h/m 3 . Considering energy cost, the process is more efficient to meet the requirement of organic removal efficiency less than 70%. These results show the feasibility and potential of the EO/EC/ER process as an alternative tertiary treatment to achieve the simultaneous removal of organic matter, ammonia, nitrate, and color of leachate. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Improvement of the low-speed friction characteristics of a hydraulic piston pump by PVD-coating of TiN

    International Nuclear Information System (INIS)

    Hong, Yeh Sun; Lee, Sang Yul; Kim, Sung Hun; Lim, Hyun Sik

    2006-01-01

    The hydraulic pump of an Electro-hydrostatic Actuator should be able to quickly feed large volume of oil into hydraulic cylinder in order to reduce the response time. On the other hand, it should be also able to precisely dispense small amount of oil through low-speed operation so that the steady state position control error of the actuator can be accurately compensated. Within the scope of axial piston type hydraulic pumps, this paper is focused on the investigation how the surface treatment of their cylinder barrel with TiN plasma coating can contribute to the reduction of the friction and wear rate of valve plate in the low-speed range with mixed lubrication. The results showed that the friction torque of the valve plate mated with a TiN-coated cylinder barrel could be reduced to 22% of that with an uncoated original one when load pressure was 300 bar and rotational speed 100 rpm. It means that the torque efficiency of the test pump was expected to increase more than 1.3% under the same working condition. At the same time, the wear rate of the valve plate could be reduced to 40∼50%

  13. Modeling of Flexible Beams for Robotic Manipulators

    International Nuclear Information System (INIS)

    Martins, Jorge; Ayala Botto, Miguel; Costa, Jose sa da

    2002-01-01

    This work treats the problem of modeling robotic manipulators with structural flexibility. A mathematical model of a planar manipulator with a single flexible link is developed. This model is capable of reproducing nonlinear dynamic effects, such as the beam stiffening due to the centrifugal forces induced by the rotation of the joints, giving it the capability to predict reliable dynamic behaviors for a wide range of applications. On the other hand, the model complexity is reduced, in order to keep it amenable for analysis and controller design. The models found in current literature for control design of flexible manipulator arms present dynamic limitations for the sake of real time implementation in a control scheme. These limitations are the result of premature linearization in the formulation of the dynamics equations. In this paper, this common linearization is presented and their dynamic limitations uncovered. An alternative reliable model is then presented. The model is founded on two basic assumptions: inextensibility of the neutral fiber and moderate rotations of the cross sections in order to account for the foreshortening of the beam due to bending. Simulation and experimental results show that the proposed model has the closest dynamic behavior to the real beam

  14. Photoinduced electro-optics measurements of biosilica transformation to cristobalite

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, Ido [Department of Chemistry and the Institute of Nanotechnology, Bar-Ilan University, Ramat-Gan 52900 (Israel); Aluma, Yaniv; Ilan, Micha [Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801 (Israel); Kityk, Iwan [Institute of Electronic Systems, Faculty of Electrical Engineering, Czestochowa University, Czestochowa 42-201 (Poland); Mastai, Yitzhak, E-mail: Yitzhak.Mastai@biu.ac.il [Department of Chemistry and the Institute of Nanotechnology, Bar-Ilan University, Ramat-Gan 52900 (Israel)

    2015-03-15

    In this paper we studied the photoinduced electro optics effects in the thermal transformation process of biosilica to cristobalite, at a relatively low temperature and ambient pressure. This process was characterized by a variety of standards techniques with emphasis on linear electro optic effect measurements. Overall we demonstrated that photoinduced electro optics measurements are very sensitive to the transformation from amorphous structure of silica in the natural sponge samples to laminar string morphology of cristobalite. With this technique we could probe the change in the samples chirality from achiral bio silica to chiral cristobalite structure. Furthermore it is shown that natural biosilica have photoinduced linear electro optics respond indicating the chiral natural of biosilica. - Graphical abstract: The phase transformation of biosilica from marine sponges to Cristobalite under thermal treatment was investigated using photoinduced electro optics measurements. The figure shows the changes of the electro-optic coefficient of cristobalite and biosilica. - Highlights: • We examine phase transformation of biosilica. • We report transition from amorphous biosilica to crystalline Cristobalite. • Biosilica transformation to Cristobalite at temperature of 850 °C. • Biosilica transformation is studied with photoinduced measurements. • We examine changes in the photoinduced linear electro optics properties.

  15. Photoinduced electro-optics measurements of biosilica transformation to cristobalite

    International Nuclear Information System (INIS)

    Fuchs, Ido; Aluma, Yaniv; Ilan, Micha; Kityk, Iwan; Mastai, Yitzhak

    2015-01-01

    In this paper we studied the photoinduced electro optics effects in the thermal transformation process of biosilica to cristobalite, at a relatively low temperature and ambient pressure. This process was characterized by a variety of standards techniques with emphasis on linear electro optic effect measurements. Overall we demonstrated that photoinduced electro optics measurements are very sensitive to the transformation from amorphous structure of silica in the natural sponge samples to laminar string morphology of cristobalite. With this technique we could probe the change in the samples chirality from achiral bio silica to chiral cristobalite structure. Furthermore it is shown that natural biosilica have photoinduced linear electro optics respond indicating the chiral natural of biosilica. - Graphical abstract: The phase transformation of biosilica from marine sponges to Cristobalite under thermal treatment was investigated using photoinduced electro optics measurements. The figure shows the changes of the electro-optic coefficient of cristobalite and biosilica. - Highlights: • We examine phase transformation of biosilica. • We report transition from amorphous biosilica to crystalline Cristobalite. • Biosilica transformation to Cristobalite at temperature of 850 °C. • Biosilica transformation is studied with photoinduced measurements. • We examine changes in the photoinduced linear electro optics properties

  16. Variable geometry truss manipulators: A new type of robot for site inspection and remediation

    International Nuclear Information System (INIS)

    Naccarato, F.

    1996-01-01

    A new type of robotic manipulator has been developed that offers many potential advantages over conventional robot arms for site inspection and remediation. This new robot is based on the variable geometry truss manipulator (VGTM) concept which combines the structural properties of a truss with the dexterous capabilities of a manipulator. By substituting linear actuators for some of the fixed-length members within a truss, the structure can be made to change its overall shape. By coordinating the motion of these actuators appropriately, a VGTM can perform tasks that are relevant to hazardous waste clean-up, including deployment through curved ducts, probing into crevices and obstacle avoidance. Trussarm trademark, a prototype VGTM with twelve degrees-of-freedom, has been constructed by Dynacon Enterprises Limited

  17. Hydraulic structures

    CERN Document Server

    Chen, Sheng-Hong

    2015-01-01

    This book discusses in detail the planning, design, construction and management of hydraulic structures, covering dams, spillways, tunnels, cut slopes, sluices, water intake and measuring works, ship locks and lifts, as well as fish ways. Particular attention is paid to considerations concerning the environment, hydrology, geology and materials etc. in the planning and design of hydraulic projects. It also considers the type selection, profile configuration, stress/stability calibration and engineering countermeasures, flood releasing arrangements and scouring protection, operation and maintenance etc. for a variety of specific hydraulic structures. The book is primarily intended for engineers, undergraduate and graduate students in the field of civil and hydraulic engineering who are faced with the challenges of extending our understanding of hydraulic structures ranging from traditional to groundbreaking, as well as designing, constructing and managing safe, durable hydraulic structures that are economical ...

  18. Direct electro-optic effect in langasites and α-quartz

    Science.gov (United States)

    Ivanov, Vadim

    2018-05-01

    Strain-constant (clamped) electro-optic coefficients r11S of langasite La3Ga5SiO14 (LGS), langatate La3Ga5.5Ta0.5O14 (LGT), catangasite Ca3TaGa3Si2O14 (CTGS) and α-quartz are measured at 1540 nm in the frequency range of 3-25 MHz. Experimental ratio of clamped and unclamped electro-optic coefficients r11S/r11T is 0.97 for LGS, 0.91 for LGT, 0.31 for CTGS, and 0.49 for quartz. Most of direct electro-optic effect in LGS and LGT is associated with lanthanum ions: clamped electro-optic coefficient r11S in lanthanum-free CTGS is 14 times less than in LGS. Low piezoelectric contribution to unclamped electro-optic coefficient r11T makes LGS and LGT promising materials for electro-optic devices, whose performance can be deteriorated by piezoelectric effect, especially, for high-voltage optical voltage sensors.

  19. Allemagne et Pologne, ou la carte comme arme de propagande

    Directory of Open Access Journals (Sweden)

    Didier Le-Brun

    1990-03-01

    Full Text Available La cartographie n'est pas forcément neutre. Elle peut aussi devenir une arme de propagande. Ainsi, dans l'exemple du «Corridor polonais», pomme de discorde de l'Europe, durant tout l'entre-deux-guerres. et une des principales causes du second conflit mondial, des cartographes n'ont pas reculé devant les plus graves manipulations pour étayer leurs thèses.

  20. Hydraulic System Design of Hydraulic Actuators for Large Butterfly Valves

    Directory of Open Access Journals (Sweden)

    Ye HUANG

    2014-09-01

    Full Text Available Hydraulic control systems of butterfly valves are presently valve-controlled and pump-controlled. Valve-controlled hydraulic systems have serious power loss and generate much heat during throttling. Pump-controlled hydraulic systems have no overflow or throttling losses but are limited in the speed adjustment of the variable-displacement pump, generate much noise, pollute the environment, and have motor power that does not match load requirements, resulting in low efficiency under light loads and wearing of the variable-displacement pump. To overcome these shortcomings, this article designs a closed hydraulic control system in which an AC servo motor drives a quantitative pump that controls a spiral swinging hydraulic cylinder, and analyzes and calculates the structure and parameters of a spiral swinging hydraulic cylinder. The hydraulic system adjusts the servo motor’s speed according to the requirements of the control system, and the motor power matches the power provided to components, thus eliminating the throttling loss of hydraulic circuits. The system is compact, produces a large output force, provides stable transmission, has a quick response, and is suitable as a hydraulic control system of a large butterfly valve.

  1. Virtual prototype simulation of hydraulic shovel kinematics for spatial characterization in surface mining operations

    Energy Technology Data Exchange (ETDEWEB)

    S. Frimpong; Y. Li [University of Missouri-Rolla, Rolla, MO (United States). Department of Mining and Nuclear Engineering

    2005-12-15

    Hydraulic shovels are large-capacity equipment for excavating and loading dump trucks in constrained surface mining environments. Kinematics simulation of such equipment allows mine planning engineers to plan, design and control their spatial environments to achieve operating safety and efficiency. In this study, a hydraulic shovel was modelled as a mechanical manipulator with five degrees of freedom comprising the crawler, upper, boom, stick, bucket and bucket door components. The model was captured in a schematic diagram consisting of a six-bar linkage using the symbolic notation of Denavit and Hartenberg (Ho and Sriwattanathmma 1989). Homogeneous transformation matrices were used to capture the spatial configuration between adjacent links. The forward kinematics method was used to formulate the kinematics equations by attaching Cartesian coordinates to the schematic shovel diagram. Based on the kinematics model, a 3D virtual prototype of the hydraulic shovel was built in the Automatic Dynamic Analysis of Mechanical Systems (ADAMS) environment to simulate the motions of the hydraulic shovel with selected time steps. The simulator was validated using real-world data with animation and numerical analysis of the digging, swinging and dumping motions of the shovel machinery. The superimposed display of the deployment of the hydraulic shovel in three phases allows a detailed motion examination of the system. The numerical results of linear and angular displacements of the bucket tip and bucket door can be used to analyse the kinematics motion of the hydraulic shovel for its optimization. This simulator provides a solid foundation for further dynamics modelling and dynamic hydraulic shovel performance studies.

  2. Solar maximum mission panel jettison analysis remote manipulator system

    Science.gov (United States)

    Bauer, R. B.

    1980-01-01

    A study is presented of the development of the Remote Manipulator System (RMS) configurations for jettison of the solar panels on the Solar Maximum Mission/Multimission Satellite. A valid RMS maneuver between jettison configurations was developed. Arm and longeron loads and effector excursions due to the solar panel jettison were determined to see if they were within acceptable limits. These loads and end effector excursions were analyzed under two RMS modes, servos active in position hold submode, and in the brakes on mode.

  3. 2×2 polymeric electro-optic MZI switch using multimode interference couplers

    Science.gov (United States)

    Li, H. P.; Liao, J. K.; Tang, X. G.; Lu, R. G.; Liu, Y. Z.

    2009-11-01

    We present the design of a 2×2 photonic switch operating at 1.55-μm wavelength using electro-optic (EO) polymer waveguides. A Mach-Zehnder interferometer (MZI) is used to implement the proposed switch in which two identical 2×2 multimode interference (MMI) couplers are connected by two identical parallel single mode waveguides (two MZI arms). These two single-mode waveguides with electrodes allow modulating the phase difference between the two MZI arms based on the EO effect. In the proposed switch, the EO polymer, IPC-E/polysulfone, is used for the core layer of optical waveguides. UV15 and NOA61 are employed for the lower and upper cladding layers, respectively. The singlemode waveguide structure and 2×2 MMI coupler have been designed and analyzed for the EO switch. Device performance has been simulated using the beam propagation method. It is found that the switch performance is most sensitive to the MMI width and less sensitive to the MMI length. Optimized structure has been obtained for the 2×2 polymeric EO switch, which has a crosstalk level better than -25 dB and insertion loss lower than -1.8 dB. This performance makes the switch a potential candidate for practical use in photonic systems.

  4. The Department of Defense Critical Technologies Plan for the Committees on Armed Services United States Congress

    Science.gov (United States)

    1990-03-15

    mining operations, operation in hazardous indoor environments, and manipulator arms and appendages) are being pursued. Research in command and...through the memote identification of chemical effluents associated with drug factories and the remote location of marijuana fields by the multispectral

  5. Coordinated trajectory planning of dual-arm space robot using constrained particle swarm optimization

    Science.gov (United States)

    Wang, Mingming; Luo, Jianjun; Yuan, Jianping; Walter, Ulrich

    2018-05-01

    Application of the multi-arm space robot will be more effective than single arm especially when the target is tumbling. This paper investigates the application of particle swarm optimization (PSO) strategy to coordinated trajectory planning of the dual-arm space robot in free-floating mode. In order to overcome the dynamics singularities issue, the direct kinematics equations in conjunction with constrained PSO are employed for coordinated trajectory planning of dual-arm space robot. The joint trajectories are parametrized with Bézier curve to simplify the calculation. Constrained PSO scheme with adaptive inertia weight is implemented to find the optimal solution of joint trajectories while specific objectives and imposed constraints are satisfied. The proposed method is not sensitive to the singularity issue due to the application of forward kinematic equations. Simulation results are presented for coordinated trajectory planning of two kinematically redundant manipulators mounted on a free-floating spacecraft and demonstrate the effectiveness of the proposed method.

  6. Effect of robotic manipulation on unidirectional barbed suture integrity: evaluation of tensile strength and sliding force.

    Science.gov (United States)

    Kaushik, Dharam; Clay, Kevin; Hossain, S G M; Park, Eugene; Nelson, Carl A; LaGrange, Chad A

    2012-06-01

    One of the more challenging portions of robot-assisted radical prostatectomy (RARP) is the urethrovesical anastomosis. Because of this, a unidirectional absorbable barbed suture (V-Loc(™)) has been used to complete the anastomosis with better efficiency and less tension. The effect of robotic needle driver manipulation on barbed suture is unknown. Therefore, the aim of this study is to determine whether robotic manipulation decreases the tensile strength and peak sliding force of V-Loc barbed suture. Fifty-six V-Loc sutures were compared with 56 Maxon sutures. All sutures were 3-0 caliber. Half of the sutures in each group were manipulated with a da Vinci(®) robot large needle driver five times over a 5 cm length of suture. The other half was not manipulated. Breaking force was determined by placing sutures in a Bose ElectroForce load testing device. For sliding force testing, 28 V-Loc sutures were manipulated in the same fashion and compared with 28 nonmanipulated V-Loc sutures. Peak force needed to make the suture slip backward in porcine small intestine was determined to be the sliding force. Scanning electron microscopy of the barbs before and after robotic manipulation was also performed. The mean difference in breaking forces for manipulated vs nonmanipulated Maxon sutures was 4.52 N (P=0.004). The mean difference in breaking forces for manipulated vs nonmanipulated V-Loc sutures was 1.30 N (P=0.046). The manipulated V-Loc group demonstrated a lower peak sliding force compared with the nonmanipulated group (0.76 vs 0.88 N, P=0.199). Electron microscopy revealed minor structural damage to the barbs and suture. Tensile strength and peak sliding force of V-Loc suture is decreased by robotic manipulation. This is likely because of structural damage to the suture and barbs. This structural damage, however, is likely not clinically significant.

  7. Dual arm master controller concept: consolidated fuel reprocessing program

    International Nuclear Information System (INIS)

    Kuban, D.P.; Perkins, G.S.

    1984-04-01

    The Advanced Servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features result in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented. 6 references, 3 figures

  8. The JPL telerobotic Manipulator Control and Mechanization (MCM) subsystem

    Science.gov (United States)

    Hayati, Samad; Lee, Thomas S.; Tso, Kam; Backes, Paul; Kan, Edwin; Lloyd, J.

    1989-01-01

    The Manipulator Control and Mechanization (MCM) subsystem of the telerobot system provides the real-time control of the robot manipulators in autonomous and teleoperated modes and real time input/output for a variety of sensors and actuators. Substantial hardware and software are included in this subsystem which interfaces in the hierarchy of the telerobot system with the other subsystems. The other subsystems are: run time control, task planning and reasoning, sensing and perception, and operator control subsystem. The architecture of the MCM subsystem, its capabilities, and details of various hardware and software elements are described. Important improvements in the MCM subsystem over the first version are: dual arm coordinated trajectory generation and control, addition of integrated teleoperation, shared control capability, replacement of the ultimate controllers with motor controllers, and substantial increase in real time processing capability.

  9. Control of a Heavy-Lift Robotic Manipulator with Pneumatic Artificial Muscles

    Directory of Open Access Journals (Sweden)

    Ryan M. Robinson

    2014-04-01

    Full Text Available Lightweight, compliant actuators are particularly desirable in robotic systems intended for interaction with humans. Pneumatic artificial muscles (PAMs exhibit these characteristics and are capable of higher specific work than comparably-sized hydraulic actuators and electric motors. The objective of this work is to develop a control algorithm that can smoothly and accurately track the desired motions of a manipulator actuated by pneumatic artificial muscles. The manipulator is intended for lifting humans in nursing assistance or casualty extraction scenarios; hence, the control strategy must be capable of responding to large variations in payload over a large range of motion. The present work first investigates the feasibility of two output feedback controllers (proportional-integral-derivative and fuzzy logic, but due to the limitations of pure output feedback control, a model-based feedforward controller is developed and combined with output feedback to achieve improved closed-loop performance. The model upon which the controller is based incorporates the internal airflow dynamics, the physical parameters of the pneumatic muscles and the manipulator dynamics. Simulations were performed in order to validate the control algorithms, guide controller design and predict optimal gains. Using real-time interface software and hardware, the controllers were implemented and experimentally tested on the manipulator, demonstrating the improved capability.

  10. Feasibility study of an aerial manipulator interacting with a vertical wall

    Science.gov (United States)

    2017-06-01

    easier and cheaper to buy small multicopters and accessories, including sophisticated microcontrollers with large support through tutorials and...tasks was presented. The paper shows how to compute a matrix that projects the control law inputs for secondary tasks into the null space of the primary...arms, executes manipulation tasks. The paper improves a PID controller by means of a gain schedule technique, in which the gains are defined as a

  11. Analytical solution for the inverse kinematics of a redundant 7DoF manipulator with link offsets

    CSIR Research Space (South Africa)

    Singh, GK

    2010-10-01

    Full Text Available This work addresses the inverse kinematics problem for the 7 Degrees of Freedom Barrett Whole Arm Manipulator with link offsets. The presence of link offsets gives rise to the possibility of the in-elbow & out-elbow poses for a given end...

  12. Electro-optical Detection of Charged Particles

    International Nuclear Information System (INIS)

    Lazarus, D.M.

    2001-01-01

    The electric field of charged particles can induce transient changes in the polarization of light that produce sub-picosecond modulation of a laser beam. This is a consequence of the electro-optical effect in which the presence of the electric field in an electro-optical medium produces a change in the index of refraction of the medium resulting in a phase retardation between polarization components parallel and perpendicular to the electric field. We have observed the electro-optical effect due to 10 picosecond electron beam bunches with rise times that were limited by the bandwidth of our data acquisition system. This technology is being applied to particle beam diagnostics and has the potential to produce charged particle detectors combining excellent spatial resolution with unprecedented temporal precision.

  13. Keeping nuclear hazards at arm's length

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    As national and international regulations are tightened, the permitted radiation dose limits for nuclear workers are being lowered. But sharing the same dose among more people is raising nuclear industry costs. At the same time tasks such as refurbishment and decommissioning are multiplying as the nuclear industry matures. As a result of these trends, work in the nuclear power sector is increasingly having to be done under remote control. European and American progress in the technology was reported recently at a two-day international conference held in London and is reported here. In France 'Frastar' carries out tours of inspection inside reactor buildings under remote control and 'Suzy' is a finger walker robot carrying an arm which is a 3-actuator manipulator. Anglo-American advances are reported; robots with manipulator, cameras, audio signalling and the ability to climb stairs and ramps. A European Community research programme called Teleman was started in 1989 to develop advanced teleoperators for the nuclear industry. The projects underway in this programme are listed. (UK)

  14. Crosslinked polyimide electro-optic materials

    Energy Technology Data Exchange (ETDEWEB)

    Kowalczyk, T.C.; Kosc, T.Z.; Singer, K.D. [Case Western Reserve University, Department of Physics, Cleveland, Ohio 44106-7079 (United States); Beuhler, A.J.; Wargowski, D.A. [Amoco Research Center, Amoco Chemical Co., Naperville, Illinois 60566 (United States); Cahill, P.A.; Seager, C.H.; Meinhardt, M.B. [Sandia National Laboratories, Division 1811, Albuquerque, New Mexico 87185-1407 (United States); Ermer, S. [Lockheed Research and Development Division, Palo Alto, California 94304 (United States)

    1995-11-15

    We report studies of the optical and electro-optic properties of guest--host polymeric nonlinear optical materials based on aromatic, fluorinated, fully imidized, organic soluble, thermally, and photochemically crosslinkable, guest--host polyimides. We have introduced temperature stable nonlinear optical chromophores into these polyimides and studied optical losses, electric field poling, electro-optic properties, and orientational stability. We measured electro-optic coefficients of 5.5 and 12.0 pm/V for ((2,6-Bis(2-(3-(9-(ethyl)carbazolyl))ethenyl)4H-pyran-4-ylidene)propanedinitrile) (4-(Dicyanomethylene)-2-methyl-6-(p -dimethylaminostyryl)-4H-pyran) DCM-doped guest--host systems at 800 nm using a poling field of 1.3 MV/cm. Poling induced nonlinearities in single-layer films were in agreement with the oriented gas model, but were lower in three-layer films due to voltage division across the layers. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  15. Electro-optic methods for longitudinal bunch diagnostics at FLASH

    International Nuclear Information System (INIS)

    Steffen, B.R.

    2007-07-01

    Precise measurements of the temporal profile of sub-picosecond electron bunches are of high interest for the optimization and operation of VUV and X-ray free electron lasers. In this thesis, the shortest electro-optic signals measured so far for electron bunch diagnostics are presented, reaching a time resolution of better than 50 fs (rms). The e ects that introduce signal distortions and limit the time resolution are studied in numerical simulations for different electro-optic detection materials and techniques. The time resolution is mainly limited by lattice resonances of the electro-optic crystal. Electro-optic signals as short as 54 fs (rms) are obtained with gallium phosphide (GaP) crystals in a crossed polarizer detection scheme using temporally resolved electro-optic detection. Measuring near crossed polarization, where the electro-optic signal is proportional to the velocity field of the relativistic electron bunch, the shortest obtained signal width is 70 fs (rms). The electro-optic signals are compared to electron bunch shapes that are measured simultaneously with a transverse deflecting structure with 20 fs resolution. Numerical simulations using the bunch shapes as determined with the transverse deflecting cavity as input data are in excellent agreement with electro-optical signals obtained with GaP, both for temporally and spectrally resolved measurements. In the case of zinc telluride (ZnTe) the observed signals are slightly broader and significantly smaller than expected from simulations. These discrepancies are probably due to the poor optical quality of the available ZnTe crystals. (orig.)

  16. Electro-optic methods for longitudinal bunch diagnostics at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Steffen, B.R.

    2007-07-15

    Precise measurements of the temporal profile of sub-picosecond electron bunches are of high interest for the optimization and operation of VUV and X-ray free electron lasers. In this thesis, the shortest electro-optic signals measured so far for electron bunch diagnostics are presented, reaching a time resolution of better than 50 fs (rms). The e ects that introduce signal distortions and limit the time resolution are studied in numerical simulations for different electro-optic detection materials and techniques. The time resolution is mainly limited by lattice resonances of the electro-optic crystal. Electro-optic signals as short as 54 fs (rms) are obtained with gallium phosphide (GaP) crystals in a crossed polarizer detection scheme using temporally resolved electro-optic detection. Measuring near crossed polarization, where the electro-optic signal is proportional to the velocity field of the relativistic electron bunch, the shortest obtained signal width is 70 fs (rms). The electro-optic signals are compared to electron bunch shapes that are measured simultaneously with a transverse deflecting structure with 20 fs resolution. Numerical simulations using the bunch shapes as determined with the transverse deflecting cavity as input data are in excellent agreement with electro-optical signals obtained with GaP, both for temporally and spectrally resolved measurements. In the case of zinc telluride (ZnTe) the observed signals are slightly broader and significantly smaller than expected from simulations. These discrepancies are probably due to the poor optical quality of the available ZnTe crystals. (orig.)

  17. Electro Hydraulic Hitch Control

    DEFF Research Database (Denmark)

    Hansen, M. R.; Andersen, T. O.; Nielsen, B.

    2003-01-01

    for most of the systems are that they operate on the hydrailc actuators generally providing the motive forces for moving the implement and/or attachment, typically a plough. The basic idea and physical working principle are to use the implement, moveable relative to the vehicle, as a damper mass. The paper...

  18. Dismantling of JPDR reactor internals by underwater plasma arc cutting technique using robotic manipulator

    International Nuclear Information System (INIS)

    Yokota, M.

    1988-01-01

    The actual dismantling of JPDR started on December 4, 1986. As of now, equipment that surrounds the reactor has mostly been removed to provide working space in reactor containment prior to the dismantling of reactor internals. Some reactor internals have been successfully dismantled using the underwater arc cutting system with a robotic manipulator during the period of January to March 1988. The cutting system is composed of an underwater plasma arc cutting device and a robotic manipulator. The cut off reactor internals were core spray block, feedwater sparger and stabilizers for fuel upper grid tube. The plasma arc cutting device was developed to dismantle the reactor internals underwater. It mainly consists of a plasma torch, power and gas supply systems for the torch, and by-product treatment systems. It has the cutting ability of 130 mm thickness stainless steel underwater. The robotic manipulator has seven degrees of freedom of movement, enabling it to move in almost the same way as the arm of a human being. The arm of the robot is mounted on a supporting device which is suspended by three chains from the support structure set on a service floor. A plasma torch is griped by the robotic hand; its position to the structure to be cut is controlled from a remote control room, about 100 meters outside the reactor containment

  19. Development of a coupled tendon-driven 3D multi-joint manipulator. Investigation of tension transfer efficiency, optimal reel arrangement and tip positioning accuracy

    International Nuclear Information System (INIS)

    Horigome, Atsushi; Yamada, Hiroya; Hirose, Shigeo; Sen, Shin; Endo, Gen

    2017-01-01

    Long-reach robotic manipulators are expected to be used in the space where humans cannot work such as nuclear power plant disaster areas. We suggested a coupled tendon-driven articulated manipulator '3D CT-Arm' and developed a preliminary prototype 'Mini 3D CT-Arm' whose arm had 2.4 m length and 0.3 m width. In order to consider developing '3D CT-Arm' deeply, we discussed tension transfer efficiency of a tendon through pulleys, the arrangement of the maximum number of reels in a limited space and the tip positioning accuracy. Through many transfer efficiency experiments, we conclude that tension transfer efficiency of '3D CT-Arm' can reach over 88% in the worst case. We investigated non-interfering reels' arrangement in the base by full search in cases of up to 10 reels. In all simulations, V-shaped or W-shaped arrangement can support the most reels in a limited space. Therefore, we conclude this is the most optimal reels' arrangement. Finally, we carried out the positioning accuracy experiment with 'Mini 3D CT-Arm' via motion capture system. Although the tip position had a 2 to 41 mm error between the desired value and the measured value by potentiometer, a 29 to 95 mm error between the desired value and the measured value was measured by motion capture system. (author)

  20. Two-Link Flexible Manipulator Control Using Sliding Mode Control Based Linear Matrix Inequality

    Science.gov (United States)

    Zulfatman; Marzuki, Mohammad; Alif Mardiyah, Nur

    2017-04-01

    Two-link flexible manipulator is a manipulator robot which at least one of its arms is made of lightweight material and not rigid. Flexible robot manipulator has some advantages over the rigid robot manipulator, such as lighter, requires less power and costs, and to result greater payload. However, suitable control algorithm to maintain the two-link flexible robot manipulator in accurate positioning is very challenging. In this study, sliding mode control (SMC) was employed as robust control algorithm due to its insensitivity on the system parameter variations and the presence of disturbances when the system states are sliding on a sliding surface. SMC algorithm was combined with linear matrix inequality (LMI), which aims to reduce the effects of chattering coming from the oscillation of the state during sliding on the sliding surface. Stability of the control algorithm is guaranteed by Lyapunov function candidate. Based on simulation works, SMC based LMI resulted in better performance improvements despite the disturbances with significant chattering reduction. This was evident from the decline of the sum of squared tracking error (SSTE) and the sum of squared of control input (SSCI) indexes respectively 25.4% and 19.4%.

  1. Kinematics study and workspace analysis of an articulated robotic arm of a rpar

    International Nuclear Information System (INIS)

    Zeb, J.; Rashid, F.; Iqbal, N.

    2007-01-01

    An itinerant RPAR (Radiation Protection Assistant Robot) has been constructed to assist radiation workers in radiation area which are radiologically hazardous and beyond tile safe approach of radiation workers. The RPAR comprises of a cubicle tri- wheeled platform and a 4-DOF (Four Degree of Freedom) serial type articulated robotic arm. The movement of the platform is controlled by two differential wheeled driving systems. The Kinematics and Manipulator Jacobian of the end-effector (gripper) of the articulated robotic arm mounted on the RPAR were evaluated. The work space analyses of the articulated robotic arm have been carried out. The RPAR is helpful for surveillance of radiation zones, to pick and carry dropdown radioactive samples and sources, in routine radiological operations as well as during an emergency response to a radiological accident. The performance of the RPAR was found satisfactory. (author)

  2. The Microsoft Visual Studio Software Development For 5 DOF Nuclear Malaysia Robot Arm V2 Control System

    International Nuclear Information System (INIS)

    Mohd Zaid Hassan; Anwar Abdul Rahman; Azraf Azman; Mohd Rizal Mamat; Mohd Arif Hamzah

    2014-01-01

    This paper presents the Microsoft visual studio development for 5DOF Nuclear Malaysia Robot Arm V2 control system. The kinematics analysis is the study of the relationship between the individual joints of robot manipulator, the position and orientation of the end-effector. The Denavit-Hartenberg (DH) model is used to model the robot links and joints. Both forward and inverse kinematic are presented. The simulation software has been developed by using Microsoft visual studio to solve the robot arms kinematic behavior. (author)

  3. Hydraulic turbines

    International Nuclear Information System (INIS)

    Meluk O, G.

    1998-01-01

    The hydraulic turbines are defined according to the specific speed, in impulse turbines and in reaction turbines. Currently, the Pelton turbines (of impulse) and the Francis and Kaplan turbines (of reaction), they are the most important machines in the hydroelectric generation. The hydraulic turbines are capable of generating in short times, large powers, from its loads zero until the total load and reject the load instantly without producing damages in the operation. When the hydraulic resources are important, the hydraulic turbines are converted in the axle of the electric system. Its combination with thermoelectric generation systems, it allow the continuing supply of the variations in demand of energy system. The available hydraulic resource in Colombia is of 93085 MW, of which solely 9% is exploited, become 79% of all the electrical country generation, 21% remaining is provided by means of the thermoelectric generation

  4. Performance evaluation of 3D vision-based semi-autonomous control method for assistive robotic manipulator.

    Science.gov (United States)

    Ka, Hyun W; Chung, Cheng-Shiu; Ding, Dan; James, Khara; Cooper, Rory

    2018-02-01

    We developed a 3D vision-based semi-autonomous control interface for assistive robotic manipulators. It was implemented based on one of the most popular commercially available assistive robotic manipulator combined with a low-cost depth-sensing camera mounted on the robot base. To perform a manipulation task with the 3D vision-based semi-autonomous control interface, a user starts operating with a manual control method available to him/her. When detecting objects within a set range, the control interface automatically stops the robot, and provides the user with possible manipulation options through audible text output, based on the detected object characteristics. Then, the system waits until the user states a voice command. Once the user command is given, the control interface drives the robot autonomously until the given command is completed. In the empirical evaluations conducted with human subjects from two different groups, it was shown that the semi-autonomous control can be used as an alternative control method to enable individuals with impaired motor control to more efficiently operate the robot arms by facilitating their fine motion control. The advantage of semi-autonomous control was not so obvious for the simple tasks. But, for the relatively complex real-life tasks, the 3D vision-based semi-autonomous control showed significantly faster performance. Implications for Rehabilitation A 3D vision-based semi-autonomous control interface will improve clinical practice by providing an alternative control method that is less demanding physically as well cognitively. A 3D vision-based semi-autonomous control provides the user with task specific intelligent semiautonomous manipulation assistances. A 3D vision-based semi-autonomous control gives the user the feeling that he or she is still in control at any moment. A 3D vision-based semi-autonomous control is compatible with different types of new and existing manual control methods for ARMs.

  5. Electro-active bio-films: formation, characterization and mechanisms

    International Nuclear Information System (INIS)

    Parot, Sandrine

    2007-01-01

    Some bacteria, which are able to exchange electrons with a conductive material without mediator form on conductive surfaces electro-active bio-films. This bacterial property has been recently discovered (2001). Objectives of this work are to develop electro-active bio-films in various natural environments from indigenous flora, then through complementary electrochemical techniques (chrono-amperometry and cyclic voltammetry), to evaluate electro-activity of isolates coming from so-formed bio-films and to characterize mechanisms of electron transfer between bacteria and materials. First, electro-active bio-films have been developed under chrono-amperometry in garden compost and in water coming from Guyana mangrove. These bio-films were respectively able to use an electrode as electron acceptor (oxidation) or as electron donor (reduction). In compost, results obtained in chrono-amperometry and cyclic voltammetry suggest a two-step electron transfer: slow substrate consumption, then rapid electron transfer between bacteria and the electrode. Thereafter, the ability to reduce oxygen was demonstrated with cyclic voltammetry for facultative aerobic isolates from compost bio-films (Enterobacter spp. and Pseudomonas spp.) and for aerobic isolates obtained from marine electro-active bio-films (Roseobacter spp. in majority). Finally, bio-films inducing current increase in chrono-amperometry were developed in bioreactor with synthetic medium from a pure culture of isolates. Hence, for the first time, electro-activity of several anaerobic strains of Geobacter bremensis isolated from compost bio-films was highlighted. (author) [fr

  6. An adaptive inverse kinematics algorithm for robot manipulators

    Science.gov (United States)

    Colbaugh, R.; Glass, K.; Seraji, H.

    1990-01-01

    An adaptive algorithm for solving the inverse kinematics problem for robot manipulators is presented. The algorithm is derived using model reference adaptive control (MRAC) theory and is computationally efficient for online applications. The scheme requires no a priori knowledge of the kinematics of the robot if Cartesian end-effector sensing is available, and it requires knowledge of only the forward kinematics if joint position sensing is used. Computer simulation results are given for the redundant seven-DOF robotics research arm, demonstrating that the proposed algorithm yields accurate joint angle trajectories for a given end-effector position/orientation trajectory.

  7. On-line trajectory planning of time-jerk optimal for robotic arms

    Directory of Open Access Journals (Sweden)

    Nadir Bendali

    2016-09-01

    Full Text Available A method based on the computation of the time intervals of the knots for time-jerk optimal planning under kinematic constraints of robot manipulators in predefined operations is described in this paper. In order to ensure that the resulting trajectory is smooth enough, a cost function containing a term proportional to the integral of the squared jerk (defined as the derivative of the acceleration along the trajectory is considered. Moreover, a second term, proportional to the total execution time, is added to the expression of the cost function. A Cubic Spline functions are then used to compose overall trajectory. This method can meet the requirements of a short execution time and low arm vibration of the manipulator and the simulation provides good results.

  8. Optimization of potential field method parameters through networks for swarm cooperative manipulation tasks

    Directory of Open Access Journals (Sweden)

    Rocco Furferi

    2016-10-01

    Full Text Available An interesting current research field related to autonomous robots is mobile manipulation performed by cooperating robots (in terrestrial, aerial and underwater environments. Focusing on the underwater scenario, cooperative manipulation of Intervention-Autonomous Underwater Vehicles (I-AUVs is a complex and difficult application compared with the terrestrial or aerial ones because of many technical issues, such as underwater localization and limited communication. A decentralized approach for cooperative mobile manipulation of I-AUVs based on Artificial Neural Networks (ANNs is proposed in this article. This strategy exploits the potential field method; a multi-layer control structure is developed to manage the coordination of the swarm, the guidance and navigation of I-AUVs and the manipulation task. In the article, this new strategy has been implemented in the simulation environment, simulating the transportation of an object. This object is moved along a desired trajectory in an unknown environment and it is transported by four underwater mobile robots, each one provided with a seven-degrees-of-freedom robotic arm. The simulation results are optimized thanks to the ANNs used for the potentials tuning.

  9. Electro-chemical grinding

    Science.gov (United States)

    Feagans, P. L.

    1972-01-01

    Electro-chemical grinding technique has rotation speed control, constant feed rates, and contour control. Hypersonic engine parts of nickel alloys can be almost 100% machined, keeping tool pressure at virtual zero. Technique eliminates galling and permits constant surface finish and burr-free interrupted cutting.

  10. A study on optimal motion for a robot manipulator amid obstacles

    International Nuclear Information System (INIS)

    Park, Jong Keun

    1997-01-01

    Optimal motion for a robot manipulator is obtained by nonlinear programming. The objective of optimal motion is minimizing energy consumption of manipulator arm with fixed traveling time in the presence of obstacles. The geometric path is not predetermined. The total trajectory is described in terms of cubic B-spline polynomials and the coefficients of them are obtained to minimize a specific performance index. Obstacle avoidance is performed by the method that the square sum of penetration growth distances between every obstacles and robot links is included in the performance index with appropriate weighting coefficient. In all examples tested here, the solutions were converged to unique optimal trajectories from different initial ones. The optimal geometric path obtained in this research can be used in minimum time trajectory planning. (author)

  11. Turbogas control unit using a hydraulic interface; Control de una unidad turbogas usando una interfase hidraulica

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez Palacios, Ignacio Ramon; Castelo Cuevas, Luis [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: irrp@iie.org.mx; lcastelo@iie.org.mx; Escarcega Navarrete, Luis [Servi-Control Monterrey S.A. de C.V., Monterrey, Nuevo Leon (Mexico)]. E-mail: lescarcega@servicontrol.com

    2010-11-15

    This paper presents the design and implementation of the control system of the Turbo Generator Unit (TGU) GE 5001, placed in Laguna Chavez power generation facility in Gomez Palacio, Dgo., Mexico. This TGU had been operating with an old control system, back to the 70's. The positioning of the control valves was carried out using a complex electro-hydraulic system. For the modernization of the control system, we use latest PLC technology and a current to pressure converter to communicate the PLC with the hydraulic control valves. The new control system helped us to obtain a best response at the start and generation phases, as well as an increase in the availability of the unit. We show the old and the new control architectures besides plot results obtained at the different operation points. [Spanish] En este articulo se presenta la implementacion y diseno del sistema de control de una Unidad Turbogas (UTG) GE-5001 de la Central Turbogas Laguna Chavez de CFE ubicada en Gomez Palacio, Durango, la cual originalmente era controlada mediante un sistema de control con tecnologia de los anos 70's. El posicionamiento de las valvulas de control se realizaba mediante un sistema electro-hidraulico complejo. Para la modernizacion del sistema de control a uno con tecnologia de punta fue necesario utilizar una interfase hidraulica por medio de un convertidor de corriente/presion (I/P) para el posicionamiento de las valvulas originales. Con la modernizacion se mejoro la respuesta del control asi como el incremento de la disponibilidad de la unidad. Se presentan la arquitectura anterior y actual de sistema de control asi como graficas de los resultados obtenidos en diferentes puntos de operacion de la UTG.

  12. Controlling Flexible Robot Arms Using High Speed Dynamics Process

    Science.gov (United States)

    Jain, Abhinandan (Inventor)

    1996-01-01

    A robot manipulator controller for a flexible manipulator arm having plural bodies connected at respective movable hinges and flexible in plural deformation modes corresponding to respective modal spatial influence vectors relating deformations of plural spaced nodes of respective bodies to the plural deformation modes, operates by computing articulated body quantities for each of the bodies from respective modal spatial influence vectors, obtaining specified body forces for each of the bodies, and computing modal deformation accelerations of the nodes and hinge accelerations of the hinges from the specified body forces, from the articulated body quantities and from the modal spatial influence vectors. In one embodiment of the invention, the controller further operates by comparing the accelerations thus computed to desired manipulator motion to determine a motion discrepancy, and correcting the specified body forces so as to reduce the motion discrepancy. The manipulator bodies and hinges are characterized by respective vectors of deformation and hinge configuration variables, and computing modal deformation accelerations and hinge accelerations is carried out for each one of the bodies beginning with the outermost body by computing a residual body force from a residual body force of a previous body and from the vector of deformation and hinge configuration variables, computing a resultant hinge acceleration from the body force, the residual body force and the articulated hinge inertia, and revising the residual body force modal body acceleration.

  13. Development of a mobile manipulator for nuclear plant disaster, HELIOS X. Mechanical design and basic experiments

    International Nuclear Information System (INIS)

    Noda, Satsuya; Hirose, Shigeo; Ueda, Koji; Nakano, Hisami; Horigome, Atsushi; Endo, Gen

    2016-01-01

    In places such as nuclear power plant disaster area, which it is difficult for human workers to enter, robots are required to scout those places instead of human workers. In this paper, we present a mobile manipulator HELIOS X for a nuclear plant decommissioning task. Firstly, we address demands and specifications for the robot, considering the mission of reconnaissance. Then we outline the system of the robot, mainly focusing on the following mechanism: 'Crank Wheel', 'Main Arm', 'Sphere Link Wrist', 'Camera Arm', 'Control System' and 'System architecture'. Especially, we installed 3 degree of freedom 'Camera Arm' on the 'Main Arm', in order to improve functionality of remote control system. This enables the operator to monitor both the gripper and its overall view of the robot. 'Camera Arm' helps the operator to recognize the distance from an object to the gripper, because the operator can interactively move the viewpoint of the camera, and monitor from another camera angle without changing the gripper's position. We confirmed the basic functionality of mobile base, 'Main Arm' and 'Camera Arm' through hardware experiments. We also demonstrated that HELIOS X could pass through the pull-to-open door with a substantial closing force when the operator watched camera view only. (author)

  14. A world first. Industrial operation of computer-aided master-slave manipulator at the La Hague recycling plant

    International Nuclear Information System (INIS)

    Brueziere, Jerome; Thro, Jean Francois; Brudieu, Marie-Anne; Piolain, Gerard; Geffard, Franck; Garrec, Philippe; Measson, Yvan; Coudray, Alain; Lelann, Eric

    2011-01-01

    Since the beginning of industrial nuclear plants like recycling, mechanical master-slave manipulators have been widely used for operation and maintenance in hot cells, in conjunction with shielding windows. In the La Hague plant for instance, all hot cells where maintenance is or could be required are fitted with shielding windows and through-wall telescopic master-slave manipulators. This well mastered solution, if used by highly skilled workers, has demonstrated its capability to perform all the maintenance tasks required, as long as equipment and tools inside the cell were designed accordingly. However, this technology has also shown significant limitations in terms of capacity, flexibility, efficiency and reliability. In order to improve those characteristics, AREVA and CEA have developed together a new technology: computer-aided master-slave manipulators. By replacing the traditional mechanical link, between the 'slave arm' in the cell and the 'master arm', with motors, sensors and electronics, this new tool improves load capacity and provides added flexibility and efficiency, while protecting the slave arm from overload and therefore improving reliability. In addition, this new device was developed to be fully compatible with current La Hague configuration. After developing and testing this solution in realistic but inactive environment, by performing all kinds of operation and maintenance activities with trained workers, the first generation tool was improved by incorporating feed-back and suggestions from operators. Second generation system was then developed, and first introduced in 2010 in an active cell of the La Hague plant, namely a vitrification cell. After a few months in operation, feedback from manufacturing staff was so positive that implementation of several new arms was decided for 2011. This paper will describe how this development benefited from the existing know-how and component library jointly developed by AREVA and CEA, as well as the main

  15. Hydraulic design of Three Gorges right bank powerhouse turbine for improvement of hydraulic stability

    International Nuclear Information System (INIS)

    Shi, Q

    2010-01-01

    This paper presents the hydraulic design of Three Gorges Right Bank Powerhouse turbine for improvement of hydraulic stability. The technical challenges faced in the hydraulic design of the turbine are given. The method of hydraulic design for improving the hydraulic stability and particularly for eliminating the upper part load pressure pulsations is clarified. The final hydraulic design results of Three Gorges Right Bank Powerhouse turbine based on modern hydraulic design techniques are presented.

  16. Hydraulic design of Three Gorges right bank powerhouse turbine for improvement of hydraulic stability

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Q, E-mail: qhshi@dfem.com.c [Dong Fang Electrical Machinery Co., Ltd., DEC 188, Huanghe West Road, Deyang, 618000 (China)

    2010-08-15

    This paper presents the hydraulic design of Three Gorges Right Bank Powerhouse turbine for improvement of hydraulic stability. The technical challenges faced in the hydraulic design of the turbine are given. The method of hydraulic design for improving the hydraulic stability and particularly for eliminating the upper part load pressure pulsations is clarified. The final hydraulic design results of Three Gorges Right Bank Powerhouse turbine based on modern hydraulic design techniques are presented.

  17. Theory-inspired development of organic electro-optic materials

    Energy Technology Data Exchange (ETDEWEB)

    Dalton, Larry R., E-mail: dalton@chem.washington.ed [Department of Chemistry, Bagley Hall 202D, Box 351700, University of Washington, Seattle, Washington 98195-1700 (United States); Department of Electrical Engineering, Bagley Hall 202D, Box 351700, University of Washington, Seattle, Washington 98195-1700 (United States)

    2009-11-30

    Real-time, time-dependent density functional theory (RTTDDFT) and pseudo-atomistic Monte Carlo-molecular dynamics (PAMCMD) calculations have been used in a correlated manner to achieve quantitative definition of structure/function relationships necessary for the optimization of electro-optic activity in organic materials. Utilizing theoretical guidance, electro-optic coefficients (at telecommunication wavelengths) have been increased to 500 pm/V while keeping optical loss to less than 2 dB/cm. RTTDDFT affords the advantage of permitting explicit treatment of time-dependent electric fields, both applied fields and internal fields. This modification has permitted the quantitative simulation of the variation of linear and nonlinear optical properties of chromophores and the electro-optic activity of materials with optical frequency and dielectric permittivity. PAMCMD statistical mechanical calculations have proven an effective means of treating the full range of spatially-anisotropic intermolecular electrostatic interactions that play critical roles in defining the degree of noncentrosymmetric order that is achieved by electric field poling of organic electro-optic materials near their glass transition temperatures. New techniques have been developed for the experimental characterization of poling-induced acentric order including a modification of variable angle polarization absorption spectroscopy (VAPAS) permitting a meaningful correlation of theoretical and experimental data related to poling-induced order for a variety of complex organic electro-optic materials.

  18. Theory-inspired development of organic electro-optic materials

    International Nuclear Information System (INIS)

    Dalton, Larry R.

    2009-01-01

    Real-time, time-dependent density functional theory (RTTDDFT) and pseudo-atomistic Monte Carlo-molecular dynamics (PAMCMD) calculations have been used in a correlated manner to achieve quantitative definition of structure/function relationships necessary for the optimization of electro-optic activity in organic materials. Utilizing theoretical guidance, electro-optic coefficients (at telecommunication wavelengths) have been increased to 500 pm/V while keeping optical loss to less than 2 dB/cm. RTTDDFT affords the advantage of permitting explicit treatment of time-dependent electric fields, both applied fields and internal fields. This modification has permitted the quantitative simulation of the variation of linear and nonlinear optical properties of chromophores and the electro-optic activity of materials with optical frequency and dielectric permittivity. PAMCMD statistical mechanical calculations have proven an effective means of treating the full range of spatially-anisotropic intermolecular electrostatic interactions that play critical roles in defining the degree of noncentrosymmetric order that is achieved by electric field poling of organic electro-optic materials near their glass transition temperatures. New techniques have been developed for the experimental characterization of poling-induced acentric order including a modification of variable angle polarization absorption spectroscopy (VAPAS) permitting a meaningful correlation of theoretical and experimental data related to poling-induced order for a variety of complex organic electro-optic materials.

  19. Electro/powder separation process

    International Nuclear Information System (INIS)

    Dunn, J.P.

    1977-01-01

    A report is presented to introduce the ELECTRO/POWDER process to the P/M Industry. The process effectively uses electrostatic forces to convey, sort, meter, and blend fine powders. The major advantages of this separating process consist of the processing of primary particles, low particle energy due to particle velocity control and the pattern of particle movement over the sieve (vertical oscillation of particles above the sieve aperture). The report briefly describes the forces involved in both mechanical and sieving devices, with major emphasis on the operating principles of this process. Sieve separation of particulates is basically the result of two physical separating processes which occur simultaneously or independently; separation (dispersion) of particulates from each other and the size separation by passage through fixed apertures. In order to accomplish this goal, mechanical sieving devices utilize various motions to induce shear forces between the sieve surface and the particulates, and between the particulates themselves. It is noted that the ELECTRO/POWDER process is making steady progress in becoming an industrial tool for sieving and feeding of fine particles. Its potential extends into both the blending and admixing of powders, either by incorporating two opposing feeders, one being charged with the opposite polarity or by modifying the ELECTRO/SIEVE to incorporate more than one input and a solid electrode to replace the sieve electrode

  20. Research on Trajectory Planning and Autodig of Hydraulic Excavator

    Directory of Open Access Journals (Sweden)

    Bin Zhang

    2017-01-01

    Full Text Available As the advances in computer control technology keep emerging, robotic hydraulic excavator becomes imperative. It can improve excavation accuracy and greatly reduce the operator’s labor intensity. The 12-ton backhoe bucket excavator has been utilized in this research work where this type of excavator is commonly used in engineering work. The kinematics model of operation device (boom, arm, bucket, and swing in excavator is established in both Denavit-Hartenberg coordinates for easy programming and geometric space for avoiding blind spot. The control approach is based on trajectory tracing method with displacements and velocities feedbacks. The trajectory planning and autodig program is written by Visual C++. By setting the bucket teeth’s trajectory, the program can automatically plan the velocity and acceleration of each hydraulic cylinder and motor. The results are displayed through a 3D entity simulation environment which can present real-time movements of excavator kinematics. Object-Oriented Graphics Rendering Engine and skeletal animation are used to give accurate parametric control and feedback. The simulation result shows that a stable linear autodig can be achieved. The errors between trajectory planning command and simulation model are analyzed.

  1. Innovation on structure of all automatic multi-studs four synchronous installing machine used in PWR

    International Nuclear Information System (INIS)

    Zhu Qirong; Zou Xiyang

    2002-01-01

    First of all from structure bring forth many new ideas. New stud, nut and a brand-new installing machine have been designed. In main machine, the integrated gear mechanism simple in structure achieves synchronous turning function, instead of the precision, complicated, expensive manipulator or robot. In aspect of supervising and controlling, computer electro-hydraulic proportional control and advanced examine measure system have been designed to measure stress and extension of stud as tensioning. Mathematics model and transmit function have been built using theory of modern times fluid transmission and control. As a result four synchronous installing has been achieved

  2. Modelling electro-active polymers with a dispersion-type anisotropy

    Science.gov (United States)

    Hossain, Mokarram; Steinmann, Paul

    2018-02-01

    We propose a novel constitutive framework for electro-active polymers (EAPs) that can take into account anisotropy with a chain dispersion. To enhance actuation behaviour, particle-filled EAPs become promising candidates nowadays. Recent studies suggest that particle-filled EAPs, which can be cured under an electric field during the manufacturing time, do not necessarily form perfect anisotropic composites, rather they create composites with dispersed chains. Hence in this contribution, an electro-mechanically coupled constitutive model is devised that considers the chain dispersion with a probability distribution function in an integral form. To obtain relevant quantities in discrete form, numerical integration over the unit sphere is utilized. Necessary constitutive equations are derived exploiting the basic laws of thermodynamics that result in a thermodynamically consistent formulation. To demonstrate the performance of the proposed electro-mechanically coupled framework, we analytically solve a non-homogeneous boundary value problem, the extension and inflation of an axisymmetric cylindrical tube under electro-mechanically coupled load. The results capture various electro-mechanical couplings with the formulation proposed for EAP composites.

  3. Drying brick masonry by electro-osmosis

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Rörig-Dalgaard, Inge

    2006-01-01

    When a fine grained, porous medium is applied an electric DC field, transport of matter occurs, and the transport mechanism in focus of the present study is electro-osmosis, which is transport of water. In laboratory it was shown possible to transport water inside a brick and brick/mortar system...... movement of water towards the cathode was seen. Thus the basis for utilizing the electro-osmotic effect for drying brick masonry is present, but proper electrodes still needs to be developed....

  4. A variable geometry truss manipulator for positioning large payloads

    International Nuclear Information System (INIS)

    Stoughton, R.S.; Tucker, J.C.; Horner, C.G.

    1995-02-01

    A major thrust within the Department of Energy's (DOE) Decontamination and Dismantling (D ampersand D) Robotics program is the development of a Selective Equipment Removal System (SERS). SERS will consist of a mobile vehicle, a Dual-Arm Work Module (DAWM), and a deployment manipulator capable of extending the DAWM up to 6.096m (20) from the vehicle. The DAWM, built by RedZone Robotics, includes two Schilling Titan II manipulators, a unique five degree-of-freedom (DOF) module for positioning/orienting the two Schilling arms, and a massive steel backplane to maintain structural rigidity. Together with its payload, the DAWM weighs about 975 kg (2150 pounds). In order to accurately position the DAWM, the Pacific Northwest Laboratory (PNL) together with the National Aeronautics and Space Administration's Langley Research Center (NASA LARC) are developing a deployment manipulator, which includes two double-octahedral Variable Geometry Truss (VGT) modules connected with a static truss section. The entire SERS system (Figure 1) will include the mobile vehicle, a 2-DOF base actuation system (waist rotate and pitch) with an output link approximately 2.134m (7) in length, the VGT system and the DAWM. The VGT system (Figure 2) consists of a 1.067m (42) diameter (∼1.346m (53) long) base VGT, which mounts to the end of the output link of the base actuation system, a 1.524m (60) long static truss section which tapers from 1.067m (42) diameter at its base to 0.8128m (32) diameter at the end, and a 0.8128m (32) diameter (∼1.0922m (43) long) tip VGT to which the DAWM is mounted. The stiffness of the VGT system is such that with the base VGT mounted to a rigid base and the VGT system oriented horizontally (worst case), the static deflection of the DAWM together with full payload will be less than 0.0254m

  5. Inertial measurement unit–based iterative pose compensation algorithm for low-cost modular manipulator

    Directory of Open Access Journals (Sweden)

    Yunhan Lin

    2016-01-01

    Full Text Available It is a necessary mean to realize the accurate motion control of the manipulator which uses end-effector pose correction method and compensation method. In this article, first, we established the kinematic model and error model of the modular manipulator (WUST-ARM, and then we discussed the measurement methods and precision of the inertial measurement unit sensor. The inertial measurement unit sensor is mounted on the end-effector of modular manipulator, to get the real-time pose of the end-effector. At last, a new inertial measurement unit–based iterative pose compensation algorithm is proposed. By applying this algorithm in the pose compensation experiment of modular manipulator which is composed of low-cost rotation joints, the results show that the inertial measurement unit can obtain a higher precision when in static state; it will accurately feedback to the control system with an accurate error compensation angle after a brief delay when the end-effector moves to the target point, and after compensation, the precision errors of roll angle, pitch angle, and yaw angle are reached at 0.05°, 0.01°, and 0.27° respectively. It proves that this low-cost method provides a new solution to improve the end-effector pose of low-cost modular manipulator.

  6. Genetic algorithm trajectory plan optimization for EAMA: EAST Articulated Maintenance Arm

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jing, E-mail: wujing@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, 350 Shushanhu Rd., Hefei, Anhui (China); Lappeenranta University of Technology, Skinnarilankatu 34, Lappeenranta (Finland); Wu, Huapeng [Lappeenranta University of Technology, Skinnarilankatu 34, Lappeenranta (Finland); Song, Yuntao; Cheng, Yong; Zhao, Wenglong [Institute of Plasma Physics, Chinese Academy of Sciences, 350 Shushanhu Rd., Hefei, Anhui (China); Wang, Yongbo [Lappeenranta University of Technology, Skinnarilankatu 34, Lappeenranta (Finland)

    2016-11-01

    Highlights: • A redundant 10-DOF serial-articulated robot for EAST assembly and maintains is presented. • A trajectory optimization algorithm of the robot is developed. • A minimum jerk objective is presented to suppress machining vibration of the robot. - Abstract: EAMA (EAST Articulated Maintenance Arm) is an articulated serial manipulator with 7 degrees of freedom (DOF) articulated arm followed by 3-DOF gripper, total length is 8.867 m, works in experimental advanced superconductor tokamak (EAST) vacuum vessel (VV) to perform blanket inspection and remote maintenance tasks. This paper presents a trajectory optimization method which aims to pursue the 7-DOF articulated arm a stable movement, which keeps the mounted inspection camera anti-vibration. Based on dynamics analysis, trajectory optimization algorithm adopts multi-order polynomial interpolation in joint space and high order geometry Jacobian transform. The object of optimization algorithm is to suppress end-effector movement vibration by minimizing jerk RMS (root mean square) value. The proposed solution has such characteristics which can satisfy kinematic constraints of EAMA’s motion and ensure the arm running under the absolute values of velocity, acceleration and jerk boundaries. GA (genetic algorithm) is employed to find global and robust solution for this problem.

  7. Hierarchical control system of advanced robot manipulator

    International Nuclear Information System (INIS)

    Oomichi, Takeo; Okino, Akihisa; Nishihara, Masatoshi; Sakamoto, Taizou; Matsuda, Koichi; Ohnishi, Ken

    1990-01-01

    We introduce a double arm with 4-finger's manipulator system which process the large volume of information at high speed. This is under research/development many type of works in the harsh condition. Namely, hierarchization of instruction unit in which motion control system as real time processing unit, and task planning unit as non-real time processing unit, interface with operation through the task planning unit has been made. Also, high speed processing of large volume information has been realized by decentralizing the motion control unit by function, hierarchizing the high speed processing unit, and developing high speed transmission, IC which does not depend on computer OS to avoid the delay in transmission. (author)

  8. Compliant electro-thermal microactuators

    DEFF Research Database (Denmark)

    Jonsmann, Jacques; Sigmund, Ole; Bouwstra, Siebe

    1999-01-01

    This paper describes design, microfabrication and characterisation of topology optimised compliant electro-thermal microactuators. The actuators are fabricated by a fast prototyping process using laser micromachining and electroplating. Actuators are characterised with respect to displacement...

  9. Rational design of organic electro-optic materials

    CERN Document Server

    Dalton, L R

    2003-01-01

    Quantum mechanical calculations are used to optimize the molecular first hyperpolarizability of organic chromophores and statistical mechanical calculations are used to optimize the translation of molecular hyperpolarizability to macroscopic electro-optic activity (to values of greater than 100 pm V sup - sup 1 at telecommunications wavelengths). Macroscopic material architectures are implemented exploiting new concepts in nanoscale architectural engineering. Multi-chromophore-containing dendrimers and dendronized polymers not only permit optimization of electro-optic activity but also of auxiliary properties including optical loss (both absorption and scattering), thermal and photochemical stability and processability. New reactive ion etching and photolithographic techniques permit the fabrication of three-dimensional optical circuitry and the integration of that circuitry with semiconductor very-large-scale integration electronics and silica fibre optics. Electro-optic devices have been fabricated exploiti...

  10. Summary report on development of bilateral servo manipulator (BSM) for nuclear fuel cycle facilities in the Japan Nuclear Cycle Development Institute

    International Nuclear Information System (INIS)

    Miki, Yasuo; Koizumi, Tsutomu; Aoshima, Atsushi; Kawanobe, Kazunori; Kobayashi, Yuichi

    2000-03-01

    In order to improve availability of nuclear fuel cycle facilities such as fuel reprocessing plants, reduce occupational radiation exposure, the Japan Nuclear Cycle Development Institute (JNC) has been developing an advanced remote manipulative system for fully remote maintenance and repair tasks in large volume repair cells. Fully remote maintenance and repair task is performed primarily by the utilization of overhead bridge cranes, mechanical master-slave manipulators and electro-mechanical power manipulators. This system requires also that plant process and remote processing equipment should be designed to provide modular or unit replacement based on the potential mode of system failures. Repair of equipment is performed following removal of the failed component from process line and transfer to the repair cell. Equipment repair in the cell is commonly carried out by the use of remote manipulators. However, the realization of fully remote maintenance facility requires so remote manipulative systems as to provide excellent controllability, durability and remote maintenance capability, development of a bilateral servo-manipulator was initiated in 1982. Two of BSM were installed in the Tokai Vitrification Facility (TVF) cell and their remote maintenance feasibility was evaluated. Following installation in the TVF, developing efforts toward achieving advanced remote maintenance capability for the Recycle Equipment Test Facility (RETF) have been made. This report summarizes mainly mechanical and control system design for improvement, particularly upgrading controllability. (Itami, H.)

  11. Replacement of pneumatic and hydraulic drives with electrical drives - Analysis of potential; Ersatz von pneumatischen und hydraulischen Antrieben durch Elektroantriebe. Potentialanalyse

    Energy Technology Data Exchange (ETDEWEB)

    Berchten, S. [BEngineering, Bassersdorf (Switzerland); Ritz, Ch. [Schnyder Ingenieure AG, Steg (Switzerland)

    2006-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) discusses the potential offered by modern technologies to save energy. The replacement of energy-intensive methods of providing physical movement - such as with pneumatic and hydraulic drives - with electrical drives is discussed. Based on existing installations in industry, an estimate of the potential for making savings is presented. This shows that large energy savings can be made by directly converting electrical into mechanical energy. Using real world examples, end-users and decision-makers are shown two profit-scenarios involving the purchase of a new system or retrofitting an existing system. The scenarios take investments, operating costs and system life-cycle into account. Extrapolations provide estimates of savings-potentials for the Swiss electricity market. Various market sectors are looked at, including the metal-working, chemical, foodstuffs and packaging sectors. Examples of installations actually implemented, where electro-mechanical systems have replaced pneumatic and hydraulic drives, are given.

  12. Thermally Actuated Hydraulic Pumps

    Science.gov (United States)

    Jones, Jack; Ross, Ronald; Chao, Yi

    2008-01-01

    Thermally actuated hydraulic pumps have been proposed for diverse applications in which direct electrical or mechanical actuation is undesirable and the relative slowness of thermal actuation can be tolerated. The proposed pumps would not contain any sliding (wearing) parts in their compressors and, hence, could have long operational lifetimes. The basic principle of a pump according to the proposal is to utilize the thermal expansion and contraction of a wax or other phase-change material in contact with a hydraulic fluid in a rigid chamber. Heating the chamber and its contents from below to above the melting temperature of the phase-change material would cause the material to expand significantly, thus causing a substantial increase in hydraulic pressure and/or a substantial displacement of hydraulic fluid out of the chamber. Similarly, cooling the chamber and its contents from above to below the melting temperature of the phase-change material would cause the material to contract significantly, thus causing a substantial decrease in hydraulic pressure and/or a substantial displacement of hydraulic fluid into the chamber. The displacement of the hydraulic fluid could be used to drive a piston. The figure illustrates a simple example of a hydraulic jack driven by a thermally actuated hydraulic pump. The pump chamber would be a cylinder containing encapsulated wax pellets and containing radial fins to facilitate transfer of heat to and from the wax. The plastic encapsulation would serve as an oil/wax barrier and the remaining interior space could be filled with hydraulic oil. A filter would retain the encapsulated wax particles in the pump chamber while allowing the hydraulic oil to flow into and out of the chamber. In one important class of potential applications, thermally actuated hydraulic pumps, exploiting vertical ocean temperature gradients for heating and cooling as needed, would be used to vary hydraulic pressures to control buoyancy in undersea research

  13. JACoW A dual arms robotic platform control for navigation, inspection and telemanipulation

    CERN Document Server

    Di Castro, Mario; Ferre, Manuel; Gilardoni, Simone; Losito, Roberto; Lunghi, Giacomo; Masi, Alessandro

    2018-01-01

    High intensity hadron colliders and fixed target experiments require an increasing amount of robotic tele-manipulation to prevent excessive exposure of maintenance personnel to the radioactive environment. Telemanipulation tasks are often required on old radioactive devices not conceived to be maintained and handled using standard industrial robotic solutions. Robotic platforms with a level of dexterity that often require the use of two robotic arms with a minimum of six degrees of freedom are instead needed for these purposes. In this paper, the control of a novel robust robotic platform able to host and to carry safely a dual robotic arm system is presented. The control of the arms is fully integrated with the vehicle control in order to guarantee simplicity to the operators during the realization of the robotic tasks. A novel high-level control architecture for the new robot is shown, as well as a novel low level safety layer for anti-collision and recovery scenarios. Preliminary results of the system comm...

  14. Magneto-optic and electro-optic modulators

    International Nuclear Information System (INIS)

    Hutchinson, D.P.; Ma, C.H.; Price, T.R.; Staats, P.A.; Sluis, K.L.V.

    1982-01-01

    An important aspect of the Faraday rotation diagnostic for tokamak plasma measurement has been the development of suitable polarization modulators for submillimeter wavelength. The problems are to obtain high optical transmission and fast modulation frequencies. In ORNL, the authors have developed both a magneto-optic and an electro-optic submillimeter-wave modulators. These devices have been operated at modulation frequency of approximately 100 kHz, and both have high transmission. The original magneto-optic modulator consists of a 3 mm thick by 1.4 cm diameter 2-111 ferrite disk mounted at the center of an air core coil. Recently, a new ferrite modulator has been tested, which allows a much higher modulation frequency than the original device. A laboratory set-up designed to simulate a plasma heterodyne interferometer/polarimeter experiment has been used to determine the modulator characteristics. A mechanical polarization rotor was used to simulate the rotation by plasma. The transmission of the ferrite disk was 80 % at a wavelength of 0.447 mm. The authors have also performed preliminary measurement on an electro-optic modulator first demonstrated by Fetterman at Lincoln Laboratory, U.S. This device is a classical electro-optic modulator using a cryogenically cooled (4.2 K) LiTaO 3 crystal. Experiments are underway to determine the electro-optic properties of the crystal over the temperature range from 4.2 K to 77 K and over the range of wavelength from 0.118 mm to 0.447 mm. (Wakatsuki, Y.)

  15. Integration of a Robotic Arm with the Surgical Assistant Workstation Software Framework

    OpenAIRE

    Young, J.; Elhawary, H.; Popovic, A.

    2012-01-01

    We have integrated the Philips Research robot arm with the Johns Hopkins University cisst library, an open-source platform for computerassisted surgical intervention. The development of a Matlab to C++ wrapper to abstract away servo-level details facilitates the rapid development of a component-based framework with “plug and play” features. This allows the user to easily exchange the robot with an alternative manipulator while maintaining the same overall functionality.

  16. Electro Spray Method for Flexible Display

    Science.gov (United States)

    2016-05-12

    AFRL-AFOSR-JP-TR-2016-0095 Electro Spray Method for Flexible Display Yukiharu Uraoka NARA INSTITUTE OF SCIENCE AND TECHNOLOGY Final Report 11/26/2016...DATES COVERED (From - To)  20 Mar 2013 to 19 May 2016 4. TITLE AND SUBTITLE Electro Spray Method for Flexible Display 5a.  CONTRACT NUMBER 5b.  GRANT...NUMBER FA2386-13-1-4024 5c.  PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S) Yukiharu Uraoka 5d.  PROJECT NUMBER 5e.  TASK NUMBER 5f.   WORK UNIT NUMBER 7

  17. Mine drivage in hydraulic mines

    Energy Technology Data Exchange (ETDEWEB)

    Ehkber, B Ya

    1983-09-01

    From 20 to 25% of labor cost in hydraulic coal mines falls on mine drivage. Range of mine drivage is high due to the large number of shortwalls mined by hydraulic monitors. Reducing mining cost in hydraulic mines depends on lowering drivage cost by use of new drivage systems or by increasing efficiency of drivage systems used at present. The following drivage methods used in hydraulic mines are compared: heading machines with hydraulic haulage of cut rocks and coal, hydraulic monitors with hydraulic haulage, drilling and blasting with hydraulic haulage of blasted rocks. Mining and geologic conditions which influence selection of the optimum mine drivage system are analyzed. Standardized cross sections of mine roadways driven by the 3 methods are shown in schemes. Support systems used in mine roadways are compared: timber supports, roof bolts, roof bolts with steel elements, and roadways driven in rocks without a support system. Heading machines (K-56MG, GPKG, 4PU, PK-3M) and hydraulic monitors (GMDTs-3M, 12GD-2) used for mine drivage are described. Data on mine drivage in hydraulic coal mines in the Kuzbass are discussed. From 40 to 46% of roadways are driven by heading machines with hydraulic haulage and from 12 to 15% by hydraulic monitors with hydraulic haulage.

  18. Basic hydraulics

    CERN Document Server

    Smith, P D

    1982-01-01

    BASIC Hydraulics aims to help students both to become proficient in the BASIC programming language by actually using the language in an important field of engineering and to use computing as a means of mastering the subject of hydraulics. The book begins with a summary of the technique of computing in BASIC together with comments and listing of the main commands and statements. Subsequent chapters introduce the fundamental concepts and appropriate governing equations. Topics covered include principles of fluid mechanics; flow in pipes, pipe networks and open channels; hydraulic machinery;

  19. Demonstration of Vibrational Braille Code Display Using Large Displacement Micro-Electro-Mechanical Systems Actuators

    Science.gov (United States)

    Watanabe, Junpei; Ishikawa, Hiroaki; Arouette, Xavier; Matsumoto, Yasuaki; Miki, Norihisa

    2012-06-01

    In this paper, we present a vibrational Braille code display with large-displacement micro-electro-mechanical systems (MEMS) actuator arrays. Tactile receptors are more sensitive to vibrational stimuli than to static ones. Therefore, when each cell of the Braille code vibrates at optimal frequencies, subjects can recognize the codes more efficiently. We fabricated a vibrational Braille code display that used actuators consisting of piezoelectric actuators and a hydraulic displacement amplification mechanism (HDAM) as cells. The HDAM that encapsulated incompressible liquids in microchambers with two flexible polymer membranes could amplify the displacement of the MEMS actuator. We investigated the voltage required for subjects to recognize Braille codes when each cell, i.e., the large-displacement MEMS actuator, vibrated at various frequencies. Lower voltages were required at vibration frequencies higher than 50 Hz than at vibration frequencies lower than 50 Hz, which verified that the proposed vibrational Braille code display is efficient by successfully exploiting the characteristics of human tactile receptors.

  20. Electro-Optical Laser Technology. Curriculum Utilization. Final Report.

    Science.gov (United States)

    Nawn, John H.

    This report describes a program to prepare students for employment as laser technicians and laser operators and to ensure that they have the necessary skills required by the industry. The objectives are to prepare a curriculum and syllabus for an associate degree program in Electro-Optical Laser Technology. The 2-year Electro-Optical Laser program…

  1. Bioactivity of cellulose acetate/hydroxyapatite nanoparticle composite fiber by an electro-spinning process.

    Science.gov (United States)

    Kwak, Dae Hyun; Lee, Eun Ju; Kim, Deug Joong

    2014-11-01

    Hydroxyapatite/cellulose acetate composite webs were fabricated by an electro-spinning process. This electro-spinning process makes it possible to fabricate complex three-dimensional shapes. Nano fibrous web consisting of cellulose acetate and hydroxyapatite was produced from their mixture solution by using an electro-spinning process under high voltage. The surface of the electro-spun fiber was modified by a plasma and alkaline solution in order to increase its bioactivity. The structure, morphology and properties of the electro-spun fibers were investigated and an in-vitro bioactivity test was evaluated in simulated body fluid (SBF). Bioactivity of the electro-spun web was enhanced with the filler concentration and surface treatment. The surface changes of electro-spun fibers modified by plasma and alkaline solution were investigated by FT-IR (Fourier Transform Infrared Spectroscopy) and XPS (X-ray Photoelectron Spectroscopy).

  2. Development and performance tests of the bridge-transported servo manipulator system for remote maintenance jobs in a hot cell

    International Nuclear Information System (INIS)

    Jin, Jae Hyun; Park, Byung Suk; Ko, Byung Seung; Yoon, Ji Sup; Jung, Ki Jung

    2005-01-01

    In this paper, a prototype of the Bridge-Transported Servo Manipulator (BTSM) system introduced, which has been developed to do operation and maintenance jobs remotely in a hot cell. The system consists of a telescopic transporter, a slave arm, a master arm, and a control system. Several tests such as a positional tracking, a weight handling, reliability, and operability have been performed and test results are presented. Based on the test results, an upgraded system which will be used during demonstrations of the advanced spent fuel conditioning process (ACP) has been designed.

  3. Electro-Optics/Low Observables Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Electro-Optics/Low Observables Laboratory supports graduate instruction for students enrolled in the Low Observables program. Its purpose is to introduce these...

  4. Bifunctional Pt-Si Alloys for Small Organic Molecule Electro-oxidation

    DEFF Research Database (Denmark)

    Permyakova, Anastasia Aleksandrovna; Suntivich, Jin; Han, Binghong

    Designing highly active catalysts for electro-oxidation of small organic molecules can help to reduce the anodic overpotential for more efficient utilization of hydrocarbon fuels. The challenge in developing more active electrocatalysts for electro-oxidation reactions is to satisfy the stringent...... adsorption site. We will discuss the enhanced activity of Pt-Si alloys for small organic molecule oxidation, which can be attributed to the improved CO electro-oxidation kinetics on Pt-Si....

  5. Electro-osmotic flows inside triangular microchannels

    International Nuclear Information System (INIS)

    Vocale, P; Spiga, M; Geri, M; Morini, G L

    2014-01-01

    This work presents a numerical investigation of both pure electro-osmotic and combined electro-osmotic/pressure-driven flows inside triangular microchannels. A finite element analysis has been adopted to solve the governing equations for the electric potential and the velocity field, accounting for a finite thickness of the electric double layer. The influence of non-dimensional parameters such as the aspect ratio of the cross-section, the electrokinetic diameter and the ratio of the pressure force to the electric force on the flow behavior has been investigated. Numerical results point out that the velocity field is significantly influenced by the aspect ratio of the cross section and the electrokinetic diameter. More specifically, the aspect ratio plays an important role in determining the maximum volumetric flow rate, while the electrokinetic diameter is crucial to establishing the range of pressures that may be sustained by the electro-osmotic flow. Numerical results are also compared with two correlations available in the literature which enable to assess the volumetric flow rate and the pressure head for microchannels featuring a rectangular, a trapezoidal or an elliptical cross-section.

  6. Sensor-based whole-arm obstacle avoidance utilizing ASIC technology

    International Nuclear Information System (INIS)

    Wintenberg, A.L.; Ericson, M.N.; Babcock, S.M.; Armstrong, G.A.; Britton, C.L. Jr.; Butler, P.L.; Hamel, W.R.; Newport, D.F.

    1993-01-01

    Operation of manipulator systems in poorly defined work environments often presents a significant hazard to both the robotic assembly and the environment. In applications relating to the Environmental Restoration and Waste Management (ER ampersand WM) Program, many of the environments are considered hazardous, both, in the structure and composition of the environment Use of a sensing system that provides information to the manipulator control unit regarding obstacles in close proximity will provide protection against collisions. In this paper, a hierarchical design and implementation of a whole-arm obstacle avoidance system is presented. The system is based on capacitive sensors configured as bracelets for proximity sensing. Each bracelet contains a number of sensor nodes and a processor for sensor node control and readout, and communications with a higher level host, common to all bracelets. The host controls the entire sensing network and communicates proximity information to the manipulator controller. The overall architecture of this system is discussed with detail on the individual system modules. Details of an application specific integrated circuit (ASIC) designed to implement the sensor node electronics are presented. Justifications for the general measurement methods and associated implementation are discussed. Additionally, the current state of development including measured dam is presented

  7. Position Control Method For Pick And Place Robot Arm For Object Sorting System

    Directory of Open Access Journals (Sweden)

    Khin Moe Myint

    2015-08-01

    Full Text Available The more increase the number of industries in developing countries the more require labourers or workers in that. To reduce the cost of labour force and to increase the manufacturing capacity of industries the advanced robot arms are more needed. The aim of this journal is to eliminate the manual control for object sorting system.Robot arm design in this research uses two joints three links and servo motors to drive. Microcontroller is used to generate required PWM signal for servo motors. In this research the position control of robot arm was designed by using kinematic control methods. There are two types of kinematic control methods which are forward and reverse kinematic methods. In forward kinematic method the input parameters are the joint angles and link length of robot arm and then the output is the position at XYZ coordinate of tool or gripper. In inverse kinematic the input parameters are position at XYZ coordinate of gripper and the link length of robot arm and then the output parameters are the joint angles. So kinematic methods can explain the analytical description of the geometry motion of the manipulator with reference to a robot coordinate system fixed to a frame without consideration of the forces or the moments causing the movements. For sorting system Metal detector is used to detect the metal or non-metal. This position control of pick and place robot arm is fully tested and the result is obtained more precisely.

  8. Precision Munition Electro-Sciences Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This facility allows the characterization of the electro-magnetic environment produced by a precision weapon in free flight. It can measure the radiofrequency (RF)...

  9. Innovative technology summary report: Light duty utility arm

    International Nuclear Information System (INIS)

    1998-01-01

    The Light-Duty Utility Arm (LDUA) System is a mobile, multi-axis positioning system capable of deploying tools and sensors (end effecters) inside radioactive waste tanks for tank wall inspection, waste characterization, and waste retrieval. The LDUA robotic manipulator enters a tank through existing openings (risers) in the tank dome of the underground tanks. Using various end effecters, the LDUA System is a versatile system for high-level waste tank remediation. The LDUA System provides a means to deploy tools, while increasing the technology resources available to the U.S. Department of Energy (DOE). Ongoing end effecter development will provide additional capabilities to remediate the waste tanks

  10. The Development of Control System Design for 5 DOF Nuclear Malaysia Robot Arm v2

    International Nuclear Information System (INIS)

    Mohd Zaid Hassan; Anwar Abdul Rahman; Rosli Darmawan; Mohd Arif Hamzah

    2011-01-01

    This paper describes a general design and implementation approach used for programming and controlling robotic systems such as remotely operated robotic manipulator systems. A hierarchical approach to control system design is adopted. The hierarchical design is translated into a component-based software design. A low-cost robotic arm and controller system is presented. The controller is a modular model of the robotic arm with the same degrees of freedom whose joints are equipped with sensors. The system takes advantage of the low cost and wide availability of control components and uses a low-cost, easy-to-program microprocessor. Furthermore, it presents the design and the construction of electronic systems for the control of an articulated robot developed for research and development related with instrumentation and control. The system is simple but it is designed the motor to move the robot arm to proper angular position according to the input controller. Limitations of the micro controller are discussed, and suggestions for further development of the robot arm and control are made. (author)

  11. Factors impacting the electro conductivity variations of clayey soils

    International Nuclear Information System (INIS)

    Ouhadi, V. R.; Goodarzi, A. R.

    2007-01-01

    The variation of pore fluid properties in soil has a major effect on soil behaviour. This effect is a function of pore fluid properties and soil mineralogy. Such variation usually happens in the reservoirs of dams or in some geotechnical projects. The electro conductivity measurement is a simple method to monitor any variation in the pore fluid of soils. electro conductivity is the ability of a material to transmit (conduct) an electrical current. This paper focuses attention on the effect of soil-pore fluid interaction on the electro conductivity of clayey soils. A set of physico-chemical experiments are performed and the role of different factors including soil pH, soil mineralogy, soil: water ratio, cation and anion effects are investigated. The results of this study indicate that for soil that has a relatively low CEC, the anion type is an important factor, while the cation type does not noticeably affect the electro conductivity of the soil-solution. However, for such soil, an electrolyte property, i.e. its solubility, is much more effective than the CEC of the soil. In addition, it was observed that in the presence of neutral salts such as pore fluid, the pH of the soil-solution decreases causing an increase in the electro conductivity of the soil sample

  12. Autonomous path planning solution for industrial robot manipulator using backpropagation algorithm

    Directory of Open Access Journals (Sweden)

    PeiJiang Yuan

    2015-12-01

    Full Text Available Here, we propose an autonomous path planning solution using backpropagation algorithm. The mechanism of movement used by humans in controlling their arms is analyzed and then applied to control a robot manipulator. Autonomous path planning solution is a numerical method. The model of industrial robot manipulator used in this article is a KUKA KR 210 R2700 EXTRA robot. In order to show the performance of the autonomous path planning solution, an experiment validation of path tracking is provided. Experiment validation consists of implementation of the autonomous path planning solution and the control of physical robot. The process of converging to target solution is provided. The mean absolute error of position for tool center point is also analyzed. Comparison between autonomous path planning solution and the numerical methods based on Newton–Raphson algorithm is provided to demonstrate the efficiency and accuracy of the autonomous path planning solution.

  13. Proprioceptive Interaction between the Two Arms in a Single-Arm Pointing Task.

    Directory of Open Access Journals (Sweden)

    Kazuyoshi Kigawa

    Full Text Available Proprioceptive signals coming from both arms are used to determine the perceived position of one arm in a two-arm matching task. Here, we examined whether the perceived position of one arm is affected by proprioceptive signals from the other arm in a one-arm pointing task in which participants specified the perceived position of an unseen reference arm with an indicator paddle. Both arms were hidden from the participant's view throughout the study. In Experiment 1, with both arms placed in front of the body, the participants received 70-80 Hz vibration to the elbow flexors of the reference arm (= right arm to induce the illusion of elbow extension. This extension illusion was compared with that when the left arm elbow flexors were vibrated or not. The degree of the vibration-induced extension illusion of the right arm was reduced in the presence of left arm vibration. In Experiment 2, we found that this kinesthetic interaction between the two arms did not occur when the left arm was vibrated in an abducted position. In Experiment 3, the vibration-induced extension illusion of one arm was fully developed when this arm was placed at an abducted position, indicating that the brain receives increased proprioceptive input from a vibrated arm even if the arm was abducted. Our results suggest that proprioceptive interaction between the two arms occurs in a one-arm pointing task when the two arms are aligned with one another. The position sense of one arm measured using a pointer appears to include the influences of incoming information from the other arm when both arms were placed in front of the body and parallel to one another.

  14. Handbook of hydraulic fluid technology

    CERN Document Server

    Totten, George E

    2011-01-01

    ""The Handbook of Hydraulic Fluid Technology"" serves as the foremost resource for designing hydraulic systems and for selecting hydraulic fluids used in engineering applications. Featuring new illustrations, data tables, as well as practical examples, this second edition is updated with essential information on the latest hydraulic fluids and testing methods. The detailed text facilitates unparalleled understanding of the total hydraulic system, including important hardware, fluid properties, and hydraulic lubricants. Written by worldwide experts, the book also offers a rigorous overview of h

  15. Future electro-optical sensors and processing in urban operations

    NARCIS (Netherlands)

    Grönwall, C.; Schwering, P.B.; Rantakokko, J.; Benoist, K.W.; Kemp, R.A.W.; Steinvall, O.; Letalick, D.; Björkert, S.

    2013-01-01

    In the electro-optical sensors and processing in urban operations (ESUO) study we pave the way for the European Defence Agency (EDA) group of Electro-Optics experts (IAP03) for a common understanding of the optimal distribution of processing functions between the different platforms. Combinations of

  16. Electro-spun PLA-PEG-yarns for tissue engineering applications

    NARCIS (Netherlands)

    Kruse, Magnus; Greuel, Marc; Kreimendahl, Franziska; Schneiders, Thomas; Bauer, Benedict; Gries, Thomas; Jockenhoevel, Stefan

    2018-01-01

    Electro-spinning is widely used in tissue-engineered applications mostly in form of non-woven structures. The development of e-spun yarn opens the door for textile fabrics which combine the micro to nanoscale dimension of electro-spun filaments with three-dimensional (3D) drapable textile fabrics.

  17. Electro-membrane microcurrent therapy reduces signs and symptoms of muscle damage.

    Science.gov (United States)

    Lambert, Michael I; Marcus, Paul; Burgess, Theresa; Noakes, Timothy D

    2002-04-01

    Delayed onset muscle soreness (DOMS) occurs after unaccustomed physical activity or competitive sport, resulting in stiff, painful muscles with impaired function. Acustat electro-membrane microcurrent therapy has been used to treat postoperative pain and soft tissue injury; however, its efficacy in reducing symptoms of muscle damage is not known. Thirty healthy men were recruited for a double-blind, placebo-controlled trial. The muscles of their nondominant arms were damaged using an eccentric-exercise protocol. Subjects were then randomly assigned to treatment with either Acustat or a matching placebo membrane for 96 h and monitored for a total of 168 h. Subjects in both groups experienced severe pain and swelling of the elbow flexors after the eccentric exercise. After 24 h, the elbow joint angle of the placebo group had increased significantly more than those in the Acustat group (13.7 +/- 8.9 degrees vs 7.5 +/- 5.5 degrees; placebo vs Acustat, P microcurrent therapy reduces the severity of the symptoms. The mechanisms of action are unknown but are likely related to maintenance of intracellular Ca2+ homeostasis after muscle damaging exercise.

  18. An Electro-thermal MEMS Gripper with Large Tip Opening and Holding Force: Design and Characterization

    Directory of Open Access Journals (Sweden)

    Jay J. KHAZAAI

    2011-12-01

    Full Text Available This paper presents the design, fabrication, and characterization of a novel MEMS gripper that is driven electro-thermally by a new V-shape actuator (VSA and a set of modified Guckel U-shape actuators (mUSA. The modification of the angle between the hot and cold arms in the mUSA facilitates unidirectional in-plane displacement causing the opening of the gripper. This configuration distinguishes the MEMS gripper from others in its ability to generate larger tip displacement and greater holding force. The metallic structures allow for a low operating voltage and low overall power consumption. A tip opening of 173.4 μm has been measured at the operating voltage of 1 V with consuming power of 0.85 W. MetalMUMPs is employed to fabricate the device, in which electroplated nickel is used as the structural material.

  19. Manipulator Performance Evaluation Using Fitts' Taping Task

    Energy Technology Data Exchange (ETDEWEB)

    Draper, J.V.; Jared, B.C.; Noakes, M.W.

    1999-04-25

    Metaphorically, a teleoperator with master controllers projects the user's arms and hands into a re- mote area, Therefore, human users interact with teleoperators at a more fundamental level than they do with most human-machine systems. Instead of inputting decisions about how the system should func- tion, teleoperator users input the movements they might make if they were truly in the remote area and the remote machine must recreate their trajectories and impedance. This intense human-machine inter- action requires displays and controls more carefully attuned to human motor capabilities than is neces- sary with most systems. It is important for teleoperated manipulators to be able to recreate human trajectories and impedance in real time. One method for assessing manipulator performance is to observe how well a system be- haves while a human user completes human dexterity tasks with it. Fitts' tapping task has been, used many times in the past for this purpose. This report describes such a performance assessment. The International Submarine Engineering (ISE) Autonomous/Teleoperated Operations Manipulator (ATOM) servomanipulator system was evalu- ated using a generic positioning accuracy task. The task is a simple one but has the merits of (1) pro- ducing a performance function estimate rather than a point estimate and (2) being widely used in the past for human and servomanipulator dexterity tests. Results of testing using this task may, therefore, allow comparison with other manipulators, and is generically representative of a broad class of tasks. Results of the testing indicate that the ATOM manipulator is capable of performing the task. Force reflection had a negative impact on task efficiency in these data. This was most likely caused by the high resistance to movement the master controller exhibited with the force reflection engaged. Measurements of exerted forces were not made, so it is not possible to say whether the force reflection helped

  20. Preliminary safety equipment list for Tank 241-C-106 Manipulator Retrieval System, Project W-340

    International Nuclear Information System (INIS)

    Guthrie, R.L.

    1994-01-01

    This document identifies the anticipated safety classification of the estimated major subsystems, based on the projected major functions, that will be used as guidance for the development of the conceptual design of the Manipulator Retrieval System for Tank 241-C-106. This document is intended to be updated as the design of the Manipulator Retrieval System evolves through the conceptual and definitive design phases. The Manipulator Retrieval System is to be capable of removing the hardened sludge heel at the bottom of single shell Tank 241-C-106 and to perform an overall clean out of the tank that leaves a maximum of 360 ft 3 (TPA milestone M-45-00). The thickness of the heel prior to initiation of waste retrieval with the Manipulator Retrieval System is estimated to be 1- to 2-ft. The Manipulator Retrieval System is currently in the pre-conceptual phase with no definitive systems or subsystems. The anticipated retrieval functions for the Manipulator Retrieval System is based on Table 6-2 of WHC-SD-W340-ES-001, Rev. 1. Projected equipment to accomplish these functions were based on the following systems and equipment: Rotary Mode Core Sampling Equipment (WHC-SD-WM-SEL-032); Light Duty Utility Arm System Equipment (WHC-SD-WM-SEL-034); Single Shell Tanks Equipment (WHC-SD-WM-SEL-020)

  1. Visual Servoing for Object Manipulation: A Case Study in Slaughterhouse

    DEFF Research Database (Denmark)

    Wu, Haiyan; Andersen, Thomas Timm; Andersen, Nils Axel

    2016-01-01

    Automation for slaughterhouse challenges the design of the control system due to the variety of the objects. Realtime sensing provides instantaneous information about each piece of work and thus, is useful for robotic system developed for slaughterhouse. In this work, a pick and place task which....... An online and offline combined path planning algorithm is proposed to generate the desired path for the robot control. An industrial robot arm is applied to execute the path. The system is implemented for a lab-scale experiment, and the results show a high success rate of object manipulation in the pick...

  2. High-speed 2 × 2 silicon-based electro-optic switch with nanosecond switch time

    International Nuclear Information System (INIS)

    Xue-Jun, Xu; Shao-Wu, Chen; Hai-Hua, Xu; Yang, Sun; Yu-De, Yu; Jin-Zhong, Yu; Qi-Ming, Wang

    2009-01-01

    A 2 × 2 electro-optic switch is experimentally demonstrated using the optical structure of a Mach–Zehnder interferometer (MZI) based on a submicron rib waveguide and the electrical structure of a PIN diode on silicon-on-insulator (SOI). The switch behaviour is achieved through the plasma dispersion effect of silicon. The device has a modulation arm of 1 mm in length and cross-section of 400 nm×340 nm. The measurement results show that the switch has a V π L π figure of merit of 0.145 V·cm and the extinction ratios of two output ports and cross talk are 40 dB, 28 dB and −28 dB, respectively. A 3 dB modulation bandwidth of 90 MHz and a switch time of 6.8 ns for the rise edge and 2.7 ns for the fall edge are also demonstrated

  3. EVALUATION OF STATE-OF-THE-ART MANIPULATORS AND REQUIREMENTS FOR DOE ROBOTICS APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    BLACK, DEREK; GRUPINSKI, STEPHEN

    1998-10-08

    This report provides an overview of applications within the DOE complex which could benefit from the use of modular robotics technology during remediation operations. Each application area contains one or more specific tasks which are presently conducted by humans under hazardous conditions or which are deemed highly impractical, or are altogether impossible without automation. Five major areas were investigated for specific needs with respect to automation. Information was collected on Mixed Waste Operations, Contaminant Automated Analysis, Tanks, Decontamination and Dismantlement and Automated Plutonium Processing. During this investigation, information was gathered from available literature, telephone interviews with informed personnel and on-site visits. This data serves to provide design requirements and guidelines for the design of a family of modular actuators, which will be used to construct manipulators suited to each task. In addition, a survey of existing modular manipulator designs is presented. This survey addresses modular manipulators developed inside government labs and in universities for such applications as space exploration or controls research. It also addresses efforts at commercially viable industrial manipulators which have been built. This survey of robotic systems provides the reader with a glimpse into what technology currently exists in the way of modular manipulator automation and, to a degree, where this technology may be applicable or, more often, where these systems are unsuited to EM applications. From the information gathered during this study, it is possible to sufficiently define the requirements of one manipulator system which can be used to conduct automated transfer operations within Plutonium gloveboxes. This manipulator will be constructed from ARM Automation actuator modules and will provide this application with a viable option for automation within these gloveboxes. The design issues surrounding this manipulator and its

  4. Nano-funnels as electro-osmotic ``tweezers and pistons''

    Science.gov (United States)

    Wang, Yanqian; Panyukov, Sergey; Zhou, Jinsheng; Menard, Laurent D.; Ramsey, J. Michael; Rubinstien, Michael

    2014-03-01

    An electric field is used to force a DNA molecule into a nano-channel by compensating the free energy penalty that results from the reduced conformational entropy of the confined macromolecule. Narrow nano-channels require high critical electric fields to achieve DNA translocation, leading to short dwell times of DNA in these channels. We demonstrate that nano-funnels integrated with nano-channels reduce the free energy barrier and lower the critical electric field required for DNA translocation. A focused electric field within the funnel increases the electric force on the DNA, compresses the molecule, and increases the osmotic pressure at the nano-channel entrance. This ``electro-osmotic piston'' forces the molecule into the nano-channel at lower electric fields than those observed without the funnel. Appropirately designed nano-funnels can also function as tweezers that allow manipulation of the position of the DNA molecule. The predictions of our theory describing double-stranded DNA behavior in nano-funnel - nano-channel devices are consistent with experimental results. Thanks for the financial support from NSF (DMR-1309892, DMR-1121107, DMR-1122483), NIH (1-P50-HL107168, 1-P01-HL108808-01A1, R01HG02647), NHGRI and CF Foundation.

  5. Electro-optical frequency shifting of lasers for plasma diagnostics

    International Nuclear Information System (INIS)

    Forman, P.R.

    1977-07-01

    An electro-optical frequency shifting device is proposed as an aid for plasma physics heterodyne interferometry and heterodyne scattering experiments. The method has the advantage over other electro-optic shifters, that a pure separable frequency shifted beam can be obtained even when less than half wave voltage is applied. (orig.) [de

  6. Testing of an End-Point Control Unit Designed to Enable Precision Control of Manipulator-Coupled Spacecraft

    Science.gov (United States)

    Montgomery, Raymond C.; Ghosh, Dave; Tobbe, Patrick A.; Weathers, John M.; Manouchehri, Davoud; Lindsay, Thomas S.

    1994-01-01

    This paper presents an end-point control concept designed to enable precision telerobotic control of manipulator-coupled spacecraft. The concept employs a hardware unit (end-point control unit EPCU) that is positioned between the end-effector of the Space Shuttle Remote Manipulator System and the payload. Features of the unit are active compliance (control of the displacement between the end-effector and the payload), to allow precision control of payload motions, and inertial load relief, to prevent the transmission of loads between the end-effector and the payload. This paper presents the concept and studies the active compliance feature using a simulation and hardware. Results of the simulation show the effectiveness of the EPCU in smoothing the motion of the payload. Results are presented from initial, limited tests of a laboratory hardware unit on a robotic arm testbed at the l Space Flight Center. Tracking performance of the arm in a constant speed automated retraction and extension maneuver of a heavy payload with and without the unit active is compared for the design speed and higher speeds. Simultaneous load reduction and tracking performance are demonstrated using the EPCU.

  7. Robotic arm

    Science.gov (United States)

    Kwech, Horst

    1989-04-18

    A robotic arm positionable within a nuclear vessel by access through a small diameter opening and having a mounting tube supported within the vessel and mounting a plurality of arm sections for movement lengthwise of the mounting tube as well as for movement out of a window provided in the wall of the mounting tube. An end effector, such as a grinding head or welding element, at an operating end of the robotic arm, can be located and operated within the nuclear vessel through movement derived from six different axes of motion provided by mounting and drive connections between arm sections of the robotic arm. The movements are achieved by operation of remotely-controllable servo motors, all of which are mounted at a control end of the robotic arm to be outside the nuclear vessel.

  8. Development of Direct Kinematics and Workspace Representation for Smokie Robot Manipulator & the Barret WAM

    OpenAIRE

    Abdolmalaki, Reza Yazdanpanah

    2017-01-01

    This paper discusses modelling two 6 DOF arm robots. The first step of modelling a robot is establishing its Denavit-Hartenberg parameters. It requires assigning proper coordinates for each link and finding their exact dimensions. In this project we will develop the direct kinematics and workspace representations for two manipulators: the Smokie Robot and the Barrett WAM. After finding the D-H parameters and creating Transformation Matrices,MATLAB programming is used to represent their worksp...

  9. Evaluation of head-collision safety of a 7-DOF manipulator according to posture variation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Hong, E-mail: rome582@khu.ac.kr; Park, In Jun, E-mail: demianjun@gmail.com; Choi, Jin-Hwan, E-mail: jhchoi@khu.ac.kr; Rhim, Sungsoo, E-mail: ssrhim@khu.ac.kr [Kyung Hee University, Department of Mechanical Engineering (Korea, Republic of)

    2016-05-15

    As the need for the improvement of the productivity in the manufacturing process grows, industrial robots are brought out of the safety fences and used in the direct collaborative operation with human workers. Consequently, the intended and/or unintended contact between the human and the robot in the collaborative operation is no longer an extraordinary event and is a mundane possibility. The level of the risk of the collision depends on various quantities associated with the collision, for example, inertia, velocity, stiffness, and so on. MSI (manipulator safety index) which is based on HIC (head injury criteria) conventionally used in the automotive industry is one of the practically available measures to estimate the risk of the collision between the human and the manipulator. In this paper MSI is applied to evaluate the collision safety of a 7-DOF articulated human-arm-like manipulator. The risk of the collision could be reduced by choosing different postures without deviating from the given end-effector trajectory using the redundant degree of freedom in the 7-DOF manipulator. The paper shows how the redundant degree of the freedom is utilized to design safer trajectories and/or safer manipulator configurations among many available. A parametric analysis and simulation results for a given trajectory illustrate the usefulness of the concept of the trajectory design for alleviating the risk of the manipulator operation in the human–robot coexisting workspace.

  10. High performance electro-optical modulator based on photonic crystal and graphene

    Science.gov (United States)

    Malekmohammad, M.; Asadi, R.

    2017-07-01

    An electro-optical modulator is demonstrated based on Fano-resonance effect in an out-of-plane illumination of one-dimensional slab photonic crystal composed of two graphene layers. It has been shown that high sensitivity of the Fano-resonance and electro-refractive tuning of graphene layers provides a suitable condition to obtain an electro-optical modulator with low energy consumption (8 pJ) with contrast of 0.4.

  11. Electro-decontamination of cementitious materials

    International Nuclear Information System (INIS)

    Ben-Hadj-Hassine, S.

    2012-01-01

    The end of operations in nuclear facilities is followed by various decontamination and decommissioning operations. Similar to other electrochemical techniques such as re-alkalinisation and chloride extraction, an electrokinetic remediation process is being developed as a specific method for deeply contaminated concrete structures. Two cements, an ordinary Portland and a 30% slag cement, have been chosen for the conducted work.Mortars and concretes are contaminated by adding non-radioactive cesium in the batch water, cesium being a representative specie of deep encountered contaminants. The conducted experimental and numerical work have focused on three main aspects: characterizing and understanding the cesium transport mechanisms, assessing the electro-remediation process at lab-scale and evaluating the real scale constraints. Using existing knowledge of chloride transport mechanisms, experiments have been conducted to characterize the cesium interactions with cementitious phase and ionic transport in saturated materials. A numerical model have then been developed to describe the cesium transport, taking into account the ionic activity coefficients and interactions with solid phases. Indeed, lab-scale experiments have demonstrated that electro-remediation reduced to 20-50% the initially contained cesium after a three weeks treatment. Treated samples analysis confirmed that deeply diffused cesium is migrating to the surface. Moreover, conducted experiments showed the consistency between the different materials properties, applied currents and decontamination efficiency. A comparative analysis of experiments carried on samples with different shapes, formulations and contamination modes helped assessing and optimizing the process efficiency for various continuous and variable applied currents. Finally, electro-remediation experiments have also been carried on 1m 2 concrete slabs. Liquid catholyte and anolyte solutions are replaced by alumina gels and cellulose pastes

  12. Electro-optical hybrid slip ring

    Science.gov (United States)

    Hong, En

    2005-11-01

    The slip ring is a rotary electrical interface, collector, swivel or rotary joint. It is a physical system that can perform continuous data transfer and data exchange between a stationary and a rotating structure. A slip ring is generally used to transfer data or power from an unrestrained, continuously rotating electro-mechanical system in real-time, thereby simplifying operations and eliminating damage-prone wires dangling from moving joints. Slip rings are widely used for testing, evaluating, developing and improving various technical equipment and facilities with rotating parts. They are widely used in industry, especially in manufacturing industries employing turbo machinery, as in aviation, shipbuilding, aerospace, defense, and in precise facilities having rotating parts such as medical Computerized Tomography (CT) and MRI scanners and so forth. Therefore, any improvement in slip ring technology can impact large markets. Research and development in this field will have broad prospects long into the future. The goal in developing the current slip ring technology is to improve and increase the reliability, stability, anti-interference, and high data fidelity between rotating and stationary structures. Up to now, there have been numerous approaches used for signal and data transfer utilizing a slip ring such as metal contacts, wires, radio transmission, and even liquid media. However, all suffer from drawbacks such as data transfer speed limitations, reliability, stability, electro-magnetic interference and durability. The purpose of the current research is to break through these basic limitations using an optical solution, thereby improving performance in current slip ring applications. This dissertation introduces a novel Electro-Optical Hybrid Slip Ring technology, which makes "through the air" digital-optical communication between stationary and rotating systems a reality with high data transfer speed, better reliability and low interference susceptibility

  13. Surface effects on anti-plane shear waves propagating in magneto-electro-elastic nanoplates

    International Nuclear Information System (INIS)

    Wu, Bin; Zhang, Chunli; Chen, Weiqiu; Zhang, Chuanzeng

    2015-01-01

    Material surfaces may have a remarkable effect on the mechanical behavior of magneto-electro-elastic (or multiferroic) structures at nanoscale. In this paper, a surface magneto-electro-elasticity theory (or effective boundary condition formulation), which governs the motion of the material surface of magneto-electro-elastic nanoplates, is established by employing the state-space formalism. The properties of anti-plane shear (SH) waves propagating in a transversely isotropic magneto-electro-elastic plate with nanothickness are investigated by taking surface effects into account. The size-dependent dispersion relations of both antisymmetric and symmetric SH waves are presented. The thickness-shear frequencies and the asymptotic characteristics of the dispersion relations considering surface effects are determined analytically as well. Numerical results show that surface effects play a very pronounced role in elastic wave propagation in magneto-electro-elastic nanoplates, and the dispersion properties depend strongly on the chosen surface material parameters of magneto-electro-elastic nanoplates. As a consequence, it is possible to modulate the waves in magneto-electro-elastic nanoplates through surface engineering. (paper)

  14. The transverse shear deformation behaviour of magneto-electro-elastic shell

    International Nuclear Information System (INIS)

    Albarody, Thar M. Badri; Al-Kayiem, Hussain H.; Faris, Waleed

    2016-01-01

    Compared to the large number of possible magneto-electro-elastic shell theories, very few exact solutions determining the in-plane stresses, electric displacements and magnetic inductions are possible. While, solving the magneto-electro-elastic shell equations in terms of thermo-magneto-electro-elastic generalized field functions on arbitrary domains and for general conditions exactly are not always possible. In the present work, a linear version of magneto-electro-elastic shell with simply supported boundary conditions, solved exactly, provided that the lamination scheme is cross-ply or anti-symmetric angle-ply laminates. The exact solution that introduced herein can measure the in-plane stresses, electric displacements and magnetic inductions. It also allow for an accurate and usually elegant and conclusive investigation of the various sensations in a shell structure. However, it is important for micro-electro-mechanical shell applications to have an approach available that gives the transverse shear deformation Behaviour for cases that cannot examine experimentally. An investigated examples were accompanied and noteworthy conclusions were drawn which highlight the issues of the implementation of the exact solution, implication of the effects of the material properties, lay-ups of the constituent layers, and shell parameters on the static Behaviour

  15. The transverse shear deformation behaviour of magneto-electro-elastic shell

    Energy Technology Data Exchange (ETDEWEB)

    Albarody, Thar M. Badri; Al-Kayiem, Hussain H. [UniversitiTeknologi PETRONAS, Perak (Malaysia); Faris, Waleed [International Islamic University Malaysia, Perak (Malaysia)

    2016-01-15

    Compared to the large number of possible magneto-electro-elastic shell theories, very few exact solutions determining the in-plane stresses, electric displacements and magnetic inductions are possible. While, solving the magneto-electro-elastic shell equations in terms of thermo-magneto-electro-elastic generalized field functions on arbitrary domains and for general conditions exactly are not always possible. In the present work, a linear version of magneto-electro-elastic shell with simply supported boundary conditions, solved exactly, provided that the lamination scheme is cross-ply or anti-symmetric angle-ply laminates. The exact solution that introduced herein can measure the in-plane stresses, electric displacements and magnetic inductions. It also allow for an accurate and usually elegant and conclusive investigation of the various sensations in a shell structure. However, it is important for micro-electro-mechanical shell applications to have an approach available that gives the transverse shear deformation Behaviour for cases that cannot examine experimentally. An investigated examples were accompanied and noteworthy conclusions were drawn which highlight the issues of the implementation of the exact solution, implication of the effects of the material properties, lay-ups of the constituent layers, and shell parameters on the static Behaviour.

  16. Geometric technique for the kinematic modeling of a 5 DOF redundant manipulator

    CSIR Research Space (South Africa)

    Makondo, N

    2012-11-01

    Full Text Available ,? Dipartimento di Elettronica, Informatica e Sistemistica (DEIS), Universit a di Bologna [Online]; Available at: http://www- lar.deis.unibo.it/people/cmelchiorri/Files Robotica/FIR 04 Kinem.pdf[31 October 2012] [18] Manocha, D.; Canny, J.F.; , ?Efficient... to the inverse kinematics of the Pioneer 2 robotic arm ?, Robotica, 2005, vol.23, pp.123, DOI: 10.1017/S0263574704000529 [20] De Xu, Carlos A. Acosta Calderon, John Q. Gan etc .An Analysis of the Inverse Kinematics for a 5-DOF Manipulator, International...

  17. Electro-optical rendezvous and docking sensors

    Science.gov (United States)

    Tubbs, David J.; Kesler, Lynn O.; Sirko, Robert J.

    1991-01-01

    Electro-optical sensors provide unique and critical functionality for space missions requiring rendezvous, docking, and berthing. McDonnell Douglas is developing a complete rendezvous and docking system for both manned and unmanned missions. This paper examines our sensor development and the systems and missions which benefit from rendezvous and docking sensors. Simulation results quantifying system performance improvements in key areas are given, with associated sensor performance requirements. A brief review of NASA-funded development activities and the current performance of electro-optical sensors for space applications is given. We will also describe current activities at McDonnell Douglas for a fully functional demonstration to address specific NASA mission needs.

  18. The Multi-Porosity Multi-Permeability and Electrokinetic Natures of Shales and Their Effects in Hydraulic Fracturing of Unconventional Shale Reservoirs

    Science.gov (United States)

    Liu, C.; Hoang, S. K.; Tran, M. H.; Abousleiman, Y. N.

    2013-12-01

    Imaging studies of unconventional shale reservoir rocks have recently revealed the multi-porosity multi-permeability nature of these intricate formations. In particular, the porosity spectrum of shale reservoir rocks often comprises of the nano-porosity in the organic matters, the inter-particle micro-porosity, and the macroscopic porosity of the natural fracture network. Shale is also well-known for its chemically active behaviors, especially shrinking and swelling when exposed to aqueous solutions, as the results of pore fluid exchange with external environment due to the difference in electro-chemical potentials. In this work, the effects of natural fractures and electrokinetic nature of shale on the formation responses during hydraulic fracturing are examined using the dual-poro-chemo-electro-elasticity approach which is a generalization of the classical Biot's poroelastic formulation. The analyses show that the presence of natural fractures can substantially increase the leak-off rate of fracturing fluid into the formation and create a larger region of high pore pressure near the fracture face as shown in Fig.1a. Due to the additional fluid invasion, the naturally fractured shale swells up more and the fracture aperture closes faster compared to an intrinsically low permeability non-fractured shale formation as shown in Fig.1b. Since naturally fractured zones are commonly targeted as pay zones, it is important to account for the faster fracture closing rate in fractured shales in hydraulic fracturing design. Our results also show that the presence of negative fixed charges on the surface of clay minerals creates an osmotic pressure at the interface of the shale and the external fluid as shown in Fig.1c. This additional Donnan-induced pore pressure can result in significant tensile effective stresses and tensile damage in the shale as shown in Fig.1d. The induced tensile damage can exacerbate the problem of proppant embedment resulting in more fracture closure

  19. Robotic arm

    International Nuclear Information System (INIS)

    Kwech, H.

    1989-01-01

    A robotic arm positionable within a nuclear vessel by access through a small diameter opening and having a mounting tube supported within the vessel and mounting a plurality of arm sections for movement lengthwise of the mounting tube as well as for movement out of a window provided in the wall of the mounting tube is disclosed. An end effector, such as a grinding head or welding element, at an operating end of the robotic arm, can be located and operated within the nuclear vessel through movement derived from six different axes of motion provided by mounting and drive connections between arm sections of the robotic arm. The movements are achieved by operation of remotely-controllable servo motors, all of which are mounted at a control end of the robotic arm to be outside the nuclear vessel. 23 figs

  20. Control rod drive hydraulic device

    International Nuclear Information System (INIS)

    Takekawa, Toru.

    1994-01-01

    The device of the present invention can reliably prevent a possible erroneous withdrawal of control rod driving mechanism when the pressure of a coolant line is increased by isolation operation of hydraulic control units upon periodical inspection for a BWR type reactor. That is, a coolant line is connected to the downstream of a hydraulic supply device. The coolant line is connected to a hydraulic control unit. A coolant hydraulic detection device and a pressure setting device are disposed to the coolant line. A closing signal line and a returning signal line are disposed, which connect the hydraulic supply device and a flow rate control valve for the hydraulic setting device. In the device of the present invention, even if pressure of supplied coolants is elevated due to isolation of hydraulic control units, the elevation of the hydraulic pressure can be prevented. Accordingly, reliability upon periodical reactor inspection can be improved. Further, the facility is simplified and the installation to an existent facility is easy. (I.S.)

  1. Study on Characteristics of Hydraulic Servo System for Force Control of Hydraulic Robots

    International Nuclear Information System (INIS)

    Kim, Hyo-gon; Han, Changsoo; Lee, Jong-won; Park, Sangdeok

    2015-01-01

    Because a hydraulic actuator has high power and force densities, this allows the weight of the robot's limbs to be reduced. This allows for good dynamic characteristics and high energy efficiency. Thus, hydraulic actuators are used in some exoskeleton robots and quadrupedal robots that require high torque. Force control is useful for robot compliance with a user or environment. However, force control of a hydraulic robot is difficult because a hydraulic servo system is highly nonlinear from a control perspective. In this study, a nonlinear model was used to develop a simulation program for a hydraulic servo system consisting of a servo valve, transmission lines, and a cylinder. The problems and considerations with regard to the force control performance for a hydraulic servo system were investigated. A force control method using the nonlinear model was proposed, and its effect was evaluated with the simulation program

  2. Study on Characteristics of Hydraulic Servo System for Force Control of Hydraulic Robots

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyo-gon; Han, Changsoo [Hanyang University, Seoul (Korea, Republic of); Lee, Jong-won [Korea University of Science and Technology, Seoul (Korea, Republic of); Park, Sangdeok [Korea Institute of Industrial Technology, Seoul (Korea, Republic of)

    2015-02-15

    Because a hydraulic actuator has high power and force densities, this allows the weight of the robot's limbs to be reduced. This allows for good dynamic characteristics and high energy efficiency. Thus, hydraulic actuators are used in some exoskeleton robots and quadrupedal robots that require high torque. Force control is useful for robot compliance with a user or environment. However, force control of a hydraulic robot is difficult because a hydraulic servo system is highly nonlinear from a control perspective. In this study, a nonlinear model was used to develop a simulation program for a hydraulic servo system consisting of a servo valve, transmission lines, and a cylinder. The problems and considerations with regard to the force control performance for a hydraulic servo system were investigated. A force control method using the nonlinear model was proposed, and its effect was evaluated with the simulation program.

  3. Hydraulic Hybrid Vehicles

    Science.gov (United States)

    EPA and the United Parcel Service (UPS) have developed a hydraulic hybrid delivery vehicle to explore and demonstrate the environmental benefits of the hydraulic hybrid for urban pick-up and delivery fleets.

  4. New Design Concept for an Excavator Arms by Using Composite Material

    Science.gov (United States)

    Solazzi, L.; Assi, A.; Ceresoli, F.

    2018-06-01

    The purpose of the present paper is to lightweight design an excavator arms, by using a different materials and in particular composite material. Specifically, the research is based on the study of a commercial excavator, by determining its geometry and analyzing the load conditions to which it is exposed. These are determined in relation to either the load diagram of the machine or the possible utilities of the excavator, such as the rotation of the machine. The materials used and implemented in the different analytical and numerical elaborations are classic construction steel S 355 (UNI EN 10025-3), high-resistance steel S 890 (UNI EN 10025-6), aluminum Al 6063 T6 (UNI EN 573-3) and the composite material made by carbon fiber and epoxy resin. The adopted constraints for the design of new arms with different materials, non-conventional for these applications, are numerous. The new solutions must present a safety factor either with respect to the yield tensile strength or to the critical load of buckling greater than or equal to the one determined for the excavator in its original geometrical conformation. Another criterion, which has heavily conditioned the geometry of the arms, was given by the fact that the developed solutions must present a very similar value of the maximum displacement in the different load conditions analyzed. A new geometry for arms made by composite material was developed. It was an elliptical conic section, instead of the classic rectangular section, in order to use the filament winding technological process. As for the adoption of the composite material, we focused on the study and the design of this material as long as the interaction with the extremities (made of aluminum) which are interfaced either with the link between the arms or with the elements of the hydraulic plant which serves for the arms movement. From the results developed, it emerges that the solution developed by adopting composite materials is the one that permits the

  5. An analysis of electro-osmotic and magnetohydrodynamic heat pipes

    International Nuclear Information System (INIS)

    Harrison, M.A.

    1988-01-01

    Mechanically simple methods of improving heat transport in heat pipes are investigated. These methods are electro-osmotic and magnetohydrodynamic augmentation. For the electro-osmotic case, a detailed electrokinetic model is used. The electrokinetic model used includes the effects of pore surface curvature and multiple ion diffusivities. The electrokinetic model is extended to approximate the effects of elevated temperature. When the electro-osmotic model is combined with a suitable heat-pipe model, it is found that the electro-osmotic pump should be a thin membrane. Arguments are provided that support the use of a volatile electrolyte. For the magnetohydrodynamic case, a brief investigation is provided. A quasi-one-dimensional hydromagnetic duct flow model is used. This hydromagnetic model is extended to approximate flow effects unique to heat pipes. When combined with a suitable heat pipe model, it is found that there is no performance gain for the case considered. In fact, there are serious pressure-distribution problems that have not been previously recognized. Potential solutions to these pressure-distribution problems are suggested

  6. The hydraulic wheel

    International Nuclear Information System (INIS)

    Alvarez Cardona, A.

    1985-01-01

    The present article this dedicated to recover a technology that key in disuse for the appearance of other techniques. It is the hydraulic wheel with their multiple possibilities to use their energy mechanical rotational in direct form or to generate electricity directly in the fields in the place and to avoid the high cost of transport and transformation. The basic theory is described that consists in: the power of the currents of water and the hydraulic receivers. The power of the currents is determined knowing the flow and east knowing the section of the flow and its speed; they are given you formulate to know these and direct mensuration methods by means of floodgates, drains and jumps of water. The hydraulic receivers or properly this hydraulic wheels that are the machines in those that the water acts like main force and they are designed to transmit the biggest proportion possible of absolute work of the water, the hydraulic wheels of horizontal axis are the common and they are divided in: you rotate with water for under, you rotate with side water and wheels with water for above. It is analyzed each one of them, their components are described; the conditions that should complete to produce a certain power and formulate them to calculate it. There are 25 descriptive figures of the different hydraulic wheels

  7. Electro-oxidation of methanol on copper in alkaline solution

    International Nuclear Information System (INIS)

    Heli, H.; Jafarian, M.; Mahjani, M.G.; Gobal, F.

    2004-01-01

    The electro-oxidation of methanol on copper in alkaline solutions has been studied by the methods of cyclic voltammetry, quasi-steady state polarization and chronoamperometry. It has been found that in the course of an anodic potential sweep the electro-oxidation of methanol follows the formation of Cu III and is catalysed by this species through a mediated electron transfer mechanism. The reaction also continues in the early stages of the reversed cycle until it is stopped by the prohibitively negative potentials. The process is diffusion controlled and the current-time responses follow Cottrellian behavior. The rate constants, turnover frequency, anodic transfer coefficient and the apparent activation energy of the electro-oxidation reaction are reported

  8. Sensory Agreement Guides Kinetic Energy Optimization of Arm Movements during Object Manipulation.

    Directory of Open Access Journals (Sweden)

    Ali Farshchiansadegh

    2016-04-01

    Full Text Available The laws of physics establish the energetic efficiency of our movements. In some cases, like locomotion, the mechanics of the body dominate in determining the energetically optimal course of action. In other tasks, such as manipulation, energetic costs depend critically upon the variable properties of objects in the environment. Can the brain identify and follow energy-optimal motions when these motions require moving along unfamiliar trajectories? What feedback information is required for such optimal behavior to occur? To answer these questions, we asked participants to move their dominant hand between different positions while holding a virtual mechanical system with complex dynamics (a planar double pendulum. In this task, trajectories of minimum kinetic energy were along curvilinear paths. Our findings demonstrate that participants were capable of finding the energy-optimal paths, but only when provided with veridical visual and haptic information pertaining to the object, lacking which the trajectories were executed along rectilinear paths.

  9. Pick-up, transport and release of a molecular cargo using a small-molecule robotic arm

    Science.gov (United States)

    Kassem, Salma; Lee, Alan T. L.; Leigh, David A.; Markevicius, Augustinas; Solà, Jordi

    2016-02-01

    Modern-day factory assembly lines often feature robots that pick up, reposition and connect components in a programmed manner. The idea of manipulating molecular fragments in a similar way has to date only been explored using biological building blocks (specifically DNA). Here, we report on a wholly artificial small-molecule robotic arm capable of selectively transporting a molecular cargo in either direction between two spatially distinct, chemically similar, sites on a molecular platform. The arm picks up/releases a 3-mercaptopropanehydrazide cargo by formation/breakage of a disulfide bond, while dynamic hydrazone chemistry controls the cargo binding to the platform. Transport is controlled by selectively inducing conformational and configurational changes within an embedded hydrazone rotary switch that steers the robotic arm. In a three-stage operation, 79-85% of 3-mercaptopropanehydrazide molecules are transported in either (chosen) direction between the two platform sites, without the cargo at any time fully dissociating from the machine nor exchanging with other molecules in the bulk.

  10. Quantum model for electro-optical amplitude modulation.

    Science.gov (United States)

    Capmany, José; Fernández-Pousa, Carlos R

    2010-11-22

    We present a quantum model for electro-optic amplitude modulation, which is built upon quantum models of the main photonic components that constitute the modulator, that is, the guided-wave beamsplitter and the electro-optic phase modulator and accounts for all the different available modulator structures. General models are developed both for single and dual drive configurations and specific results are obtained for the most common configurations currently employed. Finally, the operation with two-photon input for the control of phase-modulated photons and the important topic of multicarrier modulation are also addressed.

  11. Electro-Conductive Membranes for Permeation Enhancement and Fouling Mitigation: A Short Review

    Directory of Open Access Journals (Sweden)

    Patrizia Formoso

    2017-07-01

    Full Text Available The research on electro-conductive membranes has expanded in recent years. These membranes have strong prospective as key components in next generation water treatment plants because they are engineered in order to enhance their performance in terms of separation, flux, fouling potential, and permselectivity. The present review summarizes recent developments in the preparation of electro-conductive membranes and the mechanisms of their response to external electric voltages in order to obtain an improvement in permeation and mitigation in the fouling growth. In particular, this paper deals with the properties of electro-conductive polymers and the preparation of electro-conductive polymer membranes with a focus on responsive membranes based on polyaniline, polypyrrole and carbon nanotubes. Then, some examples of electro-conductive membranes for permeation enhancement and fouling mitigation by electrostatic repulsion, hydrogen peroxide generation and electrochemical oxidation will be presented.

  12. Electro-Conductive Membranes for Permeation Enhancement and Fouling Mitigation: A Short Review.

    Science.gov (United States)

    Formoso, Patrizia; Pantuso, Elvira; De Filpo, Giovanni; Nicoletta, Fiore Pasquale

    2017-07-28

    The research on electro-conductive membranes has expanded in recent years. These membranes have strong prospective as key components in next generation water treatment plants because they are engineered in order to enhance their performance in terms of separation, flux, fouling potential, and permselectivity. The present review summarizes recent developments in the preparation of electro-conductive membranes and the mechanisms of their response to external electric voltages in order to obtain an improvement in permeation and mitigation in the fouling growth. In particular, this paper deals with the properties of electro-conductive polymers and the preparation of electro-conductive polymer membranes with a focus on responsive membranes based on polyaniline, polypyrrole and carbon nanotubes. Then, some examples of electro-conductive membranes for permeation enhancement and fouling mitigation by electrostatic repulsion, hydrogen peroxide generation and electrochemical oxidation will be presented.

  13. Intelligent Materials Used in Hydraulic, Fuel, and Rudder Control Systems of Aircrafts

    Directory of Open Access Journals (Sweden)

    D. B. Chernov

    2017-01-01

    Full Text Available The device is really intelligent, only if it is capable to respond to changing external conditions. The devices, which "feel" the external environment and can change their characteristics, have many advantages compared to the conventional devices: they are more efficient, wear out more slowly, and have lower operating costs.The scope of smart products is truly infinite. Alloys with memory effect also apply to intellectual content. Natural piezoelectric crystals such as silicon dioxide (intellectual material have been known for over a hundred years. They have greater stiffness and can be used at high operating frequencies. Due to the direct piezoelectric effect, they have been successfully used as a strain gage. Later came artificial ceramic piezoelectric materials; they are used as mechanical transducers. Thus, an inverse piezoelectric effect is usually used. It consists in the change of dimensions when an electric field is applied. Control of intellectual structure can be provided by heat fluxes, electromagnetic, hydraulic or piezoelectric forces and through application of electro-rheological, and magneto-rheological fluids. The article examines the intellectual materials and technologies that are already in place or will find its application in aviation hydraulic and fuel systems and control systems of rudders (CSR of aircrafts in the near future.The paper considers in detail the shape memory effect alloys (SMEA as "intelligent" materials. Actuators made from SMEA have a number of advantages: high working power; large recoverable deformation; different types of strain (tensile, compressive, bending and torsional; most specific value of the work per unit mass. All the SMEA advantages may be well used for the so-called thermo-mechanical connections (TMС of pipelines where SMEA drawbacks in this application, practically, do not affect the quality of TMC. In aircraft engineering the TMC were first used in hydraulic systems of the aircraft TU204

  14. Modeling and experiments on the drive characteristics of high-strength water hydraulic artificial muscles

    Science.gov (United States)

    Zhang, Zengmeng; Hou, Jiaoyi; Ning, Dayong; Gong, Xiaofeng; Gong, Yongjun

    2017-05-01

    Fluidic artificial muscles are popular in robotics and function as biomimetic actuators. Their pneumatic version has been widely investigated. A novel water hydraulic artificial muscle (WHAM) with high strength is developed in this study. WHAMs can be applied to underwater manipulators widely used in ocean development because of their environment-friendly characteristics, high force-to-weight ratio, and good bio-imitability. Therefore, the strength of WHAMs has been improved to fit the requirements of underwater environments and the work pressure of water hydraulic components. However, understanding the mechanical behaviors of WHAMs is necessary because WHAMs use work media and pressure control that are different from those used by pneumatic artificial muscles. This paper presents the static and dynamic characteristics of the WHAM system, including the water hydraulic pressure control circuit. A test system is designed and built to analyze the drive characteristics of the developed WHAM. The theoretical relationships among the amount of contraction, pressure, and output drawing force of the WHAM are tested and verified. A linearized transfer function is proposed, and the dynamic characteristics of the WHAM are investigated through simulation and inertia load experiments. Simulation results agree with the experimental results and show that the proposed model can be applied to the control of WHAM actuators.

  15. Missile Electro-Optical Countermeasures Simulation Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — This laboratory comprises several hardware-in-the-loop missile flight simulations designed specifically to evaluate the effectiveness of electro-optical air defense...

  16. Multi-Sensor Localization and Navigation for Remote Manipulation in Smoky Areas

    Directory of Open Access Journals (Sweden)

    Jose Vicente Marti

    2013-04-01

    Full Text Available When localizing mobile sensors and actuators in indoor environments laser meters, ultrasonic meters or even image processing techniques are usually used. On the other hand, in smoky conditions, due to a fire or building collapse, once the smoke or dust density grows, optical methods are not efficient anymore. In these scenarios other type of sensors must be used, such as sonar, radar or radiofrequency signals. Indoor localization in low-visibility conditions due to smoke is one of the EU GUARDIANS [1] project goals. The developed method aims to position a robot in front of doors, fire extinguishers and other points of interest with enough accuracy to allow a human operator to manipulate the robot's arm in order to actuate over the element. In coarse-grain localization, a fingerprinting technique based on ZigBee and WiFi signals is used, allowing the robot to navigate inside the building in order to get near the point of interest that requires manipulation. In fine-grained localization a remotely controlled programmable high intensity LED panel is used, which acts as a reference to the system in smoky conditions. Then, smoke detection and visual fine-grained localization are used to position the robot with precisely in the manipulation point (e.g., doors, valves, etc..

  17. Characteristic Length Scales in Fracture Networks: Hydraulic Connectivity through Periodic Hydraulic Tests

    Science.gov (United States)

    Becker, M.; Bour, O.; Le Borgne, T.; Longuevergne, L.; Lavenant, N.; Cole, M. C.; Guiheneuf, N.

    2017-12-01

    Determining hydraulic and transport connectivity in fractured bedrock has long been an important objective in contaminant hydrogeology, petroleum engineering, and geothermal operations. A persistent obstacle to making this determination is that the characteristic length scale is nearly impossible to determine in sparsely fractured networks. Both flow and transport occur through an unknown structure of interconnected fracture and/or fracture zones making the actual length that water or solutes travel undetermined. This poses difficulties for flow and transport models. For, example, hydraulic equations require a separation distance between pumping and observation well to determine hydraulic parameters. When wells pairs are close, the structure of the network can influence the interpretation of well separation and the flow dimension of the tested system. This issue is explored using hydraulic tests conducted in a shallow fractured crystalline rock. Periodic (oscillatory) slug tests were performed at the Ploemeur fractured rock test site located in Brittany, France. Hydraulic connectivity was examined between three zones in one well and four zones in another, located 6 m apart in map view. The wells are sufficiently close, however, that the tangential distance between the tested zones ranges between 6 and 30 m. Using standard periodic formulations of radial flow, estimates of storativity scale inversely with the square of the separation distance and hydraulic diffusivity directly with the square of the separation distance. Uncertainty in the connection paths between the two wells leads to an order of magnitude uncertainty in estimates of storativity and hydraulic diffusivity, although estimates of transmissivity are unaffected. The assumed flow dimension results in alternative estimates of hydraulic parameters. In general, one is faced with the prospect of assuming the hydraulic parameter and inverting the separation distance, or vice versa. Similar uncertainties exist

  18. The development of robotic system for the nuclear power plants - A study on the manipulation of teleoperation system using redundant robot

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chung Oh; Cho, Hyung Seok; Jang, Pyung Hoon; Park, Ki Chul; Hyun, Jang Hwan; Kim, Joo Gon; Park, Young Joon; Hwang, Woong Tae; Jeon, Yong Soo; Lee, Joo Yeon; Ahn, Kyung Mo [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1996-07-01

    In this project the following 4 sub- projects have been studied for use in nuclear power plants. 1) Development of precision control method for the hydraulic and pneumatic actuators: The fuzzy gain tuner for the pneumatic servo position control system with the state feedback controller was designed= by using the professional knowledge. Through the experimental study, this control method was verified to obtain the optimal fain automatically. 2) Development of an universal master arm and force reflecting teleoperation system: An autonomous telerobot system with a vision based force reflection capability was developed. To effectly implement visual force feedback, 3 different control methods were also developed. 3) A study on the analysis and control of the redundant robot manipulator: An optimal joint-path of 8-DOF redundant KAEROT for the nozzle dam task was generated and its effectiveness and safety was verified by using graphic/animation tool. The proposed dynamic control algorithm for the redundant robot was applied to the experiment of planar 3- DOF redundant robot, showing good performance. 4) A study on the robot/user interface design: A set of final design and its console table was developed, which has metaphorical identity and user-friendly interface and a study mock-up was also developed to identify the possibility in a clear form. 33 refs., 3 tabs., 11 figs. (author)

  19. A Velocity-Level Bi-Criteria Optimization Scheme for Coordinated Path Tracking of Dual Robot Manipulators Using Recurrent Neural Network.

    Science.gov (United States)

    Xiao, Lin; Zhang, Yongsheng; Liao, Bolin; Zhang, Zhijun; Ding, Lei; Jin, Long

    2017-01-01

    A dual-robot system is a robotic device composed of two robot arms. To eliminate the joint-angle drift and prevent the occurrence of high joint velocity, a velocity-level bi-criteria optimization scheme, which includes two criteria (i.e., the minimum velocity norm and the repetitive motion), is proposed and investigated for coordinated path tracking of dual robot manipulators. Specifically, to realize the coordinated path tracking of dual robot manipulators, two subschemes are first presented for the left and right robot manipulators. After that, such two subschemes are reformulated as two general quadratic programs (QPs), which can be formulated as one unified QP. A recurrent neural network (RNN) is thus presented to solve effectively the unified QP problem. At last, computer simulation results based on a dual three-link planar manipulator further validate the feasibility and the efficacy of the velocity-level optimization scheme for coordinated path tracking using the recurrent neural network.

  20. The spiral arms of the Milky Way: The relative location of each different arm tracer within a typical spiral arm width

    Energy Technology Data Exchange (ETDEWEB)

    Vallée, Jacques P., E-mail: jacques.vallee@nrc-cnrc.gc.ca [National Research Council Canada, National Science Infrastructure portfolio, Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, B.C., V9E 2E7 (Canada)

    2014-07-01

    From the Sun's location in the Galactic disk, different arm tracers (CO, H I, hot dust, etc.) have been employed to locate a tangent to each spiral arm. Using all various and different observed spiral arm tracers (as published elsewhere), we embark on a new goal, namely the statistical analysis of these published data (data mining) to statistically compute the mean location of each spiral arm tracer. We show for a typical arm cross-cut, a separation of 400 pc between the mid-arm and the dust lane (at the inner edge of the arm, toward the Galactic center). Are some arms major and others minor? Separating arms into two sets, as suggested by some, we find the same arm widths between the two sets. Our interpretation is that we live in a multiple (four-arm) spiral (logarithmic) pattern (around a pitch angle of 12°) for the stars and gas in the Milky Way, with a sizable interarm separation (around 3 kpc) at the Sun's location and the same arm width for each arm (near 400 pc from mid-arm to dust lane).

  1. The spiral arms of the Milky Way: The relative location of each different arm tracer within a typical spiral arm width

    International Nuclear Information System (INIS)

    Vallée, Jacques P.

    2014-01-01

    From the Sun's location in the Galactic disk, different arm tracers (CO, H I, hot dust, etc.) have been employed to locate a tangent to each spiral arm. Using all various and different observed spiral arm tracers (as published elsewhere), we embark on a new goal, namely the statistical analysis of these published data (data mining) to statistically compute the mean location of each spiral arm tracer. We show for a typical arm cross-cut, a separation of 400 pc between the mid-arm and the dust lane (at the inner edge of the arm, toward the Galactic center). Are some arms major and others minor? Separating arms into two sets, as suggested by some, we find the same arm widths between the two sets. Our interpretation is that we live in a multiple (four-arm) spiral (logarithmic) pattern (around a pitch angle of 12°) for the stars and gas in the Milky Way, with a sizable interarm separation (around 3 kpc) at the Sun's location and the same arm width for each arm (near 400 pc from mid-arm to dust lane).

  2. BWR 9 X 9 Fuel Assembly Thermal-Hydraulic Tests (2): Hydraulic Vibration Test

    International Nuclear Information System (INIS)

    Yoshiaki Tsukuda; Katsuichiro Kamimura; Toshiitsu Hattori; Akira Tanabe; Noboru Saito; Masahiko Warashina; Yuji Nishino

    2002-01-01

    Nuclear Power Engineering Corporation (NUPEC) conducted thermal-hydraulic projects for verification of thermal-hydraulic design reliability for BWR high-burnup 8 x 8 and 9 x 9 fuel assemblies, entrusted by the Ministry of Economy, Trade and Industry (METI). As a part of the NUPEC thermal-hydraulic projects, hydraulic vibration tests using full-scale test assemblies simulating 9 x 9 fuel assemblies were carried out to evaluate BWR fuel integrity. The test data were applied to development of a new correlation for the estimation of fuel rod vibration amplitude. (authors)

  3. EVALUATING CONTINUOUS-TIME SLAM USING A PREDEFINED TRAJECTORY PROVIDED BY A ROBOTIC ARM

    Directory of Open Access Journals (Sweden)

    B. Koch

    2017-09-01

    Full Text Available Recently published approaches to SLAM algorithms process laser sensor measurements and output a map as a point cloud of the environment. Often the actual precision of the map remains unclear, since SLAMalgorithms apply local improvements to the resulting map. Unfortunately, it is not trivial to compare the performance of SLAMalgorithms objectively, especially without an accurate ground truth. This paper presents a novel benchmarking technique that allows to compare a precise map generated with an accurate ground truth trajectory to a map with a manipulated trajectory which was distorted by different forms of noise. The accurate ground truth is acquired by mounting a laser scanner on an industrial robotic arm. The robotic arm is moved on a predefined path while the position and orientation of the end-effector tool are monitored. During this process the 2D profile measurements of the laser scanner are recorded in six degrees of freedom and afterwards used to generate a precise point cloud of the test environment. For benchmarking, an offline continuous-time SLAM algorithm is subsequently applied to remove the inserted distortions. Finally, it is shown that the manipulated point cloud is reversible to its previous state and is slightly improved compared to the original version, since small errors that came into account by imprecise assumptions, sensor noise and calibration errors are removed as well.

  4. Evaluating Continuous-Time Slam Using a Predefined Trajectory Provided by a Robotic Arm

    Science.gov (United States)

    Koch, B.; Leblebici, R.; Martell, A.; Jörissen, S.; Schilling, K.; Nüchter, A.

    2017-09-01

    Recently published approaches to SLAM algorithms process laser sensor measurements and output a map as a point cloud of the environment. Often the actual precision of the map remains unclear, since SLAMalgorithms apply local improvements to the resulting map. Unfortunately, it is not trivial to compare the performance of SLAMalgorithms objectively, especially without an accurate ground truth. This paper presents a novel benchmarking technique that allows to compare a precise map generated with an accurate ground truth trajectory to a map with a manipulated trajectory which was distorted by different forms of noise. The accurate ground truth is acquired by mounting a laser scanner on an industrial robotic arm. The robotic arm is moved on a predefined path while the position and orientation of the end-effector tool are monitored. During this process the 2D profile measurements of the laser scanner are recorded in six degrees of freedom and afterwards used to generate a precise point cloud of the test environment. For benchmarking, an offline continuous-time SLAM algorithm is subsequently applied to remove the inserted distortions. Finally, it is shown that the manipulated point cloud is reversible to its previous state and is slightly improved compared to the original version, since small errors that came into account by imprecise assumptions, sensor noise and calibration errors are removed as well.

  5. Rosie: A mobile worksystem for decontamination and dismantlement operations

    International Nuclear Information System (INIS)

    Thompson, B.R.; Conley, L.

    1996-01-01

    RedZone Robotics, Inc. and Carnegie Mellon University's Field Robotics Center have undertaken a contract to develop a next-generation worksystem for decommissioning and dismantlement tasks in Department of Energy (DOE) facilities. Currently, the authors are closing the second phase of this three phase effort and have completed the design and fabrication of the worksystem: Rosie. Rosie includes a locomotor, heavy manipulator, control center, and control system for robot operation. The locomotor is an omni-directional platform with tether management and hydraulic power capabilities. The heavy manipulator is a high-payload, long-reach system intended to deploy tools into the work area. The heavy manipulator is capable of deploying systems such as the Dual-Arm Work Module--a five degree-of-freedom platform supporting two highly dexterous manipulators--or a single manipulator for performing simpler, less dexterous tasks. Rosie is telerobotic to the point of having servo-controlled motions which can be operated and coordinated through the control center

  6. Research on the man in the loop control system of the robot arm based on gesture control

    Science.gov (United States)

    Xiao, Lifeng; Peng, Jinbao

    2017-03-01

    The Man in the loop control system of the robot arm based on gesture control research complex real-world environment, which requires the operator to continuously control and adjust the remote manipulator, as the background, completes the specific mission human in the loop entire system as the research object. This paper puts forward a kind of robot arm control system of Man in the loop based on gesture control, by robot arm control system based on gesture control and Virtual reality scene feedback to enhance immersion and integration of operator, to make operator really become a part of the whole control loop. This paper expounds how to construct a man in the loop control system of the robot arm based on gesture control. The system is a complex system of human computer cooperative control, but also people in the loop control problem areas. The new system solves the problems that the traditional method has no immersion feeling and the operation lever is unnatural, the adjustment time is long, and the data glove mode wears uncomfortable and the price is expensive.

  7. Use of a robotic manipulator in the simulation of the automation of a calibration process of dosemeters

    International Nuclear Information System (INIS)

    Benitez R, J.S.; Najera H, M.C.

    2002-01-01

    The development of a system based in a manipulative robot which simulates the operative sequence in a calibration process of dosemeters is presented. In this process it is performed the monitoring of the dosemeter positions and the calibrator by mean of an arm of articulated robot which develops the movement sequences and the taking a decision based on the information coming from the external sensors. (Author)

  8. Fusion of Haptic and Gesture Sensors for Rehabilitation of Bimanual Coordination and Dexterous Manipulation.

    Science.gov (United States)

    Yu, Ningbo; Xu, Chang; Li, Huanshuai; Wang, Kui; Wang, Liancheng; Liu, Jingtai

    2016-03-18

    Disabilities after neural injury, such as stroke, bring tremendous burden to patients, families and society. Besides the conventional constrained-induced training with a paretic arm, bilateral rehabilitation training involves both the ipsilateral and contralateral sides of the neural injury, fitting well with the fact that both arms are needed in common activities of daily living (ADLs), and can promote good functional recovery. In this work, the fusion of a gesture sensor and a haptic sensor with force feedback capabilities has enabled a bilateral rehabilitation training therapy. The Leap Motion gesture sensor detects the motion of the healthy hand, and the omega.7 device can detect and assist the paretic hand, according to the designed cooperative task paradigm, as much as needed, with active force feedback to accomplish the manipulation task. A virtual scenario has been built up, and the motion and force data facilitate instantaneous visual and audio feedback, as well as further analysis of the functional capabilities of the patient. This task-oriented bimanual training paradigm recruits the sensory, motor and cognitive aspects of the patient into one loop, encourages the active involvement of the patients into rehabilitation training, strengthens the cooperation of both the healthy and impaired hands, challenges the dexterous manipulation capability of the paretic hand, suits easy of use at home or centralized institutions and, thus, promises effective potentials for rehabilitation training.

  9. Fusion of Haptic and Gesture Sensors for Rehabilitation of Bimanual Coordination and Dexterous Manipulation

    Directory of Open Access Journals (Sweden)

    Ningbo Yu

    2016-03-01

    Full Text Available Disabilities after neural injury, such as stroke, bring tremendous burden to patients, families and society. Besides the conventional constrained-induced training with a paretic arm, bilateral rehabilitation training involves both the ipsilateral and contralateral sides of the neural injury, fitting well with the fact that both arms are needed in common activities of daily living (ADLs, and can promote good functional recovery. In this work, the fusion of a gesture sensor and a haptic sensor with force feedback capabilities has enabled a bilateral rehabilitation training therapy. The Leap Motion gesture sensor detects the motion of the healthy hand, and the omega.7 device can detect and assist the paretic hand, according to the designed cooperative task paradigm, as much as needed, with active force feedback to accomplish the manipulation task. A virtual scenario has been built up, and the motion and force data facilitate instantaneous visual and audio feedback, as well as further analysis of the functional capabilities of the patient. This task-oriented bimanual training paradigm recruits the sensory, motor and cognitive aspects of the patient into one loop, encourages the active involvement of the patients into rehabilitation training, strengthens the cooperation of both the healthy and impaired hands, challenges the dexterous manipulation capability of the paretic hand, suits easy of use at home or centralized institutions and, thus, promises effective potentials for rehabilitation training.

  10. THE EFFECT OF LONG-TERM BIMANUAL TRAINING ON ARM SELECTION DURING REACHING TASKS

    OpenAIRE

    Akpinar, Selcuk

    2015-01-01

    Handedness is viewed either as a preference or an asymmetry in sensorimotor performance. It has been shown that there is a relation between sensorimotor performance and hand selection. This relation is affected by the manipulation of sensory feedback, suggesting an effect of task condition on hand selection, and by a unimanual athletic training. Thus, in the current study, the aim was to find out if arm selection and symmetry were affected by a long-term bimanual practice with respect to moto...

  11. A Non-linear Model for Predicting Tip Position of a Pliable Robot Arm Segment Using Bending Sensor Data

    Directory of Open Access Journals (Sweden)

    Elizabeth I. SKLAR

    2016-04-01

    Full Text Available Using pliable materials for the construction of robot bodies presents new and interesting challenges for the robotics community. Within the EU project entitled STIFFness controllable Flexible & Learnable manipulator for surgical Operations (STIFF-FLOP, a bendable, segmented robot arm has been developed. The exterior of the arm is composed of a soft material (silicone, encasing an internal structure that contains air-chamber actuators and a variety of sensors for monitoring applied force, position and shape of the arm as it bends. Due to the physical characteristics of the arm, a proper model of robot kinematics and dynamics is difficult to infer from the sensor data. Here we propose a non-linear approach to predicting the robot arm posture, by training a feed-forward neural network with a structured series of pressures values applied to the arm's actuators. The model is developed across a set of seven different experiments. Because the STIFF-FLOP arm is intended for use in surgical procedures, traditional methods for position estimation (based on visual information or electromagnetic tracking will not be possible to implement. Thus the ability to estimate pose based on data from a custom fiber-optic bending sensor and accompanying model is a valuable contribution. Results are presented which demonstrate the utility of our non-linear modelling approach across a range of data collection procedures.

  12. Electrothermal modeling, fabrication and analysis of low-power consumption thermal actuator with buckling arm

    KAUST Repository

    So, Hongyun

    2013-10-31

    © 2013, Springer-Verlag Berlin Heidelberg. This paper reports on a novel thermal actuator with sub-micron metallic structures and a buckling arm to operate with low voltages and to generate very large deflections, respectively. A lumped electrothermal model and analysis were also developed to validate the mechanical design and easily predict the temperature distribution along arms of the sub-micron actuator. The actuator was fabricated via the combination of electron beam lithography to form actuator arms with a minimum feature size of 200 nm and lift-off process to deposit a high aspect ratio nickel structure. Reproducible displacements of up to 1.9 μm at the tip were observed up to 250 mV under confocal microscope. The experimentally measured deflection values and theoretically calculated temperature distribution by the developed model were compared with finite element analysis results and they were in good agreement. This study shows a promising approach to develop more sophisticated nano actuators required larger deflections for manipulation of sub-micron scale objects with low-power consumption.

  13. Electromigration of Contaminated Soil by Electro-Bioremediation Technique

    Science.gov (United States)

    Azhar, A. T. S.; Nabila, A. T. A.; Nurshuhaila, M. S.; Shaylinda, M. Z. N.; Azim, M. A. M.

    2016-07-01

    Soil contamination with heavy metals poses major environmental and human health problems. This problem needs an efficient method and affordable technological solution such as electro-bioremediation technique. The electro-bioremediation technique used in this study is the combination of bacteria and electrokinetic process. The aim of this study is to investigate the effectiveness of Pseudomonas putida bacteria as a biodegradation agent to remediate contaminated soil. 5 kg of kaolin soil was spiked with 5 g of zinc oxide. During this process, the anode reservoir was filled with Pseudomonas putida while the cathode was filled with distilled water for 5 days at 50 V of electrical gradient. The X-Ray Fluorescent (XRF) test indicated that there was a significant reduction of zinc concentration for the soil near the anode with 89% percentage removal. The bacteria count is high near the anode which is 1.3x107 cfu/gww whereas the bacteria count at the middle and near the cathode was 5.0x106 cfu/gww and 8.0x106 cfu/gww respectively. The migration of ions to the opposite charge of electrodes during the electrokinetic process resulted from the reduction of zinc. The results obtained proved that the electro-bioremediation reduced the level of contaminants in the soil sample. Thus, the electro-bioremediation technique has the potential to be used in the treatment of contaminated soil.

  14. Application of Electro Chemical Machining for materials used in extreme conditions

    Science.gov (United States)

    Pandilov, Z.

    2018-03-01

    Electro-Chemical Machining (ECM) is the generic term for a variety of electrochemical processes. ECM is used to machine work pieces from metal and metal alloys irrespective of their hardness, strength or thermal properties, through the anodic dissolution, in aerospace, automotive, construction, medical equipment, micro-systems and power supply industries. The Electro Chemical Machining is extremely suitable for machining of materials used in extreme conditions. General overview of the Electro-Chemical Machining and its application for different materials used in extreme conditions is presented.

  15. Recent highlights in electro-driven separations- selected applications of alkylthiol gold nanoparticles in capillary electrophoresis and capillary electro-chromatography.

    Science.gov (United States)

    Guihen, Elizabeth

    2017-09-01

    To date, alkylthiol gold nanoparticles (AuNPs) have been widely used in electro-chromatographic separation techniques as a viable alternative to traditional stationary phases. This is mainly due to their stability, chemical inertness, ease of functionality, increased phase ratio, ability to form self-assembled monolayers. They also yield versatile stationary phases with highly specific targeted functionalities. At the nanoscale region, the chemical and physical properties of a molecule display different attributes to that of the parent molecules or material, hence these features can be harnessed in electro-driven chromatographic separations. Application areas illustrating the use of AuNPs in separation science continue to grow and expand to cover many different kinds of analysis. The last decade has witnessed a successful trend in miniaturisation of chemical separation systems toward the micro and nanoscale ranges. Nanoparticle-based stationary phases fit well with performing chemical separations on microfluidic and capillary platforms. In this review the theory of the use of alkylthiol gold nanoparticles in electro-chromatographic driven separation methods will be discussed. This will be followed by details of recent and selected applications showing alkylthiol gold nanoparticles in capillary electrophoretic and open-tubular electro-chromatographic separations. This review will focus solely on alkylthiol based gold nanoparticles, therefore other kinds of chemical moieties bonded to gold nanoparticles are outside the scope of this review. Finally the future outlook of this exciting technology will be outlined in some detail in the final section. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Power Management in Mobile Hydraulic Applications - An Approach for Designing Hydraulic Power Supply Systems

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen

    2004-01-01

    Throughout the last three decades energy consumption has become one of the primary design aspects in hydraulic systems, especially for mobile hydraulic systems, as power and cooling capacity here is at limited disposal. Considering the energy usage, this is dependent on component efficiency, but ...... the hydraulic power supply in the most energy efficient way, when considering a number of load situations. Finally an example of the approach is shown to prove its validity.}......Throughout the last three decades energy consumption has become one of the primary design aspects in hydraulic systems, especially for mobile hydraulic systems, as power and cooling capacity here is at limited disposal. Considering the energy usage, this is dependent on component efficiency...

  17. The study of dynamics and strength of hydraulic crane-manipulating installations on a movable chassis

    Directory of Open Access Journals (Sweden)

    Lagerev A.V.

    2015-10-01

    Full Text Available The modified version of previously reviewed technique for dynamics and stress analysis of fixed-base manipulators (articulating cranes is suggested. The idea is to insert a fictitious six-degrees-of-freedom joint between a fixed support and manipulator’s base thus eliminating fixed base motion constraints. The technique has been implemented in the software package KBCrane and used for dynamics and stress analysis of an articulating crane mounted on a ship rocking in waves. Based on the results of simulation the distribution and level of stress in the crane is estimated.

  18. Optical and electro-optic anisotropy of epitaxial PZT thin films

    Science.gov (United States)

    Zhu, Minmin; Du, Zehui; Jing, Lin; Yoong Tok, Alfred Iing; Tong Teo, Edwin Hang

    2015-07-01

    Strong optical and electro-optic (EO) anisotropy has been investigated in ferroelectric Pb(Zr0.48Ti0.52)O3 thin films epitaxially grown on Nb-SrTiO3 (001), (011), and (111) substrates using magnetron sputtering. The refractive index, electro-optic, and ferroelectric properties of the samples demonstrate the significant dependence on the growth orientation. The linear electro-optic coefficients of the (001), (011), and (111)-oriented PZT thin films were 270.8, 198.8, and 125.7 pm/V, respectively. Such remarkable anisotropic EO behaviors have been explained according to the structure correlation between the orientation dependent distribution, spontaneous polarization, epitaxial strain, and domain pattern.

  19. Hydraulic Yaw System

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Mørkholt, M.

    a hydraulic soft yaw system, which is able to reduce the loads on the wind turbine significantly. A full scale hydraulic yaw test rig is available for experiments and tests. The test rig is presented as well as the system schematics of the hydraulic yaw system....... the HAWC2 aeroelastic code and an extended model of the NREL 5MW turbine combined with a simplified linear model of the turbine, the parameters of the soft yaw system are optimized to reduce loading in critical components. Results shows that a significant reduction in fatigue and extreme loads to the yaw...... system and rotor shaft when utilizing the soft yaw drive concept compared to the original stiff yaw system. The physical demands of the hydraulic yaw system are furthermore examined for a life time of 20 years. Based on the extrapolated loads, the duty cycles show that it is possible to construct...

  20. Chaotic micromixer utilizing electro-osmosis and induced charge electro-osmosis in eccentric annulus

    International Nuclear Information System (INIS)

    Feng, Huicheng; Wong, Teck Neng; Marcos; Che, Zhizhao

    2016-01-01

    Efficient mixing is of significant importance in numerous chemical and biomedical applications but difficult to realize rapidly in microgeometries due to the lack of turbulence. We propose to enhance mixing by introducing Lagrangian chaos through electro-osmosis (EO) or induced charge electro-osmosis (ICEO) in an eccentric annulus. The analysis reveals that the created Lagrangian chaos can achieve a homogeneous mixing much more rapidly than either the pure EO or the pure ICEO. Our systematic investigations on the key parameters, ranging from the eccentricity, the alternating time period, the number of flow patterns in one time period, to the specific flow patterns utilized for the Lagrangian chaos creation, present that the Lagrangian chaos is considerably robust. The system can obtain a good mixing effect with wide ranges of eccentricity, alternating time period, and specific flow patterns utilized for the Lagrangian chaos creation as long as the number of flow patterns in one time period is two. As the electric field increases, the time consumption for homogenous mixing is reduced more remarkably for the Lagrangian chaos of the ICEO than that of the EO.