Dynamic calibration method for a piezoelectric force and moment transducer

The recent availability of compact piezoelectric transducers to measure both a normal force and two moments may fulfill the previously overlooked need for measuring not only forces, but also moments to achieve a complete understanding of a mechanical structure's behavior. In order to obtain meaningful measurements some reliable calibration practices must be developed. Experience shows that the transducer's dynamic characteristics are dependent upon the test set-up. Two different test items and excitation methods were followed: 1) a steel bar excited by pseudo-random vibration, and, 2) an aluminum plate subject to impact excitation. The calibration was performed by measuring the input-output transfer functions over a 0 to 800 Hz. There are significant cross-axis sensitivities which in some cases may give wrong measurement information.