Piezoelectric Impedance Method Using Multiple Piezoelectric Elements

Truss structure is widely used in civil engineering applications for its advantages of easy transportation, convenient assembly and uniform loading. However, it is difficult to achieve real-time health monitoring because of connection diversity and complexity of truss structures. As a novel structural health monitoring technique, electro-mechanical impedance method could monitor the health state of one structure by measuring the spectra of impedance or admittance of the piezoelectric elements, which are bonded on the surface of this structure. This approach has the advantages of nonparametric model analysis, easy sensor installation and high local sensitivity, especially in sensitive frequency range. The damage information, which is tested and recorded by using electromechanical impedance method, could convert into intuitive results through neural network because of its good ability for nonlinear mapping. In this paper, a three-layer assembly truss structure was chosen as experimental object, piezoelectric elements were bonded on structure joints to measure structural impedance spectra, the change of these structural impedance spectra was tested and recorded under high frequency excitations when different truss bars were loosed, and then, one back-propagation (BP) neural network was built and trained by this damage information, which were treated as input samples. These results show that the sensitivity of impedance method is not the same to different frequency range and trained neural network could quickly identify loosen truss bars.

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Damage Detection of Textile Composite Structures Using the Piezoelectric Impedance Method

American Society for Composites 2018 ◽

10.12783/asc33/26182 ◽

2018 ◽

Author(s):

SAZID AHMED ◽

PEI CAO ◽

DIANYUN ZHANG ◽

JIONG TANG

Keyword(s):

Damage Detection ◽

Composite Structures ◽

Impedance Method ◽

Textile Composite ◽

Piezoelectric Impedance

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Piezoelectric Electro-Mechanical Impedance (EMI) Based Structural Crack Monitoring

Applied Sciences ◽

10.3390/app10134648 ◽

2020 ◽

Vol 10 (13) ◽

pp. 4648 ◽

Cited By ~ 1

Author(s):

Tao Wang ◽

Bohai Tan ◽

Mingge Lu ◽

Zheng Zhang ◽

Guangtao Lu

Keyword(s):

Resonance Frequency ◽

Signal To Noise Ratio ◽

Mechanical Impedance ◽

Peak Frequency ◽

Crack Size ◽

Impedance Method ◽

Small Scale ◽

Element Simulation ◽

Piezoelectric Impedance ◽

Good Repeatability

To detect small cracks in plate like structures, the high frequency characteristics of local dynamics were studied with the piezoelectric electro-mechanical impedance (EMI) method, and damages were monitored by the changes of the EMI. The finite element simulation model of EMI was established, and numerical analysis was conducted. The simulation results indicated that the peak frequency of the piezoelectric admittance signal is a certain order resonance frequency of the structure, and the piezoelectric impedance method could effectively detect the dynamic characteristics of the structure. The piezoelectric admittance simulation and experimental study of aluminum beams with different crack sizes were performed. Simulation and experimental results revealed that the peak admittance frequency decreases with the increase of crack size, and the higher resonance frequency is more sensitive to the small-scale damage. The proposed method has good repeatability and strong signal-to-noise ratio to monitor the occurrence and development of small-scale crack damage, and it has an important application prospect.

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Numerical and Experimental Investigation of the Sensing Area of Piezoelectric Elements for Damage Detection with the E/M Impedance Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.413-414.253 ◽

2009 ◽

Vol 413-414 ◽

pp. 253-260 ◽

Cited By ~ 2

Author(s):

Ke Jia Xing ◽

Rolf T. Schulte ◽

Claus Peter Fritzen

Keyword(s):

Experimental Investigation ◽

Piezoelectric Element ◽

Spectral Element ◽

Impedance Method ◽

Element Mesh ◽

Sensor Position ◽

Piezoelectric Elements ◽

Simulation And Experiment ◽

High Frequency Excitation

During this decade, piezoelectric elements are explored and applied successfully in SHM, which has positioned them as an enabling technology for damage assessment. When permanently bonded to the structure, they provide the bi-directional energy conversion, which is used in impedance-based SHM. In this method, the variations of the structure’s impedance are monitored by piezoelectric elements. However, before experiments are performed, it is important to position correctly the piezoelectric elements on the structure. Therefore, the capability of piezoelectric actuators is explored under the aspect of sensor position. This work presents the investigation of sensing ability of surface-bonded piezoelectric element using numerical simulation and experiment. The results of numerical and experimental investigation are shown in this paper, which illuminates the model in the aluminium plate could be used to predict the state of it. In the experimental investigation, it also shows the factors which influence strongly the capability of sensor detection. Dealing with high frequency excitation, calculation requires a very dense finite element mesh, hence, the spectral element method (SEM) is chosen as model-based method, which is much more efficient than classical FEM. The structure, self-sensing elements as well as damage are modelled, from which the spectra of E/M impedance is computed. It gives the theoretical basis for the experiment design. The numerical results are verified and validated by experimental investigation. With such a numerical tool, the efficiency of the E/M impedance method can be clearly improved with respect to the determination of suitable piezoelectric element locations.

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The Study on Piezoelectric Impedance Technique Used in Loading Damage Identification

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.139-141.2612 ◽

2010 ◽

Vol 139-141 ◽

pp. 2612-2615 ◽

Cited By ~ 2

Author(s):

Jun Zhang ◽

Zi Jian Qin

Keyword(s):

Material Property ◽

Health Monitoring ◽

Damage Identification ◽

Damage Index ◽

Impedance Method ◽

Frequency Range ◽

Impedance Analyzer ◽

Testing Frequency ◽

Impedance Technique ◽

Piezoelectric Impedance

The superiority and feasibility of piezoelectric impedance method used in damage detecting was expounded, and the research status of the technical was summarized. Then, the rationale of the basic theory of the technique used in damage identification and health monitoring was analyzed here. The experiment of the damage change of loaded beam was researched. The experiment of the beam which was loaded by a material property, the value of the beam was got by an impedance analyzer, while the beam with different pull force. The research indicates that while the testing frequency range should elect as 300k-800k, with the increasing of loading force, the value of real part impedance is descending, the damage index of beam is increasing. PZT can sensitively catch the influence brought by stress varying

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A PZT-based electromechanical impedance method for monitoring the moisture content of wood

Sensor Review ◽

10.1108/sr-03-2021-0109 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Quan Zhai ◽

Jicheng Zhang ◽

Guofeng Du ◽

Yulong Rao ◽

Xiaoyu Liu

Keyword(s):

Moisture Content ◽

Mechanical Impedance ◽

Impedance Method ◽

Impedance Change ◽

Monitoring Method ◽

Content Type ◽

Electromechanical Impedance ◽

Wide Range ◽

Impedance Technique ◽

Piezoelectric Impedance

Purpose At present, piezoelectric impedance technology has been used in the study of wood damage monitoring. However, little effort has been made in the research on the application of piezoelectric impedance system to monitor the change of wood moisture content (MC). The monitoring method of wood MC is used by piezoelectric impedance technique in this study. Design/methodology/approach One piezoceramic transducer is bonded to the surface of wood specimens. The MC of the wood specimens increases gradually from 0% to 60% with 10% increments; the mechanical impedance of the wood specimen will change, and the change in the mechanical impedance of the structure is reflected by monitoring the change in the electrical impedance of lead zirconate titanate. Therefore, this paper investigates the relationship between wood MC change and piezoelectric impedance change to verify the feasibility of the piezoelectric impedance method for monitoring wood MC change. Findings The experiment verified that the real part of impedance of the wood increased with the increase of wood MC. Besides, the damage index root mean square deviation is introduced to quantify the damage degree of wood under different MC. At the same time, the feasibility and validity of this experiment were verified from the side by finite element simulation. Finally, MC monitoring by piezoelectric impedance technique is feasible. Originality/value To the best of the authors’ knowledge, this work is the first to apply piezoelectric ceramics to the monitoring of wood MC, which provides a theoretical basis for the follow-up study of a wide range of wood components and even wood structure MC changes.

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Modeling of Contact Patch in Dual-Chamber Pneumatic Tires

Tire Science and Technology ◽

10.2346/tire.18.460202 ◽

2018 ◽

Vol 46 (2) ◽

pp. 78-92 ◽

Cited By ~ 2

Author(s):

A. I. Kubba ◽

G. J. Hall ◽

S. Varghese ◽

O. A. Olatunbosun ◽

C. J. Anthony

Keyword(s):

Strain Sensors ◽

Surface Strain ◽

Wireless Data ◽

Data Logger ◽

Dual Chamber ◽

Piezoelectric Polymer ◽

Pure Rolling ◽

Piezoelectric Elements ◽

Strain Data ◽

Deformation Patterns

ABSTRACT This study presents an investigation of the inner tire surface strain measurement by using piezoelectric polymer transducers adhered on the inner liner of the tire, acting as strain sensors in both conventional and dual-chamber tires. The piezoelectric elements generate electrical charges when strain is applied. The inner liner tire strain can be found from the generated charge. A wireless data logger was employed to measure and transmit the measured signals from the piezoelectric elements to a PC to store and display the readout signals in real time. The strain data can be used as a monitoring system to recognize tire-loading conditions (e.g., traction, braking, and cornering) in smart tire technology. Finite element simulations, using ABAQUS, were employed to estimate tire deformation patterns in both conventional and dual-chamber tires for pure rolling and steady-state cornering conditions for different inflation pressures to simulate on-road and off-road riding tire performances and to compare with the experimental results obtained from both the piezoelectric transducers and tire test rig.

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