Articles | Volume 3, issue 1
Regular research article 12 Jun 2014
Regular research article | 12 Jun 2014
Multi-channel IR sensor system for determination of oil degradation
T. Bley et al.
No articles found.
Tanja Dorst, Yannick Robin, Sascha Eichstädt, Andreas Schütze, and Tizian Schneider
J. Sens. Sens. Syst., 10, 233–245,Short summary
Synchronization problems within distributed sensor networks are a major challenge in the field of Industry 4.0. In this paper, artificially generated time shifts between sensor data and their influence on remaining useful lifetime prediction of electromechanical cylinders are investigated. It is shown that time shifts within sensor data lead to poor remaining useful lifetime predictions. However, this prediction can be significantly improved using various methods as shown in this contribution.
Tobias Baur, Manuel Bastuck, Caroline Schultealbert, Tilman Sauerwald, and Andreas Schütze
J. Sens. Sens. Syst., 9, 411–424,Short summary
Applications like air quality, fire detection and detection of explosives require selective and quantitative measurements in an ever-changing background of interfering gases. One main issue hindering the successful implementation of gas sensors in real-world applications is the lack of appropriate calibration procedures for advanced gas sensor systems. This article presents a calibration scheme for gas sensors based on gas profiles with unique randomized gas mixtures.
Caroline Schultealbert, Iklim Uzun, Tobias Baur, Tilman Sauerwald, and Andreas Schütze
J. Sens. Sens. Syst., 9, 283–292,Short summary
We present a work on gas sensors that can for example be used for the assessment of indoor air quality. These sensors suffer from deterioration by siloxanes, so we investigated these effects by a distinct operation mode and exposition to this gas that allows us to interpret different reactions on the sensor surface. We found that all processes on the sensor surface are slowed down by this treatment and a self-compensation by the evaluation of oxygen adsorption processes is likely to be found.
Marius Rodner, Manuel Bastuck, Andreas Schütze, Mike Andersson, Joni Huotari, Jarkko Puustinen, Jyrki Lappalainen, and Tilman Sauerwald
J. Sens. Sens. Syst., 8, 261–267,Short summary
To fulfil today's requirements, gas sensors have to become more and more sensitive and selective. In this work, we present a novel method to significantly enhance the effect of gate bias on the response of a SiC field-effect transistor by placing a lithium-doped tungsten oxide film beneath the gate. This enhancement, compared to undoped samples, opens new perspectives for static and transient signal generation, e.g. gate bias-cycled operation, and, thus, increasing sensitivity and selectivity.
Henrik Lensch, Manuel Bastuck, Tobias Baur, Andreas Schütze, and Tilman Sauerwald
J. Sens. Sens. Syst., 8, 161–169,Short summary
The measurement of humidity in industrial applications is still an important research issue. Especially under rough operation conditions the current humidity sensor comes to its limitations. To this end, we are developing an integrated sensor system using a metal oxide sensor with impedance spectroscopy as multi-signal generation allowing the discrimination of humidity and reducing gases. The submitted paper focuses on the modeling of the humidity-dependent aspects of impedance.
Manuel Bastuck, Tobias Baur, and Andreas Schütze
J. Sens. Sens. Syst., 7, 489–506,Short summary
Predictions about systems too complex for physical modeling can be made nowadays with data-based models. Our software DAV³E is an easy way to extract relevant features from cyclic raw data, a process often neglected in other software packages, based on mathematical methods, incomplete physical models, or human intuition. Its graphical user interface further provides methods to fuse data from many sensors, to teach a model the prediction of new data, and to check the model’s performance.
Tobias Baur, Caroline Schultealbert, Andreas Schütze, and Tilman Sauerwald
J. Sens. Sens. Syst., 7, 411–419,Short summary
A novel method for the detection of short pulses of gas at very low concentrations is presented. Applying the method to a doped SnO2 detector, gas pulses down to a dosage of 1 ppb times seconds can be detected. The gas transport inside the detector is simulated using the finite element method (FEM) to optimize the gas transport and to keep response and recovery time as short as possible. With this approach, we have demonstrated a detection limit for ethanol below 47 fg.
Andreas Schütze, Nikolai Helwig, and Tizian Schneider
J. Sens. Sens. Syst., 7, 359–371,Short summary
“Industrie 4.0” or the Industrial Internet of Things (IIoT) describe the current (r)evolution in industrial automation and control. This is fundamentally based on smart sensors, which generate data and allow further functionality from self-monitoring and self-configuration to condition monitoring of complex processes. The paper reviews the development of sensor technology over the last 2 centuries and highlights some of the potential that can be achieved with smart sensors and data analysis.
Martin Leidinger, Joni Huotari, Tilman Sauerwald, Jyrki Lappalainen, and Andreas Schütze
J. Sens. Sens. Syst., 5, 147–156,Short summary
For the application of indoor air quality monitoring, two types of tungsten oxide gas sensor layers were prepared via pulsed laser deposition. Analysis of the structure of the produced layers showed that they consist of nanoparticles and agglomerates of nanoparticles. The sensors showed significant sensitivity and selectivity towards naphthalene in the ppb concentration range. The results were achieved using temperature cycled operation of the sensors and pattern recognition signal treatment.
M. Schüler, T. Sauerwald, and A. Schütze
J. Sens. Sens. Syst., 4, 305–311,Short summary
We study the effect of HMDSO vapor on an SnO2-based gas sensor in temperature cycled operation (TCO). The poisoning can be quantified at early stages with a resolution of ±85 ppm*min using TCO. This approach provides a simple method for early detection of HMDSO poisoning. The stability of gas discrimination by linear discriminant analysis (LDA) can be improved using normalization, which in turn facilitates a more accurate determination of the poisoning state by hierarchical LDA discrimination.
B. Schmitt, C. Kiefer, and A. Schütze
J. Sens. Sens. Syst., 4, 239–247,Short summary
A novel sensor principle for determining binary fluid mixtures of known components is presented. A bluff body is placed in the fluid channel, causing the formation of a stationary pair of vortices behind the body. The length of the vortex pair depends on the mixture’s viscosity and thus its composition. It is measured by placing a microheater in the vortex area and making use of forced convection which changes with the size of the vortices.
D. Puglisi, J. Eriksson, C. Bur, A. Schuetze, A. Lloyd Spetz, and M. Andersson
J. Sens. Sens. Syst., 4, 1–8,Short summary
This study aims at the development of high-performance and cost-efficient gas sensors for sensitive detection of three specific hazardous gases, i.e., formaldehyde, naphthalene, and benzene, commonly present in indoor environments in concentrations of health concern. We used silicon carbide field effect transistors to investigate the sensor performance and characteristics under different levels of relative humidity up to 60%, demonstrating excellent detection limits in the sub-ppb range.
C. Bur, M. Bastuck, A. Schütze, J. Juuti, A. Lloyd Spetz, and M. Andersson
J. Sens. Sens. Syst., 3, 305–313,
M. Leidinger, T. Sauerwald, W. Reimringer, G. Ventura, and A. Schütze
J. Sens. Sens. Syst., 3, 253–263,Short summary
An approach for detecting hazardous volatile organic compounds (VOCs) in ppb and sub-ppb concentrations is presented. Using metal oxide semiconductor (MOS) gas sensors in temperature cycled operation, VOCs in trace concentrations are successfully identified against a varying ethanol background of up to 2 ppm. For signal processing, linear discriminant analysis is applied to single sensor data and sensor fusion data. Integrated gas sensor systems using the same MOS sensors were characterized.
M. Schüler, T. Sauerwald, and A. Schütze
J. Sens. Sens. Syst., 3, 213–221,
M. Bastuck, C. Bur, A. Lloyd Spetz, M. Andersson, and A. Schütze
J. Sens. Sens. Syst., 3, 9–19,
Related subject area
Sensor principles and phenomena: Optical and infrared sensorsCharacterization of specular freeform surfaces from reflected ray directions using experimental ray tracingIterative feature detection of a coded checkerboard target for the geometric calibration of infrared camerasThe size-of-source effect in thermographyMethod for fast determination of the angle of ionizing radiation incidence from data measured by a Timepix3 detectorComparison of laser-based photoacoustic and optical detection of methaneMetrological characterization and calibration of thermographic cameras for quantitative temperature measurementDetection of plastics in water based on their fluorescence behaviorAnalysis of photoelastic properties of monocrystalline siliconEvaluation of optical fibre sensors in the electrical domainInfrared-based sensor system for contactless monitoring of wetness and iceMiniaturized photoacoustic detection of organofluorine-based refrigerantsCharacterization, calibration and validation of an industrial emissometerMeasurement of the absolute spectral responsivity in the mid-infrared based on the cryogenic electrical substitution radiometer and an optimized thermopile detectorQuantitative measurement of combustion gases in harsh environments using NDIR spectroscopyValidation of three-component wind lidar sensor for traceable highly resolved wind vector measurementsComparison between different fiber coatings and adhesives on steel surfaces for distributed optical strain measurements based on Rayleigh backscatteringCrack luminescence as an innovative method for detection of fatigue damageTemperature sensing in underground facilities by Raman optical frequency domain reflectometry using fiber-optic communication cablesEvaluation of the pH-sensitive swelling of a hydrogel by means of a plasmonic sensor substrateTemperature reconstruction of infrared images with motion deblurringTSA infrared measurements for stress distribution on car elementsTransmitted light pH optode for small sample volumesPurity monitoring in medical gas supply lines with quantum cascade laser technologyEfficient thermal infrared emitter with high radiant powerRefractive index sensing of gases based on a one-dimensional photonic crystal nanocavityDevelopment of a portable active long-path differential optical absorption spectroscopy system for volcanic gas measurementsThermal imaging as a modern form of pyrometry
Tobias Binkele, David Hilbig, Mahmoud Essameldin, Thomas Henning, Friedrich Fleischmann, and Walter Lang
J. Sens. Sens. Syst., 10, 261–270,Short summary
The development of optical design is characterized by the desire for more applications and better performance. The latest result of this development is freeform optics offering almost unlimited possibilities for the designers. However, an optical component has also to be manufactured and tested by metrology. We propose a measurement technique for the surface characterization of freeform optical components and highlight the possible error sources and their influence on the measurement result.
Sebastian Schramm, Jannik Ebert, Johannes Rangel, Robert Schmoll, and Andreas Kroll
J. Sens. Sens. Syst., 10, 207–218,Short summary
During the geometric calibration of infrared cameras, the parameters that describe where object points are mapped onto thermal images are determined. The required reference data is obtained by capturing so-called calibration targets. In established approaches, it is difficult to estimate the lens distortions precisely. A newly developed target and its evaluation algorithm make it possible to increase the sensitivity of the calibration by finding reference points close to image borders.
Helmut Budzier and Gerald Gerlach
J. Sens. Sens. Syst., 10, 179–184,Short summary
In thermometry, the displayed temperature value of an object depends on the size of the object. This behaviour, the size-of-source effect, might be a major cause of measurement uncertainty in a thermoscene. The influence of diffraction and digitization can be described advantageously with the modulation transfer function. Especially with very small objects the displayed temperatures are too low. When imaging large objects, not only the edge areas are affected, but also the entire image.
Felix Lehner, Jürgen Roth, Oliver Hupe, Marc Kassubeck, Benedikt Bergmann, Petr Mánek, and Marcus Magnor
J. Sens. Sens. Syst., 10, 63–70,
Thomas Strahl, Johannes Herbst, Eric Maier, Sven Rademacher, Christian Weber, Hans-Fridtjof Pernau, Armin Lambrecht, and Jürgen Wöllenstein
J. Sens. Sens. Syst., 10, 25–35,Short summary
For safety, environmental and economic reasons, methane leak detection is one of the most requested tasks for gas measurement devices. This paper compares the performance of a laser-based optical and acoustical detection scheme at different wavelengths and laser types, respectively. This forms a good basis for further developments of methane leak detection devices or can help to choose the right configuration for a certain methane leak detection application.
Sebastian König, Berndt Gutschwager, Richard Dieter Taubert, and Jörg Hollandt
J. Sens. Sens. Syst., 9, 425–442,Short summary
We present the metrological characterization and calibration of three different types of thermographic cameras for quantitative temperature measurement traceable to the International Temperature Scale (ITS-90). Relevant technical specifications are determined according to the requirements given in the series of Technical Directives VDI/VDE 5585. For the IETD and the NU, we also show how a significant improvement in the parameters can be achieved with the help of the data reference method.
Maximilian Wohlschläger and Martin Versen
J. Sens. Sens. Syst., 9, 337–343,
Markus Stoehr, Gerald Gerlach, Thomas Härtling, and Stephan Schoenfelder
J. Sens. Sens. Syst., 9, 209–217,Short summary
Photoelasticity is considered a useful measurement tool for non-destructive and contactless determination of mechanical stresses or strains in the production of silicon wafers. In this work, a detailed derivation for the anisotropic stress-optic law is presented, and the corresponding stress-optical parameters are measured.
Ulrich Nordmeyer, Niels Neumann, Xiaozhou Wang, Dirk Plettemeier, Torsten Thiel, and Konstantin Kojucharow
J. Sens. Sens. Syst., 9, 199–208,Short summary
A completely new evaluation method for optical sensors is investigated in this paper. It originates from research that integrates optical sensors into radio-over-fibre networks. The laboratory-based experimental set-up is explained, and the findings are validated by a comparison to the conventional evaluation scheme. Finally, the work provides a detailed mathematical model to understand the implications of this new read-out method for practical applications.
Lakshan Tharmakularajah, Jakob Döring, and Karl-Ludwig Krieger
J. Sens. Sens. Syst., 9, 133–141,Short summary
In order to differentiate between a wet and a dry road surface, the water film height should be measured by using an infrared-based sensor system. By means of different wavelengths, it is also possible to distinguish between ice and water. In this article, a sensor system for the determination of the physical state of water on different surfaces using infrared LEDs and one photodiode is presented. This shall serve as a basis for the calculation of the road condition.
Mahmoud El-Safoury, Christian Weber, Olaf Kiesewetter, Yvonne Hespos, André Eberhardt, Katrin Schmitt, and Jürgen Wöllenstein
J. Sens. Sens. Syst., 9, 89–97,Short summary
The refrigerant R134a is classified as a greenhouse gas and was banned from use (in vehicles) by the European Union in 2017 due to its contribution to global warming. The more expensive alternative refrigerant R1234yf is considered an environmentally less harmful alternative owing to its significantly lower global warming potential. Our newly developed gas detector can detect both refrigerants separately and, thus, help prevent the use of illegal gas mixtures that contain both refrigerants.
Elena Kononogova, Albert Adibekyan, Christian Monte, and Jörg Hollandt
J. Sens. Sens. Syst., 8, 233–242,
Tobias Pohl, Peter Meindl, Uwe Johannsen, Dieter Taubert, and Lutz Werner
J. Sens. Sens. Syst., 8, 195–205,Short summary
The Physikalisch-Technische Bundesanstalt (PTB) expanded its capabilities in the International System of Units (SI)-traceable absolute measurement of radiant power into the spectral range of the mid-infrared (MIR) by implementing additional MIR laser radiation sources at one of the PTB's cryogenic electrical substitution radiometer facilities. This extension enables absolute calibrations of the spectral responsivity of detectors in the MIR with low uncertainty.
Christian Niklas, Stephan Bauke, Fabian Müller, Kai Golibrzuch, Hainer Wackerbarth, and Georgios Ctistis
J. Sens. Sens. Syst., 8, 123–132,Short summary
We present in our paper two types of optical sensors that are capable of measuring the environmentally significant gases such as carbon oxide and dioxide as well as methane and water through absorption of light even in harsh environments of high temperature and pressure. Thus the sensors render it possible to measure inside combustion engines or in civilian fireplaces, which is necessary to meet the increasing demands of environmental protection regulations.
Stefan Oertel, Michael Eggert, Christian Gutsmuths, Paul Wilhelm, Harald Müller, and Helmut Többen
J. Sens. Sens. Syst., 8, 9–17,Short summary
Traceable wind velocity measurements with high resolution play a critical role in the field of wind energy. In this article we present a novel bistatic wind lidar system that has a high spatial and temporal resolution and a reduced measurement uncertainty compared to conventional systems as evidenced by comparison measurements. A first validation measurement in a wind tunnel with a laser Doppler anemometer as a flow velocity reference confirms the high accuracy of the bistatic lidar system.
Martin Weisbrich and Klaus Holschemacher
J. Sens. Sens. Syst., 7, 601–608,Short summary
The study describes how distributed optical strain measurement can be applied to steel surfaces. With the method presented, strain transfers from the substrate to the fiber core can be achieved that are almost identical to those of the reference measurement, especially with Ormocer® and polyimide coating. The research results are to be used in the future for strain measurement in concrete construction on reinforcing steel.
Ruben Makris, Falk Hille, Marc Thiele, Dirk Kirschberger, and Damian Sowietzki
J. Sens. Sens. Syst., 7, 259–266,Short summary
In structural parts under vibrational loading fatigue cracks can initiate and grow, which can lead to structural failure. Conventional non-destructive testing methods for crack detection provide just a snapshot of fatigue crack evolution, whereas crack luminescence coating realizes clear visibility of the entire crack formation. Fatigue causing cyclic tensile tests and examinations on special test bodies allowing control of the crack opening width demonstrate a high sensitivity of the coating.
Markus Brüne, Wilhelm Furian, Wieland Hill, and Andreas Pflitsch
J. Sens. Sens. Syst., 7, 85–90,Short summary
The climate conditions in underground transportation facilities, especially the current airflow in terms of direction and speed, are the key factor driving smoke propagation in the case of a tunnel fire. Sensing this airflow is cost-intensive. Therefore, this paper focuses on gaining the information from temperature sensing along the tunnels using already installed optical fibers normally used for communications. This technique can replace thousands of temperature sensors.
Christoph Kroh, Roland Wuchrer, Margarita Günther, Thomas Härtling, and Gerald Gerlach
J. Sens. Sens. Syst., 7, 51–55,Short summary
The inline monitoring of parameters in aqueous liquids is facing an increasing demand in many application areas. In this paper we report on an optical monitoring of the pH value in liquids by means of a sensitive hydrogel, which can be applied in the physiological range. Our results indicate a nearly linear dependency between pH value and hydrogel swelling. Furthermore, we show an improvement of the response time by a factor of 2 in comparison to other systems exploiting this kind of hydrogel.
J. Sens. Sens. Syst., 7, 13–20,Short summary
Images of an infrared camera show blurring effects while recording a moving object. Not only the contrast is corrupted by the motion but also the object temperature seems to be lower. It is shown how such images and the true temperature with a good approximation can be restored. Since the detection mechanism of an infrared camera is different from usual digital cameras, also the restoration is different. Examples are presented for motion deblurring used to restore images with different motions.
Roberto Marsili and Gianluca Rossi
J. Sens. Sens. Syst., 6, 361–365,Short summary
The car production industry is being subjected to more and more pressing technological challenges. In this framework the use of an advanced measurement technique such as thermoelasticity allows the engineers to have a fast and reliable tool for experimental investigation, optimization and validation of the FEM models. In this work it is shown how the thermoelastic measurement technique can be used to optimize a Ferrari car frame.
Christian Rogge, Steffen Zinn, Paolo Prosposito, Roberto Francini, and Andreas H. Foitzik
J. Sens. Sens. Syst., 6, 351–359,Short summary
This work presents a cost-effective optical-based sensor for pH monitoring of sample volumes less than 150 µL. As part of a bigger project to develop a stand-alone micro bioreactor system, measurements carried out with phenol red and DMEM reported a standard error of calibration in the physiologic pH range (6.5–7.5) of pH ±0.04. Compared to other accessible optical-based sensors this reported system is a good alternative regarding the overall costs of less than EUR 50.
Henrik Zimmermann, Mathias Wiese, Luigi Fiorani, and Alessandro Ragnoni
J. Sens. Sens. Syst., 6, 155–161,Short summary
Because of their direct impact on patients, medical supply lines are under strict regulations and have to be monitored in terms of purity on a regular basis. State-of-the-art measurement solutions do not allow for continuous bedside monitoring. The aim of the presented work is to provide a compact multispecies monitoring system based on the latest quantum cascade laser technologies allowing for the continuous bedside monitoring of medical gases.
T. Ott, M. Schossig, V. Norkus, and G. Gerlach
J. Sens. Sens. Syst., 4, 313–319,
J. Sens. Sens. Syst., 4, 209–215,
F. Vita, C. Kern, and S. Inguaggiato
J. Sens. Sens. Syst., 3, 355–367,
J. Sens. Sens. Syst., 3, 265–271,
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