A comparative study of ultrasonic micro-motors based on single crystal PMN-PT and polycrystalline PZT ceramics

Stephen A. Wilson, Philip J. Rayner, John Gore, Adrian R. Bowles, Richard C. McBride

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

    1 Citation (Scopus)


    A comparative study has been made to explore the potential benefits of newly available single-crystal ferroelectric materials when used in a practical device, in this case an ultrasonic micro-motor. This type of micro-motor exhibits exceptional power-to-weight characteristics, which could be exploited beneficially, for example, in unmanned air-vehicle (UAV) systems. The operating principles of a range of commercial and experimental motor designs were evaluated objectively in order to identify areas of performance that can potentially be enhanced using PMN-PT single-crystal piezoelectric ceramics. Based on this analysis a practical motor design was selected for construction and experimentation. Detailed numerical analysis indicated that a motor constructed from single crystal PMN-PT could be expected to provide an improvement in motor stall-torque by up to a factor of 2.8 and a no-load speed improvement by a factor of 1.5 when compared with motors based on standard polycrystalline lead-zirconate-titanate (PZT) ceramics. In practice single-crystal versions of the motor were found to produce double the power output of their polycrystalline counterparts. Overall efficiency was found to be improved two-fold. There were significant discrepancies between the numerical predictions for the single-crystal devices and their measured performance, whereas the polycrystalline devices were found to perform closely in line with predictions.

    Original languageEnglish
    Title of host publicationIndustrial and Commercial Applications af Smart Structures Technologies 2008
    EditorsL. Porter Davis, Benjamin K. Henderson, M. Brett McMickell
    Place of PublicationBellingham
    PublisherSPIE-International Society for Optical Engineering
    ISBN (Print)9780819471161
    Publication statusPublished - 2008
    EventSPIE Smart Structures/NDE 2008: Industrial and Commercial Applications of Smart Structures Technologies II - Town and Country Resort & Convention Center, San Diego, United States
    Duration: 10 Mar 200811 Mar 2008

    Publication series

    NameProceedings of SPIE


    ConferenceSPIE Smart Structures/NDE 2008: Industrial and Commercial Applications of Smart Structures Technologies II
    CountryUnited States
    CitySan Diego
    Other15th Annual International Symposium on Smart Structures and Materials & Nondestructive Evaluation and Health Monitoring
    Internet address

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