Active Fiber

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 29253 Experts worldwide ranked by ideXlab platform

Andreas J. Brunner - One of the best experts on this subject based on the ideXlab platform.

  • Active Fiber composites for the generation of Lamb waves.
    Ultrasonics, 2008
    Co-Authors: M. Birchmeier, Andreas J. Brunner, Daniel Gsell, M. Juon, R. Paradies, Jürg Dual
    Abstract:

    Active Fiber composites (AFC) are thin and conformable transducer elements with orthotropic material properties, since they are made of one layer of piezoelectric ceramic Fibers. They are suitable for applications in structural health monitoring systems (SHM) with acoustic non-destructive testing methods (NDT). In the presented work the transfer behavior of an AFC as an emitter of transient elastic waves in plate-like structures is investigated. The wave field emitted by an AFC surface bonded on an isotropic plate was simulated with the finite-difference method. The model includes the piezoelectric element and the plate and allows the simulation of the elastic wave propagation. For comparison with the model experiments using a laser interferometer for non-contact measurements of particle velocities at different points around the AFC on the surface of the plate were performed. Transfer functions defined as the ratio of the electric voltage excitation signal and the resulting surface velocity at a specific point are separately determined for the two fundamental Lamb wave modes. In order to take the orthotropic behavior of the AFC into account the transfer functions are determined for several points around the AFC. Results show that the AFC is capable to excite the fundamental symmetric and antisymmetric Lamb wave mode. The antisymmetric mode is mainly radiated in the direction of the piezoelectric Fibers, while the symmetric mode is spread over a larger angle. The amplitudes of the emitted waves depend on the frequency of the excitation as well as on the geometric dimensions of the transducer.

  • Integrated Active Fiber Composite Elements: Characterization for Acoustic Emission and Acousto-ultrasonics:
    Journal of Intelligent Material Systems and Structures, 2006
    Co-Authors: Michel Barbezat, Andreas J. Brunner, Christian Huber, Peter Flüeler
    Abstract:

    Active Fiber composites (AFC) made from piezoelectric Fibers show promising potential, not only as actuators integrated into smart composites but also as sensors. Selected sensor properties of AFC elements are investigated with methods from acoustic emission sensor characterization and verification and from acousto-ultrasonic testing. Model experiments with AFC elements integrated in simple composite structures show that the various approaches for analysis of acousto-ultrasonic data yield indications of damage accumulation.

  • The potential of Active Fiber composites made from piezoelectric Fibers for actuating and sensing applications in structural health monitoring
    Materials and Structures, 2005
    Co-Authors: Andreas J. Brunner, Ch. Huber, Michel Barbezat, P. H. Flüeler
    Abstract:

    Des Composites à Fibres Actifs constitués de fibres piézo-électriques ont été développés initialement comme actuateurs pour des systèmes adaptifs. Les propriétés des Composites Actifs à Fibres permettent également leur application comme capteur ou émetteurcapteur. Après une discussion de certaines de leurs caractéristiques, le potentiel des Composites à Fibres Actifs pour le contrôle de santé structurale sera discuté en comparaison avec des éléments piézo-électriques conventionnels. Active Fiber Composites made from piezoelectric Fibers were originally developed as actuators for adaptive materials systems. Their properties, however, also allow their use as sensor or emitter-receiver in variours applications. After presenting selected characteristics, the potential of Active Fiber Composites for structural health monitoring is discussed in comparison with that of conventional piezoelectric elements.

  • The potential of Active Fiber composites made from piezoelectric Fibers for actuating and sensing applications in structural health monitoring
    Materials and Structures Materiaux et Constructions, 2005
    Co-Authors: Andreas J. Brunner, Ch. Huber, Michel Barbezat, P. H. Fl??eler
    Abstract:

    Active Fiber Composites made from piezoelectric Fibers were originally developed as actuators for adaptive materials systems. Their properties, however, also allow their use as sensor or emitter-receiver in various applications. After presenting selected characteristics, the potential of Active Fiber Composites for structural health monitoring is discussed in comparison with that of conventional piezoelectric elements.

Michel Barbezat - One of the best experts on this subject based on the ideXlab platform.

  • Integrated Active Fiber Composite Elements: Characterization for Acoustic Emission and Acousto-ultrasonics:
    Journal of Intelligent Material Systems and Structures, 2006
    Co-Authors: Michel Barbezat, Andreas J. Brunner, Christian Huber, Peter Flüeler
    Abstract:

    Active Fiber composites (AFC) made from piezoelectric Fibers show promising potential, not only as actuators integrated into smart composites but also as sensors. Selected sensor properties of AFC elements are investigated with methods from acoustic emission sensor characterization and verification and from acousto-ultrasonic testing. Model experiments with AFC elements integrated in simple composite structures show that the various approaches for analysis of acousto-ultrasonic data yield indications of damage accumulation.

  • The potential of Active Fiber composites made from piezoelectric Fibers for actuating and sensing applications in structural health monitoring
    Materials and Structures, 2005
    Co-Authors: Andreas J. Brunner, Ch. Huber, Michel Barbezat, P. H. Flüeler
    Abstract:

    Des Composites à Fibres Actifs constitués de fibres piézo-électriques ont été développés initialement comme actuateurs pour des systèmes adaptifs. Les propriétés des Composites Actifs à Fibres permettent également leur application comme capteur ou émetteurcapteur. Après une discussion de certaines de leurs caractéristiques, le potentiel des Composites à Fibres Actifs pour le contrôle de santé structurale sera discuté en comparaison avec des éléments piézo-électriques conventionnels. Active Fiber Composites made from piezoelectric Fibers were originally developed as actuators for adaptive materials systems. Their properties, however, also allow their use as sensor or emitter-receiver in variours applications. After presenting selected characteristics, the potential of Active Fiber Composites for structural health monitoring is discussed in comparison with that of conventional piezoelectric elements.

  • The potential of Active Fiber composites made from piezoelectric Fibers for actuating and sensing applications in structural health monitoring
    Materials and Structures Materiaux et Constructions, 2005
    Co-Authors: Andreas J. Brunner, Ch. Huber, Michel Barbezat, P. H. Fl??eler
    Abstract:

    Active Fiber Composites made from piezoelectric Fibers were originally developed as actuators for adaptive materials systems. Their properties, however, also allow their use as sensor or emitter-receiver in various applications. After presenting selected characteristics, the potential of Active Fiber Composites for structural health monitoring is discussed in comparison with that of conventional piezoelectric elements.

P. H. Fl??eler - One of the best experts on this subject based on the ideXlab platform.

Jung-ryul Lee - One of the best experts on this subject based on the ideXlab platform.

  • Ultrasonic Active Fiber Sensor based on Pulse-echo Method
    Journal of Intelligent Material Systems and Structures, 2008
    Co-Authors: Seung-hyun Lim, Jung-ryul Lee
    Abstract:

    In this study, the concept of the ultrasonic Active Fiber sensor (UAFS) system based on the pulse-echo method was newly proposed for several mechanical and environmental sensors. A piezoelectric transducer, which was attached onto the end of the optical Fiber, can be used for the ultrasonic wave generator and receiver. The piezoelectric patch was excited at its resonance frequency in the direction of length to generate the longitudinal ultrasonic wave, and was used for sensing the reflected signal on the end of the optical Fiber. The emitted ultrasonic wave was propagated along the optical Fiber and then reflected by a mechanical stimulus on the way. The time interval of the reflected ultrasonic wave was used to predict the location of the stimulus from the piezoelectric transducer. The UAFS was applied to monitor the cure conditions and to measure liquid level. In terms of the attenuation of the ultrasonic wave by the damping properties and the degree of coupling between the surrounding medium, the cure condition of the solder was successfully monitored and the water level was measured based on the linear relationship between liquid height and output signal.

Xinzhi Sheng - One of the best experts on this subject based on the ideXlab platform.

  • Optical Packet Replicator Using Cascaded SOA-Based Active Fiber Ring
    IEEE Photonics Technology Letters, 2009
    Co-Authors: Yaping Wang, Yongjun Wang, Zhi Wang, Xinzhi Sheng
    Abstract:

    The optical packet replicator using a cascaded semiconductor optical amplifier (SOA)-based Active Fiber ring is proposed. By introducing the noncircular assistant light into each stage and adopting a two-stage cascaded structure, 100 replications with identity amplitude are realized. Due to accumulation of amplified spontaneous emission noise, the output signal-to-noise ratio (SNR) of the 100th replication degrades 3.8 dB, which is equivalent to the SNR degradation of 19th replication in a single ring. The number of replications can be controlled by configuring driving pulses of SOA and each interval of hundreds of replications is equal accurately. It can be employed in ultraspeed sampling without any phase jitter.