This basic vibration sensor hosts a piezo element & is used for flex, touch, vibration and shock measurements. A small AC and large voltage (up to +/-90V) is created when the piezo film moves back and forth. A simple resistor should get the voltage down to ADC levels. Can also be used for impact sensing or a flexible switch.
The piezoelectric transducer is displaced from the neutral axis during vibration, it creates strain on piezo element which generates voltage.
Operating voltage 12v DC
Output is signal pulse whose amplitude is proportional to vibration.
Frequecy Range 0.5Hz to 20Hz.