@techreport{SieglEhrlichSiegletal., author = {Siegl, Marco and Ehrlich, Ingo and Siegl, Marco and Ehrlich, Ingo}, title = {Einfluss von Prozessparametern auf die Schmelzimpr{\"a}gnierung zur Herstellung von faserverst{\"a}rkten Thermoplasten}, series = {Forschung 2018 / Ostbayerische Technische Hochschule Regensburg}, journal = {Forschung 2018 / Ostbayerische Technische Hochschule Regensburg}, editor = {Baier, Wolfgang}, publisher = {VMK Verlag f{\"u}r Marketing \& Kommunikation GmbH \& Co. KG}, organization = {Ostbayerische Technische Hochschule Regensburg}, pages = {72 -- 73}, abstract = {Die Erforschung von faserverst{\"a}rkten Kunststoffen (FVK) mit thermoplastischer Matrix ist aufgrund der Schweißeignung als Verbindungstechnologie, der thermischen Umformbarkeit, der Recyclebarkeit sowie der verk{\"u}rzten Prozesszeiten im Vergleich zu den vorwiegend eingesetzten faserverst{\"a}rkten Duroplasten erstrebenswert. Die Wechselwirkung zwischen den physikalischen, mechanischen und geometrischen Parametern erh{\"o}ht den Komplexit{\"a}tsgrad des Herstellungsprozesses. Ziel ist daher die Entwicklung einer Impr{\"a}gniertechnik, die eine Fasertr{\"a}nkung mittels eines Thermoplastschmelzbades erm{\"o}glicht.}, language = {de} } @misc{OlbrichPongratzBierletal., author = {Olbrich, Florian and Pongratz, Christian and Bierl, Rudolf and Ehrlich, Ingo}, title = {Method and System for Evaluating a Structural Integrity of an Aerial Vehicle}, series = {Europ{\"a}isches Patentblatt (09.12.2020) zur Anmeldung: OTH Regensburg, Anmeldenummer: 19179054.2, Patentnummer 1001/3748327, Ver{\"o}ffentlichungsnummer: 3 748 327}, journal = {Europ{\"a}isches Patentblatt (09.12.2020) zur Anmeldung: OTH Regensburg, Anmeldenummer: 19179054.2, Patentnummer 1001/3748327, Ver{\"o}ffentlichungsnummer: 3 748 327}, pages = {395 -- 396}, language = {en} } @article{ValentinoSgambitterraFurgiueleetal., author = {Valentino, Piergiorgio and Sgambitterra, Emanuele and Furgiuele, Franco and Romano, Marco and Ehrlich, Ingo and Gebbeken, Norbert}, title = {Mechanical characterization of basalt woven fabric composites}, series = {Frattura ed Integrit{\`a} Strutturale (Fracture and Structural Integrity)}, volume = {8}, journal = {Frattura ed Integrit{\`a} Strutturale (Fracture and Structural Integrity)}, number = {28}, doi = {10.3221/IGF-ESIS.28.01}, pages = {1 -- 11}, abstract = {Basalt fabric composite, with different twill wave reinforcements, i.e. twill 2/2 and twill 1/3, have been studied in this work by means of experimental tests and numerical finite element (FE) simulations. As fabric reinforcements show repeating undulations of warp and fill yarn, simple mixtures law cannot be applied. As a consequence, the mesoscopic scale, lying between the microscopic and the macroscopic one, has to be taken into account to mechanically characterize a fabric reinforced composite. The aim of this work is to evaluate the stiffness of a fabric reinforced composite in warp and fill direction. In particular a numerical FE model, assuming elliptical sections and sinusoidal shape of the yarns, has been implemented and experimental tests have been carried out in order to validate the proposed model. Finally, the strength and the failure modes le orientation, have been experimentally investigated.}, language = {en} } @inproceedings{SchmidBrulandEhrlichetal., author = {Schmid, Vinzent and Bruland, Matthias and Ehrlich, Ingo and Kastenmeier, Andreas}, title = {Entwicklung und Regelung eines hydraulischen Biegepr{\"u}fstands}, series = {Virtuelle Instrumente in der Praxis 2015 - Begleitband zum 20. VIP-Kongress.}, booktitle = {Virtuelle Instrumente in der Praxis 2015 - Begleitband zum 20. VIP-Kongress.}, editor = {Rahman, Jamal and Heinze, Ronald}, publisher = {VDE-Verlag}, address = {Berlin/Offenbach}, language = {de} } @article{RomanoEisenriedJungbaueretal., author = {Romano, Marco and Eisenried, Michael and Jungbauer, Bastian and Ehrlich, Ingo and Gebbeken, Norbert}, title = {Influence of parameters of the production process on the material quality of unidirectionally reinforced prepregs}, series = {Journal of Achievements in Materials and Manufacturing Engineering (JAMME)}, volume = {68}, journal = {Journal of Achievements in Materials and Manufacturing Engineering (JAMME)}, number = {1}, pages = {32 -- 44}, abstract = {Purpose: A prepreg production device in laboratory scale is used to develop the production process of unidirectionally reinforced prepregs. Design/methodology/approach: The aim of the prepreg production device is to impregnate different types of reinforcement fibers with an arbitrarily selectable thermoset matrix system that completely satisfies the requirements for autoclave processing. As the prepreg production device is designed and built up modularly every module corresponds one step in the process. Findings: To identify the parameters of the production process and investigate its sensitivity on the material quality of both the prepreg as an uncured semi-finished product and the composite as the cured material experimental investigations regarding the resin flow, fiber volume content, mass per unit area and void content are carried out. Overall four material combinations have been investigated, where in each case the selected impregnation temperature and the width of the impregnation gap has been reproducibly varied in selected steps. Research limitations/implications: The experimental characterization of the prepregs and of the composite material is carried out according to German standards.}, language = {en} } @article{RomanoEhrlichGebbeken, author = {Romano, Marco and Ehrlich, Ingo and Gebbeken, Norbert}, title = {Parametric characterization of a mesomechanic kinematic caused by ondulation in fabric reinforced composites: analytical and numerical investigations}, series = {Frattura ed Integrit{\`a} Strutturale (Fracture and Structural Integrity)}, volume = {11}, journal = {Frattura ed Integrit{\`a} Strutturale (Fracture and Structural Integrity)}, number = {39}, doi = {10.3221/IGF-ESIS.39.22}, pages = {226 -- 247}, abstract = {A parametric characterization of a mesomechanic kinematic caused by ondulation in fabric reinforced composites is investigated by analytical and numerical investigations. Due to the definition of plain representative sequences of balanced plain-weave fabric reinforced single layers based on sines the variable geometric parameters are the amplitude and the length of the ondulation. The mesomechanic kinematic can be observed in both the analytic model and the FE-analyses. The analytic model yields hyperbolic correlations due to the strongly simplifying presumptions that neglect elasticity. In contrast the FE-analyses yield linear correlations in much smaller amounts due to the consideration of elastic parts, yet distinctly.}, language = {en} } @article{SieglEhrlich, author = {Siegl, Marco and Ehrlich, Ingo}, title = {Transformation of the Mechanical Properties of Fiber-Reinforced Plastic Tubes from the Cartesian Coordinate System into the Cylindrical Coordinate System for the Application of Bending Models}, series = {Athens Journal of Technology \& Engineering}, volume = {4}, journal = {Athens Journal of Technology \& Engineering}, number = {1}, pages = {47 -- 62}, abstract = {Fiber-reinforced plastic (FRP) tubes are used in many different industries, such as electrical engineering and pipeline construction. The tubes are frequently subjected to bending loads, depending on the application. In order that the dimensioning of the tubes can be ensured, analytical bending models are used to calculate the resulting stresses, strains and displacements in the individual layers of the laminate. This enables the making of a statement about the failure of the fiber-reinforced tube by choosing an appropriate failure criterion. For the use of these bending models, it is necessary to understand the respective underlying theory. The theory provides the basis for the mathematical description of the mechanical properties for a single-layered tube and using the relationships between the stresses and strains that occur in the Cylindrical coordinate system for this calculation step. For this reason, a redefinition of the compliance matrix from the transformation about the winding angle to the Cylindrical coordinate system and a modification of the stress and strain vectors is necessary, because the defined Cartesian coordinate system of the model cannot be used for wounded FRP tubes. The transformation causes an exchange of entries in the compliance matrix, which remain in the correct relationship between the particular stress and strains. This step is not specified and may lead to incorrect results due to the incorrect entry of compliances. The present publication refers to sketch on this issue and represent a simplification of the changeover to the level required by the bending models notation of vectors in the form of a permutation. In addition, a new name for the pre-acquisition of the redefined compliances is given to prevent confusion when entering the material law of a bending model. Finally, the permuted and redefined compliances are proved in an example to determine their accuracy.}, language = {en} } @inproceedings{PutzerPenzkoferEhrlichetal., author = {Putzer, Michael and Penzkofer, Rainer and Ehrlich, Ingo and Rasmussen, John and Gebbeken, Norbert and Dendorfer, Sebastian}, title = {Musculoskeletal simulations to investigate the influence of vertebral geometrical parameters on lumbar spine loading}, series = {7th World Congress of Biomechanics, Boston, United States, 04/07/14 -11/07/14}, booktitle = {7th World Congress of Biomechanics, Boston, United States, 04/07/14 -11/07/14}, language = {de} } @misc{JudenmannPongratzEhrlichetal., author = {Judenmann, Anna and Pongratz, Christian and Ehrlich, Ingo and H{\"o}fer, Philipp and Holtmannsp{\"o}tter, Jens}, title = {Additive Fertigung von endlosfaserverst{\"a}rkten Kunststoffstrukturen}, series = {M{\"u}nchner Leichtbauseminar 2022, 26. October 2022, 16. November 2022, 30 November 2022, Munich/Neubiberg/Garching}, journal = {M{\"u}nchner Leichtbauseminar 2022, 26. October 2022, 16. November 2022, 30 November 2022, Munich/Neubiberg/Garching}, abstract = {Additive Fertigung hat sich in zahlreichen industriellen Anwendungen etabliert und bildet eine wichtige Schl{\"u}sseltechnologie. Im Gegensatz zu metallischen Werkstoffen, haben additiv gefertigte Bauteile aus Kunststoffen geringere Festigkeit und Steifigkeit, sodass sich ihre Verwendung als lasttragende Strukturen schwierig gestaltet. Insbesondere der Einsatz von endlosen Verst{\"a}rkungsfasern kann die mechanischen Eigenschaften additiv gefertigter Strukturen signifikant verbessern und die Fertigung hochbelastbarer Faserverbundstrukturen im 3D-Druckverfahren erm{\"o}glichen. Daher gilt es aktuell notwendige Anlagen und Prozessketten f{\"u}r den Fertigungsprozess aber auch Vorgehensweisen f{\"u}r die belastungsoptimierte Auslegung der Faserverl{\"a}ufe innerhalb des Bauteils zu entwickeln, um so das Themengebiet „Endlosfaserverst{\"a}rkter 3D-Druck" weiter voranzutreiben. F{\"u}r mehr r{\"a}umliche Freiheit bei der Positionierung der Druckbahnen k{\"o}nnen industrieroboterbasierte Systeme eingesetzt werden, um so das Potenzial gerichteter Bauweise von Faserverbundstrukturen auch im additiven Fertigungsprozess vollumf{\"a}nglich aussch{\"o}pfen zu k{\"o}nnen. Dabei erm{\"o}glicht ihr Einsatz auch eine r{\"a}umliche Ablage der Faserverst{\"a}rkung, wobei f{\"u}r die Materialablage ein geeigneter 3D-Druckkopf erforderlich ist. F{\"u}r die Implementierung der Faserverst{\"a}rkung ist zudem eine dem Lastfall entsprechende Auslegung des Bauteils sowie die Ermittlung einer sinnvollen Faserpositionierung innerhalb des Bauteils erforderlich, wobei unterschiedliche Variablen aus den Bereichen Material, Struktur und Fertigungsprozess ber{\"u}cksichtigt werden m{\"u}ssen. Im Rahmen des Vortrages werden die Herausforderungen der Technologieentwicklung des endlosfaserverst{\"a}rkten 3D-Drucks aufgegriffen sowie auf eine belastungsorientierte Faserpositionierung n{\"a}her eingegangen. Aktuelle Erkenntnisse werden diskutiert sowie eine Entwurfsmethodik f{\"u}r die Prozesspfadgenerierung vorgeschlagen.}, language = {de} } @article{BodeEhrlich, author = {Bode, J. and Ehrlich, Ingo}, title = {Entwicklung eines finiten Elements f{\"u}r Sandwichanwendungen}, series = {Zeitschrift f{\"u}r Angewandte Mathematik und Mechanik (ZAMM), Journal of Applied Mathematics and Mechanics}, volume = {77}, journal = {Zeitschrift f{\"u}r Angewandte Mathematik und Mechanik (ZAMM), Journal of Applied Mathematics and Mechanics}, number = {1}, pages = {41 -- 42}, language = {de} }