DFRobot Gravity Flexible Piezo Film Vibration Sensor

This electronic vibration sensor from DFRobot uses a Piezo element to measure vibrations/shocks. A Piezo element generates electricity when subjected to mechanical stress (vibrations) which means that there is no need to provide a power supply to the sensor. In addition to vibrations, the sensor can also measure when pressure is exerted on the piezo element. The sensor can easily be read analogue or digitally by, for example, an Arduino or Raspberry Pi.

See the following page for more information: Wiki