TY - CONF A1 - Bartholmai, Matthias A1 - Neumann, Patrick P. A1 - Kohlhoff, Harald A1 - Daum, Werner T1 - Multi-sensor systems for safety-related monitoring T2 - Sensor 2013 - 16th International conference on sensors and measurement technology CY - Nürnberg, Germany DA - 2013-05-14 KW - Multi-sensor system KW - Condition monitoring KW - Safety management KW - Hazardous scenarios KW - Data-fusion PY - 2013 SN - 978-3-9813484-3-9 DO - https://doi.org/10.5162/sensor2013/B5.2 N1 - Serientitel: AMA Conferences – Series title: AMA Conferences SP - 268 EP - 272 AN - OPUS4-28518 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilder, Constanze A1 - Hofmann, Detlef A1 - Kohlhoff, Harald A1 - Habel, Wolfgang ED - Ramos, G. A. T1 - Structure-integrated fiber-optic strain wave sensor for concrete pile testing and monitoring N2 - Reinforced concrete piles are used in case of structures that are constructed on soft ground to transfer the loads into deeper strata with sufficient bearing capacity. In order to determine the pile’s behavior and possible damage, static and dynamic pile tests are carried out. Dynamic measurements taken from the pile head can show the bearing behavior and structural integrity by using the theory of wave propagation. In order to receive more precise information about the pile features, now, a string of sensors is embedded at different levels of the pile. A fiber optic strain wave sensor, based on the extrinsic Fabry-Perot interferometer (EFPI), has already been developed and tested in full-scale field tests by Schallert (2010). It was possible to detect the introduced deformation caused by the static load and the dilatational wave during dynamic loading. Although the full-scale tests were successful, the engineering design of the sensor body left room - from the economical point of view - to be optimized. After laboratory tests with the optimized sensor, a cast-in-situ bored pile has been built at the BAM Test Site Technical Safety in Horstwalde, South of Berlin. Additionally to the EFPI sensors, fiber Bragg grating (FBG) sensors, temperature sensors and resistance strain gauge (RSG) sensors are embedded in order to compare the signals with each other. In this paper, the modified sensor and the Setup of the cast-in-situ bored pile along with results of dynamic tests are shown. T2 - SHMII-5 - 5th International conference on structural health monitoring of intelligent infrastructure CY - Cancún, Mexico DA - 11.12.2011 KW - Fibre optic sensors KW - Monitoring KW - Concrete pile KW - Foundation KW - Integrity testing PY - 2011 IS - Topic_04.Cat_4.2-abs002 SP - 1 EP - 8 PB - National Autonomous University of Mexico CY - Mexico City AN - OPUS4-25142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kohlhoff, Harald A1 - Ullner, Christian T1 - Verification of the standard machine for the macro range of instrumented indentation test N2 - A new calibration machine according to the requirements given by ISO 14577-3 [1] was described in [2]. The results of the verification are reported in this paper. It is shown that the calibration machine can be used as a national standard for the materials parameter of the instrumented indentation test. T2 - HARDMEKO 2007 - Recent Advancement of Theory and Practice in Hardness Measurement CY - Tsukuba, Japan DA - 2007-11-19 KW - Indentation KW - Standard KW - Verification PY - 2007 IS - CD-ROM SP - 30 EP - 34 CY - Tsukuba, Japan AN - OPUS4-16319 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kohlhoff, Harald A1 - Ullner, Christian T1 - Design and capability of a new calibration machine for the macro range of instrumented indentation test N2 - The instrumented indentation test provides a versatile method to determine several materials parameter. In order to provide reference specimens, a calibration machine according to ISO 14577-3 is designed for the macro range. Using innovative technology, the new machine design may lead to a standard solution not only for calibration machines. T2 - XVIII IMEKO World Congress CY - Rio de Janeiro, Brazil DA - 2006-09-17 KW - Indentation KW - Reference KW - Uncertainty KW - Machine design PY - 2006 SP - 1 EP - 5(?) PB - Letra Capital Ed. CY - Rio de Janeiro AN - OPUS4-14222 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Habel, Wolfgang A1 - Schukar, Vivien A1 - Mewis, Franziska A1 - Kohlhoff, Harald ED - Yang, M. ED - Wang, D. ED - Rao, Y. T1 - Experimental validation of applied strain sensors - importance, methods and still unsolved challenges N2 - Fiber-optic strain sensors are increasingly used in very different technical fields. Sensors are provided with specifications defined by the manufacturer or ascertained by the interested user. If deformation sensors are to be used to evaluate the long-term behavior of safety-relevant structures or to monitor critical structure components, their performance and signal stability must be of high quality to enable reliable data recording. The measurement system must therefore be validated according to established technical rules and standards before its application and after. In some cases, not all details of the complex characteristic and performance of applied fiber-optic sensors are sufficiently understood, or can be validated because of a lack of knowledge and methods to check the sensors' behavior. This contribution focusses therefore on the importance of serious validation in avoiding a decrease or even deterioration of the sensors' function. Methods for validation of applied sensors are discussed and should reveal weaknesses in validation of embedded or integrated fiber-optic deformation and/or strain sensors. An outlook to some research work that has to be carried out to ensure a well-accepted practical use of fiber-optic sensors is given. T2 - 4th Asia Pacific optional sensors conference CY - Wuhan, China DA - 2013-10-15 KW - Fiber-optic sensor KW - Strain sensor KW - Reliability KW - Durability KW - Sensor characteristics KW - Application-related changes KW - Adhesive stability KW - Validation PY - 2013 DO - https://doi.org/10.1117/12.2036591 SN - 0277-786X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE VL - 8924 SP - 892410-1 - 892410-6 AN - OPUS4-29908 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gawlitza, Kornelia A1 - Johann, Sergej A1 - Mansurova, Maria A1 - Kohlhoff, Harald A1 - Tiebe, Carlo A1 - Bell, Jérémy A1 - Bartholmai, Matthias A1 - Rurack, Knut T1 - Semi-automatic Measurement Device for Long-Term Monitoring of Ammonia in Gas Phase N2 - In the present paper the development of a semi-automated device for long-term monitoring of gaseous ammonia is described. A sensor material was produced that changes its optical properties in the pres-ence of low concentrations of ammonia in air. The implementation into an electronic device enables precise, simple, economic and fast monitoring of low concentrations of harmful gases, like ammonia, and hence can help to improve the climate monitoring in livestock housing, barns or stables. T2 - SMSI 2021 CY - Online meeting DA - 03.05.2021 KW - Spectroscopy KW - Embedded sensor KW - Environment KW - Air quality PY - 2021 SP - 133 EP - 134 AN - OPUS4-52576 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Winkler, Nicolas P. A1 - Neumann, Patrick P. A1 - Kohlhoff, Harald A1 - Erdmann, Jessica A1 - Schaffernicht, Erik A1 - Lilienthal, Achim J. T1 - Development of a Low-Cost Sensing Node with Active Ventilation Fan for Air Pollution Monitoring N2 - A fully designed low-cost sensing node for air pollution monitoring and calibration results for several low-cost gas sensors are presented. As the state of the art is lacking information on the importance of an active ventilation system, the effect of an active fan is compared to the passive ventilation of a lamellar structured casing. Measurements obtained in an urban outdoor environment show that readings of the low-cost dust sensor (Sharp GP2Y1010AU0F) are distorted by the active ventilation system. While this behavior requires further research, a correlation with temperature and humidity inside the node shown. T2 - SMSI 2021 Conference: Sensor and Measurement Science International CY - Online meeting DA - 03.05.2021 KW - Wireless sensing node KW - Air pollution KW - Sensor network KW - Environmental monitoring PY - 2021 DO - https://doi.org/10.5162/SMSI2021/D3.5 VL - 2021 SP - 260 EP - 261 AN - OPUS4-52607 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej A1 - Tiebe, Carlo A1 - Kohlhoff, Harald A1 - Bartholmai, Matthias T1 - Feasibility Study for Safe Workplaces through automation and digitalization technology with redesigned Smart Sensors and LoRaWAN Monitoring System N2 - This project addresses the application of safe and healthy workplaces in offices, chemical laboratories and other workplaces where indoor air quality plays an important role. The LoRaWAN (Long Range Wide Area Network) is used as a communication interface to make sensor data globally accessible. The objectives of the project are to create a sensor node and an online and offline system that collects the data from the sensor nodes and stores it on a local server, in a cloud, and also locally on the node to prevent communication failures. An important point in this project is the development of the sensor nodes and the placement of these in the premises, thus no development work is involved in Building the infrastructure. T2 - SMSI 2021 CY - Online meeting DA - 03.05.2021 KW - Smart sensors KW - Air quality monitoring KW - LoRaWAN KW - VOC KW - Multisensor system PY - 2021 SP - 230 EP - 231 AN - OPUS4-52649 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Kohlhoff, Harald A1 - Johann, Sergej A1 - Erdmann, Jessica A1 - Winkler, Nicolas P. ED - Kourkoulis, S. K. T1 - The RASEM System: A Technical Overview N2 - Occupational health is an important topic, especially in industry, where workers are exposed to airborne by-products (e.g., dust particles and gases). Therefore, continuous monitoring of the air quality in industrial environments is crucial to meet safety standards. For practical and economic reasons, high-quality, costly measurements are currently only carried out sparsely, both in time and space, i.e., measurement data are collected in single day campaigns at selected locations only. The project “Robot-assisted Environmental Monitoring for Air Quality Assessment in Industrial Scenarios” (RASEM) addresses this issue by bringing together the benefits of both – low- and high-cost – measuring technologies enabling costefficient long-term air quality monitoring in realtime: A stationary network of low-cost sensors that is augmented by mobile units carrying high-quality sensors. By mapping the distribution of gases and particles in industrial environments with the proposed RASEM system, measures can be identified to improve on-site working conditions much faster than using traditional methods. In this paper, we detail the technical aspects of RASEM and introduce the mobile platforms used. T2 - 38th Danubia-Adria Symposium on Advances in Experimental Mechanics CY - Poros, Greece DA - 20.09.2022 KW - RASEM KW - Dust sensor KW - Low-cost KW - Sensor network KW - Ground Robot KW - Aerial Robot PY - 2022 SP - 1 EP - 2 CY - Athens, Greece AN - OPUS4-55915 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüllmann, Dino A1 - Kohlhoff, Harald A1 - Erdmann, Jessica A1 - Neumann, Patrick P. ED - Aulova, Alexandra ED - Rogelj Ritonja, A. ED - Emri, I. T1 - Current-independent torque control of PMSM servo drives N2 - A permanent-magnet synchronous motor (PMSM) is controlled using measurements from a digital, optical incremental encoder. The motor speed is estimated from these measurement. Basic performance results are presented. T2 - 33rd Danubia Adria Symposium on Advances in Experimental Mechanics CY - Portorož, Slovenia DA - 20.09.2016 KW - BLDC KW - PMSM KW - Motor control KW - Servo drive PY - 2016 SN - 978-961-94081-0-0 SP - 172 EP - 173 PB - Narodna in univerzitetna knjižnica CY - Ljubljana, Slovenia AN - OPUS4-37813 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -