TY - RPRT A1 - Hille, Carsten A1 - Morcinczyk-Meier, Daria A1 - Schneider, Sarah A1 - Mietzner, Dana T1 - From InnoMix to University–Industry Collaboration: Fostering Exchange at Eye Level N2 - In this paper, we address a specific tool—InnoMix—that is implemented to overcome the lack of university–industry interaction in a selected region facing structural change with its corresponding impact on the economy and society. InnoMix is facilitated and implemented by university-based transfer scouts who act as mediators and translators between the players of the regional innovation system. These transfer scouts are part of the Innovation Hub 13, in which the region’s partners and stakeholders, infrastructures and competencies are systematically networked with each other to set new impulses for knowledge and technology transfer. These new impulses are brought into the region through new transfer approaches ranging from people and tools to infrastructure. InnoMix can be considered to be a highly interactive tool to overcome the weak, direct interaction between researchers and potential corporate partners in the region to foster strong collaboration between academia and industry. InnoMix especially aims to strengthen interdisciplinary exchange to shed light on cross-disciplinary perspectives. For that reason, transfer scouts focusing on transfer activities related to the life sciences, digitalisation and lightweight construction are involved in the implementation of InnoMix. Based on 11 InnoMix running since 2019, we provide insights into the planning and preparation phase of InnoMix and the selection of relevant topics and requirements for matching participants. Furthermore, we clearly indicate which formats of InnoMix work best and in which way university–industry interactions could be curated after InnoMix is implemented. T3 - fast track to TRANSFER : Working Paper Series - 001 KW - collaboration KW - transfer scout KW - knowledge and technology transfer (KTT) KW - innovation KW - innovation hub KW - networking/matchmaking Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-15461 PB - Technische Hochschule Wildau ; Brandenburgische Technische Universität Cottbus-Senftenberg ER - TY - CHAP A1 - Alarcón, Daniel A1 - Schneider, Sarah A1 - Kamenzky, Robert A1 - Blaschke, Peter T1 - Across the Picket Fence: Influence of Sampling Frequency in Automatic Impact Modal Testing T2 - Special Topics in Structural Dynamics, Volume 5 : Proceedings of the 36th IMAC, A Conference and Exposition on Structural Dynamics 2018 N2 - Automatic impact modal testing is a technique gaining momentum in recent years thanks to the popularization of Scanning Laser Doppler Vibrometry. These systems allow automatizing the output measurement of thousands of degrees of freedom in a short time. The use of automatic impact modal hammers allows automatizing the excitation input and broadband excitation without loading a structure with an extra mass or other drawbacks. However, the impact force repeatability is a prominent concern among test engineers, especially those who work with materials with non-proportional force/response ratios. Assessing the impact force repeatability of a given automatic modal hammer or test rig is necessary in order to ensure the right response level is measured impact after impact. The assessment procedure can be misleading if not done right. Studying the automatic modal hammer repeatability under typical modal test conditions invariably leads to impact signals strongly distorted by the so called picket fence effect. This results in impacts sampled by only 3–4 data points; insufficient to accurately describe the actual impact force signals and the short contact times between hammer tip and structure. In the reality, the impacts are of larger magnitudes and shorter contact times than what is shown by the analyzer in typical test conditions. This work studies the influence of the sampling frequency and the test structures used on the repeatability assessment of automatic impact modal hammers. Impact force signals are acquired in this work with enough resolution to eliminate the picket fence effect and truly evaluate how repeatable and reproducible automatic impacts are. The practicality of the procedure, which involves very large datasets and long testing times, is discussed. Guidelines are offered at the end of the paper for a successful repeatability and reproducibility assessment of automatic impact modal hammers. KW - experimental modal analysis KW - sampling KW - automatic modal hammer KW - impact modal testing KW - validation Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-21515 PB - River Publishers ER - TY - CHAP A1 - Schneider, Sarah A1 - Mallareddy, Tarun Teja A1 - Alarcón, Daniel A1 - Kamenzky, Robert A1 - Blaschke, Peter T1 - Experimental Modal Analysis of Structures with Conventional Versus Contact-Free Suspension T2 - Special Topics in Structural Dynamics, Volume 5 : Proceedings of the 36th IMAC, A Conference and Exposition on Structural Dynamics 2018 N2 - The existence of free boundary conditions is frequently assumed for Experimental Modal Analysis (EMA) of a structure. However, free-free conditions can only be approximated because the structure must be supported in some manner. Therefore, comparing simulated data with experimental data can be deceiving, because these suspensions falsify modal parameters especially structural damping and stiffness. The current scenario of structural analysis is more towards focusing on modal updating or correlation, rather than the simulation results (FE) or the experimental results. So it is imperative to bridge the gap between FE and EMA, by carefully studying various parameters. To overcome these drawbacks, levitation is suggested as a truly free-free suspension method. The levitation method was developed to allow a non-destructive, adaptable, and completely contactless approach for material testing: the structure under test is suspended on a thin film of pressurized air providing an aerodynamic bearing, levitating the specimen. Two suspension devices were constructed. Pressurized air is circulated into a casing with a single outlet (“air cushion”) or a fine grid of outlets (“air bed”). A study was performed to investigate the influence of the support conditions on the modal parameters eigenfrequency and damping. Tested specimens were a brass plate, a stainless steel plate and two composite material probes. The tested suspension methods were (a) foam mat, (b) air cushion and (c) air bed. Modal tests were performed using a Scanning Laser Doppler Vibrometer (SLDV) and an automatic modal hammer for excitation. Evaluations of the measurements were performed manually. The results showed that the detected eigenfrequencies of the metallic specimen have a variation below ±0.3% for the tested suspension methods. This variation is 10 times higher for the composite plates and lies between ±3%. The damping ratios of the levitation suspensions show the different material behavior of metallic and composite specimen: damping ratios of metallic specimen lie between 0.05–0.5% whereas damping ratios of composite plates are ten times higher and lie between 0.3% and 3%. The damping ratios measured with the air cushion are smaller than the damping ratios for the air bed supporting the hypothesis that a laminar air film under the specimen leads to less additional damping. The study shows that EMA can be performed on metallic and composite specimens using contact-less suspension methods. Especially for light-weight material specimens where EMA cannot be performed or where the results are not reliable, the contact-less suspension (levitation method) can be used. KW - modal analysis KW - levitation KW - free-free suspension KW - composite material KW - automatic modal hammer Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-21533 PB - River Publishers ER - TY - CHAP A1 - Mallareddy, Tarun Teja A1 - Alarcón, Daniel A1 - Schneider, Sarah A1 - Blaschke, Peter T1 - The Influence of Geometrical Correlation in Modal Validation Using Automated 3D Metrology T2 - Rotating Machinery, Vibro-Acoustics & Laser Vibrometry, Volume 7 : Proceedings of the 36th IMAC, A Conference and Exposition on Structural Dynamics 2018 N2 - Structural analysis is a major part of all manufacturing and testing industries. The need for high level accuracy of the results in the testing field has increased progressively, resulting in development of advanced state of art techniques. In order to acquire the vibrational characteristics of a structure, a detailed Finite Element Analysis (FEA) modelling is performed. Also, Experimental Modal Analysis (EMA) is conducted to extract the dynamic characteristics of a structure. The results obtained from both the processes are correlated for validation purposes. Based on the correlation (good or bad) the structural analysis is validated. In most cases the correlation is not satisfactory; it is mainly because of the boundary conditions that differ in FE and EMA. This research study explains in detail how important the boundary conditions are for modal validation. But the most imperative part, as the first step of correlation, is the geometry analysis. If the geometrical correlation is not accurate, the later part of correlation will turn out to be an assumption based on inaccuracies. Assumption of a geometrical correlation, without being sure of the differences, will lead to inaccurate results for validation. A reference plate is tested and simulated by using EMA and FEA techniques respectively. EMA is conducted by using a 3D SLDV for measuring the output response and the input force of excitation is induced by a Scalable Automatic Modal hammer (SAM). This plate is then scanned using ATOS Triple Scan II GOM 3D geometry scanner. The scanned results are compared with the FE model of the reference plate. The results presented show the importance of geometrical correlation for modal validation and provide results of deviations that were observed on a reference plate. With these conclusions, working on modal validation can be developed by reducing the inaccuracies for the presentation of correlation. KW - experimental modal analysis KW - impact modal testing KW - validation KW - geometrical correlation KW - 3D geometry scanner KW - FE KW - non-mass loaded impact Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-21524 PB - River Publishers ER - TY - CHAP A1 - Mallareddy, Tarun Teja A1 - Schneider, Sarah A1 - Blaschke, Peter T1 - Advanced Hammer Excitation Technique for Impact Modal Testing on Lightweight Materials Using Scalable Automatic Modal Hammer T2 - Topics in Modal Analysis & Testing, Volume 9 : Proceedings of the 36th IMAC, A Conference and Exposition on Structural Dynamics 2018 N2 - Experimental Modal Analysis (EMA) on a lightweight material has proven to be very challenging in the recent past. The applications of these materials have increased invariably in various fields and so have a high demand for Research & Development (R&D). A lightweight material is very sensitive in terms of vibration. EMA on these materials in free - free boundary condition is very complicated as the hammer excitation becomes very difficult. In order to acquire valid results, the conditions are modified, and in consequence, obtain inaccurate dynamic characteristics. Some of the major challenges faced are: (a) material getting displaced from its original position after every hit, (b) difficulties in obtaining a single hit, (c) reproducing the same excitation force level for averaging output response. Overcoming these crucial challenges can result in reducing the inaccuracies in the results. Scalable Automatic Modal hammer (SAM) is developed to overcome these challenges and enables the ability to reproduce the same force level of excitation. This advanced hammer excitation technique has the capability to avoid the double hit, adjust the repeatability of force level and automatizes the entire excitation process. In this research paper, a light weight material is experimented under free-free boundary condition and the obtained results are analyzed. The input hammer excitation is provided by SAM and the output contactless response is measured by Scanning Laser Doppler Vibrometer (SLDV). The conclusions provided will reflect the importance of repeatability and reproducibility of hammer excitation force level in order to acquire accurate results. The controlling of SAM, by changing various parameters, in order to precisely excite lightweight structures will be demonstrated. KW - experimental modal analysis KW - impact modal testing KW - lightweight material testing KW - non-mass-loaded impact KW - validation Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-21508 PB - River Publishers ER -