Acoustic Energy Harvesting Using Linear Piezo Motors: Modeling, Validation, and Performance Analysis

Abstract

Ambient acoustic noise offers a vast, untapped potential for powering low-energy electronics, yet effective harvesting remains a technical challenge. This research explores a novel application of Piezo Linear Motors operating in reverse mode to convert environmental sound waves into electricity via the inverse piezoelectric effect. While the absolute power conversion efficiency (0.42%) aligns with existing literature, this work introduces a significant structural novelty: leveraging the broadband frequency response of Linear Piezo Motors to overcome the narrow bandwidth limitations of traditional cantilever designs. The primary objective is to develop a high-fidelity, real-time Digital Twin simulation using MATLAB/Simulink to evaluate the motor’s energy conversion efficiency under stochastic audio conditions, circumventing the unrealistic use of deterministic sine waves. The methodology integrates a live microphone input with a digital signal processing chain that employs band-pass filtering to isolate human speech frequencies (500–3000 Hz), followed by full-wave rectification and an integration algorithm to model realistic battery charging and leakage dynamics. Simulation and experimental results demonstrate that the linear motor structure effectively responds to dynamic acoustic pressure, generating a cumulative DC voltage sufficient to activate a thresholddependent load. This study contributes a cost-effective virtual prototyping framework, validating the feasibility of repurposing linear actuators as sustainable, wideband energy harvesters for self-powered IoT applications.