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Closed loop control systems employing relaxor ferroelectric actuators

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TLDR
In this article, a closed loop motion control system employing at least one relaxor actuator which controls the position of a moving member having mass by controlling an electric field applied to the actuator is described.
Abstract
A closed loop motion control system employing at least one relaxor actuator which controls the position of a moving member having mass by controlling an electric field applied to the relaxor actuator. The actuator comprises a body of relaxor material dimensionally variable under the influence of the electric field applied in the form of a voltage to electrodes on at least two surfaces of the actuator. The voltage is applied in response to a feedback signal produced by at least one feedback sensor, which may be a displacement sensor or some other type of sensor. Thus, by constantly monitoring the displacement or other variable of the actuator device, the position of the moving member may be precisely controlled.

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Citations
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References
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Journal ArticleDOI

Ultrahigh strain and piezoelectric behavior in relaxor based ferroelectric single crystals

TL;DR: In this article, the piezoelectric properties of relaxor based ferroelectric single crystals, such as Pb(Zn1/3Nb2/3)O3 and PbTiO3, were investigated for electromechanical actuators.
Journal ArticleDOI

High performance single crystal piezoelectrics: applications and issues

TL;DR: Relaxor-based single crystal piezoelectrics began to live up to their promise of providing unprecedented increase of bandwidth, sensitivity, and high energy density for advanced P2P transducers and actuator applications as mentioned in this paper.
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Packaged strain actuator

TL;DR: A modulator actuator assembly includes one or more plates or elements of electroactive material (71, 73) bonded to an electroded sheet to form a card as discussed by the authors, which may itself constitute a practical device, such as a vane, shaker, stirrer, lever, pusher or sonicator for direct contact with a solid or immersion in a fluid.
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Three dimensionally periodic structural assemblies on nanometer and longer scales

TL;DR: In this paper, the assembly of three-dimensional structures having periodicities on the scale of optical wavelengths, and at both smaller and larger dimensions, as well as compositions and applications are described.
PatentDOI

Ultrasonic phased array transducer with an ultralow impedance backfill and a method for making

TL;DR: In this paper, an ultrasonic phased array transducer with an ultralow backfill and a method for making is described. But the backfill material is either an aerogel or a carbon xerogel.
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