Friction drive of an SAW motor. Part II: Analyses

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 55; no. 9; pp. 2016 - 2024
• Main Authors: Shigematsu, T., Kurosawa, M.K.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-09-2008; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acoustics; Acoustics - instrumentation; Anisotropic magnetoresistance; Approximation methods; Boundary conditions; Computer-Aided Design; Contact; Crystalline materials; Crystallization; Dynamic tests; Dynamics; Educational technology; Energy Transfer; Equipment Design; Equipment Failure Analysis; Exact sciences and technology; Friction; Friction drives; Fundamental areas of phenomenology (including applications); General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Motion; Motors; Nanotechnology - instrumentation; Nanotechnology - methods; Physics; Projection; Silicon; Sliders; Stress; Surface acoustic waves; Transducers; Transduction; acoustical devices for the generation and reproduction of sound; Acoustic wave device; Dynamic response; Force measurement; Vibration; Acoustic surface waves; Surface wave; Mechanical contact; Modeling; Punch; Ultrasonic motors; Rayleigh wave; Linear motor; Elastic half space; Sliding friction
• ISSN: 0885-3010; 1525-8955
• DOI: 10.1109/TUFFC.892

The mechanics of the friction drive of a surface acoustic wave motor were investigated by means of contact mechanics theory. As a means to control the contact condition, the motor's slider had projections on its frictional surface. Assuming the projection was a rigid circular punch and the slider body was an elastic half-space allowed application of contact mechanics formulae to the analyses of the friction drive. Because the projection contacted the Rayleigh wave vibration, the projection's responses were considered dynamic; thus, the dynamics were also analyzed in the same framework of contact mechanics formulae. Moreover, the analyses were applied to measurements of the projection's displacement to examine the detailed mechanics during the friction drive. We calculated the contact/frictional forces based on the measurement and indicated the necessity of further investigation of the surface acoustic wave motor's friction drive, because the usual friction law was unable to explain the measurement.