Leinvuo, Joni T.Wilson, Stephen A.Whatmore, Roger W.Cain, Markys G.2007-09-032007-09-032007-01-08Leinvuo JT, Wilson SA, Whatmore RW, Cain MG. (2007) A new flextensional piezoelectric ultrasonic motor - design, fabrication and characterisation. Sensors and Actuators A: Physical, Volume 133, Issue 1, January 2007, pp. 141-1510924-4247http://hdl.handle.net/1826/1853http://dx.doi.org/10.1016/j.sna.2006.04.010This paper presents the techniques used for the characterisation of a new type of standing-wave piezoelectric ultrasonic motor. The motor uses a metallic flextensional amplifier, or “cymbal”, to convert the radial mode vibrations of a piezoelectric ceramic disc into flexural oscillations, which are further converted to produce rotary actuation by means of an elastic fin friction drive. The motor operates on a single-phase electrical supply. A beryllium copper rotor design with three-fin configuration was adopted. The best stall torque, no load speed, transient time and efficiency for a 25 mm motor were 2 N mm, 680 rpm, 2 ms and 4.8%, respectively. The operational characteristics of the motor were evaluated by using two methods: one based on the pulley–brake principle and one on high-speed imaging. The results obtained from using these two techniques are contrasted and compared.826122 bytesapplication/pdfenUltrasonic motorFlextensional amplifierPulley-brakeHigh-speed imagingTorque measurementArticle