Can a coupling coefficient of a piezoelectric device be higher than those of its active material?

George A. Lesieutre, Christopher L. Davis

Research output: Chapter in Book/Report/Conference proceedingConference contribution

11 Citations (Scopus)

Abstract

A coupling coefficient is a measure of the effectiveness with which a shape-changing material (or a device employing such a material) converts the energy in an imposed signal to useful mechanical energy. There are different kinds of material and device coupling coefficients, corresponding to different modes of excitation and response. Device coupling coefficients are properties of the device and, although related to the material coupling coefficients, are generally different from them. It is commonly held that a device coupling coefficient cannot be greater than some corresponding coupling coefficient of the active material used in the device. A class of devices was recently identified in which the apparent coupling coefficient can, in principle, approach 1.0, corresponding to perfect electromechanical energy conversion. The key feature of this class of devices is the use of destabilizing mechanical pre- loads to counter inherent stiffness. The approach is illustrated for a piezoelectric bimorph device: theory predicts a smooth increase of the apparent coupling coefficient with pre-load, approaching 1.0 at the buckling load. An experiment verified the trend of increasing coupling with pre-load. This approach provides a way to simultaneously increase both displacement and force, distinguishing it from alternatives such as motion amplification, and may allow transducer designers to achieve substantial performance gains for some actuator and sensor devices.

Original languageEnglish (US)
Title of host publicationProceedings of SPIE - The International Society for Optical Engineering
PublisherSociety of Photo-Optical Instrumentation Engineers
Pages281-292
Number of pages12
Volume3041
ISBN (Print)0819424544
StatePublished - 1997
EventSmart Structures and Materials 1997: Smart Structures and Integrated Systems - San Diego, CA, USA
Duration: Mar 3 1997Mar 6 1997

Other

OtherSmart Structures and Materials 1997: Smart Structures and Integrated Systems
CitySan Diego, CA, USA
Period3/3/973/6/97

Fingerprint

Piezoelectric devices
coupling coefficients
Energy conversion
Buckling
Amplification
Transducers
Loads (forces)
Actuators
Stiffness
Sensors
energy conversion
buckling
stiffness
transducers
counters
actuators
Experiments

All Science Journal Classification (ASJC) codes

  • Electrical and Electronic Engineering
  • Condensed Matter Physics

Cite this

Lesieutre, G. A., & Davis, C. L. (1997). Can a coupling coefficient of a piezoelectric device be higher than those of its active material? In Proceedings of SPIE - The International Society for Optical Engineering (Vol. 3041, pp. 281-292). Society of Photo-Optical Instrumentation Engineers.
Lesieutre, George A. ; Davis, Christopher L. / Can a coupling coefficient of a piezoelectric device be higher than those of its active material?. Proceedings of SPIE - The International Society for Optical Engineering. Vol. 3041 Society of Photo-Optical Instrumentation Engineers, 1997. pp. 281-292
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Lesieutre, GA & Davis, CL 1997, Can a coupling coefficient of a piezoelectric device be higher than those of its active material? in Proceedings of SPIE - The International Society for Optical Engineering. vol. 3041, Society of Photo-Optical Instrumentation Engineers, pp. 281-292, Smart Structures and Materials 1997: Smart Structures and Integrated Systems, San Diego, CA, USA, 3/3/97.

Can a coupling coefficient of a piezoelectric device be higher than those of its active material? / Lesieutre, George A.; Davis, Christopher L.

Proceedings of SPIE - The International Society for Optical Engineering. Vol. 3041 Society of Photo-Optical Instrumentation Engineers, 1997. p. 281-292.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Lesieutre GA, Davis CL. Can a coupling coefficient of a piezoelectric device be higher than those of its active material? In Proceedings of SPIE - The International Society for Optical Engineering. Vol. 3041. Society of Photo-Optical Instrumentation Engineers. 1997. p. 281-292