Grove - Piezo Vibration Sensor is suitable for measurements of flexibility, vibration, impact and touch. The module is based on PZT film sensor LDT0-028. When the sensor moves back and forth, a certain voltage will be created by the voltage comparator inside of it.
Therefore, outputs high & low levels. In spite of the fact that it has a high receptivity for strong impacts, a wide dynamic range (0.001Hz~1000MHz) also guarantees excellent measuring performance. Finally, you can adjust its sensitivity by adjusting the potentiometer with a screw.
The Grove - Vibration Sensor (SW-420) is a high sensitivity non-directional vibration sensor. When the module is stable, the circuit is turned on and the output is high.