@misc{ScharfenbergMottokArtmannetal., author = {Scharfenberg, Georg and Mottok, J{\"u}rgen and Artmann, Christina and Hobelsberger, Martin and Paric, Ivan and Großmann, Benjamin and Pohlt, Clemens and Wackerbarth, Alena and Pausch, Uli and Heidrich, Christiane and Fadanelli, Martin and Elsner, Michael and P{\"o}cher, Daniel and Pittroff, Lenz and Beer, Stefan and Br{\"u}ckl, Oliver and Haslbeck, Matthias and Sterner, Michael and Thema, Martin and Muggenthaler, Nicole and Lenck, Thorsten and G{\"o}tz, Philipp and Eckert, Fabian and Deubzer, Michael and Stingl, Armin and Simsek, Erol and Kr{\"a}mer, Stefan and Großmann, Benjamin and Schlegl, Thomas and Niedersteiner, Sascha and Berlehner, Thomas and Joblin, Mitchell and Mauerer, Wolfgang and Apel, Sven and Siegmund, Janet and Riehle, Dirk and Weber, Joachim and Palm, Christoph and Zobel, Martin and Al-Falouji, Ghassan and Prestel, Dietmar and Scharfenberg, Georg and Mandl, Roland and Deinzer, Arnulf and Halang, W. and Margraf-Stiksrud, Jutta and Sick, Bernhard and Deinzer, Renate and Scherzinger, Stefanie and Klettke, Meike and St{\"o}rl, Uta and Wiech, Katharina and Kubata, Christoph and Sindersberger, Dirk and Monkman, Gareth J. and Dollinger, Markus and Dembianny, Sven and K{\"o}lbl, Andreas and Welker, Franz and Meier, Matthias and Thumann, Philipp and Swidergal, Krzysztof and Wagner, Marcus and Haug, Sonja and Vernim, Matthias and Seidenst{\"u}cker, Barbara and Weber, Karsten and Arsan, Christian and Schone, Reinhold and M{\"u}nder, Johannes and Schroll-Decker, Irmgard and Dillinger, Andrea Elisabeth and Fuchshofer, Rudolf and Monkman, Gareth J. and Shamonin (Chamonine), Mikhail and Geith, Markus A. and Koch, Fabian and {\"U}hlin, Christian and Schratzenstaller, Thomas and Saßmannshausen, Sean Patrick and Auchter, Eberhard and Kriz, Willy and Springer, Othmar and Thumann, Maria and Kusterle, Wolfgang and Obermeier, Andreas and Udalzow, Anton and Schmailzl, Anton and Hierl, Stefan and Langer, Christoph and Schreiner, Rupert}, title = {Forschungsbericht 2015}, editor = {Baier, Wolfgang}, address = {Regensburg}, organization = {Ostbayerische Technische Hochschule Regensburg}, isbn = {978-3-00-048589-3}, doi = {10.35096/othr/pub-1386}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-13867}, language = {de} } @article{MonkmanSindersbergerPrem, author = {Monkman, Gareth J. and Sindersberger, Dirk and Prem, Nina}, title = {Magnetically enhanced photoconductive high voltage control}, series = {ISSS Journal of Micro and Smart Systems}, volume = {11}, journal = {ISSS Journal of Micro and Smart Systems}, publisher = {Springer Nature}, doi = {10.1007/s41683-021-00088-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-30606}, pages = {317 -- 328}, abstract = {The recent surge of interest in electrostatic actuators, particularly for soft robotic applications, has placed increasing demands on high voltage control technology. In this respect, optoelectronic bidirectional switching and analogue regulation of high voltages is becoming increasingly important. One common problem is the leakage current due to dark resistance of the material or device used. Another is the physical size of such elements. However, their ability to provide galvanic separation makes them a very attractive alternative to conventional (wired) semiconductor elements. This paper gives an overview of available methods and devices before introducing a concept based on the combination of photoresistive and magnetoresistive effects in Gallium Arsenide that are potentially applicable to other semiconductor materials.}, language = {en} } @article{MonkmanStrieglPremetal., author = {Monkman, Gareth J. and Striegl, Birgit and Prem, Nina and Sindersberger, Dirk}, title = {Electrical Properties of Magnetoactive Boron-Organo-Silicon Oxide Polymers}, series = {Macromolecular Chemistry and Physics}, volume = {221}, journal = {Macromolecular Chemistry and Physics}, number = {4}, publisher = {Wiley}, doi = {10.1002/macp.201900342}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-26488}, pages = {1 -- 8}, abstract = {The electrical properties of rheopectic magnetoactive composites comprising boron-organo-silicon oxide dielectric matrices containing carbonyl iron microparticles are presented for the first time. The increase in interfacial magnetocapacitance is seen to greatly exceed that experienced when using conventional elastomeric matrices such as polydimethylsiloxane. In addition to the increase in capacitance, a simultaneous and sharp decrease in the parallel electrical resistance over several orders of magnitude is also observed. The effects are time dependent but repeatable. Potential applications include magnetically controlled frequency dependent devices, magnetic sensor systems, weighting elements for neural networks, etc.}, language = {en} } @article{PremSindersbergerMonkman, author = {Prem, Nina and Sindersberger, Dirk and Monkman, Gareth J.}, title = {Infrared spectral analysis of low concentration magnetoactive polymers}, series = {Journal of Applied Polymer Science}, volume = {137}, journal = {Journal of Applied Polymer Science}, number = {7}, publisher = {Wiley}, organization = {WILEY}, issn = {1097-4628}, doi = {10.1002/app.48366}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-25913}, pages = {1 -- 7}, abstract = {This work concerns an area of magnetoactive polymer (MAP) research seldom considered. Traditionally only MAP with high concentrations of magnetic filler (typically between 10 and 90 wt\%) have been investigated. This article deals with a hitherto neglected aspect of research, namely MAP containing lower magnetic filler concentrations (1 to 3 wt\%). This article utilizes a range of spectroscopic analysis methods (Raman and FTIR) and their applicability to MAP characterization at wavelengths ranging from 2.5 to 25 mu m. Particular attention is paid to low carbonyl iron particle (CIP) concentrations in MAP for which the emergence of capillary doublets at a critical 2 wt\% concentration is revealed. This results in measurable magnetic field-dependent changes in IR absorption at a wavelength of 4.255 mu m together with a detectable CO2 susceptibility. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48366.}, language = {en} } @incollection{MonkmanBoeseErmertetal., author = {Monkman, Gareth J. and B{\"o}se, Holger and Ermert, Helmut and Klein, Dagmar and Freimuth, Herbert and Baumann, M{\´i}chael and Egersd{\"o}rfer, Stefan and Bruhns, Otto T. and Meier, Alexander and Raja, Kashif}, title = {Technologies for Haptic Systems in Telemedicine}, series = {Integration of Health Telematics into Medical Practice}, booktitle = {Integration of Health Telematics into Medical Practice}, editor = {Nerlich, Michael and Sch{\"a}chinger, Ulrich}, publisher = {IOS Press}, doi = {10.3233/978-1-60750-941-7-83}, pages = {83 -- 93}, abstract = {The ability to image the elastic properties of tissue is potentially useful in a variety of applications. The field of elastic imaging has grown in response to the Potential use of such information in medical diagnosis. Real time ultrasound elastography represents a recent development in determining strain and elasticity distributions. Nevertheless, commonly used imaging techniques rely on the interpretation of two dimensional visual data displayed on a video screen. In reality however, physicians often prefer tactile exploration making the simultaneous portrayal of both video and haptic information most desirable. Since the 1970's many alphanumeric to tactile data conversion methods have been investigated, mainly with the ultimate aim of assisting the blind. More recently, interest has been directed toward the display of pictures on haptically explorable surfaces - Tactile imaging. Such a system would allow surgeons to examine hard sectors contained within soft tissue, and thereby assist in operations held remotely. The expansion of ultrasound elastography to 3D formats would mean the ability to haptically explore regions of the body normally inaccessible to human hands. For three-dimensional imaging the acquisition of sequential tomographic slices using Elastography, combined with image segmentation, enables the reconstruction, quantification and visualisation of tumour volumes. In a collaborative project between four research Institutes, the aim is to produce a prototype three dimensional tactile displays comprising electrically switchable micromachined cells, whose mechanical moduli are governed by phase changes experienced by electrorheological and/or magnetorheological fluids. This will be integrated with a sensory ultrasonic elastography in order to present the human fingers with controllable surfaces capable of emulating biological tissue, muscle and bone.}, language = {en} } @article{BoeseBaumannMonkmanetal., author = {B{\"o}se, Holger and Baumann, Michael and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Tunayar, A. and Freimuth, Herbert and Ermert, Helmut and Khaled, W.}, title = {A new ER fluid based haptic actuator system for virtual reality}, series = {International journal of modern physics / B Condensed matter physics, statistical physics}, volume = {19}, journal = {International journal of modern physics / B Condensed matter physics, statistical physics}, number = {7-9}, publisher = {World Scientific Publ.}, doi = {10.1142/9789812702197_0129 [Titel anhand dieser DOI in Citavi-Projekt {\"u}bernehmen]}, pages = {1628 -- 1634}, abstract = {The concept and some steps in the development of a new actuator system which enables the haptic perception of mechanically inhomogeneous virtual objects are introduced. The system consists of a two-dimensional planar array of actuator elements containing an electrorheological (ER) fluid. When a user presses his fingers onto the surface of the actuator array, he perceives locally variable resistance forces generated by vertical pistons which slide in the ER fluid through the gaps between electrode pairs. The voltage in each actuator element can be individually controlled by a novel sophisticated switching technology based on optoelectric gallium arsenide elements. The haptic information which is represented at the actuator array can be transferred from a corresponding sensor system based on ultrasonic elastography. The combined sensor-actuator system may serve as a technology platform for various applications in virtual reality, like telemedicine where the information on the consistency of tissue of a real patient is detected by the sensor part and recorded by the actuator part at a remote location.}, language = {en} } @article{MonkmanEgersdoerferMeieretal., author = {Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Meier, Alexander and B{\"o}se, Holger and Baumann, Michael and Ermert, Helmut and Kahled, W. and Freimuth, Herbert}, title = {Technologies for Haptic Displays in Teleoperation}, series = {Industrial Robot}, volume = {30}, journal = {Industrial Robot}, number = {6}, publisher = {Emerald}, issn = {0143-991x}, doi = {10.1108/01439910310506792}, pages = {525 -- 530}, abstract = {Since the 1960s many alphanumeric to tactile data conversion methods have been investigated, mainly with the ultimate aim of assisting the blind. More recently, interest has been directed toward the display of pictures on haptically explorable surfaces - tactile imaging - for a range of medical, remote sensing and entertainment purposes. This paper examines the technologies which have been utilised for haptically explorable tactile displays over the past three decades, focussing on those which appear commercially viable in the immediate future.}, language = {en} } @article{BoeseMonkmanFreimuthetal., author = {B{\"o}se, Holger and Monkman, Gareth J. and Freimuth, Herbert and Tunayar, A. and Khaled, W. and Baumann, Michael and Egersd{\"o}rfer, Stefan and Ermert, Helmut}, title = {A new haptic sensor-actuator system based on electrorheological fluids}, series = {Actuator 2004 : 9th International Conference on New Actuators \& 3rd International Exhibition on Smart Actuators and Drive Systems ; Bremen, Germany, 14 - 16 June 2004}, journal = {Actuator 2004 : 9th International Conference on New Actuators \& 3rd International Exhibition on Smart Actuators and Drive Systems ; Bremen, Germany, 14 - 16 June 2004}, publisher = {HVG Hanseatische Veranstaltungs-GmbH}, address = {Bremen}, language = {en} } @inproceedings{BoeseMonkmanFreimuthetal., author = {B{\"o}se, Holger and Monkman, Gareth J. and Freimuth, Herbert and Tunayar, A. and Ermert, Helmut and Khaled, W. and Baumann, Michael and Egersd{\"o}rfer, Stefan}, title = {A new ER fluid based haptic actuator system for virtual reality}, series = {Proceedings of the Ninth International Conference Electrorheological Fluids and Magnetorheological Suspensions (ERMR 2004) : Beijing, China, 29 August - 3 September 2004}, booktitle = {Proceedings of the Ninth International Conference Electrorheological Fluids and Magnetorheological Suspensions (ERMR 2004) : Beijing, China, 29 August - 3 September 2004}, publisher = {World Scientific}, address = {Singapore}, pages = {889 -- 895}, language = {en} } @inproceedings{TunayarKleinFreimuthetal., author = {Tunayar, A. and Klein, Dagmar and Freimuth, Herbert and B{\"o}se, Holger and Baumann, Michael and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Ermert, Helmut and Khaled, W.}, title = {A tactile array based on electrorheological fluids}, series = {Actuator 2004 : 9th International Conference on New Actuators \& 3rd International Exhibition on Smart Actuators and Drive Systems, 14-16 June 2004, Bremen, Germany}, booktitle = {Actuator 2004 : 9th International Conference on New Actuators \& 3rd International Exhibition on Smart Actuators and Drive Systems, 14-16 June 2004, Bremen, Germany}, publisher = {HVG Hanseatische Veranstaltungs-GmbH}, address = {Bremen}, pages = {601 -- 604}, language = {en} } @inproceedings{BoeseErmertTunayaretal., author = {B{\"o}se, Holger and Ermert, Helmut and Tunayar, A. and Monkman, Gareth J. and Baumann, Michael and Kahled, W. and Reichling, S. and Bruhns, Otto T. and Freimuth, Herbert and Egersd{\"o}rfer, Stefan}, title = {A novel haptic sensor-actuator system for virtual reality}, series = {Eurohaptics 2004, Munich, Germany, June 5 - 7, 2004 Proceedings of the 4th International Conference EuroHaptics 2004 ; June 5 - 7, 2004, M{\"u}nchen, Germany}, booktitle = {Eurohaptics 2004, Munich, Germany, June 5 - 7, 2004 Proceedings of the 4th International Conference EuroHaptics 2004 ; June 5 - 7, 2004, M{\"u}nchen, Germany}, publisher = {Inst. of Automatic Control Engineering}, address = {M{\"u}nchen}, isbn = {3-9809614-0-0}, language = {en} } @inproceedings{BoeseErmertTunayaretal., author = {B{\"o}se, Holger and Ermert, Helmut and Tunayar, A. and Monkman, Gareth J. and Baumann, Michael and Kahled, W. and Reichling, S. and Bruhns, Otto T. and Freimuth, Herbert and Egersd{\"o}rfer, Stefan}, title = {A Novel Haptic Sensor-Actuator System for Applications in Virtual Reality}, series = {BMBF-Tagung, Leipzig 19.10 February 2004}, booktitle = {BMBF-Tagung, Leipzig 19.10 February 2004}, language = {en} } @inproceedings{BoeseMonkmanFreimuthetal., author = {B{\"o}se, Holger and Monkman, Gareth J. and Freimuth, Herbert and Klein, Dagmar and Ermert, Helmut and Baumann, Michael and Egersd{\"o}rfer, Stefan and Bruhns, Otto T.}, title = {ER Fluid Based Haptic System for Virtual Reality}, series = {Actuator 2002 : 8th International Conference on New Actuators \& 2nd International Exhibition on Smart Actuators and Drive Systems ; Bremen, Germany, 10 - 12 June 2002}, booktitle = {Actuator 2002 : 8th International Conference on New Actuators \& 2nd International Exhibition on Smart Actuators and Drive Systems ; Bremen, Germany, 10 - 12 June 2002}, edition = {CD-ROM}, pages = {351 -- 354}, language = {en} } @inproceedings{KhaledBruhnsReichlingetal., author = {Khaled, W. and Bruhns, Otto T. and Reichling, S. and B{\"o}se, Holger and Baumann, Michael and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Meier, Alexander and Klein, Dagmar and Freimuth, Herbert and Ermert, Helmut}, title = {A haptic system for virtual reality applications based on ultrasound elastography and electrorheological fluids}, series = {Acoustical Imaging (ACIM)}, volume = {27}, booktitle = {Acoustical Imaging (ACIM)}, publisher = {Springer}, address = {Dordrecht}, isbn = {978-90-481-6652-7}, issn = {0270-5117}, doi = {10.1007/978-1-4020-2402-3_85}, pages = {667 -- 674}, abstract = {Mechanical properties of biological tissue represent important diagnostic information and are of histological and pathological relevance. Malignant tumors are significantly stiffer and more immobile than surrounding healthy tissue. Hard calcifications in vessels occur due to arteriosclerosis. The problem is, that such information is usually not available or can only be obtained by manual palpation, which is subjective and limited in sensitivity. It requires intuitive assessment and does not allow quantitative documentation. Unfortunately, none of the established medical imaging equipment such as magnetic resonance imaging (MRI) or X-ray computed tomography (CT) can provide direct measure of tissue elasticity. On the one hand a suitable sensor is required for quantitative measurement of mechanical tissue properties. On the other hand there is also some need for a realistic haptic display of such tissue properties. Suitable actuator arrays with high spatial resolution acting in real time are required. A haptic sensor actuator system is presented in this paper including a sensitive sensor part and an actuator array for different applications. The mechanical consistency of an object is to be locally specified using a sensor system and represented perceptibly in a remote position on an actuator system for the user. The sensor system uses ultrasound (US) elastography, whereas the actuator array is based on electrorheological (ER) fluids.}, language = {en} } @inproceedings{KhaledBruhnsReichlingetal., author = {Khaled, W. and Bruhns, Otto T. and Reichling, S. and B{\"o}se, Holger and Baumann, Michael and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Meier, Alexander and Klein, Dagmar and Freimuth, Herbert and Ermert, Helmut}, title = {A haptic sensor-actuator-system based on ultrasound elastography and electrorheological fluids for virtual reality applications in medicine}, series = {CARS 2003 : computer assisted radiology and surgery ; proceedings of the 17th International Congress and Exhibition London, June 25 - 28, 2003}, booktitle = {CARS 2003 : computer assisted radiology and surgery ; proceedings of the 17th International Congress and Exhibition London, June 25 - 28, 2003}, publisher = {Elsevier}, address = {Amsterdam}, pages = {1354}, abstract = {Mechanical properties of biological tissue represent important diagnostic information and are of histological relevance (hard lesions, "nodes" in organs: tumors; calcifications in vessels: arteriosclerosis). The problem is, that such information is usually obtained by digital palpation only, which is limited with respect to sensitivity. It requires intuitive assessment and does not allow quantitative documentation. A suitable sensor is required for quantitative detection of mechanical tissue properties. On the other hand, there is also some need for a realistic mechanical display of those tissue properties. Suitable actuator arrays with high spatial resolution and real-time capabilities are required operating in a haptic sensor actuator system with different applications. The sensor system uses real time ultrasonic elastography whereas the tactile actuator is based on electrorheological fluids. Due to their small size the actuator array elements have to be manufactured by micro-mechanical production methods. In order to supply the actuator elements with individual high voltages a sophisticated switching and control concept have been designed. This haptic system has the potential of inducing real time substantial forces, using a compact lightweight mechanism which can be applied to numerous areas including intraoperative navigation, telemedicine, teaching, space and telecommunication.}, language = {en} } @article{KhaledErmertBruhnsetal., author = {Khaled, W. and Ermert, Helmut and Bruhns, Otto T. and Reichling, S. and B{\"o}se, Holger and Baumann, Michael and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Meier, Alexander and Klein, Dagmar and Freimuth, Herbert}, title = {Haptic sensor-actuator-system based on ultrasound elastography and electrorheological fluids for virtual reality applications in medicine}, series = {Studies in health technology and informatics, Medicine Meets Virtual Reality (MMVR)}, volume = {11}, journal = {Studies in health technology and informatics, Medicine Meets Virtual Reality (MMVR)}, number = {94}, publisher = {IOS Press}, pages = {144 -- 150}, abstract = {Mechanical properties of biological tissue represent important diagnostic information and are of histological relevance (hard lesions, "nodes" in organs: tumors; calcifications in vessels: arteriosclerosis). The problem is, that such information is usually obtained by digital palpation only, which is limited with respect to sensitivity. It requires intuitive assessment and does not allow quantitative documentation. A suitable sensor is required for quantitative detection of mechanical tissue properties. On the other hand, there is also some need for a realistic mechanical display of those tissue properties. Suitable actuator arrays with high spatial resolution and real-time capabilities are required operating in a haptic sensor actuator system with different applications. The sensor system uses real time ultrasonic elastography whereas the tactile actuator is based on electrorheological fluids. Due to their small size the actuator array elements have to be manufactured by micro-mechanical production methods. In order to supply the actuator elements with individual high voltages a sophisticated switching and control concept have been designed. This haptic system has the potential of inducing real time substantial forces, using a compact lightweight mechanism which can be applied to numerous areas including intraoperative navigation, telemedicine, teaching, space and telecommunication.}, language = {de} } @inproceedings{KhaledReichlingBruhnsetal., author = {Khaled, W. and Reichling, S. and Bruhns, Otto T. and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Baumann, Michael and B{\"o}se, Holger and Klein, Dagmar and Freimuth, Herbert and Tunayar, A. and Lorenz, A. and Pessavento, A. and Ermert, Helmut}, title = {Palpation imaging using a haptic system for virtual reality applications in medicine}, series = {Perspective in image-guided surgery : proceedings of the Scientific Workshop on Medical Robotics, Navigation, and Visualization : RheinAhrCampus Remagen, Germany, 11-12 March}, booktitle = {Perspective in image-guided surgery : proceedings of the Scientific Workshop on Medical Robotics, Navigation, and Visualization : RheinAhrCampus Remagen, Germany, 11-12 March}, publisher = {World Scientific Publ.}, address = {Singapore}, pages = {407 -- 414}, language = {en} } @inproceedings{KhaledReichlingBruhnsetal., author = {Khaled, W. and Reichling, S. and Bruhns, Otto T. and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Baumann, Michael and B{\"o}se, Holger and Klein, Dagmar and Freimuth, Herbert and Tunayar, A. and Lorenz, A. and Pessavento, A. and Ermert, Helmut}, title = {Palpation Imaging using a Haptic System for Virtual Reality Applications in Medicine}, series = {Proceedings of the 12th Annual Medicine Meets Virtual Reality Conference: - Building a Better You: The Next Tools for Medical Education, Diagnosis, and Care. - Medicine Meets Virtual Reality (MMVR) - Newport Beach (California, USA). 2004}, booktitle = {Proceedings of the 12th Annual Medicine Meets Virtual Reality Conference: - Building a Better You: The Next Tools for Medical Education, Diagnosis, and Care. - Medicine Meets Virtual Reality (MMVR) - Newport Beach (California, USA). 2004}, language = {en} } @inproceedings{KhaledBruhnsReichlingetal., author = {Khaled, W. and Bruhns, Otto T. and Reichling, S. and B{\"o}se, Holger and Baumann, Michael and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Meier, Alexander and Freimuth, Herbert and Tunayar, A. and Ermert, Helmut}, title = {A New Haptic Sensor Actuator System for Virtual Reality Applications in Medicine}, series = {Medical Image Computing and Computer-Assisted Intervention - MICCAI 2003: 6th International Conference, Montr{\´e}al, Canada, November 15-18, 2003, Proceedings}, booktitle = {Medical Image Computing and Computer-Assisted Intervention - MICCAI 2003: 6th International Conference, Montr{\´e}al, Canada, November 15-18, 2003, Proceedings}, publisher = {Springer}, isbn = {978-3540204626}, pages = {132 -- 140}, language = {en} } @article{KhaledBruhnsReichlingetal., author = {Khaled, W. and Bruhns, Otto T. and Reichling, S. and B{\"o}se, Holger and Baumann, Michael and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Meier, Alexander and Klein, Dagmar and Freimuth, Herbert and Ermert, Helmut}, title = {A haptic system for virtual reality applications based on ultrasound elastography and electrorheological fluids}, series = {Acoustical Imaging}, journal = {Acoustical Imaging}, number = {27}, publisher = {Kluver Academic}, address = {Dordrecht \& New York}, doi = {10.1007/978-1-4020-2402-3_85}, pages = {667 -- 675}, language = {en} } @inproceedings{KhaledReichlingBruhnsetal., author = {Khaled, W. and Reichling, S. and Bruhns, Otto T. and Ermert, Helmut and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Baumann, Michael and B{\"o}se, Holger and Freimuth, Herbert and Tunayar, A.}, title = {Palpation imaging using a haptic sensor actuator system for medical applications}, series = {Actuator 2004 : 9th International Conference on New Actuators \& 3rd International Exhibition on Smart Actuators and Drive Systems, 14-16 June 2004, Bremen, Germany}, booktitle = {Actuator 2004 : 9th International Conference on New Actuators \& 3rd International Exhibition on Smart Actuators and Drive Systems, 14-16 June 2004, Bremen, Germany}, publisher = {HVG Hanseatische Veranstaltungs-GmbH}, address = {Bremen}, pages = {379 -- 382}, language = {en} } @misc{PremSindersbergerMonkman, author = {Prem, Nina and Sindersberger, Dirk and Monkman, Gareth J.}, title = {Spectroscopic Analysis of Magneto-Active Polymers (MAP) - Poster}, series = {DFG-Tagung, Benediktbeuern, September 2017}, journal = {DFG-Tagung, Benediktbeuern, September 2017}, language = {en} } @misc{HecknerKesslerEgersdoerferetal., author = {Heckner, T. and Kessler, C. and Egersd{\"o}rfer, Stefan and Monkman, Gareth J.}, title = {Computer based platform for tactile actuator analysis}, series = {Actuator 2006 : 10th International Conference on New Actuators and 4th International Exhibition on Smart Actuators and Drive Systems, Bremen, Germany, 14 - 16 June 2006}, journal = {Actuator 2006 : 10th International Conference on New Actuators and 4th International Exhibition on Smart Actuators and Drive Systems, Bremen, Germany, 14 - 16 June 2006}, publisher = {HVG Hanseatische Veranst.-GmbH}, language = {en} } @misc{SindersbergerDiermeierMonkman, author = {Sindersberger, Dirk and Diermeier, Andreas and Monkman, Gareth J.}, title = {Investigation of the electrical properties of magneto-active polymers - Poster}, series = {DFG-Tagung, Benedikbeuern, September 2016}, journal = {DFG-Tagung, Benedikbeuern, September 2016}, language = {en} } @misc{MonkmanSindersberger, author = {Monkman, Gareth J. and Sindersberger, Dirk}, title = {Investigation of the electrical properties of magneto-active polymers}, series = {DFG-Tagung, Benedikbeuern, September 2015}, journal = {DFG-Tagung, Benedikbeuern, September 2015}, language = {en} } @incollection{NiklasHillerJaegeretal., author = {Niklas, Andreas and Hiller, Karl-Anton and J{\"a}ger, Andreas and Brandt, M. and Putzger, J{\"u}rgen and Ermer, C. and Schulz, Irene and Monkman, Gareth J. and Giglberger, Stephan and Hirmer, Marion and Danilov, Sergey N. and Ganichev, Sergey D. and Schmalz, Gottfried}, title = {In vitro optical detection of simulated blood pulse in a human tooth pulp model}, series = {Biocompatibility of Dental Materials}, booktitle = {Biocompatibility of Dental Materials}, editor = {Arenholt-Bindslev, Dorthe and Schmalz, Gottfried}, publisher = {Springer}, address = {Berlin ; Heidelberg}, language = {en} } @article{PremSindersbergerStriegletal., author = {Prem, Nina and Sindersberger, Dirk and Striegl, Birgit and B{\"o}hm, Valter and Monkman, Gareth J.}, title = {Shape memory effects using magnetoactive Boron-organo-silicon oxide polymers}, series = {Macromolecular Chemistry and Physics}, volume = {221}, journal = {Macromolecular Chemistry and Physics}, number = {15}, publisher = {Wiley}, doi = {10.1002/macp.202000149}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-23205}, pages = {1 -- 8}, abstract = {Thermomechanical shape memory materials have certain disadvantages when it comes to 3D volumetric reproduction intended for rapid prototyping or robotic prehension. The need to constantly supply energy to counteract elastic retraction forces in order to maintain the required geometry, together with the inability to achieve conformal stability at elevated temperatures, limits the application of thermal shape memory polymers. Form removal also presents problems as most viscoelastic materials do not ensure demolding stability. This work demonstrates how magnetoactive boron-organo-silicon oxide polymers under the influence of an applied magnetic field can be used to achieve energy free sustainable volumetric shape memory effects over extended periods. The rheopectic properties of boron-organo-silicon oxide materials sustain form removal without mold distortion.}, language = {en} } @article{MayerRabindranathBoerneretal., author = {Mayer, Matthias and Rabindranath, Raman and B{\"o}rner, Juliane and H{\"o}rner, Eva and Bentz, Alexander and Salgado, Josefina and Han, Hong and B{\"o}se, Holger and Probst, J{\"o}rn and Shamonin (Chamonine), Mikhail and Monkman, Gareth J. and Schlunck, G{\"u}nther}, title = {Ultra-Soft PDMS-Based Magnetoactive Elastomers as Dynamic Cell Culture Substrata}, series = {PLoS ONE}, volume = {8}, journal = {PLoS ONE}, number = {10}, publisher = {PLOS}, doi = {10.1371/journal.pone.0076196}, abstract = {Mechanical cues such as extracellular matrix stiffness and movement have a major impact on cell differentiation and function. To replicate these biological features in vitro, soft substrata with tunable elasticity and the possibility for controlled surface translocation are desirable. Here we report on the use of ultra-soft (Young's modulus <100 kPa) PDMS-based magnetoactive elastomers (MAE) as suitable cell culture substrata. Soft non-viscous PDMS (<18 kPa) is produced using a modified extended crosslinker. MAEs are generated by embedding magnetic microparticles into a soft PDMS matrix. Both substrata yield an elasticity-dependent (14 vs. 100 kPa) modulation of α-smooth muscle actin expression in primary human fibroblasts. To allow for static or dynamic control of MAE material properties, we devise low magnetic field (≈40 mT) stimulation systems compatible with cell-culture environments. Magnetic field-instigated stiffening (14 to 200 kPa) of soft MAE enhances the spreading of primary human fibroblasts and decreases PAX-7 transcription in human mesenchymal stem cells. Pulsatile MAE movements are generated using oscillating magnetic fields and are well tolerated by adherent human fibroblasts. This MAE system provides spatial and temporal control of substratum material characteristics and permits novel designs when used as dynamic cell culture substrata or cell culture-coated actuator in tissue engineering applications or biomedical devices.}, language = {en} } @article{ForsterMayerRabindranathetal., author = {Forster, Eva and Mayer, Matthias and Rabindranath, Raman and B{\"o}se, Holger and Schlunck, G{\"u}nther and Monkman, Gareth J. and Shamonin (Chamonine), Mikhail}, title = {Patterning of ultrasoft, agglutinative magnetorheological elastomers}, series = {Journal of applied polymer science}, volume = {128}, journal = {Journal of applied polymer science}, number = {4}, publisher = {Wiley}, address = {New York, NY}, doi = {10.1002/app.38500}, pages = {2508 -- 2515}, abstract = {A low-cost wax-cast molding technique for structuring ultrasoft (Young's modulus ≤ 40 kPa), agglutinative magnetorheological elastomer (MRE) material is presented. MRE structures ranging from a few millimeters down to the micrometer range with highly reproducible results are possible. Semitransparent MREs are also fabricated and their surfaces modified accordingly. This method opens new possibilities for MREs in biomedical engineering and microfluidic applications. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013}, language = {en} } @article{DiermeierSindersbergerKrenkeletal., author = {Diermeier, Andreas and Sindersberger, Dirk and Krenkel, Lars and Rosell, X. C. and Monkman, Gareth J.}, title = {Controllable Magnetoactive Polymer Conduit}, series = {The Open Mechanical Engineering Journal}, volume = {12}, journal = {The Open Mechanical Engineering Journal}, number = {1}, publisher = {Bentham}, pages = {192 -- 200}, abstract = {Objective: Magneto-active Polymers (MAP) are smart materials whose mechanical characteristics, such as elastic and shear moduli, may be controllable by means of an externally applied magnetic field. Methods: Various additives may be used to influence the characteristics of the polymer matrix whilst a suspension of soft and/or hard magnetic particles determine the magnetic properties of the composite. Both pre-cure and post-cure magnetization is possible. Results: A range of control strategies have been investigated for evaluation of the system using fluids of differing kinematic viscosity. Conclusion: Depending on the degree of magnetic field homogeneity, magneto-deformation and magnetostriction contribute to MAP actuation. This paper presents a novel application in the form of a peristaltic MAP tube system, applicable to flow control and pumping of hemorheological fluids in blood circulatory systems for biomedical research purposes.}, language = {en} } @article{LooNagarajuPathivadaetal., author = {Loo, Xuyan and Nagaraju, Bhavana and Pathivada, Sai and Bartsch, Alexander and Schratzenstaller, Thomas and Sattler, Robert and Monkman, Gareth J.}, title = {Electrical properties of bisphenol-A-free magnetoactive borosilicate polymers}, series = {AIP Advances}, volume = {14}, journal = {AIP Advances}, number = {5}, publisher = {AIP Publishing}, issn = {2158-3226}, doi = {10.1063/5.0203017}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-72936}, abstract = {The recent REACH regulations require the elimination of bisphenol-A and titanium dioxide from commercially available boron-based polymers. This has led to changes in some of the mechanical characteristics, which strongly influence the properties of magnetoactive borosilicate polymers. This work delivers results on the electrical properties and discusses some implications for future research using bisphenol-A and titanium-dioxide-free substitutes.}, language = {en} } @article{KleinFreimuthMonkmanetal., author = {Klein, Dagmar and Freimuth, Herbert and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and Meier, Alexander and B{\"o}se, Holger and Baumann, Michael and Ermert, Helmut and Bruhns, Otto T.}, title = {Electrorheological Tactile Elements}, series = {Mechatronics}, volume = {15}, journal = {Mechatronics}, number = {7}, publisher = {Pergamon}, address = {Oxford}, doi = {10.1016/j.mechatronics.2004.05.007}, pages = {883 -- 897}, abstract = {The use of ultrasound systems for medical examination and diagnosis is nothing new. The extension of ultrasound techniques for real time elastographic analysis purposes represents a more recent development. Nevertheless, as they stand all such techniques rely on the interpretation of two-dimensional visual data displayed on a video screen. In reality however, a medical doctor will make as much use of exploratory touch as he or she does vision, making the simultaneous portrayal of both video and tactile information most desirable [B{\"o}se H, Monkman GJ, Freimuth H, Ermert H. Haptisches Sensor-Aktor-System uaf der grundlage der Echtzeitelastographie sowie von elktro- und magnetorheologischen Materialien "HASASEM" [3]. BMBF Antrag 01 IR A14D, Oktober 2000]. This paper discusses the preliminary tests and basic design parameters for single tactels using electrorheological fluids. The final aim is to produce a prototype three-dimensional tactile display comprising electrically switchable micro-machined cells whose mechanical moduli are governed by phase changes experienced by electrorheological fluids. This will be integrated with the latest elastographic ultrasonic sensor systems in order to present the human fingers with controllable surfaces capable of emulating biological tissue, muscle and bone.}, language = {en} } @article{KleinRensinkFreimuthetal., author = {Klein, Dagmar and Rensink, D. and Freimuth, Herbert and Monkman, Gareth J. and Egersd{\"o}rfer, Stefan and B{\"o}se, Holger and Baumann, Michael}, title = {Modelling the Response of a Tactile Array using an Electrorheological Fluids}, series = {Journal of Physics D: Applied Physics}, volume = {37}, journal = {Journal of Physics D: Applied Physics}, number = {5}, publisher = {IOP Publ.}, address = {Bristol}, issn = {1361-6463}, doi = {10.1088/0022-3727/37/5/023}, pages = {794 -- 803}, abstract = {This paper reports the first step in the development of a tactile array suitable for the presentation of haptic information in virtual reality. The system is based on the electric field dependence of the viscosity of electrorheological fluids. The simulation, as well as the experimental realization of single tactels is described. The mathematical approach is based on the Eckart model (Eckart W 2000 Continuum Mech. Thermodyn. 12 341-62) and its validity is demonstrated by comparing the resulting yield stress with the experimental results from Wunderlich (2000 Dissertation Universit{\"a}t Erlangen-N{\"u}rnberg). Two different tactel designs are realized and the experimental results are compared with numerical simulation. The design of modification B is shown to be applicable for the realization of an actuator array with high spatial resolution.}, language = {en} } @inproceedings{DiermeierSindersbergerMonkman, author = {Diermeier, Andreas and Sindersberger, Dirk and Monkman, Gareth J.}, title = {Magneto-Active Polymer Actuator}, series = {Actuator 16 : 15th International Conference on New Actuators \& 9th International Exhibition on Smart Actuators and Drive Systems : conference proceedings}, booktitle = {Actuator 16 : 15th International Conference on New Actuators \& 9th International Exhibition on Smart Actuators and Drive Systems : conference proceedings}, publisher = {WFB}, address = {Bremen}, isbn = {978-3-933339-26-3}, pages = {286 -- 289}, abstract = {Magneto-active Polymers (MAP) are closely related to magneto-rheological fluids in that they contain magnetic micro-particles. However, instead of being freely suspended in a carrier fluid they are physically bound within a highly elastic polymer-matrix. The application of an external magnetic field allows changes in the mechanical properties, such as elastic and shear moduli, of the composite material to be achieved. The colossal magneto-rheological effect has been shown to demonstrate changes in Young's modulus by over 1E6 \%. Current research concentrates on controllable compliance and the resulting shape memory properties of MAP. This paper deals with recent advancements in this respect, including tubular magneto-active devices with potential applications in medical and other technology.}, language = {en} } @article{MonkmanBoody, author = {Monkman, Gareth J. and Boody, F. P.}, title = {Ein Vergleich verschiedene Master-Programme}, series = {Die Neue Hochschule}, journal = {Die Neue Hochschule}, number = {1}, publisher = {DUZ Verlags- und Medienhaus GmbH}, address = {Berlin}, pages = {12 -- 13}, language = {de} } @article{DillingerMayerSchneideretal., author = {Dillinger, Andrea Elisabeth and Mayer, Matthias and Schneider, Magdalena and Weber, Gregor R. and Goeppner, Corinna and Tamm, Ernst R. and Shamonin (Chamonine), Mikhail and Monkman, Gareth J. and Fuchshofer, Rudolf}, title = {Reactive changes in optic nerve astrocytes are mediated by CTGF, TGF beta 2 and increasing substratum stiffness}, series = {Investigative ophthalmology \& visual science}, volume = {56}, journal = {Investigative ophthalmology \& visual science}, number = {7}, publisher = {ASSOC RESEARCH VISION OPHTHALMOLOGY INC}, abstract = {Purpose: Patients with primary open-angle glaucoma (POAG) show a stiffer peripapillary sclera, reactive astrocytes and a remodeled lamina cribrosa (LC). The changes are thought to be mediated by TGFβ2 and its downstream mediator CTGF. Recently we developed a murine glaucoma model by overexpressing CTGF in the anterior eye (βb1CTGF). In this study we investigated the glial lamina region of βb1CTGF mice, and the changes of astrocytes in response to CTGF and TGFβ2 as well as increasing substratum stiffness. Methods: Tangential sections of the glial LC of 2-month-old βb1CTGF mice and their wild-type littermates (WT) were stained with phalloidin and antibodies against GFAP, CTGF and fibronectin (FN). Murine optic nerve (ON) astrocytes from CD1 mice were isolated, cultured and characterized by GFAP staining. The astrocytes were treated with TGFβ2 (1ng/ml) and CTGF (50ng/ml and 100ng/ml). In addition, the cells were seeded on PDMS substrata with different stiffness (10, 30 and 60 kPa). Treated cells were analyzed by Western blotting, real-time RT-PCR and immunohistochemistry. Wound healing assays were performed to analyze migration rate following growth factor treatment. Results: βb1CTGF mice showed a massive increase in CTGF and GFAP in the glial LC when compared with WT mice. Moreover, an increase in FN staining and phalloidin-labeled actin was observed in the peripapillary sclera. Murine ON astrocytes reacted on increased substrate stiffness by increasing the synthesis of GFAP, vimentin and CTGF. Treatment of the cells with TGFβ2 and CTGF led to an enhanced migration rate. In addition, treatment resulted in an increased expression and synthesis of ECM proteins, including FN, tropoelastin, collagen type I and III. The in vitro findings correlated with those seen in the glaucoma mouse model. Conclusions: We conclude that changes in the ECM of LC and peripapillary sclera alter their biomechanical properties and thereby induce reactive changes in resident astrocytes. The reactive changes induced by higher stiffness of their surrounding ECM give rise to a self-amplifying process that includes increased TGFβ2/CTGF signaling and leads to synthesis of ECM and cytoskeletal proteins, a process that in turn augments the stiffness at the optic nerve head (ONH). Such a scenario may finally result in a vicious circle as the causative mechanism for ONH deformation in POAG.}, language = {en} } @article{SorokinStepanovShamoninChamonineetal., author = {Sorokin, Vladislav V. and Stepanov, Gennady V. and Shamonin (Chamonine), Mikhail and Monkman, Gareth J. and Khokhlov, Alexei R. and Kramarenko, Elena Yu}, title = {Hysteresis of the viscoelastic properties and the normal force in magnetically and mechanically soft magnetoactive elastomers: Effects of filler composition, strain amplitude and magnetic field}, series = {Polymer}, volume = {76}, journal = {Polymer}, publisher = {Elsevier}, doi = {10.1016/j.polymer.2015.08.040}, pages = {191 -- 202}, abstract = {Hysteresis in dynamic modulus, loss factor and normal forces of magnetoactive elastomers (MAEs) comprising various proportions of small (3-5 mu m) and large (50-60 mu m) ferromagnetic particles are experimentally studied using dynamic torsion performed at a fixed oscillation frequency in varying DC magnetic fields. It is shown that hysteresis is a characteristic feature of MAEs observed both under increasing/decreasing magnetic field strength and increasing/decreasing strain amplitude. This hysteresis is attributed to the specific rearrangement of the magnetic filler network under simultaneously applied magnetic field and shear deformation. Rheological properties of the magnetic filler network formed in the magnetic field and, therefore, the rheological properties of MAEs depend strongly on the filler composition and the magnetic field magnitude. Larger magnetic particles and higher magnetic fields provide stronger magnetic networks. Both factors result in the extension of the linear viscoelastic regime to larger strain amplitudes and lead to higher values of shear storage and loss moduli. It is found that the hysteresis width maximises at an intermediate magnetic field where it is attributed to the balance between elastic and magnetic particle interactions. This is apparently where the most significant restructuring of the magnetic network occurs. The hysteresis width decreases with increasing fraction of large particles in the magnetic filler. The loss factor grows significantly when the magnetic network is physically broken by large strains gamma > 1\%. A huge (more than one order of magnitude) increase of normal force at maximum magnetic field strengths is observed. It is predicted that any physical quantity depending on the internal structuring of the magnetic filler should demonstrate hysteresis either with a changing magnetic field and constant deformation amplitude or under variable deformation in a constant magnetic field. (C) 2015 Elsevier Ltd. All rights reserved.}, language = {en} } @article{MonkmanSindersbergerDiermeieretal., author = {Monkman, Gareth J. and Sindersberger, Dirk and Diermeier, Andreas and Prem, Nina}, title = {The magnetoactive electret}, series = {smart materials and structures}, volume = {26}, journal = {smart materials and structures}, number = {7}, publisher = {IOP Publishing}, doi = {10.1088/1361-665X/aa738f}, abstract = {A magnet which adheres to every surface, not only those of ferromagnetic materials, has hitherto been the domain of science fiction. Now for the first time such a novel device exists. The fusion of a permanently magnetized magnetoactive polymer containing hard magnetic particles and an electret enhanced with ferroelectric particles has resulted in the development of a new smart device-the magnetoactive electret. Magnetoactive electrets can be made to exhibit the usual magnetic properties of permanent magnetism together with the electrostatic properties of electrets. This results in simultaneous magnetoadhesion and electroadhesion forces from the same elastomeric element. The biasing field, needed to avoid discontinuities concerned with transition through the zero point in operating curves, is normally provided by means of either a magnetic or an electric field. This novel technology provides both bias options in a single device.}, language = {en} } @article{MonkmanSindersbergerPremetal., author = {Monkman, Gareth J. and Sindersberger, Dirk and Prem, Nina and Diermeier, Andreas and Szecsey, Tamara}, title = {Dielectric behaviour of magnetic hybrid materials}, series = {Physical Sciences Reviews}, volume = {7}, journal = {Physical Sciences Reviews}, number = {10}, publisher = {de Gruyter}, doi = {10.1515/psr-2019-0121}, pages = {1169 -- 1185}, abstract = {The objectives of this work include the analysis of electrical and magnetic properties of magneto-elastic hybrid materials with the intention of developing new techniques for sensor and actuator applications. This includes the investigation of dielectric properties at both low and high frequencies. The behaviour of capacitors whose dielectrics comprise magnetic hybrid materials is well known. Such interfacial magnetocapacitance can be varied according to magnetic content, magnetic flux density and the relative permittivity of the polymer matrix together with other dielectric content. The basic function of trapping electrical charges in polymers (electrets) is also established technology. However, the combination of magnetoactive polymers and electrets has led to the first electromagnetic device capable of adhering to almost any material, whether magnetically susceptible or not. During the course of this research, in addition to dielectrics, electrically conductive polymers based on (PDMS) matrices were developed in order to vary the electrical properties of the material in a targeted manner. In order to ensure repeatable results, this demanded new fabrication techniques hitherto unavailable. The 3D printing of silicones is far from being a mature technology and much pioneering work was necessary before extending the usual 3 d.o.f. to include orientation about and diffusion of particles in these three axes, thus leading to the concept of 6D printing. In 6D printing, the application of a magnetic field can be used during the curing process to control the particulate distribution and thus the spatial filler particle density as desired. Most of the devices (sensors and actuators) produced by such methods contain levels of carbonyl iron powder (CIP) embedded magnetic filler of up to 70 wt\%. Contrary to this, a hitherto neglected research area, namely magnetoactive polymers (MAPs) having significantly lower magnetic particle concentrations (1 to 3 wt\% CIP) were also investigated. With filler concentrations lower than 3 wt\%, structures are formed which are completely absent at higher filler levels. CIP concentrations in the range of 1wt\% demonstrate the formation of toroidal structures. Further development of coherent rings with a compact order results as filler concentrations increase towards 2 wt\%. Above 3 wt\% the structure eventually disintegrates to the usual random order found in traditional MAP with higher CIP content. Structured samples containing 1\%-3 wt\% CIP were investigated with the aid of X-ray tomography where solitary ring structures can be observed and eventually the formation of capillary doubles. Over wavelengths ranging from 1 to 25 µm, spectroscopic analysis of thin film MAP samples containing 2 wt\% CIP revealed measurable magnetic-field-dependent changes in IR absorption at a wavenumber 2350 (λ = 4.255 µm). This was found to be due to the diamagnetic susceptibility of atmospheric carbon dioxide (CO2). Consequently, the first potential application for sparse matrix MAPs was found.}, language = {en} } @article{PremSindersbergerMonkman, author = {Prem, Nina and Sindersberger, Dirk and Monkman, Gareth J.}, title = {Mini-Extruder for 3D Magnetoactive Polymer Printing}, series = {Advances in Materials Science and Engineering}, journal = {Advances in Materials Science and Engineering}, publisher = {HINDAWI}, doi = {10.1155/2019/8715718}, pages = {1 -- 8}, abstract = {This work describes the development of a new miniature extruder, essential to cavity-free 3D printing of silicone-based smart materials. This makes the 3D printing of magnetoactive and electroactive polymer soft robotic components and devices directly from CAD data possible. The special feature of such an extruder is that it is designed for use with addition-crosslinking RTV-2 silicones, including solid particulate additives. The extruder merges the respective components automatically during extrusion which obviates the need for premixing and vacuum evacuation. Problems associated with inhomogeneities and unwanted cavity production are consequently eliminated. Rheological details necessary to the design, together with some preliminary performance results, are presented.}, language = {en} } @article{KreitmeierChashinFetisovetal., author = {Kreitmeier, Florian and Chashin, Dmitri V. and Fetisov, Yuri K. and Fetisov, Leonid Y. and Schulz, Irene and Monkman, Gareth J. and Shamonin (Chamonine), Mikhail}, title = {Nonlinear Magnetoelectric Response of Planar Ferromagnetic-Piezoelectric Structures to Sub-Millisecond Magnetic Pulses}, series = {Sensors}, volume = {12}, journal = {Sensors}, number = {11}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/s121114821}, pages = {14821 -- 14837}, abstract = {The magnetoelectric response of bi- and symmetric trilayer composite structures to pulsed magnetic fields is experimentally investigated in detail. The structures comprise layers of commercially available piezoelectric (lead zirconate titanate) and magnetostrictive (permendur or nickel) materials. The magnetic-field pulses have the form of a half-wave sine function with duration of 450 µs and amplitudes ranging from 500 Oe to 38 kOe. The time dependence of the resulting voltage is presented and explained by theoretical estimations. Appearance of voltage oscillations with frequencies much larger than the reciprocal pulse length is observed for sufficiently large amplitudes (~1-10 kOe) of the magnetic-field pulse. The origin of these oscillations is the excitation of bending and planar acoustic oscillations in the structures. Dependencies of the magnetoelectric voltage coefficient on the excitation frequency and the applied magnetic field are calculated by digital signal processing and compared with those obtained by the method of harmonic field modulation. The results are of interest for developing magnetoelectric sensors of pulsed magnetic fields as well as for rapid characterization of magnetoelectric composite structures.}, language = {en} } @article{MonkmanSindersbergerPremetal., author = {Monkman, Gareth J. and Sindersberger, Dirk and Prem, Nina and Szecsey, Tamara}, title = {Smart Stiction}, series = {Robotics \& Automation Engineering Journal}, volume = {4}, journal = {Robotics \& Automation Engineering Journal}, number = {4}, publisher = {Juniper Publishers}, doi = {10.19080/RAEJ.2019.04.555641}, abstract = {Soft robotics could loosely be described as the engineering science of expanded dexterity through controllable flexibility. The exploitation of controllable compliance through the judicious choice of soft flexible members, as opposed to a finite number of rigid kinematic joints, can result in greater dexterity without compromising simplicity. One example is the replacement of segmented mechanical legs with simple compliant material eruciform prolegs. To achieve this in robotics, without introducing additional mechanical joints, mobile surfaces with switchable coefficients of friction is essential. This paper explains how, using silicone based smart materials, the rapid alternation between kinematic and static friction (stiction) may be achieved.}, language = {en} } @article{SindersbergerPremMonkman, author = {Sindersberger, Dirk and Prem, Nina and Monkman, Gareth J.}, title = {Structure formation in low concentration magnetoactive polymers}, series = {AIP advances}, volume = {9}, journal = {AIP advances}, number = {3}, publisher = {AIP Publishing}, doi = {10.1063/1.5079997}, abstract = {This paper concerns recent research into the autonomous formation of micro-structures in low carbonyl iron powder (CIP) concentration magneto active polymers (MAP). Higher concentrations of CIP show an isotropic distribution of magnetic filler throughout the entire sample, while autonomous structure formation is possible at mass concentrations lower than 3\%. The formation of micro-toroids commences as CIP concentration approaches 1\% wt. Further development of coherent rings with a defined order follow as CIP concentrations increase toward 2\% wt, whilst exceeding 3\% wt leads to the same isotropic distribution found in higher concentration MAP. Structured samples containing between 1\% wt and 3\% wt CIP were investigated using X-Ray tomography where solitary structures could clearly be observed. The ring structures represent microinductivities whose geometries can be manipulated during fabrication. In addition, these structures are magnetic field sensitive. This is not only relevant to applications in the GHz and THz areas but recent research has revealed implications for optical, thermal, acoustic and even chemical MAP sensors. (C) 2019 Author(s).}, language = {en} } @article{ChenZhangSongetal., author = {Chen, Rui and Zhang, Zhuo and Song, Ruizhou and Fang, Cheng and Sindersberger, Dirk and Monkman, Gareth J. and Guo, Jianglong}, title = {Time-dependent electroadhesive force degradation}, series = {Smart Materials and Structures}, volume = {29}, journal = {Smart Materials and Structures}, number = {5}, publisher = {IOP Publishing}, doi = {10.1088/1361-665X/ab79b5}, abstract = {This paper concerns a comprehensive investigation of time-dependent electroadhesion (EA) force degradation. EA shear force tests on different object materials (a PET, glass, ABS, and wood plate) have shown that force degradation was dominated by residual polarization charges trapped in the EA pad dielectric rather than in the substrate dielectric from which the object to be prehended is made. In order to explain this dynamic physical phenomenon, a model of dielectric polarization and depolarization has been proposed. According to the derived relationship between EA force and discharge time, three different methods intended to mitigate this problem has been compared: (1) the natural discharge method, (2) the high voltage resistor discharge method, and (3) the discharge prior to field polarity reversal method. These methods are useful for generating repeatable and stable EA forces, which are required for the characterization of EA pads and their subsequent employment in material handling, mobile robot crawling and climbing tasks.}, language = {en} } @article{SchmidtStraubSindersbergeretal., author = {Schmidt, Henrik and Straub, Benedikt B. and Sindersberger, Dirk and Br{\"o}ckel, Ulrich and Monkman, Gareth J. and Auernhammer, G{\"u}nter}, title = {Collision and separation of nickel particles embedded in a Poly dimethylsiloxan matrix under a rotating magnetic field: A strong magneto active function}, series = {Colloid and Polymer Science}, volume = {299}, journal = {Colloid and Polymer Science}, publisher = {Springer}, doi = {10.1007/s00396-020-04784-4}, pages = {955 -- 967}, abstract = {In order to function as soft actuators, depending on their field of use, magnetorheological elastomers (MREs) must fulfill certain criteria. To name just a few, these can include rapid response to external magnetic fields, mechanical durability, mechanical strength, and/or large deformation. Of particular interest are MREs which produce macroscopic deformation for small external magnetic field variations. This work demonstrates how this can be achieved by just a small change in magnetic field orientation. To achieve this, (super)paramagnetic nickel particles of size ≈ 160 μm were embedded in a non-magnetic polydimethylsiloxan (PDMS) (661-1301 Pa) and their displacement in a stepwise rotated magnetic field (170 mT) recorded using a video microscope. Changes in particle aggregation resulting from very small variations in magnetic field orientation led to the observation of a new strongly magneto-active effect. This configuration is characterized by an interparticle distance in relation to the angle difference between magnetic field and particle axis. This causes a strong matrix deformation which in turn demonstrates hysteresis on relaxation. It is shown that the occurrence strongly depends on the particle size, particle distance, and stiffness of the matrix. Choosing the correct parameter combination, the state can be suppressed and the particle-matrix system demonstrates no displacement or hysteresis. In addition, evidences of non-negligible higher order magnetization effects are experimentally ascertained which is qualitatively in agreement with similar, already theoretically described, particle systems. Even at larger particle geometries, the new strongly magneto-active configuration is preserved and could create macroscopic deformation changes.}, language = {en} } @inproceedings{SeflProchazkaHalleretal., author = {Sefl, Ondrej and Prochazka, Radek and Haller, Rainer and Monkman, Gareth J.}, title = {Alternative Approach to Optical Detection of Partial Discharges in Air}, series = {2021 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP): 12-15 Dec. 2021, Vancouver, BC, Canada}, booktitle = {2021 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP): 12-15 Dec. 2021, Vancouver, BC, Canada}, publisher = {IEEE}, isbn = {978-1-6654-1907-9}, issn = {2576-2397}, doi = {10.1109/CEIDP50766.2021.9705350}, pages = {324 -- 327}, abstract = {This article compares the standard electrical method of partial discharge detection with a novel optical detection method based on silicon photomultipliers. A third, complementary, single-loop antenna method is added to represent the ultra-high frequency method commonly used in gas-insulated switchgear/lines. A trio of air-insulated electrode designs that simulate the fundamental fault/discharge types in gaseous insulation (protrusion - corona discharge, floating conductive particle, surface discharges) are employed. Phase-resolved partial discharge activity patterns are compiled for each electrode design. The patterns are analyzed using spatial statistics and the interpretation of the obtained data trends explained by means of an example. Ultimately, the consistency and reliability of discharge detection by the optical methods for each fault/discharge type are evaluated, and suggestions for improvement are made.}, language = {en} } @inproceedings{SindersbergerPremMonkmanetal.2021, author = {Sindersberger, Dirk and Prem, Nina and Monkman, Gareth J. and Zimmermann, Klaus}, title = {Self-Sensing Electroadhesive Polymer Gripper with Magnetically Controllable Surface Geometry}, series = {Actuator 2021, International Conference and Exhibition on New Actuator Systems and Applications: GMM conference, February 17-19, 2021, online event}, booktitle = {Actuator 2021, International Conference and Exhibition on New Actuator Systems and Applications: GMM conference, February 17-19, 2021, online event}, editor = {Schlaak, Helmut}, publisher = {VDE VERLAG}, address = {Berlin; Offenbach}, isbn = {9783800754540}, doi = {10.1002/macp.201800222}, pages = {318 -- 320}, year = {2021}, abstract = {Compared to conventional end effectors, electro-adhesive grippers enable the handling of sensitive, soft or air-permeable materials [1]. The prehension force is based on a strong electric field generated by electrodes resulting in a polarisation of the dielectric and the generation of mirror charges in the workpiece. When the electrode supply voltage is deactivated, the electric field drops,but an electrostatic field remains due to remanent polarisation of the dielectric. The residual charge on the gripper surface reduces only slowly and in combination with other influencing factors can prevent the workpieces from being ejected temporarily or completely. In this work a solution to this problem is presented by means of gripper surface deforming caused by the applicat ion of a magnetic field to a magneto- active polymer (MAP) actuator. The in-creased distance between the workpiece and the dielectric enables precise and controlled ejection. In addition to compliance and deformability, the employment of soft smart materials enables the integration of self-sens-ing mechanisms for the measurement of surface deformation. The embedding of electrically conductive flexible electrodes within the soft silicone dielectric sup port such movements and serves as the n ecessary electrodes for electroadhesion. Since the implementation of the end effectoris based entirely on soft materials, the self-sensing magnetically controllable electroadhesive gripper (SMEG) can be produced in a shape deposition manufacturing (SDM) process [2], [3] and is highly applicable to the field of soft robotics.}, language = {de} } @article{SorokinEckerStepanovetal., author = {Sorokin, Vladislav V. and Ecker, Eva and Stepanov, Gennady V. and Shamonin (Chamonine), Mikhail and Monkman, Gareth J. and Kramarenko, Elena Yu and Khokhlov, Alexei R.}, title = {Experimental study of the magnetic field enhanced Payne effect in magnetorheological elastomers}, series = {Soft Matter}, volume = {10}, journal = {Soft Matter}, number = {43}, publisher = {ROYAL Society of CHEMISTRY}, doi = {10.1039/c4sm01738b}, pages = {8765 -- 8776}, abstract = {The dynamic modulus and the loss factor of magnetorheological elastomers (MREs) of various compositions and anisotropies are studied by dynamic torsion oscillations performed in the absence and in the presence of an external magnetic field. The emphasis is on the Payne effect, i.e. the dependence of the elastomer magnetorheological characteristics on the strain amplitude and their evolution with cyclically increasing and decreasing strain amplitudes. MREs are based on two silicone matrices differing in storage modulus (soft, G' similar to 10(3) Pa, and hard, G' similar to 10(4) Pa, matrices). For each matrix, the concentration of carbonyl iron particles with diameters of 3-5 mu m was equal to 70 and 82 mass\% (22 and 35 vol\%, respectively) in the composite material. Samples for each filler content, isotropic and aligned-particles, are investigated. It is found that the Payne effect significantly increases in the presence of an external magnetic field and varies with the cyclical loading which reaches saturation after several cycles. The results are interpreted as the processes of formation-destruction-reformation of the internal filler structure under the simultaneously applied mechanical force and magnetic field. Impacts of matrix elasticity and magnetic interactions on the filler alignment are elucidated.}, language = {en} } @article{ChenSongZhangetal., author = {Chen, Rui and Song, Ruizhou and Zhang, Zhuo and Bai, Long and Liu, Fuqiang and Jiang, Pei and Sindersberger, Dirk and Monkman, Gareth J. and Guo, Jianglong}, title = {Bio-Inspired Shape-Adaptive Soft Robotic Grippers Augmented with Electroadhesion Functionality}, series = {Soft Robotics}, volume = {6}, journal = {Soft Robotics}, number = {6}, publisher = {Mary Ann Liebert}, doi = {10.1089/soro.2018.0120}, pages = {701 -- 712}, abstract = {Soft robotic grippers (SRGs) have been extensively employed in robotic grasping and manipulation applications due to the fact that they are beneficial for pick-and-place of difficult-to-handle and delicate objects with various geometries and stiffness in a comfortable and safer way. This article presents a bio-inspired and shape-adaptive SRG augmented with electroadhesion (EA) functionality, FinEA, by a cost-effective combination of a Fin Ray structured two-fingered SRG with two soft-stretchable EA pads. The EA pads were manufactured by screen printing a layer of electrically conductive and elastomeric carbon black powder mixed with polydimethylsiloxane onto a dielectric substrate. The compliant Fin Ray fingers, composed of soft longitudinal beams and rigid cross beams, were structurally optimized by the finite element method using ABAQUS/CAE based on three key parameters: the open angle of the longitudinal beams, the spacing between the cross beams, and the incline angle of the cross beams. The soft beams were produced by a traditional soft lithography method, whereas the rigid cross beams were three-dimensionally printed. The resultant FinEA grippers were capable of lifting not only flat/thin materials without distorting them due to the employment of EA, but also concave and convex objects due to the passively shape-adaptive Fin Ray structure and the EA functionality. In addition, the proposed FinEA grippers were able to grasp delicate materials and objects whose diameters are larger than the overall gripper length. Furthermore, 65\% more weight in shear were picked up by the FinEA gripper when 4 kV was applied compared with 0 V. The FinEA concept provides useful and alternative solution for controllable adhesion-based SRGs and may facilitate the inspiration and development of future SRGs with added functionality and enhanced versatility.}, language = {en} } @article{DiermeierSindersbergerAngeleetal., author = {Diermeier, Andreas and Sindersberger, Dirk and Angele, Peter and Kujat, Richard and Monkman, Gareth J.}, title = {Sensor system for use with low intensity pulsed ultrasound}, series = {Sensor review}, volume = {39}, journal = {Sensor review}, number = {6}, publisher = {Emerald}, issn = {0260-2288}, doi = {10.1108/SR-11-2018-0304}, pages = {828 -- 834}, abstract = {Purpose Ultrasound is a well-established technology in medical science, though many of the conventional measurement systems (hydrophones and radiation force balances [RFBs]) often lack accuracy and tend to be expensive. This is a significant problem where sensors must be considered to be "disposable" because they inevitably come into contact with biological fluids and expense increases dramatically in cases where a large number of sensors in array form are required. This is inevitably the case where ultrasound is to be used for the in vitro growth stimulation of a large plurality of biological samples in tissue engineering. Traditionally only a single excitation frequency is used (typically 1.5 MHz), but future research demands a larger choice of wavelengths for which a single broadband measurement transducer is desirable. Furthermore, because of implementation conditions there can also be large discrepancies between measurements. The purpose of this paper deals with a very cost-effective alternative to expensive RFBs and hydrophones. Design/methodology/approach Utilization of cost-effective piezoelectric elements as broadband sensors. Findings Very effective results with equivalent (if not better) accuracy than expensive alternatives. Originality/value This paper concentrates on how very cost-effective piezoelectric ultrasound transducers can be implemented as sensors for ultrasound power measurements with accuracy as good, if not better than those achievable using radiation force balances or hydrophones.}, language = {en} } @article{SindersbergerPremMonkman, author = {Sindersberger, Dirk and Prem, Nina and Monkman, Gareth J.}, title = {Self-assembling structure formation in low-density magnetoactive polymers}, series = {Journal of Applied Polymer Science}, volume = {137}, journal = {Journal of Applied Polymer Science}, number = {3}, publisher = {Wiley}, doi = {10.1002/app.48291}, abstract = {The formation of microstructures in magnetoactive polymers (MAPs) is a recently discovered phenomenon found only with very low filler particle concentrations (less than 3 wt \%). Due to the degassing process, filler particles collect around an ascending bubble, which dissolves at a certain point leaving particulate rings within the matrix. The formation of toroidal microstructures commences as filler concentration approaches 1 wt \%. The development of coherent parallel aligned rings with a compact order continues as particle concentrations increase toward 2 wt \%. Between 2 and 3 wt \% capillary doublets develop, while mass percentages higher than 3\% result in increasing entropy as the random order of particle agglomeration found in higher concentration MAP dominates. Self-structured samples of different filler material and concentrations between 1 and 3 wt \% have been investigated using X-ray tomography, where the emerging structures can be observed and visualized. The ring structures resulting from this research represent microinductivities which can be fabricated in a targeted manner, thus enabling new applications in the high-frequency radio field. Furthermore, these anisotropic, but well-organized, structures have magnetic field-dependent implications for optical, thermal, acoustic, and medical applications.}, language = {en} } @inproceedings{EgersdoerferZeidlerWieseretal., author = {Egersd{\"o}rfer, Stefan and Zeidler, A. and Wieser, A. and Trompier, F. and Monkman, Gareth J. and Shamonin (Chamonine), Mikhail}, title = {A portable accident dosimeter using tooth enamel}, series = {Proceedings of the 7th International Symposium on EPR Dosimetry and Applications and the 2nd International Conference on Biodosimetry held at the Uniformed Services University of the Health Sciences, Bethesda, MD, USA, 10-13 July 2006}, booktitle = {Proceedings of the 7th International Symposium on EPR Dosimetry and Applications and the 2nd International Conference on Biodosimetry held at the Uniformed Services University of the Health Sciences, Bethesda, MD, USA, 10-13 July 2006}, publisher = {Pergamon}, address = {Oxford}, language = {en} } @book{MonkmanHesseSteinmannetal., author = {Monkman, Gareth J. and Hesse, Stefan and Steinmann, Ralf and Schunk, Henrik}, title = {Robot Grippers}, publisher = {Wiley}, isbn = {9783527406197}, doi = {10.1002/9783527610280}, abstract = {Since robotic prehension is widely used in all sectors of manufacturing industry, this book fills the need for a comprehensive, up-to-date treatment of the topic. As such, this is the first text to address both developers and users, dealing as it does with the function, design and use of industrial robot grippers. The book includes both traditional methods and many more recent developments such as micro grippers for the optolectronics industry. Written by authors from academia, industry and consulting, it begins by covering the four basic categories of robotic prehension before expanding into sections dealing with endeffector design and control, robotic manipulation and kinematics. Later chapters go on to describe how these various gripping techniques can be used for a common industrial aim, with details of related topics such as: kinematics, part separation, sensors, tool excahnge and compliance. The whole is rounded off with specific examples and case studies. With more than 570 figures, this practical book is all set to become the standard for advanced students, researchers and manufacturing engineers, as well as designers and project managers seeking practical descriptions of robot endeffectors and their applications.}, language = {en} } @article{SorokinStepanovShamoninChamonineetal., author = {Sorokin, Vladislav V. and Stepanov, Gennady V. and Shamonin (Chamonine), Mikhail and Monkman, Gareth J. and Kramarenko, Elena Yu}, title = {Magnetorheological behavior of magnetoactive elastomers filled with bimodal iron and magnetite particles}, series = {Smart materials and structures}, volume = {26}, journal = {Smart materials and structures}, number = {3}, publisher = {IOP Publishing}, doi = {10.1088/1361-665X/26/3/035019}, abstract = {Magnetoactive elastomers (MAE) based on soft silicone matrices, filled with various proportions of large diameter ( approximately 50 mu m) iron and small diameter ( approximately 0.5 mu m) magnetite particles are synthesized. Their rheological behavior in homogeneous magnetic fields up to 600 mT is studied in detail. The addition of small magnetite particles facilitates fabrication of uniformly distributed magnetic elastomer composites by preventing aggregation and sedimentation of large particles during curing. It is shown that using the proposed bimodal filler particles it is possible to tailor various magnetorheological (MR) properties which can be useful for different target applications. In particular, either absolute or relative magnetorheological effects can be tuned. The value of the damping factor as well as the range of deformation amplitudes for the linear viscoelastic regime can be chosen. The interdependencies between different MR properties of bimodal MAEs are considered. The results are discussed in the model framework of particle network formation under the simultaneous influence of external magnetic fields and mechanical deformation.}, language = {en} }