SYDE Graduate Seminar - Additively Manufactured Cellular Piezoelectric Energy Harvesters

Presenter

Nabil Omar Alaid, PhD candidate in Systems Design Engineering

Abstract

This thesis investigates the design, fabrication, and characterization of low-frequency piezoelectric vibration energy harvesters that combine additive manufacturing with screen-printed thick-film piezoelectrics. The central objective is to demonstrate the compatibility of these two fabrication techniques and to quantify the influence of a cellular architecture on electromechanical performance. Metallic substrates are produced by Selective Laser Melting (SLM) from 17-4 PH stainless steel powder, onto which a thick-film (50 to 100 µm) Pb(Zr,Ti)O₃ (PZT) layer is screen-printed between two gold electrodes.

Seven devices are fabricated and tested, comprising three cellular plates, three cellular beams, and one solid beam, allowing a direct comparison between cellular and solid architectures. Each device is subjected to both mechanical and electrical characterization to determine its resonant behavior, frequency response, and power output under optimized load resistance. The cellular beam has an overall length of 80 mm and a width of 15 mm, incorporating an approximately 70 µm thick PZT layer. The reduced effective stiffness introduced by the cellular geometry lowers the resonant frequency and enables operation in the low-frequency range relevant to ambient vibration sources. The cellular plate, measuring 70 mm in length and 50 mm in width with a 20 mm clamped region, delivers the highest output, producing on the order of 300 µW at a resonant frequency of 28 Hz with a 15 g tip mass after load resistance optimization. The cellular beam yields a maximum output power of 24 µW at a resonant frequency of approximately 20 Hz with a 5 g tip mass.

A finite element model is developed to predict the electromechanical response of the harvesters. Comparison between numerical and experimental results shows good agreement, with a maximum error of 15% in predicted output power. Benchmarking against reported devices situates the present harvesters within the current state of the art for low-frequency operation. Overall, the results demonstrate the potential of additively manufactured cellular architectures combined with screen-printed thick-film PZT for efficient low-frequency vibration energy harvesting and validate the proposed modeling approach.

Join in-person in E5-6008.

This seminar counts towards the graduate student seminar attendance milestone!