Wireless impedance sensor nodes for functions of structural damage identification and sensor self-diagnosis

Abstract

Economic and reliable online health monitoring strategies are very essential for safe operation of civil, mechanical and aerospace structures. This study presents online structural health monitoring (SHM) techniques using wireless impedance sensor nodes equipped with both functions of structural damage identification and sensor self-diagnosis. The wireless impedance sensor node incorporating a miniaturized impedance measuring chip, a microcontroller and radio-frequency (RF) telemetry is equipped with the capabilities for temperature sensing, multiplexing of several sensors, and local data analysis. The feasibility of the sensor node for structural damage identification is firstly investigated through a series of experimental studies inspecting loosened bolt damage and cut damage cases. Additionally, a temperature effects-free sensor self-diagnosis algorithm is embedded into the sensor node and its feasibility is examined from the experiments monitoring the integrity of each piezoelectric sensor on a wireless sensor network.

Piezoelectric Transducers Applied in Structural Health Monitoring: Data Acquisition and Virtual Instrumentation for Electromechanical Impedance Technique

“…This chip has been used in SHM to develop compact and low-cost measurement systems. These new systems support wireless communication and several sensors through analog multiplexer, and can process data locally (Min et al, 2010;Park et al, 2009). …”

Adverse event detection (AED) system for continuously monitoring and evaluating structural health status

“…The chip includes a DAC to generate an excitation signal up to 100 kHz, a 12-bit ADC, and supports on-chip FFT operation. Park et al integrated this chip with a microcontroller ATMega128 and an XBee wireless transceiver [10]- [12]. Researchers from Los Alamos National Lab have worked on a series of wireless SHM sensor systems embedded with Analog Device's impedance analyzer chips AD5933 for years and developed the third generation of the sensor system called Wireless Impedance Device (WID-3) in 2009 [13]- [15].…”

Smart sensing, monitoring, and damage detection for civil infrastructures

“…With the recent advances of signal processing techniques and the improvement of hardware including MEMS (MicroElectroMechanical Systems) technology and wireless data transmission, piezoelectric sensors become more attractive in on-line SHM as well as non-destructive testing. Some of the related researches and application activities are as follows: • Development of a piezoelectric oscillator sensor to detect damages on civil infrastructures • Impedance-based damage detection on civil structures (Park et al, 2006a) • Reference-free crack detection using piezoelectric sensors (Sohn, 2003;Kim and Sohn, 2006) • Piezoelectric sensor self-diagnosis using impedances (Park et al, 2006) • Smart dual PZT transducers for damage detection (Sohn et al, 2009) • On-line piezoelectric sensors-based SHM using wireless sensor nodes (Overly et al, 2007;Park et al, 2009;Zhou et al, 2010) • Various field applications using piezoelectric sensors-based sensing system Min et al, 2010) …”