TY - JOUR A1 - Neumann, Patrick P. A1 - Hirschberger, Paul A1 - Bartholmai, Matthias ED - Zemčík, R. ED - Krystek, J. T1 - Influence of rotor downwash on vertically displaced nanobots in flight N2 - One challenge associated with navigating a nano aerial robot swarm indoors in unstructured environments is, i.a., the limited air space. To avoid an over-regulation of the available indoor air space (e.g., prohibit copters to fly above each other), a safety region around each copter must be defined. In this paper, we investigate the impact of the downwash of a nano-drone on the stability of another nearby nano-drone. In the experiments, we found out that this downwash has a negative influence of a second nano-drone in a distance of around 1 m vertically and 0.2 m horizontally. Based on the obtained data, we developed a model describing the above-mentioned safety region to enable a safe operation of the swarm in these environments with fewer constraints. T2 - 36th Danubia-Adria Symposium on Advances in Experimental Mechanics CY - Pilsen, Czech Republic DA - 24.09.2019 KW - Mobile Robot Olfaction KW - Nano aerial robot KW - Swarm KW - Collision-free navigation KW - Safety region model PY - 2020 DO - https://doi.org/10.1016/j.matpr.2020.03.047 VL - 32 IS - 2 SP - 108 EP - 111 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-50673 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Bartholmai, Matthias T1 - Real-time wind estimation on a micro unmanned aerial vehicle using its inertial measurement unit N2 - This paper presents an approach for a quadrocoper-based micro unmanned aerial vehicle (UAV) that estimates the wind vector (speed and direction) in real-time based on measurement data of its on-board sensors only. This method does not need any additional airspeed sensor or dedicated anemometer, and thus the micro UAV's valuable payload remains free for other sensors. Wind tunnel and field tests were used to evaluate the performance of the approach. In order to quantify its accuracy, experiments are presented where data was collected with an anemometer placed in an open field with the micro UAV in flight following a predefined trajectory around the anemometer and hovering at a defined position close to it. KW - Micro unmanned aerial vehicle (UAV) KW - Quadrocopter KW - Real-time KW - Inertial measurement unit (IMU) KW - Airspeed calibration KW - Wind estimation (speed and direction) PY - 2015 DO - https://doi.org/10.1016/j.sna.2015.09.036 SN - 0924-4247 VL - 235 SP - 300 EP - 310 PB - Elsevier Science CY - Amsterdam [u.a.] AN - OPUS4-34737 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bartholmai, Matthias A1 - Kammermeier, Michael A1 - Koeppe, Tabea A1 - Werner, Klaus-Dieter ED - Nicoletto, G. ED - Pastrama, S.D. ED - Emri, I. T1 - High dynamic measurement of strain and acceleration using a multichannel measuring system with single cable serial connection N2 - Strain and acceleration measurement during high dynamic drop tests, e.g., of containments for dangerous goods is performed using high speed multichannel measuring systems. So far established and operated systems need a cable connection of every strain gauge and acceleration sensor with the measuring device, often counting up to a number of more than 100 cables, corresponding to the number of applied sensors. The result is a massive cable harness consisting of all single cables, which is difficult to handle and causes a number of practical problems. An innovative approach is proposed by using a single cable measuring system, consisting of measuring modules with data bus connection and local data acquisition. Promising results were presented in a previous study. This paper follows up with additional results from full-scale testing of a further enhanced single cable system for the application in drop tests. T2 - 32nd DANUBIA ADRIA SYMPOSIUM on Advances in Experimental Mechanics CY - Starý Smokovec, Slovakia DA - 22.09.2015 KW - Multichannel measuring KW - Single cable serial connection KW - Dangerous goods container KW - Drop test KW - High impact testing PY - 2016 DO - https://doi.org/10.1016/j.matpr.2016.03.023 SN - 2214-7853 VL - 3 IS - 4 SP - 931 EP - 935 PB - Elsevier Ltd. AN - OPUS4-35689 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Petrov, Sergej A1 - Neumann, Patrick P. A1 - Werner, Klaus-Dieter A1 - Wosniok, Aleksander A1 - Lazik, D. A1 - Bartholmai, Matthias ED - Nicoletto, G. ED - Pastrama, S.D. ED - Emri, I. T1 - Concept for investigating mechanical and thermal impacts on distributed subsurface gas monitoring N2 - A multifunctional sensor in line shape was developed and introduced in previous work for measuring of gas concentrations, temperature change, and strain. A current field study focuses on a spatially distributed monitoring of subsurface CO 2 gas storage sites in near real time. Mechanical impacts, e.g., caused by construction work, denudation, and seismic activity, can affect the integrity of underground gas storage sites. Thermal or moisture impacts, e.g., caused by weather conditions, can influence the gas Distribution behavior. In this paper, we briefly describe the setup of a CO 2 injection soil test field. This setup contains actuating elements for the investigation of mechanical and thermal impacts on distributed subsurface gas monitoring. A concept is given for evaluating these impacts and first experimental results are presented. T2 - 32nd DANUBIA ADRIA SYMPOSIUM on Advances in Experimental Mechanics CY - Starý Smokovec, Slovakia DA - 22.09.2015 KW - Linear sensor KW - Distributed sensor KW - Monitoring of CO 2 KW - Subsurface monitoring KW - Gas storage areas KW - Membrane-based gas sensing KW - Fibre optical sensing PY - 2016 DO - https://doi.org/10.1016/j.matpr.2016.03.060 SN - 2214-7853 VL - 3 IS - 4 SP - 1124 EP - 1128 PB - Elsevier Ltd. AN - OPUS4-35688 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Ebert, S. A1 - Lazik, D. A1 - Bartholmai, Matthias ED - Nicoletto, G. ED - Dan Pastrama, S. ED - Emri, I. T1 - Inverse calibration routine for linear soil gas sensors N2 - Gas sensors in linear form based on the measuring principle of gas selective permeability through a membrane were developed and introduced for the detection and quantification of gas concentrations. A current field study focuses on measuring CO2 concentrations for a spatially distributed monitoring of subsurface CO2 gas storage sites in near real time. A 400 m² test site and a corresponding laboratory system were built up to characterize, validate, and optimize the sensor. A calibration routine was developed, which can be applied subsequently to underground installation. First measurement results indicate the potential of the method. T2 - 32nd Danubia Adria Symposium on Advances in Experimental Mechanics CY - Starý Smokovec, Slovakia DA - 22.09.2015 KW - Linear sensor KW - Distributed sensor KW - Subsurface monitoring KW - Gas storage areas KW - Membrane-based gas sensing KW - Calibration PY - 2016 UR - http://www.sciencedirect.com/science/article/pii/S221478531600256X DO - https://doi.org/doi:10.1016/j.matpr.2016.03.051 SN - 2214-7853 VL - 3 IS - 4 SP - 1074 EP - 1078 PB - Elsevier Ltd. AN - OPUS4-35633 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Lazik, D. A1 - Bartholmai, Matthias T1 - Tomographic reconstruction of soil gas distribution from multiple gas sources based on sparse sampling N2 - A monitoring method is introduced that creates twodimensional (2D) maps of the soil gas distribution. The method combines linear gas sensing technology for in-situ monitoring of gases in soil with the mapping capabilities of Computed Tomography (CT) to reconstruct spatial and temporal resolved gas distribution maps. A weighted iterative algebraic reconstruction method based on Maximum Likelihood with Expectation Maximization (MLEM) in combination with a source-by-source reconstruction approach is introduced that works with a sparse setup of orthogonally-aligned linear gas sensors. The reconstruction method successfully reduces artifact production, especially when multiple gas sources are present, allowing the discrimination between true and non-existing so-called ghost source locations. Experimental validation by controlled field experiments indicates the high potential of the proposed method for rapid gas leak localization and quantification with respect to Pipeline or underground gas storage issues. KW - Computed tomography KW - Gas distribution mapping and gas source localization KW - Discrimination of multiple gas sources KW - Distributed linear sensor KW - Membrane-based gas sensing KW - Subsurface monitoring KW - Gas storage areas PY - 2016 DO - https://doi.org/10.1109/JSEN.2016.2545103 SN - 1530-437X VL - 16 IS - 11 SP - 4501 EP - 4508 PB - IEEE - Inst. Electrical Electronics Engineers Inc CY - Hoes Lane, NJ, USA AN - OPUS4-36228 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lazik, D. A1 - Ebert, S. A1 - Neumann, Patrick P. A1 - Bartholmai, Matthias T1 - Characteristic length measurement of a subsurface gas anomaly - A monitoring approach for heterogeneous flow path distributions N2 - Geogenic gases from natural sources, carbon dioxide (CO2) from a geological repository (carbon capture and storage - CCS) or a leaking gas pipeline can present serious risks in industrial and urban areas. To extend the lead time for risk treatment in such critical regions, reliable detection of gases within the shallow subsurface is required to observe critical gas accumulations before degassing into the atmosphere. A near real-time monitoring approach is introduced to determine the volumetric expansion of a leakinggas in the subsurface. Considering the pressure relaxation with the ambient air pressure, the approach enables the forecasting of the final size of a pressurized gas body in terms of characteristic lengths. According to theoretical basics, such a characteristic length, which enables us to perform a gas (safety) measurement based on a purely geometrical measure, behaves independently of subsurface properties,i.e., it enables a reliable quantification of the escaping gas irrespective of its heterogeneous or changingflow path distribution. A field test for a 10 l/min pinhole leakage injected into a 10 m long, 0.4 m wide, 0.95 m deep soil-filled trench that was equipped with linear sensors shows the lateral-vertical volumetric gas expansion along these sensors, and demonstrates the applicability of the characteristic length approach. KW - Monitoring KW - Carbon capture and storage KW - Leakage KW - Quantification KW - Subsurface KW - CO2 PY - 2016 DO - https://doi.org/10.1016/j.ijggc.2016.02.008 SN - 1750-5836 VL - 2016 IS - 47 SP - 330 EP - 341 PB - Elsevier B.V. AN - OPUS4-35425 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ullner, Christian A1 - Subaric-Leitis, Andreas A1 - Bartholmai, Matthias T1 - Uncertainty of Elastoplastic Material Parameters Calculated from the Spherical Indentation in the Macro Range N2 - The applicability of three methods developed by finite element analysis (FEM) and proposed in the literature are studied on steel S355. Instrumented indentation tests using spherical indenters of radius 200 and 500 μ m are performed in the macro range at depths of more than 6 μ m. The results of the selected methods are compared with the tensile test. To evaluate the partially strongly varying results, the uncertainties of the calculated strain hardening exponent, n, and yield stress, Y, are estimated. Recommendations for an appropriated procedure of the indentation test are given. The machine compliance and the determination of the zero point of Depth play an essential role. If the certain conditions are considered, the instrumented indentation Tests can be used, in particular for investigations of specimens with inhomogeneous elastoplasticity. KW - Indentation KW - Elastoplastic material parameters KW - Uncertainty PY - 2021 DO - https://doi.org/10.1520/JTE20200683 SN - 0090-3973 VL - 49 IS - 6 SP - 4576 EP - 4592 PB - ASTM International AN - OPUS4-52416 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Hirschberger, Paul A1 - Bartholmai, Matthias ED - Holl, H. T1 - Flying ant robot for chemical trail detection and localization N2 - This paper presents first advances in the area of aerial chemical trail following. For that purpose, we equipped a palm-size aerial robot, based on the Crazyflie 2.0 quadrocopter, with a small lightweight metal oxide gas sensor for measuring evaporated ethanol from chemical trails. To detect and localize a 5 cm wide chemical trail, a detection criterion was developed that uses only relative changes in the transient phase of the sensor response. The reduction in signal strength dependence improves the robustness of its application. We tested our setup in first crossing-trail experiments showing that our flying ant robot can correlate an odor hit with the chemical trail within 0.14 m. Principally, this could enable aerial chemical trail following in the future. T2 - 37th Danubia - Adria Symposium on Advances in Experimental Mechanics CY - Linz, Austria DA - 21.09.2021 KW - Aerial robot KW - Trail following KW - Trail detection KW - Localization PY - 2022 DO - https://doi.org/10.1016/j.matpr.2022.02.594 SN - 2214-7853 VL - 62 SP - 2462 EP - 2465 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-54507 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Werner, Klaus-Dieter A1 - Petrov, Sergej A1 - Bartholmai, Matthias A1 - Lazik, D. ED - Puente León, F. ED - Zagar, B. T1 - Aufbau eines großflächigen Testfeldes für verteilte Bodengassensorik und Untersuchung einer Monitoringmethode basierend auf Tomographie T1 - Setup of a large-scale test field for distributed soil gas sensors and testing of a monitoring method based on tomography N2 - A 400 m² soil test field with gas injection system was built up for the purpose of large-scale validation, optimization, and characterization of a novel comprehensive monitoring method for underground gas storage areas. The method combines gas sensing technology with linear form factor for in-situ monitoring of gases in soil with the mapping capabilities of Computed Tomography (CT) to reconstruct time-series of gas distribution maps based on samples of orthogonally-aligned linear gas sensors. Several injection experiments with carbon dioxide (CO2) at different days with varying boundary conditions indicates the potential of the method for, e.g., rapid leakage detection with respect to Carbon Capture and Storage (CCS) issues. N2 - Zur Validierung, Optimierung und praxisnahen Demonstration eines flächendeckenden Monitoringverfahrens für Untergrundgasspeichern wurde ein 400 m² großes Testfeld mit Gasinjektionssystem auf dem BAM Testgelände Technische Sicherheit aufgebaut. Die Methode kombiniert verteilte, linienförmige Gassensorik für die In-situ-Überwachung von Gasen im Boden mit den Mapping-Fähigkeiten der Computertomographie (CT). Auf Basis von orthogonal zueinander ausgerichteten linearen Gassensoren können mit diesem Verfahren so Zeitreihen der Gasverteilung rekonstruiert werden. Experimente mit Kohlendioxid (CO2) zeigen das Potential des Verfahrens zur schnellen Lokalisierung von Leckagen auf. KW - Soil test field KW - Distributed linear sensor KW - Membrane-based gas sensing KW - Subsurface monitoring KW - Gas storage areas KW - Computed tomography PY - 2016 DO - https://doi.org/10.1515/teme-2016-0015 SN - 2196-7113 SN - 0171-8096 VL - 83 IS - 10 SP - 606 EP - 615 PB - Walter de Gruyter GmbH CY - Berlin, Deutschland AN - OPUS4-37653 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -