TY - CONF A1 - Bartelmeß, Jürgen A1 - Gawlitza, Kornelia A1 - Bartholmai, Matthias A1 - Rurack, Knut A1 - Kohlhoff, Harald A1 - Kraus, Werner A1 - Mansurova, Maria A1 - Bell, Jérémy T1 - Developments towards the fluorescence based sensing of hazardous gases N2 - Fluorescence based sensing is a versatile approach for the trace analysis outside of the laboratory, requiring suitable sensor materials and their integration into sensing devices. The versatility of fluorophores as probes, especially in terms of the possibility to tailor their optical as well as their recognition properties by synthetic modifications in a wide range, renders them a superior active component for the preparation of optical sensor devices. Recent works at BAM in this field include, for example, the detection of nerve gas agents, illustrating impressively the aforementioned benefits of fluorophores in optical sensing applications. In the interdisciplinary approach presented here, we target hazardous gases such as ammonia, benzene, and hydrogen sulfide, next to others, which pose a major threat to human health and environmental safety and for which the availability of a sensitive and reliable detection method is highly desirable. The dyes presented follow a “turn-on” fluorescence schematic which allows for the selective and sensitive detection of the respective gaseous analyte. The immobilization of the probe in polymeric matrices is then the next step toward the fabrication of a prototype device for molecular sensing. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - Gas sensing KW - Fluorescence KW - KonSens PY - 2017 AN - OPUS4-43209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Neumann, Patrick P. A1 - Johann, Sergej A1 - Tiebe, Carlo A1 - Gawlitza, Kornelia A1 - Bartelmeß, Jürgen T1 - KonSens - Kommunizierende Sensorsysteme für die Bauteil- und Umweltüberwachung N2 - In the KonSens Project, sensor systems are developed, validated, and operated in form of functional models for the application areas Structure Integrated Sensors and Mobile Multi-gas Sensors. Key aspects are the detection and evaluation of corrosion processes in reinforced concrete structures as well as the detection and quantification of very low concentrations of toxic gases in air. The adaption of sensor principles from the lab into real-life application including appropriate communication techniques is a major task. In recent years, Structural Health Monitoring have gained in importance, since growing age of buildings and infrastructure as well as increasing load requirements demand for reliable surveillance methods. In this regard, the project follows two strategies: First, the development and implementation of completely embedded sensor systems consisting of RFID-tag and in situ sensors, and their further application potential (e.g. for precast concrete elements, roadways, wind power plants, and maritime structures). Secondly, the development of a long-term stable, miniaturized, fiber optic sensor for a ratiometric and referenced measurement of the pH-value in concrete based on fluorescence detection as an indicator for carbonation and corrosion. Environmental pollution through emission of toxic gases becomes an increasing problem not only in agriculture (e.g. biogas plants) and industry but also in urban areas. This leads to increasing demand to monitor environmental emissions as well as ambient air and industrial air components in many scenarios and in even lower concentrations than nowadays. The selectivity of luminescence-based sensors is enabled by the combination of the sensing dye and the material, which is used as accumulation medium for concentration of the analyte. This principle allows for developing gas sensors with high selectivity and sensitivity of defined substances. Additional benefits, particularly of fluorescence-based sensors, are their capability for miniaturization and potential multiplex mode. Objective is the development and implementation of sensors based on fluorescence detection for defined toxic gases (ammonia, hydrogen sulfide, ozone, and benzene) with sensitivity in the low ppm or even ppb range. Additionally, the integration of such sensors in mobile sensor devices is addressed. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - RFID sensors KW - Sensors in concrete KW - Gas sensors KW - Mobile sensors KW - Fluorescence sensors PY - 2017 AN - OPUS4-43183 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüllmann, Dino A1 - Neumann, Patrick P. A1 - Bartholmai, Matthias T1 - Wind Vector Estimation on Multirotor Aircraft N2 - Small unmanned aircraft (UA) are used increasingly as flying sensor platforms. Amongst other things they are used for environmental monitoring, for example gas distribution mapping. Sometimes, these applications require knowledge of the ambient wind field, which can be measured by additional devices like anemometers. In general, it would be interesting to avoid such additional apparatuses. One way to achieve this is to estimate the wind vector, that is both the wind direction and speed, from the state variables of the UA. T2 - IEEE Sensors 2018 CY - New Delhi, India DA - 28.10.2018 KW - UAV KW - Wind vector KW - Estimation KW - Multirotor aircraft PY - 2018 AN - OPUS4-46479 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Werner, Klaus-Dieter T1 - Comparison of the Temperature Behavior of Oil and Gas Damped Piezoresistive Accelerometers N2 - This study presents the characterization of a piezoresistive accelerometer damped with silicon oil for the application in drop tests carried out at BAM. Experiments were performed with the Hopkinson Bar method in close correlation to the real-world application conditions. The results point out certain limitations regarding the temperature influence and the frequency response. Additional experiments were performed with a gas damped type of piezoresistive accelerometer, which has superior specifications, particularly for low temperatures. The results allow for a comparison. T2 - IEEE SENSORS 2018 CY - Neu Delhi, Indien DA - 28.10.2018 KW - Accelerometer KW - Temperature behavior KW - Frequency response KW - Hopkinson Bar KW - Drop test PY - 2018 AN - OPUS4-46484 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej A1 - Bartholmai, Matthias A1 - Werner, Klaus-Dieter A1 - Daum, Werner T1 - Characterization of the temperature behavior of a piezoresistive accelerometer N2 - Piezoresistive accelerometers use a strainsensing element, generally made of semiconductor material, e.g., silicon to convert the mechanical motion into an electrical signal. This element is usually designed in form of a cantilever beam loaded with a mass. Acceleration causes bending of the beam, which produces a change of electrical resistance proportional to the applied acceleration. Main advantages of piezoresistive accelerometers in comparison to other types, e.g., piezoelectric and capacitive, is their robust and highly dynamic behavior, which qualifies them for application in high impact shock applications. Mechanical damping is typically implemented with silicon oil in a way that the output signal is undistorted over a wide frequency range. These characteristics principally qualify them for the application in drop tests carried out at BAM, for which they are calibrated over the frequency range from 1 to 4 kHz. However, using silicon oil for damping, has the drawback of temperature dependent change of its viscosity, leading to temperature dependent deviation of the accelerometer’s sensitivity. This study presents experimental results of the temperature behavior of a piezoresistive accelerometer with a dynamic range up to ±5000 g. This type of accelerometer is applied for drop tests which are partially performed at temperatures of -40 or +100 °C. T2 - 34th Danubia-Adria Symposium on Advances in Experimental Mechanics CY - Trieste, Italy DA - 19.09.2017 KW - Piezoresistive accelerometers KW - Temperature behavior of a piezoresistive accelerometer KW - Hopkinson bar KW - Drop tests PY - 2017 AN - OPUS4-42095 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Bartholmai, Matthias A1 - Hüllmann, Dino T1 - Concept of a gas-sensitive nano aerial robot swarm for indoor air quality monitoring N2 - In industrial environments, airborne by-products such as dust and (toxic) gases, constitute a major risk for the worker’s health. Major changes in automated processes in the industry lead to an increasing demand for solutions in air quality management. Thus, occupational health experts are highly interested in precise dust and gas distribution models for working environments. For practical and economic reasons, high-quality, costly measurements are often available for short time-intervals only. Therefore, current monitoring procedures are carried out sparsely, both in time and space, i.e., measurement data are collected in single day campaigns at selected locations only. Real-time knowledge of contaminant distributions inside the working environment would also provide means for better and more economic control of air impurities. For example, the possibility to regulate the workspace’s ventilation exhaust locations can reduce the concentration of airborne contaminants by 50%. To improve the occupational health and safety of (industrial) workplaces, this work aims for developing a swarm of gas-sensitive aerial nano robots for monitoring indoor air quality and for localizing potential emission sources. T2 - Tag der offenen Tür auf dem Testgelände der BAM (BAM TTS) CY - Baruth/Mark - OT Horstwalde, Germany DA - 29.09.2018 KW - Mobile Robot Olfaction KW - Swarm KW - Nano aerial robot KW - Gas sensing PY - 2018 AN - OPUS4-46147 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Bartholmai, Matthias A1 - Hüllmann, Dino A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Kohlhoff, Harald A1 - Lilienthal, A. J. T1 - Airborne Remote Gas Sensing and Mapping N2 - Leaking methane (CH4) from infrastructures, such as pipelines and landfills, is critical for the environment but can also pose a safety risk. To enable a fast detection and localization of These kind of leaks, we developed a novel robotic platform for aerial remote gas sensing - the so-called Unmanned Aerial Vehicle for Remote Gas Sensing (UAV-REGAS). T2 - Tag der offenen Tür auf dem Testgelände der BAM (BAM TTS) CY - Baruth/Mark - OT Horstwalde, Germany DA - 29.09.2018 KW - Localization of gas sources KW - Mobile Robot Olfaction KW - Tomographic reconstruction of gas plumes KW - Tunable Diode Laser Absorption Spectroscopy (TDLAS) KW - UAV-REGAS PY - 2018 AN - OPUS4-46152 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Hüllmann, Dino A1 - Bartholmai, Matthias A1 - Tiebe, Carlo T1 - Concept of a gas-sensitive nano aerial robot swarm for indoor air quality monitoring N2 - In industrial environments, airborne by-products such as dust and (toxic) gases, constitute a major risk for the worker’s health. Major changes in automated processes in the industry lead to an increasing demand for solutions in air quality management. Thus, occupational health experts are highly interested in precise dust and gas distribution models for working environments. For practical and economic reasons, high-quality, costly measurements are often available for short time-intervals only. Therefore, current monitoring procedures are carried out sparsely, both in time and space, i.e., measurement data are collected in single day campaigns at selected locations only. Real-time knowledge of contaminant distributions inside the working environment would also provide means for better and more economic control of air impurities. For example, the possibility to regulate the workspace’s ventilation exhaust locations can reduce the concentration of airborne contaminants by 50%. To improve the occupational health and safety of (industrial) workplaces, this work aims for developing a swarm of gas-sensitive aerial nano robots for monitoring indoor air quality and for localizing potential emission sources. T2 - NetMon International training course - Low-cost Environmental Monitoring CY - BAM, Berlin, Germany DA - 09.04.2019 KW - Gas sensing KW - Mobile Robot Olfaction KW - Nano aerial robot KW - Swarm PY - 2019 AN - OPUS4-47799 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Hüllmann, Dino A1 - Bartholmai, Matthias A1 - Tiebe, Carlo A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Kohlhoff, Harald A1 - Lilienthal, A. J. T1 - Gas Tomography Up In The Air! N2 - In this paper, we present an autonomous aerial robot to reconstruct tomographic 2D slices of gas plumes in outdoor environments. Our platform, the so-called Unmanned Aerial Vehicle for Remote Gas Sensing (UAV-REGAS) combines a lightweight Tunable Diode Laser Absorption Spectroscopy (TDLAS) sensor with a 3-axis aerial stabilization gimbal for aiming on a versatile octocopter. The TDLAS sensor provides integral gas concentration measurements but no information regarding the distance traveled by the laser diode's beam or the distribution of the gas along the optical path. We complemented the set-up with a laser rangefinder and apply principles of Computed Tomography (CT) to create a model of the spatial gas distribution from these integral concentration measurements. To allow for a rudimentary ground truth evaluation of the applied gas tomography algorithm, we set up a unique outdoor test environment based on two 3D ultrasonic anemometers and a distributed array of 10 infrared gas transmitters. We present first results showing the 2D plume reconstruction capabilities of the system under realistic conditions. T2 - NetMon International training course - Low-cost Environmental Monitoring CY - BAM, Berlin, Germany DA - 09.04.2019 KW - Aerial robot KW - Gas tomography KW - Plume KW - TDLAS PY - 2019 AN - OPUS4-47800 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Neumann, Patrick P. A1 - Hüllmann, Dino A1 - Tiebe, Carlo T1 - KonSens (Kommunizierende Sensorsysteme für die Bauteil- und Umweltüberwachung) - Projektergebnisse N2 - Im Projekt KonSens werden für die Anwendungsbeispiele bauteilintegrierte Sensorik für Betonkomponenten und mobile Multigassensorik Sensorsysteme in Form von Funktionsmustern entwickelt, validiert und angewendet. Schwerpunkte liegen einerseits in der Detektion und Bewertung von Korrosionsprozessen in Beton und andererseits in der Detektion und Quantifizierung sehr geringer Konzentrationen toxischer Gase in der Luft. Dabei ist die Adaption der sensorischen Methoden aus dem Labor in reale Messumgebungen inklusive geeigneter Kommunikationstechnik ein wichtiger Aspekt. T2 - NetMon International training course - Low-cost Environmental Monitoring CY - BAM, Berlin, Germany DA - 09.04.2019 KW - Umweltmonitoring KW - Bauwerksüberwachung KW - RFID-Sensorsysteme KW - pH-Sensor KW - Fluoreszenzsensoren PY - 2019 AN - OPUS4-47763 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüllmann, Dino A1 - Neumann, Patrick P. A1 - Bartholmai, Matthias A1 - Tiebe, Carlo A1 - Paul, Niels A1 - Lilienthal, A. J. T1 - Wind Vector Estimation on Multirotor Aircraft N2 - An equation for wind vector estimation using a multirotor aircraft as a flying anemometer is shown. To compute the wind vector an estimate of the thrust of the aircraft is required, which is related to the rotational speed of the rotors. Hence, a sensing system for the rotational speed using phototransistors is presented. T2 - NetMon International training course - Low-cost Environmental Monitoring CY - BAM, Berlin, Germany DA - 09.04.2019 KW - Anemometer KW - Phototransistor KW - Thrust KW - Wind PY - 2019 AN - OPUS4-47801 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo A1 - Neumann, Patrick P. A1 - Hüllmann, Dino A1 - Bartholmai, Matthias A1 - Hofmann, Michael T1 - VDI/VDE 3518 Technische Richtlinie für Multigassensoren N2 - Der Beitrag präsentiert die erarbeiteten technischen Richtlinien zur Anwendung und Prüfung von Multigassensoren innerhalb der Richtlinienreihe VDI/VDE 3518 sowie in diesem Zusammenhang die Möglichkeiten der Sensorprüfung im akkreditierten Prüflabor des Fachbereichs 8.1 der BAM. Im Speziellen wird das in Kürze veröffentlichte Blatt 3 der Richtlinienreihe vorgestellt, das Bezug auf Multigassensoren für geruchsbezogene Messungen mit elektronischen Nasen nimmt. T2 - NetMon International training course - Low-cost Environmental Monitoring CY - BAM, Berlin, Germany DA - 09.04.2019 KW - Multigassensoren KW - Prüfung KW - Richtlinie PY - 2018 AN - OPUS4-47885 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Bartholmai, Matthias A1 - Grotelüschen, Bjarne A1 - Strangfeld, Christoph T1 - Towards Autonomous NDT Inspection: Setup and Validation of an Indoor Localization System N2 - Monitoring and maintenance of civil infrastructure are of great importance, as any undetected damage can cause high repair costs, unintended deadtime, or endanger structural integrity. The inspection of large concrete structures such as bridges and parking lots is particularly challenging and time-consuming. Traditional methods are mostly manual and involve mapping a grid of measurement lines to record the position of each measurement. Current semi-automated methods, on the other hand, use GPS or tachymeters for localization but still require trained personnel to operate. An entirely automated approach using mobile robots would be more cost- and time-efficient. While there have been developments in using GPS-enabled mobile robots for bridge inspection, the weak signal strength in indoor areas poses a challenge for the automated inspection of structures such as parking lots. This paper aims to develop a solution for the automated inspection of large indoor concrete structures by addressing the problem of robot localization in indoor spaces and the automated measurement of concrete cover and rebar detection. T2 - 39th Danubia-Adria Symposium on Advances in Experimental Mechanics CY - Siófok, Hungary DA - 26.09.2023 KW - NDT Inspection KW - Mobile Robot KW - Indoor Localization KW - Setup and Validation PY - 2023 AN - OPUS4-58662 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Schartel, Bernhard T1 - Comprehensive Fire Behaviour Assessment of Nanocomposites T2 - 9th European Meeting on Fire Retardancy and Protection of Materials, FRPM '03 CY - Lille, France DA - 2003-09-17 PY - 2003 AN - OPUS4-4615 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Johann, Sergej A1 - Strangfeld, Christoph A1 - Müller, Maximilian A1 - Mieller, Björn T1 - RFID sensor systems embedded in concrete – validation experiments for long-term monitoring N2 - Structural Health Monitoring (SHM) is an important part of buildings surveillance and maintenance to detect material failure as early as possible and to contribute in protection of structures and their users. The implementation of Radio Frequency Identification (RFID) sensor systems without cable connection and battery into building components offers innovative possibilities to enable long-term in-situ SHM of addressed structures, bridges. The objectives of the presented study are complete embedding of RFID sensors systems in concrete, full passive communication with the systems, at best for the whole life span of structures. One challenge for this task is the highly alkaline environment in concrete, which requires non-degrading and robust encapsulation. Further Requirements are passive communication and energy supply, appropriate antenna design, placement and fixation in concrete, and the selection and implementation of sensors and connections. The concept is to develop and optimize a simple and robust system, which meets the requirements, as well as comprehensive validation in concrete specimen and real world applications. Two different systems were developed (HF and UHF RFID, respectively). First tasks were the implementation of analog sensors using the superposition principle for the signal adaption. Investigation of suitable materials for robust encapsulation and sensor protection against basic environments. Four materials were investigated in pH 13 solution for 14 days - 3D-Printer-Polymer was completely resolved - PVC has no noticeable decrease in weight - (VitaPro) glass filter for the sensor protector, has weight loss 2.7 % - The epoxy resin has increased by 1.8 % due to moisture expansion Different concrete samples were prepared for the validation of the systems. RFID sensors were embedded in different integration depths. Investigate the energy- and data transfer through concrete, also with varying moisture content. Additionally, signal strength data was used to optimize and validate the antenna characteristics in concrete. Next steps are to guarantee a sufficient energy supply for UHF RFID systems embedded in different concrete mixtures and further embedding the HF and UHF RFID systems in real bridges and buildings to validate the long term monitoring. T2 - DGZfP-Jahrestagung 2017 CY - Koblenz, Germany DA - 22.05.2017 KW - RFID sensors KW - Long-term requirements KW - Structural health monitoring KW - Passive RFID KW - Sensor requirements KW - Sensors in concrete KW - Smart structures PY - 2017 AN - OPUS4-40348 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Hüllmann, Dino A1 - Neumann, Patrick P. A1 - Scheuschner, Nils A1 - Lilienthal, A.J. T1 - Experimental Validation of the Cone-Shaped Remote Gas Sensor Model N2 - Remote gas sensors mounted on mobile robots enable the mapping of gas distributions in large or hardly accessible areas. A challenging task, however, is the generation of threedimensional distribution maps from these gas measurements. Suitable reconstruction algorithms can be adapted, for instance, from the field of computed tomography (CT), but both their performance and strategies for selecting optimal measuring poses must be evaluated. For this purpose simulations are used, since, in contrast to field tests, they allow repeatable conditions. Although several simulation tools exist, they lack realistic models of remote gas sensors. Recently, we introduced a model for a Tunable Diode Laser Absorption Spectroscopy (TDLAS) gas sensor taking into account the conical shape of its laser beam. However, the novel model has not yet been validated with experiments. In this paper, we compare our model with a real sensor device and show that the assumptions made hold. T2 - IEEE Sensors 2019 CY - Montreal, Canada DA - 27.10.2019 KW - Remote gas sensor model KW - TDLAS KW - Gas dispersion simulation PY - 2019 AN - OPUS4-49549 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -