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This paper seeks to study the feasibility of a stator vibration damping using piezoelectric (PZT) actuators applied to switched reluctance motors (SRM).

A single‐phase structure without moving rotor, but with the same shape as an SRM stator, is introduced to simplify the study and the experimental measurements. Both analytical and finite element methods are used to detail the chosen location and design of the PZT actuators for this structure.

Experimental results show that PZT actuators with a low voltage allow the decrease of the vibration level due to the electromagnetic forces.

To decrease the vibration level of the SRM stator in the real use of the machine, a closed loop system is necessary. Future works consist of the design of a closed loop numerical controller using an acceleration sensor as strain information.

The proposed damping method gives a new solution for the SRM noise problem that can be useful for people working on noise reduction on this machine.

So far vibration damping of SRM stator was obtained using a command or a geometry “acoustically” optimised, or active vibration with an auxiliary coil. The solution presented here applies PZT vibration damping to the stator with a thickness more important than the one of classical plates used for PZT damping applications.

To find properties of screen printed PZT (PbZr_0.53Ti_0.47O₃ with 6 per cent of PbO and 2 per cent of Pb₅Ge₃O₁₁) thick films layers on LTCC substrate.

The influence of PZT firing time and electrode materials on electrical characteristics and microstructure were examined. A scanning electron microscope (SEM) equipped with an energy‐dispersive X‐ray (EDS) analyser was used for the microstructural and compositional analysis.

Microstructural and compositional analyses have shown the diffusion of SiO₂ from LTCC into PZT layers and the diffusion of PbO in the opposite direction. SiO₂ presumably forms low permitivity lead based silicates in PZT layer. The new phase deteriorates the piezoelectric properties. The amount of diffused materials was dependent upon the electrode material and increased with increasing firing time. Better properties, i.e. higher remanent polarisation and dielectric constant were achieved for samples with PdAg electrodes and shorter firing time.

New information on electrical and microstructural properties of thick film PZT made on LTCC substrate.

The purpose of this paper is to provide an effective and simple technique for structural parameter identification, particularly to identify multiple cracks in a structure using simultaneous measurement of acceleration responses and voltage signals from PZT patches which is a multidisciplinary approach. A hybrid element constituted of one-dimensional beam element and a PZT sensor is used with reduced material properties which is very convenient for beams and is a novel application for inverse problems.

Multi-objective formulation is used whereby structural parameters are identified by minimizing the deviation between the predicted and measured values from the PZT patch and acceleration responses, when subjected to excitation. In the proposed method, a patch is attached to either end of the fixed beam. Using particle swarm optimization algorithm, normalized fitness functions are defined for both voltage and acceleration components with weighted aggregation multi-objective optimization technique. The signals are polluted with 5 percent Gaussian noise to simulate experimental noise. The effects of various weighting factors for the combined objective function are studied. The scheme is also experimentally validated by identification of cracks in a fixed-fixed beam.

The numerical and experimental results shows that significant improvement in accuracy of damage detection is achieved by the combined multidisciplinary method, when compared with only voltage or only acceleration-matching method as well as with other methods.

The proposed multidisciplinary crack identification approach, which is based on one-dimensional PZT patch model as well as conventional acceleration method, is not reported in the literature.

Purpose is to design the energy harvesters and to know the limit of the application of load on the PZT material. Fatigue failures of the designed products is merely bothering the modern engineers and scientists for the research communities of all fields. Especially in the field of Micro Electromechanical Systems (MEMS), durability of low power systems is very important under the climates of both at high temperature and low temperature zones. And also continuous electrical power requirement is important for the MEMS and wireless sensor networks. Electricity is the greatest crisis in the world on one side and on the other side, durability of smart devices such as mobile phones, laptops, compact devices, computer spare parts are unrecyclicable batteries for reducing the rate of pollution in the environment.

By considering these problems, authors have taken up a research in finding the first fatigue characteristics, which are fatigue failure and durability of ferroelectric material as lead zirconate titanate, and then designed the scavenging device by using harmonically excited vibrations for getting optimum power output which is about 15.6 mW.

Under the resonance operated condition at the frequency of about 50 Hz, a prototype of scavenging device is about 90 V AC peak-to-peak voltage and the durability of scavenging device is 9.715 years.

Durability of PZT at different environmental conditions plays a very important role for the continuous function of low power devices. The output of PZT may change when the working time increases in addition with the mechanical properties.

The purpose of the research activity is to identify the best configuration of piezoelectric (PZT) elements for a typical condition of wing aeroelastic instability. The attention is mainly focused on the flutter behavior of the structure. However, the model can be extended with low-impact adjustments to other loading conditions.

The dynamic system consists of a thin-walled beam, whose longitudinal faces are perfectly bonded by two PZT layers and it is excited by the aerodynamic forces to assume a simple harmonic oscillation motion. The equations of motion are obtained using an energy approach by applying the extended Hamilton principle in conjunction with the Ritz method for modal approximation. The external forces acting on the system are modeled according to the Theodorsen derivation.

The flutter speed and the power generated from flutter oscillations can be increased by acting on the length of the PZT elements. The results show that the model with the beam substrate totally covered by the PZT in its longitudinal direction is more effective for low electrical resistance, whereas for high resistance values, the beam substrate that is partially covered provides the best results. Furthermore, both flutter postponement and energy harvesting functions can be maximized by properly choosing the beam stiffness ratio.

Depending on the parameter we want to maximize, that is, the flutter speed or the energy harvested, it is possible to identify the best system configuration from the analysis presented in this paper.

The originality of the work appears in the sensitivity study performed on a three-dimensional piezo-aeroelastic fluttering wing, whose optimal behavior in terms of flutter postponement and power generation is analyzed using two distinct parameters, the beam stiffness ratio and the PZT length.

The characteristics of PZT suspensions have been studied and fit to stereolithography restraints. On one hand, researches concern the influence of fillers contents, dispersant concentration, temperature and resins nature and amount on suspensions rheological behaviour. On the other hand, the influence of photoinitiator and PZT concentrations, density of energy and nature of the resin on suspension reactivity was investigated. These experiments have led to the choice of two photosensitive suspensions suitable for stereolithography purpose; which use depend on the fillers content. Furthermore, the stereolithography process has been modified owing to the balance between suspensions rheological and photochemical properties in order to shape piezoelectric ceramics. Thanks to these improvements, PZT ceramics/polymer composites dedicated to transducers and medical imaging applications have been fabricated.

Reviews the inherent advantages, i.e. design flexibility and processing, of manufacturing piezoelectric ceramics and composites with numerous architectures via rapid prototyping techniques. Reports on processing in which piezoelectric ceramics and composites with novel and conventional designs were fabricated using rapid prototyping techniques. Fused deposition of ceramics, fused deposition modeling, and Sanders prototyping techniques were used to fabricate lead‐zirconate‐titanate ceramics and ceramic/polymer composites via, first, direct fabrication and, second, indirect fabrication using either lost mold or soft tooling techniques.

In this paper, a vibration measuring technique that relies on the use of piezoelectric material and is originally developed to measure the vibration of turbine blade is adopted to measure the vibration of cutting tool in turning. The piezoelectric material is embedded at the root of the cutting tool. The scope of this research is to investigate the feasibility of using this technique by first conducting ANSYS simulation to solve the coupled field equations that govern the piezoelectric phenomenon followed by experimental work to compare the measured data with those obtained by conventional method to have an insight into the effectiveness of the adopted technique. Both simulation and experimental results show that the use of an embedded PZT sensor at the root of cutting tool is very useful for measuring vibration and can be used for further cutting operation control. In addition, it has captured more information than conventional vibration measurement techniques.

Vibration measurement of root-embedded PZT material to convert the dynamic cutting forces into vibration signals that can be used in cutting process optimization and improvement of cutting quality.

PZT material is found to be very responsive to high-frequency vibrations such that it can catch Chatter phenomena and can be used in developing control strategies.

Mainly used for turning cutting process in this research. Other manufacturing process like milling special tool holder designs.

Can be used as online monitoring systems for cutting tool holders.

Engineer and technician aid in quality assurance and control.

The new approach of embedding PZT material at the cutting tool root and the signals presentation and processing.

The purpose of this paper is to present the problems of the electromechanical impedance (EMI), especially its applications for structural health monitoring of aircraft bolt-joints and innovative approach of EMI prediction at loosening of bolt-joints.

This experimental study includes the results of a full-scale test of the Mi-8 helicopter tail beam, particularly, its bolt-joints of a beam with other parts of the structure. One of the connecting frames of the tail beam was equipped with piezoelectric transducers (PZT) glued on the surface of the frame near the bolts. The bolts' loosening was investigated by using the EMI technology.

It was demonstrated that loosening of the bolt-joint produces a significant and statistically stable change of the EMI metric. Presumably, both the small shift of resonance frequencies and the EMI magnitude and resistance change are caused mainly by damping variation at the bolt-joint loosening. In this analytical study, the 2D model of a constrained PZT is proposed. In contrast with the existing model, the modal decomposition analysis is used as a universal mean to express the dynamic properties and dynamic responses of both the transducer and the host structure. This approach, together with the finite element modal analysis, allows simulation of any complex system “PZT-host structure”. The model can be easily transformed also to the 3D one. The bolt-joint of the Mi-8 helicopter with the EMI measurement system was simulated by using the developed 2D model. The simulation results satisfactorily correspond to the test.

The results of this research can be used for implementation in the structural health monitoring of bolt-joints and other aerospace structural components.

The new experimental results on aircraft real bolt-joints were obtained. Especially significant is the original 2D model of the electromechanical impedance, based on the modal decomposition method, which can significantly improve the accuracy and the realistic description of the dynamic interaction between PZT and structure, as well as the dynamic response to the appearance of structural damage.

The successful use of piezoceramic thick films in sensors and actuators requires a thorough understanding of their electrical and electromechanical characteristics. Since these characteristics depend not only on the material's composition but also on its compatibility with various substrates and a number of processing parameters, accurate measurements of the material's parameters are essential. Here, the aim of this paper is to present a procedure for characterising lead‐zirconate‐titanate (PZT) thick films on pre‐fired low‐temperature co‐fired ceramic (LTCC) substrates performed in order to determine the material parameters for numerical modelling.

Owing to the lack of standard procedures for measuring the elastic and piezoelectric properties of the films, the compliance parameters were evaluated from the results of nano‐indentation tests, and a substrate‐flexure method was used to evaluate the transverse piezoelectric coefficients.

The validation of the material model and the finite‐element (FE) analysis of the demonstrator sensor/actuator structures are shown to be in agreement with the FE model, even if not an exact fit.

This paper focuses on a characterisation of PZT thick films screen‐printed on pre‐fired LTCC substrates.