Shunted Piezoceramics Research Articles

Topology optimization of smart structures to enhance the performances of vibration control and energy harvesting

Abstract With the growing interest in smart materials, the utilization of shunted piezoceramics for dynamic vibration control has gained significant attention due to their unique characteristics, such as the ability to absorb strain energy from vibrating systems and convert it into electrical energy. Designing and analyzing the behavior of structures in hybrid mitigation/harvesting conditions, considering both reliability and performance, pose challenges. This paper aims to achieve optimal design parameters for the structure by employing a multiobjective optimization approach that strikes a compromise between maximizing harvested power and minimizing structural damage. To evaluate the effectiveness of the design, topology optimization was conducted in three different cases to compare the results. By systematically exploring the design space, these cases provide insights into the influence of various parameters on the structural performance. In addition, to enhance computational efficiency, the structure was represented as a metamodel using neural networks. This approach enables rapid evaluation and prediction of the structure’s behavior, facilitating the optimization process. By integrating multiobjective optimization, topology optimization, and metamodeling techniques, this study aims to provide valuable insights into the optimal design of structures that simultaneously incorporate shunt circuitry for vibration control and energy harvesting, leading to improved performance and reliability.

Passive Vibration Control of Plate-like Structures Using Shunted Piezoceramics

Application of piezoceramic materials in actuation and sensing of vibration is of current interest in active vibration control. The objective of this work is to investigate the gffect of shunted piezoceramics as passive vibration control devices when bonded to a host structure. The effect of orientation of the piezoceramic bonded onto the pLate is also investigated. Analytical studies are presented along with experimental results.

Robust passive control methodology and aeroelastic behavior of composite panels with multimodal shunted piezoceramics in parallel

The increasing use of composite materials in the aeronautical industry has made it possible to build lighter structures with better mechanical properties. Since lighter structures tend to be more flexible, undesirable vibrations and noise are increased and strategies that improve the aeroelastic stability are key issues to be addressed. With the use of intelligent materials, it is possible that the structure has the ability to dissipate energy and stabilize itself when subjected to external dynamic loadings imposed by airflow. This work demonstrates the feasibility of using a passive control tool to increase the supersonic flutter boundary of composite panels using a multimodal shunted piezoceramic in parallel topology. For an application of industrial interest, uncertainties in the electrical parameters of the shunt circuit are considered in the control system design. Numerical applications are presented and the main features and capabilities of the proposed methodology are highlighted.

Robust project of resonant shunt circuit for passive vibration control of composite structures

Composite structures have been widely used in petroleum, aerospace and automotive industries for which structural components must be designed to support high levels of mechanical disturbances with typically high reliability levels. Moreover, the increasing high-speed and lightweight composite structures subjected to vibrations, and the interest in achieving vibration attenuation becomes capital importance as extensive vibrations can reduce structural life and contribute to mechanical failure. In this sense, smart materials can be used as an excellent alternative, being able to stabilize these structures. Thus, the use of shunted piezoceramics has received major attention in the last decades. The contribution intended herein is the proposition of a robust passive vibration control tool by using resonant shunt circuits. The stochastic finite element method is used, and the uncertain variables are modeled as Gaussian random fields and discretized in accordance with the Karhunen–Loeve expansion method. Numerical applications are presented, and the main features and capabilities of the proposed method are highlighted.

Dynamic and aeroelastic behavior of composite plates with multimode resonant shunted piezoceramics in series

A better understanding and improvements on the dynamic and aeroelastic behaviors of composite structures by using active and passive control strategies are nowadays key issues in designing advanced lightweight aerospace structures with smaller levels of vibrations in order to perform their tasks with success, reliability and safety. However, since light structures tend to be more flexible, it is necessary that the structure itself shows the ability of dissipating energy and stabilizing itself when subjected to external dynamic loadings imposed by the airflow. In this sense, smart materials can be used as an excellent alternative, being able to stabilize these structures. The interest here is to investigate the possibility of increasing the supersonic flutter boundary of a composite flat panel by applying a multimode shunted piezoceramic in series topology, in which active control strategies cannot be easily performed. Despite the fact that much research on passive aeroelastic control strategies have been conducted in the open literature, few works have been suggested the use of multimode shunt circuits to deal with the flutter problem of aeroelectromechanical systems, which motivate the study reported herein.

Robust design of multimodal shunt circuits for vibration attenuation of composite structures

Composite materials are widely used in the development of many engineering products, especially in aerospace and automotive structures. It is due to their high strength/weight ratio and the possibility of obtaining the performance requirements of components. However, the increasing high-speed and lightweight composite structures subjected to vibrations, the interest in achieving vibration attenuation becomes of capital importance as extensive vibrations can reduce structural life and contribute to mechanical failure. Thus, the use of shunted piezoceramics has received major attention, as it is well adapted for space and automotive applications. The contribution intended here is the proposition of a robust optimisation strategy of multimode shunt circuits to increase their efficiency and robustness when uncertainties are presented. The maximum entropy principle is used to model the uncertainties and vulnerabilities are formulated to be optimised with the cost functions. Numerical applications are presented and the features and capabilities of the methodology are highlighted.

Tuning of a vibration absorber with shunted piezoelectric transducers

In order to reduce structural vibrations in narrow frequency bands, tuned mass absorbers can be an appropriate measure. A quite similar approach which makes use of applied piezoelectric elements, instead of additional oscillating masses, are the well-known resonant shunts, consisting of resistances, inductances, and possibly negative capacitances connected to the piezoelectric element. This paper presents a combined approach, which is based on a conventional tuned mass absorber, but whose characteristics can be strongly influenced by applying shunted piezoceramics. Simulations and experimental analyses are shown to be very effective in predicting the behavior of such electromechanical systems. The vibration level of the absorber can be strongly attenuated by applying different combinations of resistant, resonant, and negative capacitance shunt circuits. The damping characteristics of the absorber can be changed by applying a purely resistive or resonant resistant shunt. Additionally, the tuning frequency of the absorber can be adapted to the excitation frequency, using a negative capacitance shunt circuit, which requires only the energy to supply the electric components.

Vibration damping with shunted piezoceramics: Fundamentals and technical applications

This paper describes the damping performance of shunted piezoceramics for passive LR-networks, negative capacitance shunts (LRC) and the SSDI-switching technique. The calculations are based on a general description for mechanical structures with piezoelectric elements. Normalized parameters are introduced and the damping performance described by the generalized electromechanical coupling coefficient. For every electrical shunting the optimal network parameters are determined and the resulting maximum damping is compared.Additionally, a squealing disc brake and a bladed disc model are studied as technical applications. Practical realizations for the inclusion of the piezoelements and measurements are presented which validate the calculated damping performance. In particular, it is shown that the shunted piezoceramics are capable to suppress the brake squealing.

Flutter control using resistively shunted piezoceramics

AbstractThis paper investigates the feasibility of flutter control using resistively shunted piezoceramics. 2D aerofoil model is elastically restrained in heave and pitch by a set of leaf springs modeled as Bernoulli-Euler beams. The piezoceramic transducers are bonded to the leaf springs. Unsteady aerodynamic theory is used to solve the flutter determinant incorporating the additive damping terms due to resistive shunting. Tuned dampers realised by resistive shunted piezoceramics in heave and pitch springs could enhance flutter speed in the range 25-50 % based on additive damping of 10 % achieved due to resistive shunting of piezoceramics in either pitch spring, heave spring or both.

Brake squeal control with shunted piezoceramics — efficient modelling and experiments

Due to increased interest in comfort features, considerable effort has been spent on the modification of brake prototypes in order to suppress brake squeal. Recently, piezoelectric transducers have been investigated as an innovative way of controlling the vibrations of a brake. This paper presents an efficient mechanical model for the description of a brake with embedded transducers. Different control strategies are discussed and compared. Measurements on a brake test rig validate the obtained results.

Suppression of Brake Squeal Using Shunted Piezoceramics

Due to increased interest in comfort features, considerable effort is spent by brake manufacturers in order to suppress brake squeal. This process can be shortened by eliminating the remaining squealing with shunted piezoceramics that are embedded into the brake system. The piezoceramics offers the unique ability to convert mechanical energy into electrical energy and vice versa. The damping performance is determined by the connected shunt. This paper presents a multibody system model of a brake, which is capable of reproducing important features of brake squeal. It includes the dynamics of a piezoceramics that is shunted with a passive LR shunt or a negative capacitance LRC shunt. Analytical stability analysis is carried out to obtain optimal shunt parameters. The performance increase with a negative capacitance is studied in detail. The simulations are validated with measurements on an automotive disk brake.

Improvement of aeroelastic stability of hingeless helicopter rotor blade by passive piezoelectric damping

To augment weakly damped lag mode stability of a hingeless helicopter rotor blade in hover, piezoelectric shunt with a resistor and an inductor circuits for passive damping has been studied. A shunted piezoceramics bonded to a flexure of rotor blade converts mechanical strain energy to electrical charge energy which is dissipated through the resistor in the R-L series shunt circuit. Because the fundamental lag mode frequency of a soft-in-plane hingeless helicopter rotor blade is generally about 0.7/rev, the design frequency of the blade system with flexure sets to be so. Experimentally, the measured lag mode frequency is 0.7227/rev under the short circuit condition. Therefore the suppression mode of this passive damping vibration absorber is adjusted to 0.7227/rev. As a result of damping enhancement using passive control, the passive damper which consists of a piezoelectric material and shunt circuits has a stabilizing effect on inherently weakly damped lag mode of the rotor blades, at the optimum tuning and resistor condition.

BRAKE SQUEAL SUPPRESSION WITH SHUNTED PIEZOCERAMICS - A CONTROL FORMALISM

Brake squeal is a serious concern for brake manufacturers due to increased interest in comfort features. Up to date, brake squeal remains unpredictable, and brake design includes a time consuming process of designing, building and testing of prototypes. Shunted piezoceramics have been proven to be an alternative to suppress brake squeal. In this paper, shunt damping is treated as a collocated control. The analytic results are validated experimentally on a brake test rig.

VIBRATION CONTROL WITH SHUNTED PIEZOCERAMICS - THE ENERGY BALANCE

The paper presents the recent research on power and the energy balance in semi-active vibration control with shunted piezoceramics, where a negative capacitance circuit is involved. The work provides the general description of the piezoceramics as the power source element, which has the ability of converting the mechanical energy of the vibrating structure into the electrical energy, and by delivering it to the external shunt branch dissipates or generates the feedback reaction force damps the system.

Form factors for vibration control of beams using resistively shunted piezoceramics

The present work is motivated by a desire to investigate the effect of thickness and length ratios of the resistively shunted piezoceramic-host beam system on its ability to induce damping. Are there any optimal length and thickness ratios for which the additive damping due to piezoceramic resistive shunting is a maximum? Are these thickness and length ratios influenced by the boundary condition?

Structural vibration control using resistively shunted piezoceramics

Application of piezoceramic materials in actuation and sensing of vibration is of current interest. Potential and more popular applications of piezoceramics are probably in the field of active vibration control. However, the objective of this work is to investigate the effect of shunted piezoceramics as passive vibration control devices when bonded to a host structure. Resistive shunting of a piezoceramic bonded to a cantilevered duralumin beam has been investigated. The piezoceramic is connected in parallel to an electrical network comprising of resistors and inductors. The piezoceramic is a capacitor that stores and discharges electrical energy that is transformed from the mechanical motion of the structure to which it is bonded. A resistor across the piezoceramic would be termed as a resistively shunted piezoceramic. Similarly, an inductor across the piezoceramic is termed as a resonantly shunted piezoceramic. In this study, the effect of resistive shunting on the nature of damping enhancement to the host structure has been investigated. Analytical studies are presented along with experimental results.

Using passive techniques for vibration damping in mechanical systems

This paper examines two passive techniques for vibration reduction in mechanical systems: the first one is based on dynamic vibration absorbers (DVAs) and the second uses resonant circuit shunted (RCS) piezoceramics. Genetic algorithms are used to determine the optimal design parameters with respect to performance indexes, which are associated with the dynamical behavior of the system over selected frequency bands. The calculation of the frequency response functions (FRFs) of the composite structure (primary system + DVAs) is performed through a substructure coupling technique. A modal technique is used to determine the frequency response function of the structure containing shunted piezoceramics which are bonded to the primary structure. The use of both techniques simultaneously on the same structure is investigated. The methodology developed is illustrated by numerical applications in which the primary structure is represented by simple Euler-Bernoulli beams. However, the design aspects of vibration control devices presented in this paper can be extended to more complex structures.