Conference Paper

Determination of surface mechanical properties using a hertzian contact and ultrasound sensor

Robot. & Adv. Manuf. Program, CINVESTAV, Coahuila, Mexico
DOI: 10.1109/ULTSYM.2010.5935526 Conference: Ultrasonics Symposium (IUS), 2010 IEEE
Source: IEEE Xplore

ABSTRACT

Nondestructive monitoring of contact properties for biological and engineering materials is important in several engineering areas. Also, in robotics, manipulation of fragile objects requires precise determination of instantaneous contact area and forces with minimum intrusion. In this paper, a contact probe based on hertzian contact and ultrasonic energy transmission for characterization of surface properties is proposed. The probe is built from a solid semi-spherical head which is sonified from the top by an ultrasonic transducer with a center frequency of 1 MHz. Force range was 0-23N and displacements as small as 0.05 millimeters were reached with a proposed automatic control system. A quasi-static spring model to describe the interfacial properties at contact is studied. The results indicate that due to its high sensitivity, the probe could be used for measurements of surface mechanical response.

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    • "However, by using a probe with smooth surface in the submicron range, low frequencies, and considering that the test probe has much higher material yielding than the probe, the amount of reflected energy could be closely correlated to the nominal contact area [32]. An example of the time domain signal response observed from the Plexiglass semi-spherical probe/air interface is shown in Fig. 2. Time and frequency domain analysis of echo-pulse signals were used for the monitoring of signal amplitude variations [33] [34]. Fig. 1. "
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