This standard measuring device has been developed to simultaneously generate and precisely measure motion quantities in up to three orthogonal directions (X, Y, Z). It can be used for multi-component calibrations of transducers, measuring chains and measuring instruments for motion quantities. Multi-component transducers (e. g. tri-axial accelerometers) can be calibrated applying user-defined excitation. As regards the calibration of single-component transducers, it has become possible to simulate disturbing motion components in unwanted degrees of freedom, in addition to the measurand. The translational motion quantities (acceleration velocity and displacement) can be generated and accurately measured in all 3 components with defined time dependencies which can be arbitrarily chosen within wide ranges (sinusoidal, shock-shaped, noise and special, user-defined time histories).
Multi-component acceleration standard measuring device
The translational tri-axial exciter has been designed for a frequency range from 1 Hz to 1 kHz and accelerations of up to 100 m/s2. The high loading masses of up to 100 kg for the tri-axial exciter allow, in addition to transducer calibrations, also the dynamic behaviour of mechanical structures at multi-component excitation to be investigated.
The intensity parameters of motion quantities (e. g. amplitude of a sinusoidal acceleration) and the sensitivity of precise transducers can be measured with measurement uncertainties between 0,5 % and 1 %. Complete acquisition and measurement of the time histories of the motion quantities are carried out by the laser interferometers associated with the standard measuring device (absolute measurement and primary calibration). A set of accelerometer standards offers yet another independent measurement capability (comparison method).
The standard measuring device consists of:
- Multi-component acceleration exciter
- Air-suspended vibration isolation block of 60 t for multi-component acceleration exciter
- Combined passive-active vibration isolation systems for associated interferometers (position control better than 0,5 µm; active vibration isolation from to 1 Hz to 200 Hz)
- A set of laser interferometers for multi-component measurement
- System for measuring signal acquisition and processing.