@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} } @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} } @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} } @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{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} }