Vibration Energy Harvesting

• Analysis and experimental validation of multiple mistuned pendulum harvesters: both independent and coupled.
• Optimization of coupling between adjacent mistuned harvesters to enhance power harvested.
• Investigation of benefits of coupling of mistuned harvesters for broadband harvesting.
• Investigation of effect of magnetic coupling along with mechanical coupling on harvester performance.

The bandwidth of vibration energy harvesters could be increased by engineering multiple stable states. In cantilever based energy harvesters, multiple stable states could be introduced through buckling. For instance, an inverted cantilever beam can be buckled by adding a tip mass that exceeds the critical buckling load. The buckled beam would have two stable static equilibrium positions and is bistable.

To get more than two stable states, the concept of magneto-elastic bucking is employed.

Such multi-stable systems vibrate in a non-resonant manner between the multiple stable states, producing a broadband response. Attaching piezoelectric patches to the beam would help to harvest electrical energy over a moderate range of frequencies.

Further, multi-stable systems exhibit a rich dynamical behavior. These systems are nonlinear and undergo chaotic oscillations in the presence of a harmonic excitation of suitable amplitude and frequency. To understand more about the behavior of such systems, click here.

(Contents will be updated soon)

Dynamic vibration absorbers are used for vibration damping and isolation in structures. Addition of piezoelectric patches provides additional damping to the system and the patches also convert a part of the vibration energy absorbed into electrical energy.