Breaking the Sensitivity Bandwidth Trade-Off with a Multi-Pzt-Cantilever-Based Mems Acoustic Emission Sensor for Structural Health Monitoring of Infrastructure

This paper presents a multi-type MEMS-based piezoelectric acoustic emission sensor (AE) that addresses the conventional trade-off between sensitivity and bandwidth. Seventeen Lead zirconate titanate (PZT) cantilevers, each tuned to a distinct resonance frequency ranging from 20 to 100 kHz in 5 kHz increments, are electrically connected in parallel. This configuration enhances individual sensitivity through resonance and structural optimization, while enabling scalable bandwidth expansion by adding cantilevers with different frequencies. Steel ball hammer impact tests on concrete specimen confirm that the multi-type sensor's AE detection bandwidth and sensitivity are comparable to those of a commercial bulk sensor, demonstrating its potential for infrastructure structural health monitoring.