Stefan J. Rupitsch

Bio: Stefan J. Rupitsch is an academic researcher from University of Freiburg. The author has contributed to research in topics: Ultrasonic sensor & Computer science. The author has an hindex of 18, co-authored 160 publications receiving 1082 citations. Previous affiliations of Stefan J. Rupitsch include University of Erlangen-Nuremberg & Johannes Kepler University of Linz.

Inverse Method to estimate material parameters for piezoceramic disc actuators

Abstract: A novel Inverse Method for the determination of material parameters characterizing discoidal piezoceramic actuators is presented. In contrast to the common identification method, no specially shaped test samples are required. The Inverse Method is based on a finite element simulation. Both the measured mechanical and the electrical behavior of the actuator serve as input quantities of the new procedure. The presented results show the efficiency and correctness of the developed Inverse Method.

Complete characterization of piezoceramic materials by means of two block-shaped test samples

Abstract: We present an approach enabling entire characterization of piezoceramic materials. Contrary to the IEEE/ CENELEC Standard on Piezoelectricity, which is commonly applied for material characterization, the so-called inverse method requires only two block-shaped test samples. The method is based on a comparison of numerical simulations and measurement results for the frequency-resolved electrical impedance. Thereby, the aimed material parameters are iteratively updated so that simulations match measurements as well as possible. We utilize the identification procedure to characterize the piezoceramic material PIC255 as well as PIC155 from PI Ceramic, both of crystal class 6mm. In contrast to the parameters provided by the manufacturer, the identified data set leads to accurate simulation results for electrical and mechanical quantities of piezoceramic materials. This also holds if one predicts the behavior of geometrical shapes (e.g., disk) that are not considered within the inverse method. Moreover, we exploit the identification procedure to determine temperature dependences of the material parameters in the temperature range of –35°C to 130°C. To some extent, the parameters of PIC255 and PIC155 strongly depend on temperature. Nevertheless, the resulting electromechanical coupling factors for both materials remain nearly constant in the investigated temperature range.

A Preisach-based hysteresis model for magnetic and ferroelectric hysteresis

Abstract: In this paper we present a model for hysteretic nonlinearities with non-local memories. This model can be applied to describe hysteretic material behavior. Common applications are ferromagnetic or ferroelectric materials. Our model consists of an analytic function and a Preisach operator. We define a continuous Preisach weight function and introduce a method for the identification of the model parameters. The model parameters are customized to a set of symmetric hysteresis curves. We verify our model for a soft magnetic material, a hard magnetic material and the ferroelectric behavior of some piezoelectric material. After that, non-symmetric curves like the virgin curve are predicted very well by the model. It is especially useful, if forced magnetization or polarization, that appears beyond technical saturation, come into account.

Modeling and measurement of creep- and rate-dependent hysteresis in ferroelectric actuators

Abstract: We present a new model for the simulation of the hysteretic large-signal behavior in ferroelectric materials. The model is based on the Preisach operator and takes advantage of an analytic weight function for the underlying fundamental switching operators. The five independent parameters describing this weight function have been determined for a discoidal piezoceramic actuator by adapting the model output to measurements of the polarization. Since the classical Preisach model is only valid for creep- and rate-independent hysteresis loops, it is inappropriate to describe the entire ferroelectric material behavior. Therefore, we extended our model by an additional drift operator to consider creep phenomena. Furthermore, the rate-dependence of the hysteresis loops is described by a frequency-dependent parameter of the analytic weight function. For the identification and verification of the model, measurements have been performed using two different measurement principles: A modified Sawyer–Tower circuit as well as a method based on the integration of the electrical current. The agreement between measurements and simulations highlights the benefits of the enhanced hysteresis model.

Principles Of Optics Electromagnetic Theory Of Propagation Interference And Diffraction Of Light

Abstract: Thank you for reading principles of optics electromagnetic theory of propagation interference and diffraction of light. As you may know, people have search hundreds times for their favorite novels like this principles of optics electromagnetic theory of propagation interference and diffraction of light, but end up in harmful downloads. Rather than enjoying a good book with a cup of coffee in the afternoon, instead they are facing with some infectious bugs inside their computer.

Regularization Of Inverse Problems

Abstract: Thank you for downloading regularization of inverse problems. Maybe you have knowledge that, people have search hundreds times for their favorite novels like this regularization of inverse problems, but end up in malicious downloads. Rather than reading a good book with a cup of tea in the afternoon, instead they juggled with some infectious bugs inside their computer. regularization of inverse problems is available in our book collection an online access to it is set as public so you can download it instantly. Our book servers spans in multiple locations, allowing you to get the most less latency time to download any of our books like this one. Kindly say, the regularization of inverse problems is universally compatible with any devices to read.

An Experimental Study on the Effect of Temperature on Piezoelectric Sensors for Impedance-Based Structural Health Monitoring

Abstract: The electromechanical impedance (EMI) technique is considered to be one of the most promising methods for developing structural health monitoring (SHM) systems. This technique is simple to implement and uses small and inexpensive piezoelectric sensors. However, practical problems have hindered its application to real-world structures, and temperature effects have been cited in the literature as critical problems. In this paper, we present an experimental study of the effect of temperature on the electrical impedance of the piezoelectric sensors used in the EMI technique. We used 5H PZT (lead zirconate titanate) ceramic sensors, which are commonly used in the EMI technique. The experimental results showed that the temperature effects were strongly frequency-dependent, which may motivate future research in the SHM field.

Fundamentals And Applications Of Ultrasonic Waves

Abstract: fundamentals and applications of ultrasonic waves is available in our digital library an online access to it is set as public so you can download it instantly. Our book servers spans in multiple countries, allowing you to get the most less latency time to download any of our books like this one. Merely said, the fundamentals and applications of ultrasonic waves is universally compatible with any devices to read.