A non-resonant rotational electromagnetic energy harvester for low-frequency and irregular human motion

Abstract

There is an abundance of low-frequency and irregular human motion energy that can be harvested. In this work, a non-resonant rotational electromagnetic energy harvester (REH) for scavenging low-frequency (<10 Hz) and irregular human motion is presented. The energy harvester simply introduces a cylindrical stator and a disk-shaped rotor forming a movement of a higher pair. Without any complicated transmission mechanism, the rotor can easily rotate around the stator by magnetic attractive force. Driven by a broadband frequency vibration, the magnetic rotor is coupled with surrounding wound coils to operate electromagnetic energy harvesting. Theoretical and experimental investigations of the REH are studied, and numerical simulations show good agreement with the experimental results. The treadmill tests at various motion speeds are performed to demonstrate the advantage of the REH in harvesting energy from irregular human motion. At a driving frequency of 8 Hz, the electromagnetic coils can provide the maximum power of 10.4 mW at a load resistance of 100 Ω. The REH exhibits outstanding output performance and has potential applications for powering intelligent wearable or portable electronic devices.

An epidermal sEMG tattoo-like patch as a new human–machine interface for patients with loss of voice

“…Owing to the recent advances and the rapid development in soft materials and micro-electromechanical system (MEMS) fabrication, the emerging field of wearable flexible electronic devices offers a technological solution to measure the sEMG of the face, jaw, neck, etc. [11][12][13][14][15][16][17][18][19][20][21][22][23] . One of the major trends is to apply textiles made of functional yearns and coatings or to use flexible materials to fabricate devices for detecting physiological signals [24][25][26] , conducting drug delivery 27 , and realizing intuitive humanmachine interfaces [28][29][30][31] .…”

Hybridizing linear and nonlinear couplings for constructing two‐degree‐of‐freedom electromagnetic energy harvesters

“…14,15 Among these different electricity-generation technologies, the electromagnetic generator has been utilized for almost 200 years, but it still serves as a dominant way to convert other forms of energy into electricity to power modern societies owing to its superior duration. 9,18,19 Since the swing motion of the eccentric rotor generally leads to a slow change rate of the magnetic flux through the coil, the power provided by the first category of EMEHs is low. 17 Efforts to solve this issue have brought about several electromagnetic energy harvesters (EMEHs).…”

“…Similar to the conventional electromagnetic generators, the first category of EMEHs consists of a freestanding eccentric rotor and a fixed stator, but its operation depends on the swing motion of the eccentric rotor instead of the continuous rotation. 9,18,19 Since the swing motion of the eccentric rotor generally leads to a slow change rate of the magnetic flux through the coil, the power provided by the first category of EMEHs is low. In the second category, a set of pick-up coil is attached at the tip of a cantilever beam and a magnet is fixed to the frame, or vice versa.…”

A Direction Self-Tuning Two-Dimensional Piezoelectric Vibration Energy Harvester

“…So, a new type of energy harvester based on vibration energy collection has been widely studied. Vibration energy harvesting is mainly based on electromagnetic [2][3][4][5][6], electrostatic [7,8], triboelectric [9,10], and piezoelectric [11][12][13] conversion mechanisms. Among them, the piezoelectric vibration energy harvester (PVEH) has been widely studied due to its simple structure, high energy density, excellent voltage output, and easy integration with other devices.…”