Rolling mass energy harvester for very low frequency of input vibrations

Abstract

This paper presents a novel design of a nonlinear kinetic energy harvester for very low excitation frequencies below 10 Hz. The design is based on a proof mass, rolling in a circular cavity in a Tusi couple configuration. This allows for an unconstrained displacement of the proof mass while maintaining the option of keeping the energy transduction element engaged during the whole cycle and thus reducing the required number of transduction elements. Both the presented model and the fabricated prototype of the device employ electromagnetic induction to harvest energy from low frequency and low magnitude vibrations that are typically associated with human movements. The prototype demonstrated an average power of 5.1 mW from a 1.3 g periodic acceleration waveform at 2.78 Hz. The highest simulated normalized power density reaches up to 230 μW/g 2 /cm 3 , but this depends heavily on the excitation conditions.

Analytical and Experimental Study on Gyroscopic Power Generator with Power Feedback

“…By inserting values of τ s and τ z to Eqs. (7) and (8), ω s and ω z after a short period are obtained. By repeating these procedures, all the parameters are obtained in the time domain.…”

“…In other wearable generators, the power output is 10 mW at most. (5)(6)(7) To increase inertial force at low frequencies, generators that use the gyroscopic effect have been studied. They increase the angular momentum of the vibrating mass by spinning it at a high angular velocity.…”

A Piezo-Electromagnetic Coupling Multi-Directional Vibration Energy Harvester Based on Frequency Up-Conversion Technique

“…However, this kind of energy harvester can only collect vibration energy in a certain direction [15,22], which has no obvious advantage for human motion or swing. Therefore, many researchers use rotating mass structure to harvest human motion energy [21,23,24]. For example, Smilek et al [23] present a novel design of a nonlinear kinetic energy harvester for very low excitation frequencies below 10 Hz.…”

“…Therefore, many researchers use rotating mass structure to harvest human motion energy [21,23,24]. For example, Smilek et al [23] present a novel design of a nonlinear kinetic energy harvester for very low excitation frequencies below 10 Hz. The design is based on a proof mass, rolling in a circular cavity in a Tusi couple configuration.…”

Ultra-low frequency energy harvesting using bi-stability and rotary-translational motion in a magnet-tethered oscillator

“…In addition to beam-based design, harvesters using sliding or rolling magnets provide new possibilities in low-frequency energy harvesting [29][30][31][32][33]. Rocha et al studied the dynamics of a non-ideal magnetic levitation system with a sliding magnet moving vertically in a tube [34].…”