Applicability of ISO standard methods to vibration measurements at high frequencies and high accelerations

Abstract

New and revised laser methods and techniques developed by national metrology institutes and by leading manufacturers in the past two decades have been swiftly specified as standard methods in the ISO 16063 series of international document standards. The first international standard for the calibration of laser vibrometers, ISO 16063-41:2011, specifies the instrumentation and procedures for performing primary and secondary calibrations of rectilinear laser vibrometers in "typical" ranges of frequency (0,4 Hz to 50 kHz) and other conditions, with "typical attainable uncertainties" (0,25% to 5% for different specified conditions). This allows the specified standard methods to apply with refined techniques and procedures achieving even wider measurement ranges and smaller measurement uncertainties than that specified in the ISO standard. Recent theoretical and experimental investigations demonstrate the applicability of the standardized interferometric methods up to frequencies considerably higher than 50 kHz if measurable vibration amplitudes are generated. Sinusoidal vibration was generated by a piezoelectric actuator at frequencies between 63 kHz and 347 kHz and the displacement was measured by different interferometric standard methods applied simultaneously. Their results differed by less than 1% from each other. From the analysis of the results it is expected that frequencies up to 500 kHz are achievable.