Piezoelectric sensor

About: Piezoelectric sensor is a research topic. Over the lifetime, 7127 publications have been published within this topic receiving 115903 citations.

Health monitoring of a concrete structure using piezoceramic materials

Abstract: Health monitoring for reinforced concrete bridges and other large-scale civil infrastructure has received considerable attention in recent years. Traditional inspection methods (x-ray, C-scan etc.) are expensive and sometimes ineffective for large-scale structures. Piezoceramic transducers have emerged as new tools to health monitoring of large size structures due to the advantages of active sensing, low cost, quick response, availability in different shapes, and simplicity for implementation. In this research, piezoceramic transducers in the form of patches are used to detect internal cracks of a 6.1-meter long reinforced concrete bridge bent-cap. Piezoceramic patches are embedded in the concrete structure at pre-determined spatial locations prior to casting. This research can be considered as a continuation of an early work, where four piezoceramic patches were embedded in planar locations near one end of the bent-cap. This research involves ten piezoceramic patches embedded at spatial locations in four different cross-sections. To induce cracks in the bent-cap, the structure is subjected to loads from four hydraulic actuators with capacities of 80-ton and 100-ton. In addition to the piezoceramic sensors, strain gages, LVDTs, and microscopes are used in the experiment. During the experiment, one embedded piezoceramic patch is used as an actuator to generate sweep sinusoidal waves, and the other piezoceramic patches are used as sensors to detect the propagating waves. With the increase of number of and severity of cracks, the magnitude of the sensor output decreases. Wavelet packet analysis is used to analyze the recorded sensor signals. A damage index is formed on the basis of the wavelet packet analysis. The experimental results show that the proposed methods using piezoceramic transducers along with the damage index based on wavelet packet analysis is effective in identifying the existence and severity of cracks inside the concrete structure. The experimental results also show that the proposed method has the ability to predict the failure of concrete as verified by results from conventional microscopes (MS) and LVDTs.

Composite piezoelectric transformer

Abstract: A multi-layer piezoelectric transformer (1) is provided that is capable of achieving high mechanical momentum and, therefore, is capable of high energy transmission. The piezoelectric tranformer (1) has a plurality of layers (43, 44, 53, 54, 63, 64) arranged as a composite structure. The outermost portions (31, 33) of the piezoelectric transformer (1) comprise the input portions, which are bonded to the central output portion (32) of the piezoelectric transformer (1). The construction and anisotropic nature of the piezoelectric transformer (1) allows it to be driven at the longitudinal resonant frequency of the piezoelectric transformer (1) corresponding to its overall thickness, which increases the achievable gain and power density of the piezoelectric transformer (1).

Review on high temperature piezoelectric ceramics and actuators based on BiScO3–PbTiO3 solid solutions

Abstract: In recent years, industries in the fields of petrochemical, automotive, and aerospace have expressed their interest in utilizing piezoelectric actuators for high-temperature (HT) operations at the temperature above 150°C. HT piezoelectric ceramics (1-x) BiScO3–xPbTiO3 (BS–PT) are considered as one of the most competitive piezoelectric actuation materials used in the harsh environment because of its high Curie temperature (TC = 450°C) as well as high piezoelectric coefficient (d33 = 460 pC/N ) in the MPB composition. This paper summarized the recent progress in HT piezoelectric ceramics and actuators based on BS–PT solid solutions. The properties of BS–PT piezoelectric ceramics and actuators, including driving mechanisms, actuation performances and their applications in HT environment were also discussed.

Experimental investigation of active vibration control using neural networks and piezoelectric actuators

Abstract: The use of neural networks for identification and control of smart structures is investigated experimentally. Piezoelectric actuators are employed to suppress the vibrations of a cantilevered plate subject to impulse, sine wave and band-limited white noise disturbances. The neural networks used are multilayer perceptrons trained with error backpropagation. Validation studies show that the identifier predicts the system dynamics accurately. The controller is trained adaptively with the help of the neural identifier. Experimental results demonstrate excellent closed-loop performance and robustness of the neurocontroller.