An energy harvesting system can comprise an actuator comprising a translationally displaceable surface, the translationally displaceable surface being configured to transition from a first position to a second position upon contact by a movable unit; a vertical rack in contact with the actuator, and configured to be translationally displaced in response to translational displacement of the actuator; a pinion configured to engage with the vertical rack and to rotate in response to translational displacement of the vertical rack; a main shaft coupled to the pinion and configured to rotate with rotation of the pinion; and a flywheel and a generator coupled to the main shaft, wherein rotation of the main shaft generates mechanical energy stored by the flywheel, and wherein the generator is configured to generate electrical energy from the mechanical energy stored by the flywheel.