Evaluating Energy Generation Capacity of PVDF Sensors: Effects of Sensor Geometry and Loading

Abstract

This paper focuses on the energy generating capacity of polyvinylidene difluoride (PVDF) piezoelectric material through a number of prototype sensors with different geometric and loading characteristics. The effect of sensor configuration, surface area, dielectric thickness, aspect ratio, loading frequency and strain on electrical power output was investigated systematically. Results showed that parallel bimorph sensor was found to be the best energy harvester, with measured capacitance being reasonably acceptable. Power output increased with the increase of sensor’s surface area, loading frequency, and mechanical strain, but decreased with the increase of the sensor thickness. For all scenarios, sensors under flicking loading exhibited higher power output than that under bending. A widely used energy harvesting circuit had been utilized successfully to convert the AC signal to DC, but at the sacrifice of some losses in power output. This study provided a useful insight and experimental validation into the optimization process for an energy harvester based on human movement for future development.

A Class of Rigid–Flexible Coupling Crystalline Crosslinked Polymers as Vapomechanical Actuators

“…Mechanically responsive actuators are capable of directly converting inexpensive and readily available external stimuli (e.g., chemical vapor, [1][2][3][4] light [5][6][7][8][9] ) into mechanical work, accompanied by reversible deformation of materials (e.g., expansion, contraction, bending, twisting, rolling). They have shown broad application prospects in many high-tech fields such as robots, [10,11] sensors, [12] aerospace, [13] energy storage, [14] biomedical engineering, [15] and so on. Currently, mechanically responsive actuators are mostly composed of polymeric materials such as organic polymers, [16] hydrogels, [17,18] and liquid-crystal elastomers [19] because of their high mechanical properties and processability that benefit the fabrication of macroscale devices such as artificial muscles and soft actuators.…”

Multiferroic Cantilevers Containing a Magnetoactive Elastomer: Magnetoelectric Response to Low-Frequency Magnetic Fields of Triangular and Sinusoidal Waveform

“…PEP was a flexible component comprising a thin (thickness µm) PE PVDF polymer film with screen-printed silver ink electrodes, laminated to a 0.125 mm polyester substrate, and fitted with two crimped contacts. Because the PE film was displaced from the mechanical neutral axis, bending created a very high strain within the PVDF layer and high voltages were generated [ 31 , 32 ]. The fabrication procedure of heterostructures was described in detail in [ 24 ].…”

A Stretchable and Conformable Sensor Fabricated by PVDF Film for human dynamic monitoring

“…For example, a stretchable, conformal hydration sensor can be used to monitor the skin hydration by using of stretchable AgNW/PDMS electrode [4], and a biocompatible, conformal sensor can be used as strain and pressure sensor for heart rate and body movement detection [5]. The flexible and conformal sensors are usually made of elastomer composites with polymer materials and nano-particles like polyacrylamide/calcium-alginate [2], Poly (vinylidene fluoride) [6,7], or polyurethane -poly (3, 4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT: PSS) [8] . Therefore, a growing number of flexible and conformal sensors had a strong elastic structure to enhance sensitivity in human movement detection, which can efficiently detect various movements relevant to human activities [9][10][11][12][13][14].…”