ISO 16063-11:1999

Overview

ISO 16063-11:1999 - "Methods for the calibration of vibration and shock transducers - Part 11: Primary vibration calibration by laser interferometry" defines primary calibration procedures for rectilinear accelerometers using steady-state sinusoidal vibration and laser interferometry. The standard covers magnitude and phase (complex sensitivity) determination over a frequency range 1 Hz to 10 kHz and a dynamic acceleration range nominally 0.1 m/s² to 1000 m/s² (frequency-dependent), with specified measurement uncertainties.

Key topics and technical requirements

• Scope: Primary vibration calibration of accelerometers (with or without amplifier) to obtain sensitivity magnitude and phase lag by laser interferometry.
• Measurement uncertainty:
  • Magnitude: ±0.5% (reference conditions), up to ±1% outside reference conditions.
  • Phase: ±0.5° (reference conditions), up to ±1° outside reference conditions.
  • Recommended reference frequencies: 8, 16, 40, 80, 160 Hz (and corresponding radian frequencies) and reference accelerations from 1 to 100 m/s².
• Three prescribed methods:
  • Method 1 (fringe-counting): Sensitivity magnitude, applicable 1 Hz to 800 Hz (and under special conditions above 800 Hz).
  • Method 2 (minimum-point): Sensitivity magnitude using fixed displacement amplitudes, applicable 800 Hz to 10 kHz.
  • Method 3 (sine-approximation): Magnitude and phase, applicable 1 Hz to 10 kHz; enables lower-frequency or smaller-amplitude calibrations when paired with suitable vibration generators.
• Key instrumentation requirements:
  • Helium–neon laser (wavelength 0.63281 μm under standard laboratory conditions) or equivalent single‑frequency laser.
  • Michelson interferometer (modified with quadrature outputs for Method 3).
  • Stable frequency generator, power amplifier/vibrator, heavy seismic block(s), counting or spectrum-analysis instrumentation, and low-distortion vibration source.
  • Performance specs for harmonic distortion, transverse motion limits, bandwidth, signal-to-noise and stability are defined to achieve stated uncertainties.

Applications and users

• Used by national metrology institutes, accredited calibration laboratories, accelerometer manufacturers, and industrial test laboratories to establish traceable, primary-level calibrations of vibration sensors.
• Practical applications include instrument traceability for structural testing, aerospace and automotive vibration testing, modal analysis, condition monitoring, and any measurement requiring high-accuracy accelerometer sensitivity and phase information.
• Method selection depends on frequency/amplitude requirements, desired phase information, and available vibration generation hardware.

Related standards

• ISO 16063 series (general calibration concepts are given in ISO 16063-1).
• Other parts include reciprocity and shock calibration methods (e.g., ISO 16063-12, ISO 16063-13) which complement laser interferometry procedures.

Keywords: ISO 16063-11, vibration calibration, laser interferometry, accelerometer calibration, primary calibration, Michelson interferometer, fringe-counting, minimum-point method, sine-approximation, measurement uncertainty.