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 - Köppe, Enrico A1 - Bartholmai, Matthias A1 - Daum, Werner A1 - Gong, Xing A1 - Hofmann, Detlef A1 - Basedau, Frank A1 - Schukar, Vivien A1 - Westphal, Anja A1 - Sahre, Mario A1 - Beck, Uwe T1 - New self - diagnostic fiber optical sensor technique for structural health monitoring N2 - Fiber optic sensors have gained increasing importance in recent years and are well established in many areas of industrial applications. In this paper, we introduce a concept of a self-diagnostic fiber optic sensor. The presented sensor is to resolve the problems of embedded fiber optic sensors in complex structures and to enable the validation under operational conditions. For this purpose, different magnetostrictive coated fiber optic sensors were developed and various experiments were performed to verify their mode of Operation and to determine the respective reproducibility. The measuring principle is illustrated by obtained experimental results, which showed a change in wavelength from 1 pm at a magnetic field strength change of 0.25 mT. In addition, the temperature characteristics of the implemented magnetostrictive sensor were analyzed and an experimental factor of 1.5 compared to a reference fiber optic sensor was determined. T2 - 32nd DANUBIA ADRIA SYMPOSIUM on Advances in Experimental Mechanics CY - Starý Smokovec, Slovakia DA - 22.09.2015 KW - Self-diagnostic fiber optical sensor KW - Magnetostrictive metal coating KW - Magnetic field KW - Fiber bragg grating PY - 2016 DO - https://doi.org/10.1016/j.matpr.2016.03.038 SN - 2214-7853 VL - 3 IS - 4 SP - 1009 EP - 1013 AN - OPUS4-37131 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 - CONF A1 - Bartholmai, Matthias A1 - Neumann, Patrick P. A1 - Werner, Klaus-Dieter A1 - Ebert, Sebastian A1 - Lazik, D. T1 - Linear sensor for areal subsurface gas monitoring - calibration routine and validation experiments N2 - Membrane based linear gas sensors and fiber optical sensors feature similar geometries and complement each other in quantities to be measured. To the author's best knowledge, it is the first time that these sensors are combined to a multifunctional sensor for distributed measuring of gas concentrations, temperature, and strain. Objective is a comprehensive monitoring of underground gas storage areas. In the presented project a 400 m² test site and a corresponding laboratory system were just built up to characterize, validate, and optimize the combined sensor. Application of the sensor lines in a grid structure should enable spatial resolution of the measurement data and early detection of relevant events, as gas leakage, temperature change, or mechanical impact. A Calibration routine was developed which can be applied subsequent to underground installation. First measurement results indicate the potential of the method, with regard to highly topical energy transport and storage issues. T2 - IEEE Sensors 2014 conference CY - Valencia, Spain DA - 02.11.2014 KW - Linear sensor KW - Distributed sensor KW - Monitoring of CO2 KW - Subsurface monitoring KW - Gas storage areas KW - Membrane-based gas sensing KW - Fibre optical sensing PY - 2014 SN - 978-1-4799-0161-6 DO - https://doi.org/10.1109/ICSENS.2014.6985157 SP - 942 EP - 945 AN - OPUS4-32083 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Schnürmacher, M. A1 - Bennetts, V.H. A1 - Lilienthal, A.J. A1 - Bartholmai, Matthias A1 - Schiller, J.H. T1 - A probabilistic gas patch path prediction approach for airborne gas source localization in non-uniform wind fields N2 - In this paper, we show that a micro unmanned aerial vehicle (UAV) equipped with commercially available gas sensors can address environmental monitoring and gas source localization (GSL) tasks. To account for the challenges of gas sensing under real-world conditions, we present a probabilistic approach to GSL that is based on a particle filter (PF). Simulation and real-world experiments demonstrate the suitability of this algorithm for micro UAV platforms. KW - Autonomous micro UAV KW - Chemical and wind sensing KW - Gas source localization KW - Particle filter PY - 2014 DO - https://doi.org/10.1166/sl.2014.3168 SN - 1546-198X SN - 1546-1971 VL - 12 IS - 6/7 SP - 1113 EP - 1118 PB - American Scientific Publishers (ASP) CY - Stevenson Ranch, CA, USA AN - OPUS4-31525 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Bennetts, V.H. A1 - Lilienthal, A.J. A1 - Bartholmai, Matthias T1 - From insects to micro air vehicles - a comparison of reactive plume tracking strategies N2 - Insect behavior is a common source of inspiration for roboticists and computer scientists when designing gas-sensitive mobile robots. More specifically, tracking airborne odor plumes, and localization of distant gas sources are abilities that suit practical applications such as leak localization and emission monitoring. Gas sensing with mobile robots has been mostly addressed with ground-based platforms and under simplified conditions and thus, there exist a significant gap between the outstanding insect abilities and state-of-the-art robotics systems. As a step toward practical applications, we evaluated the performance of three biologically inspired plume tracking algorithms. The evaluation is carried out not only with computer simulations, but also with real-world experiments in which, a quadrocopter-based micro Unmanned Aerial Vehicle autonomously follows a methane trail toward the emitting source. Compared to ground robots, micro UAVs bring several advantages such as their superior steering capabilities and fewer mobility restrictions in complex terrains. The experimental evaluation shows that, under certain environmental conditions, insect like behavior in gas-sensitive UAVs is feasible in real-world environments. T2 - IAS13 - 13th International conference on intelligent autonomous systems CY - Padova, Italy DA - 2014-07-15 KW - Autonomous micro UAV KW - Mobile robot olfaction KW - Gas source localization KW - Reactive plume tracking KW - Biologically inspired robots PY - 2016 SN - 978-3-319-08338-4; 978-3-319-08337-7 DO - https://doi.org/10.1007/978-3-319-08338-4_110 SN - 2194-5357 SP - 1533 EP - 1548 PB - Springer Verlag CY - Berlin, Germany AN - OPUS4-31526 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Kohlhoff, Harald A1 - Werner, Klaus-Dieter A1 - Erdmann, Jessica A1 - Eggeringhaus, Bärbel A1 - Kammermeier, Michael A1 - Schukar, Marcus A1 - Basedau, Frank A1 - Bartholmai, Matthias A1 - Lazik, D. A1 - Ebert, Sebastian T1 - Setup of a large scale soil test field with CO2 injection for testing a novel distributed subsurface monitoring system for gas storage areas N2 - One of the main unsolved issues of under-ground storages for, e.g., CO2, H2, and natural gas is the comprehensive surveillance of these areas with reasonable effort and costs. Conventional sensors (e.g., soil air probes or borehole probes), however, can only be used for punctual or locally limited measurements; further their application can cause structural influences (invasive application). In this paper, we describe in detail the setup of a CO2 injection soil test field. This test field will be used to enhance and validate an innovative ap-proach for distributed subsurface monitoring of gas storage areas. To the author’s knowledge, this is the first time that, for this purpose, a test field is built in an application relevant scale. T2 - 31st Danubia-Adria Symposium on advances in experimental mechanics CY - Kempten, Germany DA - 24.09.2014 KW - Large scale soil test field KW - Subsurface monitoring KW - Gas storage areas KW - Membrane-based gas sensing KW - Fiber optical sensing PY - 2014 SN - 978-3-00-046740-0 SP - 238 EP - 239 AN - OPUS4-31527 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Werner, Klaus-Dieter A1 - Kammermeier, Michael T1 - Hopkinson bar method for temperature dependent testing and calibration of accelerometers N2 - The measurement characteristics of every conventional accelerometer are temperature dependent - often to an extent which is highly relevant for the addressed application. For instance, at BAM Container drop tests are performed to investigate and evaluate the structural integrity of Containers for transport and storage of dangerous goods. Often, the test program includes drop tests at specific temperatures, also as part of approval procedures. The applied sensors are exposed to these test conditions and get influenced by them. Acceleration sensors show a considerable temperature influence on their fünction and characteristics. Particularly the damping mechanism of the seismic mass is a critical part. In regard to such applications, capable equipment and methods are required to consider and investigate this aspect in an adequate way. A fortiori as Manufacturer’s infonnation often is deficient. This study presents the setup and results of a method for testing and calibration of acceleration sensors under high dynamic irnpact. It combines a Hopkinson Bar with a temperature chamber. T2 - 31st Danubia-Adria Symposium on advances in experimental mechanics CY - Kempten, Germany DA - 24.09.2014 PY - 2014 SN - 978-3-00-046740-0 SP - 244 EP - 245 AN - OPUS4-31731 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bartholmai, Matthias A1 - Werner, Klaus-Dieter A1 - Kammermeier, Michael A1 - Köppe, Enrico T1 - Erprobung eines Messsystems mit Datenbus und dezentraler Datenspeicherung für den Einsatz bei Fallprüfungen N2 - Zur Untersuchung der Sicherheit von Behältern für den Transport und die Lagerung von Gefahrstoffen und -gütern werden Fallprüfungen durchgeführt. Die Aufpralldynamik und die strukturmechanischen Einwirkungen auf den Behälter werden mittels Beschleunigungsaufnehmern und Dehnungsmessstreifen erfasst. Dabei kommen derzeit Vielkanalmesssysteme zum Einsatz, die eine Verkabelung jeder einzelnen Messstelle und somit das Mitfallen eines Kabelbaums erfordern, wodurch Probleme bei der Versuchsvorbereitung und Durchführung entstehen. Die Verwendung eines Messsystems mit Datenbus und dezentraler Datenspeicherung bietet diesbezüglich einen vielversprechenden Lösungsansatz. KW - Vielkanalmesssystem KW - Datenbus KW - Gefahrstoffe KW - Behälter KW - Fallprüfung KW - Hopkinsonstab KW - Multichannel measuring system KW - Data bus KW - Dangerous goods KW - Container KW - Drop test KW - Hopkinson bar PY - 2009 DO - https://doi.org/10.1524/teme.2009.0945 SN - 0340-837X SN - 0178-2312 SN - 0171-8096 VL - 76 IS - 10 SP - 447 EP - 454 PB - Oldenbourg CY - München AN - OPUS4-20284 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Lazik, D. A1 - Bartholmai, Matthias T1 - Leak detection with linear soil gas sensors under field conditions - First experiences running a new measurement technique N2 - A 400 m² soil test field with gas injection system was built up, which enables an experimental validation of linear gas sensors for specific applications and gases in an application-relevant scale. Several injection and soil watering experiments with carbon dioxide (CO2) at different days with varying boundary conditions were performed indicating the potential of the method for, e.g., rapid leakage detection with respect to Carbon Capture and Storage (CCS) issues. T2 - IEEE Sensors 2016 CY - Orlando, FL, USA DA - 30.10.2016 KW - Soil test field KW - Membrane-based linear gas sensor KW - Leak detection KW - Field conditions PY - 2016 SN - 978-1-4799-8287-5 SN - 1930-0395 SP - B-3-65, 757 EP - 759 PB - IEEE AN - OPUS4-38244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -