Multi-dimensional constrained energy optimization of a piezoelectric harvester for E-gadgets

Area of Science:

• Mechanical Engineering
• Materials Science
• Energy Harvesting

Background:

• Electronic gadgets (e-gadgets) consume significant power, leading to frequent recharging.
• Existing energy harvesting solutions often lack efficiency or are not integrated seamlessly with device motion.
• Scavenging ambient kinetic energy from device movement presents a sustainable power source.

Purpose of the Study:

• To design and optimize an energy harvesting device that utilizes the rocking motion of e-gadgets.
• To enhance energy scavenging efficiency through a frequency up-conversion plucking mechanism.
• To maximize harvester performance using a multidimensional surrogate optimization algorithm within operational constraints.

Main Methods:

• A novel plucking mechanism inspired by frequency up-conversion was employed to excite piezoelectric beams.
• A multidimensional surrogate optimization algorithm was used to optimize the harvester's geometrical features.
• A numerical model of the energy harvester was developed and validated against experimental data.

Main Results:

• The optimized 10.2-inch energy harvesting device generated 55 mJ in a half-period at a 45° inclination.
• The device achieved an output power of 0.3 W.
• The energy harvester demonstrated the potential to extend the battery life of a similar-sized e-gadget by 10%.

Conclusions:

• The developed energy harvesting device effectively scavenges energy from the rocking motion of e-gadgets.
• The frequency up-conversion plucking mechanism significantly enhances excitation and energy generation.
• The optimized harvester offers a practical solution for extending the battery life of portable electronic devices.