In order to harvest vibrational energy, there has to be a generator that can convert the vibration frequency into electricity.

There are three main types of generators: piezoelectric, electromagnetic, and electrostatic.

Currently developing applications of vibrational energy harvesting include using vibrations generated during aircraft flight to supply airplane electronics, and using vibrations of machines in factories to power sensors.

There is also the potential for future use in self-powered medical implants which would harvest the vibrational energy of a beating human heart. 

pathways:

Ek=12kx2

ReVibe Energy / Electromagnetic vs. piezoelectric vibration energy harvesting: What is the difference?

16.07.2020 / AltEnergyMag / Producing Energy from Vibrations

2004 / Science Direct / Vibrational Energy