Piezo-electrical sensors use the electrical material property of a piezo ceramic. A force change to the ceramic leads to an electrical charge between the bottom and the top side of the piezo.
For acceleration measurements the transducer has to convert the applied acceleration to a force which acts on the piezo ceramic. The generated charge can be converted by a charge amplifier, measured and calculated to an acceleration signal.
Due to the fact, that this sensor only measures a change of acceleration, it is not usable as a DC acceleration sensor. Only vibration and shock can be measured with this sensor concept.
The advantage of the piezoelectric sensors are the rubustness for high forces and the high resolution of small forces changes even with high initial loads. Commercial piezoelectric sensors are available with high measurement bandwidth (up to > 10 kHz). The sensor size is small and the costs are low priced.
- Comparison of acceleration sensors for a measurement problem
- Inductive sensors
- Capacitive sensors – MEMS