WorldWideScience

Sample records for protection system actuation

  1. Annexes to the lecture on reactor protection system including engineered features actuation system

    International Nuclear Information System (INIS)

    Palmaers, W.

    1982-01-01

    The present paper deals with the fundamentals for a reactor protection system and discusses the following topics: - System lay-out - Analog measured data acquisition - Analog measured data processing - Limit value generation and logical gating - Procesing of the reactor protection actuation signals - Decoupling of the reactor protection system - Mechanical lay-out - Monitoring system and - Emergency control station. (orig./RW)

  2. Evaluation of Generic Issue 57: Effects of fire protection system actuation on safety-related equipment

    International Nuclear Information System (INIS)

    Lambright, J.; Bohn, M.; Lynch, J.; Ross, S.; Brosseau, D.

    1992-12-01

    Nuclear power plants have experienced actuations of fire protection systems (FPSs) under conditions for which these systems were not intended to actuate and also have experienced advertent actuations with the presence of a fire. These actuations have often damaged safety-related equipment. A review of the impact of past occurrences of both types of such events and their impact on plant safety systems, an analysis of the risk impacts of such events on nuclear power plant safety, and a cost-benefit analysis of potential corrective measures have been performed. Thirteen different scenarios leading to actuation of fire protection systems due to a variety of causes were identified. These scenarios ranged from inadvertent actuation caused by human error to hardware failure, and include seismic root causes and seismic/fire interactions. A quantification of these thirteen root causes, where applicable, was performed on generically applicable scenarios. This document, Volume 4, contains appendices E and F of this report

  3. Reactor protection system including engineered features actuation system

    International Nuclear Information System (INIS)

    Palmaers, W.

    1982-01-01

    The safety concept requires to ensure that - the reactor protection system - the active engineered safeguard - and the necessary auxiliary systems are so designed and interfaced in respect of design and mode of action that, in the event of single component failure reliable control of the consequences of accidents remains ensured at all times and that the availability of the power plant is not limited unnecessarily. In order to satisfy these requirements due, importance was attached to a consistent spacial separation of the mutually redundant subsystems of the active safety equipment. The design and layout of the reactor protection system, of the power supply (emergency power supply), and of the auxiliary systems important from the safety engineering point of view, are such that their subsystems also largely satisfy the requirements of independence and spacial separation. (orig./RW)

  4. Logical safety system for triggering off the protection action of a safety actuator

    International Nuclear Information System (INIS)

    Plaige, Yves.

    1982-01-01

    This invention applies in particular to the emergency triggering of safety actuators controlling the shutdown of a nuclear reactor. This logical safety system includes four redundant lines each composed, inter alia, of a logical circuit for controlling the triggering of a protection action, a logical alarm circuit connected to the control circuit and a logical inhibiting circuit making it impossible to inhibit several alarm circuits simultaneously [fr

  5. Flight control actuation system

    Science.gov (United States)

    Wingett, Paul T. (Inventor); Gaines, Louie T. (Inventor); Evans, Paul S. (Inventor); Kern, James I. (Inventor)

    2006-01-01

    A flight control actuation system comprises a controller, electromechanical actuator and a pneumatic actuator. During normal operation, only the electromechanical actuator is needed to operate a flight control surface. When the electromechanical actuator load level exceeds 40 amps positive, the controller activates the pneumatic actuator to offset electromechanical actuator loads to assist the manipulation of flight control surfaces. The assistance from the pneumatic load assist actuator enables the use of an electromechanical actuator that is smaller in size and mass, requires less power, needs less cooling processes, achieves high output forces and adapts to electrical current variations. The flight control actuation system is adapted for aircraft, spacecraft, missiles, and other flight vehicles, especially flight vehicles that are large in size and travel at high velocities.

  6. Firewater system inadvertent actuation frequencies

    International Nuclear Information System (INIS)

    Schroeder, J.A.; Eide, S.A.

    1993-01-01

    This paper presents some recommended generic values for fire protection system inadvertent actuation frequencies. The frequencies are based on actual data from Department of Energy and commercial reactor plant facilities

  7. Regulatory analysis for the resolution of generic issue 57: Effects of Fire Protection System Actuation on Safety-Related Equipment

    International Nuclear Information System (INIS)

    Woods, H.W.

    1993-10-01

    Actuation of Fire Protection Systems (FPS) in Nuclear Power Plants have resulted in adverse interactions with equipment important to safety. Precursor operational experience has shown that 37% of all FPS actuations damaged some equipment, and 20% of all FPS actuations have resulted in a plant transient and reactor trip. On an average 0.17 FPS actuations per reactor year have been experienced in nuclear power plants in this country. This report presents the regulatory analysis for GI-57, ''Effects of Fire Protection System Actuation on Safety-Related Equipment''. The risk reduction estimates, cost/benefit analyses, and other insights gained during this effort have shown that implementation of the recommendations contained in this report can significantly reduce risk, and that these improvements can be warranted in accordance with the backfit rule, 10 CFR 50.109(a)(3). However, plant specific analyses are required in order to identify such improvements. Generic analyses can not serve to identify improvements that could be warranted for individual, specific plants. Plant specific analyses of the type needed for this purpose are underway as part of the Individual Plant Examination of External Events (IPEEE) program

  8. Suitability review of FMEA and reliability analysis for digital plant protection system and digital engineered safety features actuation system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, I. S.; Kim, T. K.; Kim, M. C.; Kim, B. S.; Hwang, S. W.; Ryu, K. C. [Hanyang Univ., Seoul (Korea, Republic of)

    2000-11-15

    Of the many items that should be checked out during a review stage of the licensing application for the I and C system of Ulchin 5 and 6 units, this report relates to a suitability review of the reliability analysis of Digital Plant Protection System (DPPS) and Digital Engineered Safety Features Actuation System (DESFAS). In the reliability analysis performed by the system designer, ABB-CE, fault tree analysis was used as the main methods along with Failure Modes and Effect Analysis (FMEA). However, the present regulatory technique dose not allow the system reliability analysis and its results to be appropriately evaluated. Hence, this study was carried out focusing on the following four items ; development of general review items by which to check the validity of a reliability analysis, and the subsequent review of suitability of the reliability analysis for Ulchin 5 and 6 DPPS and DESFAS L development of detailed review items by which to check the validity of an FMEA, and the subsequent review of suitability of the FMEA for Ulchin 5 and 6 DPPS and DESFAS ; development of detailed review items by which to check the validity of a fault tree analysis, and the subsequent review of suitability of the fault tree for Ulchin 5 and 6 DPPS and DESFAS ; an integrated review of the safety and reliability of the Ulchin 5 and 6 DPPS and DESFAS based on the results of the various reviews above and also of a reliability comparison between the digital systems and the comparable analog systems, i.e., and analog Plant Protection System (PPS) and and analog Engineered Safety Features Actuation System (ESFAS). According to the review mentioned above, the reliability analysis of Ulchin 5 and 6 DPPS and DESFAS generally satisfies the review requirements. However, some shortcomings of the analysis were identified in our review such that the assumed test periods for several equipment were not properly incorporated in the analysis, and failures of some equipment were not included in the

  9. Actuator System with Dual Chambers

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to an actuator system with a magnetic lead screw (50), comprises a magnetic rotor (5) and a translator cylinder (2), the translator cylinder (2) comprises a magnetic stator (16), the translator cylinder (2) has a closed first end (14) and a second end confined by a lid...... volume, wherein the first volume and the second volume changes as a function of the linear movement. The invention also relates to a method of operating an actuator system with a magnetic lead screw....

  10. Magnetic Actuation of Biological Systems

    Science.gov (United States)

    Lauback, Stephanie D.

    Central to the advancement of many biomedical and nanotechnology capabilities is the capacity to precisely control the motion of micro and nanostructures. These applications range from single molecule experiments to cell isolation and separation, to drug delivery and nanomachine manipulation. This dissertation focuses on actuation of biological micro- and nano-entities through the use of weak external magnetic fields, superparamagnetic beads, and ferromagnetic thin films. The magnetic platform presents an excellent method for actuation of biological systems due to its ability to directly control the motion of an array of micro and nanostructures in real-time with calibrated picoNewton forces. The energy landscape of two ferromagnetic thin film patterns (disks and zigzag wires) is experimentally explored and compared to corresponding theoretical models to quantify the applied forces and trajectories of superparamagnetic beads due to the magnetic traps. A magnetic method to directly actuate DNA nanomachines in real-time with nanometer resolution and sub-second response times using micromagnetic control was implemented through the use of stiff DNA micro-levers which bridged the large length scale mismatch between the micro-actuator and the nanomachine. Compared to current alternative methods which are limited in the actuation speeds and the number of reconfiguration states of DNA constructs, this magnetic approach enables fast actuation (˜ milliseconds) and reconfigurable conformations achieved through a continuous range of finely tuned steps. The system was initially tested through actuation of the stiff arm tethered to the surface, and two prototype DNA nanomachines (rotor and hinge) were successfully actuated using the stiff mechanical lever. These results open new possibilities in the development of functional robotic systems at the molecular scale. In exploiting the use of DNA stiff levers, a new technique was also developed to investigate the emergence of the

  11. Reliable actuators for twin rotor MIMO system

    Science.gov (United States)

    Rao, Vidya S.; V. I, George; Kamath, Surekha; Shreesha, C.

    2017-11-01

    Twin Rotor MIMO System (TRMS) is a bench mark system to test flight control algorithms. One of the perturbations on TRMS which is likely to affect the control system is actuator failure. Therefore, there is a need for a reliable control system, which includes H infinity controller along with redundant actuators. Reliable control refers to the design of a control system to tolerate failures of a certain set of actuators or sensors while retaining desired control system properties. Output of reliable controller has to be transferred to the redundant actuator effectively to make the TRMS reliable even under actual actuator failure.

  12. 30 CFR 75.1103-6 - Automatic fire sensors; actuation of fire suppression systems.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Automatic fire sensors; actuation of fire... Protection § 75.1103-6 Automatic fire sensors; actuation of fire suppression systems. Point-type heat sensors or automatic fire sensor and warning device systems may be used to actuate deluge-type water systems...

  13. Choosing Actuators for Automatic Control Systems of Thermal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Gorbunov, A. I., E-mail: gor@tornado.nsk.ru [JSC “Tornado Modular Systems” (Russian Federation); Serdyukov, O. V. [Siberian Branch of the Russian Academy of Sciences, Institute of Automation and Electrometry (Russian Federation)

    2015-03-15

    Two types of actuators for automatic control systems of thermal power plants are analyzed: (i) pulse-controlled actuator and (ii) analog-controlled actuator with positioning function. The actuators are compared in terms of control circuit, control accuracy, reliability, and cost.

  14. A magnetorheological actuation system: test and model

    International Nuclear Information System (INIS)

    John, Shaju; Chaudhuri, Anirban; Wereley, Norman M

    2008-01-01

    Self-contained actuation systems, based on frequency rectification of the high frequency motion of an active material, can produce high force and stroke output. Magnetorheological (MR) fluids are active fluids whose rheological properties can be altered by the application of a magnetic field. By using MR fluids as the energy transmission medium in such hybrid devices, a valving system with no moving parts can be implemented and used to control the motion of an output cylinder shaft. The MR fluid based valves are configured in the form of an H-bridge to produce bi-directional motion in an output cylinder by alternately applying magnetic fields in the two opposite arms of the bridge. The rheological properties of the MR fluid are modeled using both Bingham plastic and bi-viscous models. In this study, the primary actuation is performed using a compact terfenol-D rod driven pump and frequency rectification of the rod motion is done using passive reed valves. The pump and reed valve configuration along with MR fluidic valves form a compact hydraulic actuation system. Actuator design, analysis and experimental results are presented in this paper. A time domain model of the actuator is developed and validated using experimental data

  15. A wireless actuating drug delivery system

    International Nuclear Information System (INIS)

    Jo, Won-Jun; Baek, Seung-Ki; Park, Jung-Hwan

    2015-01-01

    A wireless actuating drug delivery system was devised. The system is based on induction heating for drug delivery. In this study, thermally generated nitrogen gas produced by induction heating of azobisisobutyronitrile (AIBN) was utilized for pressure-driven release of the drug. The delivery device consists of an actuator chamber, a drug reservoir, and a microchannel. A semicircular copper disc (5 and 6 mm in diameter and 100 µm thick), and thermal conductive tape were integrated as the heating element in the actuator chamber. The final device was 2.7 mm thick. 28 µl of drug solution were placed in the reservoir and the device released the drug quickly at the rate of 6 µl s −1 by induction heating at 160 µT of magnetic intensity. The entire drug solution was released and dispersed after subcutaneous implantation under identical experimental condition. This study demonstrates that the device was simply prepared and drug delivery could be achieved by wireless actuation of a thin, pressure-driven actuator. (paper)

  16. 14 CFR 33.72 - Hydraulic actuating systems.

    Science.gov (United States)

    2010-01-01

    ... AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.72 Hydraulic actuating systems. Each hydraulic actuating system must function properly under all conditions in which the... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic actuating systems. 33.72 Section...

  17. Bio-Inspired Flexible Cellular Actuating Systems

    Science.gov (United States)

    2013-11-21

    S. Hong, “Robust adaptive boundary control of a flexible marine riser with vessel dynamics,” Automatica, vol. 47, pp. 722–732, 2011. [22] D. H...conditionally accepted. [6] W. He, S. S. Ge, B. V. E. How, Y. S. Choo, and K. S. Hong, “Robust adaptive boundary control of a flexible marine riser ... flexible robotic actuators, often represented by a distributed parameter system or a partial differential equation. We establish a model-guided

  18. Bioinspired pressure actuated adhesive system

    NARCIS (Netherlands)

    Paretkar, D.R.; Kamperman, M.M.G.; Schneider, A.S.; Martina, D.; Creton, C.; Arzt, E.

    2011-01-01

    We developed a dry synthetic adhesive system inspired by gecko feet adhesion that can switch reversibly from adhesion to non-adhesion with applied pressure as external stimulus. Micropatterned polydimethylsiloxane (PDMS) surfaces with pillars of 30 µm length and 10 µm diameter were fabricated using

  19. Valve system incorporating single failure protection logic

    Science.gov (United States)

    Ryan, Rodger; Timmerman, Walter J. H.

    1980-01-01

    A valve system incorporating single failure protective logic. The system consists of a valve combination or composite valve which allows actuation or de-actuation of a device such as a hydraulic cylinder or other mechanism, integral with or separate from the valve assembly, by means of three independent input signals combined in a function commonly known as two-out-of-three logic. Using the input signals as independent and redundant actuation/de-actuation signals, a single signal failure, or failure of the corresponding valve or valve set, will neither prevent the desired action, nor cause the undesired action of the mechanism.

  20. Microelectromechanical systems integrating molecular spin crossover actuators

    Energy Technology Data Exchange (ETDEWEB)

    Manrique-Juarez, Maria D. [LCC, CNRS and Université de Toulouse, UPS, INP, F-31077 Toulouse (France); LAAS, CNRS and Université de Toulouse, INSA, UPS, F-31077 Toulouse (France); Rat, Sylvain; Salmon, Lionel; Molnár, Gábor; Bousseksou, Azzedine, E-mail: liviu.nicu@laas.fr, E-mail: azzedine.bousseksou@lcc-toulouse.fr [LCC, CNRS and Université de Toulouse, UPS, INP, F-31077 Toulouse (France); Mathieu, Fabrice; Saya, Daisuke; Séguy, Isabelle; Leïchlé, Thierry; Nicu, Liviu, E-mail: liviu.nicu@laas.fr, E-mail: azzedine.bousseksou@lcc-toulouse.fr [LAAS, CNRS and Université de Toulouse, INSA, UPS, F-31077 Toulouse (France)

    2016-08-08

    Silicon MEMS cantilevers coated with a 200 nm thin layer of the molecular spin crossover complex [Fe(H{sub 2}B(pz){sub 2}){sub 2}(phen)] (H{sub 2}B(pz){sub 2} = dihydrobis(pyrazolyl)borate and phen = 1,10-phenantroline) were actuated using an external magnetic field and their resonance frequency was tracked by means of integrated piezoresistive detection. The light-induced spin-state switching of the molecules from the ground low spin to the metastable high spin state at 10 K led to a well-reproducible shift of the cantilever's resonance frequency (Δf{sub r} = −0.52 Hz). Control experiments at different temperatures using coated as well as uncoated devices along with simple calculations support the assignment of this effect to the spin transition. This latter translates into changes in mechanical behavior of the cantilever due to the strong spin-state/lattice coupling. A guideline for the optimization of device parameters is proposed so as to efficiently harness molecular scale movements for large-scale mechanical work, thus paving the road for nanoelectromechanical systems (NEMS) actuators based on molecular materials.

  1. Overview of Actuated Arm Support Systems and Their Applications

    Directory of Open Access Journals (Sweden)

    E.A. Lomonova

    2013-10-01

    Full Text Available Arm support systems provide support throughout daily tasks, training or in an industrial environment. During the last decades a large diversity of actuated arm support systems have been developed. To analyze the actuation principles in these systems, an overview of actuated arm support systems is provided. This overview visualizes the current trends on research and development of these support systems and distinguishes three categories. These categories depend mainly on the functional status of the user environment, which defines the specifications. Therefore, the actuated arm support systems are classified according to their user environment, namely: ambulatory, rehabilitation and industrial. Furthermore, three main actuation principles and three mechanical construction principles have been identified.

  2. Linear Actuator System for the NASA Docking System

    Science.gov (United States)

    Dick, Brandon N.; Oesch, Christopher; Rupp, Timothy W.

    2017-01-01

    The Linear Actuator System (LAS) is a major sub-system within the NASA Docking System (NDS). The NDS Block 1 will be used on the Boeing Crew Space Transportation (CST-100) system to achieve docking with the International Space Station. Critical functions in the Soft Capture aspect of docking are performed by the LAS. This paper describes the general function of the LAS, the system's key requirements and technical challenges, and the development and qualification approach for the system.

  3. A system look at electromechanical actuation for primary flight control

    NARCIS (Netherlands)

    Lomonova, E.A.

    1997-01-01

    An overview is presented of the emergence of the ALL Electric flight control system (FCS) or power-by-wire (PBW) concept. The concept of fly-by-power refers to the actuator using electrical rather than hydraulic power. The development of the primary flight control Electromechanical Actuators (EMAs)

  4. Stability and stabilization of linear systems with saturating actuators

    CERN Document Server

    Tarbouriech, Sophie; Gomes da Silva Jr, João Manoel; Queinnec, Isabelle

    2011-01-01

    Gives the reader an in-depth understanding of the phenomena caused by the more-or-less ubiquitous problem of actuator saturation. Proposes methods and algorithms designed to avoid, manage or overcome the effects of actuator saturation. Uses a state-space approach to ensure local and global stability of the systems considered. Compilation of fifteen years' worth of research results.

  5. MOSFET Switching Circuit Protects Shape Memory Alloy Actuators

    Science.gov (United States)

    Gummin, Mark A.

    2011-01-01

    A small-footprint, full surface-mount-component printed circuit board employs MOSFET (metal-oxide-semiconductor field-effect transistor) power switches to switch high currents from any input power supply from 3 to 30 V. High-force shape memory alloy (SMA) actuators generally require high current (up to 9 A at 28 V) to actuate. SMA wires (the driving element of the actuators) can be quickly overheated if power is not removed at the end of stroke, which can damage the wires. The new analog driver prevents overheating of the SMA wires in an actuator by momentarily removing power when the end limit switch is closed, thereby allowing complex control schemes to be adopted without concern for overheating. Either an integral pushbutton or microprocessor-controlled gate or control line inputs switch current to the actuator until the end switch line goes from logic high to logic low state. Power is then momentarily removed (switched off by the MOSFET). The analog driver is suited to use with nearly any SMA actuator.

  6. Ultrathin Alvarez lens system actuated by artificial muscles.

    Science.gov (United States)

    Petsch, S; Grewe, A; Köbele, L; Sinzinger, S; Zappe, H

    2016-04-01

    A key feature of Alvarez lenses is that they may be tuned in focal length using lateral rather than axial translation, thus reducing the overall length of a focus-tunable optical system. Nevertheless the bulk of classical microsystems actuators limits further miniaturization. We present here a new, ultrathin focus-tunable Alvarez lens fabricated using molding techniques and actuated using liquid crystal elastomer (LCE) artificial muscle actuators. The large deformation generated by the LCE actuators permits the integration of the actuators in-plane with the mechanical and optical system and thus reduces the device thickness to only 1.6 mm. Movement of the Alvarez lens pair of 178 μm results in a focal length change of 3.3 mm, based on an initial focal length of 28.4 mm. This design is of considerable interest for realization of ultraflat focus-tunable and zoom systems.

  7. Control of a perturbed under-actuated mechanical system

    KAUST Repository

    Zayane, Chadia; Laleg-Kirati, Taous-Meriem; Chemori, Ahmed

    2015-01-01

    In this work, the trajectory tracking problem for an under-actuated mechanical system in presence of unknown input disturbances is addressed. The studied inertia wheel inverted pendulum falls in the class of non minimum phase systems. The proposed

  8. Design and demonstration of a fish robot actuated by a SMA-driven actuation system

    Science.gov (United States)

    Le, Chan H.; Nguyen, Quang S.; Park, Hoon C.

    2010-04-01

    This paper presents a concept of a fish robot actuated by an SMA-based actuator. The bending-type actuator system is composed of a 0.1mm diameter SMA wire and a 0.5mm thick glass/epoxy strip. The SMA wire is installed to the bent composite strip. The actuator can produce about 200gf of blocking force and 3.5mm displacement at the center of the glass/epoxy strip. The bending motion of the actuator is converted into the tail-beat motion of a fish robot through a linkage system. The fish robot is evaluated by measuring the tail-beat angle, swimming speed and thrust produced by the fish robot. The tail-beat angle is about 20° and the maximum swimming speed is about 1.6cm/s. The measured thrust is about 0.4gf when the fish robot is operated at 0.9Hz.

  9. Reconfigurable Control of Input Affine Nonlinear Systems under Actuator Fault

    DEFF Research Database (Denmark)

    Tabatabaeipour, Mojtaba; Galeazzi, Roberto

    2015-01-01

    loop is preserved. The RB is realized by a virtual actuator and a reference model. Using notions of incremental and input-to-state stability (ISS), it is shown that ISS of the closed-loop reconfigured system can be achieved by the separate design of the virtual actuator. The proposed method does...... not need any knowledge of the nominal controller and only assumes that the nominal closed-loop system is ISS. The method is demonstrated on a dynamic positioning system for an offshore supply vessel, where the virtual actuator is designed using backstepping....

  10. Sensor-actuator system for dynamic chloride ion determination.

    Science.gov (United States)

    de Graaf, Derk Balthazar; Abbas, Yawar; Gerrit Bomer, Johan; Olthuis, Wouter; van den Berg, Albert

    2015-08-12

    Chloride is a crucial anion for various analytical applications from biological to environmental applications. In order to measure the chloride ion concentration, a measurement system is needed which can detect this concentration for prolonged times reliably. Chronopotentiometry is a technique which does not need a long term stable reference electrode and is therefore very suitable for prolonged ion concentration measurements. As the used electrode might be fouled by reaction products, this work focuses on a chronopotentiometric approach with a separated sensing electrode (sensor) and actuating electrode (actuator). Both actuation and sensor electrode are made of Ag/AgCl. A constant current is applied to the actuator and will start the reaction between Ag and Cl-, while the resulting Cl- ion concentration change is observed through the sensor, which is placed close to the actuator. The time it takes to locally deplete the Cl- ions is called transition time. Experiments were performed to verify the feasibility of this approach. The performed experiments show that the sensor detects the local concentration changes resulting from the current applied to the actuator. A linear relation between the Cl- ion concentration and the square root of the transition time was observed, just as was predicted by theory. The calibration curves for different chips showed that both a larger sensor and a larger distance between sensor and actuator resulted in a larger time delay between the transition time detected at the actuator and the sensor. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Hydraulically-actuated operating system for an electric circuit breaker

    Science.gov (United States)

    Barkan, Philip; Imam, Imdad

    1978-01-01

    This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A vent is located hydraulically between the actuating space and the valve for affording communication between said actuating space and a low pressure region. Flow control means is provided for restricting leakage through said vent to a rate that prevents said leakage from substantially detracting from the development of pressure within said actuatng space during the period from initial opening of the valve to the time when said piston has moved through most of its opening stroke. Following such period and while the valve is still open, said flow control means allows effective leakage through said vent. The accumulator has a limited capacity that results in the pressure within said actuating space decaying promptly to a low value as a result of effective leakage through said vent after the piston has moved through a circuit-breaker opening stroke and while the valve is in its open state. Means is provided for resetting the valve to its closed state in response to said pressure decay in the actuating space.

  12. Design, construction and implementation of two redundant circuits of the actuation logic of the protection system of the new control console of TRIGA Mark III reactor of ININ

    International Nuclear Information System (INIS)

    Celestino M, E.

    2016-01-01

    The Instituto Nacional de Investigaciones Nucleares (ININ) in Mexico has a nuclear reactor type TRIGA Mark III, which was put into operation in 1968. The reactor is used for staff training, radioisotope production, and for research projects of different areas. Over time and due to advances constantly has the electronics industry, maintenance of electronic systems is complicated because basically sometimes components that are no longer manufactured or no longer exist in the market, making it necessary to create projects required modernization. This is the case of the TRIGA reactor of ININ, so the Department of Automation and Instrumentation ININ is undertaking a new project to update the reactor control console. Systems that make up a nuclear reactor protection system (Ps) is relevant, since it is responsible for generating the necessary steps to shut down the reactor to an event of uncertainty which could affect the operators or the installation own actions. As part of the renovation project, this study design is presented to update the Logic of Action (La) of the Ps, whose final design must meet the requirements or specifications set by users and or regulations applicable to nuclear research reactors. One of the requirements established for the proposed new design La, is that it must be implemented with components and devices manufactured with latest technologies, and readily available on the market. The design which is operating currently uses TTL logic whose components are no longer available in the market, so for the new design you decide to use programmable circuits, and specifically, the CPLDs called (by the acronym Complex Programmable Logic Device). These CPLDs are electronic devices that solve complex logic equations and meeting the requirements of functionality and modernity for the new design of the La. In this work the criteria used for the selection of the CPLDs considering the availability and ease of software and hardware to use, and the design and

  13. Solar photovoltaic water pumping system using a new linear actuator

    OpenAIRE

    Andrada Gascón, Pedro; Castro, Javier

    2007-01-01

    In this paper a photovoltaic solar pumping system using a new linear actuator is presented. This linear actuator is a double-sided flat two-phase variable-reluctance linear stepper motor that moves a piston-type water pump with the help of a rope, a pulley and a counterweight. The entire actuator pump ensemble is controlled by a simple electronic unit that manages the electric power generated by a photovoltaic array. The proposed system is suitable for rural communities in developing...

  14. Adaptive Non-linear Control of Hydraulic Actuator Systems

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Conrad, Finn

    1998-01-01

    Presentation of two new developed adaptive non-liner controllers for hydraulic actuator systems to give stable operation and improved performance.Results from the IMCIA project supported by the Danish Technical Research Council (STVF).......Presentation of two new developed adaptive non-liner controllers for hydraulic actuator systems to give stable operation and improved performance.Results from the IMCIA project supported by the Danish Technical Research Council (STVF)....

  15. Optimal Sensor and Actuator Location for Unstable Systems

    DEFF Research Database (Denmark)

    Shaker, Hamid Reza; Tahavori, Maryamsadat

    2013-01-01

    on the processes. Dually the problem of placing actuators on the processes is equally important. In this paper, the problem of determining optimal sensor and actuator locations for the linear systems is addressed. The problem of the sensor locations is viewed as the problem of maximizing the output energy...... generated by a given state and for the actuator locations is viewed as the problem of minimizing the input energy required to reach a given state. Such design problems occur in many applications, and therefore have been studied extensively. Unfortunately, the results in this context, which have been...

  16. Stabilization of Neutral Systems with Saturating Actuators

    Directory of Open Access Journals (Sweden)

    F. El Haoussi

    2012-01-01

    to determine stabilizing state-feedback controllers with large domain of attraction, expressed as linear matrix inequalities, readily implementable using available numerical tools and with tuning parameters that make possible to select the most adequate solution. These conditions are derived by using a Lyapunov-Krasovskii functional on the vertices of the polytopic description of the actuator saturations. Numerical examples demonstrate the effectiveness of the proposed technique.

  17. Two-stage actuation system using DC motors and piezoelectric actuators for controllable industrial and automotive brakes and clutches

    Science.gov (United States)

    Neelakantan, Vijay A.; Washington, Gregory N.; Bucknor, Norman K.

    2005-05-01

    High bandwidth actuation systems that are capable of simultaneously producing relatively large forces and displacements are required for use in automobiles and other industrial applications. Conventional hydraulic actuation mechanisms used in automotive brakes and clutches are complex, inefficient and have poor control robustness. These lead to reduced fuel economy, controllability issues and other disadvantages. This paper involves the design, development, testing and control of a two-stage hybrid actuation mechanism by combining classical actuators like DC motors and advanced smart material actuators like piezoelectric actuators. The paper also discusses the development of a robust control methodology using the Internal Model Control (IMC) principle and emphasizes the robustness property of this control methodology by comparing and studying simulation and experimental results.

  18. Reconfigurability of Piecewise Affine Systems Against Actuator Faults

    DEFF Research Database (Denmark)

    Tabatabaeipour, Seyed Mojtaba; Gholami, Mehdi; Bak, Thomas

    2011-01-01

    In this paper, we consider the problem of recongurability of peicewise ane (PWA) systems. Actuator faults are considered. A system subject to a fault is considered as recongurable if it can be stabilized by a state feedback controller and the optimal cost of the performance of the systems...

  19. Design of Transputer Controllers for Hydraulic Actuator Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    1996-01-01

    The paper deals with how transputers can be applied for fast controllers for hydraulic actuator systems. A general transputer-based control systems including a data acquisition transputer subsystem is presented. An application case: development of a mechatronic test facility with a fast hydraulic...... test robot controlled by a transputer-basec controller is presented. Some experimental path-tracking results with adaptive control algorithms are presented and discussed. The results confirm that transputers have significant advantages for intelligent control of actuator systems and robots for high...

  20. Actuator prototype system by voice commands using free software

    Directory of Open Access Journals (Sweden)

    Jaime Andrango

    2016-06-01

    Full Text Available This prototype system is a software application that through the use of techniques of digital signal processing, extracts information from the user's speech, which is then used to manage the on/off actuator on a peripheral computer when vowels are pronounced. The method applies spectral differences. The application uses the parallel port as actuator, with the information recorded in the memory address 378H. This prototype was developed using free software tools for its versatility and dynamism, and to allow other researchers to base on it for further studies.

  1. Floating electrode microelectromechanical system capacitive switches: A different actuation mechanism

    Science.gov (United States)

    Papaioannou, G.; Giacomozzi, F.; Papandreou, E.; Margesin, B.

    2011-08-01

    The paper investigates the actuation mechanism in floating electrode microelectromechanical system capacitive switches. It is demonstrated that in the pull-in state, the device operation turns from voltage to current controlled actuation. The current arises from Poole-Frenkel mechanism in the dielectric film and Fowler-Nordheim in the bridge-floating electrode air gap. The pull-out voltage seems to arise from the abrupt decrease of Fowler-Nordheim electric field intensity. This mechanism seems to be responsible for the very small difference with respect to the pull-in voltage.

  2. Actuator-Assisted Calibration of Freehand 3D Ultrasound System.

    Science.gov (United States)

    Koo, Terry K; Silvia, Nathaniel

    2018-01-01

    Freehand three-dimensional (3D) ultrasound has been used independently of other technologies to analyze complex geometries or registered with other imaging modalities to aid surgical and radiotherapy planning. A fundamental requirement for all freehand 3D ultrasound systems is probe calibration. The purpose of this study was to develop an actuator-assisted approach to facilitate freehand 3D ultrasound calibration using point-based phantoms. We modified the mathematical formulation of the calibration problem to eliminate the need of imaging the point targets at different viewing angles and developed an actuator-assisted approach/setup to facilitate quick and consistent collection of point targets spanning the entire image field of view. The actuator-assisted approach was applied to a commonly used cross wire phantom as well as two custom-made point-based phantoms (original and modified), each containing 7 collinear point targets, and compared the results with the traditional freehand cross wire phantom calibration in terms of calibration reproducibility, point reconstruction precision, point reconstruction accuracy, distance reconstruction accuracy, and data acquisition time. Results demonstrated that the actuator-assisted single cross wire phantom calibration significantly improved the calibration reproducibility and offered similar point reconstruction precision, point reconstruction accuracy, distance reconstruction accuracy, and data acquisition time with respect to the freehand cross wire phantom calibration. On the other hand, the actuator-assisted modified "collinear point target" phantom calibration offered similar precision and accuracy when compared to the freehand cross wire phantom calibration, but it reduced the data acquisition time by 57%. It appears that both actuator-assisted cross wire phantom and modified collinear point target phantom calibration approaches are viable options for freehand 3D ultrasound calibration.

  3. Intelligent fault diagnosis and failure management of flight control actuation systems

    Science.gov (United States)

    Bonnice, William F.; Baker, Walter

    1988-01-01

    The real-time fault diagnosis and failure management (FDFM) of current operational and experimental dual tandem aircraft flight control system actuators was investigated. Dual tandem actuators were studied because of the active FDFM capability required to manage the redundancy of these actuators. The FDFM methods used on current dual tandem actuators were determined by examining six specific actuators. The FDFM capability on these six actuators was also evaluated. One approach for improving the FDFM capability on dual tandem actuators may be through the application of artificial intelligence (AI) technology. Existing AI approaches and applications of FDFM were examined and evaluated. Based on the general survey of AI FDFM approaches, the potential role of AI technology for real-time actuator FDFM was determined. Finally, FDFM and maintainability improvements for dual tandem actuators were recommended.

  4. Piezoelectric Multilayer-Stacked Hybrid Actuation/Transduction System

    Science.gov (United States)

    Xu, Tian-Bing (Inventor); Jiang, Xiaoning (Inventor); Su, Ji (Inventor)

    2014-01-01

    A novel full piezoelectric multilayer stacked hybrid actuation/transduction system. The system demonstrates significantly-enhanced electromechanical performance by utilizing the cooperative contributions of the electromechanical responses of multilayer stacked negative and positive strain components. Both experimental and theoretical studies indicate that for this system, the displacement is over three times that of a same-sized conventional flextensional actuator/transducer. The system consists of at least 2 layers which include electromechanically active components. The layers are arranged such that when electric power is applied, one layer contracts in a transverse direction while the second layer expands in a transverse direction which is perpendicular to the transverse direction of the first layer. An alternate embodiment includes a third layer. In this embodiment, the outer two layers contract in parallel transverse directions while the middle layer expands in a transverse direction which is perpendicular to the transverse direction of the outer layers.

  5. Control of a perturbed under-actuated mechanical system

    KAUST Repository

    Zayane, Chadia

    2015-11-05

    In this work, the trajectory tracking problem for an under-actuated mechanical system in presence of unknown input disturbances is addressed. The studied inertia wheel inverted pendulum falls in the class of non minimum phase systems. The proposed high order sliding mode control architecture including a controller and differentiator allows to track accurately the predefined trajectory and to stabilize the internal dynamics. The robustness of the proposed approach is illustrated through different perturbation and output noise configurations.

  6. Finite Energy and Bounded Actuator Attacks on Cyber-Physical Systems

    Energy Technology Data Exchange (ETDEWEB)

    Djouadi, Seddik M [ORNL; Melin, Alexander M [ORNL; Ferragut, Erik M [ORNL; Laska, Jason A [ORNL; Dong, Jin [ORNL; Drira, Anis [ORNL

    2015-01-01

    As control system networks are being connected to enterprise level networks for remote monitoring, operation, and system-wide performance optimization, these same connections are providing vulnerabilities that can be exploited by malicious actors for attack, financial gain, and theft of intellectual property. Much effort in cyber-physical system (CPS) protection has focused on protecting the borders of the system through traditional information security techniques. Less effort has been applied to the protection of cyber-physical systems from intelligent attacks launched after an attacker has defeated the information security protections to gain access to the control system. In this paper, attacks on actuator signals are analyzed from a system theoretic context. The threat surface is classified into finite energy and bounded attacks. These two broad classes encompass a large range of potential attacks. The effect of theses attacks on a linear quadratic (LQ) control are analyzed, and the optimal actuator attacks for both finite and infinite horizon LQ control are derived, therefore the worst case attack signals are obtained. The closed-loop system under the optimal attack signals is given and a numerical example illustrating the effect of an optimal bounded attack is provided.

  7. Multi-actuators vehicle collision avoidance system - Experimental validation

    Science.gov (United States)

    Hamid, Umar Zakir Abdul; Zakuan, Fakhrul Razi Ahmad; Akmal Zulkepli, Khairul; Zulfaqar Azmi, Muhammad; Zamzuri, Hairi; Rahman, Mohd Azizi Abdul; Aizzat Zakaria, Muhammad

    2018-04-01

    The Insurance Institute for Highway Safety (IIHS) of the United States of America in their reports has mentioned that a significant amount of the road mishaps would be preventable if more automated active safety applications are adopted into the vehicle. This includes the incorporation of collision avoidance system. The autonomous intervention by the active steering and braking systems in the hazardous scenario can aid the driver in mitigating the collisions. In this work, a real-time platform of a multi-actuators vehicle collision avoidance system is developed. It is a continuous research scheme to develop a fully autonomous vehicle in Malaysia. The vehicle is a modular platform which can be utilized for different research purposes and is denominated as Intelligent Drive Project (iDrive). The vehicle collision avoidance proposed design is validated in a controlled environment, where the coupled longitudinal and lateral motion control system is expected to provide desired braking and steering actuation in the occurrence of a frontal static obstacle. Results indicate the ability of the platform to yield multi-actuators collision avoidance navigation in the hazardous scenario, thus avoiding the obstacle. The findings of this work are beneficial for the development of a more complex and nonlinear real-time collision avoidance work in the future.

  8. Pneumatic Muscle Actuated Compliant Gripper Systems

    Directory of Open Access Journals (Sweden)

    Deaconescu Andrea

    2016-01-01

    Full Text Available The paper presents the stages of developing new, light, eco-friendly and bionic gripper systems. Gripping is achieved by means of original, self adaptive, bio-inspired systems, with a pneumatic muscle as motion generator. The method underlying the development of these new gripping systems is based on the creation of concepts by analogy, an instrument aimed at widening the inspiration horizon in designing by using models from nature.

  9. Pneumatic Muscle Actuated Compliant Gripper Systems

    OpenAIRE

    Deaconescu Andrea

    2016-01-01

    The paper presents the stages of developing new, light, eco-friendly and bionic gripper systems. Gripping is achieved by means of original, self adaptive, bio-inspired systems, with a pneumatic muscle as motion generator. The method underlying the development of these new gripping systems is based on the creation of concepts by analogy, an instrument aimed at widening the inspiration horizon in designing by using models from nature.

  10. A review on optical actuators for microfluidic systems

    Science.gov (United States)

    Yang, Tie; Chen, Yue; Minzioni, Paolo

    2017-12-01

    During the last few decades microfluidic systems have become more and more popular and their relevance in different fields is continually growing. In fact, the use of microchannels allows a significant reduction of the required sample-volume and opens the way to a completely new set of possible investigations, including the study of the properties of cells, the development of new cells’ separation techniques and the analysis of single-cell proteins. One of the main differences between microscopic and macroscopic systems is obviously dictated by the need for suitable actuation mechanisms, which should allow precise control of microscopic fluid volumes and of micro-samples inside the fluid. Even if both syringe-pump and pneumatic-pump technologies significantly evolved and they currently enable sub-μL samples control, completely new approaches were recently developed for the manipulation of samples inside the microchannel. This review is dedicated to describing different kinds of optical actuators that can be applied in microfluidic systems for sample manipulation as well as for pumping. The basic principles underlying the optical actuation mechanisms will be described first, and then several experimental demonstrations will be reviewed and compared.

  11. Experimental analysis of chaos in under actuated electromechanical systems

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Hernandez, H. G. [Universidad la Salle, Mexico, D.F. (Mexico); Alvarez Gallegos, Jaime [Instituto Politecnico Nacional (Mexico); Alvarez Gallegos Joaquin [Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, Ensenada, Baja California (Mexico)

    2001-10-01

    An under actuated system is a kind of non-autonomous robotic system in which there are more links than actuators. The complexity of the dynamical behavior of these systems allows a wide variety of steady-state responses. The reconstruction of attractors based on time series obtained from measurements of one of the variables of a two-link, planar, under actuated robot called Pendubot, is developed. Time-delay coordinates, average mutual information, and percentage of false nearest neighbors' methods are used to reconstruct the invariant sets. It is shown that, under the action of a periodic torque, the Pendubot can display a variety of steady-state dynamics, including strange attractors. [Spanish] Un sistema electromecanico subactuado es un tipo de sistema robotico no autonomo que cuenta con mas eslabones que actuadores. La complejidad del comportamiento dinamico de estos sistemas permite una gran variedad de respuestas en estado estacionario. En este trabajo se desarrolla la reconstruccion de atractores basada en series de tiempo obtenidas a partir de mediciones de una de las variables de un robot planar de dos grados de libertad subactuado llamado Pendubot. A fin de reconstruir los conjuntos invariantes, se utilizan tecnica como retraso de coordenadas, promedio de informacion mutua y porcentaje de falsos vecinos cercanos. Se muestra que bajo la accion de un torque periodico, el Pendubot puede desplegar una variedad de comportamientos dinamicos en estado estacionario incluyendo atractores extranos.

  12. Modelling and control of a nonlinear magnetostrictive actuator system

    Science.gov (United States)

    Ramli, M. H. M.; Majeed, A. P. P. Abdul; Anuar, M. A. M.; Mohamed, Z.

    2018-04-01

    This paper explores the implementation of a feedforward control method to a nonlinear control system, in particular, Magnetostrictive Actuators (MA) that has excellent properties of energy conversion between the mechanical and magnetic form through magnetostriction effects which could be used in actuating and sensing application. MA is known to exhibit hysteresis behaviour and it is rate dependent (the level of hysteresis depends closely on the rate of input excitation frequency). This is, nonetheless, an undesirable behaviour and has to be eliminated in realising high precision application. The MA is modelled by a phenomenological modelling approach via Prandtl-Ishlinskii (P-I) operator to characterise the hysteresis nonlinearities. A feedforward control strategy is designed and implemented to linearize and eliminate the hysteresis by model inversion. The results show that the P-I operator has the capability to model the hysteretic nonlinearity of MA with an acceptable accuracy. Furthermore, the proposed control scheme has demonstrated to be effective in providing superior trajectory tracking.

  13. Delayed system control in presence of actuator saturation

    Directory of Open Access Journals (Sweden)

    A. Mahjoub

    2014-09-01

    Full Text Available The paper is introducing a new design method for systems’ controllers with input delay and actuator saturations and focuses on how to force the system output to track a reference input not necessarily saturation-compatible. We propose a new norm based on the way we quantify tracking performance as a function of saturation errors found using the same norm. The newly defined norm is related to signal average power making possible to account for most common reference signals e.g. step, periodic. It is formally shown that, whatever the reference shape and amplitude, the achievable tracking quality is determined by a well defined reference tracking mismatch error. This latter depends on the reference rate and its compatibility with the actuator saturation constraint. In fact, asymptotic output-reference tracking is achieved in the presence of constraint-compatible step-like references.

  14. Power supply for wireless sensor or actuator systems

    International Nuclear Information System (INIS)

    Reindl, L. M.

    2011-01-01

    Portable wireless sensor or actuator systems, like portable phones, remote control, or ID cards play an ever growing role in our industrialized environment. Those systems and many more were enabled due to the steady decreasing power consumption of high integrated ICs. Most such systems are powered by batteries or inductive coupling. In this presentation several concepts for an alternative power supply of wireless sensor or actuator systems are discussed in detail. Batteries, although today mostly used, suffer from a limited storage capacity, which induce a labour and sometimes cost-intensive periodic maintenance, and a problematic ecological impact. The operating range of inductive coupling systems is due to the near ?eld limited to the aperture of the coupling coil. UHF systems operate in the far field and reach higher distances. Their operating range is limited by the distance where the voltage at the feeding point of the antenna becomes too low to drive the rectifier circuit. Larger read out ranges become feasible by omitting the rectifier stage. In this case we need either a passive frequency modulating device to shift the read out signal to a side band, or a resonator with a high quality factor, like a SAW or BAW device, to store the energy until all environmental echoes are feed away. For many applications, both indoor and outdoor, energy harvesting system become feasible which convert ambient power densities like light, RF fields, special or temporal thermal gradients, or mechanical vibrations into electrical supply power of the wireless system. All those systems strongly suffer from a lack of energy. Thus new concepts for low-ering the power consumption of a wireless sensor or actuator system by keeping their features remain extreme important. Herby, a new wake up receiver is presented which operates on a current requirement as low as 3 micro A.

  15. Towards Autonomous Control of Hydraulic Actuator Systems

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Conrad, Finn

    1998-01-01

    Presentation of new developed control algorithms to increase autonomy and intelligence of hydraulic control systems. A refinement of relaytuning method is used to determine the control parameters of a lag/lead controller and a poleplacement controller. Further, a fail-safe function is developed...

  16. High speed hydraulically-actuated operating system for an electric circuit breaker

    Science.gov (United States)

    Iman, Imdad

    1983-06-07

    This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a breaker-opening piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A dashpotting mechanism operating separately from the hydraulic actuating system is provided, thereby reducing flow restriction interference with breaker opening.

  17. Simulation of an actuator & drive of a wire drawing machine's mechatronic system using Matlab/Simulink

    Energy Technology Data Exchange (ETDEWEB)

    Tasevski, Gotse; Petreski, Zlatko; Shishkovski, Dejan [Faculty of Mechanical Engineering, ' Ss. Cyril and Methodius' University, Skopje (Macedonia, The Former Yugoslav Republic of)

    2014-07-01

    Simulation of a mechatronic system actuator, implemented in a wire drawing machine, developed in Matlab/Simulink environment is presented in this paper. AC induction motor with vector control drive is chosen as an actuator. Mathematical model of the actuator is expressed in d-q reference frame rotating at synchronous speed. Diagrams for calculation of the important parameters for the simulation of the actuator were constructed. Simulation results from the model behaviour were discussed in comparison with the specified parameters by the manufacturer of the existing actuator integrated in such mechatronic system. (Author)

  18. 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.

  19. Flight Test Experience With an Electromechanical Actuator on the F-18 Systems Research Aircraft

    Science.gov (United States)

    Jensen, Stephen C.; Jenney, Gavin D.; Raymond, Bruce; Dawson, David

    2000-01-01

    Development of reliable power-by-wire actuation systems for both aeronautical and space applications has been sought recently to eliminate hydraulic systems from aircraft and spacecraft and thus improve safety, efficiency, reliability, and maintainability. The Electrically Powered Actuation Design (EPAD) program was a joint effort between the Air Force, Navy, and NASA to develop and fly a series of actuators validating power-by-wire actuation technology on a primary flight control surface of a tactical aircraft. To achieve this goal, each of the EPAD actuators was installed in place of the standard hydraulic actuator on the left aileron of the NASA F/A-18B Systems Research Aircraft (SRA) and flown throughout the SRA flight envelope. Numerous parameters were recorded, and overall actuator performance was compared with the performance of the standard hydraulic actuator on the opposite wing. This paper discusses the integration and testing of the EPAD electromechanical actuator (EMA) on the SRA. The architecture of the EMA system is discussed, as well as its integration with the F/A-18 Flight Control System. The flight test program is described, and actuator performance is shown to be very close to that of the standard hydraulic actuator it replaced. Lessons learned during this program are presented and discussed, as well as suggestions for future research.

  20. A Systems Engineering Approach to Electro-Mechanical Actuator Diagnostic and Prognostic Development

    Data.gov (United States)

    National Aeronautics and Space Administration — The authors have formulated a Comprehensive Systems Engineering approach to Electro-Mechanical Actuator (EMA) Prognostics and Health Management (PHM) system...

  1. A portable air jet actuator device for mechanical system identification

    Science.gov (United States)

    Belden, Jesse; Staats, Wayne L.; Mazumdar, Anirban; Hunter, Ian W.

    2011-03-01

    System identification of limb mechanics can help diagnose ailments and can aid in the optimization of robotic limb control parameters and designs. An interesting fluid phenomenon—the Coandă effect—is utilized in a portable actuator to provide a stochastic binary force disturbance to a limb system. The design of the actuator is approached with the goal of creating a portable device which could be deployed on human or robotic limbs for in situ mechanical system identification. The viability of the device is demonstrated by identifying the parameters of an underdamped elastic beam system with fixed inertia and stiffness and variable damping. The nonparametric compliance impulse response yielded from the system identification is modeled as a second-order system and the resultant parameters are found to be in excellent agreement with those found using more traditional system identification techniques. The current design could be further miniaturized and developed as a portable, wireless, unrestrained mechanical system identification instrument for less intrusive and more widespread use.

  2. Machine protection systems

    CERN Document Server

    Macpherson, A L

    2010-01-01

    A summary of the Machine Protection System of the LHC is given, with particular attention given to the outstanding issues to be addressed, rather than the successes of the machine protection system from the 2009 run. In particular, the issues of Safe Machine Parameter system, collimation and beam cleaning, the beam dump system and abort gap cleaning, injection and dump protection, and the overall machine protection program for the upcoming run are summarised.

  3. OMS engine shutoff valve and actuation system design and evaluation. [for space shuttles

    Science.gov (United States)

    Wichmann, H.

    1974-01-01

    Shutoff valve and actuation system concepts that are most suitable for the Orbital Maneuvering Systems engine application were determined. Emphasis was placed on the ten year and 100 mission life requirement, propellant and propellant residue compatibility and weight. It was found that poppet or ball valves utilizing electric or electropneumatic actuation were most applicable. Preliminary design layouts of a number of valve and actuation concepts were prepared and analyzed to make the optimum concept selection. Pneumatic actuation systems were required to feature their own pneumatic supply so that for the quad redundant valve, it was necessary to include two pneumatic supply systems, one for each of the series legs of the quad redundant package. The requirement for the pneumatic package placed heavy reliability, weight, and maintenance penalties upon electropneumatic actuation systems. The two valve and actuation systems concepts selected featured electric torque motor operation and a poppet as well as a ball valve concept with a retractable seal.

  4. Development of an air-operated actuator performance monitoring system for regulatory usage

    International Nuclear Information System (INIS)

    Sung, K. Y.; Kwon, S. J.

    2004-01-01

    The performance monitoring system of air-operated actuators for regulatory usage has been being developed. Essential elements and operating parameters affecting the actuator performance have been investigated to provide basic information for system development. The monitoring system including an air-operated actuator testing facility and analysis softwares for monitoring and evaluation are also introduced in this paper. As a result of simulated tests, it was known that the system could be a useful tool for the effective monitoring of actuator performance change and fault conditions. This system would be applied to regulatory inspection for utility's data validation and to the training of regulatory staff in future after some modification and expansion

  5. Modelling of coulometric sensor-actuator systems based on ISFETs with a porous actuator covering the gate

    NARCIS (Netherlands)

    Luo, J.; Luo, J.; Olthuis, Wouter; Bergveld, Piet; Bos, M.; van der Linden, W.E.

    1993-01-01

    The ion-selective field effect transistor (ISFET)-based coulometric sensor¿actuator systems have found applications in acid¿base titration and in the construction of a low-drift carbon dioxide and a pH-static enzyme sensor. In this paper a brief review is given of the previously developed

  6. 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.

  7. Electromagnetic variable degrees of freedom actuator systems and methods

    Science.gov (United States)

    Montesanti, Richard C [Pleasanton, CA; Trumper, David L [Plaistow, NH; Kirtley, Jr., James L.

    2009-02-17

    The present invention provides a variable reluctance actuator system and method that can be adapted for simultaneous rotation and translation of a moving element by applying a normal-direction magnetic flux on the moving element. In a beneficial example arrangement, the moving element includes a swing arm that carries a cutting tool at a set radius from an axis of rotation so as to produce a rotary fast tool servo that provides a tool motion in a direction substantially parallel to the surface-normal of a workpiece at the point of contact between the cutting tool and workpiece. An actuator rotates a swing arm such that a cutting tool moves toward and away from a mounted rotating workpiece in a controlled manner in order to machine the workpiece. Position sensors provide rotation and displacement information for a swing arm to a control system. A control system commands and coordinates motion of the fast tool servo with the motion of a spindle, rotating table, cross-feed slide, and in feed slide of a precision lathe.

  8. Full Piezoelectric Multilayer-Stacked Hybrid Actuation/Transduction Systems

    Science.gov (United States)

    Su, Ji; Jiang, Xiaoning; Zu, Tian-Bing

    2011-01-01

    The Stacked HYBATS (Hybrid Actuation/Transduction system) demonstrates significantly enhanced electromechanical performance by using the cooperative contributions of the electromechanical responses of multilayer, stacked negative strain components and positive strain components. Both experimental and theoretical studies indicate that, for Stacked HYBATS, the displacement is over three times that of a same-sized conventional flextensional actuator/transducer. The coupled resonance mode between positive strain and negative strain components of Stacked HYBATS is much stronger than the resonance of a single element actuation only when the effective lengths of the two kinds of elements match each other. Compared with the previously invented hybrid actuation system (HYBAS), the multilayer Stacked HYBATS can be designed to provide high mechanical load capability, low voltage driving, and a highly effective piezoelectric constant. The negative strain component will contract, and the positive strain component will expand in the length directions when an electric field is applied on the device. The interaction between the two elements makes an enhanced motion along the Z direction for Stacked-HYBATS. In order to dominate the dynamic length of Stacked-HYBATS by the negative strain component, the area of the cross-section for the negative strain component will be much larger than the total cross-section areas of the two positive strain components. The transverse strain is negative and longitudinal strain positive in inorganic materials, such as ceramics/single crystals. Different piezoelectric multilayer stack configurations can make a piezoelectric ceramic/single-crystal multilayer stack exhibit negative strain or positive strain at a certain direction without increasing the applied voltage. The difference of this innovation from the HYBAS is that all the elements can be made from one-of-a-kind materials. Stacked HYBATS can provide an extremely effective piezoelectric

  9. Streaming and particle motion in acoustically-actuated leaky systems

    Science.gov (United States)

    Nama, Nitesh; Barnkob, Rune; Jun Huang, Tony; Kahler, Christian; Costanzo, Francesco

    2017-11-01

    The integration of acoustics with microfluidics has shown great promise for applications within biology, chemistry, and medicine. A commonly employed system to achieve this integration consists of a fluid-filled, polymer-walled microchannel that is acoustically actuated via standing surface acoustic waves. However, despite significant experimental advancements, the precise physical understanding of such systems remains a work in progress. In this work, we investigate the nature of acoustic fields that are setup inside the microchannel as well as the fundamental driving mechanism governing the fluid and particle motion in these systems. We provide an experimental benchmark using state-of-art 3D measurements of fluid and particle motion and present a Lagrangian velocity based temporal multiscale numerical framework to explain the experimental observations. Following verification and validation, we employ our numerical model to reveal the presence of a pseudo-standing acoustic wave that drives the acoustic streaming and particle motion in these systems.

  10. Redundant actuator development study. [flight control systems for supersonic transport aircraft

    Science.gov (United States)

    Ryder, D. R.

    1973-01-01

    Current and past supersonic transport configurations are reviewed to assess redundancy requirements for future airplane control systems. Secondary actuators used in stability augmentation systems will probably be the most critical actuator application and require the highest level of redundancy. Two methods of actuator redundancy mechanization have been recommended for further study. Math models of the recommended systems have been developed for use in future computer simulations. A long range plan has been formulated for actuator hardware development and testing in conjunction with the NASA Flight Simulator for Advanced Aircraft.

  11. Double-Acting Sleeve Muscle Actuator for Bio-Robotic Systems

    Directory of Open Access Journals (Sweden)

    Hao Zheng

    2013-11-01

    Full Text Available This paper presents a new type of muscle-like actuator, namely double-acting (DA sleeve muscle actuator, which is suitable for the actuation of biologically-inspired and biomedical robotic systems, especially those serving human-assistance purposes (prostheses, orthoses, etc.. Developed based on the traditional pneumatic muscle actuator, the new DA sleeve muscle incorporates a unique insert at the center. With the insert occupying the central portion of the internal volume, this new actuator enjoys multiple advantages relative to the traditional pneumatic muscle, including a consistent increase of force capacity over the entire range of motion, and a significant decrease of energy consumption in operation. Furthermore, the insert encompasses an additional chamber, which generates an extension force when pressurized. As such, this new actuator provides a unique bi-directional actuation capability, and, thus, has a potential to significantly simplify the design of a muscle actuator-powered robotic system. To demonstrate this new actuator concept, a prototype has been designed and fabricated, and experiments conducted on this prototype demonstrated the enhanced force capacity and the unique bi-directional actuation capability.

  12. Double-Acting Sleeve Muscle Actuator for Bio-Robotic Systems

    Science.gov (United States)

    Zheng, Hao; Shen, Xiangrong

    2014-01-01

    This paper presents a new type of muscle-like actuator, namely double-acting (DA) sleeve muscle actuator, which is suitable for the actuation of biologically-inspired and biomedical robotic systems, especially those serving human-assistance purposes (prostheses, orthoses, etc.). Developed based on the traditional pneumatic muscle actuator, the new DA sleeve muscle incorporates a unique insert at the center. With the insert occupying the central portion of the internal volume, this new actuator enjoys multiple advantages relative to the traditional pneumatic muscle, including a consistent increase of force capacity over the entire range of motion, and a significant decrease of energy consumption in operation. Furthermore, the insert encompasses an additional chamber, which generates an extension force when pressurized. As such, this new actuator provides a unique bi-directional actuation capability, and, thus, has a potential to significantly simplify the design of a muscle actuator-powered robotic system. To demonstrate this new actuator concept, a prototype has been designed and fabricated, and experiments conducted on this prototype demonstrated the enhanced force capacity and the unique bi-directional actuation capability. PMID:25264492

  13. Double-Acting Sleeve Muscle Actuator for Bio-Robotic Systems.

    Science.gov (United States)

    Zheng, Hao; Shen, Xiangrong

    2013-11-25

    This paper presents a new type of muscle-like actuator, namely double-acting (DA) sleeve muscle actuator, which is suitable for the actuation of biologically-inspired and biomedical robotic systems, especially those serving human-assistance purposes (prostheses, orthoses, etc .). Developed based on the traditional pneumatic muscle actuator, the new DA sleeve muscle incorporates a unique insert at the center. With the insert occupying the central portion of the internal volume, this new actuator enjoys multiple advantages relative to the traditional pneumatic muscle, including a consistent increase of force capacity over the entire range of motion, and a significant decrease of energy consumption in operation. Furthermore, the insert encompasses an additional chamber, which generates an extension force when pressurized. As such, this new actuator provides a unique bi-directional actuation capability, and, thus, has a potential to significantly simplify the design of a muscle actuator-powered robotic system. To demonstrate this new actuator concept, a prototype has been designed and fabricated, and experiments conducted on this prototype demonstrated the enhanced force capacity and the unique bi-directional actuation capability.

  14. Iridium oxide as actuator material for the ISFET-based sensor-actuator system

    NARCIS (Netherlands)

    Olthuis, Wouter; Bomer, Johan G.; Bergveld, Piet; van der Linden, W.E.; Bos, M.; Bos, M.

    1991-01-01

    Acid or base concentrations can be determined by performing an acid-base titration with Coulometrically generated OH- or H+ ions at a noble-metal actuator electrode in close proximity to the pH-sensitive gate of an ISFET. The ISFET is used as the indicator electrode to detect the equivalence point

  15. Active-passive hybrid piezoelectric actuators for high-precision hard disk drive servo systems

    Science.gov (United States)

    Chan, Kwong Wah; Liao, Wei-Hsin

    2006-03-01

    Positioning precision is crucial to today's increasingly high-speed, high-capacity, high data density, and miniaturized hard disk drives (HDDs). The demand for higher bandwidth servo systems that can quickly and precisely position the read/write head on a high track density becomes more pressing. Recently, the idea of applying dual-stage actuators to track servo systems has been studied. The push-pull piezoelectric actuated devices have been developed as micro actuators for fine and fast positioning, while the voice coil motor functions as a large but coarse seeking. However, the current dual-stage actuator design uses piezoelectric patches only without passive damping. In this paper, we propose a dual-stage servo system using enhanced active-passive hybrid piezoelectric actuators. The proposed actuators will improve the existing dual-stage actuators for higher precision and shock resistance, due to the incorporation of passive damping in the design. We aim to develop this hybrid servo system not only to increase speed of track seeking but also to improve precision of track following servos in HDDs. New piezoelectrically actuated suspensions with passive damping have been designed and fabricated. In order to evaluate positioning and track following performances for the dual-stage track servo systems, experimental efforts are carried out to implement the synthesized active-passive suspension structure with enhanced piezoelectric actuators using a composite nonlinear feedback controller.

  16. IVVS actuating system compatibility test to ITER gamma radiation conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, Paolo, E-mail: paolo.rossi@enea.it [Associazione EURATOM-ENEA sulla Fusione, 45 Via Enrico Fermi, 00044 Frascati, Rome (Italy); Collibus, M. Ferri de; Florean, M.; Monti, C.; Mugnaini, G.; Neri, C.; Pillon, M.; Pollastrone, F. [Associazione EURATOM-ENEA sulla Fusione, 45 Via Enrico Fermi, 00044 Frascati, Rome (Italy); Baccaro, S.; Piegari, A. [ENEA CR Casaccia, 301 Via Anguillarese, 00123 Santa Maria di Galeria, Rome (Italy); Damiani, C.; Dubus, G. [Fusion For Energy c/Josep Pla, n° 2 Torres Diagonal Litoral, 08019 Barcelona (Spain)

    2013-10-15

    Highlights: • ENEA developed and tested a prototype of a laser In Vessel Viewing and ranging System (IVVS) for ITER. • One piezo-motor prototype has been tested on the ENEA Calliope gamma irradiation facility to verify its compatibility to ITER gamma radiation conditions. • After a total dose of more than 4 MGy the piezo-motor maintained almost the same working parameters monitored before test without any evident and significant degradation of functionality. • After the full gamma irradiation test, the same piezo-motor assembly will be tested with 14 MeV neutrons irradiation using ENEA FNG facility. -- Abstract: The In Vessel Viewing System (IVVS) is a fundamental remote handling equipment, which will be used to make a survey of the status of the blanket first wall and divertor plasma facing components. A design and testing activity is ongoing, in the framework of a Fusion for Energy (F4E) grant agreement, to make the IVVS probe design compatible with ITER operating conditions and in particular, but not only, with attention to neutrons and gammas fluxes and both space constraints and interfaces. The paper describes the testing activity performed on the customized piezoelectric motors and the main components of the actuating system of the IVVS probe with reference to ITER gamma radiation conditions. In particular the test is performed on the piezoelectric motor, optical encoder and small scale optical samples .The test is carried out on the ENEA Calliope gamma irradiation facility at ITER relevant gamma fields at rate of about 2.5 kGy/h and doses of 4 MGy. The paper reports in detail the setup arrangement of the test campaign in order to verify significant working capability of the IVVS actuating components and the results are shown in terms of functional performances and parameters. The overall test campaign on IVVS actuating system will be completed on other ENEA testing facilities in order to verify compatibility to Magnetic field, neutrons and thermal

  17. IVVS actuating system compatibility test to ITER gamma radiation conditions

    International Nuclear Information System (INIS)

    Rossi, Paolo; Collibus, M. Ferri de; Florean, M.; Monti, C.; Mugnaini, G.; Neri, C.; Pillon, M.; Pollastrone, F.; Baccaro, S.; Piegari, A.; Damiani, C.; Dubus, G.

    2013-01-01

    Highlights: • ENEA developed and tested a prototype of a laser In Vessel Viewing and ranging System (IVVS) for ITER. • One piezo-motor prototype has been tested on the ENEA Calliope gamma irradiation facility to verify its compatibility to ITER gamma radiation conditions. • After a total dose of more than 4 MGy the piezo-motor maintained almost the same working parameters monitored before test without any evident and significant degradation of functionality. • After the full gamma irradiation test, the same piezo-motor assembly will be tested with 14 MeV neutrons irradiation using ENEA FNG facility. -- Abstract: The In Vessel Viewing System (IVVS) is a fundamental remote handling equipment, which will be used to make a survey of the status of the blanket first wall and divertor plasma facing components. A design and testing activity is ongoing, in the framework of a Fusion for Energy (F4E) grant agreement, to make the IVVS probe design compatible with ITER operating conditions and in particular, but not only, with attention to neutrons and gammas fluxes and both space constraints and interfaces. The paper describes the testing activity performed on the customized piezoelectric motors and the main components of the actuating system of the IVVS probe with reference to ITER gamma radiation conditions. In particular the test is performed on the piezoelectric motor, optical encoder and small scale optical samples .The test is carried out on the ENEA Calliope gamma irradiation facility at ITER relevant gamma fields at rate of about 2.5 kGy/h and doses of 4 MGy. The paper reports in detail the setup arrangement of the test campaign in order to verify significant working capability of the IVVS actuating components and the results are shown in terms of functional performances and parameters. The overall test campaign on IVVS actuating system will be completed on other ENEA testing facilities in order to verify compatibility to Magnetic field, neutrons and thermal

  18. Actuation and system design and evaluation OMS engine shutoff valve, Volume 1. [space shuttles

    Science.gov (United States)

    Dunn, V. B.

    1975-01-01

    A technology program was conducted to identify and verify the optimum valve and actuation system concept for the Space Shuttle Orbit Maneuvering System engine. Of major importance to the valve and actuation system selection was the ten-year, 100-mission, 10,000-cycle life requirement, while maintaining high reliability, low leakage, and low weight. Valve and actuation system concepts were comparatively evaluated against past valve failure reports and potential failure modes due to the shuttle mission profile to aid in the selection of the most optimum concept for design, manufacture and verification testing. Two valve concepts were considered during the preliminary design stage; i.e., the moving seat and lifting ball. Two actuation systems were manufactured and tested. Test results demonstrate the viability of a lifting ball concept as well as the applicability of an ac motor actuation system to best meet the requirements of the shuttle mission.

  19. Distributed sensor and actuator reconfiguration for fault-tolerant networked control systems

    NARCIS (Netherlands)

    Herdeiro Teixeira, A.M.; Araujo, Jose; Sandberg, Henrik; Johansson, Karl H.

    2017-01-01

    In this paper, we address the problem of distributed reconfiguration of networked control systems upon the removal of misbehaving sensors and actuators. In particular, we consider systems with redundant sensors and actuators cooperating to recover from faults. Reconfiguration is performed while

  20. Piezoelectric-hydraulic pump based band brake actuation system for automotive transmission control

    Science.gov (United States)

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

    2007-04-01

    The actuation system of friction elements (such as band brakes) is essential for high quality operations in modern automotive automatic transmissions (in short, ATs). The current band brake actuation system consists of several hydraulic components, including the oil pump, the regulating valve and the control valves. In general, it has been recognized that the current AT band brake actuation system has many limitations. For example, the oil pump and valve body are relatively heavy and complex. Also, the oil pumps induce inherently large drag torque, which affects fuel economy. This research is to overcome these problems of the current system by exploring the utilization of a hybrid type piezo-hydraulic pump device for AT band brake control. This new actuating system integrates a piezo-hydraulic pump to the input of the band brake. Compared with the current systems, this new actuator features much simpler structure, smaller size, and lower weight. This paper describes the development, design and fabrication of the new stand-alone prototype actuator for AT band brake control. An analytical model is developed and validated using experimental data. Performance tests on the hardware and system simulations utilizing the validated model are performed to characterize the new prototype actuator. It is predicted that with increasing of accumulator pressure and driving frequency, the proposed prototype actuating system will satisfy the band brake requirement for AT shift control.

  1. Wide-bandwidth bilateral control using two-stage actuator system

    International Nuclear Information System (INIS)

    Kokuryu, Saori; Izutsu, Masaki; Kamamichi, Norihiro; Ishikawa, Jun

    2015-01-01

    This paper proposes a two-stage actuator system that consists of a coarse actuator driven by a ball screw with an AC motor (the first stage) and a fine actuator driven by a voice coil motor (the second stage). The proposed two-stage actuator system is applied to make a wide-bandwidth bilateral control system without needing expensive high-performance actuators. In the proposed system, the first stage has a wide moving range with a narrow control bandwidth, and the second stage has a narrow moving range with a wide control bandwidth. By consolidating these two inexpensive actuators with different control bandwidths in a complementary manner, a wide bandwidth bilateral control system can be constructed based on a mechanical impedance control. To show the validity of the proposed method, a prototype of the two-stage actuator system has been developed and basic performance was evaluated by experiment. The experimental results showed that a light mechanical impedance with a mass of 10 g and a damping coefficient of 2.5 N/(m/s) that is an important factor to establish good transparency in bilateral control has been successfully achieved and also showed that a better force and position responses between a master and slave is achieved by using the proposed two-stage actuator system compared with a narrow bandwidth case using a single ball screw system. (author)

  2. Transducer-actuator systems and methods for performing on-machine measurements and automatic part alignment

    Science.gov (United States)

    Barkman, William E.; Dow, Thomas A.; Garrard, Kenneth P.; Marston, Zachary

    2016-07-12

    Systems and methods for performing on-machine measurements and automatic part alignment, including: a measurement component operable for determining the position of a part on a machine; and an actuation component operable for adjusting the position of the part by contacting the part with a predetermined force responsive to the determined position of the part. The measurement component consists of a transducer. The actuation component consists of a linear actuator. Optionally, the measurement component and the actuation component consist of a single linear actuator operable for contacting the part with a first lighter force for determining the position of the part and with a second harder force for adjusting the position of the part. The actuation component is utilized in a substantially horizontal configuration and the effects of gravitational drop of the part are accounted for in the force applied and the timing of the contact.

  3. Control system design for nano-positioning using piezoelectric actuators

    International Nuclear Information System (INIS)

    Shan, Jinjun; Liu, Yanfang; Cui, Naigang; Gabbert, Ulrich

    2016-01-01

    This paper presents a systematic control system design for nano-positioning of a piezoelectric actuator (PEA). PEAs exhibit hysteresis nonlinearity, which can dramatically limit the application and performance of linear feedback control theory. Thus the hysteresis is compensated for based on the Maxwell resistive capacitor (MRC) model first. Then a proportional plus integral (PI) controller and a proportional double integral plus lead compensation (PII and L) controller are designed for the hysteresis-compensated PEA to account for model uncertainty, disturbance, and noise. The robust stability of both controllers is proved. The effectiveness of the proposed control scheme is demonstrated experimentally. Both controllers achieve fast precise positioning. The 2% settling times for the PI controller and the PII and L controller are 1.5 ms and 4.7 ms, respectively. The positioning resolution is upto 1 nm for both controllers. (paper)

  4. Shape memory system with integrated actuation using embedded particles

    Science.gov (United States)

    Buckley, Patrick R [New York, NY; Maitland, Duncan J [Pleasant Hill, CA

    2009-09-22

    A shape memory material with integrated actuation using embedded particles. One embodiment provides a shape memory material apparatus comprising a shape memory material body and magnetic pieces in the shape memory material body. Another embodiment provides a method of actuating a device to perform an activity on a subject comprising the steps of positioning a shape memory material body in a desired position with regard to the subject, the shape memory material body capable of being formed in a specific primary shape, reformed into a secondary stable shape, and controllably actuated to recover the specific primary shape; including pieces in the shape memory material body; and actuating the shape memory material body using the pieces causing the shape memory material body to be controllably actuated to recover the specific primary shape and perform the activity on the subject.

  5. Investigation and Development of the Thermal Preparation System of the Trailbuilder Machinery Hydraulic Actuator

    Science.gov (United States)

    Konev, V.; Polovnikov, E.; Krut, O.; Merdanov, Sh; Zakirzakov, G.

    2017-07-01

    It’s determined that the main part of trailbuilders operated in the North is the technology equipped by the hydraulic actuator. Further development of the northern territories will demand using of various means and ways machinery thermal preparation, and also the machinery of the northern fulfillment. On this basis problems in equipment operation are defined. One of the main is efficiency supplying of a hydraulic actuator. On the basis of the operating conditions’ analysis of trailbuilder hydraulic actuator operation it is determined, that under low negative temperatures the means of thermal preparation are necessary. The existing systems warm up only a hydraulic tank or warming up of the hydro equipment before the machinery operation is carried out under loading with intensive wears. Thus, with the purpose to raise the efficiency of thermal hydraulic actuator, operated far from stationary bases autonomous, energy saving, not expensive in creation and operation systems are necessary. In accordance with the analysis of means and ways of the thermal preparation of the hydraulic actuator and the thermal balance calculations of the (internal) combustion engine the system of the hydraulic actuator heating is offered and is being investigated. It contains a local hydraulic actuator warming up and the system of internal combustion engine heat utilization. Within research operation conditions of the local hydraulic actuator heating are viewed and determined, taking into account constructive changes to the local hydraulic actuator heating. Mathematical modelling of the heat technical process in the modernized hydraulic actuator is considered. As a result temperature changes of the heat-transfer and the hydraulic cylinder in time are determined. To check the theoretical researches and to define dependences on hydraulic actuator warming up, the experimental installation is made. It contains the measuring equipment, a small tank with the heat exchanger of the burnt gases

  6. Passive Fault-tolerant Control of Discrete-time Piecewise Affine Systems against Actuator Faults

    DEFF Research Database (Denmark)

    Tabatabaeipour, Seyed Mojtaba; Izadi-Zamanabadi, Roozbeh; Bak, Thomas

    2012-01-01

    In this paper, we propose a new method for passive fault-tolerant control of discrete time piecewise affine systems. Actuator faults are considered. A reliable piecewise linear quadratic regulator (LQR) state feedback is designed such that it can tolerate actuator faults. A sufficient condition f...... is illustrated on a numerical example and a two degree of freedom helicopter....

  7. Distributed illumination control with local sensing and actuation in networked lighting systems

    NARCIS (Netherlands)

    Caicedo Fernandez, D.R.; Pandharipande, A.

    2013-01-01

    We consider the problem of illumination control in a networked lighting system wherein luminaires have local sensing and actuation capabilities. Each luminaire (i) consists of a light emitting diode (LED) based light source dimmable by a local controller, (ii) is actuated based on sensing

  8. Fuzzy Adaptive Compensation Control of Uncertain Stochastic Nonlinear Systems With Actuator Failures and Input Hysteresis.

    Science.gov (United States)

    Wang, Jianhui; Liu, Zhi; Chen, C L Philip; Zhang, Yun

    2017-10-12

    Hysteresis exists ubiquitously in physical actuators. Besides, actuator failures/faults may also occur in practice. Both effects would deteriorate the transient tracking performance, and even trigger instability. In this paper, we consider the problem of compensating for actuator failures and input hysteresis by proposing a fuzzy control scheme for stochastic nonlinear systems. Compared with the existing research on stochastic nonlinear uncertain systems, it is found that how to guarantee a prescribed transient tracking performance when taking into account actuator failures and hysteresis simultaneously also remains to be answered. Our proposed control scheme is designed on the basis of the fuzzy logic system and backstepping techniques for this purpose. It is proven that all the signals remain bounded and the tracking error is ensured to be within a preestablished bound with the failures of hysteretic actuator. Finally, simulations are provided to illustrate the effectiveness of the obtained theoretical results.

  9. A modeling framework for deteriorating control system and predictive maintenance of actuators

    International Nuclear Information System (INIS)

    Langeron, Y.; Grall, A.; Barros, A.

    2015-01-01

    Actuators play a central role in industrial automation systems. They are costly, and therefore studying their dependability needs all attention. Usually, an actuator is inserted in a feedback control system, and its mission is to implement a control action delivered by a controller. In this paper, a monotonic actuator deterioration is considered and it is assumed that a relationship exists between the control action and the physical actuator's deterioration. A modeling framework is proposed including a non-decreasing stochastic degradation process driving the inability for an actuator to fully implement its role. The prognosis of the actuator's residual useful lifetime is derived and used to update the controller's setting. The controller reconfiguration completes the maintenance corrective and preventive actions. This new action is suggested as an alternative for maintenance strategy. - Highlights: • A degrading control system model is proposed focusing on actuator deterioration. • It is assumed a relationship between this degradation and its loss of efficiency. • The actuator RUL is quantified as a quantile of its conditional survival function. • RUL prognosis is used to reconfigure the control input law. • This new action is suggested as an alternative for maintenance strategy

  10. Smart cathodic protection systems

    NARCIS (Netherlands)

    Polder, R.B.; Leggedoor, J.; Schuten, G.; Sajna, S.; Kranjc, A.

    2010-01-01

    Cathodic protection delivers corrosion protection in concrete structures exposed to aggressive environments, e.g. in de-icing salt and marine climates. Working lives of a large number of CP systems are at least more than 13 years and probably more than 25 years, provided a minimum level of

  11. Buffer moisture protection system

    International Nuclear Information System (INIS)

    Ritola, J.; Peura, J.

    2013-11-01

    With the present knowledge, bentonite blocks have to be protected from the air relative humidity and from any moisture leakages in the environment that might cause swelling of the bentonite blocks during the 'open' installation phase before backfilling. The purpose of this work was to design the structural reference solution both for the bottom of the deposition hole and for the buffer moisture protection and dewatering system with their integrated equipment needed in the deposition hole. This report describes the Posiva's reference solution for the buffer moisture protection system and the bottom plate on basis of the demands and functional requirements set by long-term safety. The reference solution with structural details has been developed in research work made 2010-2011. The structural solution of the moisture protection system has not yet been tested in practice. On the bottom of the deposition hole a copper plate which protects the lowest bentonite block from the gathered water is installed straight to machined and even rock surface. The moisture protection sheet made of EPDM rubber is attached to the copper plate with an inflatable seal. The upper part of the moisture protection sheet is fixed to the collar structures of the lid which protects the deposition hole in the disposal tunnel. The main function of the moisture protection sheet is to protect bentonite blocks from the leaking water and from the influence of the air humidity at their installation stage. The leaking water is controlled by the dewatering and alarm system which has been integrated into the moisture protection liner. (orig.)

  12. System level ESD protection

    CERN Document Server

    Vashchenko, Vladislav

    2014-01-01

    This book addresses key aspects of analog integrated circuits and systems design related to system level electrostatic discharge (ESD) protection.  It is an invaluable reference for anyone developing systems-on-chip (SoC) and systems-on-package (SoP), integrated with system-level ESD protection. The book focuses on both the design of semiconductor integrated circuit (IC) components with embedded, on-chip system level protection and IC-system co-design. The readers will be enabled to bring the system level ESD protection solutions to the level of integrated circuits, thereby reducing or completely eliminating the need for additional, discrete components on the printed circuit board (PCB) and meeting system-level ESD requirements. The authors take a systematic approach, based on IC-system ESD protection co-design. A detailed description of the available IC-level ESD testing methods is provided, together with a discussion of the correlation between IC-level and system-level ESD testing methods. The IC-level ESD...

  13. Design and performance analysis of position-based impedance control for an electrohydrostatic actuation system

    Directory of Open Access Journals (Sweden)

    Yongling FU

    2018-03-01

    Full Text Available Electrohydrostatic actuator (EHA is a type of power-by-wire actuator that is widely implemented in the aerospace industry for flight control, landing gears, thrust reversers, thrust vector control, and space robots. This paper presents the development and evaluation of position-based impedance control (PBIC for an EHA. Impedance control provides the actuator with compliance and facilitates the interaction with the environment. Most impedance control applications utilize electrical or valve-controlled hydraulic actuators, whereas this work realizes impedance control via a compact and efficient EHA. The structures of the EHA and PBIC are firstly introduced. A mathematical model of the actuation system is established, and values of its coefficients are identified by particle swarm optimization. This model facilitates the development of a position controller and the selection of target impedance parameters. A nonlinear proportional-integral position controller is developed for the EHA to achieve the accurate positioning requirement of PBIC. The controller compensates for the adverse effect of stiction, and a position accuracy of 0.08 mm is attained. Various experimental results are presented to verify the applicability of PBIC to the EHA. The compliance of the actuator is demonstrated in an impact test. Keywords: Actuation system, Aerospace, Electrohydrostatic actuator, Force control, Nonlinear dynamics, Particle swarm optimization, Position control

  14. Bioinspired Soft Actuation System Using Shape Memory Alloys

    OpenAIRE

    Cianchetti, Matteo; Licofonte, Alessia; Follador, Maurizio; Rogai, Francesco; Laschi, Cecilia

    2014-01-01

    Soft robotics requires technologies that are capable of generating forces even though the bodies are composed of very light, flexible and soft elements. A soft actuation mechanism was developed in this work, taking inspiration from the arm of the Octopus vulgaris, specifically from the muscular hydrostat which represents its constitutive muscular structure. On the basis of the authors’ previous works on shape memory alloy (SMA) springs used as soft actuators, a specific arrangement of such SM...

  15. Parametric model of servo-hydraulic actuator coupled with a nonlinear system: Experimental validation

    Science.gov (United States)

    Maghareh, Amin; Silva, Christian E.; Dyke, Shirley J.

    2018-05-01

    Hydraulic actuators play a key role in experimental structural dynamics. In a previous study, a physics-based model for a servo-hydraulic actuator coupled with a nonlinear physical system was developed. Later, this dynamical model was transformed into controllable canonical form for position tracking control purposes. For this study, a nonlinear device is designed and fabricated to exhibit various nonlinear force-displacement profiles depending on the initial condition and the type of materials used as replaceable coupons. Using this nonlinear system, the controllable canonical dynamical model is experimentally validated for a servo-hydraulic actuator coupled with a nonlinear physical system.

  16. Hybrid microcircuit metallization system for the SLL micro actuator

    International Nuclear Information System (INIS)

    Hampy, R.E.; Knauss, G.L.; Komarek, E.E.; Kramer, D.K.; Villaueva, J.

    1976-03-01

    A thin film technique developed for the SLL Micro Actuator in which both gold and aluminum can be incorporated on sapphire or fine grained alumina substrates in a two-level metallization system is described. Tungsten is used as a lateral transition metal permitting electrical contact between the gold and aluminum without the two metals coming in physical contact. Silicon dioxide serves as an insulator between the tungsten and aluminum for crossover purposes, and vias through the silicon dioxide permit interconnections where desired. Tungsten-gold is the first level conductor except at crossovers where tungsten only is used and aluminum is the second level conductor. Sheet resistances of the two levels can be as low as 0.01 ohm/square. Line widths and spaces as small as 0.025 mm can be attained. A second layer of silicon dioxide is deposited over the metallization and opened for all gold and aluminum bonding areas. The metallization system permits effective interconnection of a mixture of devices having both gold and aluminum terminations without creating undesirable gold-aluminum interfaces. Processing temperatures up to 400 0 C can be tolerated for short times without effect on bondability, conductor, and insulator characteristics, thus permitting silicon-gold eutectic die attachment, component soldering, and higher temperatures during gold lead bonding. Tests conducted on special test pattern circuits indicate good stability over the temperature range -55 to +150 0 C. Aging studies indicate no degradation in characteristics in tests of 500 h duration at 150 0 C

  17. Power system protection

    International Nuclear Information System (INIS)

    Venkata, S.S.; Damborg, M.J.; Jampala, A.K.

    1991-01-01

    Power systems of the 21st century will be more modern, and complex, utilizing the latest available technologies. At the same time, generating plants will have to operate with minimal spinning margins and energy transportation has to take place at critical levels due to environmental and economical constraints. These factors dictate that the power systems be protected with optimum sensitivity, selectivity and time of operation to assure maximum reliability, and security at minimal cost. With an increasing role played by digital computers in every aspect of protection, it is important to take a critical and fresh look at the art and science of relaying and protection. The main objective of this paper is to review the past, present and future of power system protection from a software point of view

  18. Depth protection system

    International Nuclear Information System (INIS)

    Arita, Setsuo; Izumi, Shigeru; Suzuki, Satoru; Noguchi, Atomi.

    1988-01-01

    Purpose: To previously set a nuclear reactor toward safety side by the reactor scram if an emergency core cooling system is failed to operate. Constitution If abnormality occurs in an emergency core cooling system or an aqueous boric acid injection system, a reactor protection system is operated and, if the reactor protection system shows an abnormal state, a control rod withdrawal inhibition system is operated as a fundamental way. For instance, when the driving power source voltage for the emergency core cooling system is detected and, if it is lower than a predetermined value, the reactor protection system is operated. Alternatively, if the voltage goes lower than the predetermined value, the control rod withdrawal is inhibited. In addition, stopping for the feedwater system is inhibited. Further, integrity of the driving means for the emergency core cooling system is positively checked and the protection function is operated depending on the result of check. Since the nuclear reactor can be set toward the safety side even if the voltage for the driving power source of the aqueous boric acid injection system is lower than a predetermined value, the reactor safety can further be improved. (Horiuchi, T.)

  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. Advanced Worker Protection System

    International Nuclear Information System (INIS)

    1996-04-01

    The Advanced Worker Protection System (AWPS) is a liquid-air-based, self-contained breathing and cooling system with a duration of 2 hrs. AWPS employs a patented system developed by Oceaneering Space Systems (OSS), and was demonstrated at their facility in Houston, TX as well as at Kansas State University, Manhattan. The heart of the system is the life-support backpack that uses liquid air to provide cooling as well as breathing gas to the worker. The backpack is combined with advanced protective garments, an advanced liquid cooling garment (LCG), a respirator, and communications and support equipment. The prototype unit development and testing under Phase 1 has demonstrated that AWPS has the ability to meet performance criteria. These criteria were developed with an understanding of both the AWPS capabilities and the DOE decontamination and decommissioning (D and D) activities protection needs

  1. a New ER Fluid Based Haptic Actuator System for Virtual Reality

    Science.gov (United States)

    Böse, H.; Baumann, M.; Monkman, G. J.; Egersdörfer, S.; Tunayar, A.; Freimuth, H.; Ermert, H.; Khaled, W.

    The concept and some steps in the development of a new actuator system which enables the haptic perception of mechanically inhomogeneous virtual objects are introduced. The system consists of a two-dimensional planar array of actuator elements containing an electrorheological (ER) fluid. When a user presses his fingers onto the surface of the actuator array, he perceives locally variable resistance forces generated by vertical pistons which slide in the ER fluid through the gaps between electrode pairs. The voltage in each actuator element can be individually controlled by a novel sophisticated switching technology based on optoelectric gallium arsenide elements. The haptic information which is represented at the actuator array can be transferred from a corresponding sensor system based on ultrasonic elastography. The combined sensor-actuator system may serve as a technology platform for various applications in virtual reality, like telemedicine where the information on the consistency of tissue of a real patient is detected by the sensor part and recorded by the actuator part at a remote location.

  2. Cavity opto-electromechanical system combining strong electrical actuation with ultrasensitive transduction

    OpenAIRE

    McRae, Terry G.; Lee, Kwan H.; Harris, Glen I.; Knittel, Joachim; Bowen, Warwick P.

    2010-01-01

    A cavity opto-electromechanical system is reported which combines the ultrasensitive transduction of cavity optomechanical systems with the electrical actuation of nanoelectromechanical systems. Ultrasensitive mechanical transduction is achieved via opto-mechanical coupling. Electrical gradient forces as large as 0.40 $\\mu$N are realized, facilitating strong actuation with ultralow dissipation. A scanning probe microscope is implemented, capable of characterizing the mechanical modes. The int...

  3. Reactor protection system

    International Nuclear Information System (INIS)

    Fairbrother, D.B.; Lesniak, L.M.; Orgera, E.G.

    1977-10-01

    The report describes the reactor protection system (RPS-II) designed for use on Babcock and Wilcox 145-, later 177-, and 205-fuel assembly pressurized water reactors. In this system, relays in the trip logic have been replaced by solid state devices. A calculating module for the low DNBR, pump status, and offset trip functions has replaced the overpower trip (based on flow and imbalance), the power/RC pump trip, and the variable low-pressure trip. Included is a description of the changes from the present Oconee-type reactor protection system (RPS-I), a functional and hardware description of the calculating module, a description of the software programmed in the calculating module, and a discussion of the qualification program conducted to ensure that the degree of protection provided by RPS-II is not less than that provided by previously licensed systems supplied by B and W

  4. Smart Machine Protection System

    International Nuclear Information System (INIS)

    Clark, S.; Nelson, D.; Grillo, A.; Spencer, N.; Hutchinson, D.; Olsen, J.; Millsom, D.; White, G.; Gromme, T.; Allison, S.; Underwood, K.; Zelazny, M.; Kang, H.

    1991-11-01

    A Machine Protection System implemented on the SLC automatically controls the beam repetition rates in the accelerator so that radiation or temperature faults slow the repetition rate to bring the fault within tolerance without shutting down the machine. This process allows the accelerator to aid in the fault diagnostic process, and the protection system automatically restores the beams back to normal rates when the fault is diagnosed and corrected. The user interface includes facilities to monitor the performance of the system, and track rate limits, faults, and recoveries. There is an edit facility to define the devices to be included in the protection system, along with their set points, limits, and trip points. This set point and limit data is downloaded into the CAMAC modules, and the configuration data is compiled into a logical decision tree for the 68030 processor. 3 figs

  5. Smart machine protection system

    International Nuclear Information System (INIS)

    Clark, S.; Nelson, D.; Grillo, A.

    1992-01-01

    A Machine Protection System implemented on the SLC automatically controls the beam repetition rates in the accelerator so that radiation or temperature faults slow the repetition rate to bring the fault within tolerance without shutting down the machine. This process allows the accelerators to aid in the fault diagnostic process, and the protection system automatically restores the beams back to normal rates when the fault is diagnosed and corrected. The user interface includes facilities to monitor the performance of the system, and track rate limits, faults, and recoveries. There is an edit facility to define the devices to be included in the protection system, along with their set points, limits, and trip points. This set point and limit data is downloaded into the CAMAC modules, and the configuration data is complied into a logical decision tree for the 68030 processor. (author)

  6. Verification of operation of the actuator control system using the integration the B&R Automation Studio software with a virtual model of the actuator system

    Science.gov (United States)

    Herbuś, K.; Ociepka, P.

    2017-08-01

    In the work is analysed a sequential control system of a machine for separating and grouping work pieces for processing. Whereas, the area of the considered problem is related with verification of operation of an actuator system of an electro-pneumatic control system equipped with a PLC controller. Wherein to verification is subjected the way of operation of actuators in view of logic relationships assumed in the control system. The actuators of the considered control system were three drives of linear motion (pneumatic cylinders). And the logical structure of the system of operation of the control system is based on the signals flow graph. The tested logical structure of operation of the electro-pneumatic control system was implemented in the Automation Studio software of B&R company. This software is used to create programs for the PLC controllers. Next, in the FluidSIM software was created the model of the actuator system of the control system of a machine. To verify the created program for the PLC controller, simulating the operation of the created model, it was utilized the approach of integration these two programs using the tool for data exchange in the form of the OPC server.

  7. Temporary physical protection systems

    International Nuclear Information System (INIS)

    Williams, J.D.; Gangel, D.J.; Madsen, R.W.

    1991-01-01

    Terrorism and other aspects of world political instability have created a high demand for temporary physical protection systems within the nuclear materials management community. They can be used when vehicles carrying important assets are away from their permanent fixed site location, around areas where experiments are being temporarily conducted, around construction areas and one portions of a fixed site physical security system which is temporarily inoperable. Physical security systems can be grouped into four categories: tactical, portable, semi-permanent, and fixed. The resources and experience gained at Sandia National Laboratories in over forty years of developing and implementing security systems for protecting nuclear weapons and fixed nuclear facilities is now being applied to temporary physical security systems. This paper emphasizes temporary physical security systems and their component parts that are presently available and identify additional system-subsystem objectives, requirements, and concepts

  8. Reliability analysis of self-actuated shutdown system

    International Nuclear Information System (INIS)

    Itooka, S.; Kumasaka, K.; Okabe, A.; Satoh, K.; Tsukui, Y.

    1991-01-01

    An analytical study was performed for the reliability of a self-actuated shutdown system (SASS) under the unprotected loss of flow (ULOF) event in a typical loop-type liquid metal fast breeder reactor (LMFBR) by the use of the response surface Monte Carlo analysis method. Dominant parameters for the SASS, such as Curie point characteristics, subassembly outlet coolant temperature, electromagnetic surface condition, etc., were selected and their probability density functions (PDFs) were determined by the design study information and experimental data. To get the response surface function (RSF) for the maximum coolant temperature, transient analyses of ULOF were performed by utilizing the experimental design method in the determination of analytical cases. Then, the RSF was derived by the multi-variable regression analysis. The unreliability of the SASS was evaluated as a probability that the maximum coolant temperature exceeded an acceptable level, employing the Monte Carlo calculation using the above PDFs and RSF. In this study, sensitivities to the dominant parameter were compared. The dispersion of subassembly outlet coolant temperature near the SASS-was found to be one of the most sensitive parameters. Fault tree analysis was performed using this value for the SASS in order to evaluate the shutdown system reliability. As a result of this study, the effectiveness of the SASS on the reliability improvement in the LMFBR shutdown system was analytically confirmed. This study has been performed as a part of joint research and development projects for DFBR under the sponsorship of the nine Japanese electric power companies, Electric Power Development Company and the Japan Atomic Power Company. (author)

  9. 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....

  10. Experimental StudyHigh Altitude Forced Convective Cooling of Electromechanical Actuation Systems

    Science.gov (United States)

    2016-01-01

    34 Massachusetts Institute of Technology , 1989. [3] FedBizOps.Gov, " Integrated Vehicle Energy Technology (INVENT) Development Program for the 6th...AFRL-RQ-WP-TR-2016-0043 EXPERIMENTAL STUDY—HIGH ALTITUDE FORCED CONVECTIVE COOLING OF ELECTROMECHANICAL ACTUATION SYSTEMS Evan M. Racine...TITLE AND SUBTITLE EXPERIMENTAL STUDY—HIGH ALTITUDE FORCED CONVECTIVE COOLING OF ELECTROMECHANICAL ACTUATION SYSTEMS 5a. CONTRACT NUMBER In-house

  11. Advanced worker protection system

    International Nuclear Information System (INIS)

    Caldwell, B.; Duncan, P.; Myers, J.

    1995-01-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D ampersand D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D ampersand D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D ampersand D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project will result in the development of an Advanced Worker Protection System (AWPS). The AWPS will be built around a life support backpack that uses liquid air to provide cooling as well as breathing gas to the worker. The backpack will be combined with advanced protective garments, advanced liquid cooling garment, respirator, communications, and support equipment to provide improved worker protection, simplified system maintenance, and dramatically improve worker productivity through longer duration work cycles. Phase I of the project has resulted in a full scale prototype Advanced Worker Protection Ensemble (AWPE, everything the worker will wear), with sub-scale support equipment, suitable for integrated testing and preliminary evaluation. Phase II will culminate in a full scale, certified, pre-production AWPS and a site demonstration

  12. Advanced worker protection system

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, B.; Duncan, P.; Myers, J.

    1995-12-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D&D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D&D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D&D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project will result in the development of an Advanced Worker Protection System (AWPS). The AWPS will be built around a life support backpack that uses liquid air to provide cooling as well as breathing gas to the worker. The backpack will be combined with advanced protective garments, advanced liquid cooling garment, respirator, communications, and support equipment to provide improved worker protection, simplified system maintenance, and dramatically improve worker productivity through longer duration work cycles. Phase I of the project has resulted in a full scale prototype Advanced Worker Protection Ensemble (AWPE, everything the worker will wear), with sub-scale support equipment, suitable for integrated testing and preliminary evaluation. Phase II will culminate in a full scale, certified, pre-production AWPS and a site demonstration.

  13. Design and control of electromagnetic clutch actuation system for automated manual transmission

    Science.gov (United States)

    Ranjan, Ashish; Prasanth, S.; Cherian, Fenin; Baskar, P.

    2017-11-01

    There is a growing interest towards Automatic Transmission in India as it provides better comfort and drivability. But the high cost of this system is limiting itself to be successful in the Indian markets. Due to this, Automated Manual Transmission (AMT) is considered which provides a better solution towards automation as it enhances the drivability and fuel consumption characteristics of a manual transmission at lower costs. However, torque lag and comfort are major issues with AMT which can be addressed by reducing the shift time. In this paper we describe an Electromagnetic Linear Clutch Actuator as a replacement to current electrohydraulic and electromechanical actuator. A control system for the actuator is presented and a clutch engagement strategy is also implemented which reduces the engagement time to 0.78 seconds while reducing jerk and torque lag. The actuator and control system is simulated on a MATLAB Simulink and agreeable results have been obtained.

  14. Digital integrated protection system

    International Nuclear Information System (INIS)

    Savornin, M.; Furet, M.

    1978-01-01

    As a result of technological progress it is now possible to achieve more elaborate protection functions able to follow more closely the phenomena to be supervised. For this reason the CEA, Framatome and Merlin/Gerin/CERCI have undertaken in commonn to develop a Digital Integrated Protection System (D.I.P.S.). This system is designed with the following aims: to improve the safety of the station, . to improve its availability, . to facilitate installation, . to facilitate tests and maintenance. The main characteristics adopted are: . possibilities of obtaining more elaborate monitoring and protection algorithm treatments, . order 4 redundancy of transducers, associated instruments and signal processing, . possibility of inhibiting part of the protection system, . standardisation of equipment, physical and electrical separation of redundant units, . use of multiplexed connections, . automation of tests. Four flow charts are presented: - DIPS with four APUP (Acquisition and Processing Unit for Protection) - APUP - LSU (Logic Safeguard Unit), number LSU corresponding to number fluidic safeguard circuits, - structure of a function unit, - main functions of the APUP [fr

  15. Technical evaluation of the noise and isolation testing of the safety features actuation system at the Davis Besse Nuclear Power Station, Unit 1

    International Nuclear Information System (INIS)

    Selan, J.C.

    1981-07-01

    This report documents the technical evaluation of the noise and isolation testing of the safety features actuation system at the Davis Besse Nuclear Power Station, Unit 1. The tests were to verify that faults on the non-Class 1E circuits would not propagate to the Class 1E circuits and degrade them below acceptable levels. The tests conducted demonstrated that the safety features actuation system did not degrade below acceptable levels nor was the system's ability to perform its protective functions affected

  16. Advanced worker protection system

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, B.; Duncan, P.; Myers, J. [Oceaneering Space Systems, Houston, TX (United States)

    1995-10-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D&D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D&D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D&D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project describes the development of an Advanced Worker Protection System (AWPS) which will include a life-support backpack with liquid air for cooling and as a supply of breathing gas, protective clothing, respirators, communications, and support equipment.

  17. Advanced worker protection system

    International Nuclear Information System (INIS)

    Caldwell, B.; Duncan, P.; Myers, J.

    1995-01-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D ampersand D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D ampersand D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D ampersand D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project describes the development of an Advanced Worker Protection System (AWPS) which will include a life-support backpack with liquid air for cooling and as a supply of breathing gas, protective clothing, respirators, communications, and support equipment

  18. Improved core protection calculator system algorithm

    International Nuclear Information System (INIS)

    Yoon, Tae Young; Park, Young Ho; In, Wang Kee; Bae, Jong Sik; Baeg, Seung Yeob

    2009-01-01

    Core Protection Calculator System (CPCS) is a digitized core protection system which provides core protection functions based on two reactor core operation parameters, Departure from Nucleate Boiling Ratio (DNBR) and Local Power Density (LPD). It generates a reactor trip signal when the core condition exceeds the DNBR or LPD design limit. It consists of four independent channels which adapted a two out of four trip logic. CPCS algorithm improvement for the newly designed core protection calculator system, RCOPS (Reactor COre Protection System), is described in this paper. New features include the improvement of DNBR algorithm for thermal margin, the addition of pre trip alarm generation for auxiliary trip function, VOPT (Variable Over Power Trip) prevention during RPCS (Reactor Power Cutback System) actuation and the improvement of CEA (Control Element Assembly) signal checking algorithm. To verify the improved CPCS algorithm, CPCS algorithm verification tests, 'Module Test' and 'Unit Test', would be performed on RCOPS single channel facility. It is expected that the improved CPCS algorithm will increase DNBR margin and enhance the plant availability by reducing unnecessary reactor trips

  19. Development of a Novel Guided Wave Generation System Using a Giant Magnetostrictive Actuator for Nondestructive Evaluation.

    Science.gov (United States)

    Luo, Mingzhang; Li, Weijie; Wang, Junming; Wang, Ning; Chen, Xuemin; Song, Gangbing

    2018-03-04

    As a common approach to nondestructive testing and evaluation, guided wave-based methods have attracted much attention because of their wide detection range and high detection efficiency. It is highly desirable to develop a portable guided wave testing system with high actuating energy and variable frequency. In this paper, a novel giant magnetostrictive actuator with high actuation power is designed and implemented, based on the giant magnetostrictive (GMS) effect. The novel GMS actuator design involves a conical energy-focusing head that can focus the amplified mechanical energy generated by the GMS actuator. This design enables the generation of stress waves with high energy, and the focusing of the generated stress waves on the test object. The guided wave generation system enables two kinds of output modes: the coded pulse signal and the sweep signal. The functionality and the advantages of the developed system are validated through laboratory testing in the quality assessment of rock bolt-reinforced structures. In addition, the developed GMS actuator and the supporting system are successfully implemented and applied in field tests. The device can also be used in other nondestructive testing and evaluation applications that require high-power stress wave generation.

  20. Modeling and Simulation of Control Actuation System with Fuzzy-PID Logic Controlled Brushless Motor Drives for Missiles Glider Applications.

    Science.gov (United States)

    Muniraj, Murali; Arulmozhiyal, Ramaswamy

    2015-01-01

    A control actuation system has been used extensively in automotive, aerospace, and defense applications. The major challenges in modeling control actuation system are rise time, maximum peak to peak overshoot, and response to nonlinear system with percentage error. This paper addresses the challenges in modeling and real time implementation of control actuation system for missiles glider applications. As an alternative fuzzy-PID controller is proposed in BLDC motor drive followed by linkage mechanism to actuate fins in missiles and gliders. The proposed system will realize better rise time and less overshoot while operating in extreme nonlinear dynamic system conditions. A mathematical model of BLDC motor is derived in state space form. The complete control actuation system is modeled in MATLAB/Simulink environment and verified by performing simulation studies. A real time prototype of the control actuation is developed with dSPACE-1104 hardware controller and a detailed analysis is carried out to confirm the viability of the proposed system.

  1. Advanced Launch System (ALS): Electrical actuation and power systems improve operability and cost picture

    Science.gov (United States)

    Sundberg, Gale R.

    1990-01-01

    To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrical power system and controls for all actuation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a specific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military and civilian aircraft, lunar/Martian vehicles, and a multitude of commercial applications.

  2. Protective garment ventilation system

    Science.gov (United States)

    Lang, R. (Inventor)

    1970-01-01

    A method and apparatus for ventilating a protective garment, space suit system, and/or pressure suits to maintain a comfortable and nontoxic atmosphere within is described. The direction of flow of a ventilating and purging gas in portions of the garment may be reversed in order to compensate for changes in environment and activity of the wearer. The entire flow of the ventilating gas can also be directed first to the helmet associated with the garment.

  3. Three-dimensional Locomotion and Drilling Microrobot Using Electromagnetic Actuation System

    Energy Technology Data Exchange (ETDEWEB)

    Li, Girl; Choi, Hyun Chul; Cha, Kyoung Rae; Jeong, Se Mi; Park, Jong Oh; Park, Suk Ho [Chonnam National University, Gwangju (Korea, Republic of)

    2011-12-15

    In this study, a novel electromagnetic microrobot system with locomotion and drilling functions in three dimensional space was developed. Because of size limitations, the microrobot does not have actuator, battery, and controller. Therefore, an electromagnetic actuation (EMA) system was used to drive the robot. The proposed EMA system consists of three rectangular Helmholtz coil pairs in x-, y- and z-axes and a Maxwell coil pair in the z-axis. The magnetic field generated in the EMA coil system could be controlled by the input current of the EMA coil. Finally, through various experiments, the locomotion and drilling performances of the proposed EMA microrobot system were verified.

  4. Three-dimensional Locomotion and Drilling Microrobot Using Electromagnetic Actuation System

    International Nuclear Information System (INIS)

    Li, Girl; Choi, Hyun Chul; Cha, Kyoung Rae; Jeong, Se Mi; Park, Jong Oh; Park, Suk Ho

    2011-01-01

    In this study, a novel electromagnetic microrobot system with locomotion and drilling functions in three dimensional space was developed. Because of size limitations, the microrobot does not have actuator, battery, and controller. Therefore, an electromagnetic actuation (EMA) system was used to drive the robot. The proposed EMA system consists of three rectangular Helmholtz coil pairs in x-, y- and z-axes and a Maxwell coil pair in the z-axis. The magnetic field generated in the EMA coil system could be controlled by the input current of the EMA coil. Finally, through various experiments, the locomotion and drilling performances of the proposed EMA microrobot system were verified

  5. Reliability study: digital engineered safety feature actuation system of Korean Standard Nuclear Power Plant

    International Nuclear Information System (INIS)

    Sudarno; Kang, H. G.; Jang, S. C.; Eom, H. S.; Ha, J. J.

    2003-04-01

    The usage of digital Instrumentation and Control (I and C) in a nuclear power plant becomes more extensive, including safety related systems. The PSA application of these new designs are very important in order to evaluate their reliability. In particular, Korean Standard Nuclear Power Plants (KSNPPs), typically Ulchin 5 and 6 (UCN 5 and 6) reactor units, adopted the digital safety-critical systems such as Digital Plant Protection System (DPPS) and Digital Engineered Safety Feature Actuation System (DESFAS). In this research, we developed fault tree models for assessing the unavailability of the DESFAS functions. We also performed an analysis of the quantification results. The unavailability results of different DESFAS functions showed that their values are comprised from 5.461E-5 to 3.14E-4. The system unavailability of DESFAS AFAS-1 is estimated as 5.461E-5, which is about 27% less than that of analog system if we consider the difference of human failure probability estimation between both analyses. The results of this study could be utilized in risk-effect analysis of KSNPP. We expect that the safety analysis result will contribute to design feedback

  6. Strategic avionics technology definition studies. Subtask 3-1A: Electrical Actuation (ELA) systems

    Science.gov (United States)

    Pond, Charles L.; Mcdermott, William A.; Lum, Ben T. F.

    1993-01-01

    Electrical actuator (ELA) power efficiency and requirements are examined for space system application. Requirements for Space Shuttle effector systems are presented, along with preliminary ELA trades and selection to form a preliminary ELA system baseline. Power and energy requirements for this baseline ELA system are applicable to the Space Shuttle and similar space vehicles.

  7. Design of a linear-motion dual-stage actuation system for precision control

    International Nuclear Information System (INIS)

    Dong, W; Tang, J; ElDeeb, Y

    2009-01-01

    Actuators with high linear-motion speed, high positioning resolution and a long motion stroke are needed in many precision machining systems. In some current systems, voice coil motors (VCMs) are implemented for servo control. While the voice coil motors may provide the long motion stroke needed in many applications, the main obstacle that hinders the improvement of the machining accuracy and efficiency is their limited bandwidth. To fundamentally solve this issue, we propose to develop a dual-stage actuation system that consists of a voice coil motor that covers the coarse motion, and a piezoelectric stack actuator that induces the fine motion, thus enhancing the positioning accuracy. The focus of this present research is the mechatronics design and synthesis of the new actuation system. In particular, a flexure hinge based mechanism is developed to provide a motion guide and preload to the piezoelectric stack actuator that is serially connected to the voice coil motor. This mechanism is built upon parallel plane flexure hinges. A series of numerical and experimental studies are carried out to facilitate the system design and the model identification. The effectiveness of the proposed system is demonstrated through open-loop studies and preliminary closed-loop control practice. While the primary goal of this particular design is aimed at enhancing optical lens machining, the concept and approach outlined are generic and can be extended to a variety of applications

  8. Design and simulation of a new bidirectional actuator for haptic systems featuring MR fluid

    Science.gov (United States)

    Hung, Nguyen Quoc; Tri, Diep Bao; Cuong, Vo Van; Choi, Seung-Bok

    2017-04-01

    In this research, a new configuration of bidirectional actuator featuring MR fluid (BMRA) is proposed for haptic application. The proposed BMRA consists of a driving disc, a driving housing and a driven disc. The driving disc is placed inside the driving housing and rotates counter to each other by a servo DC motor and a bevel gear system. The driven shaft is also placed inside the housing and next to the driving disc. The gap between the two disc and the gap between the discs and the housing are filled with MR fluid. On the driven disc, two mutual magnetic coils are placed. By applying currents to the two coils mutually, the torque at the output shaft, which is fixed to the driven disc, can be controlled with positive, zero or negative value. This make the actuator be suitable for haptic application. After a review of MR fluid and its application, configuration of the proposed BMRA is presented. The modeling of the actuator is then derived based on Bingham rheological model of MRF and magnetic finite element analysis (FEA). The optimal design of the actuator is then performed to minimize the mass of the BMRA. From the optimal design result, performance characteristics of the actuator is simulated and detailed design of a prototype actuator is conducted.

  9. Sensor and Actuator Fault-Hiding Reconfigurable Control Design for a Four-Tank System Benchmark

    DEFF Research Database (Denmark)

    Hameed, Ibrahim; El-Madbouly, Esam I; Abdo, Mohamed I

    2015-01-01

    Invariant (LTI) system where virtual sensors and virtual actuators are used to correct faulty performance through the use of a pre-fault performance. Simulation results showed that the developed approach can handle different types of faults and able to completely and instantly recover the original system......Fault detection and compensation plays a key role to fulfill high demands for performance and security in today's technological systems. In this paper, a fault-hiding (i.e., tolerant) control scheme that detects and compensates for actuator and sensor faults in a four-tank system benchmark...

  10. 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

  11. Pneumatic Rotary Actuator Position Servo System Based on ADE-PD Control

    Directory of Open Access Journals (Sweden)

    Yeming Zhang

    2018-03-01

    Full Text Available In order to accurately control the rotation position of a pneumatic rotary actuator, the flow state of the gas and the motion state of the pneumatic rotary actuator in the pneumatic rotary actuator position servo system are analyzed in this paper. The mathematical model of the system and the experiment platform are established after that. An Adaptive Differential Evolution (ADE algorithm which adaptively ameliorates the scaling factor and crossover probability in the process of individual evolution is proposed and applied to the parameter optimization of PD controller. The experimental platform is used to compare the controller with Differential Evolution (DE algorithm and NCD-PID controller. Finally, the characteristics of the system are tested by increasing the inertial load. The experimental results illustrate that system using ADE-PD control strategy has greater position precision and faster response than using DE-PD and NCD-PID strategies, and shows great robustness.

  12. An optimal control strategy for hybrid actuator systems: Application to an artificial muscle with electric motor assist.

    Science.gov (United States)

    Ishihara, Koji; Morimoto, Jun

    2018-03-01

    Humans use multiple muscles to generate such joint movements as an elbow motion. With multiple lightweight and compliant actuators, joint movements can also be efficiently generated. Similarly, robots can use multiple actuators to efficiently generate a one degree of freedom movement. For this movement, the desired joint torque must be properly distributed to each actuator. One approach to cope with this torque distribution problem is an optimal control method. However, solving the optimal control problem at each control time step has not been deemed a practical approach due to its large computational burden. In this paper, we propose a computationally efficient method to derive an optimal control strategy for a hybrid actuation system composed of multiple actuators, where each actuator has different dynamical properties. We investigated a singularly perturbed system of the hybrid actuator model that subdivided the original large-scale control problem into smaller subproblems so that the optimal control outputs for each actuator can be derived at each control time step and applied our proposed method to our pneumatic-electric hybrid actuator system. Our method derived a torque distribution strategy for the hybrid actuator by dealing with the difficulty of solving real-time optimal control problems. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

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

    OpenAIRE

    V. N. Pilgunov; K. D. Efremova

    2016-01-01

    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 con...

  14. WASTE HANDLING BUILDING FIRE PROTECTION SYSTEM DESCRIPTION DOCUMENT

    Energy Technology Data Exchange (ETDEWEB)

    J. D. Bigbee

    2000-06-21

    The Waste Handling Building Fire Protection System provides the capability to detect, control, and extinguish fires and/or mitigate explosions throughout the Waste Handling Building (WHB). Fire protection includes appropriate water-based and non-water-based suppression, as appropriate, and includes the distribution and delivery systems for the fire suppression agents. The Waste Handling Building Fire Protection System includes fire or explosion detection panel(s) controlling various detectors, system actuation, annunciators, equipment controls, and signal outputs. The system interfaces with the Waste Handling Building System for mounting of fire protection equipment and components, location of fire suppression equipment, suppression agent runoff, and locating fire rated barriers. The system interfaces with the Waste Handling Building System for adequate drainage and removal capabilities of liquid runoff resulting from fire protection discharges. The system interfaces with the Waste Handling Building Electrical Distribution System for power to operate, and with the Site Fire Protection System for fire protection water supply to automatic sprinklers, standpipes, and hose stations. The system interfaces with the Site Fire Protection System for fire signal transmission outside the WHB as needed to respond to a fire emergency, and with the Waste Handling Building Ventilation System to detect smoke and fire in specific areas, to protect building high-efficiency particulate air (HEPA) filters, and to control portions of the Waste Handling Building Ventilation System for smoke management and manual override capability. The system interfaces with the Monitored Geologic Repository (MGR) Operations Monitoring and Control System for annunciation, and condition status.

  15. WASTE HANDLING BUILDING FIRE PROTECTION SYSTEM DESCRIPTION DOCUMENT

    International Nuclear Information System (INIS)

    J. D. Bigbee

    2000-01-01

    The Waste Handling Building Fire Protection System provides the capability to detect, control, and extinguish fires and/or mitigate explosions throughout the Waste Handling Building (WHB). Fire protection includes appropriate water-based and non-water-based suppression, as appropriate, and includes the distribution and delivery systems for the fire suppression agents. The Waste Handling Building Fire Protection System includes fire or explosion detection panel(s) controlling various detectors, system actuation, annunciators, equipment controls, and signal outputs. The system interfaces with the Waste Handling Building System for mounting of fire protection equipment and components, location of fire suppression equipment, suppression agent runoff, and locating fire rated barriers. The system interfaces with the Waste Handling Building System for adequate drainage and removal capabilities of liquid runoff resulting from fire protection discharges. The system interfaces with the Waste Handling Building Electrical Distribution System for power to operate, and with the Site Fire Protection System for fire protection water supply to automatic sprinklers, standpipes, and hose stations. The system interfaces with the Site Fire Protection System for fire signal transmission outside the WHB as needed to respond to a fire emergency, and with the Waste Handling Building Ventilation System to detect smoke and fire in specific areas, to protect building high-efficiency particulate air (HEPA) filters, and to control portions of the Waste Handling Building Ventilation System for smoke management and manual override capability. The system interfaces with the Monitored Geologic Repository (MGR) Operations Monitoring and Control System for annunciation, and condition status

  16. ADVANCED WORKER PROTECTION SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Judson Hedgehock

    2001-03-16

    From 1993 to 2000, OSS worked under a cost share contract from the Department of Energy (DOE) to develop an Advanced Worker Protection System (AWPS). The AWPS is a protective ensemble that provides the user with both breathing air and cooling for a NIOSH-rated duration of two hours. The ensemble consists of a liquid air based backpack, a Liquid Cooling Garment (LCG), and an outer protective garment. The AWPS project was divided into two phases. During Phase 1, OSS developed and tested a full-scale prototype AWPS. The testing showed that workers using the AWPS could work twice as long as workers using a standard SCBA. The testing also provided performance data on the AWPS in different environments that was used during Phase 2 to optimize the design. During Phase 1, OSS also performed a life-cycle cost analysis on a representative clean up effort. The analysis indicated that the AWPS could save the DOE millions of dollars on D and D activities and improve the health and safety of their workers. During Phase 2, OSS worked to optimize the AWPS design to increase system reliability, to improve system performance and comfort, and to reduce the backpack weight and manufacturing costs. To support this design effort, OSS developed and tested several different generations of prototype units. Two separate successful evaluations of the ensemble were performed by the International Union of Operation Engineers (IUOE). The results of these evaluations were used to drive the design. During Phase 2, OSS also pursued certifying the AWPS with the applicable government agencies. The initial intent during Phase 2 was to finalize the design and then to certify the system. OSS and Scott Health and Safety Products teamed to optimize the AWPS design and then certify the system with the National Institute of Occupational Health and Safety (NIOSH). Unfortunately, technical and programmatic difficulties prevented us from obtaining NIOSH certification. Despite the inability of NIOSH to certify

  17. ADVANCED WORKER PROTECTION SYSTEM

    International Nuclear Information System (INIS)

    Judson Hedgehock

    2001-01-01

    From 1993 to 2000, OSS worked under a cost share contract from the Department of Energy (DOE) to develop an Advanced Worker Protection System (AWPS). The AWPS is a protective ensemble that provides the user with both breathing air and cooling for a NIOSH-rated duration of two hours. The ensemble consists of a liquid air based backpack, a Liquid Cooling Garment (LCG), and an outer protective garment. The AWPS project was divided into two phases. During Phase 1, OSS developed and tested a full-scale prototype AWPS. The testing showed that workers using the AWPS could work twice as long as workers using a standard SCBA. The testing also provided performance data on the AWPS in different environments that was used during Phase 2 to optimize the design. During Phase 1, OSS also performed a life-cycle cost analysis on a representative clean up effort. The analysis indicated that the AWPS could save the DOE millions of dollars on D and D activities and improve the health and safety of their workers. During Phase 2, OSS worked to optimize the AWPS design to increase system reliability, to improve system performance and comfort, and to reduce the backpack weight and manufacturing costs. To support this design effort, OSS developed and tested several different generations of prototype units. Two separate successful evaluations of the ensemble were performed by the International Union of Operation Engineers (IUOE). The results of these evaluations were used to drive the design. During Phase 2, OSS also pursued certifying the AWPS with the applicable government agencies. The initial intent during Phase 2 was to finalize the design and then to certify the system. OSS and Scott Health and Safety Products teamed to optimize the AWPS design and then certify the system with the National Institute of Occupational Health and Safety (NIOSH). Unfortunately, technical and programmatic difficulties prevented us from obtaining NIOSH certification. Despite the inability of NIOSH to certify

  18. Strategic avionics technology definition studies. Subtask 3-1A3: Electrical Actuation (ELA) Systems Test Facility

    Science.gov (United States)

    Rogers, J. P.; Cureton, K. L.; Olsen, J. R.

    1994-01-01

    Future aerospace vehicles will require use of the Electrical Actuator systems for flight control elements. This report presents a proposed ELA Test Facility for dynamic evaluation of high power linear Electrical Actuators with primary emphasis on Thrust Vector Control actuators. Details of the mechanical design, power and control systems, and data acquisition capability of the test facility are presented. A test procedure for evaluating the performance of the ELA Test Facility is also included.

  19. Actuator digital interface unit (AIU). [control units for space shuttle data system

    Science.gov (United States)

    1973-01-01

    Alternate versions of the actuator interface unit are presented. One alternate is a dual-failure immune configuration which feeds a look-and-switch dual-failure immune hydraulic system. The other alternate is a single-failure immune configuration which feeds a majority voting hydraulic system. Both systems communicate with the data bus through data terminals dedicated to each user subsystem. Both operational control data and configuration control information are processed in and out of the subsystem via the data terminal which yields the actuator interface subsystem, self-managing within its failure immunity capability.

  20. Self-actuated shutdown system for a commercial size LMFBR. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Dupen, C.F.G.

    1978-08-01

    A Self-Actuated Shutdown System (SASS) is defined as a reactor shutdown system in which sensors, release mechanisms and neutron absorbers are contained entirely within the reactor core structure, where they respond inherently to abnormal local process conditions, by shutting down the reactor, independently of the plant protection system (PPS). It is argued that a SASS, having a response time similar to that of the PPS, would so reduce the already very low probability of a failure-to-scram event that costly design features, derived from core disruptive accident analysis, could be eliminated. However, the thrust of the report is the feasibility and reliability of the in-core SASS hardware to achieve sufficiently rapid shutdown. A number of transient overpower and transient undercooling-responsive systems were investigated leading to the selection of a primary candidate and a backup concept. During a transient undercooling event, the recommended device is triggered by the associated rate of change of pressure, whereas the alternate concept responds to the reduction in core pressure drop and requires calibration and adjustment by the operators to accommodate changes in reactor power.

  1. Self-actuated shutdown system for a commercial size LMFBR. Final report

    International Nuclear Information System (INIS)

    Dupen, C.F.G.

    1978-08-01

    A Self-Actuated Shutdown System (SASS) is defined as a reactor shutdown system in which sensors, release mechanisms and neutron absorbers are contained entirely within the reactor core structure, where they respond inherently to abnormal local process conditions, by shutting down the reactor, independently of the plant protection system (PPS). It is argued that a SASS, having a response time similar to that of the PPS, would so reduce the already very low probability of a failure-to-scram event that costly design features, derived from core disruptive accident analysis, could be eliminated. However, the thrust of the report is the feasibility and reliability of the in-core SASS hardware to achieve sufficiently rapid shutdown. A number of transient overpower and transient undercooling-responsive systems were investigated leading to the selection of a primary candidate and a backup concept. During a transient undercooling event, the recommended device is triggered by the associated rate of change of pressure, whereas the alternate concept responds to the reduction in core pressure drop and requires calibration and adjustment by the operators to accommodate changes in reactor power

  2. Design and Calibration of an RF Actuator for Low-Level RF Systems

    Science.gov (United States)

    Geng, Zheqiao; Hong, Bo

    2016-02-01

    X-ray free electron laser (FEL) machines like the Linac Coherent Light Source (LCLS) at SLAC require high-quality electron beams to generate X-ray lasers for various experiments. Digital low-level RF (LLRF) systems are widely used to control the high-power RF klystrons to provide a highly stable RF field in accelerator structures for beam acceleration. Feedback and feedforward controllers are implemented in LLRF systems to stabilize or adjust the phase and amplitude of the RF field. To achieve the RF stability and the accuracy of the phase and amplitude adjustment, low-noise and highly linear RF actuators are required. Aiming for the upgrade of the S-band Linac at SLAC, an RF actuator is designed with an I/Qmodulator driven by two digital-to-analog converters (DAC) for the digital LLRF systems. A direct upconversion scheme is selected for RF actuation, and an on-line calibration algorithm is developed to compensate the RF reference leakage and the imbalance errors in the I/Q modulator, which may cause significant phase and amplitude actuation errors. This paper presents the requirements on the RF actuator, the design of the hardware, the calibration algorithm, and the implementation in firmware and software and the test results at LCLS.

  3. Bioinspired Soft Actuation System Using Shape Memory Alloys

    Directory of Open Access Journals (Sweden)

    Matteo Cianchetti

    2014-07-01

    Full Text Available Soft robotics requires technologies that are capable of generating forces even though the bodies are composed of very light, flexible and soft elements. A soft actuation mechanism was developed in this work, taking inspiration from the arm of the Octopus vulgaris, specifically from the muscular hydrostat which represents its constitutive muscular structure. On the basis of the authors’ previous works on shape memory alloy (SMA springs used as soft actuators, a specific arrangement of such SMA springs is presented, which is combined with a flexible braided sleeve featuring a conical shape and a motor-driven cable. This robot arm is able to perform tasks in water such as grasping, multi-bending gestures, shortening and elongation along its longitudinal axis. The whole structure of the arm is described in detail and experimental results on workspace, bending and grasping capabilities and generated forces are presented. Moreover, this paper demonstrates that it is possible to realize a self-contained octopus-like robotic arm with no rigid parts, highly adaptable and suitable to be mounted on underwater vehicles. Its softness allows interaction with all types of objects with very low risks of damage and limited safety issues, while at the same time producing relatively high forces when necessary.

  4. Vibration control of a camera mount system for an unmanned aerial vehicle using piezostack actuators

    International Nuclear Information System (INIS)

    Oh, Jong-Seok; Choi, Seung-Bok; Han, Young-Min

    2011-01-01

    This work proposes an active mount for the camera systems of unmanned aerial vehicles (UAV) in order to control unwanted vibrations. An active actuator of the proposed mount is devised as an inertial type, in which a piezostack actuator is directly connected to the inertial mass. After evaluating the actuating force of the actuator, it is combined with the rubber element of the mount, whose natural frequency is determined based on the measured vibration characteristics of UAV. Based on the governing equations of motion of the active camera mount, a robust sliding mode controller (SMC) is then formulated with consideration of parameter uncertainties and hysteresis behavior of the actuator. Subsequently, vibration control performances of the proposed active mount are experimentally evaluated in the time and frequency domains. In addition, a full camera mount system of UAVs that is supported by four active mounts is considered and its vibration control performance is evaluated in the frequency domain using a hardware-in-the-loop simulation (HILS) method

  5. Robust control for spacecraft rendezvous system with actuator unsymmetrical saturation: a gain scheduling approach

    Science.gov (United States)

    Wang, Qian; Xue, Anke

    2018-06-01

    This paper has proposed a robust control for the spacecraft rendezvous system by considering the parameter uncertainties and actuator unsymmetrical saturation based on the discrete gain scheduling approach. By changing of variables, we transform the actuator unsymmetrical saturation control problem into a symmetrical one. The main advantage of the proposed method is improving the dynamic performance of the closed-loop system with a region of attraction as large as possible. By the Lyapunov approach and the scheduling technology, the existence conditions for the admissible controller are formulated in the form of linear matrix inequalities. The numerical simulation illustrates the effectiveness of the proposed method.

  6. Systems approach to tamper protection

    International Nuclear Information System (INIS)

    Myre, W.C.; Eaton, M.J.

    1980-01-01

    Tamper-protection is a fundamental requirement of effective containment and surveillance systems. Cost effective designs require that the tamper protection requirements be considered early in the design phase and at the system level. A discussion of tamper protection alternatives as well as an illustrative example system is presented

  7. INTEGRATED DRILLING SYSTEM USING MUD ACTUATED DOWN HOLE HAMMER AS PRIMARY ENGINE

    Energy Technology Data Exchange (ETDEWEB)

    John V. Fernandez; David S. Pixton

    2005-12-01

    A history and project summary of the development of an integrated drilling system using a mud-actuated down-hole hammer as its primary engine are given. The summary includes laboratory test results, including atmospheric tests of component parts and simulated borehole tests of the hammer system. Several remaining technical hurdles are enumerated. A brief explanation of commercialization potential is included. The primary conclusion for this work is that a mud actuated hammer can yield substantial improvements to drilling rate in overbalanced, hard rock formations. A secondary conclusion is that the down-hole mud actuated hammer can serve to provide other useful down-hole functions including generation of high pressure mud jets, generation of seismic and sonic signals, and generation of diagnostic information based on hammer velocity profiles.

  8. Powered Upper Limb Orthosis Actuation System Based on Pneumatic Artificial Muscles

    Science.gov (United States)

    Chakarov, Dimitar; Veneva, Ivanka; Tsveov, Mihail; Venev, Pavel

    2018-03-01

    The actuation system of a powered upper limb orthosis is studied in the work. To create natural safety in the mutual "man-robot" interaction, an actuation system based on pneumatic artificial muscles (PAM) is selected. Experimentally obtained force/contraction diagrams for bundles, consisting of different number of muscles are shown in the paper. The pooling force and the stiffness of the pneumatic actuators is assessed as a function of the number of muscles in the bundle and the supply pressure. Joint motion and torque is achieved by antagonistic actions through pulleys, driven by bundles of pneumatic muscles. Joint stiffness and joint torques are determined on condition of a power balance, as a function of the joint position, pressure, number of muscles and muscles

  9. Improving control and estimation for distributed parameter systems utilizing mobile actuator-sensor network.

    Science.gov (United States)

    Mu, Wenying; Cui, Baotong; Li, Wen; Jiang, Zhengxian

    2014-07-01

    This paper proposes a scheme for non-collocated moving actuating and sensing devices which is unitized for improving performance in distributed parameter systems. By Lyapunov stability theorem, each moving actuator/sensor agent velocity is obtained. To enhance state estimation of a spatially distributes process, two kinds of filters with consensus terms which penalize the disagreement of the estimates are considered. Both filters can result in the well-posedness of the collective dynamics of state errors and can converge to the plant state. Numerical simulations demonstrate that the effectiveness of such a moving actuator-sensor network in enhancing system performance and the consensus filters converge faster to the plant state when consensus terms are included. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  10. Neuroadaptive Fault-Tolerant Control of Nonlinear Systems Under Output Constraints and Actuation Faults.

    Science.gov (United States)

    Zhao, Kai; Song, Yongduan; Shen, Zhixi

    2018-02-01

    In this paper, a neuroadaptive fault-tolerant tracking control method is proposed for a class of time-delay pure-feedback systems in the presence of external disturbances and actuation faults. The proposed controller can achieve prescribed transient and steady-state performance, despite uncertain time delays and output constraints as well as actuation faults. By combining a tangent barrier Lyapunov-Krasovskii function with the dynamic surface control technique, the neural network unit in the developed control scheme is able to take its action from the very beginning and play its learning/approximating role safely during the entire system operational envelope, leading to enhanced control performance without the danger of violating compact set precondition. Furthermore, prescribed transient performance and output constraints are strictly ensured in the presence of nonaffine uncertainties, external disturbances, and undetectable actuation faults. The control strategy is also validated by numerical simulation.

  11. Torque And Speed in the Actuating of Mechatronic Systems, a Case Study

    Directory of Open Access Journals (Sweden)

    Constantin Paul Roman

    2015-12-01

    Full Text Available The paper presents a mechatronic system programmed and controlled by a PLC and inverter for driving an AC motor. Torque and speed for part of mechatronic systems depends of actuating source for cinematic structure. In our research, mechanical structure consists of an AC motor. A technique for setting and control of speed and torque is presented.

  12. Multi-Axis Independent Electromechanical Load Control for Docking System Actuation Development and Verification Using dSPACE

    Science.gov (United States)

    Oesch, Christopher; Dick, Brandon; Rupp, Timothy

    2015-01-01

    The development of highly complex and advanced actuation systems to meet customer demands has accelerated as the use of real-time testing technology expands into multiple markets at Moog. Systems developed for the autonomous docking of human rated spacecraft to the International Space Station (ISS), envelope multi-operational characteristics which place unique constraints on an actuation system. Real-time testing hardware has been used as a platform for incremental testing and development for the linear actuation system which controls initial capture and docking for vehicles visiting the ISS. This presentation will outline the role of dSPACE hardware as a platform for rapid control-algorithm prototyping as well as an Electromechanical Actuator (EMA) system dynamic loading simulator, both conducted at Moog to develop the safety critical Linear Actuator System (LAS) of the NASA Docking System (NDS).

  13. Control rod blow out protection system

    International Nuclear Information System (INIS)

    Dietrich, J.R.; Flinn, W.S.; Groves, M.D.

    1976-01-01

    A control system is described which is comprised of a plurality of low worth absorber elements with individual hydraulic actuator assemblies, positioned within the reactor vessel. Axial distortions and safety hazards are minimized by this arrangement. (E.C.B.)

  14. Hydraulic engine valve actuation system including independent feedback control

    Science.gov (United States)

    Marriott, Craig D

    2013-06-04

    A hydraulic valve actuation assembly may include a housing, a piston, a supply control valve, a closing control valve, and an opening control valve. The housing may define a first fluid chamber, a second fluid chamber, and a third fluid chamber. The piston may be axially secured to an engine valve and located within the first, second and third fluid chambers. The supply control valve may control a hydraulic fluid supply to the piston. The closing control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the second fluid chamber to the supply control valve. The opening control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the supply control valve to the second fluid chamber.

  15. Ablative thermal protection systems

    International Nuclear Information System (INIS)

    Vaniman, J.; Fisher, R.; Wojciechowski, C.; Dean, W.

    1983-01-01

    The procedures used to establish the TPS (thermal protection system) design of the SRB (solid rocket booster) element of the Space Shuttle vehicle are discussed. A final evaluation of the adequacy of this design will be made from data obtained from the first five Shuttle flights. Temperature sensors installed at selected locations on the SRB structure covered by the TPS give information as a function of time throughout the flight. Anomalies are to be investigated and computer design thermal models adjusted if required. In addition, the actual TPS ablator material loss is to be measured after each flight and compared with analytically determined losses. The analytical methods of predicting ablator performance are surveyed. 5 references

  16. A novel magnetic suspension cum linear actuator system for satellite cryo coolers

    International Nuclear Information System (INIS)

    Sivadasan, K.K.

    1994-01-01

    Stirling cycle cryogenic coolers have been widely used for device cooling in satellites. Various types of magnetic bearings and linear actuators find application in such systems. The most widely used configurations have two-axis-radially-active suspension stations placed at either ends of a reciprocating shaft in the compression and expansion sections. Separate or integral liner motors are provided in each section for axial shaft movement. It may be noted that such configurations are rather complicated and less reliable because of the presence of numerous electro-mechanical components, sensors and electronic servo channels. In this paper, a simple and reliable scheme is suggested which axially stabilizes and linearly perturbs the piston so that the need for a separate motor for axial actuation can be totally dispensed with. The piston is radially supported by passive repulsive bearings. In the axial direction, a servo actuator ''balances'' the piston and also actuates it bi-directionally. Implemented of this ''bearing cum motor theme,'' reduces the number of electromechanical and electronic components required to operate the system and hence minimizes the chances of system failure. Apart from this, the system's power consumption is reduced and efficiency is improved as electrical heating losses caused by quiescent-operating currents are removed and electromagnetic losses on the moving parts are minimized. The necessary system parameters have been derived using finite element analysis techniques. Finally, the proposed design is validated by computer-aided system simulation

  17. H∞ control for uncertain linear system over networks with Bernoulli data dropout and actuator saturation.

    Science.gov (United States)

    Yu, Jimin; Yang, Chenchen; Tang, Xiaoming; Wang, Ping

    2018-03-01

    This paper investigates the H ∞ control problems for uncertain linear system over networks with random communication data dropout and actuator saturation. The random data dropout process is modeled by a Bernoulli distributed white sequence with a known conditional probability distribution and the actuator saturation is confined in a convex hull by introducing a group of auxiliary matrices. By constructing a quadratic Lyapunov function, effective conditions for the state feedback-based H ∞ controller and the observer-based H ∞ controller are proposed in the form of non-convex matrix inequalities to take the random data dropout and actuator saturation into consideration simultaneously, and the problem of non-convex feasibility is solved by applying cone complementarity linearization (CCL) procedure. Finally, two simulation examples are given to demonstrate the effectiveness of the proposed new design techniques. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  18. Design and fabrication of a micro PZT cantilever array actuator for applications in fluidic systems

    DEFF Research Database (Denmark)

    Kim, H.; In, C.; Yoon, Gil Ho

    2005-01-01

    In this article, a micro cantilever array actuated by PZT films is designed and fabricated for micro fluidic systems. The design features for maximizing tip deflections and minimizing fluid leakage are described. The governing equation of the composite PZT cantilever is derived and the actuating......, dielectric constant, and dielectric loss. Tip deflections of 12 mu m at 5 V are measured, which agreed well with the predicted value. The 18 mu l/s leakage rate of air was observed at a pressure difference of 1000 Pa. Micro cooler is introduced, and its possible application to micro compressor is discussed....

  19. Integral isolation valve systems for loss of coolant accident protection

    Science.gov (United States)

    Kanuch, David J.; DiFilipo, Paul P.

    2018-03-20

    A nuclear reactor includes a nuclear reactor core comprising fissile material disposed in a reactor pressure vessel having vessel penetrations that exclusively carry flow into the nuclear reactor and at least one vessel penetration that carries flow out of the nuclear reactor. An integral isolation valve (IIV) system includes passive IIVs each comprising a check valve built into a forged flange and not including an actuator, and one or more active IIVs each comprising an active valve built into a forged flange and including an actuator. Each vessel penetration exclusively carrying flow into the nuclear reactor is protected by a passive IIV whose forged flange is directly connected to the vessel penetration. Each vessel penetration carrying flow out of the nuclear reactor is protected by an active IIV whose forged flange is directly connected to the vessel penetration. Each active valve may be a normally closed valve.

  20. Design optimization of a novel pMDI actuator for systemic drug delivery.

    Science.gov (United States)

    Kakade, Prashant P; Versteeg, Henk K; Hargrave, Graham K; Genova, Perry; Williams Iii, Robert C; Deaton, Daniel

    2007-01-01

    Pressurized metered dose inhalers (pMDIs) are the most widely prescribed and economical respiratory drug delivery systems. Conventional pMDI actuators-those based on "two-orifice-and-sump" designs-produce an aerosol with a reasonable respirable fraction, but with high aerosol velocity. The latter is responsible for high oropharyngeal deposition, and consequently low drug delivery efficiency. Kos' pMDI technology is based on a proprietary vortex nozzle actuator (VNA), an innovative actuator configuration that seeks to reduce aerosol plume velocity, thereby promoting deep lung deposition. Using VNA development as a case study, this paper presents a systematic design optimization process to improve the actuator performance through use of advanced optical characterization tools. The optimization effort mainly relied on laser-based optical diagnostics to provide an improved understanding of the fundamentals of aerosol formation and interplay of various geometrical factors. The performance of the optimized VNA design thus evolved was characterized using phase Doppler anemometry and cascade impaction. The aerosol velocities for both standard and optimized VNA designs were found to be comparable, with both notably less than conventional actuators. The optimized VNA design also significantly reduces drug deposition in the actuator as well as USP throat adapter, which in turn, leads to a significantly higher fine particle fraction than the standard design (78 +/- 3% vs. 63 +/- 2% on an ex valve basis). This improved drug delivery efficiency makes VNA technology a practical proposition as a systemic drug delivery platform. Thus, this paper demonstrates how advanced optical diagnostic and characterization tools can be used in the development of high efficiency aerosol drug delivery devices.

  1. The run permit protection system for GTA

    International Nuclear Information System (INIS)

    Atkins, W.H.; Jones, R.G.

    1992-01-01

    A Run Permit system has been designed for the Ground Test Accelerator (GTA). The system implements mode-dependent software interlocks to ensure proper operation of the accelerator, enabling the ion source extractor and RF systems when proper conditions are met. The system is implemented using the GTA control system; thus all information available to the control system is also available for use in interlock logic. The logic is defined in terms of control system channels, which reflect accelerator parameters such as actuator positions, power supply values, temperatures, etc. A mode switch in the control room selects the accelerator operating mode, for example i njector only . The Run Permit software selects interlock logic as appropriate operating mode. This implementation easily accommodates logic changes as requirements evolve. To ensure reliable operation of a software-based system, a special circuit with a watch-dog timer is employed to produce the system's output signals. The software must periodically address the circuit, or the output signals are forced to a disabled state. For additional protection, there are self-test provisions for detecting and reacting to failures of the control system. (Author) 4 figs., ref

  2. Unbalance detection in rotor systems with active bearings using self-sensing piezoelectric actuators

    Science.gov (United States)

    Ambur, Ramakrishnan; Rinderknecht, Stephan

    2018-03-01

    Machines which are developed today are highly automated due to increased use of mechatronic systems. To ensure their reliable operation, fault detection and isolation (FDI) is an important feature along with a better control. This research work aims to achieve and integrate both these functions with minimum number of components in a mechatronic system. This article investigates a rotating machine with active bearings equipped with piezoelectric actuators. There is an inherent coupling between their electrical and mechanical properties because of which they can also be used as sensors. Mechanical deflection can be reconstructed from these self-sensing actuators from measured voltage and current signals. These virtual sensor signals are utilised to detect unbalance in a rotor system. Parameters of unbalance such as its magnitude and phase are detected by parametric estimation method in frequency domain. Unbalance location has been identified using hypothesis of localization of faults. Robustness of the estimates against outliers in measurements is improved using weighted least squares method. Unbalances are detected in a real test bench apart from simulation using its model. Experiments are performed in stationary as well as in transient case. As a further step unbalances are estimated during simultaneous actuation of actuators in closed loop with an adaptive algorithm for vibration minimisation. This strategy could be used in systems which aim for both fault detection and control action.

  3. Distributed Fault-Tolerant Control of Networked Uncertain Euler-Lagrange Systems Under Actuator Faults.

    Science.gov (United States)

    Chen, Gang; Song, Yongduan; Lewis, Frank L

    2016-05-03

    This paper investigates the distributed fault-tolerant control problem of networked Euler-Lagrange systems with actuator and communication link faults. An adaptive fault-tolerant cooperative control scheme is proposed to achieve the coordinated tracking control of networked uncertain Lagrange systems on a general directed communication topology, which contains a spanning tree with the root node being the active target system. The proposed algorithm is capable of compensating for the actuator bias fault, the partial loss of effectiveness actuation fault, the communication link fault, the model uncertainty, and the external disturbance simultaneously. The control scheme does not use any fault detection and isolation mechanism to detect, separate, and identify the actuator faults online, which largely reduces the online computation and expedites the responsiveness of the controller. To validate the effectiveness of the proposed method, a test-bed of multiple robot-arm cooperative control system is developed for real-time verification. Experiments on the networked robot-arms are conduced and the results confirm the benefits and the effectiveness of the proposed distributed fault-tolerant control algorithms.

  4. Efficient control of servo pneumatic actuator system utilizing by-pass ...

    Indian Academy of Sciences (India)

    The issue of energy saving nowadays is very crucial. Pneumatic systems, constituting an important segment of almost every industry, represent large energy consumers. Also, a significant problem with servo pneumatic actuators is achieving accuracy in positioning. The higher the positioning accuracy, the higher the ...

  5. Vibration isolation and dual-stage actuation pointing system for space precision payloads

    Science.gov (United States)

    Kong, Yongfang; Huang, Hai

    2018-02-01

    Pointing and stability requirements for future space missions are becoming more and more stringent. This work follows the pointing control method which consists of a traditional spacecraft attitude control system and a payload active pointing loop, further proposing a vibration isolation and dual-stage actuation pointing system for space precision payloads based on a soft Stewart platform. Central to the concept is using the dual-stage actuator instead of the traditional voice coil motor single-stage actuator to improve the payload active pointing capability. Based on a specified payload, the corresponding platform was designed to be installed between the spacecraft bus and the payload. The performance of the proposed system is demonstrated by preliminary closed-loop control investigations in simulations. With the ordinary spacecraft bus, the line-of-sight pointing accuracy can be controlled to below a few milliarcseconds in tip and tilt. Meanwhile, utilizing the voice coil motor with the softening spring in parallel, which is a portion of the dual-stage actuator, the system effectively achieves low-frequency motion transmission and high-frequency vibration isolation along the other four degree-of-freedom directions.

  6. Adaptive protection algorithm and system

    Science.gov (United States)

    Hedrick, Paul [Pittsburgh, PA; Toms, Helen L [Irwin, PA; Miller, Roger M [Mars, PA

    2009-04-28

    An adaptive protection algorithm and system for protecting electrical distribution systems traces the flow of power through a distribution system, assigns a value (or rank) to each circuit breaker in the system and then determines the appropriate trip set points based on the assigned rank.

  7. A smart experimental technique for the optimization of dielectric elastomer actuator (DEA) systems

    International Nuclear Information System (INIS)

    Hodgins, M; Rizzello, G; York, A; Seelecke, S; Naso, D

    2015-01-01

    In order to aid in moving dielectric elastomer actuator (DEA) technology from the laboratory into a commercial product DEA prototypes should be tested against a variety of loading conditions and eventually in the end user conditions. An experimental test setup to seamlessly perform mechanical characterization and loading of the DEA would be a great asset toward this end. Therefore, this work presents the design, control and systematic validation of a benchtop testing station for miniature silicon based circular DEAs. A versatile benchtop tester is able to characterize and apply programmable loading forces to the DEA while measuring actuator performance. The tester successfully applied mechanical loads to the DEA (including positive, constant and negative stiffness loads) simulating biasing systems via an electromagnetic linear motor operating in closed loop with a force/mechanical impedance control scheme. The tester expedites mechanical testing of the DEA by eliminating the need to build intricate pre-load mechanisms or use multiple testing jigs for characterizing the DEA response. The results show that proper mechanical loading of the DEA increases the overall electromechanical sensitivity of the system and thereby the actuator output. This approach to characterize and apply variable loading forces to DEAs in a single test system will enable faster realization of higher performance actuators. (paper)

  8. Time response for sensor sensed to actuator response for mobile robotic system

    Science.gov (United States)

    Amir, N. S.; Shafie, A. A.

    2017-11-01

    Time and performance of a mobile robot are very important in completing the tasks given to achieve its ultimate goal. Tasks may need to be done within a time constraint to ensure smooth operation of a mobile robot and can result in better performance. The main purpose of this research was to improve the performance of a mobile robot so that it can complete the tasks given within time constraint. The problem that is needed to be solved is to minimize the time interval between sensor detection and actuator response. The research objective is to analyse the real time operating system performance of sensors and actuators on one microcontroller and on two microcontroller for a mobile robot. The task for a mobile robot for this research is line following with an obstacle avoidance. Three runs will be carried out for the task and the time between the sensors senses to the actuator responses were recorded. Overall, the results show that two microcontroller system have better response time compared to the one microcontroller system. For this research, the average difference of response time is very important to improve the internal performance between the occurrence of a task, sensors detection, decision making and actuator response of a mobile robot. This research helped to develop a mobile robot with a better performance and can complete task within the time constraint.

  9. Adaptive tracking control for active suspension systems with non-ideal actuators

    Science.gov (United States)

    Pan, Huihui; Sun, Weichao; Jing, Xingjian; Gao, Huijun; Yao, Jianyong

    2017-07-01

    As a critical component of transportation vehicles, active suspension systems are instrumental in the improvement of ride comfort and maneuverability. However, practical active suspensions commonly suffer from parameter uncertainties (e.g., the variations of payload mass and suspension component parameters), external disturbances and especially the unknown non-ideal actuators (i.e., dead-zone and hysteresis nonlinearities), which always significantly deteriorate the control performance in practice. To overcome these issues, this paper synthesizes an adaptive tracking control strategy for vehicle suspension systems to achieve suspension performance improvements. The proposed control algorithm is formulated by developing a unified framework of non-ideal actuators rather than a separate way, which is a simple yet effective approach to remove the unexpected nonlinear effects. From the perspective of practical implementation, the advantages of the presented controller for active suspensions include that the assumptions on the measurable actuator outputs, the prior knowledge of nonlinear actuator parameters and the uncertain parameters within a known compact set are not required. Furthermore, the stability of the closed-loop suspension system is theoretically guaranteed by rigorous mathematical analysis. Finally, the effectiveness of the presented adaptive control scheme is confirmed using comparative numerical simulation validations.

  10. Fractional order modeling and control of dissimilar redundant actuating system used in large passenger aircraft

    Directory of Open Access Journals (Sweden)

    Salman IJAZ

    2018-05-01

    Full Text Available In this paper, a methodology has been developed to address the issue of force fighting and to achieve precise position tracking of control surface driven by two dissimilar actuators. The nonlinear dynamics of both actuators are first approximated as fractional order models. Based on the identified models, three fractional order controllers are proposed for the whole system. Two Fractional Order PID (FOPID controllers are dedicated to improving transient response and are designed in a position feedback configuration. In order to synchronize the actuator dynamics, a third fractional order PI controller is designed, which feeds the force compensation signal in position feedback loop of both actuators. Nelder-Mead (N-M optimization technique is employed in order to optimally tune controller parameters based on the proposed performance criteria. To test the proposed controllers according to real flight condition, an external disturbance of higher amplitude that acts as airload is applied directly on the control surface. In addition, a disturbance signal function of system states is applied to check the robustness of proposed controller. Simulation results on nonlinear system model validated the performance of the proposed scheme as compared to optimal PID and high gain PID controllers. Keywords: Aerospace, Fractional order control, Model identification, Nelder-Mead optimization, Robustness

  11. FIRE PROTECTION SYSTEMS AND TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    Aristov Denis Ivanovich

    2016-03-01

    Full Text Available The All-Russian Congress “Fire Stop Moscow” was de-voted to the analysis of the four segments of the industry of fire protection systems and technologies: the design of fire protec-tion systems, the latest developments and technologies of active and passive fire protection of buildings, the state and the devel-opment of the legal framework, the practice of fire protection of buildings and structures. The forum brought together the repre-sentatives of the industry of fire protection systems, scientists, leading experts, specialists in fire protection and representatives of construction companies from different regions of Russia. In parallel with the Congress Industrial Exhibition of fire protection systems, materials and technology was held, where manufacturers presented their products. The urgency of the “Fire Stop Moscow” Congress in 2015 organized by the Congress Bureau ODF Events lies primarily in the fact that it considered the full range of issues related to the fire protection of building and construction projects; studied the state of the regulatory framework for fire safety and efficiency of public services, research centers, private companies and busi-nesses in the area of fire safety. The main practical significance of the event which was widely covered in the media space, was the opportunity to share the views and information between management, science, and practice of business on implementing fire protection systems in the conditions of modern economic relations and market realities. : congress, fire protection, systems, technologies, fire protection systems, exhibition

  12. System Identification and Embedded Controller Design for Pneumatic Actuator with Stiffness Characteristic

    Directory of Open Access Journals (Sweden)

    Khairuddin Osman

    2014-01-01

    Full Text Available This paper presents model and controller design applications to pneumatic actuator embedded system. Two model strategies of position and force are proposed to realize compliance control for stiffness characteristic. Model of the pneumatic actuator system (transfer function is obtained from system identification (SI method. Next, combination of predictive functional control with observer (PFC-O design is selected as a new control strategy for pneumatic system. Performance assessment of the controller is performed in MATLAB and validated through real-time experiments using national instrument (NI devices and programmable system on chip (PSoC microcontroller. Result shows that the new controller is adapted to the system and able to successfully control both simulation and real-time experiments.

  13. Design of a Compact Actuation and Control System for Flexible Medical Robots.

    Science.gov (United States)

    Morimoto, Tania K; Hawkes, Elliot Wright; Okamura, Allison M

    2017-07-01

    Flexible medical robots can improve surgical procedures by decreasing invasiveness and increasing accessibility within the body. Using preoperative images, these robots can be designed to optimize a procedure for a particular patient. To minimize invasiveness and maximize biocompatibility, the actuation units of flexible medical robots should be placed fully outside the patient's body. In this letter, we present a novel, compact, lightweight, modular actuation, and control system for driving a class of these flexible robots, known as concentric tube robots. A key feature of the design is the use of three-dimensional printed waffle gears to enable compact control of two degrees of freedom within each module. We measure the precision and accuracy of a single actuation module and demonstrate the ability of an integrated set of three actuation modules to control six degrees of freedom. The integrated system drives a three-tube concentric tube robot to reach a final tip position that is on average less than 2 mm from a given target. In addition, we show a handheld manifestation of the device and present its potential applications.

  14. Pneumatic muscle actuated parallel asymmetrical gripper system with one mobile jaw

    Directory of Open Access Journals (Sweden)

    Deaconescu Tudor

    2017-01-01

    Full Text Available The paper pertains to the field of the current global endeavours in industrial robot construction, the presented research being oriented towards identifying innovative constructive solutions for gripper systems. The utilisation of the linear pneumatic muscle as actuator of the gripper system ensures a construction that is light, highly compliant, and that meets the safety requirements related to interaction with humans. The paper further presents and discusses such a system of asymmetrical construction with a single mobile jaw.

  15. Advanced launch system (ALS) - Electrical actuation and power systems improve operability and cost picture

    Science.gov (United States)

    Sundberg, Gale R.

    1990-01-01

    To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrrical power system and controls for all aviation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a sdpecific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military ans civilian aircraft, lunar/Martian vehicles, and a multitude of comercial applications.

  16. Bio-Inspired Control of an Arm Exoskeleton Joint with Active-Compliant Actuation System

    Directory of Open Access Journals (Sweden)

    Michele Folgheraiter

    2009-01-01

    Full Text Available This paper presents the methodology followed on the design of a multi-contact point haptic interface that uses a bio-inspired control approach and a novel actuation system. The combination of these components aims at creating a system that increases the operability of the target, and, at the same time, enables an intuitive and safe tele-operation of any complex robotic system of any given morphology. The novelty lies on the combination of a thoughtful kinematic structure driven by an active-compliant actuation system and a bio-inspired paradigm for its regulation. Due to the proposed actuation approach, the final system will achieve the condition of wearable system. On that final solution, each joint will be able to change its stiffness depending on the task to be executed, and on the anatomical features of each individual. Moreover, the system provides a variety of safety mechanisms at different levels to prevent causing any harm to the operator. In future, the system should allow the complete virtual immersion of the user within the working scenario.

  17. Remaining Useful Lifetime Prognosis of Controlled Systems: A Case of Stochastically Deteriorating Actuator

    Directory of Open Access Journals (Sweden)

    Danh Ngoc Nguyen

    2015-01-01

    Full Text Available This paper addresses the case of automatic controlled system which deteriorates during its operation because of components’ wear or deterioration. Depending on its specific closed-loop structure, the controlled system has the ability to compensate for disturbances affecting the actuators which can remain partially hidden. The deterioration modeling and the Remaining Useful Lifetime (RUL estimation for such closed-loop dynamic system have not been addressed extensively. In this paper, we consider a controlled system with Proportional-Integral-Derivative controller. It is assumed that the actuator is subject to shocks that occur randomly in time. An integrated model is proposed to jointly describe the state of the controlled process and the actuator deterioration. Only the output of the controlled system is available to assess its health condition. By considering a Piecewise Deterministic Markov Process, the RUL of the system can be estimated by a two-step approach. In the first step referred as the “Diagnosis” step, the system state is estimated online from the available monitoring observations by using a particle filtering method. In the second step referred as the “Prognosis” step, the RUL is estimated as a conditional reliability by Monte Carlo simulation. To illustrate the approach, a simulated tank level control system is used.

  18. Simplified design of the coulometric sensor-actuator system by the application of a time-dependent actuator current

    NARCIS (Netherlands)

    Olthuis, Wouter; Bergveld, Piet

    1992-01-01

    Acid or base concentrations can be determined by performing an acid-base titration with coulometrically generated OH¿ or H+ ions at a noble metal actuator electrode in close proximity to the pH-sensitive gate of an ISFET. It is shown, both theoretically and experimentally, that the relation between

  19. Extended state observer-based motion synchronisation control for hybrid actuation system of large civil aircraft

    Science.gov (United States)

    Wang, Xingjian; Shi, Cun; Wang, Shaoping

    2017-07-01

    Hybrid actuation system with dissimilar redundant actuators, which is composed of a hydraulic actuator (HA) and an electro-hydrostatic actuator (EHA), has been applied on modern civil aircraft to improve the reliability. However, the force fighting problem arises due to different dynamic performances between HA and EHA. This paper proposes an extended state observer (ESO)-based motion synchronisation control method. To cope with the problem of unavailability of the state signals, the well-designed ESO is utilised to observe the HA and EHA state variables which are unmeasured. In particular, the extended state of ESO can estimate the lumped effect of the unknown external disturbances acting on the control surface, the nonlinear dynamics, uncertainties, and the coupling term between HA and EHA. Based on the observed states of ESO, motion synchronisation controllers are presented to make HA and EHA to simultaneously track the desired motion trajectories, which are generated by a trajectory generator. Additionally, the unknown disturbances and the coupling terms can be compensated by using the extended state of the proposed ESO. Finally, comparative simulation results indicate that the proposed ESO-based motion synchronisation controller can achieve great force fighting reduction between HA and EHA.

  20. Self-Learning Variable Structure Control for a Class of Sensor-Actuator Systems

    Science.gov (United States)

    Chen, Sanfeng; Li, Shuai; Liu, Bo; Lou, Yuesheng; Liang, Yongsheng

    2012-01-01

    Variable structure strategy is widely used for the control of sensor-actuator systems modeled by Euler-Lagrange equations. However, accurate knowledge on the model structure and model parameters are often required for the control design. In this paper, we consider model-free variable structure control of a class of sensor-actuator systems, where only the online input and output of the system are available while the mathematic model of the system is unknown. The problem is formulated from an optimal control perspective and the implicit form of the control law are analytically obtained by using the principle of optimality. The control law and the optimal cost function are explicitly solved iteratively. Simulations demonstrate the effectiveness and the efficiency of the proposed method. PMID:22778633

  1. Data-based fault-tolerant control for affine nonlinear systems with actuator faults.

    Science.gov (United States)

    Xie, Chun-Hua; Yang, Guang-Hong

    2016-09-01

    This paper investigates the fault-tolerant control (FTC) problem for unknown nonlinear systems with actuator faults including stuck, outage, bias and loss of effectiveness. The upper bounds of stuck faults, bias faults and loss of effectiveness faults are unknown. A new data-based FTC scheme is proposed. It consists of the online estimations of the bounds and a state-dependent function. The estimations are adjusted online to compensate automatically the actuator faults. The state-dependent function solved by using real system data helps to stabilize the system. Furthermore, all signals in the resulting closed-loop system are uniformly bounded and the states converge asymptotically to zero. Compared with the existing results, the proposed approach is data-based. Finally, two simulation examples are provided to show the effectiveness of the proposed approach. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  2. Sensor-integrated polymer actuators for closed-loop drug delivery system

    Science.gov (United States)

    Xu, Han; Wang, Chunlei; Kulinsky, Lawrence; Zoval, Jim; Madou, Marc

    2006-03-01

    This work presents manufacturing and testing of a closed-loop drug delivery system where drug release is achieved by an electrochemical actuation of an array of polymeric valves on a set of drug reservoirs. The valves are based on bi-layer structures made of polypyrrole/gold in the shape of a flap that is hinged on one side of a valve seat. Drugs stored in the underlying chambers are released by bending the bi-layer flaps back with a small applied bias. These polymeric valves simultaneously function as both drug release components and biological/chemical sensors responding to a specific biological or environmental stimulus. The sensors may send signals to the control module to realize closed-loop control of the drug release. In this study a glucose sensor has been integrated with the polymeric actuators through immobilization of glucose oxidase(GOx) within polypyrrole(PPy) valves. Sensitivities per unit area of the integrated glucose sensor have been measured and compared before and after the actuation of the sensor/actuator PPy/DBS/GOx film. Other sensing parameters such as linear range and response time were discussed as well. Using an array of these sensor/actuator cells, the amount of released drug, e.g. insulin, can be precisely controlled according to the surrounding glucose concentration detected by the glucose sensor. Activation of these reservoirs can be triggered either by the signal from the sensor, or by the signal from the operator. This approach also serves as the initial step to use the proposed system as an implantable drug delivery platform in the future.

  3. Protection of industrial power systems

    CERN Document Server

    DAVIES, T

    2006-01-01

    The protection which is installed on an industrial power system is likely to be subjected to more difficult conditions than the protection on any other kind of power system. Starting with the many simple devices which are employed and covering the whole area of industrial power system protection, this book aims to help achieve a thorough understanding of the protection necessary.Vital aspects such as the modern cartridge fuse, types of relays, and the role of the current transformer are covered and the widely used inverse definite-minimum time overcurrent relay, the theory of the M

  4. Optical Force Sensor for the DEXMART Hand Twisted String Actuation System

    Directory of Open Access Journals (Sweden)

    Gianluca PALLI

    2013-01-01

    Full Text Available In this paper, the force sensor developed for the twisted string actuation system of the DEXMART Hand is described. The proposed solution makes use of optoelectronic components for measuring the deformation of the properly designed motor module structure caused by the force applied to the tendon transmission system. The paper reports the working principle, the calibration and the characterization of the sensor in terms of sensitivity, repeatability, full-scale and Signal-to-Noise ratio.

  5. On Energy Efficient Mobile Hydraulic Systems : with Focus on Linear Actuation

    OpenAIRE

    Heybroek, Kim

    2017-01-01

    In this dissertation, energy efficient hydraulic systems are studied. The research focuses on solutions for linear actuators in mobile applications, with emphasis on construction machines. Alongside the aspect of energy efficiency, the thesis deals with competing aspects in hydraulic system design found in the development of construction machines. Simulation models and controls for different concepts are developed, taking the whole machine into account. In line with this work, several proof o...

  6. Piezoelectrically Actuated Robotic System for MRI-Guided Prostate Percutaneous Therapy

    OpenAIRE

    Su, Hao; Shang, Weijian; Cole, Gregory; Li, Gang; Harrington, Kevin; Camilo, Alexander; Tokuda, Junichi; Tempany, Clare M.; Hata, Nobuhiko; Fischer, Gregory S.

    2014-01-01

    This paper presents a fully-actuated robotic system for percutaneous prostate therapy under continuously acquired live magnetic resonance imaging (MRI) guidance. The system is composed of modular hardware and software to support the surgical workflow of intra-operative MRI-guided surgical procedures. We present the development of a 6-degree-of-freedom (DOF) needle placement robot for transperineal prostate interventions. The robot consists of a 3-DOF needle driver module and a 3-DOF Cartesian...

  7. Reactivity Accidents in CAREM-25 Core with and Without Safety Systems Actuation

    International Nuclear Information System (INIS)

    Gimenez, Marcelo; Vertullo, Alicia; Schlamp, Miguel

    2000-01-01

    A reactivity accident in CAREM core can be provoked by different initiating events, a cold water injection in pressure vessel, a secondary side steam line breakage and a failure in the absorbing rods drive system.The present work analyses inadverted control rod withdraws transients.Maximum worth control rod (2.5 $) at normal velocity (1 cm/s) is adopted for the simulations (Reactivity ramp of 0.018 $/s).Different scenarios considering actuation of first shutdown system (FSS), second shutdown system (SSS) and selflimiting conditions were modeled.Results of the accident with actuation of FSS show that safety margins are well above critical values (DNBR and CPR).In the cases with failure of the FSS and success of SSS or selflimited, safety margins are below critical values, however, the SSS provides a reduction of elapsed time under advised margins

  8. A space release/deployment system actuated by shape memory wires

    Science.gov (United States)

    Fragnito, Marino; Vetrella and, Sergio

    2002-11-01

    In this paper, the design of an innovative hold down/release and deployment device actuated by shape memory wires, to be used for the first time for the S MA RT microsatellite solar wings is shown. The release and deployment mechanisms are actuated by a Shape Memory wire (Nitinol), which allows a complete symmetrical and synchronous release, in a very short time, of the four wings in pairs. The hold down kinematic mechanism is preloaded to avoid vibration nonlinearities and unwanted deployment at launch. The deployment mechanism is a simple pulley system. The stiffness of the deployed panel-hinge system needs to be dimensioned in order to meet the on-orbit requirement for attitude control. One-way roller clutches are used to keep the panel at the desired angle during the mission. An ad hoc software has been developed to simulate both the release and deployment operations, coupling the SMA wire behavior with the system mechanics.

  9. Optimal reliability design for over-actuated systems based on the MIT rule: Application to an octocopter helicopter testbed

    International Nuclear Information System (INIS)

    Chamseddine, Abbas; Theilliol, Didier; Sadeghzadeh, Iman; Zhang, Youmin; Weber, Philippe

    2014-01-01

    This paper addresses the problem of optimal reliability in over-actuated systems. Overloading an actuator decreases its overall lifetime and reduces its average performance over a long time. Therefore, performance and reliability are two conflicting requirements. While appropriate reliability is related to average loads, good performance is related to fast response and sufficient loads generated by actuators. Actuator redundancy allows us to address both performance and reliability at the same time by properly allocating desired loads among redundant actuators. The main contribution of this paper is the on-line optimization of the overall plant reliability according to performance objective using an MIT (Massachusetts Institute of Technology) rule-based method. The effectiveness of the proposed method is illustrated through an experimental application to an octocopter helicopter testbed

  10. Design of Servo Scheme and Drive Electronics for the Integrated Electrohydraulic Actuation System of RLV-TD

    Science.gov (United States)

    Kurian, Priya C.; Gopinath, Anish; Shinoy, K. S.; Santhi, P.; Sundaramoorthy, K.; Sebastian, Baby; Jaya, B.; Namboodiripad, M. N.; Mookiah, T.

    2017-12-01

    Reusable Launch Vehicle-Technology Demonstrator (RLV-TD) is a system which has the ability to carry a payload from the earth's surface to the outer space more than once. The control actuation forms the major component of the control system and it actuates the control surfaces of the RLV-TD based on the control commands. Eight electro hydraulic actuators were used in RLV-TD for vectoring the control surfaces about their axes. A centralised Hydraulic Power Generating Unit (HPU) was used for powering the eight actuators located in two stages. The actuation system had to work for the longest ever duration of about 850 s for an Indian launch vehicle. High bandwidth requirement from autopilot was met by the servo design using the nonlinear mathematical model. Single Control Electronics which drive four electrohydraulic actuators was developed for each stage. High power electronics with soft start scheme was realized for driving the BLDC motor which is the prime mover for hydraulic pump. Many challenges arose due to single HPU for two stages, uncertainty of aero load, higher bandwidth requirements etc. and provisions were incorporated in the design to successfully overcome them. This paper describes the servo design and control electronics architecture of control actuation system.

  11. An Analytic Model for the Success Rate of a Robotic Actuator System in Hitting Random Targets.

    Science.gov (United States)

    Bradley, Stuart

    2015-11-20

    Autonomous robotic systems are increasingly being used in a wide range of applications such as precision agriculture, medicine, and the military. These systems have common features which often includes an action by an "actuator" interacting with a target. While simulations and measurements exist for the success rate of hitting targets by some systems, there is a dearth of analytic models which can give insight into, and guidance on optimization, of new robotic systems. The present paper develops a simple model for estimation of the success rate for hitting random targets from a moving platform. The model has two main dimensionless parameters: the ratio of actuator spacing to target diameter; and the ratio of platform distance moved (between actuator "firings") to the target diameter. It is found that regions of parameter space having specified high success are described by simple equations, providing guidance on design. The role of a "cost function" is introduced which, when minimized, provides optimization of design, operating, and risk mitigation costs.

  12. Development of a hybrid safety system: Actuation of the secondary automatic depressurization system at an early stage

    International Nuclear Information System (INIS)

    Nishimoto, Masae; Umezawa, Shigemitsu; Okabe, Kazuharu; Matsuoka, Tsuyoshi

    1996-01-01

    A Hybrid Safety System, which is an optimum combination of active and passive safety systems, has been developed in order to improve the safety, reliability and economic features of the next generation of PWRs. The passive safety systems include Automatic primary Depressurization System (ADS), Secondary Automatic Depressurization System (SADS), advanced accumulators, gravity injection system and so on. In this study the authors have improved the actuation logic of the passive safety systems. The original logic in the previous study actuates ADS at an early stage of an event such as a Loss-of-Coolant Accident (LOCA), and this is followed by the actuation of SADS. In this study they divide SADS into two systems. The first, small SADS, uses small valves corresponding to the relief valves of the conventional PWR plants. The second, large SADS, corresponds to the original SADS using multiple valves of large capacity. With the new logic, the passive systems are actuated during a typical small LOCA. Small LOCA analyses using several break areas were performed for a 1,400 MWe PWR plant with a Hybrid Safety System. The results predict that core uncovery does not occur in the case of a relatively small break area and that core heat removal during a small LOCA is improved in comparison with the analyses for conventional PWR plants, where the secondary pressure remains higher during the event. The results also predict that this new logic make it possible to reduce the ADS valve size and the actuation pressure setpoint of the passive safety systems

  13. 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.

  14. Design criteria for a self-actuated shutdown system to ensure limitation of core damage

    International Nuclear Information System (INIS)

    Deane, N.A.; Atcheson, D.B.

    1981-09-01

    Safety-based functional requirements and design criteria for a self-actuated shutdown system (SASS) are derived in accordance with LOA-2 success criteria and reliability goals. The design basis transients have been defined and evaluated for the CDS Phase II design, which is a 2550 MWt mixed oxide heterogeneous core reactor. A partial set of reactor responses for selected transients is provided as a function of SASS characteristics such as reactivity worth, trip points, and insertion times

  15. Design and Implementation of Output Feedback Control for Piezo Actuated Structure Using Embedded System

    Directory of Open Access Journals (Sweden)

    R.Maheswari

    2008-06-01

    Full Text Available This paper presents the design of periodic output feedback control using state feedback gain to control the vibration of piezo actuated cantilever beam. The effectiveness of the controller is evaluated through simulation and experimentally by exciting the structure at resonance. Real time implementation of the controller is done using microcontroller. The closed loop eigen values of the system with periodic output feedback and state feedback are identical.

  16. BIOMIMETIC ACTUATION OF NON-ANTHROPOMORPHIC GRIPPER SYSTEMS

    Directory of Open Access Journals (Sweden)

    Tudor DEACONESCU

    2015-05-01

    Full Text Available The paper presents the stages of developing new, light, eco-friendly and bionic gripper systems. Gripping is achieved by means of original, self-adaptive, bio-inspired systems, with a pneumatic muscle as motion generator. The method underlying the development of these new gripping systems is based on the creation of concepts by analogy, an instrument aimed at widening the inspiration horizon in designing by using models from nature.

  17. Non-contacting actuation by radiation powered telemetry system

    International Nuclear Information System (INIS)

    Wang Xiaolin; Zhao Chunnong; Kapitola, Peter; Jacob, John; Ju Li; Blair, David G

    2004-01-01

    In laser interferometer gravitational wave detectors, local control relative to vibration isolated parts of a suspension chain may introduce noise through wires. In this paper we present a feasibility study of a wireless signal transmission method for control systems. A prototype system provides a wireless two-way signal transmission over short distances at more than 800 kbits s -1 . Wireless electric power for the system may be provided using a diode laser and solar cells with up to 33% conversion efficiency

  18. Design and Development of Autonomous High Voltage Driving System for DEAP Actuator in Radiator Thermostat

    DEFF Research Database (Denmark)

    Huang, Lina; Zhang, Zhe; Andersen, Michael A. E.

    2014-01-01

    In radiator thermostat applications, DEAP (Dielectric Electro Active Polymer) actuator tends to be a good candidate to replace the conventional self-actuating or step motor based actuator due to its intrinsic advantages. The capacitive property and high voltage (HV) driving demand of DEAP actuator...

  19. Development of a piezo-actuated micro-teleoperation system for cell manipulation.

    Science.gov (United States)

    Zareinejad, M; Rezaei, S M; Abdullah, A; Shiry Ghidary, S

    2009-03-01

    Intracytoplasmic sperm injection (ICSI) requires long training and has low success rates, primarily due to poor control over the injection force. Making force feedback available to the operator will improve the success rate of the injection task. A macro-micro-teleoperation system bridges the gap between the task performed at the micro-level and the macroscopic movements of the operator. The teleoperation slave manipulator should accurately position a needle to precisely penetrate a cell membrane. Piezoelectric actuators are widely used in micromanipulation applications; however, hysteresis non-linearity limits the accuracy of these actuators. This paper presents a novel approach for utilizing a piezoelectric nano-stage as slave manipulator of a teleoperation system. The Prandtl-Ishlinskii (PI) model is used to model actuator hysteresis in a feedforward scheme to cancel out this non-linearity. To deal with the influence of parametric uncertainties, unmodelled dynamics and PI identification error, a perturbation term is added to the slave model and applies a sliding mode-based impedance control with perturbation estimation. The stability of entire system is guaranteed by Llewellyn's absolute stability criterion. The performance of the proposed controller was investigated through experiments for cell membrane penetration. The experimental results verified the accurate position tracking in free motion and simultaneous position and force tracking in contact with a low stiffness environment.

  20. Robust Adaptive Sliding Mode Consensus of Multiagent Systems with Perturbed Communications and Actuators

    Directory of Open Access Journals (Sweden)

    Xiao-Zheng Jin

    2013-01-01

    Full Text Available This paper deals with the asymptotic consensus problem for a class of multiagent systems with time-varying additive actuator faults and perturbed communications. The L2 performance of systems is also considered in the consensus controller designs. The upper and lower bounds of faults and perturbations in actuators and communications and controller gains are assumed to be unknown but can be estimated by designing some indirect adaptive laws. Based on the information from the adaptive estimation mechanism, the distributed robust adaptive sliding mode controllers are constructed to automatically compensate for the effects of faults and perturbations and to achieve any given level of L2 gain attenuation from external disturbance to consensus errors. Through Lyapunov functions and adaptive schemes, the asymptotic consensus of resulting adaptive multiagent system can be achieved with a specified performance criterion in the presence of perturbed communications and actuators. The effectiveness of the proposed design is illustrated via a decoupled longitudinal model of F-18 aircraft.

  1. Motion control of multi-actuator hydraulic systems for mobile machineries: Recent advancements and future trends

    Science.gov (United States)

    Xu, Bing; Cheng, Min

    2018-06-01

    This paper presents a survey of recent advancements and upcoming trends in motion control technologies employed in designing multi-actuator hydraulic systems for mobile machineries. Hydraulic systems have been extensively used in mobile machineries due to their superior power density and robustness. However, motion control technologies of multi-actuator hydraulic systems have faced increasing challenges due to stringent emission regulations. In this study, an overview of the evolution of existing throttling control technologies is presented, including open-center and load sensing controls. Recent advancements in energy-saving hydraulic technologies, such as individual metering, displacement, and hybrid controls, are briefly summarized. The impact of energy-saving hydraulic technologies on dynamic performance and control solutions are also discussed. Then, the advanced operation methods of multi-actuator mobile machineries are reviewed, including coordinated and haptic controls. Finally, challenges and opportunities of advanced motion control technologies are presented by providing an overall consideration of energy efficiency, controllability, cost, reliability, and other aspects.

  2. Spatial feedforward for over-actuated flexible motion systems

    NARCIS (Netherlands)

    Ronde, M.J.C.; Schneiders, M.G.E.; Molengraft, van de M.J.G.; de Haas, D.; Steinbuch, M.; Scheidl, R.; Jakoby, B.

    2012-01-01

    In high-performance motion systems, e.g. waferstages or pick-and-place machines, there is an increasing demand for higher throughput and accuracy. The current design paradigm aims at rigid-body behaviour and leads in an evolutionary way to increasingly heavier systems that require more and more

  3. 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.

  4. SMART core protection system design

    International Nuclear Information System (INIS)

    Lee, J. K.; Park, H. Y.; Koo, I. S.; Park, H. S.; Kim, J. S.; Son, C. H.

    2003-01-01

    SMART COre Protection System(SCOPS) is designed with real-tims Digital Signal Processor(DSP) board and Network Interface Card(NIC) board. SCOPS has a Control Rod POSition (CRPOS) software module while Core Protection Calculator System(CPCS) consists of Core Protection Calculators(CPCs) and Control Element Assembly(CEA) Calculators(CEACs) in the commercial nuclear plant. It's not necessary to have a independent cabinets for SCOPS because SCOPS is physically very small. Then SCOPS is designed to share the cabinets with Plant Protection System(PPS) of SMART. Therefor it's very easy to maintain the system because CRPOS module is used instead of the computer with operating system

  5. Aircraft Dynamic Load Alleviation Using Smart Actuation System

    National Research Council Canada - National Science Library

    Appa, K

    2000-01-01

    .... This concept can also be applied to flutter suppression of any lifting surfaces. This active control algorithm can be implemented and operated independently of the primary flight control systems to avoid interference...

  6. A Solar Energy Powered Autonomous Wireless Actuator Node for Irrigation Systems

    OpenAIRE

    Lajara, Rafael; Alberola, Jorge; Pelegr?-Sebasti?, Jos?

    2010-01-01

    The design of a fully autonomous and wireless actuator node ("wEcoValve mote") based on the IEEE 802.15.4 standard is presented. The system allows remote control (open/close) of a 3-lead magnetic latch solenoid, commonly used in drip irrigation systems in applications such as agricultural areas, greenhouses, gardens, etc. The very low power consumption of the system in conjunction with the low power consumption of the valve, only when switching positions, allows the system to be solar powered...

  7. Conduction Electrohydrodynamics with Mobile Electrodes: A Novel Actuation System for Untethered Robots

    Science.gov (United States)

    Shigemune, Hiroki; Cianchetti, Matteo; Laschi, Cecilia

    2017-01-01

    Electrohydrodynamics (EHD) refers to the direct conversion of electrical energy into mechanical energy of a fluid. Through the use of mobile electrodes, this principle is exploited in a novel fashion for designing and testing a millimeter‐scale untethered robot, which is powered harvesting the energy from an external electric field. The robot is designed as an inverted sail‐boat, with the thrust generated on the sail submerged in the liquid. The diffusion constant of the robot is experimentally computed, proving that its movement is not driven by thermal fluctuations, and then its kinematic and dynamic responses are characterized for different applied voltages. The results show the feasibility of using EHD with mobile electrodes for powering untethered robots and provide new evidences for the further development of this actuation system for both mobile robots and compliant actuators in soft robotics. PMID:28932659

  8. Conduction Electrohydrodynamics with Mobile Electrodes: A Novel Actuation System for Untethered Robots.

    Science.gov (United States)

    Cacucciolo, Vito; Shigemune, Hiroki; Cianchetti, Matteo; Laschi, Cecilia; Maeda, Shingo

    2017-09-01

    Electrohydrodynamics (EHD) refers to the direct conversion of electrical energy into mechanical energy of a fluid. Through the use of mobile electrodes, this principle is exploited in a novel fashion for designing and testing a millimeter-scale untethered robot, which is powered harvesting the energy from an external electric field. The robot is designed as an inverted sail-boat, with the thrust generated on the sail submerged in the liquid. The diffusion constant of the robot is experimentally computed, proving that its movement is not driven by thermal fluctuations, and then its kinematic and dynamic responses are characterized for different applied voltages. The results show the feasibility of using EHD with mobile electrodes for powering untethered robots and provide new evidences for the further development of this actuation system for both mobile robots and compliant actuators in soft robotics.

  9. Longitudinal Absolute Stability of a BWB Aircraft-Pilot System with Saturated Actuator Model

    Directory of Open Access Journals (Sweden)

    Claudia Alice STATE

    2013-09-01

    Full Text Available This paper deals with the analysis of the P(ilot I(n-the-Loop O(scillations of the second category (with rate and position liming in the closed loop pilot-vehicle system, caused by the dynamic coupling between the human pilot and the aircraft. The analysis is made in the context of the longitudinal motion and the theoretical model of the airplane presented in this article is a (Blended(Wing (Body tailless configuration. In what concerns the human operator, this is expressed by the Synchronous Pilot Model, which is represented by a simple gain, without a specific delay. The Routh-Hurwitz criterion is used in order to analyze the longitudinal stability of the low-order pilot-airplane system without the influence of actuator nonlinearity (this means that the unsaturated actuator model is employed for the mentioned algebraic criterion. Most emphasis is put on the frequency Popov criterion, which is used to investigate the absolute stability property of the short-period model in the presence of the actuator rate saturation, in the condition of the Lurie problem. The transfer function of the longitudinal BWB model, obtained from open-loop analysis, has a double pole at the origin and, for the absolute stability feedback structure that contains the nonlinearity of the saturation type, the Popov frequency-domain inequalities are applied to the PIO II problem in this critical case.

  10. Fault-tolerant Actuator System for Electrical Steering of Vehicles

    DEFF Research Database (Denmark)

    Sørensen, Jesper Sandberg; Blanke, Mogens

    2006-01-01

    is needed that meets this requirement. This paper studies the fault-tolerance properties of an electrical steering system. It presents a fault-tolerant architecture where a dedicated AC motor design used in conjunction with cheap voltage measurements can ensure detection of all relevant faults......Being critical to the safety of vehicles, the steering system is required to maintain the vehicles ability to steer until it is brought to halt, should a fault occur. With electrical steering becoming a cost-effective candidate for electrical powered vehicles, a fault-tolerant architecture...

  11. Distributed Supervisory Protection Interlock System

    International Nuclear Information System (INIS)

    Walz, H.V.; Agostini, R.C.; Barker, L.; Cherkassky, R.; Constant, T.; Matheson, R.

    1989-03-01

    The Distributed Supervisory Protection Interlock System, DSPI, is under development at the Stanford Linear Accelerator Center for requirements in the areas of personnel protection, beam containment and equipment protection interlocks. The DSPI system, distributed over the application site, consists of segments with microprocessor-based controller and I/O modules, local area networks for communication, and a global supervisor computer. Segments are implemented with commercially available controller and I/O modules arranged in local interlock clusters, and associated software. Segments provide local interlock data acquisition, processing and control. Local area networks provide the communication backbone between segments and a global supervisor processor. The supervisor processor monitors the overall system, reports detail status and provides human interfaces. Details of an R and D test system, which will implement the requirements for personnel protection of 4 typical linear accelerator sectors, will be described. 4 refs., 2 figs

  12. Robust adaptive fault-tolerant control for leader-follower flocking of uncertain multi-agent systems with actuator failure.

    Science.gov (United States)

    Yazdani, Sahar; Haeri, Mohammad

    2017-11-01

    In this work, we study the flocking problem of multi-agent systems with uncertain dynamics subject to actuator failure and external disturbances. By considering some standard assumptions, we propose a robust adaptive fault tolerant protocol for compensating of the actuator bias fault, the partial loss of actuator effectiveness fault, the model uncertainties, and external disturbances. Under the designed protocol, velocity convergence of agents to that of virtual leader is guaranteed while the connectivity preservation of network and collision avoidance among agents are ensured as well. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  13. Structural integrated sensor and actuator systems for active flow control

    Science.gov (United States)

    Behr, Christian; Schwerter, Martin; Leester-Schädel, Monika; Wierach, Peter; Dietzel, Andreas; Sinapius, Michael

    2016-04-01

    An adaptive flow separation control system is designed and implemented as an essential part of a novel high-lift device for future aircraft. The system consists of MEMS pressure sensors to determine the flow conditions and adaptive lips to regulate the mass flow and the velocity of a wall near stream over the internally blown Coanda flap. By the oscillating lip the mass flow in the blowing slot changes dynamically, consequently the momentum exchange of the boundary layer over a high lift flap required mass flow can be reduced. These new compact and highly integrated systems provide a real-time monitoring and manipulation of the flow conditions. In this context the integration of pressure sensors into flow sensing airfoils of composite material is investigated. Mechanical and electrical properties of the integrated sensors are investigated under mechanical loads during tensile tests. The sensors contain a reference pressure chamber isolated to the ambient by a deformable membrane with integrated piezoresistors connected as a Wheatstone bridge, which outputs voltage signals depending on the ambient pressure. The composite material in which the sensors are embedded consists of 22 individual layers of unidirectional glass fiber reinforced plastic (GFRP) prepreg. The results of the experiments are used for adapting the design of the sensors and the layout of the laminate to ensure an optimized flux of force in highly loaded structures primarily for future aeronautical applications. It can be shown that the pressure sensor withstands the embedding process into fiber composites with full functional capability and predictable behavior under stress.

  14. Dissipativity-Based Reliable Control for Fuzzy Markov Jump Systems With Actuator Faults.

    Science.gov (United States)

    Tao, Jie; Lu, Renquan; Shi, Peng; Su, Hongye; Wu, Zheng-Guang

    2017-09-01

    This paper is concerned with the problem of reliable dissipative control for Takagi-Sugeno fuzzy systems with Markov jumping parameters. Considering the influence of actuator faults, a sufficient condition is developed to ensure that the resultant closed-loop system is stochastically stable and strictly ( Q, S,R )-dissipative based on a relaxed approach in which mode-dependent and fuzzy-basis-dependent Lyapunov functions are employed. Then a reliable dissipative control for fuzzy Markov jump systems is designed, with sufficient condition proposed for the existence of guaranteed stability and dissipativity controller. The effectiveness and potential of the obtained design method is verified by two simulation examples.

  15. Thermoelectric-Driven Sustainable Sensing and Actuation Systems for Fault-Tolerant Nuclear Incidents

    Energy Technology Data Exchange (ETDEWEB)

    Longtin, Jon [Stony Brook Univ., NY (United States)

    2016-02-08

    The Fukushima Daiichi nuclear incident in March 2011 represented an unprecedented stress test on the safety and backup systems of a nuclear power plant. The lack of reliable information from key components due to station blackout was a serious setback, leaving sensing, actuation, and reporting systems unable to communicate, and safety was compromised. Although there were several independent backup power sources for required safety function on site, ultimately the batteries were drained and the systems stopped working. If, however, key system components were instrumented with self-powered sensing and actuation packages that could report indefinitely on the status of the system, then critical system information could be obtained while providing core actuation and control during off-normal status for as long as needed. This research project focused on the development of such a self-powered sensing and actuation system. The electrical power is derived from intrinsic heat in the reactor components, which is both reliable and plentiful. The key concept was based around using thermoelectric generators that can be integrated directly onto key nuclear components, including pipes, pump housings, heat exchangers, reactor vessels, and shielding structures, as well as secondary-side components. Thermoelectric generators are solid-state devices capable of converting heat directly into electricity. They are commercially available technology. They are compact, have no moving parts, are silent, and have excellent reliability. The key components to the sensor package include a thermoelectric generator (TEG), microcontroller, signal processing, and a wireless radio package, environmental hardening to survive radiation, flooding, vibration, mechanical shock (explosions), corrosion, and excessive temperature. The energy harvested from the intrinsic heat of reactor components can be then made available to power sensors, provide bi-directional communication, recharge batteries for other

  16. Thermoelectric-Driven Sustainable Sensing and Actuation Systems for Fault-Tolerant Nuclear Incidents

    International Nuclear Information System (INIS)

    Longtin, Jon

    2015-09-01

    The Fukushima Daiichi nuclear incident in March 2011 represented an unprecedented stress test on the safety and backup systems of a nuclear power plant. The lack of reliable information from key components due to station blackout was a serious setback, leaving sensing, actuation, and reporting systems unable to communicate, and safety was compromised. Although there were several independent backup power sources for required safety function on site, ultimately the batteries were drained and the systems stopped working. If, however, key system components were instrumented with self-powered sensing and actuation packages that could report indefinitely on the status of the system, then critical system information could be obtained while providing core actuation and control during off-normal status for as long as needed. This research project focused on the development of such a self-powered sensing and actuation system. The electrical power is derived from intrinsic heat in the reactor components, which is both reliable and plentiful. The key concept was based around using thermoelectric generators that can be integrated directly onto key nuclear components, including pipes, pump housings, heat exchangers, reactor vessels, and shielding structures, as well as secondary-side components. Thermoelectric generators are solid-state devices capable of converting heat directly into electricity. They are commercially available technology. They are compact, have no moving parts, are silent, and have excellent reliability. The key components to the sensor package include a thermoelectric generator (TEG), microcontroller, signal processing, and a wireless radio package, environmental hardening to survive radiation, flooding, vibration, mechanical shock (explosions), corrosion, and excessive temperature. The energy harvested from the intrinsic heat of reactor components can be then made available to power sensors, provide bi-directional communication, recharge batteries for other

  17. Power system protection 3 application

    CERN Document Server

    1995-01-01

    The worldwide growth in demand for electricity has forced the pace of developments in electrical power system design to meet consumer needs for reliable, secure and cheap supplies. Power system protection, as a technology essential to high quality supply, is widely recognised as a specialism of growing and often critical importance, in which power system needs and technological progress have combined to result in rapid developments in policy and practice in recent years. In the United Kingdom, the need for appropriate training in power system protection was recognised in the early 1960s with t

  18. An innovative ultra-capacitor driven shape memory alloy actuator with an embedded control system

    International Nuclear Information System (INIS)

    Li, Peng; Song, Gangbing

    2014-01-01

    In this paper, an innovative ultra-capacitor driven shape memory alloy (SMA) actuator with an embedded control system is proposed targeting high power high-duty cycle SMA applications. The ultra-capacitor, which is capable of delivering massive amounts of instantaneous current in a compact dimension for high power applications, is chosen as the main component of the power supply. A specialized embedded system is designed from the ground up to control the ultra-capacitor driven SMA system. The control of the ultra-capacitor driven SMA is different from that of a regular constant voltage powered SMA system in that the energy and the voltage of the ultra-capacitor decrease as the system load increases. The embedded control system is also different from a computer-based control system in that it has limited computational power, and the control algorithm has to be designed to be simple while effective so that it can fit into the embedded system environment. The problem of a variable voltage power source induced by the use of the ultra-capacitor is solved by using a fuzzy PID (proportional integral and derivative) control. The method of using an ultra-capacitor to drive SMA actuators enabled SMA as a good candidate for high power high-duty cycle applications. The proposed embedded control system provides a good and ready-to-use solution for SMA high power applications. (paper)

  19. A Portable, Air-Jet-Actuator-Based Device for System Identification

    Science.gov (United States)

    Staats, Wayne; Belden, Jesse; Mazumdar, Anirban; Hunter, Ian

    2010-11-01

    System identification (ID) of human and robotic limbs could help in diagnosis of ailments and aid in optimization of control parameters and future redesigns. We present a self-contained actuator, which uses the Coanda effect to rapidly switch the direction of a high speed air jet to create a binary stochastic force input to a limb for system ID. The design of the actuator is approached with the goal of creating a portable device, which could deployed on robot or human limbs for in situ identification. The viability of the device is demonstrated by performing stochastic system ID on an underdamped elastic beam system with fixed inertia and stiffness, and variable damping. The non-parametric impulse response yielded from the stochastic system ID is modeled as a second order system, and the resultant parameters are found to be in excellent agreement with those found using more traditional system ID techniques. The current design could be further miniaturized and developed as a portable, wireless, on-site multi-axis system identification system for less intrusive and more widespread use.

  20. State and actuator fault estimation observer design integrated in a riderless bicycle stabilization system.

    Science.gov (United States)

    Brizuela Mendoza, Jorge Aurelio; Astorga Zaragoza, Carlos Manuel; Zavala Río, Arturo; Pattalochi, Leo; Canales Abarca, Francisco

    2016-03-01

    This paper deals with an observer design for Linear Parameter Varying (LPV) systems with high-order time-varying parameter dependency. The proposed design, considered as the main contribution of this paper, corresponds to an observer for the estimation of the actuator fault and the system state, considering measurement noise at the system outputs. The observer gains are computed by considering the extension of linear systems theory to polynomial LPV systems, in such a way that the observer reaches the characteristics of LPV systems. As a result, the actuator fault estimation is ready to be used in a Fault Tolerant Control scheme, where the estimated state with reduced noise should be used to generate the control law. The effectiveness of the proposed methodology has been tested using a riderless bicycle model with dependency on the translational velocity v, where the control objective corresponds to the system stabilization towards the upright position despite the variation of v along the closed-loop system trajectories. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  1. Magnetic actuators and sensors

    CERN Document Server

    Brauer, John R

    2014-01-01

    An accessible, comprehensive guide on magnetic actuators and sensors, this fully updated second edition of Magnetic Actuators and Sensors includes the latest advances, numerous worked calculations, illustrations, and real-life applications. Covering magnetics, actuators, sensors, and systems, with updates of new technologies and techniques, this exemplary learning tool emphasizes computer-aided design techniques, especially magnetic finite element analysis, commonly used by today's engineers. Detailed calculations, numerous illustrations, and discussions of discrepancies make this text an inva

  2. Electromechanical actuation of buckypaper actuator: Material properties and performance relationships

    International Nuclear Information System (INIS)

    Cottinet, P.-J.; Souders, C.; Tsai, S.-Y.; Liang, R.; Wang, B.; Zhang, C.

    2012-01-01

    Carbon nanotubes can be assembled into macroscopic thin film materials called buckypapers. To incorporate buckypaper actuators into engineering systems, it is of high importance to understand their material property-actuation performance relationships in order to model and predict the behavior of these actuators. The electromechanical actuation of macroscopic buckypaper structures and their actuators, including single and multi-walled carbon nanotube buckypapers and aligned single-walled nanotube buckypapers, were analyzed and compared. From the experimental evidence, this Letter discusses the effects of the fundamental material properties, including Young modulus and electrical double layer properties, on actuation performance of the resultant actuators. -- Highlights: ► In this study we identified the figure of merit of the electromechanical conversion. ► Different type of buckypaper was realized and characterized for actuation properties. ► The results demonstrated the potential of Buckypapers/Nafion for actuation

  3. Design of integrated systems for control and detection of actuator/sensor faults

    DEFF Research Database (Denmark)

    Stoustrup, J.; Grimble, M.J.; Niemann, Hans Henrik

    1997-01-01

    Consider control systems operating under potentially faulty conditions. Discusses the problems of designing a single unit which not only handle the required control but also identified faults occuring in actuators and sensors. In common practice, unites for control and for diagnosis are designed......-integrated design of control and diagnosis unit. Shows how a combined module for control and diagnosis can be designed which is able to follow references and reject disturbances robustly, control the system so that the undertected faults do not have disastrous effect, reduce the number of false alarams and indetify...

  4. Design Comparison of Autonomous High Voltage Driving System for DEAP Actuator

    DEFF Research Database (Denmark)

    Huang, Lina; Pittini, Riccardo; Zhang, Zhe

    2014-01-01

    As a new type of smart material, the Dielectric Electro Active Polymer (DEAP) is introduced in terms of configuration, working principle and potential applications. The design of an autonomous high voltage driving system for DEAP actuator is investigated. The system configuration and the design...... methodology of a high voltage converter are discussed in detail. Based on the heating valve application, three different high voltage converter solutions have been proposed. The different proposals have been compared in terms of energy loss, volume and cost. Finally, the design selection suggestions...

  5. Reactor protection system. Revision 1

    International Nuclear Information System (INIS)

    Fairbrother, D.B.; Vincent, D.R.; Lesniak, L.M.

    1975-04-01

    The reactor protection system-II (RPS-II) designed for use on Babcock and Wilcox 145- and 205-fuel assembly pressurized water reactors is described. In this system, relays in the trip logic have been replaced by solid state devices. A calculating module for the low DNBR, pump status, and offset trip functions has replaced the overpower trip (based on flow and imbalance), the power/RC pump trip, and the variable low pressure trip. Included is a description of the changes from the present Oconee-type reactor protection system (RPS-I), a functional and hardware description of the calculating module, and a discussion of the qualification program conducted to ensure that the degree of protection provided by RPS-II is not less than that provided by previously licensed systems supplied by B and W. (U.S.)

  6. Modern thyratron crowbar protection systems

    International Nuclear Information System (INIS)

    Judd, D.A.; Kettle, L.J.; Menown, H.; Newton, B.P.; Nicholls, N.S.; Sheldrake, R.

    1992-01-01

    Two thyratron crowbar systems for high-power klystrons used in linear accelerators are described. The first, contained in an oil filled tank, is a complete system to protect a klystron powered from a 100-kV, 20-A d.c. supply. In the second system a CX1722 glass thyratron, operating in air, has been retrofitted to a test equipment, in place of a spark gap, to protect an Inductive Output Tube (IOT). An important parameter in the choice of the crowbar thyratron is the total coulombs to be switched. Measurements of these follow-on currents are presented. (R.P.) 4 refs.; 10 figs

  7. Sandia Laboratories plutonium protection system

    International Nuclear Information System (INIS)

    Bernard, E.A.; Miyoshi, D.S.; Gutierrez, F.D.

    1977-01-01

    Sandia Laboratories is developing an improved plutonium protection system (PPS) to demonstrate new concepts for enhancing special nuclear materials safeguards. PPS concepts include separation of functions, real-time item accountability and improved means for control of materials, activities and personnel access. Physical barriers and a secure communications network are designed into the system to offer greater protection against sabotage, diversion and theft attempts. Prototype systems are being constructed at Hanford, Washington and Albuquerque, New Mexico and will be subjected to a comprehensive testing and evaluation program

  8. Standpipe systems for fire protection

    CERN Document Server

    Isman, Kenneth E

    2017-01-01

    This important new manual goes beyond the published NFPA standards on installation of standpipe systems to include the rules in the International Building Code, municipal fire codes, the National Fire Code of Canada, and information on inspection, testing, and maintenance of standpipe systems. Also covered are the interactions between standpipe and sprinkler systems, since these important fire protection systems are so frequently installed together. Illustrated with design examples and practical applications to reinforce the learning experience, this is the go-to reference for engineers, architects, design technicians, building inspectors, fire inspectors, and anyone that inspects, tests or maintains fire protection systems. Fire marshals and plan review authorities that have the responsibility for reviewing and accepting plans and hydraulic calculations for standpipe systems are also an important audience, as are firefighters who actually use standpipe systems. As a member of the committees responsible for s...

  9. Wavefront correction system based on an equilateral triangular arrangement of actuators

    International Nuclear Information System (INIS)

    Salmon, J.T.; Bergum, J.W.; Kartz, M.W.; Presta, R.W.; Swift, C.D.

    1993-02-01

    Atomic Vapor Laser Isotope Separation (AVLIS) requires the copropagation of multiple beams at different wavelengths and at average powers exceeding 1 kW. Although mirror coatings are used that absorb less than one part in 10 5 , the beams still suffer from thermally induced phase distortions, both in the dye amplifiers and in transmissive optics, such as beam combiners and vacuum windows. These aberrations are 2nd-order and 3rd-order and can reach 5 waves peak-to-valley (p-v), which causes the beam to distort and break up when propagated over large distances. The magnitude of the aberrations scales with power, with time constants on the order of 30 seconds. Previous adaptive systems that have been developed corrected these thermally induced phase distortions of both 2nd-order and 3rd-order; however, these systems had limited spatial resolution and in some cases marginal stability. The authors have developed a new adaptive optics system where both the actuators of the deformable mirror and the lenslets of the Hartmann sensor are arranged with centers at the vertices of equilateral triangles. The wavefront sensor is a video Hartmann sensor that also uses an equilateral array of lenslets. The controller hardware uses a VME bus. The design minimizes the generation of reflected wavefronts higher than first order across each lenslet for large excursions of actuators from positions where the mirror is flat and, thus maximizes the precision of the slopes measured by the Hartmann sensor. The design is also immune to the waffle mode that is present in the reconstructors of adaptive optics systems where actuators are arranged in a square array

  10. The Diamond machine protection system

    International Nuclear Information System (INIS)

    Heron, M.T.; Lay, S.; Chernousko, Y.; Hamadyk, P.; Rotolo, N.

    2012-01-01

    The Diamond Light Source Machine Protection System (MPS) manages the hazards from high power photon beams and other hazards to ensure equipment protection on the booster synchrotron and storage ring. The system has a shutdown requirement, on a beam mis-steer of under 1 msec and has to manage in excess of a thousand interlocks. This is realised using a combination of bespoke hardware and programmable logic controllers. The MPS monitors a large number of interlock signals from diagnostics instrumentation, vacuum instrumentation, photon front ends and plant monitoring subsystems. Based on logic it can then remove the source of the energy to ensure protection of equipment. Depending on requirements, interlocks are managed on a Local or a Global basis. The Global system is structured as two layers, and supports fast- and slow-response-time interlock requirements. A Global MPS module takes the interlock permits for a given interlock circuit from each of the cells of the accelerator, and, subject to all interlocks being good, produces a permit to operate the source of energy: the RF amplifier for vessel protection and the PSU for magnet protection. The Local MPS module takes fast Interlock inputs from one cell of the Storage Ring or one quadrant of the Booster. Fast interlocks are those that must drop the beam in under 400 μsec (the maximum speed of the interlock) in the event of failure. EPIC provides the user interface to the MPS system

  11. Optimal Mobile Sensing and Actuation Policies in Cyber-physical Systems

    CERN Document Server

    Tricaud, Christophe

    2012-01-01

    A successful cyber-physical system, a complex interweaving of hardware and software in direct interaction with some parts of the physical environment, relies heavily on proper identification of the, often pre-existing, physical elements. Based on information from that process, a bespoke “cyber” part of the system may then be designed for a specific purpose. Optimal Mobile Sensing and Actuation Strategies in Cyber-physical Systems focuses on distributed-parameter systems the dynamics of which can be modelled with partial differential equations. Such systems are very challenging to measure, their states being distributed throughout a spatial domain. Consequently, optimal strategies are needed and systematic approaches to the optimization of sensor locations have to be devised for parameter estimation. The text begins by reviewing the newer field of cyber-physical systems and introducing background notions of distributed parameter systems and optimal observation theory. New research opportunities are then de...

  12. Context-aware system for pre-triggering irreversible vehicle safety actuators.

    Science.gov (United States)

    Böhmländer, Dennis; Dirndorfer, Tobias; Al-Bayatti, Ali H; Brandmeier, Thomas

    2017-06-01

    New vehicle safety systems have led to a steady improvement of road safety and a reduction in the risk of suffering a major injury in vehicle accidents. A huge leap forward in the development of new vehicle safety systems are actuators that have to be activated irreversibly shortly before a collision in order to mitigate accident consequences. The triggering decision has to be based on measurements of exteroceptive sensors currently used in driver assistance systems. This paper focuses on developing a novel context-aware system designed to detect potential collisions and to trigger safety actuators even before an accident occurs. In this context, the analysis examines the information that can be collected from exteroceptive sensors (pre-crash data) to predict a certain collision and its severity to decide whether a triggering is entitled or not. A five-layer context-aware architecture is presented, that is able to collect contextual information about the vehicle environment and the actual driving state using different sensors, to perform reasoning about potential collisions, and to trigger safety functions upon that information. Accident analysis is used in a data model to represent uncertain knowledge and to perform reasoning. A simulation concept based on real accident data is introduced to evaluate the presented system concept. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Development of body weight support gait training system using pneumatic Mckibben actuators -control of lower extremity orthosis.

    Science.gov (United States)

    Mat Dzahir, M A; Nobutomo, T; Yamamoto, S I

    2013-01-01

    Recently, robot assisted therapy devices are increasingly used for spinal cord injury (SCI) rehabilitation in assisting handicapped patients to regain their impaired movements. Assistive robotic systems may not be able to cure or fully compensate impairments, but it should be able to assist certain impaired functions and ease movements. In this study, the control system of lower extremity orthosis for the body weight support gait training system which implements pneumatic artificial muscle (PAM) is proposed. The hip and knee joint angles of the gait orthosis system are controlled based on the PAM coordinates information from the simulation. This information provides the contraction data for the mono- and bi-articular PAMs that are arranged as posterior and anterior actuators to simulate the human walking motion. The proposed control system estimates the actuators' contraction as a function of hip and knee joint angles. Based on the contraction model obtained, input pressures for each actuators are measured. The control system are performed at different gait cycles and two PMA settings for the mono- and bi-articular actuators are evaluated in this research. The results showed that the system was able to achieve the maximum muscle moment at the joints, and able to perform the heel contact movement. This explained that the antagonistic mono- and bi-articular actuators worked effectively.

  14. Multi-level virtual prototyping of electromechanical actuation system for more electric aircraft

    Directory of Open Access Journals (Sweden)

    Jian FU

    2018-05-01

    Full Text Available Electromechanical actuators (EMAs are becoming increasingly attractive in the field of more electric aircraft because of their outstanding benefits, which include reduced fuel burn and maintenance cost, enhanced system flexibility, and improved management of fault detection and isolation. However, electromechanical actuation raises specific issues when being used for safety-critical aerospace applications like flight controls: huge reflected inertia to load, jamming-type failure, and increase of backlash with service due to wear and local dissipation of heat losses for thermal balance. This study proposes an incremental approach for virtual prototyping of EMAs. It is driven by a model-based system engineering process in order to enable simulation-aided design. Best practices supported by Bond graph formalism are suggested to develop a model’s structure efficiently and to make the model ready for use (or extension by addressing the above mentioned issues. Physical effects are progressively introduced, and the realism of lumped-parameter models is increased step-by-step. In particular, multi-level component models are architected to ensure continuity between engineering activities. The models are implemented in the AMESim simulation environment, and simulation responses are given to illustrate how they can be used for preliminary sizing, control design, thermal balance verification, and faults to failure analysis. The proposed best practices intend to provide engineers with fast, reusable, and efficient means to assess performance virtually and enhance maturity, performance, and robustness. Keywords: Bond graph, Electromechanical actuator, Flight control, Model-based system engineering, More electric aircraft, Power-by-wire

  15. Controls and Machine Protection Systems

    CERN Document Server

    Carrone, E.

    2016-01-01

    Machine protection, as part of accelerator control systems, can be managed with a 'functional safety' approach, which takes into account product life cycle, processes, quality, industrial standards and cybersafety. This paper will discuss strategies to manage such complexity and the related risks, with particular attention to fail-safe design and safety integrity levels, software and hardware standards, testing, and verification philosophy. It will also discuss an implementation of a machine protection system at the SLAC National Accelerator Laboratory's Linac Coherent Light Source (LCLS).

  16. Homotopy Analysis Method for Nonlinear Dynamical System of an Electrostatically Actuated Microcantilever

    Directory of Open Access Journals (Sweden)

    Y. M. Chen

    2011-01-01

    Full Text Available The homotopy analysis method (HAM is employed to propose an approach for solving the nonlinear dynamical system of an electrostatically actuated micro-cantilever in MEMS. There are two relative merits of the presented HAM compared with some usual procedures of the HAM. First, a new auxiliary linear operator is constructed. This operator makes it unnecessary to eliminate any secular terms. Furthermore, all the deformation equations are purely linear. Numerical examples show the excellent agreement of the attained solutions with numerical ones. The respective effects of applied voltage, cubic nonlinear stiffness, gap distance, and squeeze film damping on vibration responses are analyzed detailedly.

  17. Electrical actuators in asset management systems; Elektrische Stellantriebe in Asset-Management-Systemen

    Energy Technology Data Exchange (ETDEWEB)

    Herbstritt, Michael [AUMA Riester GmbH und Co. KG, Muellheim (Germany)

    2010-06-15

    The terms ''asset management'' and ''life-cycle management'' are nowadays popularly used to designate modern plant management. In the case of complex systems such as process-engineering plants, time and effort are necessary before an idea can be translated into data clear to all the persons involved, however. A key role is played in this context by NAMUR. This article discusses the potential benefits of asset management for electrical actuators and similar field devices and the part played by the NAMUR recommendations. (orig.)

  18. INTERDISCIPLINARY FORMATION TO ACTUATION AT UNIFIED HEALTH SYSTEM: OVERVIEW OF ARTICLES PUBLISHED IN BRAZIL

    Directory of Open Access Journals (Sweden)

    Iane Franceschet de Sousa

    2012-10-01

    Full Text Available The purpose of this study was analysed the articles published in Brazil about interdisciplinarity in the formation process in graduation level of the health profissionals for their actuation at Unified Health System. It was selected 40 publications that was conformable according to inclusion criterious. It was datached some aspects that contribute with the reflections around the subject, as the obstacles and difficulties for the interdisciplinary practice, as well the alternatives and suggestions to introduce the interdisciplinary. The most of the articles was a theoretical base, there are scarcity of practice studies that reveal effectives interdisciplinaries experiences in the formation of health profissionals.

  19. Pulse mode actuation-readout system based on MEMS resonator for liquid sensing

    DEFF Research Database (Denmark)

    Tang, Meng; Cagliani, Alberto; Davis, Zachary James

    2014-01-01

    A MEMS (Micro-Electro-Mechanical Systems) bulk disk resonator is applied for mass sensing under its dynamic mode. The classical readout circuitry involves sophisticated feedback loop and feedthrough compensation. We propose a simple straightforward non-loop pulse mode actuation and capacitive...... readout scheme. In order to verify its feasibility in liquid bio-chemical sensing environment, an experimental measurement is conducted with humidity sensing application. The measured resonant frequency changes 60kHz of 67.7MHz with a humidity change of 0~80%....

  20. Development of self-actuated shutdown system using curie point electromagnet

    International Nuclear Information System (INIS)

    Kim, Tae Ryong; Park, Jin Ho

    1999-01-01

    An innovative concept for a passive reactor shutdown system, so called self-actuated shutdown system (SASS), is inevitably required for the inherent safety in liquid metal reactor, which is designed with the totally different concept from the usual reactor shutdown system in LWR. SASS using Curie point electromagnet (CPEM) was selected as the passive reactor shutdown system for KALIMER (Korea Advanced Liquid Metal Reactor). A mock-up of the SASS was designed, fabricated and tested. From the test it was confirmed that the mockup was self-actuated at the Curie point of the temperature sensing material used in the mockup. An articulated control rod was also fabricated and assembled with the CPEM to confirm that the control rod can be inserted into core even when the control rod guide tube is deformed due to earthquake. The operability of SASS in the actual sodium environment should be confirmed in the future. All the design and test data will be applied to the KALIMER design. (author)

  1. Improved control of distributed parameter systems using wireless sensor and actuator networks: An observer-based method

    International Nuclear Information System (INIS)

    Jiang Zheng-Xian; Cui Bao-Tong; Lou Xu-Yang; Zhuang Bo

    2017-01-01

    In this paper, the control problem of distributed parameter systems is investigated by using wireless sensor and actuator networks with the observer-based method. Firstly, a centralized observer which makes use of the measurement information provided by the fixed sensors is designed to estimate the distributed parameter systems. The mobile agents, each of which is affixed with a controller and an actuator, can provide the observer-based control for the target systems. By using Lyapunov stability arguments, the stability for the estimation error system and distributed parameter control system is proved, meanwhile a guidance scheme for each mobile actuator is provided to improve the control performance. A numerical example is finally used to demonstrate the effectiveness and the advantages of the proposed approaches. (paper)

  2. Stability region of closed-loop pilot-vehicle system for fly-by-wire aircraft with limited actuator rate

    OpenAIRE

    Ying-hui, Li; Liang, Qu; Hao-jun, Xu; Qi-meng, Cao

    2017-01-01

    The category-II PIO (Pilot Induced Oscillations) caused by actuator rate limitation of fly-by-wire airplanes will badly threaten the flight safety. The stability regions of closed-loop pilot-vehicle (CLPV) system with rate limited actuator were studied in this paper to assess stability of such CLPV system. The augmented state  variables were introduced to segregate the rate limited element from the primary  system in order to build the saturation nonlinear model of CLPV system. To get the max...

  3. FAULT-TOLERANT DESIGN FOR ADVANCED DIVERSE PROTECTION SYSTEM

    Directory of Open Access Journals (Sweden)

    YANG GYUN OH

    2013-11-01

    Full Text Available For the improvement of APR1400 Diverse Protection System (DPS design, the Advanced DPS (ADPS has recently been developed to enhance the fault tolerance capability of the system. Major fault masking features of the ADPS compared with the APR1400 DPS are the changes to the channel configuration and reactor trip actuation equipment. To minimize the fault occurrences within the ADPS, and to mitigate the consequences of common-cause failures (CCF within the safety I&C systems, several fault avoidance design features have been applied in the ADPS. The fault avoidance design features include the changes to the system software classification, communication methods, equipment platform, MMI equipment, etc. In addition, the fault detection, location, containment, and recovery processes have been incorporated in the ADPS design. Therefore, it is expected that the ADPS can provide an enhanced fault tolerance capability against the possible faults within the system and its input/output equipment, and the CCF of safety systems.

  4. Design of feedback control systems for unstable plants with saturating actuators

    Science.gov (United States)

    Kapasouris, Petros; Athans, Michael; Stein, Gunter

    1988-01-01

    A new control design methodology is introduced for multi-input/multi-output systems with unstable open loop plants and saturating actuators. A control system is designed using well known linear control theory techniques and then a reference prefilter is introduced so that when the references are sufficiently small, the control system operates linearly as designated. For signals large enough to cause saturations, the control law is modified in such a way to ensure stability and to preserve, to the extent possible, the behavior of the linear control design. Key benefits of this methodology are: the modified feedback system never produces saturating control signals, integrators and/or slow dynamics in the compensator never windup, the directionaL properties of the controls are maintained, and the closed loop system has certain guaranteed stability properties. The advantages of the new design methodology are illustrated in the simulation of an approximation of the AFTI-16 (Advanced Fighter Technology Integration) aircraft multivariable longitudinal dynamics.

  5. Wireless patient monitoring system for a moving-actuator type artificial heart.

    Science.gov (United States)

    Nam, K W; Chung, J; Choi, S W; Sun, K; Min, B G

    2006-10-01

    In this study, we developed a wireless monitoring system for outpatients equipped with a moving-actuator type pulsatile bi-ventricular assist device, AnyHeart. The developed monitoring system consists of two parts; a Bluetooth-based short-distance self-monitoring system that can monitor and control the operating status of a VAD using a Bluetooth-embedded personal digital assistant or a personal computer within a distance of 10 meters, and a cellular network-based remote monitoring system that can continuously monitor and control the operating status of AnyHeart at any location. Results of in vitro experiments demonstrate the developed system's ability to monitor the operational status of an implanted AnyHeart.

  6. Dynamic Characteristics of a Hydraulic Amplification Mechanism for Large Displacement Actuators Systems

    Directory of Open Access Journals (Sweden)

    Xavier Arouette

    2010-03-01

    Full Text Available We have developed a hydraulic displacement amplification mechanism (HDAM and studied its dynamic response when combined with a piezoelectric actuator. The HDAM consists of an incompressible fluid sealed in a microcavity by two largely deformable polydimethylsiloxane (PDMS membranes. The geometry with input and output surfaces having different cross-sectional areas creates amplification. By combining the HDAM with micro-actuators, we can amplify the input displacement generated by the actuators, which is useful for applications requiring large deformation, such as tactile displays. We achieved a mechanism offering up to 18-fold displacement amplification for static actuation and 12-fold for 55 Hz dynamic actuation.

  7. Power system protection 2 systems and methods

    CERN Document Server

    1995-01-01

    The worldwide growth in demand for electricity has forced the pace of developments in electrical power system design to meet consumer needs for reliable, secure and cheap supplies. Power system protection, as a technology essential to high quality supply, is widely recognised as a specialism of growing and often critical importance, in which power system needs and technological progress have combined to result in rapid developments in policy and practice in recent years. In the United Kingdom, the need for appropriate training in power system protection was recognised in the early 1960s with t

  8. Neural network-based robust actuator fault diagnosis for a non-linear multi-tank system.

    Science.gov (United States)

    Mrugalski, Marcin; Luzar, Marcel; Pazera, Marcin; Witczak, Marcin; Aubrun, Christophe

    2016-03-01

    The paper is devoted to the problem of the robust actuator fault diagnosis of the dynamic non-linear systems. In the proposed method, it is assumed that the diagnosed system can be modelled by the recurrent neural network, which can be transformed into the linear parameter varying form. Such a system description allows developing the designing scheme of the robust unknown input observer within H∞ framework for a class of non-linear systems. The proposed approach is designed in such a way that a prescribed disturbance attenuation level is achieved with respect to the actuator fault estimation error, while guaranteeing the convergence of the observer. The application of the robust unknown input observer enables actuator fault estimation, which allows applying the developed approach to the fault tolerant control tasks. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  9. Simulation model of an electrohydraulic-actuated double-clutch transmission vehicle: modelling and system design

    Science.gov (United States)

    Schoeftner, J.; Ebner, W.

    2017-12-01

    Automated and manual transmissions are the main link between engine and powertrain. The technical term when the transmission provides the desired torque during all possible driving conditions is denoted as powertrain matching. Recent developments in the last years show that double-clutch-transmissions (DCTs) are a reasonable compromise in terms of production costs, shifting quality, drivability and fuel efficiency. They have several advantages compared to other automatic transmissions (AT). Most DCTs nowadays consist of a hydraulic actuation control unit, which controls the clutches of the gearbox in order to induce a desired drivetrain torque into the driveline. The main functions of hydraulic systems are manifold: they initiate gear shifts, they provide sufficient oil for lubrication and they control the shift quality by suitably providing a desired oil flow or pressure for the clutch actuation. In this paper, a mathematical model of a passenger car equipped with a DCT is presented. The objective of this contribution is to get an increased understanding for the dynamics of the hydraulic circuit and its coupling to the vehicle drivetrain. The simulation model consists of a hydraulic and a mechanical domain: the hydraulic actuation circuit is described by nonlinear differential equations and includes the dynamics of the line pressure and the proportional valve, as well as the influence of the pressure reducing valve, pipe resistances and accumulator dynamics. The drivetrain with its gear ratios, moments of inertia, torsional stiffness of the rotating shafts and a simple longitudinal vehicle model represent the mechanical domain. The link between hydraulic and mechanical domain is given by the clutch, which combines hydraulic equations and Newton's laws. The presented mathematical model may not only be used as a simulation model for developing the transmission control software, it may also serve as a virtual layout for the design process phase. At the end of this

  10. The LHC quench protection system

    CERN Multimedia

    2009-01-01

    The new quench protection system (QPS) has the crucial roles of providing an early warning for any part of the superconducting coils and busbars that develop high resistance, as well as triggering the switch-off of the machine. Over 2000 new detectors will be installed around the LHC to make sure every busbar segment between magnets is monitored and protected. One of the major consolidation activities for the LHC is the addition of two new detectors to the quench protection system. A magnet quench occurs when part of the superconducting cable becomes normally-conducting. When the protection system detects an increased resistance the huge amount of energy stored in the magnet chains is safely extracted and ‘dumped’ into specially designed resistors. In the case of the main dipole chain, the stored energy in a single LHC sector is roughly the same as the kinetic energy of a passenger jet at cruising speed. The first new detector is designed to monitor the superconducting...

  11. Early short-term management of control-actuator failures in a linear dynamic system

    International Nuclear Information System (INIS)

    Ben-Haim, Y.

    1989-01-01

    Early short-term management of malfunction attempts to maintain system stability during the early development stages of a failure. This is achieved in two stages. First, the failure is partially diagnosed by comparing observed system behavior against the performance expected for each of the selected set of hypothesized malfunctions. Second, the normal controller is replaced by a compensatory controller whose aim is to maintain system stability while compensating for the failure. Malfunctions involving control actuators are studied here. The aim of this study is to develop a technique for choosing the set of hypothesized failures and compensatory controllers which assure that the state of the system remains within specified bounds for a given duration after initiation of failure, regardless of the precise temporal development of the failure

  12. Active Complementary Control for Affine Nonlinear Control Systems With Actuator Faults.

    Science.gov (United States)

    Fan, Quan-Yong; Yang, Guang-Hong

    2017-11-01

    This paper is concerned with the problem of active complementary control design for affine nonlinear control systems with actuator faults. The outage and loss of effectiveness fault cases are considered. In order to achieve the performance enhancement of the faulty control system, the complementary control scheme is designed in two steps. Firstly, a novel fault estimation scheme is developed. Then, by using the fault estimations to reconstruct the faulty system dynamics and introducing a cost function as the optimization objective, a nearly optimal complementary control is obtained online based on the adaptive dynamic programming (ADP) method. Unlike most of the previous ADP methods with the addition of a probing signal, new adaptive weight update laws are derived to guarantee the convergence of neural network weights and the stability of the closed-loop system, which strongly supports the online implementation of the ADP method. Finally, two simulation examples are given to illustrate the performance and effectiveness of the proposed method.

  13. Development of a flexible microfluidic system integrating magnetic micro-actuators for trapping biological species

    International Nuclear Information System (INIS)

    Fulcrand, R; Jugieu, D; Escriba, C; Bancaud, A; Bourrier, D; Boukabache, A; Gué, A M

    2009-01-01

    A flexible microfluidic system embedding microelectromagnets has been designed, modeled and fabricated by using a photosensitive resin as structural material. The fabrication process involves the integration of micro-coils in a multilayer SU-8 microfluidic system by combining standard electroplating and dry films lamination. This technique offers numerous advantages in terms of integration, biocompatibility and chemical resistance. Various designs of micro-coils, including spiral, square or serpentine wires, have been simulated and experimentally tested. It has been established that thermal dissipation in micro-coils depends strongly on the number of turns and current density but remains compatible with biological applications. Real-time experimentations show that these micro-actuators are efficient in trapping magnetic micro-beads without any external field source or a permanent magnet and highlight that the size of microfluidic channels has been adequately designed for optimal trapping. Moreover, we trap magnetic beads in less than 2 s and release them instantaneously into the micro-channel. The actuation solely relies on electric fields, which are easier to control than standard magneto-fluidic modules

  14. Development of a flexible microfluidic system integrating magnetic micro-actuators for trapping biological species

    Science.gov (United States)

    Fulcrand, R.; Jugieu, D.; Escriba, C.; Bancaud, A.; Bourrier, D.; Boukabache, A.; Gué, A. M.

    2009-10-01

    A flexible microfluidic system embedding microelectromagnets has been designed, modeled and fabricated by using a photosensitive resin as structural material. The fabrication process involves the integration of micro-coils in a multilayer SU-8 microfluidic system by combining standard electroplating and dry films lamination. This technique offers numerous advantages in terms of integration, biocompatibility and chemical resistance. Various designs of micro-coils, including spiral, square or serpentine wires, have been simulated and experimentally tested. It has been established that thermal dissipation in micro-coils depends strongly on the number of turns and current density but remains compatible with biological applications. Real-time experimentations show that these micro-actuators are efficient in trapping magnetic micro-beads without any external field source or a permanent magnet and highlight that the size of microfluidic channels has been adequately designed for optimal trapping. Moreover, we trap magnetic beads in less than 2 s and release them instantaneously into the micro-channel. The actuation solely relies on electric fields, which are easier to control than standard magneto-fluidic modules.

  15. A system identification approach to the characterization and control of a piezoelectric tube actuator

    International Nuclear Information System (INIS)

    Mohammadzaheri, Morteza; Grainger, Steven; Bazghaleh, Mohsen

    2013-01-01

    This paper addresses the sensorless control of piezoelectric tube actuators to avoid the expense and practical limits of displacement sensors in nanopositioning applications. Three electrical signals have traditionally been used to estimate displacement: the piezoelectric voltage, the voltage induced in sensing electrodes and the voltage across a sensing resistor. In this work, the piezoelectric voltage was employed to estimate displacement; the use of this signal does not necessitate drift removal like the sensing voltage, and its superiority over the induced voltage is shown in this paper. The piezoelectric voltage is the actuating signal, so a feedforward architecture based on an inverse model is used for sensorless control. Inspired by internal model control (IMC), a filter together with the inverted model of the system, derived using system identification techniques, was used as the feedforward controller. The fixed-slope-input effect is illustrated as a prominent source of control error in tracking triangular references, then an additional nonlinear control command is proposed to address this effect and improve the control performance. (paper)

  16. Smart Control of Multiple Evaporator Systems with Wireless Sensor and Actuator Networks

    Directory of Open Access Journals (Sweden)

    Apolinar González-Potes

    2016-02-01

    Full Text Available This paper describes the complete integration of a fuzzy control of multiple evaporator systems with the IEEE 802.15.4 standard, in which we study several important aspects for this kind of system, like a detailed analysis of the end-to-end real-time flows over wireless sensor and actuator networks (WSAN, a real-time kernel with an earliest deadline first (EDF scheduler, periodic and aperiodic tasking models for the nodes, lightweight and flexible compensation-based control algorithms for WSAN that exhibit packet dropouts, an event-triggered sampling scheme and design methodologies. We address the control problem of the multi-evaporators with the presence of uncertainties, which was tackled through a wireless fuzzy control approach, showing the advantages of this concept where it can easily perform the optimization for a set of multiple evaporators controlled by the same smart controller, which should have an intelligent and flexible architecture based on multi-agent systems (MAS that allows one to add or remove new evaporators online, without the need for reconfiguring, while maintaining temporal and functional restrictions in the system. We show clearly how we can get a greater scalability, the self-configuration of the network and the least overhead with a non-beacon or unslotted mode of the IEEE 802.15.4 protocol, as well as wireless communications and distributed architectures, which could be extremely helpful in the development process of networked control systems in large spatially-distributed plants, which involve many sensors and actuators. For this purpose, a fuzzy scheme is used to control a set of parallel evaporator air-conditioning systems, with temperature and relative humidity control as a multi-input and multi-output closed loop system; in addition, a general architecture is presented, which implements multiple control loops closed over a communication network, integrating the analysis and validation method for multi

  17. Indirect adaptive fuzzy fault-tolerant tracking control for MIMO nonlinear systems with actuator and sensor failures.

    Science.gov (United States)

    Bounemeur, Abdelhamid; Chemachema, Mohamed; Essounbouli, Najib

    2018-05-10

    In this paper, an active fuzzy fault tolerant tracking control (AFFTTC) scheme is developed for a class of multi-input multi-output (MIMO) unknown nonlinear systems in the presence of unknown actuator faults, sensor failures and external disturbance. The developed control scheme deals with four kinds of faults for both sensors and actuators. The bias, drift, and loss of accuracy additive faults are considered along with the loss of effectiveness multiplicative fault. A fuzzy adaptive controller based on back-stepping design is developed to deal with actuator failures and unknown system dynamics. However, an additional robust control term is added to deal with sensor faults, approximation errors, and external disturbances. Lyapunov theory is used to prove the stability of the closed loop system. Numerical simulations on a quadrotor are presented to show the effectiveness of the proposed approach. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  18. High-temperature gas-cooled reactor steam-cycle/cogeneration lead plant. Plant Protection and Instrumentation System design description

    International Nuclear Information System (INIS)

    1983-01-01

    The Plant Protection and Instrumentation System provides plant safety system sense and command features, actuation of plant safety system execute features, preventive features which maintain safety system integrity, and safety-related instrumentation which monitors the plant and its safety systems. The primary function of the Plant Protection and Instrumentation system is to sense plant process variables to detect abnormal plant conditions and to provide input to actuation devices directly controlling equipment required to mitigate the consequences of design basis events to protect the public health and safety. The secondary functions of the Plant Protection and Instrumentation System are to provide plant preventive features, sybsystems that monitor plant safety systems status, subsystems that monitor the plant under normal operating and accident conditions, safety-related controls which allow control of reactor shutdown and cooling from a remote shutdown area

  19. Creep-Fatigue Relationsihps in Electroactive Polymer Systems and Predicted Effects in an Actuator Design

    Science.gov (United States)

    Vinogradov, Aleksandra M.; Ihlefeld, Curtis M.; Henslee, Issac

    2009-01-01

    The paper concerns the time-dependent behavior of electroactive polymers (EAP) and their use in advanced intelligent structures for space exploration. Innovative actuator design for low weight and low power valves required in small plants planned for use on the moon for chemical analysis is discussed. It is shown that in-depth understanding of cyclic loading effects observed through accelerated creep rates due to creep-fatigue interaction in polymers is critical in terms of proper functioning of EAP based actuator devices. In the paper, an overview of experimental results concerning the creep properties and cyclic creep response of a thin film piezoelectric polymer polyvinylidene fluoride (PVDF) is presented. The development of a constitutive creep-fatigue interaction model to predict the durability and service life of electroactive polymers is discussed. A novel method is proposed to predict damage accumulation and fatigue life of polymers under oyclic loading conditions in the presence of creep. The study provides a basis for ongoing research initiatives at the NASA Kennedy Space Center in the pursuit of new technologies using EAP as active elements for lunar exploration systems.

  20. Crane system with remote actuation mechanism for use in argon compartment in ACPF hot cell

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Kwang, E-mail: leejk@kaeri.re.kr; Park, Byung-Suk; Yu, Seung-Nam; Kim, Kiho; Cho, Il-je

    2016-10-15

    Highlights: • Novel crane system with a remote actuation mechanism for feasible maintenance under limited space conditions is proposed. • Linear drive systems are implemented for accurate positioning. • Modular design concepts for easy maintenance are introduced. • The motion controller and the off-the-shelf camera controller are integrated to provide more efficient operation. - Abstract: The Advanced spent fuel Conditioning Process Facility (ACPF) at the Korea Atomic Energy Research Institute (KAERI) has recently been successfully renovated. One of the highlights of this renovation project was the installation of a small argon compartment within the atmospheric hot cell of the facility. Even though a crane system was considered necessary for the remote handling of the processing equipment inside the argon compartment, no suitable commercial cranes were available. This was because a limited amount of space had been reserved for the installation of the crane. Moreover, a master-slave manipulator (MSM), the only available means of maintenance of the crane, was unable to reach it in the limited workspace. To address the difficulties in the design of this crane, in this study, a remote actuation mechanism is devised where the mechanical and electrical parts of the crane system are separated, positioned far away from each other, and connected through power transmission shafts. This approach has two main advantages. First, the electrical parts can be placed inside the workspace of the MSM, hence allowing for remote maintenance. Second, the space occupied by the electrical parts and their cables, which are separate from the crane in the proposed design, can be considered and exploited in designing the mechanical parts of the crane. This enables the construction of a short, special crane in order to maximize the workspace. Furthermore, the mechanical parts for the MSM located outside the workspace are designed to possess a high safety margin to ensure durability

  1. Design of an Active Bumper with a Series Elastic Actuator for Pedestrian Protection of Small Unmanned Vehicles

    Science.gov (United States)

    Terumasa, Narukawa; Tomoki, Tsuge; Hiroshi, Yamamoto; Takahiro, Suzuki

    2016-09-01

    When autonomous unmanned vehicles are operated on sidewalks, the vehicles must have high safety standards such as avoiding injury when they come in contact with pedestrians. In this study, we established a design for preventing serious injury when such collisions occur. We designed an active bumper with a series elastic actuator, with the goal of avoiding serious injury to a pedestrian in a collision with a small unmanned vehicle. The series elastic actuator comprised an elastic element in series with a table driven by a ball screw and servo motor. The active bumper was used to control the contact force between a vehicle and a pedestrian. The optimal force for minimizing the deflection of the object of the collision was derived, and the actuator controlled to apply this optimal force. Numerical simulations showed that the active bumper was successful in improving the collision safety of small unmanned vehicles.

  2. Large thermal protection system panel

    Science.gov (United States)

    Weinberg, David J. (Inventor); Myers, Franklin K. (Inventor); Tran, Tu T. (Inventor)

    2003-01-01

    A protective panel for a reusable launch vehicle provides enhanced moisture protection, simplified maintenance, and increased temperature resistance. The protective panel includes an outer ceramic matrix composite (CMC) panel, and an insulative bag assembly coupled to the outer CMC panel for isolating the launch vehicle from elevated temperatures and moisture. A standoff attachment system attaches the outer CMC panel and the bag assembly to the primary structure of the launch vehicle. The insulative bag assembly includes a foil bag having a first opening shrink fitted to the outer CMC panel such that the first opening and the outer CMC panel form a water tight seal at temperatures below a desired temperature threshold. Fibrous insulation is contained within the foil bag for protecting the launch vehicle from elevated temperatures. The insulative bag assembly further includes a back panel coupled to a second opening of the foil bag such that the fibrous insulation is encapsulated by the back panel, the foil bag, and the outer CMC panel. The use of a CMC material for the outer panel in conjunction with the insulative bag assembly eliminates the need for waterproofing processes, and ultimately allows for more efficient reentry profiles.

  3. Fault-tolerant Control of Discrete-time LPV systems using Virtual Actuators and Sensors

    DEFF Research Database (Denmark)

    Tabatabaeipour, Mojtaba; Stoustrup, Jakob; Bak, Thomas

    2015-01-01

    This paper proposes a new fault-tolerant control (FTC) method for discrete-time linear parameter varying (LPV) systems using a reconfiguration block. The basic idea of the method is to achieve the FTC goal without re-designing the nominal controller by inserting a reconfiguration block between......, it transforms the output of the controller for the faulty system such that the stability and performance goals are preserved. Input-to-state stabilizing LPV gains of the virtual actuator and sensor are obtained by solving linear matrix inequalities (LMIs). We show that separate design of these gains guarantees....... Finally, the effectiveness of the method is demonstrated via a numerical example and stator current control of an induction motor....

  4. Teleoperation System with Hybrid Pneumatic-Piezoelectric Actuation for MRI-Guided Needle Insertion with Haptic Feedback.

    Science.gov (United States)

    Shang, Weijian; Su, Hao; Li, Gang; Fischer, Gregory S

    2013-01-01

    This paper presents a surgical master-slave tele-operation system for percutaneous interventional procedures under continuous magnetic resonance imaging (MRI) guidance. This system consists of a piezoelectrically actuated slave robot for needle placement with integrated fiber optic force sensor utilizing Fabry-Perot interferometry (FPI) sensing principle. The sensor flexure is optimized and embedded to the slave robot for measuring needle insertion force. A novel, compact opto-mechanical FPI sensor interface is integrated into an MRI robot control system. By leveraging the complementary features of pneumatic and piezoelectric actuation, a pneumatically actuated haptic master robot is also developed to render force associated with needle placement interventions to the clinician. An aluminum load cell is implemented and calibrated to close the impedance control loop of the master robot. A force-position control algorithm is developed to control the hybrid actuated system. Teleoperated needle insertion is demonstrated under live MR imaging, where the slave robot resides in the scanner bore and the user manipulates the master beside the patient outside the bore. Force and position tracking results of the master-slave robot are demonstrated to validate the tracking performance of the integrated system. It has a position tracking error of 0.318mm and sine wave force tracking error of 2.227N.

  5. Teleoperation System with Hybrid Pneumatic-Piezoelectric Actuation for MRI-Guided Needle Insertion with Haptic Feedback

    Science.gov (United States)

    Shang, Weijian; Su, Hao; Li, Gang; Fischer, Gregory S.

    2014-01-01

    This paper presents a surgical master-slave tele-operation system for percutaneous interventional procedures under continuous magnetic resonance imaging (MRI) guidance. This system consists of a piezoelectrically actuated slave robot for needle placement with integrated fiber optic force sensor utilizing Fabry-Perot interferometry (FPI) sensing principle. The sensor flexure is optimized and embedded to the slave robot for measuring needle insertion force. A novel, compact opto-mechanical FPI sensor interface is integrated into an MRI robot control system. By leveraging the complementary features of pneumatic and piezoelectric actuation, a pneumatically actuated haptic master robot is also developed to render force associated with needle placement interventions to the clinician. An aluminum load cell is implemented and calibrated to close the impedance control loop of the master robot. A force-position control algorithm is developed to control the hybrid actuated system. Teleoperated needle insertion is demonstrated under live MR imaging, where the slave robot resides in the scanner bore and the user manipulates the master beside the patient outside the bore. Force and position tracking results of the master-slave robot are demonstrated to validate the tracking performance of the integrated system. It has a position tracking error of 0.318mm and sine wave force tracking error of 2.227N. PMID:25126446

  6. Model-based design and experimental verification of a monitoring concept for an active-active electromechanical aileron actuation system

    Science.gov (United States)

    Arriola, David; Thielecke, Frank

    2017-09-01

    Electromechanical actuators have become a key technology for the onset of power-by-wire flight control systems in the next generation of commercial aircraft. The design of robust control and monitoring functions for these devices capable to mitigate the effects of safety-critical faults is essential in order to achieve the required level of fault tolerance. A primary flight control system comprising two electromechanical actuators nominally operating in active-active mode is considered. A set of five signal-based monitoring functions are designed using a detailed model of the system under consideration which includes non-linear parasitic effects, measurement and data acquisition effects, and actuator faults. Robust detection thresholds are determined based on the analysis of parametric and input uncertainties. The designed monitoring functions are verified experimentally and by simulation through the injection of faults in the validated model and in a test-rig suited to the actuation system under consideration, respectively. They guarantee a robust and efficient fault detection and isolation with a low risk of false alarms, additionally enabling the correct reconfiguration of the system for an enhanced operational availability. In 98% of the performed experiments and simulations, the correct faults were detected and confirmed within the time objectives set.

  7. Piezoelectric actuators in the active vibration control system of journal bearings

    Science.gov (United States)

    Tůma, J.; Šimek, J.; Mahdal, M.; Pawlenka, M.; Wagnerova, R.

    2017-07-01

    The advantage of journal hydrodynamic bearings is high radial load capacity and operation at high speeds. The disadvantage is the excitation of vibrations, called an oil whirl, after crossing a certain threshold of the rotational speed. The mentioned vibrations can be suppressed using the system of the active vibration control with piezoactuators which move the bearing bushing. The motion of the bearing bushing is controlled by a feedback controller, which responds to the change in position of the bearing journal which is sensed by a pair of capacitive sensors. Two stacked linear piezoactuators are used to actuate the position of the bearing journal. This new bearing enables not only to damp vibrations but also serves to maintain the desired bearing journal position with an accuracy of micrometers. The paper will focus on the effect of active vibration control on the performance characteristics of the journal bearing.

  8. Output feedback control of linear fractional transformation systems subject to actuator saturation

    Science.gov (United States)

    Ban, Xiaojun; Wu, Fen

    2016-11-01

    In this paper, the control problem for a class of linear parameter varying (LPV) plant subject to actuator saturation is investigated. For the saturated LPV plant depending on the scheduling parameters in linear fractional transformation (LFT) fashion, a gain-scheduled output feedback controller in the LFT form is designed to guarantee the stability of the closed-loop LPV system and provide optimised disturbance/error attenuation performance. By using the congruent transformation, the synthesis condition is formulated as a convex optimisation problem in terms of a finite number of LMIs for which efficient optimisation techniques are available. The nonlinear inverted pendulum problem is employed to demonstrate the effectiveness of the proposed approach. Moreover, the comparison between our LPV saturated approach with an existing linear saturated method reveals the advantage of the LPV controller when handling nonlinear plants.

  9. Controllable nanoscale rotating actuator system based on carbon nanotube and graphene

    International Nuclear Information System (INIS)

    Huang, Jianzhang; Han, Qiang

    2016-01-01

    A controllable nanoscale rotating actuator system consisting of a double carbon nanotube and graphene driven by a temperature gradient is proposed, and its rotating dynamics performance and driving mechanism are investigated through molecular dynamics simulations. The outer tube exhibits stable pure rotation with certain orientation under temperature gradient and the steady rotational speed rises as the temperature gradient increases. It reveals that the driving torque is caused by the difference of atomic van der Waals potentials due to the temperature gradient and geometrical features of carbon nanotube. A theoretical model for driving torque is established based on lattice dynamics theory and its predicted results agree well with molecular dynamics simulations. Further discussion is taken according to the theoretical model. The work in this study would be a guide for design and application of controllable nanoscale rotating devices based on carbon nanotubes and graphene. (paper)

  10. ETHIOPIAN WITNESS PROTECTION SYSTEM: COMPARATIVE ...

    African Journals Online (AJOL)

    witness protection involves social cohesion of the protected person. Scholars ..... interests' need to balance an accused right to know and confront prosecution ..... was reduced to 2.5 years through the fast tracking of witness protection cases.

  11. Automatic control system of a linear actuator for positioning samples to neutron irradiation using low cost open-hardware boards

    International Nuclear Information System (INIS)

    Cunya, Eduardo; Chan, Renzo; Pacheco, Adison

    2015-01-01

    This paper describes the design criteria and implementation of an automatic control system based on embedded electronic circuits (microcontrollers) of different architectures (RISC, ARM) and open source framework software CanFestival, to develop user applications. Electronic devices are autonomous and support the functionality required for communication and remote control of the linear actuator. (author)

  12. 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.

  13. 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

  14. The primary protection system software

    International Nuclear Information System (INIS)

    Tooley, P.A.

    1992-01-01

    This paper continues the detailed description of the Primary Protection System for Sizewell-B by providing an overview of design and implementation of the software, including the features of the design process which ensure that quality is delivered by the contractor. The Nuclear Electric software assessment activities are also described. The argument for the excellence of the software is made on the basis of a quality product delivered by the equipment supplier's design process, and the confirmation of this provided by the Nuclear Electric assessment process, which is as searching and complete an examination as is reasonably practicable to achieve. (author)

  15. Wafer-scale integration of piezoelectric actuation capabilities in nanoelectromechanical systems resonators

    OpenAIRE

    DEZEST, Denis; MATHIEU, Fabrice; MAZENQ, Laurent; SOYER, Caroline; COSTECALDE, Jean; REMIENS, Denis; THOMAS, Olivier; DEÜ, Jean-François; NICU, Liviu

    2013-01-01

    In this work, we demonstrate the integration of piezoelectric actuation means on arrays of nanocantilevers at the wafer scale. We use lead titanate zirconate (PZT) as piezoelectric material mainly because of its excellent actuation properties even when geometrically constrained at extreme scale

  16. Parametric Design and Multiobjective Optimization of Maglev Actuators for Active Vibration Isolation System

    Directory of Open Access Journals (Sweden)

    Qianqian Wu

    2014-05-01

    Full Text Available The microvibration has a serious impact on science experiments on the space station and on image quality of high resolution satellites. As an important component of the active vibration isolation platform, the maglev actuator has a large stroke and exhibits excellent isolating performance benefiting from its noncontact characteristic. A maglev actuator with good linearity was designed in this paper. Fundamental features of the maglev actuator were obtained by finite element simulation. In order to minimize the coil weight and the heat dissipation of the maglev actuator, parametric design was carried out and multiobjective optimization based on the genetic algorithm was adopted. The optimized actuator has better mechanical properties than the initial one. Active vibration isolation platforms for different-scale payload were designed by changing the arrangement of the maglev actuators. The prototype to isolate vibration for small-scale payload was manufactured and the experiments for verifying the characteristics of the actuators were set up. The linearity of the actuator and the mechanical dynamic response of the vibration isolation platform were obtained. The experimental results highlight the effectiveness of the proposed design.

  17. Apparatus, system, and method for providing fabric-elastomer composites as pneumatic actuators

    Science.gov (United States)

    Martinez, Ramses V.; Whitesides, George M.

    2017-10-25

    Soft pneumatic actuators based on composites consisting of elastomers with embedded sheet or fiber structures (e.g., paper or fabric) that are flexible but not extensible are described. On pneumatic inflation, these actuators move anisotropically, based on the motions accessible by their composite structures. They are inexpensive, simple to fabricate, light in weight, and easy to actuate. This class of structure is versatile: the same principles of design lead to actuators that respond to pressurization with a wide range of motions (bending, extension, contraction, twisting, and others). Paper, when used to introduce anisotropy into elastomers, can be readily folded into three-dimensional structures following the principles of origami; these folded structures increase the stiffness and anisotropy of the elastomeric actuators, while keeping them light in weight.

  18. Toward Self-Control Systems for Neurogenic Underactive Bladder: A Triboelectric Nanogenerator Sensor Integrated with a Bistable Micro-Actuator.

    Science.gov (United States)

    Arab Hassani, Faezeh; Mogan, Roshini P; Gammad, Gil G L; Wang, Hao; Yen, Shih-Cheng; Thakor, Nitish V; Lee, Chengkuo

    2018-04-24

    Aging, neurologic diseases, and diabetes are a few risk factors that may lead to underactive bladder (UAB) syndrome. Despite all of the serious consequences of UAB, current solutions, the most common being ureteric catheterization, are all accompanied by serious shortcomings. The necessity of multiple catheterizations per day for a physically able patient not only reduces the quality of life with constant discomfort and pain but also can end up causing serious complications. Here, we present a bistable actuator to empty the bladder by incorporating shape memory alloy components integrated on flexible polyvinyl chloride sheets. The introduction of two compression and restoration phases for the actuator allows for repeated actuation for a more complete voiding of the bladder. The proposed actuator exhibits one of the highest reported voiding percentages of up to 78% of the bladder volume in an anesthetized rat after only 20 s of actuation. This amount of voiding is comparable to the common catheterization method, and its one time implantation onto the bladder rectifies the drawbacks of multiple catheterizations per day. Furthermore, the scaling of the device for animal models larger than rats can be easily achieved by adjusting the number of nitinol springs. For neurogenic UAB patients with degraded nerve function as well as degenerated detrusor muscle, we integrate a flexible triboelectric nanogenerator sensor with the actuator to detect the fullness of the bladder. The sensitivity of this sensor to the filling status of the bladder shows its capability for defining a self-control system in the future that would allow autonomous micturition.

  19. System architecture for microprocessor based protection system

    International Nuclear Information System (INIS)

    Gallagher, J.M. Jr.; Lilly, G.M.

    1976-01-01

    This paper discusses the architectural design features to be employed by Westinghouse in the application of distributed digital processing techniques to the protection system. While the title of the paper makes specific reference to microprocessors, this is only one (and the newest) of the building blocks which constitutes a distributed digital processing system. The actual system structure (as realized through utilization of the various building blocks) is established through considerations of reliability, licensability, and cost. It is the intent of the paper to address these considerations licenstions as they relate to the architectural design features. (orig.) [de

  20. Event-triggered decentralized adaptive fault-tolerant control of uncertain interconnected nonlinear systems with actuator failures.

    Science.gov (United States)

    Choi, Yun Ho; Yoo, Sung Jin

    2018-06-01

    This paper investigates the event-triggered decentralized adaptive tracking problem of a class of uncertain interconnected nonlinear systems with unexpected actuator failures. It is assumed that local control signals are transmitted to local actuators with time-varying faults whenever predefined conditions for triggering events are satisfied. Compared with the existing control-input-based event-triggering strategy for adaptive control of uncertain nonlinear systems, the aim of this paper is to propose a tracking-error-based event-triggering strategy in the decentralized adaptive fault-tolerant tracking framework. The proposed approach can relax drastic changes in control inputs caused by actuator faults in the existing triggering strategy. The stability of the proposed event-triggering control system is analyzed in the Lyapunov sense. Finally, simulation comparisons of the proposed and existing approaches are provided to show the effectiveness of the proposed theoretical result in the presence of actuator faults. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  1. Lightning Protection and Detection System

    Science.gov (United States)

    Dudley, Kenneth L. (Inventor); Szatkowski, George N. (Inventor); Woodard, Marie (Inventor); Nguyen, Truong X. (Inventor); Ely, Jay J. (Inventor); Wang, Chuantong (Inventor); Mielnik, John J. (Inventor); Koppen, Sandra V. (Inventor); Smith, Laura J. (Inventor)

    2017-01-01

    A lightning protection and detection system includes a non-conductive substrate material of an apparatus; a sensor formed of a conductive material and deposited on the non-conductive substrate material of the apparatus. The sensor includes a conductive trace formed in a continuous spiral winding starting at a first end at a center region of the sensor and ending at a second end at an outer corner region of the sensor, the first and second ends being open and unconnected. An electrical measurement system is in communication with the sensor and receives a resonant response from the sensor, to perform detection, in real-time, of lightning strike occurrences and damage therefrom to the sensor and the non-conductive substrate material.

  2. Improvement of the abnormal diagnosis technology by the development of an abnormal parts assignment system for the engineered safety features actuating system of the HTTR

    International Nuclear Information System (INIS)

    Hirato, Yoji; Kozawa, Takayuki; Saito, Kenji

    2015-01-01

    The safety protection sequence panel of HTTR is a control panel to actuate an engineering safety system for protecting the reactor core, reactor coolant pressure boundary, and containment vessel boundary at the time of an accident of the nuclear reactor facilities. The safety code stipulates that the control panel should receive safety check at a frequency of once a month during reactor operation. When abnormality has been found, it is required to eliminate its causes and restore normal operation as soon as possible. However, since this control panel is composed of a complex control circuit, the cause check during abnormality requires the confirmation by a knowledgeable person spending quite a lot of time for chart checking, which leads to a delay of restoration. To achieve a rapid restoration, the abnormal part assignment system (APAS), which can specify abnormality instantaneously even by a common operator, was developed. It has been confirmed that with this system, rapid initial response and prompt restoration can be effectively made. (A.O.)

  3. A solar energy powered autonomous wireless actuator node for irrigation systems.

    Science.gov (United States)

    Lajara, Rafael; Alberola, Jorge; Pelegrí-Sebastiá, José

    2011-01-01

    The design of a fully autonomous and wireless actuator node ("wEcoValve mote") based on the IEEE 802.15.4 standard is presented. The system allows remote control (open/close) of a 3-lead magnetic latch solenoid, commonly used in drip irrigation systems in applications such as agricultural areas, greenhouses, gardens, etc. The very low power consumption of the system in conjunction with the low power consumption of the valve, only when switching positions, allows the system to be solar powered, thus eliminating the need of wires and facilitating its deployment. By using supercapacitors recharged from a specifically designed solar power module, the need to replace batteries is also eliminated and the system is completely autonomous and maintenance free. The "wEcoValve mote" firmware is based on a synchronous protocol that allows a bidirectional communication with a latency optimized for real-time work, with a synchronization time between nodes of 4 s, thus achieving a power consumption average of 2.9 mW.

  4. A Solar Energy Powered Autonomous Wireless Actuator Node for Irrigation Systems

    Directory of Open Access Journals (Sweden)

    Rafael Lajara

    2010-12-01

    Full Text Available The design of a fully autonomous and wireless actuator node (“wEcoValve mote” based on the IEEE 802.15.4 standard is presented. The system allows remote control (open/close of a 3-lead magnetic latch solenoid, commonly used in drip irrigation systems in applications such as agricultural areas, greenhouses, gardens, etc. The very low power consumption of the system in conjunction with the low power consumption of the valve, only when switching positions, allows the system to be solar powered, thus eliminating the need of wires and facilitating its deployment. By using supercapacitors recharged from a specifically designed solar power module, the need to replace batteries is also eliminated and the system is completely autonomous and maintenance free. The “wEcoValve mote” firmware is based on a synchronous protocol that allows a bidirectional communication with a latency optimized for real-time work, with a synchronization time between nodes of 4 s, thus achieving a power consumption average of 2.9 mW.

  5. 1-D Wavelet Signal Analysis of the Actuators Nonlinearities Impact on the Healthy Control Systems Performance

    Directory of Open Access Journals (Sweden)

    Nicolae Tudoroiu

    2017-09-01

    Full Text Available The objective of this paper is to investigate the use of the 1-D wavelet analysis to extract several patterns from signals data sets collected from healthy and faulty input-output signals of control systems as a preliminary step in real-time implementation of fault detection diagnosis and isolation strategies. The 1-D wavelet analysis proved that is an useful tool for signals processing, design and analysis based on wavelet transforms found in a wide range of control systems industrial applications. Based on the fact that in the real life there is a great similitude between the phenomena, we are motivated to extend the applicability of these techniques to solve similar applications from control systems field, such is done in our research work. Their efficiency will be demonstrated on a case study mainly chosen to evaluate the impact of the uncertainties and the nonlinearities of the sensors and actuators on the overall performance of the control systems. The proposed techniques are able to extract in frequency domain some pattern features (signatures of interest directly from the signals data set collected by data acquisition equipment from the control system.

  6. Dynamic Stiffness Transfer Function of an Electromechanical Actuator Using System Identification

    Science.gov (United States)

    Kim, Sang Hwa; Tahk, Min-Jea

    2018-04-01

    In the aeroelastic analysis of flight vehicles with electromechanical actuators (EMAs), an accurate prediction of flutter requires dynamic stiffness characteristics of the EMA. The dynamic stiffness transfer function of the EMA with brushless direct current (BLDC) motor can be obtained by conducting complicated mathematical calculations of control algorithms and mechanical/electrical nonlinearities using linearization techniques. Thus, system identification approaches using experimental data, as an alternative, have considerable advantages. However, the test setup for system identification is expensive and complex, and experimental procedures for data collection are time-consuming tasks. To obtain the dynamic stiffness transfer function, this paper proposes a linear system identification method that uses information obtained from a reliable dynamic stiffness model with a control algorithm and nonlinearities. The results of this study show that the system identification procedure is compact, and the transfer function is able to describe the dynamic stiffness characteristics of the EMA. In addition, to verify the validity of the system identification method, the simulation results of the dynamic stiffness transfer function and the dynamic stiffness model were compared with the experimental data for various external loads.

  7. Wind turbine with lightning protection system

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to a wind turbine comprising a lightning protection system comprising a waveguide interconnecting a communication device and a signal-carrying structure. In other aspects, the present invention relates to the use of a waveguide in a lightning protection system...... of a wind turbine, a power splitter and its use in a lightning protection system of a wind turbine....

  8. Dynamics of a pneumatic artificial muscle actuation system driving a trailing edge flap

    Science.gov (United States)

    Woods, Benjamin K. S.; Kothera, Curt S.; Wang, Gang; Wereley, Norman M.

    2014-09-01

    This study presents a time domain dynamic model of an antagonistic pneumatic artificial muscle (PAM) driven trailing edge flap (TEF) system for next generation active helicopter rotors. Active rotor concepts are currently being widely researched in the rotorcraft community as a means to provide a significant leap forward in performance through primary aircraft control, vibration mitigation and noise reduction. Recent work has shown PAMs to be a promising candidate for active rotor actuation due to their combination of high force, large stroke, light weight, and suitable bandwidth. When arranged into biologically inspired agonist/antagonist muscle pairs they can produce bidirectional torques for effectively driving a TEF. However, there are no analytical dynamic models in the literature that can accurately capture the behavior of such systems across the broad range of frequencies required for this demanding application. This work combines mechanical, pneumatic, and aerodynamic component models into a global flap system model developed for the Bell 407 rotor system. This model can accurately predict pressure, force, and flap angle response to pneumatic control valve inputs over a range of operating frequencies from 7 to 35 Hz (1/rev to 5/rev for the Bell 407) and operating pressures from 30 to 90 psi.

  9. Dynamics of a pneumatic artificial muscle actuation system driving a trailing edge flap

    International Nuclear Information System (INIS)

    Woods, Benjamin K S; Kothera, Curt S; Wang, Gang; Wereley, Norman M

    2014-01-01

    This study presents a time domain dynamic model of an antagonistic pneumatic artificial muscle (PAM) driven trailing edge flap (TEF) system for next generation active helicopter rotors. Active rotor concepts are currently being widely researched in the rotorcraft community as a means to provide a significant leap forward in performance through primary aircraft control, vibration mitigation and noise reduction. Recent work has shown PAMs to be a promising candidate for active rotor actuation due to their combination of high force, large stroke, light weight, and suitable bandwidth. When arranged into biologically inspired agonist/antagonist muscle pairs they can produce bidirectional torques for effectively driving a TEF. However, there are no analytical dynamic models in the literature that can accurately capture the behavior of such systems across the broad range of frequencies required for this demanding application. This work combines mechanical, pneumatic, and aerodynamic component models into a global flap system model developed for the Bell 407 rotor system. This model can accurately predict pressure, force, and flap angle response to pneumatic control valve inputs over a range of operating frequencies from 7 to 35 Hz (1/rev to 5/rev for the Bell 407) and operating pressures from 30 to 90 psi. (paper)

  10. Closed-loop helium circulation system for actuation of a continuously operating heart catheter pump.

    Science.gov (United States)

    Karabegovic, Alen; Hinteregger, Markus; Janeczek, Christoph; Mohl, Werner; Gföhler, Margit

    2017-06-09

    Currently available, pneumatic-based medical devices are operated using closed-loop pulsatile or open continuous systems. Medical devices utilizing gases with a low atomic number in a continuous closed loop stream have not been documented to date. This work presents the construction of a portable helium circulation addressing the need for actuating a novel, pneumatically operated catheter pump. The design of its control system puts emphasis on the performance, safety and low running cost of the catheter pump. Static and dynamic characteristics of individual elements in the circulation are analyzed to ensure a proper operation of the system. The pneumatic circulation maximizes the working range of the drive unit inside the catheter pump while reducing the total size and noise production.Separate flow and pressure controllers position the turbine's working point into the stable region of the pressure creation element. A subsystem for rapid gas evacuation significantly decreases the duration of helium removal after a leak, reaching subatmospheric pressure in the intracorporeal catheter within several milliseconds. The system presented in the study offers an easy control of helium mass flow while ensuring stable behavior of its internal components.

  11. Automating occupational protection records systems

    International Nuclear Information System (INIS)

    Lyon, M.; Martin, J.B.

    1991-10-01

    Occupational protection records have traditionally been generated by field and laboratory personnel, assembled into files in the safety office, and eventually stored in a warehouse or other facility. Until recently, these records have been primarily paper copies, often handwritten. Sometimes, the paper is microfilmed for storage. However, electronic records are beginning to replace these traditional methods. The purpose of this paper is to provide guidance for making the transition to automated record keeping and retrieval using modern computer equipment. This paper describes the types of records most readily converted to electronic record keeping and a methodology for implementing an automated record system. The process of conversion is based on a requirements analysis to assess program needs and a high level of user involvement during the development. The importance of indexing the hard copy records for easy retrieval is also discussed. The concept of linkage between related records and its importance relative to reporting, research, and litigation will be addressed. 2 figs

  12. FPGA-Based Plant Protection System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yoon Hee; Ha, Jae Hong; Kim, Hang Bae [KEPCO E and C, Daejeon (Korea, Republic of)

    2011-08-15

    This paper relates to a plant protection system which detects non-permissible conditions and determines initiation of protective actions for nuclear power plants (NPPs). Conventional plant protection systems were designed based on analog technologies. It is well known that existing protection systems for NPPs contain many components which are becoming obsolete at an increasing rate. Nowadays maintenance and repair for analog-based plant protection systems may be difficult as analog parts become obsolete or difficult to obtain. Accordingly, as an alternative to the analog technology, the digitalisation of the plant protection system was required. Recently digital plant protection systems which include programmable logic controllers (PLCs) and/or computers have been introduced. However PLC or computer-based plant protection systems use an operating system and application software, and so they may result in a common mode failure when a problem occurs in the operating system or application software. Field Programmable Gate Arrays (FPGAs) are highlighted as an alternative to conventional protection or control systems. The paper presents the design of a four-channel plant protection system whose protection functions are implemented in FPGAs without any central processing unit or operating system.

  13. FPGA-Based Plant Protection System

    International Nuclear Information System (INIS)

    Lee, Yoon Hee; Ha, Jae Hong; Kim, Hang Bae

    2011-01-01

    This paper relates to a plant protection system which detects non-permissible conditions and determines initiation of protective actions for nuclear power plants (NPPs). Conventional plant protection systems were designed based on analog technologies. It is well known that existing protection systems for NPPs contain many components which are becoming obsolete at an increasing rate. Nowadays maintenance and repair for analog-based plant protection systems may be difficult as analog parts become obsolete or difficult to obtain. Accordingly, as an alternative to the analog technology, the digitalisation of the plant protection system was required. Recently digital plant protection systems which include programmable logic controllers (PLCs) and/or computers have been introduced. However PLC or computer-based plant protection systems use an operating system and application software, and so they may result in a common mode failure when a problem occurs in the operating system or application software. Field Programmable Gate Arrays (FPGAs) are highlighted as an alternative to conventional protection or control systems. The paper presents the design of a four-channel plant protection system whose protection functions are implemented in FPGAs without any central processing unit or operating system

  14. Deficiencies in radiation protection record systems

    International Nuclear Information System (INIS)

    Martin, J.B.; Lyon, M.

    1991-01-01

    Radiation protection records are a fundamental part of any program for protecting radiation workers. Records are essential to epidemiological studies of radiation workers and are becoming increasingly important as the number of radiation exposure litigation cases increases. Ready retrievability of comprehensive records is also essential to the adequate defense of a radiation protection program. Appraisals of numerous radiation protection programs have revealed that few record-keeping systems comply with American National Standards Institute, Standard Practice N13.6-1972. Record-keeping requirements and types of deficiencies in radiation protection records systems are presented in this paper, followed by general recommendations for implementing a comprehensive radiation protection records system

  15. Deficiencies in radiation protection record systems

    International Nuclear Information System (INIS)

    Martin, J.B.; Lyon, M.

    1991-01-01

    Radiation protection records are a fundamental part of any program for protecting radiation workers. Records are essential to epidemiological studies of radiation workers and are becoming increasingly important as the number of radiation exposure litigation cases increases. Ready retrievability of comprehensive records is also essential to the adequate defense of a radiation protection program. Appraisals of numerous radiation protection programs have revealed that few record-keeping systems comply with American National Standards Institute, Standard Practice N13.6-1972. Record-keeping requirements and types of deficiencies in radiation protection records systems are presented in this paper, followed by general recommendations for implementing a comprehensive radiation protection records system. 8 refs

  16. Digital protection in power plants. Electrical unit and line protection. Digital protection systems for NPP

    International Nuclear Information System (INIS)

    Kaczmarek, A.

    2000-01-01

    In this presentation author deals with the digital protection systems for nuclear power plants. The evolution of protection devices, protection concept for power plants, concept of functional redundancy, references for digital protection, benefits for the customer well as concept fault recorder are presented. (author)

  17. Ageing study of the engineered safety features actuation system of the Loviisa NPP

    International Nuclear Information System (INIS)

    Simola, K.; Maskuniitty, M.

    1995-06-01

    An ageing study of the engineered safety features actuation system of the Loviisa nuclear power plant has been performed. The operating experience, including failure and maintenance histories of analog measuring devices, logics for safety signal formation and individual control electronics of pumps and valves, has been collected and analysed. The safety importance of system components has been studied with a fault tree analysis of a selected safety function. Based on the results of the analysis of operating experiences and the fault tree analysis, some components were selected for deeper analyses. According to the operating experience, the amount of failures in the Loviisa plant safety system has been low and no increasing trend in the failure history can yet be observed. Only a few failures had prohibited the propagation of the safety signal, mostly the failures have caused a false alarm. The failures reported have concerned mainly limit signal units, transmitters, and priority units. According to the fault tree analysis of one safety function, the most important components of this subsystem are individual control units and pulse/DC converters. Failure modes and effect analyses were performed for priority and individual control unit, limit signal unit and comparator and pulse/DC converter in order to identify the critical failure modes of these devices. (orig.) (15 refs., 26 figs., 9 tabs.)

  18. Linear Extended State Observer-Based Motion Synchronization Control for Hybrid Actuation System of More Electric Aircraft

    Directory of Open Access Journals (Sweden)

    Xingjian Wang

    2017-10-01

    Full Text Available Moving towards the more electric aircraft (MEA, a hybrid actuator configuration provides an opportunity to introduce electromechanical actuator (EMA into primary flight control. In the hybrid actuation system (HAS, an electro-hydraulic servo actuator (EHSA and an EMA operate on the same control surface. In order to solve force fighting problem in HAS, this paper proposes a novel linear extended state observer (LESO-based motion synchronization control method. To cope with the problem of unavailability of the state signals required by the motion synchronization controller, LESO is designed for EHSA and EMA to observe the state variables. Based on the observed states of LESO, motion synchronization controllers could enable EHSA and EMA to simultaneously track the desired motion trajectories. Additionally, nonlinearities, uncertainties and unknown disturbances as well as the coupling term between EHSA and EMA can be estimated and compensated by using the extended state of the proposed LESO. Finally, comparative simulation results indicate that the proposed LESO-based motion synchronization controller could reduce significant force fighting between EHSA and EMA.

  19. Linear Extended State Observer-Based Motion Synchronization Control for Hybrid Actuation System of More Electric Aircraft

    Science.gov (United States)

    Liao, Rui; Shi, Cun; Wang, Shaoping

    2017-01-01

    Moving towards the more electric aircraft (MEA), a hybrid actuator configuration provides an opportunity to introduce electromechanical actuator (EMA) into primary flight control. In the hybrid actuation system (HAS), an electro-hydraulic servo actuator (EHSA) and an EMA operate on the same control surface. In order to solve force fighting problem in HAS, this paper proposes a novel linear extended state observer (LESO)-based motion synchronization control method. To cope with the problem of unavailability of the state signals required by the motion synchronization controller, LESO is designed for EHSA and EMA to observe the state variables. Based on the observed states of LESO, motion synchronization controllers could enable EHSA and EMA to simultaneously track the desired motion trajectories. Additionally, nonlinearities, uncertainties and unknown disturbances as well as the coupling term between EHSA and EMA can be estimated and compensated by using the extended state of the proposed LESO. Finally, comparative simulation results indicate that the proposed LESO-based motion synchronization controller could reduce significant force fighting between EHSA and EMA. PMID:29068392

  20. Development of an Upper Limb Power Assist System Using Pneumatic Actuators for Farming Lift-up Motion

    Science.gov (United States)

    Yagi, Eiichi; Harada, Daisuke; Kobayashi, Masaaki

    A power assist system has lately attracted considerable attention to lifting-up an object without low back pain. We have been developing power assist systems with pneumatic actuators for the elbow and shoulder to farming support of lifting-up a bag of rice weighing 30kg. This paper describes the mechanism and control method of this power assist system. The pneumatic rotary actuator supports shoulder motion, and the air cylinder supports elbow motion. In this control method, the surface electromyogram(EMG) signals are used as input information of the controller. The joint support torques of human are calculated based on the antigravity term of necessary joint torques, which are estimated on the dynamics of a human approximated link model. The experimental results show the effectiveness of the proposed mechanism and control method of the power assist system.

  1. Study of damping in 5 kWh superconductor flywheel energy storage system using a piezoelectric actuator

    Energy Technology Data Exchange (ETDEWEB)

    Jang, H.K.; Song, D.; Kim, S.B. [Hanyang University, 17 Haengdang-Dong, Seongdong-Gu, Seoul 133-791 (Korea, Republic of); Han, S.C. [Korea Electric Power Research Institute, 103-16 Munji-Ro, Yuseong-Gu, Daejeon 305-380 (Korea, Republic of); Sung, T.H., E-mail: sungth@hanyang.ac.kr [Hanyang University, 17 Haengdang-Dong, Seongdong-Gu, Seoul 133-791 (Korea, Republic of)

    2012-05-15

    A 5 kWh superconductor flywheel energy storage system (SFES) has advantages in terms of high electrical energy density, environmental affinity and long life. However, the SFES has disadvantage that electromagnetic damper is needed because superconducting bearings do not have enough damping coefficient. The purpose of this experiment is to develop a method of damping the vibration of the SFES. A piezoelectric actuator was attached to a superconducting bearing system for feasibility test in order to make it as a damper of the SFES. For this experiment, a cylindrical permanent magnet (PM) 40 mm in diameter and 10 mm height was used as a rotor, a high-temperature superconductor bulk (HTS bulk) with dimensions 40 mm Multiplication-Sign 40 mm Multiplication-Sign 15 mm was used as a stator, and two vibration exciters (an upper and a lower vibration exciter) and a piezoelectric actuator were used. The PM was fixed on the upper vibration exciter. The HTS bulk was fixed on either the lower vibration exciter to test for damping in the feasibility test, or on the piezoelectric actuator for the actual SFES. The conditions of this experiment included various voltage outputs of a power amplifier to the lower vibration exciter, moving distances of the piezoelectric actuator which are displacements of the HTS bulk, and phase differences between the upper and lower vibration exciter or the piezoelectric actuator. The damping feasibility test was conducted with a 300 {mu}m gap between the PM and HTS bulk with a PM vibration of 30 {mu}m. For the actual SFES test, the gap between the PM and HTS bulk was 1.6 mm and the PM vibration was 25 {mu}m. The following conditions were conducted to optimize: an appropriate voltage input to the lower vibration exciter or a displacement of piezoelectric actuator and an appropriate phase difference. When the piezoelectric actuator was used, the damping effect was greatly improved up to 92.32% which a displacement of damped PM was 1.92 {mu}m.

  2. Refillable and magnetically actuated drug delivery system using pear-shaped viscoelastic membrane

    KAUST Repository

    So, Hongyun; Seo, Young Ho; Pisano, Albert P.

    2014-01-01

    We report a refillable and valveless drug delivery device actuated by an external magnetic field for on-demand drug release to treat localized diseases. The device features a pear-shaped viscoelastic magnetic membrane inducing asymmetrical

  3. The UC Softhand: Light Weight Adaptive Bionic Hand with a Compact Twisted String Actuation System

    Directory of Open Access Journals (Sweden)

    Mahmoud Tavakoli

    2015-12-01

    Full Text Available In this paper, we present the design and development of the UC-Softhand. The UC Softhand is a low cost, Bionic and adaptive hand that takes advantage of compliant joints. By optimization of the actuation strategy as well as the actuation mechanism, we could develop an anthropomorphic hand that embeds three actuators, transmission mechanisms, controllers and drivers in the palm of the hand, and weighs only 280 g, making it one of the lightest bionic hands that has been created so far. The key aspect of the UC Softhand is utilization of a novel compact twisted string actuation mechanism, that allows a considerable weight and cost reduction compared to its predecessor.

  4. Distributed radiation protection console system

    International Nuclear Information System (INIS)

    Chhokra, R.S.; Deshpande, V.K.; Mishra, H.; Rajeev, K.P.; Thakur, Bipla B.; Munj, Niket

    2004-01-01

    Radiation exposure control is one of the most important aspects in any nuclear facility . It encompasses continuous monitoring of the various areas of the facility to detect any increase in the radiation level and/or the air activity level beyond preset limits and alarm the O and M personnel working in these areas. Detection and measurement of radiation level and the air activity level is carried out by a number of monitors installed in the areas. These monitors include Area Gamma Monitors, Continuous Air Monitors, Pu-In-Air Monitors, Criticality Monitors etc. Traditionally, these measurements are displayed and recorded on a Central Radiation Protection Console(CRPC), which is located in the central control room of the facility. This methodology suffers from the shortcoming that any worker required to enter a work area will have to inquire about the radiation status of the area either from the CRPC or will get to know the same directly from the installed only after entering the area. This shortcoming can lead to avoidable delays in attending to the work or to unwanted exposure. The authors have designed and developed a system called Distributed Radiation Protection Console (DRPC) to overcome this shortcoming. A DRPC is a console which is located outside the entrance of a given area and displays the radiation status of the area. It presents to health physicist and the plant operators a graphic over-view of the radiation and air activity levels in the particular area of the plant. It also provides audio visual annunciation of the alarm status. Each radioactive area in a nuclear facility will have its own DRPC, which will receive as its inputs the analog and digital signals from radiation monitoring instruments installed in the area and would not only show those readings on its video graphic screen but will also provide warning messages and instructions to the personnel entering the active areas. The various DRPCs can be integrated into a Local Area Network, where the

  5. Teleoperation System with Hybrid Pneumatic-Piezoelectric Actuation for MRI-Guided Needle Insertion with Haptic Feedback

    OpenAIRE

    Shang, Weijian; Su, Hao; Li, Gang; Fischer, Gregory S.

    2013-01-01

    This paper presents a surgical master-slave tele-operation system for percutaneous interventional procedures under continuous magnetic resonance imaging (MRI) guidance. This system consists of a piezoelectrically actuated slave robot for needle placement with integrated fiber optic force sensor utilizing Fabry-Perot interferometry (FPI) sensing principle. The sensor flexure is optimized and embedded to the slave robot for measuring needle insertion force. A novel, compact opto-mechanical FPI ...

  6. Chapter 2. Mode-switching in Hydraulic Actuator Systems - An Experiment

    DEFF Research Database (Denmark)

    Andersen, Torben Ole; Conrad, Finn; Ravn, Anders P.

    1996-01-01

    Experiments with mode-switching adaptive control of actuators to drive a hydraulic test robot.The research is a cooperation with IT, DTU within the IMCIA Research Programme supported by the Danish Technical Research Council, STVF.......Experiments with mode-switching adaptive control of actuators to drive a hydraulic test robot.The research is a cooperation with IT, DTU within the IMCIA Research Programme supported by the Danish Technical Research Council, STVF....

  7. Vertical comb drive actuator for the measurement of piezoelectric coefficients in small-scale systems

    International Nuclear Information System (INIS)

    Wooldridge, J; Muniz-Piniella, A; Stewart, M; Shean, T A V; Weaver, P M; Cain, M G

    2013-01-01

    A micro-electro-mechanical systems (MEMS) vertical levitation comb drive actuator has been created for the measurement of piezoelectric coefficients in thin/thick films or piezoelectrically active micro-scale components of other MEMS devices. The device exerts a dynamic force of 33 μN at an applied voltage of 100 V. The charge developed on the piezoelectric test device is measured using a charge sensitive pre-amplifier and lock-in technique, enabling measurements down to 1×10 −5 pC. The system was tested with ten different piezoelectric samples with coefficients in the range 70–1375 pC N −1 and showed a good correlation (r = 0.9997) to measurements performed with macroscopic applied stresses, and piezoelectric impedance resonance techniques. The measurement of the direct piezoelectric effect in micro- and nano-scale piezo-materials has been made possible using MEMS processing technology. This new application of a MEMS metrology device has been developed and fully characterized in order to accurately evaluate the functional properties of piezoelectric materials at the scale required in micro- to nano-scale applications. (paper)

  8. Near-surface gravity actuated pipe (GAP{sup TM}) system for Brazilian deepwater fluid transfer

    Energy Technology Data Exchange (ETDEWEB)

    Fromage, Lionel; Brown, Paul A. [SBM Offshore (Monaco)

    2009-12-19

    The recent discovery of new deep water and ultra-deep water oil and gas fields offshore Brazil, including pre-salt reservoirs, has become a focal point for field development Operators and Contractors. The aggressive nature of fluids (sour, high density) in combination with deeper waters implies potential flow assurance issues. These issues challenge riser and pipeline technology to find cost effective solutions for hydrocarbon fluid transfer in field development scenarios involving phased tied-back. The near-surface GAP{sup TM}, system (Gravity Actuated Pipe{sup TM}), which has been in operation for more than two years on the Kikeh field offshore Malaysia in 1325 m of water between a Dry Tree Unit (SPAR) and a turret-moored FPSO, is considered to meet these challenges since such a product is quasi independent of water depth and takes advantage of being near surface to optimize flow assurance. Furthermore the GAP{sup TM} has undergone technical upgrades when compared to the Kikeh project in order to make it suitable for the more hostile met ocean conditions offshore Brazil. This paper presents the design features, the construction and assembly plans in Brazil and the offshore installation of a GAP fluid transfer system for operation in Brazilian deep waters. (author)

  9. Piezoelectrically Actuated Robotic System for MRI-Guided Prostate Percutaneous Therapy

    Science.gov (United States)

    Su, Hao; Shang, Weijian; Cole, Gregory; Li, Gang; Harrington, Kevin; Camilo, Alexander; Tokuda, Junichi; Tempany, Clare M.; Hata, Nobuhiko; Fischer, Gregory S.

    2014-01-01

    This paper presents a fully-actuated robotic system for percutaneous prostate therapy under continuously acquired live magnetic resonance imaging (MRI) guidance. The system is composed of modular hardware and software to support the surgical workflow of intra-operative MRI-guided surgical procedures. We present the development of a 6-degree-of-freedom (DOF) needle placement robot for transperineal prostate interventions. The robot consists of a 3-DOF needle driver module and a 3-DOF Cartesian motion module. The needle driver provides needle cannula translation and rotation (2-DOF) and stylet translation (1-DOF). A custom robot controller consisting of multiple piezoelectric motor drivers provides precision closed-loop control of piezoelectric motors and enables simultaneous robot motion and MR imaging. The developed modular robot control interface software performs image-based registration, kinematics calculation, and exchanges robot commands and coordinates between the navigation software and the robot controller with a new implementation of the open network communication protocol OpenIGTLink. Comprehensive compatibility of the robot is evaluated inside a 3-Tesla MRI scanner using standard imaging sequences and the signal-to-noise ratio (SNR) loss is limited to 15%. The image deterioration due to the present and motion of robot demonstrates unobservable image interference. Twenty-five targeted needle placements inside gelatin phantoms utilizing an 18-gauge ceramic needle demonstrated 0.87 mm root mean square (RMS) error in 3D Euclidean distance based on MRI volume segmentation of the image-guided robotic needle placement procedure. PMID:26412962

  10. Prototype Control System for Compensation of Superconducting Cavities Detuning Using Piezoelectric Actuators

    Science.gov (United States)

    Przygoda, K.; Piotrowski, A.; Jablonski, G.; Makowski, D.; Pozniak, T.; Napieralski, A.

    2009-08-01

    Pulsed operation of high gradient superconducting radio frequency (SCRF) cavities results in dynamic Lorentz force detuning (LFD) approaching or exceeding the bandwidth of the cavity of order of a few hundreds of Hz. The resulting modulation of the resonance frequency of the cavity is leading to a perturbation of the amplitude and phase of the accelerating field, which can be controlled only at the expense of RF power. Presently, at various labs, a piezoelectric fast tuner based on an active compensation scheme for the resonance frequency control of the cavity is under study. The tests already performed in the Free Electron Laser in Hamburg (FLASH), proved the possibility of Lorentz force detuning compensation by the means of the piezo element excited with the single period of sine wave prior to the RF pulse. The X-Ray Free Electron Laser (X-FEL) accelerator, which is now under development in Deutsche Elektronen-Synchrotron (DESY), will consists of around 800 cavities with a fast tuner fixture including the actuator/sensor configuration. Therefore, it is necessary to design a distributed control system which would be able to supervise around 25 RF stations, each one comprised of 32 cavities. The Advanced Telecomunications Computing Architecture (ATCA) was chosen to design, develop, and build a Low Level Radio Frequency (LLRF) controller for X-FEL. The prototype control system for Lorentz force detuning compensation was designed and developed. The control applications applied in the system were fitted to the main framework of interfaces and communication protocols proposed for the ATCA-based LLRF control system. The paper presents the general view of a designed control system and shows the first experimental results from the tests carried out in FLASH facility. Moreover, the possibilities for integration of the piezo control system to the ATCA standards are discussed.

  11. Identity management and witness protection system

    OpenAIRE

    Paunović, Saša; Starčević, Dušan; Nešić, Lazar

    2013-01-01

    The protection of participants in criminal proceedings is one of the most important tools for prosecution of war crimes and organized crime cases. The paper presents the basic characteristics and the importance of implementing the Program of protection in criminal proceedings, with emphasis on the protection system and management of identity. Special attention was paid to challenges facing the protection system in criminal proceedings and the management of identities, which are caused by the ...

  12. Adaptive fuzzy observer-based stabilization of a class of uncertain time-delayed chaotic systems with actuator nonlinearities

    International Nuclear Information System (INIS)

    Shahnazi, Reza; Haghani, Adel; Jeinsch, Torsten

    2015-01-01

    An observer-based output feedback adaptive fuzzy controller is proposed to stabilize a class of uncertain chaotic systems with unknown time-varying time delays, unknown actuator nonlinearities and unknown external disturbances. The actuator nonlinearity can be backlash-like hysteresis or dead-zone. Based on universal approximation property of fuzzy systems the unknown nonlinear functions are approximated by fuzzy systems, where the consequent parts of fuzzy rules are tuned with adaptive schemes. The proposed method does not need the availability of the states and an observer based output feedback approach is proposed to estimate the states. To have more robustness and at the same time to alleviate chattering an adaptive discontinuous structure is suggested. Semi-global asymptotic stability of the overall system is ensured by proposing a suitable Lyapunov–Krasovskii functional candidate. The approach is applied to stabilize the time-delayed Lorenz chaotic system with uncertain dynamics amid significant disturbances. Analysis of simulations reveals the effectiveness of the proposed method in terms of coping well with the modeling uncertainties, nonlinearities in actuators, unknown time-varying time-delays and unknown external disturbances while maintaining asymptotic convergence

  13. Reactor protection and shut-down system

    International Nuclear Information System (INIS)

    Klar

    1980-01-01

    The reactor protection system being a part of the reactor safety system. The requirements on the reactor protection system are: high safety with regard to signal processing, high availability, self-reporting of faults etc. The functional sections of the reactor protection system are the analog section, the logic section and the generating of output signals. Description of the operation characteristics and of the extension of function. (orig.)

  14. Physical protection system design and evaluation

    International Nuclear Information System (INIS)

    Williams, J.D.

    1997-01-01

    The design of an effective physical protection system includes the determination of physical protection system objectives, initial design of a physical protection system, design evaluation, and probably a redesign or refinement. To develop the objectives, the designer must begin by gathering information about facility operation and conditions, such as a comprehensive description of the facility, operating conditions, and the physical protection requirements. The designer then needs to define the threat. This involves considering factors about potential adversaries: class of adversary, adversary's capabilities, and range of adversary's tactics. Next, the designer should identify targets. Determination of whether or not the materials being protected are attractive targets is based mainly on the ease or difficulty of acquisition and desirability of the material. The designer now knows the objectives of the physical protection system, that is, open-quotes what to protect against whom.close quotes The next step is to design the system by determining how best to combine such elements as fences, vaults, sensors and assessment devices, entry control elements, procedures, communication devices, and protective forces personnel to meet the objectives of the system. Once a physical protection system is designed, it must be analyzed and evaluated to ensure it meets the physical protection objectives. Evaluation must allow for features working together to ensure protection rather than regarding each feature separately. Due to the complexity of the protection systems, an evaluation usually requires modeling techniques. If any vulnerabilities are found, the initial system must be redesigned to correct the vulnerabilities and a reevaluation conducted. This paper reviews the physical protection system design and methodology mentioned above. Examples of the steps required and a brief introduction to some of the technologies used in modem physical protections system are given

  15. Failsafe design criteria for computer based reactor protection systems

    International Nuclear Information System (INIS)

    Keats, A.B.

    1980-01-01

    The design criteria proposed are an extrapolation of the failsafe mode of operation used in the UK in hardwired reactor protection systems. This is achieved by making the operational condition of the reactor dependent upon an energetic state of the protection system components. An important objective of the proposed design criteria is to eliminate, or at least to minimize, the need for a failure-mode-and-effect-analysis (FMEA) of the computer software. This demands some well defined but simple constraints upon the way in which data are stored in the computers, but the objective is achieved almost entirely by hardware properties of the system. The first of these is the systematic use of hardwired test inputs which cause transient excursions into the tripped state in a uniquely ordered but easily recognizable sequence. The second is the use of hardwired pattern recognition logic which generates a dynamic healthy stimulus for the shutdown actuators only in response to the unique sequence formed by the hardwired input signal pattern. It therefore detects abnormal states of any of the system inputs, software errors, wiring errors and hardware failures. This hardwired logic is conceptually simple, failsafe, and is amenable to simple FMEA. (U.K.)

  16. On line test of trip channels and actuators in primary shutdown system for RAPP-3,4/KAIGA-1,2 reactors

    International Nuclear Information System (INIS)

    Pramanik, M.; Gupta, P.K.; Ravi Prakash

    1997-01-01

    Several types of system design and logic arrangements have been used for reactor shutdown systems to avoid the possibility that a single failure within the trip channels/shutdown system actuators can prevent a shutdown system actuation. The trip channels and the logic arrangements associated with the shutdown systems use redundancy to allow them to continue to operate successfully even after having a certain number of failures. A periodic test is thus needed to detect and repair/replace failed elements to prevent accumulation and eventual system failure. The test must be capable of detecting the first failure. The design initiates shutdown system actuation by deenergising the logic relays and turning off the power to the final electrical actuators. Thus, the systems are fail safe with respect to loss of electrical power to the instruments, logic channels and the actuators. Several system/logic arrangements are used to reduce the chances of spurious actuation caused by the loss of a single power supply and other single failures. In general, the systems use coincidence of instrument channel trips and have separate power supplies for the individual instrument channel and dual power supplies where a single final control element is used. These features also permit on line test of instrument channels and logic train. On line test detects component failures not found by other means. The test determines whether gross failure has occurred rather than perform a calibration. As far as practicable the whole channel from sensors to logic and final control element is to be tested. (author)

  17. A Statistical Methodology for Determination of Safety Systems Actuation Setpoints Based on Extreme Value Statistics

    Directory of Open Access Journals (Sweden)

    D. R. Novog

    2008-01-01

    Full Text Available This paper provides a novel and robust methodology for determination of nuclear reactor trip setpoints which accounts for uncertainties in input parameters and models, as well as accounting for the variations in operating states that periodically occur. Further it demonstrates that in performing best estimate and uncertainty calculations, it is critical to consider the impact of all fuel channels and instrumentation in the integration of these uncertainties in setpoint determination. This methodology is based on the concept of a true trip setpoint, which is the reactor setpoint that would be required in an ideal situation where all key inputs and plant responses were known, such that during the accident sequence a reactor shutdown will occur which just prevents the acceptance criteria from being exceeded. Since this true value cannot be established, the uncertainties in plant simulations and plant measurements as well as operational variations which lead to time changes in the true value of initial conditions must be considered. This paper presents the general concept used to determine the actuation setpoints considering the uncertainties and changes in initial conditions, and allowing for safety systems instrumentation redundancy. The results demonstrate unique statistical behavior with respect to both fuel and instrumentation uncertainties which has not previously been investigated.

  18. Air microjet system for non-contact force application and the actuation of micro-structures

    International Nuclear Information System (INIS)

    Khare, S M; Venkataraman, V

    2016-01-01

    We demonstrate a non-contact technique to apply calibrated and localized forces in the micro-Newton to milli-Newton range using an air microjet. An electromagnetically actuated diaphragm controlled by a signal generator is used to generate the air microjet. With a nozzle diameter of 150 μm, the microjet diameter was maintained to a maximum of 1 mm at a distance of 5 mm from the nozzle. The force generated by the microjet was measured using a commercial force sensor to determine the velocity profile of the jet. Axial flow velocities of up to 25 m s −1 were obtained at distances as long as 6 mm. The microjet exerted a force up to 1 μN on a poly dimethyl siloxane (PDMS) micropillar (50 μm in diameter, 157 μm in height) and 415 μN on a PDMS membrane (3 mm in diameter, 28 μm thick). We also demonstrate that from a distance of 6 mm our microjet can exert a peak pressure of 187 Pa with a total force of about 84 μN on a flat surface with 8 V operating voltage. Out of the cleanroom fabrication and robust design make this system cost effective and durable. (technical note)

  19. Air microjet system for non-contact force application and the actuation of micro-structures

    Science.gov (United States)

    Khare, S. M.; Venkataraman, V.

    2016-01-01

    We demonstrate a non-contact technique to apply calibrated and localized forces in the micro-Newton to milli-Newton range using an air microjet. An electromagnetically actuated diaphragm controlled by a signal generator is used to generate the air microjet. With a nozzle diameter of 150 μm, the microjet diameter was maintained to a maximum of 1 mm at a distance of 5 mm from the nozzle. The force generated by the microjet was measured using a commercial force sensor to determine the velocity profile of the jet. Axial flow velocities of up to 25 m s-1 were obtained at distances as long as 6 mm. The microjet exerted a force up to 1 μN on a poly dimethyl siloxane (PDMS) micropillar (50 μm in diameter, 157 μm in height) and 415 μN on a PDMS membrane (3 mm in diameter, 28 μm thick). We also demonstrate that from a distance of 6 mm our microjet can exert a peak pressure of 187 Pa with a total force of about 84 μN on a flat surface with 8 V operating voltage. Out of the cleanroom fabrication and robust design make this system cost effective and durable.

  20. Sensing and actuation system for the University of Florida Torsion Pendulum for LISA

    Science.gov (United States)

    Chilton, Andrew; Shelley, Ryan; Olatunde, Taiwo; Ciani, Giacomo; Conklin, John; Mueller, Guido

    2014-03-01

    Space-based gravitational wave detectors like LISA are a necessity for understanding the low-frequency portion of the gravitational universe. They use test masses (TMs) which are separated by Gm and are in free fall inside their respective spacecraft. Their relative distance is monitored with laser interferometry at the pm/rtHz level in the LISA band, ranging from 0.1 to 100 mHz. Each TM is enclosed in a housing that provides isolation, capacitive sensing, and electrostatic actuation capabilities. The electronics must both be sensitive at the 1 nm/rtHz level and not induce residual acceleration noise above the requirement for LISA Pathfinder (3*10-15 m/sec2Hz1/2at 3 mHz). Testing and developing this technology is one of the roles of the University of Florida Torsion Pendulum, the only US testbed for LISA-like gravitational reference sensor technology. Our implementation of the sensing system functions by biasing our hollow LISA-like TMs with a 100 kHz sine wave and coupling a pair surrounding electrodes as capacitors to a pair of preamps and a differential amplifier; all other processing is done digitally. Here we report on the design of, implementation of, and preliminary results from the UF Torsion Pendulum.

  1. Active fault tolerance control of a wind turbine system using an unknown input observer with an actuator fault

    Directory of Open Access Journals (Sweden)

    Li Shanzhi

    2018-03-01

    Full Text Available This paper proposes a fault tolerant control scheme based on an unknown input observer for a wind turbine system subject to an actuator fault and disturbance. Firstly, an unknown input observer for state estimation and fault detection using a linear parameter varying model is developed. By solving linear matrix inequalities (LMIs and linear matrix equalities (LMEs, the gains of the unknown input observer are obtained. The convergence of the unknown input observer is also analysed with Lyapunov theory. Secondly, using fault estimation, an active fault tolerant controller is applied to a wind turbine system. Finally, a simulation of a wind turbine benchmark with an actuator fault is tested for the proposed method. The simulation results indicate that the proposed FTC scheme is efficient.

  2. LHC magnet quench protection system

    Science.gov (United States)

    Coull, L.; Hagedorn, D.; Remondino, V.; Rodriguez-Mateos, F.

    1994-07-01

    The quench protection system for the superconducting magnets of the CERN Large Hadron Collider (LHC) is described. The system is based on the so called 'cold diode' concept. In a group of series connected magnets if one magnet quenches then the magnetic energy of all the magnets will be dissipated in the quenched magnet so destroying it. This is avoided by by-passing the quenched magnet and then rapidly de-exciting the unquenched magnets. For the LHC machine it is foreseen to use silicon diodes situated inside the cryostat as by-pass elements - so called 'cold diodes'. The diodes are exposed to some 50 kGray of radiation during a 10 year operation life-time. The high energy density of the LHC magnets (500 kJ/m) coupled with the relatively slow propagation speed of a 'natural' quench (10 to 20 m/s) can lead to excessive heating of the zone where the quench started and to high internal voltages. It is therefore necessary to detect quickly the incipient quench and fire strip heaters which spread the quench out more quickly over a large volume of the magnet. After a quench the magnet chain must be de-excited rapidly to avoid spreading the quench to other magnets and over-heating the by-pass diode. This is done by switching high-power energy-dump resistors in series with the magnets. The LHC main ring magnet will be divided into 16 electrically separated units which has important advantages.

  3. LHC magnet quench protection system

    International Nuclear Information System (INIS)

    Coull, L.; Hagedorn, D.; Remondino, V.; Rodriguez-Mateos, F.

    1994-01-01

    The quench protection system for the superconducting magnets of the CERN Large Hadron Collider (LHC) is described. The system is based on the so called ''cold diode'' concept. In a group of series connected magnets if one magnet quenches then the magnetic energy of all the magnets will be dissipated in the quenched magnet so destroying it. This is avoided by by-passing the quenched magnet and then rapidly de-exciting the unquenched magnets. For the LHC machine it is foreseen to use silicon diodes situated inside the cryostat as by-pass elements--so called ''cold diodes''. The diodes are exposed to some 50 kGray of radiation during a 10 year operation life-time. The high energy density of the LHC magnets (500 kJ/m) coupled with the relatively slow propagation speed of a ''natural'' quench (10 to 20 m/s) can lead to excessive heating of the zone where the quench started and to high internal voltages. It is therefore necessary to detect quickly the incipient quench and fire strip heaters which spread the quench out more quickly over a large volume of the magnet. After a quench the magnet chain must be de-excited rapidly to avoid spreading the quench to other magnets and over-heating the by-pass diode. This is done by switching high-power energy-dump resistors in series with the magnets. The LHC main ring magnet will be divided into 16 electrically separated units which has important advantages

  4. Electroactive Polymer (EAP) Actuation of Mechanisms and Robotic Devices

    Science.gov (United States)

    Bar-Cohen, Y.; Leary, S.; Harrison, J.; Smith, J.

    1999-01-01

    Actuators are responsible to the operative capability of manipulation systems and robots. In recent years, electroactive polymers (EAP) have emerged as potential alternative to conventional actuators.

  5. Protective and Catching Safety Systems In Construction

    Directory of Open Access Journals (Sweden)

    Kuzhin Marat

    2017-01-01

    Full Text Available In the article is described application of protective and catching systems in construction. Classification of similar systems, their types and purpose are listed. Dangerous zones on construction site and events to for limiting their influence or protection from the factors. Protective and catching systems is one of the most effective technical equipment, applied in recent time. Protective fences and catching systems are important part in the problem solution. Protective fences protect workers from falling from height. Protective and catching systems allows avoid injuries by workers, also catch debris, fallen from constructing buildings. In regard with continuing development in technical and technological solutions, protective and catching systems require adaptation to a new requirements of construction industry and requirements of normative documents. Technical regulations in the appliance sphere of protective and catching systems requires actualization and aligning with modern normatives. Important role should be given to developing organizational and technological documentation for application of the systems. Scientific studying of technical parameters of fences and protective catching nets also has great interest.

  6. RIVER PROTECTION PROJECT SYSTEM PLAN

    Energy Technology Data Exchange (ETDEWEB)

    CERTA PJ

    2008-07-10

    The U.S. Department of Energy (DOE), Office of River Protection (ORP) manages the River Protection Project (RPP). The RPP mission is to retrieve and treat Hanford's tank waste and close the tank farms to protect the Columbia River. As a result, the ORP is responsible for the retrieval, treatment, and disposal of the approximately 57 million gallons of radioactive waste contained in the Hanford Site waste tanks and closure of all the tanks and associated facilities. The previous revision of the System Plan was issued in September 2003. ORP has approved a number of changes to the tank waste treatment strategy and plans since the last revision of this document, and additional changes are under consideration. The ORP has established contracts to implement this strategy to establish a basic capability to complete the overall mission. The current strategy for completion of the mission uses a number of interrelated activities. The ORP will reduce risk to the environment posed by tank wastes by: (1) Retrieving the waste from the single-shell tanks (SST) to double-shell tanks (DST) for treatment and disposal; (2) Constructing and operating the WTP, which will safely treat all of the high-level waste (HLW) and about half of the low-activity waste (LAW) contained in the tank farms, and maximizing its capability and capacity; (3) Developing and deploying supplemental treatment capability or a second WTP LAW Facility that can safely treat about half of the LAW contained in the tank farms; (4) Developing and deploying treatment and packaging capability for transuranic (TRU) tank waste for shipment to and disposal at the Waste Isolation Pilot Plant (WIPP); (5) Deploying interim storage capacity for the immobilized HLW and shipping that waste to Yucca Mountain for disposal; (6) Operating the Integrated Disposal Facility for the disposal of immobilized LAW, along with the associated secondary waste, (7) Closing the SST and DST tank farms, ancillary facilities, and al1 waste

  7. RIVER PROTECTION PROJECT SYSTEM PLAN

    International Nuclear Information System (INIS)

    CERTA PJ

    2008-01-01

    The U.S. Department of Energy (DOE), Office of River Protection (ORP) manages the River Protection Project (RPP). The RPP mission is to retrieve and treat Hanford's tank waste and close the tank farms to protect the Columbia River. As a result, the ORP is responsible for the retrieval, treatment, and disposal of the approximately 57 million gallons of radioactive waste contained in the Hanford Site waste tanks and closure of all the tanks and associated facilities. The previous revision of the System Plan was issued in September 2003. ORP has approved a number of changes to the tank waste treatment strategy and plans since the last revision of this document, and additional changes are under consideration. The ORP has established contracts to implement this strategy to establish a basic capability to complete the overall mission. The current strategy for completion of the mission uses a number of interrelated activities. The ORP will reduce risk to the environment posed by tank wastes by: (1) Retrieving the waste from the single-shell tanks (SST) to double-shell tanks (DST) for treatment and disposal; (2) Constructing and operating the WTP, which will safely treat all of the high-level waste (HLW) and about half of the low-activity waste (LAW) contained in the tank farms, and maximizing its capability and capacity; (3) Developing and deploying supplemental treatment capability or a second WTP LAW Facility that can safely treat about half of the LAW contained in the tank farms; (4) Developing and deploying treatment and packaging capability for transuranic (TRU) tank waste for shipment to and disposal at the Waste Isolation Pilot Plant (WIPP); (5) Deploying interim storage capacity for the immobilized HLW and shipping that waste to Yucca Mountain for disposal; (6) Operating the Integrated Disposal Facility for the disposal of immobilized LAW, along with the associated secondary waste, (7) Closing the SST and DST tank farms, ancillary facilities, and al1 waste

  8. The information protection level assessment system implementation

    Science.gov (United States)

    Trapeznikov, E. V.

    2018-04-01

    Currently, the threat of various attacks increases significantly as automated systems become more widespread. On the basis of the conducted analysis the information protection level assessment system establishing objective was identified. The paper presents the information protection level assessment software implementation in the information system by applying the programming language C #. In conclusions the software features are identified and experimental results are represented.

  9. Regulatory control of physical protection systems

    International Nuclear Information System (INIS)

    Rajdeep; Mayya, Y.S.

    2017-01-01

    The safety of facilities in BARC is under the regulatory oversight of BSC. The security architecture for these facilities incorporates multiple layers of Physical Protection Systems. The demands of safety may sometimes conflict with the needs of security. Realizing the need to identify these interfaces and extend the regulatory coverage to Physical Protection Systems, a Standing Committee named Physical Protection System Review Committee (PPSRC) has been constituted as a 2"n"d tier entity of BSC. PPSRC includes experts from various domains concerned with nuclear security, viz. physical protection systems, cyber security, radiation safety, security operations, technical services and security administration

  10. RIVER PROTECTION PROJECT SYSTEM PLAN

    International Nuclear Information System (INIS)

    Certa, P.J.; Kirkbride, R.A.; Hohl, T.M.; Empey, P.A.; Wells, M.N.

    2009-01-01

    The U.S. Department of Energy (DOE), Office of River Protection (ORP) manages the River Protection Project (RPP). The RPP mission is to retrieve and treat Hanford's tank waste and close the tank farms to protect the Columbia River. As a result, ORP is responsible for the retrieval, treatment, and disposal of approximately 57 million gallons 1 of radioactive waste contained in the Hanford Site waste tanks and closure2 of all the tanks and associated facilities. The previous revision of the System Plan was issued in May 2008. ORP has made a number of changes to the tank waste treatment strategy and plans since the last revision of this document, and additional changes are under consideration. ORP has contracts in place to implement the strategy for completion of the mission and establish the capability to complete the overall mission. The current strategl involves a number of interrelated activities. ORP will reduce risk to the environment posed by tank wastes by the following: (1) Retrieving the waste from the single-shell tanks (SST) to double-shell tanks (DST) and delivering the waste to the Waste Treatment and Immobilization Plant (WTP). (2) Constructing and operating the WTP, which will safely treat all of the high-level waste (HLW) fraction contained in the tank farms. About one-third of the low-activity waste (LAW) fraction separated from the HLW fraction in the WTP will be immobilized in the WTP LAW Vitrification Facility. (3) Developing and deploying supplemental treatment capability assumed to be a second LAW vitrification facility that can safely treat about two-thirds of the LAW contained in the tank farms. (4) Developing and deploying supplemental pretreatment capability currently assumed to be an Aluminum Removal Facility (ARF) using a lithium hydrotalcite process to mitigate sodium management issues. (5) Developing and deploying treatment and packaging capability for contact-handled transuranic (CH-TRU) tank waste for possible shipment to and disposal

  11. RIVER PROTECTION PROJECT SYSTEM PLAN

    Energy Technology Data Exchange (ETDEWEB)

    CERTA PJ; KIRKBRIDE RA; HOHL TM; EMPEY PA; WELLS MN

    2009-09-15

    The U.S. Department of Energy (DOE), Office of River Protection (ORP) manages the River Protection Project (RPP). The RPP mission is to retrieve and treat Hanford's tank waste and close the tank farms to protect the Columbia River. As a result, ORP is responsible for the retrieval, treatment, and disposal of approximately 57 million gallons 1 of radioactive waste contained in the Hanford Site waste tanks and closure2 of all the tanks and associated facilities. The previous revision of the System Plan was issued in May 2008. ORP has made a number of changes to the tank waste treatment strategy and plans since the last revision of this document, and additional changes are under consideration. ORP has contracts in place to implement the strategy for completion of the mission and establish the capability to complete the overall mission. The current strategl involves a number of interrelated activities. ORP will reduce risk to the environment posed by tank wastes by the following: (1) Retrieving the waste from the single-shell tanks (SST) to double-shell tanks (DST) and delivering the waste to the Waste Treatment and Immobilization Plant (WTP). (2) Constructing and operating the WTP, which will safely treat all of the high-level waste (HLW) fraction contained in the tank farms. About one-third of the low-activity waste (LAW) fraction separated from the HLW fraction in the WTP will be immobilized in the WTP LAW Vitrification Facility. (3) Developing and deploying supplemental treatment capability assumed to be a second LAW vitrification facility that can safely treat about two-thirds of the LAW contained in the tank farms. (4) Developing and deploying supplemental pretreatment capability currently assumed to be an Aluminum Removal Facility (ARF) using a lithium hydrotalcite process to mitigate sodium management issues. (5) Developing and deploying treatment and packaging capability for contact-handled transuranic (CH-TRU) tank waste for possible shipment to and

  12. Refillable and magnetically actuated drug delivery system using pear-shaped viscoelastic membrane

    KAUST Repository

    So, Hongyun

    2014-07-01

    We report a refillable and valveless drug delivery device actuated by an external magnetic field for on-demand drug release to treat localized diseases. The device features a pear-shaped viscoelastic magnetic membrane inducing asymmetrical deflection and consecutive touchdown motion to the bottom of the dome-shaped drug reservoir in response to a magnetic field, thus achieving controlled discharge of the drug. Maximum drug release with 18 ± 1.5 μg per actuation was achieved under a 500 mT magnetic flux density, and various controlled drug doses were investigated with the combination of the number of accumulated actuations and the strength of the magnetic field.

  13. SPIN. First Digital Protection System Feedback of experience ... ... after 30 years

    International Nuclear Information System (INIS)

    Kosicki, M.; Pacuta, J.; Kamga, J.; Burel, J.-P.

    2010-01-01

    In this lecture Mr Burel presents experience with the software SPIN - the first digital protection system feedback. After thirty years of operation, the results are positive: - System is in correct operation and still maintained with spare parts available; - No spurious trip or actuation due to the system itself. A project for modernization is prepared to replace the digital part with a new digital technology designed with today's: - Components (SPINLINE 3); - methods and tools (Software development); - Standards (EMI/RFI - qualification), in order to allow customer to add some new functional needs and to keep the system in operation for thirty more years.

  14. Design Of Photovoltaic Powered Cathodic Protection System

    Directory of Open Access Journals (Sweden)

    Golina Samir Adly

    2017-07-01

    Full Text Available The corrosion caused by chemical reaction between metallic structures and surrounding mediums such as soil or water .the CP cathodic protection system is used to protect metallic structure against corrosion. Cathodic protection CP used to minimize corrosion by utilizing an external source of electrical current which forces the entire structure to become a cathode. There are two Types of cathodic protection system Galvanic current Impressed current.the Galvanic current is called a sacrificial anode is connected to the protected structure cathode through a DC power supply. In Galvanic current system a current passes from the sacrificing anode to the protected structure .the sacrificial anode is corroded rather than causing the protected structure corrosion .protected structure requires a constant current to stop the corrosion which determined by area structure metal and the surrounding medium. The rains humidity are decrease soil resistivity and increase the DC current .The corrosion and over protection resulting from increase in the DC current is harmful for the metallic structure. This problem can be solved by conventional cathodic protection system by manual adjustment of DC voltage periodically to obtain a constant current .the manual adjustment of DC voltage depends on experience of the technician and using the accuracy of the measuring equipment. The errors of measuring current depend on error from the technician or error from the measuring equipment. the corrosion of structure may occur when the interval between two successive adjustment is long .An automatically regulated cathodic protection system is used to overcome problems from conventional cathodic protection system .the regulated cathodic protection system adjust the DC voltage of the system automatically when it senses the variations of surrounding medium resistivity so the DC current is constant at the required level.

  15. Italy: Analysis of Solutions for Passively Actuated Safety Shutdown Devices

    International Nuclear Information System (INIS)

    Burgazzi, L.

    2015-01-01

    This article looks at different special shutdown systems specifically engineered for prevention of severe accidents, to be implemented on Fast Reactors, with main focus on the investigation of the performance of the self-actuated shutdown systems in Sodium Fast Reactors. The passive shut-down systems are designed to shut-down system only by inherent passive reactivity feedback mechanism, under unprotected accident conditions, implying failure of reactor protection system. They are conceived to be self-actuated without any signal elaboration, since the actuation of the system is triggered by the effects induced by the transient like material dilatation, in case of overheating of the coolant for instance, according to Fast Reactor design to meet the safety requirements

  16. Towards Sensor-Actuator Coupling in an Automated Order Picking System by Detecting Sealed Seams on Pouch Packed Goods

    Directory of Open Access Journals (Sweden)

    Frank Weichert

    2014-10-01

    Full Text Available In this paper, a novel concept of coupling the actuators of an automated order picking system for pouch packed goods with an embedded CCD camera sensor by means of image processing and machine learning is presented. The picking system mechanically combines the conveyance and singularization of a still-connected chain of pouch packed goods in a single machinery. The proposed algorithms perform a per-frame processing of the captured images in real-time to detect the sealed seams of the ongoing pouches. The detections are used to deduce cutting decisions in order to control the system’s actuators, namely the drive pulley for conveyance and the cutting device for the separation. Within this context, two controlling strategies are presented as well which specify the interaction of the sensor and the actuators. The detection is carried out by two different marker detection strategies: enhanced Template Matching as a heuristic and Support Vector Machines as a supervised classification based concept. Depending on the employed marker, detection rates of almost 100% with a calculation time of less than 40 ms are possible. From a logistic point of view, sealed seam widths of 20 mm prove feasible.

  17. FY1995 study of aid system for the elderly and the disabled using metal hydride alloy actuators; 1995 nendo suiso kyuzo gokingata actuator ni yoru kaijo shien system no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Purpose of the project is to develop a transfer aid system for the elderly who need assistance in moving from a bed or a chair. It can make up insufficiency of assistant persons and can help to comfortably move the elderly. It has the highest demand in rehabilitation centers or hospitals. We have been designing an actuator using a metal hydride alloy for more than ten years and have confirmed that the actuator is very useful for developing the transfer. Furthermore, we have designed the transfer from a view point of human interfaces. This research was done under the above background. 1. We studied a comfortable posture for the elderly at an initial phase of standing to design the optimal knee pad using a life-size model of a transfer. Especially, we managed to lighten the burden imposed on the elderly by referring electromyographic signals at lower limbs and ground reaction forces. 2. Since the tactile sensation of the bottom of elderly person's foot gets dull, we designed a foot stage to prevent the elderly from the dull. 3. We determined the optimal mixture rate of a metal hydride alloy and developed an elastic bellows in order to design the actuator used for the transfer aid. 4. We determined the optimal compliance to prevent the elderly from a mechanical shock and designed a mechanism so that the transfer aid can work well. 5. Based on the above results, we developed the transfer aid using the metal hydride actuator. It was ascertained that it can lift a elderly person with 80kg weight by using only 40g alloy. Furthermore, it is proved that the transfer is not heavy (about 20g weight), small, silent, and moves smoothly by a battery on the market. (NEDO)

  18. Analysis of the sweeped actuator line method

    OpenAIRE

    Nathan Jörn; Masson Christian; Dufresne Louis; Churchfield Matthew

    2015-01-01

    The actuator line method made it possible to describe the near wake of a wind turbine more accurately than with the actuator disk method. Whereas the actuator line generates the helicoidal vortex system shed from the tip blades, the actuator disk method sheds a vortex sheet from the edge of the rotor plane. But with the actuator line come also temporal and spatial constraints, such as the need for a much smaller time step than with actuator disk. While the latter one only has to obey the Cour...

  19. Advanced physical protection systems for nuclear materials

    International Nuclear Information System (INIS)

    Jones, O.E.

    1975-10-01

    Because of the increasing incidence of terrorism, there is growing concern that nuclear materials and facilities need improved physical protection against theft, diversion, or sabotage. Physical protection systems for facilities or transportation which have balanced effectiveness include information systems, access denial systems, adequate and timely response, recovery capability, and use denial methods for despoiling special nuclear materials (SNM). The role of these elements in reducing societal risk is described; however, it is noted that, similar to nuclear war, the absolute risks of nuclear theft and sabotage are basically unquantifiable. Sandia Laboratories has a major Energy Research and Development Administration (ERDA) role in developing advanced physical protection systems for improving the security of both SNM and facilities. These activities are surveyed. A computer simulation model is being developed to assess the cost-effectiveness of alternative physical protection systems under various levels of threat. Improved physical protection equipment such as perimeter and interior alarms, secure portals, and fixed and remotely-activated barriers is being developed and tested. In addition, complete prototype protection systems are being developed for representative nuclear facilities. An example is shown for a plutonium storage vault. The ERDA safe-secure transportation system for highway shipments of all significant quantities of government-owned SNM is described. Adversary simulation as a tool for testing and evaluating physical protection systems is discussed. A list of measures is given for assessing overall physical protection system performance. (auth)

  20. Advanced physical protection systems for nuclear materials

    International Nuclear Information System (INIS)

    Jones, O.E.

    1976-01-01

    Because of the increasing incidence of terrorism, there is growing concern that nuclear materials and facilities need improved physical protection against theft, diversion, or sabotage. Physical protection systems for facilities or transportation which have balanced effectiveness include information systems, access denial systems, adequate and timely response, recovery capability, and use denial methods for despoiling special nuclear materials (SNM). The role of these elements in reducing societal risk is described; however, it is noted that, similar to nuclear war, the absolute risks of nuclear theft and sabotage are basically unquantifiable. Sandia Laboratories has a major US Energy Research and Development Administration (ERDA) role in developing advanced physical protection systems for improving the security of both SNM and facilities. These activities are surveyed in this paper. A computer simulation model is being developed to assess the cost-effectiveness of alternative physical protection systems under various levels of threat. Improved physical protection equipment such as perimeter and interior alarms, secure portals, and fixed and remotely activated barriers is being developed and tested. In addition, complete prototype protection systems are being developed for representative nuclear facilities. An example is shown for a plutonium storage vault. The ERDA safe-secure transportation system for highway shipments of all significant quantities of government-owned SNM is described. Adversary simulation as a tool for testing and evaluating physical protection systems is discussed. Finally, a list of measures is given for assessing overall physical protection system performance. (author)

  1. Real time plasma control experiments using the JET auxiliary plasma heating systems as the actuator

    International Nuclear Information System (INIS)

    Zornig, N.H.

    1999-01-01

    The role of the Real Time Power Control system (RTPC) in the Joint European Torus (JET) is described in depth. The modes of operation are discussed in detail and a number of successful experiments are described. These experiments prove that RTPC can be used for a wide range of experiments, including: (1) Feedback control of plasma parameters in real time using Ion Cyclotron Resonance Heating (ICRH) or Neutral Beam Heating (NBH) as the actuator in various JET operating regimes. It is demonstrated that in a multi-parameter space it is not sufficient to control one global plasma parameter in order to avoid performance limiting events. (2) Restricting neutron production and subsequent machine activation resulting from high performance pulses. (3) The simulation of α-particle heating effects in a DT-plasma in a D-only plasma. The heating properties of α-particles are simulated using ICRH-power, which is adjusted in real time. The simulation of α-particle heating in JET allows the effects of a change in isotopic mass to be separated from α-particle heating. However, the change in isotopic mass of the plasma ions appears to affect not only the global energy confinement time (τ E ) but also other parameters such as the electron temperature at the plasma edge. This also affects τ E , making it difficult to make a conclusive statement about any isotopic effect. (4) For future JET experiments a scheme has been designed which simulates the behaviour of a fusion reactor experimentally. The design parameters of the International Thermonuclear Experimental Reactor (ITER) are used. In the proposed scheme the most relevant dimensionless plasma parameters are similar in JET and ITER. It is also shown how the amount of heating may be simulated in real time by RTPC using the electron temperature and density as input parameters. The results of two demonstration experiments are presented. (author)

  2. Programmed system for nuclear power plant protection

    International Nuclear Information System (INIS)

    Jover, Pierre.

    1980-06-01

    The progress in the field of microprocessors and large scale integration circuits, have incited to introduce this new technologies into nuclear power plant protection system. The hardware and software design principles are briefly listed; then, a quad-redundant protection system for 1300 MWe PWR, developed in France is described [fr

  3. Phase lag deduced information in photo-thermal actuation for nano-mechanical systems characterization

    NARCIS (Netherlands)

    Bijster, R.J.F.; Vreugd, J. de; Sadeghian Marnani, H.

    2014-01-01

    In photo-thermal actuation, heat is added locally to a micro-cantilever by means of a laser. A fraction of the irradiation is absorbed, yielding thermal stresses and deformations in the structure. Harmonic modulation of the laser power causes the cantilever to oscillate. Moreover, a phase lag is

  4. Efficient control of servo pneumatic actuator system utilizing by-pass ...

    Indian Academy of Sciences (India)

    chambers within one actuator for recycling of exhaust compressed air. Wang et al (2000) ... possible or to use compressed air from the previous working chamber entirely or partly for the ..... 52 (weeks) × 5 (days) × 2 (shifts) ×. 8 h = 4160 h per ...

  5. Worcester 1 Inch Solenoid-Actuated Gas-Operated VPS System Ball Valve

    International Nuclear Information System (INIS)

    VAN KATWIJK, C.

    2000-01-01

    1 inch Gas-operated full-port ball valve incorporates a solenoid and limit switches as integral parts of the actuator. The valve is normally open and fails safe to the closed position. The associated valve position switch is class GS

  6. Availability analysis of supervised protective systems

    International Nuclear Information System (INIS)

    Kontoleon, N.; Kontoleon, J.M.; Chrysochoides, N.G.

    1975-01-01

    The behaviour in time of a nuclear reactor supervised protective system is modelled mathematically by a Markov process, continuous in time and with three discrete states. Failure and repair rates are assumed to be exponentially distributed. An analytical expression of system availability as a function of failure and repair rates as well as the inspection intervals and duration is derived. An optimization problem is then discussed in order to maximize system availability with respect to imposed cost constraints. Finally, an example of a supervised protective system with short inactive times is given, which may be found in many practical situations of modern protective systems. (author)

  7. A Michelson interferometer system for testing the stability of a piezo-electric actuator intended for use in space

    International Nuclear Information System (INIS)

    Aplin, K L; Middleton, K F

    2007-01-01

    The Laser Interferometer Space Antenna (LISA) experiment will search for gravitational waves generated by cataclysmic events far back in astronomical history. LISA is an interferometer formed by three spacecraft positioned five million km apart, and to observe gravitational waves, it must monitor test mass positions with picometre level resolution. One of the numerous technological challenges is to identify an actuator with appropriate accuracy, precision and stability for positioning of the optical fibres used to deliver LISA's laser sources. We have developed a Michelson interferometer system to determine the temporal and thermal stability of candidate actuators, with an emphasis on characterisation in the milliHertz frequency range required for gravitational wave detection in space. This paper describes the interferometer data logging and calibration and presents preliminary results in the form of a 'noise spectrum' generated from the small perturbation of a nominally static mirror. The maximum displacement of the mirror was ∼50 nm with sub-Hz noise levels of 0.1-1 nm√Hz. This is within the LISA noise specification, and confirms that the apparatus is stable enough for the characterisation of the actuator

  8. An integrated system for physical protection

    International Nuclear Information System (INIS)

    Kumar, Ranajit

    2001-01-01

    An Integrated Physical Protection System (IPPS) was developed for the consolidation of all sub systems, sensors and elements related to physical protection for an efficient and effective security environment of a facility. An effective physical protection system discharges the functions of detection, delay, communication, response, access control etc. IPPS performs, controls and monitors all the above functionality and helps in taking quick action on occurrence of unusual incidents by instantly reporting the incident in easily understandable audio, video, graphical and textual format and also by initiating automatic interactions among sub-systems

  9. Aging assessment for active fire protection systems

    International Nuclear Information System (INIS)

    Ross, S.B.; Nowlen, S.P.; Tanaka, T.

    1995-06-01

    This study assessed the impact of aging on the performance and reliability of active fire protection systems including both fixed fire suppression and fixed fire detection systems. The experience base shows that most nuclear power plants have an aggressive maintenance and testing program and are finding degraded fire protection system components before a failure occurs. Also, from the data reviewed it is clear that the risk impact of fire protection system aging is low. However, it is assumed that a more aggressive maintenance and testing program involving preventive diagnostics may reduce the risk impact even further

  10. Outer skin protection of columbium Thermal Protection System (TPS) panels

    Science.gov (United States)

    Culp, J. D.

    1973-01-01

    A coated columbium alloy material system 0.04 centimeter thick was developed which provides for increased reliability to the load bearing character of the system in the event of physical damage to and loss of the exterior protective coating. The increased reliability to the load bearing columbium alloy (FS-85) was achieved by interposing an oxidation resistant columbium alloy (B-1) between the FS-85 alloy and a fused slurry silicide coating. The B-1 alloy was applied as a cladding to the FS-85 and the composite was fused slurry silicide coated. Results of material evaluation testing included cyclic oxidation testing of specimens with intentional coating defects, tensile testing of several material combinations exposed to reentry profile conditions, and emittance testing after cycling of up to 100 simulated reentries. The clad material, which was shown to provide greater reliability than unclad materials, holds significant promise for use in the thermal protection system of hypersonic reentry vehicles.

  11. On line protection systems for induction motors

    International Nuclear Information System (INIS)

    Colak, I.; Celik, H.; Sefa, I.; Demirbas, S.

    2005-01-01

    Protection of induction motors is very important since they are widely used in industry for many applications due to their high robustness, reliability, low cost and maintenance, high efficiency and long service life. So, protecting these motors is crucial for operations. This paper presents a combined protection approach for induction motors. To achieve this, the electrical values of the induction motor were measured with sensitivity ±1% through a data acquisition card and processed with software developed in Visual C++. An on line protection system for induction motors was achieved easily and effectively. The experimental results have shown that the induction motor was protected against the possible problems faced during the operation. The software developed for this protection provides flexible and reliable media for operators and their motors. It is expected that the motor protection achieved in this study might be faster than the classical techniques and also may be applied to larger motors easily after small modifications of the software

  12. Design, construction and implementation of two redundant circuits of the actuation logic of the protection system of the new control console of TRIGA Mark III reactor of ININ; Diseno, construccion e implementacion de dos circuitos redundantes de la logica de actuacion del sistema de proteccion de la nueva consola de control del reactor Triga Mark III del ININ

    Energy Technology Data Exchange (ETDEWEB)

    Celestino M, E.

    2016-07-01

    The Instituto Nacional de Investigaciones Nucleares (ININ) in Mexico has a nuclear reactor type TRIGA Mark III, which was put into operation in 1968. The reactor is used for staff training, radioisotope production, and for research projects of different areas. Over time and due to advances constantly has the electronics industry, maintenance of electronic systems is complicated because basically sometimes components that are no longer manufactured or no longer exist in the market, making it necessary to create projects required modernization. This is the case of the TRIGA reactor of ININ, so the Department of Automation and Instrumentation ININ is undertaking a new project to update the reactor control console. Systems that make up a nuclear reactor protection system (Ps) is relevant, since it is responsible for generating the necessary steps to shut down the reactor to an event of uncertainty which could affect the operators or the installation own actions. As part of the renovation project, this study design is presented to update the Logic of Action (La) of the Ps, whose final design must meet the requirements or specifications set by users and or regulations applicable to nuclear research reactors. One of the requirements established for the proposed new design La, is that it must be implemented with components and devices manufactured with latest technologies, and readily available on the market. The design which is operating currently uses TTL logic whose components are no longer available in the market, so for the new design you decide to use programmable circuits, and specifically, the CPLDs called (by the acronym Complex Programmable Logic Device). These CPLDs are electronic devices that solve complex logic equations and meeting the requirements of functionality and modernity for the new design of the La. In this work the criteria used for the selection of the CPLDs considering the availability and ease of software and hardware to use, and the design and

  13. Testing Digital Electronic Protection Systems

    CERN Document Server

    Gabourin, S

    2011-01-01

    This paper outlines the core concepts and realisation of the Safe Machine Parameters Controller (SMPC) testbench, based on a VME crate and LabVIEW program. Its main goal is to ensure the correct function of the SMPC for the protection of the CERN accelerator complex. To achieve this, the tester has been built to replicate the machine environment and operation, in order to ensure that the chassis under test is completely exercised. The complexity of the task increases with the number of input combinations. This paper also outlines the benefits and weaknesses of developing a test suite independently of the hardware being tested, using the “V” approach.

  14. Hydraulically actuated artificial muscles

    Science.gov (United States)

    Meller, M. A.; Tiwari, R.; Wajcs, K. B.; Moses, C.; Reveles, I.; Garcia, E.

    2012-04-01

    Hydraulic Artificial Muscles (HAMs) consisting of a polymer tube constrained by a nylon mesh are presented in this paper. Despite the actuation mechanism being similar to its popular counterpart, which are pneumatically actuated (PAM), HAMs have not been studied in depth. HAMs offer the advantage of compliance, large force to weight ratio, low maintenance, and low cost over traditional hydraulic cylinders. Muscle characterization for isometric and isobaric tests are discussed and compared to PAMs. A model incorporating the effect of mesh angle and friction have also been developed. In addition, differential swelling of the muscle on actuation has also been included in the model. An application of lab fabricated HAMs for a meso-scale robotic system is also presented.

  15. Integrated crop protection as a system approach

    OpenAIRE

    Haan, de, J.J.; Wijnands, F.G.; Sukkel, W.

    2005-01-01

    New farming systems in vegetable production are required as demands for high quality products that do not pollute the environment are rising, and production risks are large and incomes low. The methodology of prototyping new systems is described, especially the themes, parameters and target values connected to integrated crop protection. The role of integrated crop protection in prototyping new systems is discussed. The results of twenty years working with this prototyping methodology are pre...

  16. A protection system for picosecond accelerator

    International Nuclear Information System (INIS)

    Cao Hongping; Chinese Academy of Sciences, Beijing; Chen Huanguang; Xu Ruinian; Tang Junlong; Li Deming

    2006-01-01

    A personnel and machine protection system for the picosecond accelerator has been built. The key of the system is to send on/off of three triggering signals which are those of electron gun, 2856 MHz and 476 MHz, respectively, to ensure the safety of users and the accelerator. This paper describes the emergencies interlocked by ADAM5511 and timing trigger processor, and some secondary functions which improve the efficiency of the protection system completed in upper layer software. (authors)

  17. Temperature sensitive self-actuated scram mechanism

    International Nuclear Information System (INIS)

    1980-01-01

    The apparatus, described in detail, accurately infers the average coolant temperature exiting from the reactor core in a liquid metal cooled reactor and rapidly and reliably actuates a safety rod release mechanism on the occurrence of a critical temperature. The output temperature is inferred from the cooperative effect of the flow rate through a coolant flow path within the safety assembly and the heat generated by sensor fuel pins. The inferred temperature is sensed by a confined fluid having a high expansion coefficient; the expansion is transferred to a linear force used to actuate the release mechanism. The system may be contained within the safety assembly and does not interfere with the operation of the plant protection system scram mode. It is resetable after a scram. The time interval between the overtemperature and the insertion of the safety rods is short enough to preclude fuel damage. (U.K.)

  18. Explosion-protected electric heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Elsner, H

    1984-02-01

    Different constructions of explosion-protected heating systems are described concerning the different types of protection, the service conditions, the installation and the surveillance devices. Interpretations and regulations derived from the VDE Standards are discussed and their relation to the European Standards EN 50014 ... 50020 is considered in a survey.

  19. Microsoft System Center Data Protection Manager 2012

    CERN Document Server

    Buchannan, Steve; Gomaa, Islam

    2013-01-01

    This book is a Packt tutorial, walking the administrator through the steps needed to create real solutions to the problems and tasks faced when ensuring that their data is protected. This book is for network administrators, system administrators, backup administrators, or IT consultants who are looking to expand their knowledge on how to utilize DPM to protect their organization's data.

  20. Analog subsystem for the plutonium protection system

    International Nuclear Information System (INIS)

    Arlowe, H.D.

    1978-12-01

    An analog subsystem is described which monitors certain functions in the Plutonium Protection System. Rotary and linear potentiometer output signals are digitized, as are the outputs from thermistors and container ''bulge'' sensors. This work was sponsored by the Department of Energy/Office of Safeguards and Security (DOE/OSS) as part of the overall Sandia Fixed Facility Physical Protection Program

  1. Worcester 1 Inch Solenoid-Actuated Gas Operated SCHe System Valves

    International Nuclear Information System (INIS)

    VAN KATWIJK, C.

    2000-01-01

    1 inch Gas-operated full-port ball valves incorporate a solenoid and limit switches as integral parts of the actuator. These valves are normally open and fail safe to the open position (GOV-1*02 and 1*06 fail closed) to provide a flow path of helium gas to the MCO under helium purge and off-normal conditions when the MCO is isolated

  2. Systems and methods for photovoltaic string protection

    Science.gov (United States)

    Krein, Philip T.; Kim, Katherine A.; Pilawa-Podgurski, Robert C. N.

    2017-10-25

    A system and method includes a circuit for protecting a photovoltaic string. A bypass switch connects in parallel to the photovoltaic string and a hot spot protection switch connects in series with the photovoltaic string. A first control signal controls opening and closing of the bypass switch and a second control signal controls opening and closing of the hot spot protection switch. Upon detection of a hot spot condition the first control signal closes the bypass switch and after the bypass switch is closed the second control signal opens the hot spot protection switch.

  3. Relay protection coordination with generator capability curve, excitation system limiters and power system relay protections settings

    Directory of Open Access Journals (Sweden)

    Buha Danilo

    2016-01-01

    Full Text Available The relay protection settings performed in the largest thermal powerplant (TE "Nikola Tesla B" are reffered and explained in this paper. The first calculation step is related to the coordination of the maximum stator current limiter settings, the overcurrent protection with inverse characteristics settings and the permitted overload of the generator stator B1. In the second calculation step the settings of impedance generator protection are determined, and the methods and criteria according to which the calculations are done are described. Criteria used to provide the protection to fulfill the backup protection role in the event of malfunction of the main protection of the transmission system. are clarified. The calculation of all protection functions (32 functions of generator B1 were performed in the project "Coordination of relay protection blocks B1 and B2 with the system of excitation and power system protections -TENT B".

  4. Reactor protection systems of 500 MWe PHWRs

    Energy Technology Data Exchange (ETDEWEB)

    Mallik, G; Kelkar, M G; Apte, Ravindra [C and I Group, Nuclear Power Corporation, Mumbai (India)

    1997-03-01

    The 500 MWe PHWR has two totally independent, diverse, fast acting shutdown system called Shutdown System 1 (SDS 1) and Shutdown System 2 (SDS 2). The trip generation circuitry of SDS 1 and SDS 2 are known as Reactor Protection System 1 (RPS 1) and Reactor Protection System 2 (RPS 2) respectively. Some of the features specific to 500 MWe reactors are Core Over Power Protection System (COPPS) based upon in core Self Powered Neutron Detector (SPND) signals, use of local two out of three coincidence logic and adoption of overlap testing for RPS 2, use of Fine Impulse Testing (FIT) in RPS 2, testing of the final control elements namely electro-magnetic clutch of individual Shutoff Rods (SRs) of SDS 1 and all the fast acting valves of SDS 2, etc. The two shutdown systems have totally separate sets of sensors and associated signal processing circuitry as well as physical arrangements. A separate computerised test and monitoring unit is used for each of the two shutdown systems. Use of Programmable Digital Comparator (PDC) unit exclusively for reactor protection systems, has been adopted. The capability of PDC unit is enhanced and communication links are provided for its integration in over all system. The paper describes the design features of reactor protection systems. (author). 3 refs., 7 figs., 3 tabs.

  5. High performing actuation system for use with a louver array for satellite thermal control. [design and performance tests on prototype Bourdon spiral configuration

    Science.gov (United States)

    Reusser, P. U.; Coebergh, J. A. F.

    1973-01-01

    A high performing actuation system has been developed to drive one pair or a set of 9 pairs of louver blades. The system uses a Bourdon spiral as the driving member. The response time of the liquid expansion of the spiral system is in the order of three seconds. Besides performance tests, qualification tests have been carried out on a prototype system, demonstrating that the actuation system withstands normal launching conditions; projected operating life of 7 years with more than 7000 cycles can be expected.

  6. Evolution of the radiation protection system; L'evolution du systeme de protection radiologique

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, R.H. [International Commission on Radiological Protection, Stockholm (Sweden); Schieber, C.; Cordoliani, Y.S. [Societe Francaise de Radioprotection, 92 - Fontenay aux Roses (France); Brechignac, F. [CEA Cadarache, Institut de Radioprotection et de Surete Nucleaire, Dept. de Protection de l' Environnement, 13 - Saint Paul Lez Durance (France)

    2003-07-01

    The evolution of the system of radiological protection: justification for new ICRP recommendations, thoughts of the SFRP work group about the evolution of the system of radiation protection proposed by the ICRP, protection of environment against ionizing radiations seen by the ICRP are the three parts of this chapter. (N.C.)

  7. Airplane Actuation Trade Study

    Science.gov (United States)

    1983-01-01

    Some of these advancements were high voltage power supplies, permanent magnet motors using rare earth magnets, electronic comnmutation and an...Essentially the inverter chops and pulse width modulates the 270 VDC power supplied by the electrical power system to cause the actuator’s permanent magnet motors to

  8. Adaptive Output Tracking Control for Nonlinear Systems with Failed Actuators and Aircraft Flight System Applications

    Directory of Open Access Journals (Sweden)

    Chuanjing Hou

    2015-01-01

    Full Text Available An adaptive failure compensation scheme using output feedback is proposed for a class of nonlinear systems with nonlinearities depending on the unmeasured states of systems. Adaptive high-gain K-filters are presented to suppress the nonlinearities while the proposed backstepping adaptive high-gain controller guarantees the stability of the closed-loop system and small tracking errors. Simulation results verify that the adaptive failure compensation scheme is effective.

  9. Adaptive Output Tracking Control for Nonlinear Systems with Failed Actuators and Aircraft Flight System Applications

    OpenAIRE

    Hou, Chuanjing; Hu, Lisheng; Zhang, Yingwei

    2015-01-01

    An adaptive failure compensation scheme using output feedback is proposed for a class of nonlinear systems with nonlinearities depending on the unmeasured states of systems. Adaptive high-gain K-filters are presented to suppress the nonlinearities while the proposed backstepping adaptive high-gain controller guarantees the stability of the closed-loop system and small tracking errors. Simulation results verify that the adaptive failure compensation scheme is effective.

  10. Protecting information in systems of systems

    NARCIS (Netherlands)

    Trivellato, D.

    2012-01-01

    Systems of systems are coalitions of autonomous and heterogeneous systems that collaborate to achieve a common goal. The component systems of a system of systems often belong to different security domains, which are governed by different authorities (hereafter called parties). Furthermore, systems

  11. Distribution system protection with communication technologies

    DEFF Research Database (Denmark)

    Wei, Mu; Chen, Zhe

    2010-01-01

    Due to the communication technologies’ involvement in the distribution power system, the time-critical protection function may be implemented more accurately, therefore distribution power systems’ stability, reliability and security could be improved. This paper presents an active distribution...

  12. Application of a hybrid modular acquisition system to the control of a suspended interferometer with electrostatic actuators

    Energy Technology Data Exchange (ETDEWEB)

    Acernese, F; Barone, F; Boiano, A; Rosa, R D; Garufi, F; Milano, L; Mosca, S; Persichetti, G; Romano, R [INFN - Sezione di Napoli, Complesso Universitario di Monte S. Angelo, via Cintia, 80126, Napoli (Italy); Perreca, A [University of Birmingham, Edgbaston, Birmingham, B15 2TT (United Kingdom)], E-mail: fabrizio.barone@na.infn.it

    2008-07-15

    In this paper we describe the architecture and the performances of a hybrid modular acquisition and control system prototype developed for the implementation of distributed monitoring and control systems. The system, an alternative to the VME-UDP/IP based system, is based on a dual-channel 18-bit low noise ADC and 16-bit DAC module at 800 kHz, managed by an ALTERA FPGA. Experimental tests have demonstrated that this architecture allows the implementation of distributed control systems with delay time t < 30{mu}s, on single channel, using a standard laptop PC for the real-time computation. The system was used for the longitudinal control of the end mirror of a suspended Michelson Interferometer, performed through an electrostatic actuators, giving effective performances. The preliminary results are also reported.

  13. Control rod blow out protection system

    International Nuclear Information System (INIS)

    Dietrich, J.R.; Flinn, W.S.; Groves, M.D.

    1979-01-01

    An absorber element blow-out protection system for a nuclear reactor having a pressure vessel through which a coolant is circulated. The blow-out protection system includes devices which hydraulically couple groups of guide tubes in which the absorber elements move, the coupling devices limiting coolant lift flow rate to a level commensurate with the raising of individual absorber elements but insufficient to raise a plurality of absorber elements simultaneously

  14. Machine Protection System response in 2011

    CERN Document Server

    Zerlauth, M; Wenninger, J

    2012-01-01

    The performance of the machine protection system during the 2011 run is summarized in this paper. Following an analysis of the beam dump causes in comparison to the previous 2010 run, special emphasis will be given to analyse events which risked to exposed parts of the machine to damage. Further improvements and mitigations of potential holes in the protection systems as well as in the change management will be evaluated along with their impact on the 2012 run. The role of the restricted Machine Protection Panel ( rMPP ) during the various operational phases such as commissioning, the intensity ramp up and Machine Developments is being discussed.

  15. Autonomous systems for plant protection

    DEFF Research Database (Denmark)

    Griepentrog, Hans W.; Ruckelhausen, Arno; Jørgensen, Rasmus N.

    2010-01-01

    Advances in automation are demanded by the market mainly as a response to high labor costs. Robotic outdoor systems are ready to allow not only economically viable operations but also increased efficiency in agriculture, horticulture and forestry. The aim of this chapter is to give examples of au...

  16. Physical protection system design and evaluation

    International Nuclear Information System (INIS)

    Williams, J.D.

    1997-11-01

    The design of an effective physical protection system (PPS) includes the determination of the PPS objectives, the initial design of a PPS, the evaluation of the design, and probably, the redesign or refinement of the system. To develop the objectives, the designer must begin by gathering information about facility operation and conditions, such as a comprehensive description of the facility, operating conditions, and the physical protection requirements. The designer then needs to define the threat. This involves considering factors about potential adversaries: class of adversary, adversary's capabilities, and range of adversary's tactics. Next, the designer should identify targets. Determination of whether or not the materials being protected are attractive targets is based mainly on the ease or difficulty of acquisition and desirability of the material. The designer now knows the objectives of the PPS, that is, ''what to protect against whom.'' The next step is to design the system by determining how best to combine such elements as fences, vaults, sensors and assessment devices, entry control devices, communication devices, procedures, and protective force personnel to meet the objectives of the system. Once a PPS is designed, it must be analyzed and evaluated to ensure it meets the PPS objectives. Evaluation must allow for features working together to ensure protection rather than regarding each feature separately. Due to the complexity of the protection systems, an evaluation usually requires modeling techniques. If any vulnerabilities are found, the initial system must be redesigned to correct the vulnerabilities and a reevaluation conducted. After the system is installed, the threat and system parameters may change with time. If they do, the analysis must be performed periodically to ensure the system objectives are still being met

  17. Human error probability evaluation as part of reliability analysis of digital protection system of advanced pressurized water reactor - APR 1400

    International Nuclear Information System (INIS)

    Varde, P. V.; Lee, D. Y.; Han, J. B.

    2003-03-01

    A case of study on human reliability analysis has been performed as part of reliability analysis of digital protection system of the reactor automatically actuates the shutdown system of the reactor when demanded. However, the safety analysis takes credit for operator action as a diverse mean for tripping the reactor for, though a low probability, ATWS scenario. Based on the available information two cases, viz., human error in tripping the reactor and calibration error for instrumentations in protection system, have been analyzed. Wherever applicable a parametric study has also been performed

  18. The APS machine protection system (MPS)

    International Nuclear Information System (INIS)

    Fuja, R.; Berg, B.; Arnold, N.

    1996-01-01

    The machine protection system (MPS) that protects the APS storage ring vacuum chamber from x-ray beams, is active. There are over 650 sensors monitored and networked through the MPS system. About the same number of other process variables are monitored by the much slower EPICS control system, which also has an input to the rf abort chain. The MPS network is still growing with the beam position limits detection system coming on-line. The network configuration, along with a limited description of individual subsystems, is presented

  19. The APS machine protection system (MPS)

    Energy Technology Data Exchange (ETDEWEB)

    Fuja, R.; Berg, B.; Arnold, N. [and others

    1996-08-01

    The machine protection system (MPS) that protects the APS storage ring vacuum chamber from x-ray beams, is active. There are over 650 sensors monitored and networked through the MPS system. About the same number of other process variables are monitored by the much slower EPICS control system, which also has an input to the rf abort chain. The MPS network is still growing with the beam position limits detection system coming on-line. The network configuration, along with a limited description of individual subsystems, is presented.

  20. Power system protection 1 principles and components

    CERN Document Server

    Association, Electricity Training

    1995-01-01

    The worldwide growth in demand for electricity has forced the pace of developments in electrical power system design to meet consumer needs for reliable, secure and cheap supplies. Power system protection, as a technology essential to high quality supply, is widely recognised as a specialism of growing and often critical importance, in which power system needs and technological progress have combined to result in rapid developments in policy and practice in recent years. In the United Kingdom, the need for appropriate training in power system protection was recognised in the early 1960s with t

  1. Distributed systems for protecting nuclear power stations

    International Nuclear Information System (INIS)

    Jover, P.

    1980-05-01

    The advantages of distributed control systems for the control of nuclear power stations are obviously of great interest. Some years ago, EPRI, (Electric Power Research Institute) showed that multiplexing the signals is technically feasible, that it enables the availability specifications to be met and costs to be reduced. Since then, many distributed control systems have been proposed by the manufacturers. This note offers some comments on the application of the distribution concept to protection systems -what should be distributed- and ends with a brief description of a protection system based on microprocessors for the pressurized power stations now being built in France [fr

  2. Pointwise Stabilization of a Hybrid System and Optimal Location of Actuator

    International Nuclear Information System (INIS)

    Ammari, Kais; Saidi, Abdelkader

    2007-01-01

    We consider a pointwise stabilization problem for a model arising in the control of noise. We prove that we have exponential stability for the low frequencies but not for the high frequencies. Thus, we give an explicit polynomial decay estimation at high frequencies that is valid for regular initial data while clarifying that the behavior of the constant which intervenes in this estimation there, functions as the frequency of cut. We propose a numerical approximation of the model and study numerically the best location of the actuator at low frequencies

  3. PCIe40 temperature protection system

    CERN Document Server

    Romero Aguilar, Angel

    2017-01-01

    PCIe40 is a high-throughput data-acquisition card based on PCI Express that is currently under development for the next upgrade of the LHCb experiment readout system. As part of this development, SMBus is intended to be used as a lightweight, out-of-band protocol to monitor the health of each data acquisition board. Starting from a simple prototype, the student will work on enabling SMBus communication between a COTS linux host and various on-board sensors, on top of existing linux facilities.

  4. Integration of Sensor and Actuator Networks and the SCADA System to Promote the Migration of the Legacy Flexible Manufacturing System towards the Industry 4.0 Concept

    Directory of Open Access Journals (Sweden)

    Antonio José Calderón Godoy

    2018-05-01

    Full Text Available Networks of sensors and actuators in automated manufacturing processes are implemented using industrial fieldbuses, where automation units and supervisory systems are also connected to exchange operational information. In the context of the incoming fourth industrial revolution, called Industry 4.0, the management of legacy facilities is a paramount issue to deal with. This paper presents a solution to enhance the connectivity of a legacy Flexible Manufacturing System, which constitutes the first step in the adoption of the Industry 4.0 concept. Such a system includes the fieldbus PROcess FIeld BUS (PROFIBUS around which sensors, actuators, and controllers are interconnected. In order to establish effective communication between the sensors and actuators network and a supervisory system, a hardware and software approach including Ethernet connectivity is implemented. This work is envisioned to contribute to the migration of legacy systems towards the challenging Industry 4.0 framework. The experimental results prove the proper operation of the FMS and the feasibility of the proposal.

  5. [Artificial intelligence] AI for protection systems

    Energy Technology Data Exchange (ETDEWEB)

    Aggarwal, R.; Johns, A.

    1997-12-31

    The reliable operation of large power systems with small stability margins is highly dependent on control systems and protection devices. Progress in the field of microprocessor systems and demanding requirements in respect of the performance of protective relays are the reasons for digital device applications to power system protection. The superiority of numeric protection over its analogue alternatives is attributed to such factors as accurate extraction of the fundamental voltage and current components through filtering, functional benefits resulting from multi-processor design and extensive self-monitoring, etc. However, all these reasons have not led to a major impact on speed, sensitivity and selectivity of primary protective relays, and the gains are only marginal; this is so because conventional digital relays still rely on deterministic signal models and a heuristic approach for decision making, so that only a fraction of the information contained within voltage and current signals as well as knowledge about the plant to be protected is used. The performance of digital relays may be substantially improved if the decision making is based on elements of artificial intelligence (AI). (Author)

  6. Protecting Information in Systems of Systems

    NARCIS (Netherlands)

    Trivellato, Daniel; Zannone, Nicola; Etalle, Sandro

    2011-01-01

    Systems of Systems (SoS) are dynamic, distributed coalitions of autonomous and heterogeneous systems that collaborate to achieve a common goal. While offering several advantages in terms of scalability and flexibility, the SoS paradigm has a strong impact on system interoperability and on the

  7. System Protection Schemes in Eastern Denmark

    DEFF Research Database (Denmark)

    Rasmussen, Joana

    outages in the southern part of the 132-kV system introduce further stress in the power system, eventually leading to a voltage collapse. The local System Protection Scheme against voltage collapse is designed as a response-based scheme, which is dependent on local indication of reactive and active power...... effective measures, because they are associated with large reactive power losses in the transmission system. Ordered reduction of wind generation is considered an effective measure to maintain voltage stability in the system. Reactive power in the system is released due to tripping of a significant amount...... system. In that way, the power system capability could be extended beyond normal limits....

  8. Nature-inspired microfluidic manipulation using magnetic actuators

    NARCIS (Netherlands)

    Khaderi, S. N.; Ioan, D.; den Toonder, J.M.J.; Onck, P. R.; LaVan, D.; Spearing, M.; Vengallatore, S.; DaSilva, M.

    2008-01-01

    Magnetically actuated micro-actuators are proposed to propel and manipulate fluid in micro-channels. As the fluid flows at low Reynolds number in such systems, the actuator should move in an asymmetric manner. The proposed actuators are polymer films with embedded magnetic particles, which are

  9. Advanced Protection & Service Restoration for FREEDM Systems

    Science.gov (United States)

    Singh, Urvir

    A smart electric power distribution system (FREEDM system) that incorporates DERs (Distributed Energy Resources), SSTs (Solid State Transformers - that can limit the fault current to two times of the rated current) & RSC (Reliable & Secure Communication) capabilities has been studied in this work in order to develop its appropriate protection & service restoration techniques. First, a solution is proposed that can make conventional protective devices be able to provide effective protection for FREEDM systems. Results show that although this scheme can provide required protection but it can be quite slow. Using the FREEDM system's communication capabilities, a communication assisted Overcurrent (O/C) protection scheme is proposed & results show that by using communication (blocking signals) very fast operating times are achieved thereby, mitigating the problem of conventional O/C scheme. Using the FREEDM System's DGI (Distributed Grid Intelligence) capability, an automated FLISR (Fault Location, Isolation & Service Restoration) scheme is proposed that is based on the concept of 'software agents' & uses lesser data (than conventional centralized approaches). Test results illustrated that this scheme is able to provide a global optimal system reconfiguration for service restoration.

  10. Power system EMP protection. Final report

    International Nuclear Information System (INIS)

    Marable, J.H.; Barnes, P.R.; Nelson, D.B.

    1975-05-01

    Voltage transients induced in electric power lines and control circuits by the electromagnetic pulse (EMP) from high-altitude nuclear detonations may cause widespread power failure and damage in electric power systems. This report contains a parametric study of EMP power line surges and discusses protective measures to minimize their effects. Since EMP surges have considerably greater rates of rise than lightning surges, recommended standards and test procedures are given to assure that surge arresters protect equipment from damage by EMP. Expected disturbances and damage to power systems are reviewed, and actions are presented which distribution companies can take to counter them. These include backup communications methods, stockpiling of vulnerable parts, repair procedures, and dispatcher actions to prevent blackout from EMP-caused instabilities. A long-range program is presented for improving distributors' protection against EMP. This involves employee training, hardware protection for power and control circuits, and improvement of plans for emergency action. (U.S.)

  11. A bidirectional shape memory alloy folding actuator

    International Nuclear Information System (INIS)

    Paik, Jamie K; Wood, Robert J

    2012-01-01

    This paper presents a low-profile bidirectional folding actuator based on annealed shape memory alloy sheets applicable for meso- and microscale systems. Despite the advantages of shape memory alloys—high strain, silent operation, and mechanical simplicity—their application is often limited to unidirectional operation. We present a bidirectional folding actuator that produces two opposing 180° motions. A laser-patterned nickel alloy (Inconel 600) heater localizes actuation to the folding sections. The actuator has a thin ( < 1 mm) profile, making it appropriate for use in robotic origami. Various design parameters and fabrication variants are described and experimentally explored in the actuator prototype. (paper)

  12. Actuators for smart applications

    NARCIS (Netherlands)

    Paternoster, Alexandre; de Boer, Andries; Loendersloot, Richard; Akkerman, Remko; D. Brei,; M. Frecker,

    2010-01-01

    Actuator manufacturers are developing promising technologies which meet high requirements in performance, weight and power consumption. Conventionally, actuators are characterized by their displacement and load performance. This hides the dynamic aspects of those actuation solutions. Work per weight

  13. Preliminary Evaluation of the Diverse Protection System in PGSFR

    International Nuclear Information System (INIS)

    Jeong, Taekyeong; Chang, Won-Pyo; Seong, Seung Hwan; Ahn, Sang June; Kang, Seok Hun; Choi, Chiwoong; Yoo, Jin; Lee, Kwi Lim; Lee, Seung Won; Jeong, Jae-Ho; Ha, Kwi-Seok

    2015-01-01

    The anticipated transient without scram (ATWS) is defined as an abnormal transient with failure of scram actuation. It is one of the “worst case” accident based on the United States Nuclear Regulatory Commission (U.S.NRC). Consideration frequently motivates the NRC to take regulatory action. An evaluation of this event is also a general requirement due to a potential safety issue that may lead to core damage under postulated condition. This paper estimated the set-points sensitivity test of the diverse protection system (DPS) related with unprotected events of the prototype generation-IV sodium cooled fast reactor (PGSFR) including unprotected transient over power (UTOP) and unprotected loss of flow (ULOF) by MARS-LMR code. The variation of the power to flow (P/Q) of UTOP and ULOF is illustrated to conduct the set-points sensitivity test of DPS. Also we estimated the effect of the DPS introduction after selecting UTOP, ULOF event as the unprotected events which are predicted to aggravate the events. This paper estimated the set-points sensitivity test of DPS related with unprotected events of PGSFR including UTOP and ULOF by MARS-LMR code. The results indicated that there is no significant difference in both RPS and DPS about the initiating time of each event. Therefore, this study found that the urgent manage for safety of the reactor when RPS failed is possible by the applying DPS

  14. Preliminary Evaluation of the Diverse Protection System in PGSFR

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Taekyeong; Chang, Won-Pyo; Seong, Seung Hwan; Ahn, Sang June; Kang, Seok Hun; Choi, Chiwoong; Yoo, Jin; Lee, Kwi Lim; Lee, Seung Won; Jeong, Jae-Ho; Ha, Kwi-Seok [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    The anticipated transient without scram (ATWS) is defined as an abnormal transient with failure of scram actuation. It is one of the “worst case” accident based on the United States Nuclear Regulatory Commission (U.S.NRC). Consideration frequently motivates the NRC to take regulatory action. An evaluation of this event is also a general requirement due to a potential safety issue that may lead to core damage under postulated condition. This paper estimated the set-points sensitivity test of the diverse protection system (DPS) related with unprotected events of the prototype generation-IV sodium cooled fast reactor (PGSFR) including unprotected transient over power (UTOP) and unprotected loss of flow (ULOF) by MARS-LMR code. The variation of the power to flow (P/Q) of UTOP and ULOF is illustrated to conduct the set-points sensitivity test of DPS. Also we estimated the effect of the DPS introduction after selecting UTOP, ULOF event as the unprotected events which are predicted to aggravate the events. This paper estimated the set-points sensitivity test of DPS related with unprotected events of PGSFR including UTOP and ULOF by MARS-LMR code. The results indicated that there is no significant difference in both RPS and DPS about the initiating time of each event. Therefore, this study found that the urgent manage for safety of the reactor when RPS failed is possible by the applying DPS.

  15. The protection system to Brazilian Nuclear Program

    International Nuclear Information System (INIS)

    Andreuzza, Mario Giussepp Santezzi Bertottelli

    1997-01-01

    The Sistema de Protecao ao Programa Nuclear Brasileiro-SIPRON (Protection System to Brazilian Nuclear Program) was established in 1980. It is intended to accomplish in only one system, all the actions related to security and protection for Nuclear Facilities in Brazil. The author presents in detail the protection system SIPRON, describing the system structure and organization, the functions and obligations of the system involved main organizations, as well as, the system operation and behaviour during an postulated occurrence of a nuclear emergency. It is also described an Exercise that happened in June of 1997 at the Nuclear Power Plant (NPP) Angra I, after two simulated tests in December of 1996 and April of 1997. The NPP Angra I Emergency Plan Exercise was a good opportunity to test the SIPRON structure and preparedness program. It was verified, included by International Atomic Energy Agency observers, the system involved organizations effectiveness and the procedures efficacy to protect the public and the environmental. Finally, it is shown the SIPRON activities of routine, the system obstacles and the expected future performances. (author)

  16. DLP-systems: Protection from Insiders

    Directory of Open Access Journals (Sweden)

    Ivan Sergeevich Boridko

    2013-02-01

    Full Text Available In the paper the necessity of further introduction of modern systems of information protection against internal leaks, including DLP-systems, is justified. The issues of development of training specialists in the field of information security is considered.

  17. Renovation of the cathodic protection system

    NARCIS (Netherlands)

    Schuten, G.; Leggedoor, J.; Polder, R.B.; Peelen, W.H.A.

    2003-01-01

    The first system for Cathodic Protection of concrete in the Netherlands was applied to a one bicycle lane of a bridge suffering corrosion due to de-icing salt penetration in 1986. This CP system was based on the Ferex 100S conducting polymer cable anode in a cementitious overlay. Its functioning was

  18. Future Interoperability of Camp Protection Systems (FICAPS)

    Science.gov (United States)

    Caron, Sylvie; Gündisch, Rainer; Marchand, Alain; Stahl, Karl-Hermann

    2013-05-01

    The FICAPS Project has been established as a Project of the European Defence Agency based on an initiative of Germany and France. Goal of this Project was to derive Guidelines, which by a proper implementation in future developments improve Camp Protection Systems (CPS) by enabling and improving interoperability between Camp Protection Systems and its Equipments of different Nations involved in multinational missions. These Guidelines shall allow for: • Real-time information exchange between equipments and systems of different suppliers and nations (even via SatCom), • Quick and easy replacement of equipments (even of different Nations) at run-time in the field by means of plug and play capability, thus lowering the operational and logistic costs and making the system highly available, • Enhancement of system capabilities (open and modular systems) by adding new equipment with new capabilities (just plug-in, automatic adjustment of the HMI Human Machine Interface) without costly and time consuming validation and test on system level (validation and test can be done on Equipment level), Four scenarios have been identified to summarize the interoperability requirements from an operational viewpoint. To prove the definitions given in the Guideline Document, a French and a German Demonstration System, based on existing national assets, were realized. Demonstrations, showing the capabilities given by the defined interoperability requirements with respect to the operational scenarios, were performed. Demonstrations included remote control of a CPS by another CPS, remote sensor control (Electro-Optic/InfraRed EO/IR) and remote effector control. This capability can be applied to extend the protection area or to protect distant infrastructural assets Demonstrations have been performed. The required interoperability functionality was shown successfully. Even if the focus of the FICAPS project was on camp protection, the solution found is also appropriate for other

  19. Management information system on radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Grossi, Pablo Andrade; Souza, Leonardo Soares de; Figueiredo, Geraldo Magela, E-mail: pabloag@cdtn.b, E-mail: lss@cdtn.b, E-mail: gmf@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    Considering the flux complexity and the multi source information of all radiation protection activities on nuclear organizations, an effective management information system based on technology, information and people is necessary to improve the safety on all processes and operations subjected to radiation risks. An effective management information system is an essential tool to highlight the strengths and weaknesses and identify behaviors and trends on the activities requiring radiation protection programs. Such kind of distinct knowledge is useful to reach an effective management and support the human decision-making on nuclear organization. This paper presents a management information system based on Brazilian directives and regulations on radiation protection. Due to its generic characteristics, this radiation protection control system can be implemented on any nuclear organization by reediting the non restricted parameters which could differ considering all facilities and laboratories expected on-site with diverse technologies applications. This system can be considered as a powerful tool applied on the continuous management of radiation protection activities on nuclear organizations and research institutes as well as for long term planning, not only indicating how the safety activities are going, but why they are not going as well as planned where that is the case. (author)

  20. Management information system on radiation protection

    International Nuclear Information System (INIS)

    Grossi, Pablo Andrade; Souza, Leonardo Soares de; Figueiredo, Geraldo Magela

    2011-01-01

    Considering the flux complexity and the multi source information of all radiation protection activities on nuclear organizations, an effective management information system based on technology, information and people is necessary to improve the safety on all processes and operations subjected to radiation risks. An effective management information system is an essential tool to highlight the strengths and weaknesses and identify behaviors and trends on the activities requiring radiation protection programs. Such kind of distinct knowledge is useful to reach an effective management and support the human decision-making on nuclear organization. This paper presents a management information system based on Brazilian directives and regulations on radiation protection. Due to its generic characteristics, this radiation protection control system can be implemented on any nuclear organization by reediting the non restricted parameters which could differ considering all facilities and laboratories expected on-site with diverse technologies applications. This system can be considered as a powerful tool applied on the continuous management of radiation protection activities on nuclear organizations and research institutes as well as for long term planning, not only indicating how the safety activities are going, but why they are not going as well as planned where that is the case. (author)

  1. PID position regulation in one-degree-of-freedom Euler-Lagrange systems actuated by a PMSM

    Science.gov (United States)

    Verastegui-Galván, J.; Hernández-Guzmán, V. M.; Orrante-Sakanassi, J.

    2018-02-01

    This paper is concerned with position regulation in one-degree-of-freedom Euler-Lagrange Systems. We consider that the mechanical subsystem is actuated by a permanent magnet synchronous motor (PMSM). Our proposal consists of a Proportional-Integral-Derivative (PID) controller for the mechanical subsystem and a slight variation of field oriented control for the PMSM. We take into account the motor electric dynamics during the stability analysis. We present, for the first time, a global asymptotic stability proof for such a control scheme without requiring the mechanical subsystem to naturally possess viscous friction. Finally, as a corollary of our main result we prove global asymptotic stability for output feedback PID regulation of one-degree-of-freedom Euler-Lagrange systems when generated torque is considered as the system input, i.e. when the electric dynamics of PMSM's is not taken into account.

  2. Influence of a Crosslinker Containing an Azo Group on the Actuation Properties of a Photoactuating LCE System

    Directory of Open Access Journals (Sweden)

    Lukas B. Braun

    2016-12-01

    Full Text Available Photoactuating liquid crystalline elastomers (LCE are promising candidates for an application as artificial muscles in microdevices. In this work, we demonstrate that by optimizing (1 the illumination conditions and (2 the mixture of azo monomer and azo crosslinker, thick films of an all-azo LCE can be prepared, which show a strong length change without bending during photoactuation. This becomes possible by working with white light (about 440 nm, whose absorption is low, leading to a large penetration depth. By adding an azo crosslinker to a previously prepared system, several improvements of the actuation properties—like a stronger photoactuation at lower operational temperatures—could be achieved. In addition, films of different crosslinker concentrations and thicknesses were produced by photopolymerization at varying temperatures within a magnetic field, and their thermo- and photoresponsive behavior was investigated. An extraordinarily strong maximal thermal actuation of 46% and—by exposure to white light at 70 °C—a photoresponsive change in length of up to 40% in just about 13 s could be obtained. Even densely crosslinked samples were still able to photoactuate remarkably. Isothermal back-deformation could either be achieved by irradiation with red light (7 min or by keeping the film in the dark (13 min.

  3. Rate dependent direct inverse hysteresis compensation of piezoelectric micro-actuator used in dual-stage hard disk drive head positioning system.

    Science.gov (United States)

    Rahman, Md Arifur; Al Mamun, Abdullah; Yao, Kui

    2015-08-01

    The head positioning servo system in hard disk drive is implemented nowadays using a dual-stage actuator—the primary stage consisting of a voice coil motor actuator providing long range motion and the secondary stage controlling the position of the read/write head with fine resolution. Piezoelectric micro-actuator made of lead zirconate titanate (PZT) has been a popular choice for the secondary stage. However, PZT micro-actuator exhibits hysteresis—an inherent nonlinear characteristic of piezoelectric material. The advantage expected from using the secondary micro-actuator is somewhat lost by the hysteresis of the micro-actuator that contributes to tracking error. Hysteresis nonlinearity adversely affects the performance and, if not compensated, may cause inaccuracy and oscillation in the response. Compensation of hysteresis is therefore an important aspect for designing head-positioning servo system. This paper presents a new rate dependent model of hysteresis along with rigorous analysis and identification of the model. Parameters of the model are found using particle swarm optimization. Direct inverse of the proposed rate-dependent generalized Prandtl-Ishlinskii model is used as the hysteresis compensator. Effectiveness of the overall solution is underscored through experimental results.

  4. Polypyrrole Actuators for Tremor Suppression

    DEFF Research Database (Denmark)

    Skaarup, Steen; Mogensen, Naja; Bay, Lasse

    2003-01-01

    Neurological tremor affecting limbs can be divided into at least 6 different types with frequencies ranging from 2 to about 20 Hz. In order to alleviate the symptoms by suppressing the tremor, sensing and actuation systems able to perform at these frequencies are needed. Electroactive polymers...... exemplify 'soft actuator' technology that may be especially suitable for use in conjunction with human limbs. The electrochemical and mechanical properties of polypyrrole dodecyl benzene sulphonate actuator films have been studied with this application in mind. The results show that the time constants...

  5. Electrical Actuation Technology Bridging

    Science.gov (United States)

    Hammond, Monica (Compiler); Sharkey, John (Compiler)

    1993-01-01

    This document contains the proceedings of the NASA Electrical Actuation Technology Bridging (ELA-TB) Workshop held in Huntsville, Alabama, September 29-October 1, 1992. The workshop was sponsored by the NASA Office of Space Systems Development and Marshall Space Flight Center (MSFC). The workshop addressed key technologies bridging the entire field of electrical actuation including systems methodology, control electronics, power source systems, reliability, maintainability, and vehicle health management with special emphasis on thrust vector control (TVC) applications on NASA launch vehicles. Speakers were drawn primarily from industry with participation from universities and government. In addition, prototype hardware demonstrations were held at the MSFC Propulsion Laboratory each afternoon. Splinter sessions held on the final day afforded the opportunity to discuss key issues and to provide overall recommendations. Presentations are included in this document.

  6. Televison assessment and identification system for the plutonium protection system

    International Nuclear Information System (INIS)

    Greenwoll, D.A.

    1979-02-01

    This report covers the selection, description, and use of the components comprising the Television Assessment and Identification System in the Hanford Plutonium Protection System. This work was sponsored by the Department of Energy/Office of Safeguards and Security (DOE/OSS) as part of the overall Sandia Fixed Facility Physical Protection Program

  7. Distance Protection for Microgrids in Distribution System

    DEFF Research Database (Denmark)

    Lin, Hengwei; Liu, Chengxi; Guerrero, Josep M.

    2015-01-01

    protection decreased. This paper adopts distance protection for one mid-voltage level microgrid in Aalborg, Denmark. Different operation modes of the network are analyzed and tested in the paper. The simulation results show that the variations of the fault currents seen by the forward relays are much larger...... than the backward relays. Meanwhile, the fault currents change little with the randomness of renewable energy except the intermittence. Finally, it shows that the designed distance protection has satisfactory performance to clear the various faults.......Owing to the increasing penetration of distributed generation, there are some challenges for the conventional protection in distribution system. Bidirectional power flow and variable fault current because of the various operation modes may lead to the selectivity and sensitivity of the overcurrent...

  8. A Reconfiguration Scheme for Accommodating Actuator Failures in Multi-Input, Multi-Output Flight Control Systems

    Science.gov (United States)

    Siwakosit, W.; Hess, R. A.; Bacon, Bart (Technical Monitor); Burken, John (Technical Monitor)

    2000-01-01

    A multi-input, multi-output reconfigurable flight control system design utilizing a robust controller and an adaptive filter is presented. The robust control design consists of a reduced-order, linear dynamic inversion controller with an outer-loop compensation matrix derived from Quantitative Feedback Theory (QFT). A principle feature of the scheme is placement of the adaptive filter in series with the QFT compensator thus exploiting the inherent robustness of the nominal flight control system in the presence of plant uncertainties. An example of the scheme is presented in a pilot-in-the-loop computer simulation using a simplified model of the lateral-directional dynamics of the NASA F18 High Angle of Attack Research Vehicle (HARV) that included nonlinear anti-wind up logic and actuator limitations. Prediction of handling qualities and pilot-induced oscillation tendencies in the presence of these nonlinearities is included in the example.

  9. Improved control for distributed parameter systems with time-dependent spatial domains utilizing mobile sensor–actuator networks

    International Nuclear Information System (INIS)

    Zhang Jian-Zhong; Cui Bao-Tong; Zhuang Bo

    2017-01-01

    A guidance policy for controller performance enhancement utilizing mobile sensor–actuator networks (MSANs) is proposed for a class of distributed parameter systems (DPSs), which are governed by diffusion partial differential equations (PDEs) with time-dependent spatial domains. Several sufficient conditions for controller performance enhancement are presented. First, the infinite dimensional operator theory is used to derive an abstract evolution equation of the systems under some rational assumptions on the operators, and a static output feedback controller is designed to control the spatial process. Then, based on Lyapunov stability arguments, guidance policies for collocated and non-collocated MSANs are provided to enhance the performance of the proposed controller, which show that the time-dependent characteristic of the spatial domains can significantly affect the design of the mobile scheme. Finally, a simulation example illustrates the effectiveness of the proposed policy. (paper)

  10. Dependability Evaluation of Advanced Diverse Protection System

    International Nuclear Information System (INIS)

    Oh, Yang Gyun; Lee, Yoon Hee; Sohn, Se Do; Baek, Seung Min; Lee, Sang Jeong

    2014-01-01

    For the mitigation of anticipated transients without scram (ATWS) as well as common cause failure (CCF) within the plant protection system (PPS) and the emergency safety feature . component control system (ESF-CCS), the diverse protection system (DPS) has been designed by KEPCO Engineering and Construction Company. Recently KEPCO E and C has developed the advanced diverse protection system (ADPS), which has four redundant channels, in an attempt to enhance a fault-tolerant capability of the system. For the evaluation of overall system improvement effects of the ADPS compared with the DPS, the dependability evaluation results are described herein. For all dependability attributes, this paper suggests a practical dependability evaluation method which uses quantitative dependability scores and indices. An overall dependability evaluation index (DEI) for the ADPS is evaluated with the average value of reliability/ security/maintainability/safety indices (i.e., RID, SID, MID, and SID') for dependability. The evaluation results show that the DEI value of ADPS can be improved by approximately 23% compared with that of the DPS, thanks to its fault-tolerant system architecture, software design changes, and external interface design features. Several suggestions have been made, in this paper, of an overall quantitative dependability evaluation method for the nuclear instrumentation and control (I and C) systems including the DPS and ADPS, and the usefulness of dependability evaluation on nuclear I and C systems has been confirmed

  11. Adaptive Neural Networks Decentralized FTC Design for Nonstrict-Feedback Nonlinear Interconnected Large-Scale Systems Against Actuator Faults.

    Science.gov (United States)

    Li, Yongming; Tong, Shaocheng

    The problem of active fault-tolerant control (FTC) is investigated for the large-scale nonlinear systems in nonstrict-feedback form. The nonstrict-feedback nonlinear systems considered in this paper consist of unstructured uncertainties, unmeasured states, unknown interconnected terms, and actuator faults (e.g., bias fault and gain fault). A state observer is designed to solve the unmeasurable state problem. Neural networks (NNs) are used to identify the unknown lumped nonlinear functions so that the problems of unstructured uncertainties and unknown interconnected terms can be solved. By combining the adaptive backstepping design principle with the combination Nussbaum gain function property, a novel NN adaptive output-feedback FTC approach is developed. The proposed FTC controller can guarantee that all signals in all subsystems are bounded, and the tracking errors for each subsystem converge to a small neighborhood of zero. Finally, numerical results of practical examples are presented to further demonstrate the effectiveness of the proposed control strategy.The problem of active fault-tolerant control (FTC) is investigated for the large-scale nonlinear systems in nonstrict-feedback form. The nonstrict-feedback nonlinear systems considered in this paper consist of unstructured uncertainties, unmeasured states, unknown interconnected terms, and actuator faults (e.g., bias fault and gain fault). A state observer is designed to solve the unmeasurable state problem. Neural networks (NNs) are used to identify the unknown lumped nonlinear functions so that the problems of unstructured uncertainties and unknown interconnected terms can be solved. By combining the adaptive backstepping design principle with the combination Nussbaum gain function property, a novel NN adaptive output-feedback FTC approach is developed. The proposed FTC controller can guarantee that all signals in all subsystems are bounded, and the tracking errors for each subsystem converge to a small

  12. Assessment of physical protection systems: EVA method

    International Nuclear Information System (INIS)

    Bernard, J.-L.; Lamotte, C.; Jorda, A.

    2001-01-01

    CEA's missions in various sectors of activity such as nuclear, defence, industrial contracts and the associated regulatory requirements, make it necessary to develop a strategy in the field of physical protection. In particular, firms having nuclear materials are subject to the July 25, 1980 law no.80-572 on the protection and control of nuclear materials. A holding permit delivered by the regulatory authority is conditioned to the protection by the operator of the nuclear materials used. In France it is the nuclear operator who must demonstrate, in the form of a security study, that potential aggressors would be neutralised before they could escape with the material. To meet these requirements, we have developed methods to assess the vulnerability of our facilities. The EVA method, the French acronym for 'Evaluation de la vulnerabilite des Acces' (access vulnerability system) allows dealing with internal and external threats involving brutal actions. In scenarios relating to external threat, the intruders get past the various barriers of our protection system, attempting to steal a large volume of material in one swoop and then escape. In the case of internal threat, the goal is the same. However, as the intruder usually has access to the material in the scope of his activities, the action begins at the level of the target. Our protection system is based on in-depth defense where the intruders are detected and then delayed in their advance towards their target to allow time for intervention forces to intercept them

  13. Evolution of the system of radiological protection

    International Nuclear Information System (INIS)

    2005-11-01

    One of the main challenges facing radiological protection experts is how to integrate radiological protection within modern concepts of and approaches to risk governance. It is within this context that the International Commission on Radiological Protection (ICRP) decided to develop new general recommendations to replace its Publication 60 recommendations of 1990. In the process of developing these new recommendations, the views of the ICRP have evolved significantly, largely due to stakeholder involvement that has been actively solicited by the ICRP. In this regard, it was upheld during the First Asian Regional Conference organised by the NEA in October 2002 that the implementation of the new system must allow for regional, societal and cultural differences. In order to ensure appropriate consideration of these differences, the NEA organised the Second Asian Regional Conference on the Evolution of the System of Radiological Protection. Held in Tokyo on 28-29 July 2004, the conference included presentations by the ICRP Chair as well as by radiological experts from Australia, China, Japan and Korea. Within their specific cultural and socio-political milieu, Asia-Pacific and western ways of thought on how to improve the current system of radiological protection were presented and discussed. These ways of thinking, along with a summary of the conference results, are described in these proceedings. (author)

  14. Application of fault tree methodology to modeling of the AP1000 plant digital reactor protection system

    International Nuclear Information System (INIS)

    Teolis, D.S.; Zarewczynski, S.A.; Detar, H.L.

    2012-01-01

    The reactor trip system (RTS) and engineered safety features actuation system (ESFAS) in nuclear power plants utilizes instrumentation and control (IC) to provide automatic protection against unsafe and improper reactor operation during steady-state and transient power operations. During normal operating conditions, various plant parameters are continuously monitored to assure that the plant is operating in a safe state. In response to deviations of these parameters from pre-determined set points, the protection system will initiate actions required to maintain the reactor in a safe state. These actions may include shutting down the reactor by opening the reactor trip breakers and actuation of safety equipment based on the situation. The RTS and ESFAS are represented in probabilistic risk assessments (PRAs) to reflect the impact of their contribution to core damage frequency (CDF). The reactor protection systems (RPS) in existing nuclear power plants are generally analog based and there is general consensus within the PRA community on fault tree modeling of these systems. In new plants, such as AP1000 plant, the RPS is based on digital technology. Digital systems are more complex combinations of hardware components and software. This combination of complex hardware and software can result in the presence of faults and failure modes unique to a digital RPS. The United States Nuclear Regulatory Commission (NRC) is currently performing research on the development of probabilistic models for digital systems for inclusion in PRAs; however, no consensus methodology exists at this time. Westinghouse is currently updating the AP1000 plant PRA to support initial operation of plants currently under construction in the United States. The digital RPS is modeled using fault tree methodology similar to that used for analog based systems. This paper presents high level descriptions of a typical analog based RPS and of the AP1000 plant digital RPS. Application of current fault

  15. An integrated numerical protection system (SPIN)

    International Nuclear Information System (INIS)

    Savornin, J.L.; Bouchet, J.M.; Furet, J.L.; Jover, P.; Sala, A.

    1978-01-01

    Developments in technology have now made it possible to perform more sophisticated protection functions which follow more closely the physical phenomena to be monitored. For this reason the Commissariat a l'energie atomique, Merlin-Gerin, Cerci and Framatome have embarked on the joint development of an Integrated Numerical Protection System (SPIN) which will fulfil this objective and will improve the safety and availability of power stations. The system described involves the use of programmed numerical techniques and a structure based on multiprocessors. The architecture has a redundancy of four. Throughout the development of the project the validity of the studies was confirmed by experiments. A first numerical model of a protection function was tested in the laboratory and is now in operation in a power station. A set of models was then introduced for checking the main components of the equipment finally chosen prior to building and testing a prototype. (author)

  16. Evolution of the system of radiological protection

    International Nuclear Information System (INIS)

    2004-01-01

    The development of new radiological protection recommendations by the International Commission on Radiological Protection (ICRP) continues to be a strategically important undertaking, both nationally and internationally. With the growing recognition of the importance of stakeholder aspects in radiological protection decision making, regional and cultural aspects have also emerged as having potentially significant influence on how protection of the public, workers and the environment are viewed. Differing cultural aspects should therefore be considered by the ICRP in its development of new recommendations. Based on this assumption, the NEA organised the Asian Regional Conference on the Evolution of the System of Radiological Protection to express and explore views from the Far East. Held in Tokyo on 24-25 October 2002, the conference included presentations by the ICRP Chair as well as by radiological protection experts from Japan, the Republic of Korea, China and Australia. The distinct views and needs of these countries were discussed in the context of their regional and cultural heritages. These views, along with a summary of the conference results, are presented in these proceedings. (author)

  17. 78 FR 77574 - Protection System Maintenance Reliability Standard

    Science.gov (United States)

    2013-12-24

    ... commissioning of power system protection systems.\\55\\ NERC commits in its Comments to keep the Commission... commissioning of power system protection systems.\\62\\ As explained in the NOPR, our concern is with a protection... protection system, ``resulting in line relays being placed in service with the incorrect transformer ratio...

  18. Compact, planar, translational piezoelectric bimorph actuator with Archimedes’ spiral actuating tethers

    International Nuclear Information System (INIS)

    Yang, Chenye; Liu, Sanwei; Livermore, Carol; Xie, Xin

    2016-01-01

    The design, analytical modelling, finite element analysis (FEA), and experimental characterization of a microelectromechanical system (MEMS) out-of-plane (vertical) translational piezoelectric lead–zirconate–titanate (PZT) bimorph actuator supported on Archimedes’ spiral tethers are presented. Three types of bimorph actuators with different electrode patterns (with spiral tethers half actuated, fully actuated with uniform polarity, or fully actuated with reversed polarity) are designed and modelled. The two actuators with the highest predicted performance (half actuated and fully actuated with uniform polarity) are implemented and characterized. Both designs are fabricated by commercial processes and are compatible with integration into more complex MEMS systems. Analytical modelling and FEA are used to analyze and predict the actuators’ displacements and blocking forces. Experimental measurements of the deflections and blocking forces of actuators with full uniform actuation and half actuation validate the design. At an applied voltage of 110 V, the out-of-plane deflections of the actuators with half actuation and full uniform actuation are measured at about 17 µ m and 29 µ m respectively, in good agreement with analytical predictions of 17.3 µ m and 34.2 µ m and FEA predictions of 17.1 µ m and 25.8 µ m. The blocking force for devices with half-actuated tethers is predicted to be 12 mN (analytical) and 10 mN (FEA), close to the experimental value of 9 mN. The blocking force for devices with full uniform actuation is predicted to be 23 mN (analytical) and 17 mN (FEA), as compared with 15 mN in experiments. (paper)

  19. A microfluidic control system with re-usable micropump/valve actuator and injection moulded disposable polymer lab-on-a-slide

    DEFF Research Database (Denmark)

    Bu, Minqiang; Perch-Nielsen, Ivan R.; Yi, Sun

    2011-01-01

    A microfluidic control system consisting of micropump/valves with a re-usable pneumatic actuator and a disposable polymer lab-on-a-slide is presented. The lab-on-a-slide was fabricated using low cost methods, such as injection moulding of TOPAS® cyclic olefin copolymer (COC) slide, lamination...... of different layers of polymer, and ultrasonic welding of TOPAS® lid to the slide. The re-usable pneumatic actuator not only simplifies the design of the lab-on-a-slide and reduces the fabrication cost, but also reduces the possibility of cross contamination during replacement of the disposable lab...

  20. Additional reactor protection system of RBMK-1500

    International Nuclear Information System (INIS)

    1999-01-01

    Analysis of anticipated transients without scram of RBMK-1500 reactor showed that additional reactor protection system is required. Data of accident analysis in the case of loose of external electric power and loose of vacuum in condensers of turbines are provided

  1. Validation of reactor core protection system

    International Nuclear Information System (INIS)

    Lee, Sang-Hoon; Bae, Jong-Sik; Baeg, Seung-Yeob; Cho, Chang-Ho; Kim, Chang-Ho; Kim, Sung-Ho; Kim, Hang-Bae; In, Wang-Kee; Park, Young-Ho

    2008-01-01

    Reactor COre Protection System (RCOPS), an advanced core protection calculator system, is a digitized one which provides core protection function based on two reactor core operation parameters, Departure from Nucleate Boiling Ratio (DNBR) and Local Power Density (LPD). It generates a reactor trip signal when the core condition exceeds the DNBR or LPD design limit. It consists of four independent channels adapted a two-out-of-four trip logic. System configuration, hardware platform and an improved algorithm of the newly designed core protection calculator system are described in this paper. One channel of RCOPS was implemented as a single channel facility for this R and D project where we performed final integration software testing. To implement custom function blocks, pSET is used. Software test is performed by two methods. The first method is a 'Software Module Test' and the second method is a 'Software Unit Test'. New features include improvement of core thermal margin through a revised on-line DNBR algorithm, resolution of the latching problem of control element assembly signal and addition of the pre-trip alarm generation. The change of the on-line DNBR calculation algorithm is considered to improve the DNBR net margin by 2.5%-3.3%. (author)

  2. Development of a 3D parallel mechanism robot arm with three vertical-axial pneumatic actuators combined with a stereo vision system.

    Science.gov (United States)

    Chiang, Mao-Hsiung; Lin, Hao-Ting

    2011-01-01

    This study aimed to develop a novel 3D parallel mechanism robot driven by three vertical-axial pneumatic actuators with a stereo vision system for path tracking control. The mechanical system and the control system are the primary novel parts for developing a 3D parallel mechanism robot. In the mechanical system, a 3D parallel mechanism robot contains three serial chains, a fixed base, a movable platform and a pneumatic servo system. The parallel mechanism are designed and analyzed first for realizing a 3D motion in the X-Y-Z coordinate system of the robot's end-effector. The inverse kinematics and the forward kinematics of the parallel mechanism robot are investigated by using the Denavit-Hartenberg notation (D-H notation) coordinate system. The pneumatic actuators in the three vertical motion axes are modeled. In the control system, the Fourier series-based adaptive sliding-mode controller with H(∞) tracking performance is used to design the path tracking controllers of the three vertical servo pneumatic actuators for realizing 3D path tracking control of the end-effector. Three optical linear scales are used to measure the position of the three pneumatic actuators. The 3D position of the end-effector is then calculated from the measuring position of the three pneumatic actuators by means of the kinematics. However, the calculated 3D position of the end-effector cannot consider the manufacturing and assembly tolerance of the joints and the parallel mechanism so that errors between the actual position and the calculated 3D position of the end-effector exist. In order to improve this situation, sensor collaboration is developed in this paper. A stereo vision system is used to collaborate with the three position sensors of the pneumatic actuators. The stereo vision system combining two CCD serves to measure the actual 3D position of the end-effector and calibrate the error between the actual and the calculated 3D position of the end-effector. Furthermore, to

  3. New evaluation system for antisabotage physical protection

    International Nuclear Information System (INIS)

    Itakura, Shuichiro; Nakagome, Yoshihiro

    2008-01-01

    The discussion on an appropriate level of physical protection has not been elaborated so far because of the confidentiality of its nature, thus resulting in a lack of consensus on this issue. In view of this context, a new system for the evaluation of antisabotage physical protection systems is proposed in this paper, in which we introduce openness to a certain extent in the process of the evaluation. The proposed system is composed of the following three elements; (1) establishment of an evaluation basis threat (EBT), which should be less strong but more likely to occur than the design basis threat (DBT); (2) employment of realistic standard scenarios in the process of evaluation; (3) disclosure of results of evaluation implemented based on the above EBT and standard scenarios. It is expected that this considerably open system will foment peace of mind among citizens as well as create a deterrent effect that would minimize the occurrence of sabotage on nuclear facilities. (author)

  4. Safety Analysis for Power Reactor Protection System

    International Nuclear Information System (INIS)

    Eisawy, E.A.; Sallam, H.

    2012-01-01

    The main function of a Reactor Protection System (RPS) is to safely shutdown the reactor and prevents the release of radioactive materials. The purpose of this paper is to present a technique and its application for used in the analysis of safety system of the Nuclear Power Plant (NPP). A more advanced technique has been presented to accurately study such problems as the plant availability assessments and Technical Specifications evaluations that are becoming increasingly important. The paper provides the Markov model for the Reactor Protection System of the NPP and presents results of model evaluations for two testing policies in technical specifications. The quantification of the Markov model provides the probability values that the system will occupy each of the possible states as a function of time.

  5. Control of Adjustable Compliant Actuators

    Directory of Open Access Journals (Sweden)

    Berno J.E. Misgeld

    2014-05-01

    Full Text Available Adjustable compliance or variable stiffness actuators comprise an additional element to elastically decouple the actuator from the load and are increasingly applied to human-centered robotic systems. The advantages of such actuators are of paramount importance in rehabilitation robotics, where requirements demand safe interaction between the therapy system and the patient. Compliant actuator systems enable the minimization of large contact forces arising, for example, from muscular spasticity and have the ability to periodically store and release energy in cyclic movements. In order to overcome the loss of bandwidth introduced by the elastic element and to guarantee a higher range in force/torque generation, new actuator designs consider variable or nonlinear stiffness elements, respectively. These components cannot only be adapted to the walking speed or the patient condition, but also entail additional challenges for feedback control. This paper introduces a novel design method for an impedance-based controller that fulfills the control objectives and compares the performance and robustness to a classical cascaded control approach. The new procedure is developed using a non-standard positive-real Η2 controller design and is applied to a loop-shaping approach. Robust norm optimal controllers are designed with regard to the passivity of the actuator load-impedance transfer function and the servo control problem. Classical cascaded and positive-real Η2 controller designs are validated and compared in simulations and in a test bench using a passive elastic element of varying stiffness.

  6. Structural integrity and failure mechanisms of a smart piezoelectric actuator under a cyclic bending mode

    International Nuclear Information System (INIS)

    Woo, Sung-Choong; Goo, Nam Seo

    2008-01-01

    Information on the onset and evolution of damage within materials is essential for guaranteeing the integrity of actuator systems. The authors have evaluated the structural integrity and the failure mechanisms of smart composite actuators with a PZT ceramic plate under electric cyclic loading. For this, two kinds of actuators, actuator 1 and actuator 2, were manufactured. Prior to the main testing, performance testing was performed on the actuators to determine their resonant frequencies. Electric cyclic tests were conducted up to twenty million cycles. An acoustic emission technique was used for monitoring the damage evolution in real time. We observed the extent of the damage after testing using scanning electron microscopy and reflected optical microscopy to support characteristics in the acoustic emission behavior that corresponded to specific types of damage mechanisms. It was shown that the initial damage mechanism of the smart composite actuator under electric cyclic loading originated from the transgranular micro-fatigue damage in the PZT ceramic layer. With increasing cycles, a local intergranular crack initiated and developed onto the surface of the PZT ceramic layer or propagated into the internal layer. Finally, short-circuiting led to the electric breakdown of the actuator. These results were different depending on the drive frequencies and the configuration of the actuators. Moreover, we differentiated between the aforementioned damage mechanisms via AE signal pattern analyses based on the primary frequency and the waveform. From our results, we conclude that the drive frequency and the existence of a protecting layer are dominant factors in the structural integrity of the smart composite actuator

  7. Regulatory System of Radiation Protection in Taiwan

    International Nuclear Information System (INIS)

    Tang, F. T.; Huang, C. C.

    2004-01-01

    After the radioactive contaminated buildings incident occurred in Taiwan in 1993, the competent authority for radiation protection the Atomic Energy Council (AEC) started to review the structured problem of radiation protection regulatory system. Through several years' investigation and study, the AEC has improved two important tools in radiation protection regulatory system, i.e., control regulations and actual practice, and made them more rigorous and efficient. This paper will make a brief introduction of the efforts that Taiwan has made in this respect. Taiwan's radiation protection control was based on the Atomic Energy Law promulgated in 1968, but the control idea and authorization scope were not sufficient to appropriately respond to the highly developed economy and democracy in Taiwan. After several years' legislative process, the Ionizing Radiation Protection Law (IRP Law) was promulgated and entered into force on February 1, 2003. This IRP Law specifically emphasizes categorized risk management of radiation sources, establishment of personnel licenses and training system, enhancement of public safety control, and implementation of quality assurance program for medical exposure. The Legislative Yuan (Congress) fully authorized the competent authority to establish various technological control regulations according to control necessity without prior review by the Legislative Yuan in advance. As to the penalties of the violations of the IRP Law, the AEC adopts high-rated administrative fines and applies the Criminal Law to those who seriously contaminate the environment. In actual practice, the AEC has constructed a Radiation Protection Control Information System compatible with the IRP Law that fully combines the functions of computers and Internet. The information of facility operators who own radiation sources, radiation protection specialists, and operating personnel are entered into this system, starting from the submission of application of the

  8. Addressing Circuitous Currents MVDC Power Systems Protection

    Science.gov (United States)

    2017-12-31

    Addressing Circuitous Currents MVDC Power Systems Protection 5b. GRANT NUMBER N00014-16-1-3113 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR($) Sd. PROJECT NUMBER...efficiency. A challenge with DC distribution is electrical protection . Z-source DC breakers alt! an pti n b&i g cvr.sidcrcd and this w rk ~xplores...zonal distribution, electric ship 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF a. REPORT b. ABSTRACT c. THIS PAGE ABSTRACT u u u uu 18. NUMBER

  9. A micro-optical system for endoscopy based on mechanical compensation paradigm using miniature piezo-actuation.

    Science.gov (United States)

    Cerveri, Pietro; Zazzarini, Cynthia Corinna; Patete, Paolo; Baroni, Guido

    2014-06-01

    The goal of the study was to investigate the feasibility of a novel miniaturized optical system for endoscopy. Fostering the mechanical compensation paradigm, the modeled optical system, composed by 14 lenses, separated in 4 different sets, had a total length of 15.55mm, an effective focal length ranging from 1.5 to 4.5mm with a zoom factor of about 2.8×, and an angular field of view up to 56°. Predicted maximum lens travel was less than 3.5mm. The consistency of the image plane height across the magnification range testified the zoom capability. The maximum predicted achromatic astigmatism, transverse spherical aberration, longitudinal spherical aberration and relative distortion were less than or equal to 25μm, 15μm, 35μm and 12%, respectively. Tests on tolerances showed that the manufacturing and opto-mechanics mounting are critical as little deviations from design dramatically decrease the optical performances. However, recent micro-fabrication technology can guarantee tolerances close to nominal design. A closed-loop actuation unit, devoted to move the zoom and the focus lens sets, was implemented adopting miniaturized squiggle piezo-motors and magnetic position encoders based on Hall effect. Performance results, using a prototypical test board, showed a positioning accuracy of less than 5μm along a lens travel path of 4.0mm, which was in agreement with the lens set motion features predicted by the analysis. In conclusion, this study demonstrated the feasibility of the optical design and the viability of the actuation approach while tolerances must be carefully taken into account. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

  10. Dielectric Actuation of Polymers

    Science.gov (United States)

    Niu, Xiaofan

    Dielectric polymers are widely used in a plurality of applications, such as electrical insulation, dielectric capacitors, and electromechanical actuators. Dielectric polymers with large strain deformations under an electric field are named dielectric elastomers (DE), because of their relative low modulus, high elongation at break, and outstanding resilience. Dielectric elastomer actuators (DEA) are superior to traditional transducers as a muscle-like technology: large strains, high energy densities, high coupling efficiency, quiet operation, and light weight. One focus of this dissertation is on the design of DE materials with high performance and easy processing. UV radiation curing of reactive species is studied as a generic synthesis methodology to provide a platform for material scientists to customize their own DE materials. Oligomers/monomers, crosslinkers, and other additives are mixed and cured at appropriate ratios to control the stress-strain response, suppress electromechanical instability of the resulting polymers, and provide stable actuation strains larger than 100% and energy densities higher than 1 J/g. The processing is largely simplified in the new material system by removal of the prestretching step. Multilayer stack actuators with 11% linear strain are demonstrated in a procedure fully compatible with industrial production. A multifunctional DE derivative material, bistable electroactive polymer (BSEP), is invented enabling repeatable rigid-to-rigid deformation without bulky external structures. Bistable actuation allows the polymer actuator to have two distinct states that can support external load without device failure. Plasticizers are used to lower the glass transition temperature to 45 °C. Interpenetrating polymer network structure is established inside the BSEP to suppress electromechanical instability, providing a breakdown field of 194 MV/m and a stable bistable strain as large as 228% with a 97% strain fixity. The application of BSEP

  11. Insights from a reliability review of digital plant protection system

    International Nuclear Information System (INIS)

    Kim, I.S.; Hwang, S.W.; Kim, B.S.; Jeong, C.H.; Oh, S.H.

    2001-01-01

    The full text follows: As part of the design efforts for Ulchin nuclear power plant units 5 and 6 of Korea, a reliability analysis of digital plant protection system (DPPS) was performed by ABB-CE. An independent review of the DPPS reliability analysis was undertaken by Hanyang University to assist Korea Institute of Nuclear Safety (KINS), the nuclear regulatory body of Korea, in evaluating the design acceptability of the digital system. The DPPS is designed to encompass both reactor trip function and ESFAS (engineered safety feature actuation system) initiation function. The major methods used by the ABB-CE to assess the Ulchin 5-6 DPPS reliability are failure mode and effect analysis (FMEA) and fault tree analysis. Hence, our independent review was conducted focusing on: -) the establishment of review criteria based on various sources, such as the standard review plan of KINS, 10CFR50 Appendix A, IEEE standards 279, 577, and 603; -) the suitability of the FMEA and fault tree analysis for the Ulchin 5-6 DPPS, including the specific methods used (e.g., for human reliability analysis and common-cause failure analysis), the assumptions made (e.g., with respect to test frequency and watchdog timer coverage), and the data employed (e.g., CCF parameter, human error probability, and processor failure rate); and -) the design acceptability of the DPPS especially as compared to the analog plant protection system from a reliability and safety perspective. The paper shall also discuss key issues requiring further in-depth investigation, such as reliability of programmable logic controllers (PLCs), coverage factor of watchdog timers, and susceptibility of redundant digital units to common cause failure. Sensitivity analyses were carried out to investigate the impact of several parameters of special interest, like the coverage factor of watchdog timer and human error probability (e.g. an operator error to manually trip the reactor, or to mis-calibrate the trip parameters) on

  12. Magnetic field generated by lightning protection system

    Science.gov (United States)

    Geri, A.; Veca, G. M.

    1988-04-01

    A lightning protection system for today's civil buildings must be electromagnetically compatible with the electronic equipment present in the building. This paper highlights a mathematic model which analyzes the electromagnetic effects in the environment in which the lightning protection system is. This model is developed by means of finite elements of an electrical circuit where each element is represented by a double pole circuit according to the trapezoidal algorithm developed using the finite difference method. It is thus possible to analyze the electromagnetic phenomena associated with the transient effects created by the lightning stroke even for a high-intensity current. Referring to an elementary system comprised of an air terminal, a down conductor, and a ground terminal, numerical results are here laid out.

  13. Expert systems for protective monitoring of facilities

    International Nuclear Information System (INIS)

    Carr, K.R.

    1987-01-01

    In complex plants, the possibility of serious operator error always exists to some extent, but, this can be especially true during an experiment or some other unusual exercise. Possible contributing factors to operational error include personnel fatigue, misunderstanding in communication, mistakes in executing orders, uncertainty about the delegated authority, pressure to meet a demanding schedule, and a lack of understanding of the possible consequences of deliberate violations of the facility's established operating procedures. Authoritative reports indicate that most of these factors were involved in the disastrous Russian Chernobyl-4 nuclear reactor accident in April 1986, which, ironically, occurred when a safety experiment was being conducted. Given the computer hardware and software now available for implementing expert systems together with integrated signal monitoring and communications, plant protection could be enhanced by an expert system with extended features to monitor the plant. The system could require information from the operators on a rigidly enforced schedule and automatically log in and report on a scheduled time basis to authorities at a central remote site during periods of safe operation. Additionally, the system could warn an operator or automatically shut down the plant in case of dangerous conditions, while simultaneously notifying independent, responsible, off-site personnel of the action taken. This approach would provide protection beyond that provided by typical facility scram circuits. This paper presents such an approach to implementing an expert system for plant protection, together with specific hardware and software configurations. The Chernobyl accident is used as the basis of discussion

  14. Thermally actuated linkage arrangement

    International Nuclear Information System (INIS)

    Anderson, P.M.

    1981-01-01

    A reusable thermally actuated linkage arrangement includes a first link member having a longitudinal bore therein adapted to receive at least a portion of a second link member therein, the first and second members being sized to effect an interference fit preventing relative movement there-between at a temperature below a predetermined temperature. The link members have different coefficients of thermal expansion so that when the linkage is selectively heated by heating element to a temperature above the predetermined temperature, relative longitudinal and/or rotational movement between the first and second link members is enabled. Two embodiments of a thermally activated linkage are disclosed which find particular application in actuators for a grapple head positioning arm in a nuclear reactor fuel handling mechanism to facilitate back-up safety retraction of the grapple head independently from the primary fuel handling mechanism drive system. (author)

  15. Fire protection countermeasures for containment ventilation systems

    International Nuclear Information System (INIS)

    Alvares, N.J.; Beason, D.G.; Bergman, W.; Ford, H.W.; Lipska, A.E.

    1980-01-01

    The goal of this project is to find countermeasures to protect HEPA filters in exit ventilation ducts from the heat and smoke generated by fire. Several methods for partially mitigating the smoke exposure to the HEPA filters were identified through testing and analysis. These independently involve controlling the fuel, controlling the fire, and intercepting the smoke aerosol prior to its sorption on the HEPA filter. Exit duct treatment of aerosols is not unusual in industrial applications and involves the use of scrubbers, prefilters, and inertial impaction, depending on the size, distribution, and concentration of the subject aerosol. However, when these unmodified techniques were applied to smoke aerosols from fires on materials, common to experimental laboratories of LLNL, it was found they offered minimal protection to the HEPA filters. Ultimately, a continuous, movable, high-efficiency prefilter using modified commercial equipment was designed. This technique is capable of protecting HEPA filters over the total duration of the test fires. The reason for success involved the modificaton of the prefiltration media. Commercially available filter media has a particle sorption efficiency that is inversely proportional to media strength. To achieve properties of both efficiency and strength, we laminated rolling filter media with the desired properties. It is not true that the use of rolling prefilters solely to protect HEPA filters from fire-generated smoke aerosols is cost effective in every type of containment system, especially if standard fire-protection systems are available in the space. But in areas of high fire risk, where the potential fuel load is large and ignition sources are plentiful, the complication of a rolling prefilter in exit ventilation ducts to protect HEPA filters from smoke aerosols is definitely justified

  16. Design and Performance Evaluation of Sensors and Actuators for Advanced Optical Systems

    Science.gov (United States)

    Clark, Natalie

    2011-01-01

    Current state-of-the-art commercial sensors and actuators do not meet many of NASA s next generation spacecraft and instrument needs. Nor do they satisfy the DoD needs for satellite missions, especially micro/nano satellite missions. In an effort to develop advanced optical devices and instruments that meet mission requirements, NASA Langley recently completed construction of a new cleanroom housing equipment capable of fabricating high performance active optic and adaptive optic technologies including deformable mirrors, reconfigurable lenses (both refractive and diffractive), spectrometers, spectro-polarimeters, tunable filters and many other active optic devices. In addition to performance, these advanced optic technologies offer advantages in speed, size, weight, power consumption, and radiation tolerance. The active optic devices described in this paper rely on birefringent liquid crystal materials to alter either the phase or the polarization of the incoming light. Design considerations and performance evaluation results for various NASA applications are presented. Applications presented will include large space telescopes, optical communications, spacecraft windows, coronagraphs, and star trackers. Keywords: Photonics, Adaptive Optics, Tunable Filters, MEMs., MOEMs, Coronagraph, Star Tracker

  17. A computational simulated control system for a high-force pneumatic muscle actuator: system definition and application as an augmented orthosis.

    Science.gov (United States)

    Gerschutz, Maria J; Phillips, Chandler A; Reynolds, David B; Repperger, Daniel W

    2009-04-01

    High-force pneumatic muscle actuators (PMAs) are used for force assistance with minimal displacement applications. However, poor control due to dynamic nonlinearities has limited PMA applications. A simulated control system is developed consisting of: (1) a controller relating an input position angle to an output proportional pressure regulator voltage, (2) a phenomenological model of the PMA with an internal dynamic force loop (system time constant information), (3) a physical model of a human sit-to-stand task and (4) an external position angle feed-back loop. The results indicate that PMA assistance regarding the human sit-to-stand task is feasible within a specified PMA operational pressure range.

  18. Piezoelectric actuator based phase locking system to improve the dynamics of the control scheme for a heavy ion superconducting linac

    Energy Technology Data Exchange (ETDEWEB)

    Sahu, B.K., E-mail: bhuban@iuac.res.in [Inter University Accelerator Centre (IUAC), Aruna Asaf Ali Marg, New Delhi – 110 067 (India); Ahuja, R.; Kumar, Rajesh; Suman, S.K.; Mathuria, D.S.; Rai, A.; Patra, P.; Pandey, A.; Karmakar, J.; Chowdhury, G.K.; Dutt, R.N. [Inter University Accelerator Centre (IUAC), Aruna Asaf Ali Marg, New Delhi – 110 067 (India); Joshi, G. [Electronics Division, Bhabha Atomic Research Centre, Mumbai – 400 085 (India); Ghosh, S.; Kanjilal, D.; Roy, A. [Inter University Accelerator Centre (IUAC), Aruna Asaf Ali Marg, New Delhi – 110 067 (India)

    2015-03-21

    The superconducting heavy ion linear accelerator at Inter-University Accelerator Centre Delhi has been in operation since 2007. Initially, the superconducting niobium Quarter Wave Resonators (QWRs) in the linac were phase locked using a combination of electronic and mechanical controls which operated in fast (~10 μsec) and slow (~sec) time scales respectively. In this scheme, fast control was achieved through dynamic phase control whereas slow control of the frequency was done through the niobium tuner bellows installed at the drift tube end of the resonator and flexed using helium gas to change the resonance frequency. In order to improve the dynamics of this control system, an alternate scheme using piezoelectric actuator, instead of helium gas, to flex the same niobium bellows, has been implemented in the QWRs of the second and third accelerating modules of the linac. The piezoelectric actuator is used in closed loop along with the fast dynamic phase control scheme. The feedback loop of the piezoelectric control includes a dual control scheme - an integral control loop to arrest the slow drift, and the positive position feedback (PPF) based control loop to damp the microphonics. This control scheme has been found to arrest slow drifts in the resonator frequency more tightly along with damping of low frequency microphonics (~few tens of Hz) picked up by the resonator from its surrounding environment. This has substantially eased the load from the fast electronic control, resulting in the reduction of the radio frequency (RF) power requirement during operation. In addition, it has improved the stability of phase and amplitude of the QWRs. The details of the new scheme along with results obtained during the online run of the linac for beam acceleration are presented.

  19. Fire protection countermeasures for containment ventilation systems

    International Nuclear Information System (INIS)

    Alvares, N.; Beason, D.; Bergman, V.; Creighton, J.; Ford, H.; Lipska, A.

    1980-01-01

    The goal of this project is to find countermeasures to protect High Efficiency Particulate Air (HEPA) filters, in exit ventilation ducts, from the heat and smoke generated by fire. Initially, methods were developed to cool fire-heated air by fine water spray upstream of the filters. It was recognized that smoke aerosol exposure to HEPA filters could also cause disruption of the containment system. Through testing and analysis, several methods to partially mitigate the smoke exposure to the HEPA filters were identified. A continuous, movable, high-efficiency prefilter using modified commercial equipment was designed. The technique is capable of protecting HEPA filters over the total time duration of the test fires. The reason for success involved the modification of the prefiltration media. Commercially available filter media has particle sorption efficiency that is inversely proportional to media strength. To achieve properties of both efficiency and strength, rolling filter media were laminated with the desired properties. The approach was Edisonian, but truncation in short order to a combination of prefilters was effective. The application of this technique was qualified, since it is of use only to protect HEPA filters from fire-generated smoke aerosols. It is not believed that this technique is cost effective in the total spectrum of containment systems, especially if standard fire protection systems are available in the space. But in areas of high-fire risk, where the potential fuel load is large and ignition sources are plentiful, the complication of a rolling prefilter in exit ventilation ducts to protect HEPA filters from smoke aerosols is definitely justified

  20. Protective underpressure system for nuclear power plants

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    A vacuum protection system for a nuclear reactor is described containng the possible accident in the immediate area where it happened. The system uses underpressure in the air-tight primary circuit jacket. Immediately after the accident, part of air is forced out from the area where coolant is being lost to another area which is then separated from the accident area. The desired underpressure is attained by steam condensation. A system diagram is shown and the time-dependent pressure changes in the contained areas are presented. (J.B.)

  1. Incipient fault detection and power system protection for spaceborne systems

    Science.gov (United States)

    Russell, B. Don; Hackler, Irene M.

    1987-01-01

    A program was initiated to study the feasibility of using advanced terrestrial power system protection techniques for spacecraft power systems. It was designed to enhance and automate spacecraft power distribution systems in the areas of safety, reliability and maintenance. The proposed power management/distribution system is described as well as security assessment and control, incipient and low current fault detection, and the proposed spaceborne protection system. It is noted that the intelligent remote power controller permits the implementation of digital relaying algorithms with both adaptive and programmable characteristics.

  2. Sub-assembly accident protection instrumentation systems

    International Nuclear Information System (INIS)

    Vaughan, G.J.; Lunt, A.R.W.; Evans, N.J.; Lawrence, L.A.J.

    1982-01-01

    The possibility of an incident in a sub-assembly progressing to the stage at which the whole core may be at hazard has to be guarded against. It is proposed that for CDFR specific instrumentation will be provided to protect against this incident. Three such systems are described, these are: Acoustic Boiling Noise Detection, Burst Pin Detection and Individual Sub-Assembly Thermocouple (ISAT) monitoring. In the ISAT case, multiplexers and microprocessors are employed, using novel techniques to ensure failure-to-safety. The role of these systems and the implementation of them in the reactor design are also considered. It is concluded that sufficient protection can be provided for both core and breeder sub-assemblies

  3. Study of piezo-actuators for the improvement of the frequency tuning and setup of a quench locating system for the accelerating structures of the S-DALINAC

    International Nuclear Information System (INIS)

    Sievers, Sven Thorsten

    2013-01-01

    The intention of this doctoral thesis was to find a replacement for the magnetostrictive fine tuners of the superconducting accelerating cavities of the S-DALINAC and to enlarge the range of diagnostics for these cavities. For these purposes a vertical bath cryostat has been assembled and put into operation. Within the framework of this thesis that cryostat was used (i) to test stroke and reliability of modern piezo actuators in liquid helium at 4 and 2 K and (ii) to set up a newly developed system for the localization of quenches in superconducting cavities based on second sound in superfluid helium. The negative impact of magnetic fields on the quality factor of superconducting cavities make the operation of magnetostrictive tuners nearby the cavities disadvantageous. In order to avoid a decrease of the quality factor of the cavities the magnetostrictive tuners should be replaced by non-magnetic ones. For that purpose modern piezo actuators were tested within this doctoral thesis relating to their stroke at cryogenic temperatures, their compatibility with the RF-control system of the S-DALINAC and their operational reliability in superfluid helium. The results indicate the possibility of operation of these actuators. Because piezo actuators of the same stroke only have the seventh part of length of a magnetostrictive tuner, it is possible to operate several piezo actuators at every cavity. This increases not only the range of the tuning system but also its reliability. Already tiny defects at the inner surface of superconducting cavities can cause quenching before the designed field intensity is reached. A quench results in waves of second sound in superfluid helium. The second sound can be measured by special microphones, so called Oscillating Superleak Transducers (OST), and the location of quenching can be calculated via triangulation. Such a system has been built up and tested successfully in the context of this doctoral thesis. The visual examination of the

  4. Technical improvement for the output drive unit of the reactor protection system in QNPP

    International Nuclear Information System (INIS)

    Jiang Zuyue

    1995-11-01

    For improving the reliability of the output drive unit of the reactor protection system in Qinshan NPP, the former design of this part was improved and researched on the problem appeared during the commissioning and operation under the conditions of narrow process space of cabinets and unchanged overall arrangement: (1) The output relay modules was redesigned to unify the relay specification to improve the versatility, and also to improve the pin's contact by means of welding them directly on the printed circuit boards and to make the modules detachable by connectors instead of previously non-detachable. Th modules were connected in series by both power supply line and ground line which were finally connected at same point respectively, so that other protection signals can still be output correctly when a single module is removed. (2) The relay drive circuit was also redesigned for working in on-off state instead of in amplification to minimize the power consumption. On the other hand, the CMOS buffers were taken to couple the CMOS circuits to the TTL circuits. The actuating time for the new shutdown relay was decreased from the former 35 ms to 5 ms, the actuating time for the engineered safety feature drive signal relay was decreased from 10 ms to 6 ms after the above-mentioned improvements, the reliability of the RPS is remarkably improved and a great economic benefit is obtained. (4 refs., 3 figs., 2 tabs.)

  5. Development of In-Core Protection System

    International Nuclear Information System (INIS)

    Cho, J. H; Kim, C. H.; Kim, J. H.; Jeong, S. H.; Sohn, S. D.; BaeK, S. M.; YOON, J. H.

    2016-01-01

    In-core Protection System (ICOPS) is an on-line digital computer system which continuously calculates Departure from Nucleate Boiling Ratio (DNBR) and Local Power Density (LPD) based on plant parameters to make trip decisions based on the computations. The function of the system is the same as that of Core Protection Calculator System (CPCS) and Reactor Core Protection System (RCOPS) which are applied to Optimized Power Reactor 1000 (OPR1000) and Advanced Power Reactor 1400 (APR1400). The ICOPS has been developed to overcome the algorithm related obstacles in overseas project. To achieve this goal, several algorithms were newly developed and hardware and software design was updated. The functional design requirements document was developed by KEPCO-NF and the component design was conducted by Doosan. System design and software implementation were performed by KEPCO-E and C, and software Verification and Validation (V and V) was performed by KEPCO-E and C and Sure Softtech. The ICOPS has been developed to overcome the algorithm related obstacles in overseas project. The function of I/O simulator was improved even though the hardware platform is the same as that of RCOPS for Shin-Hanul 1 and 2. SCADE was applied to the implementation of ICOPS software, and the V and V system for ICOPS which satisfies international standards was developed. Although several further detailed design works remain, the function of ICOPS has been confirmed. The ICOPS will be applied to APR+ project, and the further works will be performed in following project

  6. Development of In-Core Protection System

    Energy Technology Data Exchange (ETDEWEB)

    Cho, J. H; Kim, C. H.; Kim, J. H.; Jeong, S. H.; Sohn, S. D.; BaeK, S. M.; YOON, J. H. [KEPCO Engineering and Construction Co., Deajeon (Korea, Republic of)

    2016-10-15

    In-core Protection System (ICOPS) is an on-line digital computer system which continuously calculates Departure from Nucleate Boiling Ratio (DNBR) and Local Power Density (LPD) based on plant parameters to make trip decisions based on the computations. The function of the system is the same as that of Core Protection Calculator System (CPCS) and Reactor Core Protection System (RCOPS) which are applied to Optimized Power Reactor 1000 (OPR1000) and Advanced Power Reactor 1400 (APR1400). The ICOPS has been developed to overcome the algorithm related obstacles in overseas project. To achieve this goal, several algorithms were newly developed and hardware and software design was updated. The functional design requirements document was developed by KEPCO-NF and the component design was conducted by Doosan. System design and software implementation were performed by KEPCO-E and C, and software Verification and Validation (V and V) was performed by KEPCO-E and C and Sure Softtech. The ICOPS has been developed to overcome the algorithm related obstacles in overseas project. The function of I/O simulator was improved even though the hardware platform is the same as that of RCOPS for Shin-Hanul 1 and 2. SCADE was applied to the implementation of ICOPS software, and the V and V system for ICOPS which satisfies international standards was developed. Although several further detailed design works remain, the function of ICOPS has been confirmed. The ICOPS will be applied to APR+ project, and the further works will be performed in following project.

  7. Lightning protection system for a wind turbine

    Science.gov (United States)

    Costin, Daniel P [Chelsea, VT; Petter, Jeffrey K [Williston, VT

    2008-05-27

    In a wind turbine (104, 500, 704) having a plurality of blades (132, 404, 516, 744) and a blade rotor hub (120, 712), a lightning protection system (100, 504, 700) for conducting lightning strikes to any one of the blades and the region surrounding the blade hub along a path around the blade hub and critical components of the wind turbine, such as the generator (112, 716), gearbox (708) and main turbine bearings (176, 724).

  8. Halon 1301 protection system for nuclear containments

    International Nuclear Information System (INIS)

    McHale, E.T.

    1981-01-01

    Halon 1301 can provide protection against any combustion hazard that hydrogen gas might present in an LWR containment following a loss-of-coolant accident. A development program was conducted, comprising analytical study, laboratory experiments and large-scale testing, to define the requirements for a Halon 1301 system and to examine certain operational problems that were hypothesized. Some results of the study are presented in this paper

  9. Protection of LV system against lightning

    OpenAIRE

    Yordanova Nedyalkova, Greta

    2010-01-01

    Lightning is a natural hazard and one of the greatest local mysteries. Scientists have not fully understood the mechanism of lightning. It is one of the most beautiful displays in nature and one of the nature's most dangerous phenomenon known to man. Overvoltage due to lightning is a very important problem of LV systems. Some lightning flashes damage buildings and a few kill or injure people and animals, either directly or indirectly, by causing fire and explosions. The need for protect...

  10. Beam loss monitor system for machine protection

    CERN Document Server

    Dehning, B

    2005-01-01

    Most beam loss monitoring systems are based on the detection of secondary shower particles which depose their energy in the accelerator equipment and finally also in the monitoring detector. To allow an efficient protection of the equipment, the likely loss locations have to be identified by tracking simulations or by using low intensity beams. If superconducting magnets are used for the beam guiding system, not only a damage protection is required but also quench preventions. The quench levels for high field magnets are several orders of magnitude below the damage levels. To keep the operational efficiency high under such circumstances, the calibration factor between the energy deposition in the coils and the energy deposition in the detectors has to be accurately known. To allow a reliable damage protection and quench prevention, the mean time between failures should be high. If in such failsafe system the number of monitors is numerous, the false dump probability has to be kept low to keep a high operation...

  11. Enhanced personal protection system for the PS

    CERN Multimedia

    Caroline Duc

    2013-01-01

    During the first long shutdown (LS1) a new safety system will be installed in the primary beam areas of the PS complex in order to bring the standard of personnel radiation protection at the PS into line with that of the LHC.   Pierre Ninin, deputy group leader of GS-ASE and responsible for the installation of the new PS complex safety system, in front of a new access control system. The LHC access control systems are state-of-the-art, whereas those of the injection chain accelerators were running the risk of becoming obsolete. For the past two years a project to upgrade the access and safety systems of the first links in the LHC accelerator chain has been underway to bring them into compliance with nuclear safety standards. These systems provide the personnel with automatic protection by limiting access to hazardous areas and by ensuring that nobody is present in the areas when the accelerator is in operation. By the end of 2013, the project teams will ha...

  12. Characterization of a smartphone size haptic rendering system based on thin-film AlN actuators on glass substrates

    Science.gov (United States)

    Bernard, F.; Casset, F.; Danel, J. S.; Chappaz, C.; Basrour, S.

    2016-08-01

    This paper presents for the first time the characterization of a smartphone-size haptic rendering system based on the friction modulation effect. According to previous work and finite element modeling, the homogeneous flexural modes are needed to get the haptic feedback effect. The device studied consists of a thin film AlN transducers deposited on an 110  ×  65 mm2 glass substrate. The transducer’s localization on the glass plate allows a transparent central area of 90  ×  49 mm2. Electrical and mechanical parameters of the system are extracted from measurement. From this extraction, the electrical impedance matching reduced the applied voltage to 17.5 V AC and the power consumption to 1.53 W at the resonance frequency of the vibrating system to reach the haptic rendering specification. Transient characterizations of the actuation highlight a delay under the dynamic tactile detection. The characterization of the AlN transducers used as sensors, including the noise rejection, the delay or the output charge amplitude allows detections with high accuracy of any variation due to external influences. Those specifications are the first step to a low-power-consumption feedback-looped system.

  13. Characterization of a smartphone size haptic rendering system based on thin-film AlN actuators on glass substrates

    International Nuclear Information System (INIS)

    Bernard, F; Basrour, S; Casset, F; Danel, J S; Chappaz, C

    2016-01-01

    This paper presents for the first time the characterization of a smartphone-size haptic rendering system based on the friction modulation effect. According to previous work and finite element modeling, the homogeneous flexural modes are needed to get the haptic feedback effect. The device studied consists of a thin film AlN transducers deposited on an 110  ×  65 mm 2 glass substrate. The transducer’s localization on the glass plate allows a transparent central area of 90  ×  49 mm 2 . Electrical and mechanical parameters of the system are extracted from measurement. From this extraction, the electrical impedance matching reduced the applied voltage to 17.5 V AC and the power consumption to 1.53 W at the resonance frequency of the vibrating system to reach the haptic rendering specification. Transient characterizations of the actuation highlight a delay under the dynamic tactile detection. The characterization of the AlN transducers used as sensors, including the noise rejection, the delay or the output charge amplitude allows detections with high accuracy of any variation due to external influences. Those specifications are the first step to a low-power-consumption feedback-looped system. (paper)

  14. The combined effect of thermal and chemotherapy on HeLa cells using magnetically actuated smart textured fibrous system.

    Science.gov (United States)

    Tiwari, Pranav; Agarwal, Sakshi; Srivastava, Sachchidanand; Jain, Shilpee

    2018-01-01

    Thermal therapy combined with chemotherapy is one of the advanced and efficient methods to eradicate cancer. In this work, we fabricated magnetically actuated smart textured (MAST) fibrous systems and studied their candidacy for cancer treatment. The polycaprolactone-Fe 3 O 4 based MAST fibers were fabricated using electrospinning technique. These MAST fibrous systems contained carbogenic quantum dots as a tracking agent and doxorubicin hydrochloride anticancer drug. Additionally, as fabricated MAST fibrous systems were able to deliver anticancer drug and heat energy simultaneously to kill HeLa cells in a 10 min period in vitro. After treatment, the metabolic activity and morphology of HeLa cells were analyzed. In addition, the mechanism of cell death was studied using flow cytometry. Interestingly, the navigation of these systems in the fluid can be controlled with the application of gradient magnetic field. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 40-51, 2018. © 2016 Wiley Periodicals, Inc.

  15. Advanced Electroactive Single Crystal and Polymer Actuator Concepts for Passive Optics, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — TRS Technologies proposes large stroke and high precision piezoelectric single crystal and electroactive polymer actuator concepts?HYBrid Actuation System (HYBAS)...

  16. Coherence protection in coupled quantum systems

    Science.gov (United States)

    Cammack, H. M.; Kirton, P.; Stace, T. M.; Eastham, P. R.; Keeling, J.; Lovett, B. W.

    2018-02-01

    The interaction of a quantum system with its environment causes decoherence, setting a fundamental limit on its suitability for quantum information processing. However, we show that if the system consists of coupled parts with different internal energy scales then the interaction of one part with a thermal bath need not lead to loss of coherence from the other. Remarkably, we find that the protected part can remain coherent for longer when the coupling to the bath becomes stronger or the temperature is raised. Our theory will enable the design of decoherence-resistant hybrid quantum computers.

  17. Integrated nuclear and radiation protection systems

    International Nuclear Information System (INIS)

    Oprea, I.; Oprea, M.; Stoica, V.; Cerga, V.; Pirvu, V.; Badea, E.

    1993-01-01

    A multifunctional radiation monitoring equipment, flexible and capable to meet virtually environmental radiation monitoring, activity measurement and computational requirements, for nuclear laboratories has been designed. It can be used as a radiation protection system, for radionuclide measurement in isotope laboratories, nuclear technology, health physics and nuclear medicine, nuclear power stations and nuclear industry. The equipment is able to measure, transmit and record gamma dose rate and isotope activities. Other parameters and functions are optionally available, such as: self-contained alarm level, system self-test, dose integrator, syringe volume calculation for a given dose corrected for decay, calibration factor, 99 Mo assays performing and background subtraction

  18. River Protection Project information systems assessment

    Energy Technology Data Exchange (ETDEWEB)

    JOHNSON, A.L.

    1999-07-28

    The Information Systems Assessment Report documents the results from assessing the Project Hanford Management Contract (PHMC) Hanford Data Integrator 2000 (HANDI 2000) system, Business Management System (BMS) and Work Management System phases (WMS), with respect to the System Engineering Capability Assessment Model (CAM). The assessment was performed in accordance with the expectations stated in the fiscal year (FY) 1999 Performance Agreement 7.1.1, item (2) which reads, ''Provide an assessment report on the selected Integrated Information System by July 31, 1999.'' This report assesses the BMS and WMS as implemented and planned for the River Protection Project (RPP). The systems implementation is being performed under the PHMC HANDI 2000 information system project. The project began in FY 1998 with the BMS, proceeded in FY 1999 with the Master Equipment List portion of the WMS, and will continue the WMS implementation as funding provides. This report constitutes an interim quality assessment providing information necessary for planning RPP's information systems activities. To avoid confusion, HANDI 2000 will be used when referring to the entire system, encompassing both the BMS and WMS. A graphical depiction of the system is shown in Figure 2-1 of this report.

  19. River Protection Project information systems assessment

    International Nuclear Information System (INIS)

    JOHNSON, A.L.

    1999-01-01

    The Information Systems Assessment Report documents the results from assessing the Project Hanford Management Contract (PHMC) Hanford Data Integrator 2000 (HANDI 2000) system, Business Management System (BMS) and Work Management System phases (WMS), with respect to the System Engineering Capability Assessment Model (CAM). The assessment was performed in accordance with the expectations stated in the fiscal year (FY) 1999 Performance Agreement 7.1.1, item (2) which reads, ''Provide an assessment report on the selected Integrated Information System by July 31, 1999.'' This report assesses the BMS and WMS as implemented and planned for the River Protection Project (RPP). The systems implementation is being performed under the PHMC HANDI 2000 information system project. The project began in FY 1998 with the BMS, proceeded in FY 1999 with the Master Equipment List portion of the WMS, and will continue the WMS implementation as funding provides. This report constitutes an interim quality assessment providing information necessary for planning RPP's information systems activities. To avoid confusion, HANDI 2000 will be used when referring to the entire system, encompassing both the BMS and WMS. A graphical depiction of the system is shown in Figure 2-1 of this report

  20. Fault Detection for Diesel Engine Actuator

    DEFF Research Database (Denmark)

    Blanke, M.; Bøgh, S.A.; Jørgensen, R.B.

    1994-01-01

    Feedback control systems are vulnerable to faults in control loop sensors and actuators, because feedback actions may cause abrupt responses and process damage when faults occur.......Feedback control systems are vulnerable to faults in control loop sensors and actuators, because feedback actions may cause abrupt responses and process damage when faults occur....

  1. Smart Tendon Actuated Flexible Actuator

    Directory of Open Access Journals (Sweden)

    Md. Masum Billah

    2015-01-01

    Full Text Available We investigate the kinematic feasibility of a tendon-based flexible parallel platform actuator. Much of the research on tendon-driven Stewart platforms is devoted either to the completely restrained positioning mechanism (CRPM or to one particular type of the incompletely restrained positioning mechanism (IRPM where the external force is provided by the gravitational pull on the platform such as in cable-suspended Stewart platforms. An IRPM-based platform is proposed which uses the external force provided by a compliant member. The compliant central column allows the configuration to achieve n DOFs with n tendons. In particular, this investigation focuses on the angular deflection of the upper platform with respect to the lower platform. The application here is aimed at developing a linkable module that can be connected to one another so as to form a “snake robot” of sorts. Since locomotion takes precedence over positioning in this application, a 3-DOF Stewart platform is adopted. For an arbitrary angular displace of the end-effector, the corresponding length of each tendon can be determined through inverse kinematics. Mathematical singularities are investigated using the traditional analytical method of defining the Jacobian.

  2. PG BN 1600 sodium fire protection system

    International Nuclear Information System (INIS)

    Bar, J.; Urbancik, L.

    1978-12-01

    A design was developed of a fire protection system for steam generator of a 1600 MW sodium cooled fast reactor (BN-1600). Chemical reactions are described of liquid sodium with atmospheric components and solid materials coming into contact with sodium in its release from the steam generator, and in safeguarding protection against sodium fires. The requirements for the purity of nitrogen as an atmosphere inert to liquid sodium are given. Characteristics and basic parameters are shown of level and spray fires, elementary terms are explained concerning the properties of aerosols formed during fires, the methods and means of release signalling and fire alarm are described as are fire precautions using fire-fighting equipment, modifying the support tank and the cell bottom and building sewage pits. The design of the system comprises an alarm system for liquid sodium using point and line electric contact sensors and flame photometer based aerosol sensors as well as a fire-fighting system based on the system of channelling liquid sodium into emergency discharge tanks filled with an inert gas, a set of fire extinguishers and other fire fighting material, and measures for the elimination of sodium fire consequences. (J.B.)

  3. Application Software for the Cabinet Operator Module of the Reactor Protection System

    International Nuclear Information System (INIS)

    Lee, Hyun-Chul; Jung, Hae-Won; Lee, Sung-Jin; Koo, Young-Ho; Kim, Seong-Tae; Kwak, Tae-Kil; Jin, Kyo-Hong

    2006-01-01

    A reactor protection system (RPS) plays the roles of generating the reactor trip signal and the engineered safety features (ESF) actuation signal when the monitored plant processes reach predefined limits. A Korean project group, so-called KNICS (Korean Nuclear I and C System), is developing a new digitalized RPS and the Cabinet Operator Module (COM) of the RPS which is used for the RPS integrity testing and monitoring by equipment operators. A flat panel display (FPD) with a touch screen capability is provided as a main user interface for the RPS. This paper shows the application software developed for the COM FPD. Equipment operators can monitor the status of the RPS and carry out various tests to verify system functions by means of the application software. A qualified hardware and software development environment are used to develop the application software

  4. National Ignition Facility environmental protection systems

    International Nuclear Information System (INIS)

    Mintz, J.M.; Reitz, T.C.; Tobin, M.T.

    1994-06-01

    The conceptual design of Environmental Protection Systems (EPS) for the National Ignition Facility (NIF) is described. These systems encompass tritium and activated debris handling, chamber, debris shield and general decontamination, neutron and gamma monitoring, and radioactive, hazardous and mixed waste handling. Key performance specifications met by EPS designs include limiting the tritium inventory to 300 Ci and total tritium release from NIF facilities to less than 10 Ci/yr. Total radiation doses attributable to NIF shall remain below 10 mrem/yr for any member of the general public and 500 mrem/yr for NIF staff. ALARA-based design features and operational procedures will, in most cases, result in much lower measured exposures. Waste minimization, improved cycle time and reduced exposures all result from the proposed CO2 robotic arm cleaning and decontamination system, while effective tritium control is achieved through a modern system design based on double containment and the proven detritiation technology

  5. Radiological protection national system. Basic security rules

    International Nuclear Information System (INIS)

    1981-01-01

    This work has been prepared as the first one of a set of standards and regulations that will be enforced to provide the protection of men and the environment against the undesirable effects of ionizing radiations. It establishes, in the first place, the system of dose limits for the country and the principles of its utilization. It takes into account the CIPR's recommendations in this area and the mentioned frame of reference, it establishes further the necessary restrictions for the application of the limits to the professionally exposed workers, as well as to the isolated members of the public and the population in general. In addition it establishes the general conditions to be met for the implementation of radiological protection, among them, the classification of working areas and working conditions as well as the compulsory periodical medical surveillance. (H.D.N.)

  6. Radiological protection system in the era of nuclear renaissance expectation for development of radiological protection system

    International Nuclear Information System (INIS)

    Toyomatsu, Hideki

    2008-01-01

    The current radiological protection system, which was established mainly by the ICRP and UNSCEAR, has contributed to the prevention of potential radiological health hazards, and has been a fundamental concept during the development of nuclear energy. Through a detailed discussion regarding the new ICRP recommendations, the world nuclear industry has reached a consensus that the current radiological protection system keeps its integrity in principle although it involves some remaining issues, such as the disposal of radioactive waste. In order to maximize the advantages of nuclear energy while keeping the integrity of radiological protection system, it is essential to address the characteristics of radiation, which is specific to nuclear energy, so that nuclear energy can coexist with other energy sources. The three basic principles of radiological protection (i.e., justification, optimization and dose limits), which were completed in the 1990 recommendations of ICRP, should be retained as the basic concepts for the future radiological protection system in order to maintain the continuity and consistency of the radiological protection system. The radiological protection system can be furthermore developed only by combining the above three principles with best practices extracted from utilities' field experience. The significant reduction of radiation exposures received by members of the public and radiation workers in the field has resulted from the efforts by the world utilities to achieve the optimization. In order to correctly apply the theory to the work practices, it is essential to see how the theory is practically used in the field. Such a process should be also emphasized in the revision work of the IAEA Basic Safety Standards (BSS), which is currently under progress. Integrating the theory in the work practices is the key to the true development of nuclear renaissance, which could lead to the establishment of the nuclear safety regime. (author)

  7. An intelligent sensor array distributed system for vibration analysis and acoustic noise characterization of a linear switched reluctance actuator.

    Science.gov (United States)

    Salvado, José; Espírito-Santo, António; Calado, Maria

    2012-01-01

    This paper proposes a distributed system for analysis and monitoring (DSAM) of vibrations and acoustic noise, which consists of an array of intelligent modules, sensor modules, communication bus and a host PC acting as data center. The main advantages of the DSAM are its modularity, scalability, and flexibility for use of different type of sensors/transducers, with analog or digital outputs, and for signals of different nature. Its final cost is also significantly lower than other available commercial solutions. The system is reconfigurable, can operate either with synchronous or asynchronous modes, with programmable sampling frequencies, 8-bit or 12-bit resolution and a memory buffer of 15 kbyte. It allows real-time data-acquisition for signals of different nature, in applications that require a large number of sensors, thus it is suited for monitoring of vibrations in Linear Switched Reluctance Actuators (LSRAs). The acquired data allows the full characterization of the LSRA in terms of its response to vibrations of structural origins, and the vibrations and acoustic noise emitted under normal operation. The DSAM can also be used for electrical machine condition monitoring, machine fault diagnosis, structural characterization and monitoring, among other applications.

  8. An Intelligent Sensor Array Distributed System for Vibration Analysis and Acoustic Noise Characterization of a Linear Switched Reluctance Actuator

    Directory of Open Access Journals (Sweden)

    Maria Calado

    2012-06-01

    Full Text Available This paper proposes a distributed system for analysis and monitoring (DSAM of vibrations and acoustic noise, which consists of an array of intelligent modules, sensor modules, communication bus and a host PC acting as data center. The main advantages of the DSAM are its modularity, scalability, and flexibility for use of different type of sensors/transducers, with analog or digital outputs, and for signals of different nature. Its final cost is also significantly lower than other available commercial solutions. The system is reconfigurable, can operate either with synchronous or asynchronous modes, with programmable sampling frequencies, 8-bit or 12-bit resolution and a memory buffer of 15 kbyte. It allows real-time data-acquisition for signals of different nature, in applications that require a large number of sensors, thus it is suited for monitoring of vibrations in Linear Switched Reluctance Actuators (LSRAs. The acquired data allows the full characterization of the LSRA in terms of its response to vibrations of structural origins, and the vibrations and acoustic noise emitted under normal operation. The DSAM can also be used for electrical machine condition monitoring, machine fault diagnosis, structural characterization and monitoring, among other applications.

  9. Development of monitoring, control and protection systems of nuclear power reactors in the USSR: Status and trends

    International Nuclear Information System (INIS)

    Kondrat'ev, V.V.; Mikhailov, M.N.; Prozorov, V.K.; Chudin, A.G.

    1992-01-01

    In 1989-90 the Supervision Body approved the new safety regulations for nuclear power plants. The operating plants do not always completely satisfy them and a great amount of work to develop operating power units up to the conditions required is necessary. This paper describes briefly the main changes made in monitoring, control and protection systems of nuclear power reactors to increase the reactor safety. The following fields are presented in the paper: General status of the NPP control and safety systems and instrumentation in USSR; sensors; electronic equipment; actuators improvement; qualification tests. (author). 3 figs

  10. TREAT Reactor Control and Protection System

    International Nuclear Information System (INIS)

    Lipinski, W.C.; Brookshier, W.K.; Burrows, D.R.; Lenkszus, F.R.; McDowell, W.P.

    1985-01-01

    The main control algorithm of the Transient Reactor Test Facility (TREAT) Automatic Reactor Control System (ARCS) resides in Read Only Memory (ROM) and only experiment specific parameters are input via keyboard entry. Prior to executing an experiment, the software and hardware of the control computer is tested by a closed loop real-time simulation. Two computers with parallel processing are used for the reactor simulation and another computer is used for simulation of the control rod system. A monitor computer, used as a redundant diverse reactor protection channel, uses more conservative setpoints and reduces challenges to the Reactor Trip System (RTS). The RTS consists of triplicated hardwired channels with one out of three logic. The RTS is automatically tested by a digital Dedicated Microprocessor Tester (DMT) prior to the execution of an experiment. 6 refs., 5 figs., 1 tab

  11. Soft, Rotating Pneumatic Actuator.

    Science.gov (United States)

    Ainla, Alar; Verma, Mohit S; Yang, Dian; Whitesides, George M

    2017-09-01

    This article describes a soft pneumatic actuator that generates cyclical motion. The actuator consists of several (three, four, or five) chambers (arranged around the circumference of a circle surrounding a central rod) that can be actuated independently using negative pressure (or partial vacuum). Sequential actuation of the four-chamber device using reduced pressure moves the central rod cyclically in an approximately square path. We characterize the trajectory of the actuator and the force exerted by it, as we vary the material used for fabrication, the number of chambers, and the size of the actuator. We demonstrate two applications of this actuator: to deliver fluid while stirring (by replacing the central rod with a needle) and for locomotion that mimics a reptilian gait (by combining four actuators together).

  12. Fault-tolerant reactor protection system

    International Nuclear Information System (INIS)

    Gaubatz, D.C.

    1997-01-01

    A reactor protection system is disclosed having four divisions, with quad redundant sensors for each scram parameter providing input to four independent microprocessor-based electronic chassis. Each electronic chassis acquires the scram parameter data from its own sensor, digitizes the information, and then transmits the sensor reading to the other three electronic chassis via optical fibers. To increase system availability and reduce false scrams, the reactor protection system employs two levels of voting on a need for reactor scram. The electronic chassis perform software divisional data processing, vote 2/3 with spare based upon information from all four sensors, and send the divisional scram signals to the hardware logic panel, which performs a 2/4 division vote on whether or not to initiate a reactor scram. Each chassis makes a divisional scram decision based on data from all sensors. Each division performs independently of the others (asynchronous operation). All communications between the divisions are asynchronous. Each chassis substitutes its own spare sensor reading in the 2/3 vote if a sensor reading from one of the other chassis is faulty or missing. Therefore the presence of at least two valid sensor readings in excess of a set point is required before terminating the output to the hardware logic of a scram inhibition signal even when one of the four sensors is faulty or when one of the divisions is out of service. 16 figs

  13. Thermal Protection Systems: Past, Present and Future

    Science.gov (United States)

    Johnson, Sylvia M.

    2015-01-01

    Thermal protection materials and systems (TPS) have been critical to fulfilling humankinds desire to explore space. Composite and ceramic materials have enabled the early missions to orbit, the moon, the space station, Mars with robots, and sample return. Crewed missions to Mars are being considered, and this places even more demands on TPS materials. This talk will give some history on the materials used for earth and planetary entry and the demands placed upon such materials. TPS needs for future missions, especially to Mars, will be identified and potential solutions discussed.

  14. Reactor protection system refurbishment at Paks

    International Nuclear Information System (INIS)

    Hetzmann, A.; Turi, T.

    1997-01-01

    The history and the milestones of the reactor protection system refurbishment are outlined. During the preparation phase of the refurbishment project, detailed requirements have been set up and specific technical solutions developed. The structure of the project documents prepared during these activities is shown in a figure. The life cycle of the project was divided into four phases: the preparatory phase; the design and manufacturing phase; the installation and commissioning phase; and the operation phase. For all four Paks units a time schedule for implementation was set up. The licensing process is dealt with; the principal license was issued in June 1996. (A.K.)

  15. Pneumatic Variable Series Elastic Actuator.

    Science.gov (United States)

    Zheng, Hao; Wu, Molei; Shen, Xiangrong

    2016-08-01

    Inspired by human motor control theory, stiffness control is highly effective in manipulation and human-interactive tasks. The implementation of stiffness control in robotic systems, however, has largely been limited to closed-loop control, and suffers from multiple issues such as limited frequency range, potential instability, and lack of contribution to energy efficiency. Variable-stiffness actuator represents a better solution, but the current designs are complex, heavy, and bulky. The approach in this paper seeks to address these issues by using pneumatic actuator as a variable series elastic actuator (VSEA), leveraging the compressibility of the working fluid. In this work, a pneumatic actuator is modeled as an elastic element with controllable stiffness and equilibrium point, both of which are functions of air masses in the two chambers. As such, for the implementation of stiffness control in a robotic system, the desired stiffness/equilibrium point can be converted to the desired chamber air masses, and a predictive pressure control approach is developed to control the timing of valve switching to obtain the desired air mass while minimizing control action. Experimental results showed that the new approach in this paper requires less expensive hardware (on-off valve instead of proportional valve), causes less control action in implementation, and provides good control performance by leveraging the inherent dynamics of the actuator.

  16. The Piezo Actuator-Driven Pulsed Water Jet System for Minimizing Renal Damage after Off-Clamp Laparoscopic Partial Nephrectomy.

    Science.gov (United States)

    Kamiyama, Yoshihiro; Yamashita, Shinichi; Nakagawa, Atsuhiro; Fujii, Shinji; Mitsuzuka, Koji; Kaiho, Yasuhiro; Ito, Akihiro; Abe, Takaaki; Tominaga, Teiji; Arai, Yoichi

    2017-09-01

    In the setting of partial nephrectomy (PN) for renal cell carcinoma, postoperative renal dysfunction might be caused by surgical procedure. The aim of this study was to clarify the technical safety and renal damage after off-clamp laparoscopic PN (LPN) with a piezo actuator-driven pulsed water jet (ADPJ) system. Eight swine underwent off-clamp LPN with this surgical device, while off-clamp open PN was also performed with radio knife or soft coagulation. The length of the removed kidney was 40 mm, and the renal parenchyma was dissected until the renal calyx became clearly visible. The degree of renal degeneration from the resection surface was compared by Hematoxylin-Eosin staining and immunostaining for 1-methyladenosine, a sensitive marker for the ischemic tissue damage. The mRNA levels of neutrophil gelatinase-associated lipocalin (Ngal), a biomarker for acute kidney injury, were measured by quantitative real-time PCR. Off-clamp LPN with ADPJ system was successfully performed while preserving fine blood vessels and the renal calix with little bleeding. In contrast to other devices, the resection surface obtained with the ADPJ system showed only marginal degree of ischemic changes. Indeed, the expression level of Ngal mRNA was lower in the resection surface obtained with the ADPJ system than that with soft coagulation (p = 0.02). Furthermore, using the excised specimens of renal cell carcinoma, we measured the breaking strength at each site of the human kidney, suggesting the applicability of this ADPJ to clinical trials. In conclusion, off-clamp LPN with the ADPJ system could be safely performed with attenuated renal damage.

  17. A road to practical dielectric elastomer actuators based robotics and mechatronics: discrete actuation

    Science.gov (United States)

    Plante, Jean-Sébastien; Devita, Lauren M.; Dubowsky, Steven

    2007-04-01

    Fundamental studies of Dielectric Elastomer Actuators (DEAs) using viscoelastic materials such as VHB 4905/4910 from 3M showed significant advantages at high stretch rates. The film's viscous forces increase actuator life and the short power-on times minimize energy losses through current leakage. This paper presents a design paradigm that exploits these fundamental properties of DEAs called discrete actuation. Discrete actuation uses DEAs at high stretch rates to change the states of robotic or mechatronic systems in discrete steps. Each state of the system is stable and can be maintained without actuator power. Discrete actuation can be used in robotic and mechatronic applications such as manipulation and locomotion. The resolution of such systems increases with the number of discrete states, 10 to 100 being sufficient for many applications. An MRI-guided needle positioning device for cancer treatments and a space exploration robot using hopping for locomotion are presented as examples of this concept.

  18. Extended DNA Tile Actuators

    DEFF Research Database (Denmark)

    Kristiansen, Martin; Kryger, Mille; Zhang, Zhao

    2012-01-01

    A dynamic linear DNA tile actuator is expanded to three new structures of higher complexity. The original DNA actuator was constructed from a central roller strand which hybridizes with two piston strands by forming two half-crossover junctions. A linear expansion of the actuator is obtained...

  19. Strain actuated aeroelastic control

    Science.gov (United States)

    Lazarus, Kenneth B.

    1992-01-01

    Viewgraphs on strain actuated aeroelastic control are presented. Topics covered include: structural and aerodynamic modeling; control law design methodology; system block diagram; adaptive wing test article; bench-top experiments; bench-top disturbance rejection: open and closed loop response; bench-top disturbance rejection: state cost versus control cost; wind tunnel experiments; wind tunnel gust alleviation: open and closed loop response at 60 mph; wind tunnel gust alleviation: state cost versus control cost at 60 mph; wind tunnel command following: open and closed loop error at 60 mph; wind tunnel flutter suppression: open loop flutter speed; and wind tunnel flutter suppression: closed loop state cost curves.

  20. ICI system for protecting underwater structures

    Energy Technology Data Exchange (ETDEWEB)

    1977-10-14

    The new ICI Offshore product consists of polypropylene fibers about 4.4 m long, and with a density lower than that of sea water and thus a good buoyancy coefficient. Bundles of the fibers are passed through a braided mat of polyester, ''Paraweb'', which is weighted in accordance with the density of the entire system. The system is installed at the foot of platform legs and axially along pipelines to prevent scouring by ocean currents. The system has been installed in 144.8 m of water along the pipeline linking the Piper field to the Flotta terminal in the Orkney Islands. By reducing the velocity of the marine currents, the system causes sand and other material to be deposited along the fibers, forming a protective ''talus'' cone at first, then completely covering the structure. A sizable sand deposit had accumulated along the test segment of the pipeline less than one month after installation of the system. Use of the system on the Ekofisk-Emden gas pipeline where it is uncovered in the Danish North Sea sector is proposed.

  1. Tubular permanent magnet actuators: cogging forces characterization

    NARCIS (Netherlands)

    Paulides, J.J.H.; Janssen, J.L.G.; Encica, L.; Lomonova, E.A.

    2009-01-01

    Tubular permanent magnet actuators are evermore used in demanding industrial and automotive applications. However, these actuators can suffer from large cogging forces, which have a destabilizing effect on the servo control system and compromise position and speed control accuracy. This paper

  2. Buckling Pneumatic Linear Actuators Inspired by Muscle

    OpenAIRE

    Yang, Dian; Verma, Mohit Singh; So, Ju-Hee; Mosadegh, Bobak; Keplinger, Christoph; Lee, Benjamin; Khashai, Fatemeh; Lossner, Elton Garret; Suo, Zhigang; Whitesides, George McClelland

    2016-01-01

    The mechanical features of biological muscles are difficult to reproduce completely in synthetic systems. A new class of soft pneumatic structures (vacuum-actuated muscle-inspired pneumatic structures) is described that combines actuation by negative pressure (vacuum), with cooperative buckling of beams fabricated in a slab of elastomer, to achieve motion and demonstrate many features that are similar to that of mammalian muscle.

  3. Privacy protection schemes for fingerprint recognition systems

    Science.gov (United States)

    Marasco, Emanuela; Cukic, Bojan

    2015-05-01

    The deployment of fingerprint recognition systems has always raised concerns related to personal privacy. A fingerprint is permanently associated with an individual and, generally, it cannot be reset if compromised in one application. Given that fingerprints are not a secret, potential misuses besides personal recognition represent privacy threats and may lead to public distrust. Privacy mechanisms control access to personal information and limit the likelihood of intrusions. In this paper, image- and feature-level schemes for privacy protection in fingerprint recognition systems are reviewed. Storing only key features of a biometric signature can reduce the likelihood of biometric data being used for unintended purposes. In biometric cryptosystems and biometric-based key release, the biometric component verifies the identity of the user, while the cryptographic key protects the communication channel. Transformation-based approaches only a transformed version of the original biometric signature is stored. Different applications can use different transforms. Matching is performed in the transformed domain which enable the preservation of low error rates. Since such templates do not reveal information about individuals, they are referred to as cancelable templates. A compromised template can be re-issued using a different transform. At image-level, de-identification schemes can remove identifiers disclosed for objectives unrelated to the original purpose, while permitting other authorized uses of personal information. Fingerprint images can be de-identified by, for example, mixing fingerprints or removing gender signature. In both cases, degradation of matching performance is minimized.

  4. Neutronic control instrumentation of protection systems

    International Nuclear Information System (INIS)

    Furet, J.

    1977-01-01

    The aims of neutronic control instrumentation are briefly recalled and the present status of materials research and development is presented. As for the out-of-pile instrumentation, emphasis is put on the reliability and efficiency of the detectors and the new solutions of electric signal processing. The possible reactivity measurements at rest are examined. As for in-pile instrumentation results relating to mobile detectors of the type of miniaturized fission chambers are presented. The radiation tests on course of development for several years in the working conditions of neutron self-powdered detectors are analyzed so as to show that their use as built-in in-core instrumentation is to be envisaged at short term. Basic options inherent to the 'Nuclear Safety' philosophy that define the protection system are recalled. A definition and a justification of the performance testing of the instrumentation at rest and in-service are then derived. Some new solutions are envisaged for processing the digital data obtained from the various sensors . A quality control of the materials setting conditions (especially electric noise) ensures a high reliability and availability of the materials involved in the neutron control and the protection system in working conditions [fr

  5. 3D Multifunctional Ablative Thermal Protection System

    Science.gov (United States)

    Feldman, Jay; Venkatapathy, Ethiraj; Wilkinson, Curt; Mercer, Ken

    2015-01-01

    NASA is developing the Orion spacecraft to carry astronauts farther into the solar system than ever before, with human exploration of Mars as its ultimate goal. One of the technologies required to enable this advanced, Apollo-shaped capsule is a 3-dimensional quartz fiber composite for the vehicle's compression pad. During its mission, the compression pad serves first as a structural component and later as an ablative heat shield, partially consumed on Earth re-entry. This presentation will summarize the development of a new 3D quartz cyanate ester composite material, 3-Dimensional Multifunctional Ablative Thermal Protection System (3D-MAT), designed to meet the mission requirements for the Orion compression pad. Manufacturing development, aerothermal (arc-jet) testing, structural performance, and the overall status of material development for the 2018 EM-1 flight test will be discussed.

  6. Extensions and renovations of reactor protection systems

    International Nuclear Information System (INIS)

    Hellmerichs, K.

    1985-01-01

    Increase of requirements by the authorities as to the design of reactor protection systems affected in the last years not only plans being under construction, but also resulted in partly spacious extensions and renovations. While working on the extensions and renovations a lot of problems arose: far-reaching performance of newest guidelines and rules in spite of old plant concepts; partly higher degree of redundancy requirements of the new systems in contrast to the present systems; use of present safeguard systems for new accident countermeasures; designation of priorities between present and new functions, especially in view of fault behaviour of present systems; adaptation of the new I and C equipment to the present signalisation-, operation- and information-arrangements under consideration of the present operational philosophy; spatial incorporation of new equipments; construction as to time without expanding of the planned refuelling phases. Because the KWU has planned and constructed such alterations in nearly 10 plants a lot of experience has been gathered. (author)

  7. Physical protection system using activated barriers

    International Nuclear Information System (INIS)

    Timm, R.E.; Zinneman, T.E.; Haumann, J.R.; Flaugher, H.A.; Reigle, D.L.

    1984-03-01

    The Argonne National Laboratory has recently installed an activated barrier, the Access Denial System, to upgrade its security. The technology of this system was developed in the late 70's by Sandia National Laboratory-Albuquerque. The Argonne National Laboratory is the first Department of Energy facility to use this device. Recent advancements in electronic components provide the total system support that makes the use of an activated barrier viable and desirable. The premise of an activated barrier is that it is deployed after a positive detection of an adversary is made and before the adversary can penetrate vital area. To accomplish this detection, sophisticated alarms, assessment, and communications must be integrated into a system that permits a security inspector to make a positive evaluation and to activate the barrier. The alarm sensor locations are selected to provide protection in depth. Closed circuit television is used with components that permit multiple video frames to be stored for automated, priority-based playback to the security inspector. Further, algorithms permit look-ahead surveillance of vital areas so that the security inspector can activate the access denial system in a timely manner and not be restricted to following the adversaries' penetration path(s)

  8. Electro-optic architecture for servicing sensors and actuators in advanced aircraft propulsion systems

    Science.gov (United States)

    Poppel, G. L.; Glasheen, W. M.

    1989-01-01

    A detailed design of a fiber optic propulsion control system, integrating favored sensors and electro-optics architecture is presented. Layouts, schematics, and sensor lists describe an advanced fighter engine system model. Components and attributes of candidate fiber optic sensors are identified, and evaluation criteria are used in a trade study resulting in favored sensors for each measurand. System architectural ground rules were applied to accomplish an electro-optics architecture for the favored sensors. A key result was a considerable reduction in signal conductors. Drawings, schematics, specifications, and printed circuit board layouts describe the detailed system design, including application of a planar optical waveguide interface.

  9. Single-crystal-material-based induced-shear actuation for vibration reduction of helicopters with composite rotor system

    International Nuclear Information System (INIS)

    Pawar, Prashant M; Jung, Sung Nam

    2008-01-01

    In this study, an assessment is made for the helicopter vibration reduction of composite rotor blades using an active twist control concept. Special focus is given to the feasibility of implementing the benefits of the shear actuation mechanism along with elastic couplings of composite blades for achieving maximum vibration reduction. The governing equations of motion for composite rotor blades with surface bonded piezoceramic actuators are obtained using Hamilton's principle. The equations are then solved for dynamic response using finite element discretization in the spatial and time domains. A time domain unsteady aerodynamic theory with free wake model is used to obtain the airloads. A newly developed single-crystal piezoceramic material is introduced as an actuator material to exploit its superior shear actuation authority. Seven rotor blades with different elastic couplings representing stiffness properties similar to stiff-in-plane rotor blades are used to investigate the hub vibration characteristics. The rotor blades are modeled as a box beam with actuator layers bonded on the outer surface of the top and bottom of the box section. Numerical results show that a notable vibration reduction can be achieved for all the combinations of composite rotor blades. This investigation also brings out the effect of different elastic couplings on various vibration-reduction-related parameters which could be useful for the optimal design of composite helicopter blades

  10. Single-crystal-material-based induced-shear actuation for vibration reduction of helicopters with composite rotor system

    Science.gov (United States)

    Pawar, Prashant M.; Jung, Sung Nam

    2008-12-01

    In this study, an assessment is made for the helicopter vibration reduction of composite rotor blades using an active twist control concept. Special focus is given to the feasibility of implementing the benefits of the shear actuation mechanism along with elastic couplings of composite blades for achieving maximum vibration reduction. The governing equations of motion for composite rotor blades with surface bonded piezoceramic actuators are obtained using Hamilton's principle. The equations are then solved for dynamic response using finite element discretization in the spatial and time domains. A time domain unsteady aerodynamic theory with free wake model is used to obtain the airloads. A newly developed single-crystal piezoceramic material is introduced as an actuator material to exploit its superior shear actuation authority. Seven rotor blades with different elastic couplings representing stiffness properties similar to stiff-in-plane rotor blades are used to investigate the hub vibration characteristics. The rotor blades are modeled as a box beam with actuator layers bonded on the outer surface of the top and bottom of the box section. Numerical results show that a notable vibration reduction can be achieved for all the combinations of composite rotor blades. This investigation also brings out the effect of different elastic couplings on various vibration-reduction-related parameters which could be useful for the optimal design of composite helicopter blades.

  11. 46 CFR 154.1110 - Areas protected by system.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Areas protected by system. 154.1110 Section 154.1110... Firefighting § 154.1110 Areas protected by system. Each water spray system must protect: (a) All cargo tank... valves essential to cargo flow; (f) Each boundary facing the cargo area of each superstructure that...

  12. 46 CFR 153.460 - Fire protection systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Fire protection systems. 153.460 Section 153.460... Requirements for Flammable Or Combustible Cargoes § 153.460 Fire protection systems. Each self-propelled ship... protection system listed beside the cargo in Table 1 and described in the footnotes to Table 1. (b) The...

  13. Control Reconfiguration of LPV Systems Using Virtual Sensor and Virtual Actuator

    DEFF Research Database (Denmark)

    Tabatabaeipour, Seyed Mojtaba; Stoustrup, Jakob; Bak, Thomas

    2012-01-01

    the plant and the nominal controller such that the fault tolerant goal is achieved without re-designing the nominal controller. The role of the reconfiguration block is to transform the signals from the faulty system such that its behavior is similar to the nominal system from the point of view...

  14. Digital signal processing in power system protection and control

    CERN Document Server

    Rebizant, Waldemar; Wiszniewski, Andrzej

    2011-01-01

    Digital Signal Processing in Power System Protection and Control bridges the gap between the theory of protection and control and the practical applications of protection equipment. Understanding how protection functions is crucial not only for equipment developers and manufacturers, but also for their users who need to install, set and operate the protection devices in an appropriate manner. After introductory chapters related to protection technology and functions, Digital Signal Processing in Power System Protection and Control presents the digital algorithms for signal filtering, followed

  15. An Evolved System of Radiological Protection

    International Nuclear Information System (INIS)

    Kaneko, M.

    2004-01-01

    The current system of radiological protection based on the Linear No-Threshold (LNT) hypothesis has greatly contributed to the minimization of doses received by workers and members of the public. However, it has brought about r adiophobia a mong people and waste of resources due to over-regulation, because the LNT implies that radiation is harmful no matter how small the dose is. The author reviewed the results of research on health effects of radiation including major epidemiological studies on radiation workers and found no clear evidence of deleterious health effects from radiation exposures below the current maximum dose limits (50 mSv/y for workers and 5 mSv/y for members of the public), which have been adopted worldwide in the second half of the 20th century. Now that the existence of bio-defensive mechanisms such as DNA repair, apoptosis and adaptive response are well recognized, the linearity assumption cannot be said to be s cientific . Evidences increasingly imply that there are threshold effects in risk of radiation. A concept of practical thresholds or virtually safe doses will have to be introduced into the new system of radiological protection in order to resolve the low dose issues. Practical thresholds may be defined as dose levels below which induction of detectable radiogenic cancers or hereditary effects are not expected. If any workers and members of the public do not gain benefits from being exposed, excepting intentional irradiation for medical purposes, their radiation exposures should be kept below practical thresholds. On the assumption that the current dose limits are below practical thresholds and with no radiation detriments, there is no need of justification and optimization (ALARA) principles for occupational and public exposures. Then the ethical issue of justification to allow benefit to society to offset radiation detriments to individuals can be resolved. And also the ethical issue of optimization to exchange health or safety for

  16. Diversity in computerized reactor protection systems

    International Nuclear Information System (INIS)

    Fischer, H.D.; Piel, L.

    1999-01-01

    Based on engineering judgement, the most important measures to increase the independency of redundant trains of a computerized safety instrumentation and control system (I and C) in a nuclear power plant are evaluated with respect to practical applications. This paper will contribute to an objective discussion on the necessary and justifiable arrangement of diversity in a computerized safety I and C system. Important conclusions are: - (i) diverse equipment may be used to control dependent failures only if measures necessary for designing, licensing, and operating a computerized safety I and C system homogeneous in equipment are neither technically nor economically feasible; - (ii) the considerable large operating experience in France with a non-diverse equipment digital reactor protection system does not call for equipment diversity. Although there are no generally accepted methods, the licensing authority is still required to take into account dependent failures in a probabilistic safety analysis; - (ii) the frequency of postulated initiating events implies which I and C functionality should be implemented on diverse equipment. Using non-safety I and C equipment in addition to safety I and C equipment is attractive because its necessary unavailability to control an initiating event in teamwork with the safety I and C equipment is estimated to range from 0.01 to 0.1. This can be achieved by operational experience

  17. Evolution of the system of radiological protection

    International Nuclear Information System (INIS)

    2007-01-01

    The OECD Nuclear Energy Agency (NEA) has actively participated in discussions with the International Commission on Radiological Protection (ICRP) regarding the development of new recommendations that will replace those in ICRP Publication 60, which has long served as the international standard in this field. Part of this development process has involved the organisation of seven international workshops, including the First and Second Asian Regional Conferences on the Evolution of the System of Radiological Protection which took place in Tokyo, Japan in October 2002 and July 2004. The Third Asian Regional Conference was held on 5-6 July 2006, also in Tokyo. The main objective of these conferences was to ensure that the views and concerns of relevant Asian stakeholders, such as regulatory authorities, industry, professional societies and NGO, could be expressed and discussed with the ICRP. The three conferences provided the ICRP with specific views on how new recommendations could best be developed to address regulatory and implementation needs in the Asian context. These proceedings summarize the results and key discussions of the Third Asian Regional Conference. (author)

  18. Integration of the environment into the system of radiation protection

    International Nuclear Information System (INIS)

    Higley, K.

    2018-01-01

    In 2005 the International Commission on Radiological Protection (ICRP) embarked on an effort to ensure that the system for environmental radiological protection would be reconcilable with that for radiological protection of man, and with the approaches used for protection of the environment from other potential hazards

  19. An H-module linear actuator for medical equipment applications

    DEFF Research Database (Denmark)

    Liu, Xiao; Wu, Keyuan; ye, yunyue

    2012-01-01

    An H-module linear actuator (HMLA) is proposed in this paper for medical equipment applications. Compared to the existing linear actuators used in medical equipment, the proposed H-module linear actuator has much lower normal force, which makes use of an additional air-suspension system unnecessary...

  20. Adaptive Fault-Tolerant Tracking Control of Nonaffine Nonlinear Systems with Actuator Failure

    Directory of Open Access Journals (Sweden)

    Hongcheng Zhou

    2014-01-01

    Full Text Available This paper proposes an adaptive fault-tolerant control scheme for nonaffine nonlinear systems. A model approximation method which is a solution that bridges the gap between affine and nonaffine control systems is developed firstly. A joint estimation approach is based on unscented Kalman filter, in which both failure parameters and states are simultaneously estimated by means of the argument state vector composed of the unknown faults and states. Then, stability analysis is given for the closed-loop system. Finally, the proposed approach is verified using a three-degree-of-freedom simulation of a typical fighter aircraft and the significantly improved system response demonstrates the practical potential of the theoretic results obtained.