SkyHarvester: A Mechanically Amplified Energy Harvesting Module with Adjustable Resonant Frequency

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Project Team
Patrick Burke
Arnur Maratov
Siem Mihreteab
Frederick Miller
Anjali Vu

Project Sponsor(s)
Dr. Farid Hassani, Aerosens

Instructor(s)
Dr. Amir Aslani, ECE, GW Engineering
Dr. Steven Shooter, MAE, GW Engineering

The objective of this project is to develop an energy harvesting module (EHM) for use in the airline industry to reduce the need to replace single-use coin cell batteries that power preflight internet of things (IoT) sensors. The EHM shall include a mechanical amplifier to increase the overall amount of energy being harvested, as well as frequency tuning capabilities to ensure compatibility with various aircraft models. This combination will allow the EHM to harvest energy at maximum efficiency in multiple aircrafts that have unique dominant vibration frequencies. By increasing the amount of power harvested, the project will increase the life of blue-tooth low energy (BLE) sensor batteries dramatically, reducing environmentally harmful consumables and cutting back on labor costs.

Who experiences this problem?

Our biggest client base for SYFT Schedule is college students. As students leave their hometowns and enter college, they're most likely experiencing total independence for the first time in their lives. Balancing their classes, activities, and study sessions while still finding time to rest can be difficult, so SYFT Schedule aims to take some of that burden away, so they can focus on what matters most to them.

Why is this important?

An optimized energy harvesting module would produce a large amount of power over a wide frequency bandwidth, allowing the module to be applied to various aircraft models and to properly power the IoT sensor using aircraft vibrations. Additionally, an energy harvesting solution for sensors would eliminate the need for coin-cell battery replacement, reducing long term costs and waste.

What is the coolest thing about your project?

This project utilizes repelling magnets to create a bistable system, leveraging nonlinearity specifically under low frequency and broad-band input excitations. With the repelling magnets and a variable distance, the system is able to significantly increase the deflection of the piezoelectric cantilever, increasing the voltage output. Additionally, the repelling magnets in the bistable configuration (2 stable states) allow for efficient energy harvesting over a range of frequencies, not just the input system's resonant frequency. This is due to the nonlinear dynamics that occur during inter-well motion between stable states of the harvester system. As a result of inter-well motion, the energy harvesting of the bistable structure is dependent on the amplitude of the input vibrations, not the frequency. This leads to a broadband harvesting system that is beneficial for aerospace applications.

What sustainable design considerations drove your solution?

The energy harvesting module makes use of ambient aircraft vibrations, eliminating the need for single use coin-cell batteries and decreasing waste. This assists in the push towards cleaner, greener aviation.

What were some technical challenges?

The nonlinear dynamics of the repelling magnets were difficult to model, as their behavior changes drastically with separation distance. Modeling the nonlinear system was a difficult task, however the team was able to obtain parameters for baseline testing.