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Piezoelectric ultrasonic actuators

Schematic of the linear piezoelectric ultrasonic actuator (adapted from Friend et al., 2008)... Schematic of the linear piezoelectric ultrasonic actuator (adapted from Friend et al., 2008)...
Chemical and physical processing techniques for ferroelectric thin films have undergone explosive advancement in the past few years (see Ref. 1, for example). The use of PZT (PbZri- cTi c03) family ferroelectrics in the nonvolatile and dynamic random access memory applications present potentially large markets [2]. Other thin-film devices based on a wide variety of ferroelectrics have also been explored. These include multilayer thin-film capacitors [3], piezoelectric or electroacoustic transducer and piezoelectric actuators [4-6], piezoelectric ultrasonic micromotors [7], high-frequency surface acoustic devices [8,9], pyroelectric intrared (IR) detectors [10-12], ferroelectric/photoconduc-tive displays [13], electrooptic waveguide devices or optical modulators [14], and ferroelectric gate and metal/insulator/semiconductor transistor (MIST) devices [15,16]. [Pg.481]

Following a principle used in piezoelectric ultrasonic motors [60], T. Aku-ta [61] has built the first magnetostrictive friction motor. This stator is made of pairs of orthogonal actuators excited with sinusoidal 90° phase-shift currents, which produce an elliptical vibration. The modeling of such magnetostrictive stators [42] has shown that in quasi-static operation a good elliptical motion is produced. It has also been shown that there are many coupled modes, but none of them provides a satisfactory elliptical motion. Therefore, unlike piezoelectric motors, this motor cannot operate at resonance. As a consequence and in relation to the previous analysis of power (Fig. 6.34), the efficiency is comparatively weak. Its other characteristics are a speed of 40°/s and a torque of 1.8 Nm [62]. [Pg.140]

Friend, J., Yeo, L. and Hogg, M. (2008) Piezoelectric ultrasonic bidirectional linear actuator for micropositioning fulfilling Feynman s criteria . Applied Physics Letters, 92, 014107. [Pg.96]

Watson, B., Friend, J. and Yeoa, L. (2009) Piezoelectric ultrasonic micro/milli-scale actuators , Sensors and Actuators A Physical, 152(2) 219-33. [Pg.98]

Zhang et al. [83,84] have shown theoretically that the basic elastic coupling mechanism between the two componeata b the 2>2 piezoelectric composite is similar to that of the 1-3 composite, although the 2-2 structure b not widely us There ate two major areas where 1-3 composites have been widely used underwater hydrophone applications and ultrasonic actuators and sensors for medical dUgnostk devices [15,16,24,8334]. [Pg.545]

Another important class of titanates that can be produced by hydrothermal synthesis processes are those in the lead zirconate—lead titanate (PZT) family. These piezoelectric materials are widely used in manufacture of ultrasonic transducers, sensors, and minia ture actuators. The electrical properties of these materials are derived from the formation of a homogeneous soHd solution of the oxide end members. The process consists of preparing a coprecipitated titanium—zirconium hydroxide gel. The gel reacts with lead oxide in water to form crystalline PZT particles having an average size of about 1 ]lni (Eig. 3b). A process has been developed at BatteUe (Columbus, Ohio) to the pilot-scale level (5-kg/h). [Pg.500]

Sonic Methods A fixed-point level detector based on sonic-propagation characteristics is available for detection of a liquid-vapor interface. This device uses a piezoelectric transmitter and receiver, separated by a short gap. When the gap is filled with liquid, ultrasonic energy is transmitted across the gap, and the receiver actuates a relay. With a vapor filling the gap, the transmission of ultrasonic energy is insufficient to actuate the receiver. [Pg.764]

Uchino, K. (1997) Piezoelectric Actuators and Ultrasonic Motors, Kluwer Academic Publishers, London. [Pg.410]

Uchino K (1996) Piezoelectric actuators and ultrasonic motors. Kluver Academic, Boston... [Pg.162]

Relaxor-type electrostrictive materials, such as those from the lead magnesium niobate-lead titanate, Pb(Mgp 3Nb2/3)03-PbTi03 (or PMN-PT), solid solution are highly suitable for actuator applications. This relaxor ferroelectric also exhibits an induced piezoelectric effect. That is, the electromechanical coupling factor kt varies with the applied DC bias field. As the DC bias field increases, the coupling increases and saturates. Since this behavior is reproducible, these materials can be applied as ultrasonic transducers which are tunable by the bias field [12]. [Pg.115]

Piezoelectric and electrostrictive devices have become key components in smart actuator systems such as precision positioners, miniature ultrasonic motors and adaptive mechanical dampers. This section reviews the developments of piezoelectric and related ceramic actuators with particular focus on the improvement of actuator materials, device designs and applications of the actuators. [Pg.133]

Tabib-Azar M (1998) Microactuators, electrical, magnetic, thermal, optical, mechanical, chemical and smart structures. Kluwer, Norwell, MA Uchino K (1997) Piezoelectric actuators and ultrasonic motors. Kluwer, Norwell, MA Uchino K (2000) Ferroelectric devices, Marcel Dekker, New York... [Pg.1]

The high polarizabilities of the TiOg-octahedra results in anomalously high values of the dielectric permittivities (see Figure 8.2), as well as the electro-optical, nonlinear optical, piezoelectric and electromechanical coupling coefficients (Cross, 1993). This is at the very heart of the technical application of ferroelectric materials as ultrasonic oscillators, acoustic and optical frequency multipliers, dielectric amplifiers, acoustic and optical frequency modulators, switches, sensors, actuators, and many more. For detailed accounts on these applications, see Uchino (1994, 1996), Cross (1993), and Heywang et al. (2009). [Pg.266]

Uchino, K. (1995) Piezoelectric Actuators and Ultrasonic Motors. Electronic Materials Science Technology (ed. H.L. Tuller), Kluwer Academic Publ., Deventer. ISBN 978-07923-98-11-0, 354 pp. [Pg.317]


See other pages where Piezoelectric ultrasonic actuators is mentioned: [Pg.71]    [Pg.209]    [Pg.349]    [Pg.194]    [Pg.292]    [Pg.502]    [Pg.34]    [Pg.1242]    [Pg.324]    [Pg.460]    [Pg.193]    [Pg.115]    [Pg.116]    [Pg.134]    [Pg.5693]    [Pg.10]    [Pg.348]    [Pg.455]    [Pg.19]    [Pg.222]    [Pg.211]    [Pg.361]   
See also in sourсe #XX -- [ Pg.69 , Pg.70 ]




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Piezoelectric actuators

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