U. Marschner

TU Dresden | TUD

This paper presents a new mechanical network (lumped parameter circuit model) which enables the fast and easy modeling of a gyro sensor. In contrast to known network approaches, the proposed circuit is the first model, which takes full account of the fictitious force in a constant rotating frame of reference. The Coriolis force as well as the centr...

In this paper, the reversible transducer properties of a piezomagnetic unimorph are investigated experimentally and aggregated in a linear equivalent circuit. The unimorph consists of a single-crystal Galfenol plate, which is mounted to an aluminum plate. Such two-layer piezomagnetic elements are used in bending actuators or sensors. The completed...

Two-layer flexure beams often serve as basic transducers in actuators and sensors. In this paper a generalized description of their stimuli-influenced mechanical behavior is derived. For small deflection angles this description includes a multi-port circuit or network representation with lumped elements for a beam part of finite length. A number of...

Das vorliegende Fachbuch liefert detaillierte Einblicke in den Aufbau und die Aufgaben intelligenter und vernetzter Implantate. In Begleitung der Lehrbuchreihe Biomedizinische Technik vermittelt es Grundlagen zur Systemarchitektur vom biokompatiblen Sensorinterface bis zur Mensch-Maschine-Schnittstelle. Einen breiten Raum nimmt die Vorstellung aktu...

Das Buch enthält mehr als 130 Aufgaben und vollständig durchgerechneten Lösungen zur Schaltungsdarstellung – früher Ersatzschaltung –, Analyse und Simulation elektromechanischer und elektroakustischer Systeme. Es ergänzt das Lehrbuch "Elektromechanische Systeme der Mikrotechnik und Mechatronik" und geht dabei weit darüber hinaus mit Aufgaben zu pie...

In this paper, an equivalent mechanical chaotic signal generator, based on Chua’s circuit, is analyzed using the isomorphy between electrical and mechanical systems using the structure-true “2nd” analogy. It enables a timefficient behavioral system analysis with the help of well-established network methods without the need for extensive experintal...

Energy harvesting (EH) for tire pressure monitoring systems (TPMSs) is a key element to make tire sensors self-sufficient and to raise the features of vehicle tires to a next level. This work studies the commercially available piezoelectric flat transducers M2807-P1, M2807-P2 from SmartMaterials and P878.A1 and P876.SP1 from PI Ceramics to use the...

Stimuli-sensitive or responsive (smart) hydrogels, or chemofluidic transistors, are the base of the key control elements of smart chemomechanical valves. These valves have an outstanding potential for miniaturized, integrated sensor and actuator systems in many application areas and especially for lab-on-chip technology. Due to the multifaceted des...

Dielectric Elastomers (DE) considered as smart materials have increasing popularity in the scientific community. Despite a multitude of presented applications and devises based on DE, there is no standard model to describe them as transducers. Thus, their design is in general often time-consuming. To describe the operational behavior, mostly materi...

Stimuli‐sensitive hydrogels have an outstanding potential for miniaturized, integrated sensor, and actuator systems and especially for lab‐on‐chip technology, but the application is still in its infancy. One major reason may be that design and realization of hydrogel‐based systems are exceptionally complex and demanding. Here, the design parameters...

Despite great progress of lab‐on‐a‐chip (LoC) technology platforms in the last 30 years, there is a lack of standardized microfluidic components, real on‐chip automation and progressive functional scalability of the fluidic circuits. Hydrogel‐based microfluidic circuits have a high scaling potential and provide on‐chip automation, but are complex i...

Intelligent tires are one key element for autonomous self-driving cars and the Internet of Vehicles (IoV), especially if the battery-driven sensor systems attain the transition to be self-powered. Harvesting vibrational energy of these tire pressure monitoring systems (TPMSs) is the promising technique to make tire sensors self-sufficient and to pr...

This study presents a novel signal description based on stochastic signal analysis, applicable to electromagnetic, piezomagnetic or other transducers without energy storage as a capacitor. At present the peak power and average power are used to characterize the energy transducer. As for non-harmonic signals the last-mentioned quantities compress th...

The mechanics of medical endoscopes have not fundamentally changed over the last 40 years. Most endoscopes are manually operated through Bowden cables to control the head of the device, which is known to have major limitations. We propose a shape memory alloy actuated setup to enable computer-aided control. Before a complex manufacturing of porotyp...

Dielectric elastomer actuators show suitable properties to be utilized for dynamic applications, e.g. speakers, shakers and pumps, with possible benefits to existing conventional systems. In this work a method to predict the performance of dynamically actuated dielectric-elastomer roll-actuators (DERA) depending on both, material and design paramet...

Combined finite element and network modeling methods provide a time efficient instrument to simulate multi-physics systems. In this work, the Combined Simulation is applied to a nonlinear electromagnetic energy harvester with electrical interface circuit and capacitive energy storage. The energy harvester consists of two cylindrical permanent magne...

Recently, we could demonstrate positive effects of microfluidic cultivation conditions on maturation of cardiomyocytes derived from human induced pluripotent stem cells (iPS-CMs) in a 2D model. However, 3D cell culture models are much closer to physiological conditions. Combined with microfluidics, 3D systems should resemble the in-vivo conditions...

We propose a planar hydrogel-based micro-valve design which is modeled as a library element for Matlab Simulink. For this test case, a pressure pump (voltage source) in series with a micro-valve model (variable fluidic resistance) is built up. The micro-valve subsystem is separated in four main parts. Based on the applied temperature stimulus, the...

Electromechanical equivalent circuit models provide an efficient tool for analysis of power flow across multiple physical domains. This work applies this approach to analyze the dynamic behavior of magnetostrictive material-based devices. Here, the unimorph system consists of a magnetostrictive galfenol (Fe-Ga alloy) layer bonded to a non-magnetic...

The common methods to simulate acoustic components in a larger frequency band have significant restrictions. This leads to a limited applicabillity, especially for low frequency applications and acoustic microsystems. In this paper new approximation functions to describe the acoustic impedances of acoustic canal components with a circular or slit-s...

We propose an improved micro reactor design for a scalable microfluidic device, in which enzymes are immobilized in a hydrogel matrix. Furthermore, fluid flow is controlled by means of hydrogel-based micro-valves. In this work, computational flow simulations will be compared to experimental results to highlight new design ideas and to improve wetti...

Smart hydrogel micro-valves are essential components of micro-chemo-mechanical fluid systems. These valves are based on phase-changeable polymers. They can open and close micro-fluidic channels depending on the chemical concentration or the temperature in the fluid. A concept of finite element–based modeling in combination with network methods to s...

We propose a finite element model which describes the dynamic behavior of hydrogels for step-responses and quasi-static regimes. The material properties are implemented in a fluid structure interaction (FSI) model which simulates the swelling behavior of hydrogels within a micro-valve. The resulting volume change effects the fluid domain describing...

Temperature-responsive hydrogels are polymer particles whose equilibrium size depends on the temperature of the water they are immersed in. Here we present an equivalent circuit model of a temperature-controlled microvalve based on hydrogel particles. The resulting network model consists of three physical subsystems. The thermal subsystem considers...

Micro-valves play an important role in controlling and operating microfluidic systems. Utilizing stimuli-sensitive hydrogels facilitates the construction of smart micro-valves controlled by temperature, concentration (salt, organic solvent) or pH level. We propose a finite element model which uses the thermal domain as an auxiliary domain for the v...

A new equivalent circuit is presented, which describes the transport of a chemical solution with a certain concentration in a fluidic channel. Channels are basic parts of a microfluidic systems and the concentration of the chemical solution can control the opening and closing of valves based on smart hydrogels. This type of microfluidic systems fac...

Equivalent electromechanical circuit analysis models provide efficient tools for analysis of power flow across multiple physical domains. In this work, we use this tool to develop a model of the power flow through mechanical, magnetic and electrical domains for analysis of magnetostrictive material-based devices. The magnetostrictive unimorph syste...

This work concerns the modeling and dynamical study of a chemo-fluidic oscillator with the ability of coupling chemical and fluidic domains. The coupling is made possible by means of stimuli-responsive (also referred to as smart) hydrogels, which are able to change their volume under small variations of special thermodynamic parameters, in a revers...

In electromechanical measurement techniques, passive transducers and passive electrical networks often interact. In some applications, continua are considered as part of the system, where fields are formed and waves are propagated. In this article, networks, continua, and electromechanical transducers feature sufficient amplitude linear behavior in...

A chemofluidic oscillator circuit that employs a hydrogel-based chemofluidic transistor for chemical-fluidic coupling is presented. It shows a period between 200 and 1000 s and alcohol concentrations oscillating between 2 wt% and 10 wt%. Because of the direct interaction with chemistry, chemofluidic transistors have the potential to facilitate labs...

In article 1600005, Andreas Richter and co-workers present a chemofluidic oscillator circuit that employs a hydrogel-based valve, with the valves state dependent on the chemical composition of the liquid. Operating with constant fluidic sources the circuit generates oscillations of flow rates, pressures and chemical concentrations with excellent po...

Die Fakultät Elektrotechnik und Informationstechnik der TU Dresden hat eine lange Tradition auf dem Gebiet der Systemtheorie. Beginnend mit den Arbeiten von Walter Reichardt sind in Dresden auch bedeutsame Grundlagen für die Systemtheorie nichtelektrischer Systeme gelegt worden. Diese ermöglicht, aus der Struktur solcher Systeme Netzwerkmodelle abz...

Smart hydrogel micro-valves are essential components of micro-chemo-mechanical fluid systems. These valves show a transistor-like behavior and are based on phase-changeable polymers. They can open and close micro-fluidic channels depending on chemical concentrations in the fluid. These highly complex systems are challenging to engineer and their de...

Hydrogels consist of a network of cross-linked polymers that swell when put into water. For temperature-sensitive smart hydrogels the equilibrium hydrogel size depends on the temperature of the liquid. These hydrogels are used to build temperature-controlled fluidic valves. Here we present an equivalent circuit model of such a hydrogel valve. The t...

Prof. Dr.-Ing. habil. Wolf-Joachim Fischer vertritt seit 1994 als Professor an der Fakultät Elektrotechnik und Informationstechnik der Technischen Universität Dresden das Fachgebiet Mikrosystemtechnik. Am 2. Juni 2015 feiert er seinen 65. Geburtstag und nähert sich dem Abschied in den Ruhestand. Die Schwerpunkte seiner wissenschaftlichen Arbeiten w...

Die bisherige Netzwerkanalyse erfolgte ausschließlich für elektromechanische Systeme mit konzentrierten Bauelementen. Jetzt erfolgt die Erweiterung auf Systeme mit verteilten, also ortsabhängigen Parametern. Im Zeitbereich entspricht das dem Übergang von gewöhnlichen zu partiellen Differentialgleichungen. Diese Erweiterung ist für höhere Frequenzen...

Der elektrostatische Wandler gehört zur Gruppe der elektrischen Wandler und ist daher entsprechend Kapitel 5 durch ein gyratorisches Zweitor in Bild 5.2 gekennzeichnet.

Zur Erleichterung des Einstiegs in die Bearbeitung der anschließend aufgeführten Übungsaufgaben sind in diesem Abschnitt die wichtigsten Beziehungen zur Berechnung akustischer Netzwerke aufgeführt. Zur Vertiefung des Stoffes wird auf Abschnitt 3.3 im Lehrbuch [1] hingewiesen.

Die Kopplung von mechanischen und akustischen Netzwerken tritt besonders bei elektroakustischen, pneumatischen und hydraulischen Systemen auf. Kräfte und Bewegungen sollen akustische Drücke und Volumenflüsse erzeugen und umgekehrt. Im einfachsten Fall erfolgt diese Wandlung mit einem starren, masselosen Kolben in einem Rohr. In der Praxis werden me...

Die Aufgaben in den vorangegangenen Kapiteln behandeln ausschließlich lineare Netzwerke. Wesentliche Eigenschaften und Vorzüge dieser Betrachtungsweise sind im ersten Kapitel erklärt. Diese Vorzüge, wie Umkehrbarkeit der Wandler, die die Transformation von Netzwerkelementen über die Wandler hinweg erlaubt, oder die Beibehaltung einer Anregungsfrequ...

Der elektrodynamische Wandler gehört zur Gruppe der magnetischen Wandler und ist daher entsprechend Kapitel 5 durch eine transformatorische Verkopplung in Bild 5.2 gekennzeichnet. Das zugehörige Schaltbild des elektrodynamischen Wandlers ist in Bild 6.1 angegeben. Eine federnd aufgehängte Schwingspule bewegt sich in einem durch die magnetische Indu...

Das 6. und 7. Kapitel behandelt Übungsaufgaben zur besonders wichtigen Gruppe der elektromechanischen Wandler. Diese bilden den Kern der elektromechanischen Systeme und verknüpfen entsprechend Abschnitt 1.3, dargestellt in Bild 1.2, das mechanische und elektrische Teilnetzwerk reversibel miteinander. Dabei wird vorausgesetzt, dass die physikalische...

Zur Erleichterung des Einstiegs in die Bearbeitung der anschließend aufgeführten Übungsaufgaben sind in diesem Abschnitt die wichtigsten Beziehungen zur Berechnung translatorischer mechanischer Teilsysteme aufgeführt. Zur Vertiefung des Stoffes wird auf Abschnitt 3.1 im Lehrbuch [1] hingewiesen.

A novel pattern recognition algorithm is developed, which detects concentration of different gases automatically with impedance spectroscopy (IS) using a conducting poly sensor or a WO3 sensor. It consists of adaptive- simulated-annealing-supported-parameter-estimation (ASA-PE) for feature-extraction and committee-machine (CM) for classification. T...

In electromechanical measurement techniques, passive transducers and passive electrical networks often interact. In some applications, continua are part of the system, in which fields are formed and waves are propagated. If networks, continua and electromechanical transducers feature sufficient amplitude linear behavior in their environment (e.g.,...

Fiber-reinforced plastics for industrial applications face constantly increasing demands regarding efficiency, reliability, and economy. Furthermore, it was shown that fiber-reinforced plastics with tailored reinforcements are superior to metallic or monolithic materials. However, a trustworthy description of the load-specific failure behavior and...

The modeling and simulation of smart structures and systems involves coupled field calculations which cause currently high computational costs. Especially time and frequency analyses of sensor or actuator constructions described by equation systems with 10,000 to several 100,000 degrees of freedom demand efficient design methods. A successful appro...

This paper describes new active composite structures based on thermoplastic matrices which contain material homogeneous embedded piezoceramic modules. Starting point is the development of novel thermoplastic compatible piezoceramic modules, so called TPMs. By the utilization of the same matrix material for the composite structure and for the TPM ca...

Vibration analysis is a promising approach in order to detect early hip prosthesis loosening, with the potential to extend the range of diagnostic tools currently available in clinical routine. Ongoing research efforts and developments in the area of multi-functional implants, which integrate sensors, wireless power supply, communication and signal...

A method and a simplified analytical expression are presented for the calculation of the effective reluctance of a magnetic substrate underneath a planar coil as parameter in a simplified electromechanical network model. The investigated magnetic substrates have a toroid geometry with rectangular cross section, different thicknesses and permeabilit...

Fiber reinforced composites (FRP) for industrial applications face constantly increasing demands regarding efficiency, reliability and economy. Furthermore, it was shown that FRP’s with tailored reinforcements are superior to metallic or monolithic materials. However, a trustworthy description of load-specific failure behaviour and damage evolution...

Two-layer piezomagnetic elements within a homogeneous magnetic field have been well studied. In this paper the effect of an inhomogeneous magnetic field distribution in the magnetic layer on the electromechanical properties of a two-layer element with planar conductor arrangement on top is investigated. Based on static Finite Element (FE) simulatio...

Numerous vibrating electromechanical systems lack a rigid connection to the inertial frame. An artificial inertial frame can be generated by a shaker, which compensates for vibrations. In this article, we present an encapsulated and perforated unimorph bending plate for this purpose. Vibrations can be compensated up to the first eigenfrequency of t...

The healing process of bone fractures can be monitored by a measurement of the osteosynthesis plate bending. For this purpose a wireless magnetostrictive bending sensor is proposed. A planar rectangular coil on top of a magnetostrictive Galfenol (${\hbox {Fe}}_{83}{\hbox {Ga}}_{17}$ alloy) layer forms an electrical resonant circuit. The sensor is m...

Inductively coupled resonant sensors (ICR) are a class of wireless, passive sensors which can be used to monitor environmental parameters. Thereby a measurand alters the sensor resonance frequency through an inductance, capacitance and/or resistance change. When performing frequency domain measurements with a detection coil its parasitic capacitanc...

The combination of Network Methods and Finite Element Methods on user level is a time-efficient method for the simulation of dynamic behavior of electromechanical systems. Combined simulation can be structured into five areas of application: determination of network structures with FE-simulations, determination of network parameters with FEsimulati...

In this paper network methods and Finite-Element methods are combined to optimize the design of a piezoelectric sound generator. The FE-model is used to determine network parameters of the transducer model and finally the behavior of the chosen design variant. For the design optimization the network model is used. One design variant reaches a nomin...

A method is presented to determine the magnetic reluctance of a thin or a thick magnetic layer of permeability ¿ underneath a planar coil based on inductance measurements. The procedure is substantiated on the basis of the linear electromagnetic network model. The influence of the involved magnetic reluctances on the inductance is analyzed by a tr...

This paper analyzes a prototype microgyrosensor that employs the magnetostrictive alloy Galfenol for transduction of Coriolis-induced forces into an electrical output for quantifying a given angular velocity. The magnetic induction distribution in the Galfenol sensor patch depends on its bending shape and magnetoelastic properties and is investigat...

Galfenol Fe83Ga17 films are sputtered on Si wafers without, and with Ti or Ti/Cu metallic seed layers in order to obtain a magnetoelastic layer which is sensitive to bending deformations of the compound structure. The layer thicknesses range from 100 nm to 5 µm. Layer morphology, texture, and the Villari effect are examined. The texture of the Galf...

A new rotational magnetomechanical transducer network model for a magnetostrictive unimorph is presented. Often these laminated structures define an operating point about which the mechanical, magnetic and electrical quantities show only small variations and the behavior can be decribed by a linear model. It is shown how the magnetomechanical trans...

A magnetostrictive bending sensor with rectangular planar coil is investigated. Its purpose is to measure contactlessly mechanical quantities of non-vibrating structures using an alternating magnetic field. The coil turns are electrodeposited by pattern plating on top of a magnetostrictive Galfenol layer and a thin isolation layer. The coil turns i...

Electromechanical network models are used in this paper to analyze a prototype micro-gyro sensor that employs the magnetostrictive alloy GalFeNOL for transduction of Coriolis induced forces into an electrical output at a given angular velocity. The sensor is designed as a tuning fork structure which reacts with vibration of the prongs in tangential...

In this paper an electromechanical network model of a magnetostrictive unimorph structure, acting as solenoid coil core, is developed. For typical applications a non-uniform stress distribution in the magnetostrictive layer results which is simulated via FEM. This phenomenon leads to a spatial varying electromechanical transduction coefficient for...

Zusammenfassung Es wird ein Experimentalaufbau zur Anregung und drahtlosen Messung von Schwingungen einer teilweise in einen künstlichen Oberschenkelknochen einzementierten Hüftprothese vorgestellt. Um das dynamische Verhalten des mechanischen Systems zu diskutieren, wurde ein translatorisch-rotatorisches Netzwerkmodell erstellt. Mit diesem Modell...

The healing process of bone fractures can be monitored by a measurement of the osteosynthesis plate bending. An electrical resonant circuit consisting of a coil with a magnetostrictive Galfenol core and a capacitance enables an indirect wireless measurement of the plate bending. The Galfenol core is manufactured with a thin film technology using a...

A new solution for the integration of a wireless measurement system intended for the detection of hip prosthesis loosening by vibration analysis is presented. Small vibration amplitudes in the presence of noisy sensor signals of the excited prosthesis are measured with a digital lock-in amplifier which is integrated in the prosthesis together with...

Sputtered magnetostrictive Galfenol acts as sensing layer in a bending sensor based on a passive oscillating circuit. The change of the permeability is detected via a planar rectangular Cu inductor on top of the sensor. A Cu thin film beneath the Galfenol with Ti as adhesive promoter supports the growth of a (1 1 0) fiber texture which improves the...

Based on the inverse magnetostrictive effect a bending sensor for medical application was designed. The magnetostrictive sensor was fabricated with thin film technology and low temperature deposition processes. As the Galfenol thin film well as the sensor show the applicability for wireless deformation measurements. In a second step of sensor quali...

The measured magnetic induction field of a bar magnet can be used to compute or measure indirectly the position of the magnet. A model-based parameter estimation approach requires a precise induction field model and knowledge of the model error. In this paper, different analytic models describing the axial component of the induction field in front...

This paper presents a prototype micro-gyro sensor design that employs the new magnetostrictive alloy GalFeNOL for transduction of Coriolis induced forces into an electrical output. The concept takes advantage of the principles employed in vibratory gyro sensors and the ductile attributes of GalFeNOL to target high sensitivity and shock tolerance in...

A signal processing close to the sensor device makes it possible to realize functions like measurement processing, data compression, remote diagnosis and servicing, event driven measurement or the support of digital interfaces. Advantages and possibilities of such a solution will be explained on the basis of several application examples.

We describe different signal based feature extraction methods which we are using in an intelligent microsystem for machine vibration monitoring. Each of these methods enables a special view to the machine vibration signal. The statistical methods like the quadratic mean value and the percentiles are useful for a fast global view. Signal processing...

A new microsystem is presented which is able to process measurements including feature extraction and classification for local process monitoring. The heart of the microsystem is a 16-bit digital signal processor which can operate at up to 100 MIPS (million instructions per second). The extracted features are stored in a large non-volatile memory a...

A new, highly miniaturized hybrid integrated solution for telemetric pressure measurement in biomedical applications is presented. The telemetrically powered ITES (Implantable Telemetric Endo-System) consists of a surface micro-machined capacitive type absolute pressure sensor fabricated in an eight-mask MOS-like process and two low-power ASICs for...

In this paper we are describing the application of the Fuzzy Self-Organizing Map (FSOM) and some feature extraction methods to a intelligent microsystem for online machine vibration monitoring. We have developed such a microsystem with some of the most advanced semiconductor and microsystem technologies. On the basis of these technologies it is pos...

Advanced developments in the field of microelectronic and microsystem technologies together with powerful signal processing and soft computing algorithms are the basis for the realization of highly integrated intelligent microsystems. This paper describes such a intelligent microsystem for machine vibration monitoring. The first real world applicat...

The monitoring of a copper micro plating process by parameter estimation is investigated. The basis of the parameter estimation is a mathematical model of the relationship between electrical current density and potential which includes new approximations and which depends nonlinear on the parameters. The estimated parameters are used to adjust the...