Journal articles: 'Optical sensor system'

1

Wang, Li Hui, Jian Sun, and Jian Fei Ji. "Optical Current Sensor Technology in Power System." Key Engineering Materials 562-565 (July 2013): 242–46. http://dx.doi.org/10.4028/www.scientific.net/kem.562-565.242.

Full text

Abstract:

With power voltage and capacity improved greatly, power transmission system put a higher demand on reliability and safe operation of electrical equipments. Electromagnetic sensors and other conventional detection equipment can no longer meet the needs of the power system, and new sensing measurement techniques led to optical current and voltage sensing technology. As their unique advantages, optical current sensing technology is get in-depth study and attention, and gradually used in power system engineering applications. Combined with domestic and foreign research progress of optical current sensor, we analyzed the basic principles of the photoelectric sensing technology and problems faced in power system applications and key technologies. Focused on sensing characteristic differences of photoelectric sensors and electromagnetic sensor, we analyzed the effects of photoelectric sensor on protection, monitoring and control, measurement systems in data processing and data transmission, and study the corresponding key technology. Combined with the development of modern power system, we prospect optical current sensor sensing technology opportunities and challenges in smart grid.

APA, Harvard, Vancouver, ISO, and other styles

2

Han, Yan. "The Building of Optical Fiber Network System Using Hetero-Core Fiber Optic Sensors." Advanced Materials Research 571 (September 2012): 342–46. http://dx.doi.org/10.4028/www.scientific.net/amr.571.342.

Full text

Abstract:

We proposed a novel optical sensory nerve network using pulse switch sensors. The pulse switch sensor generates light loss similar to pulse signals only when ON/OFF states change. Therefore, it has less influence on communications quality compared with conventional switch sensor modules as sensor multiplicity increases. Our simulated results demonstrated that the proposed system can improve sensor multiplicity while maintaining the communications and measuring performance with the same quality as a conventional system by appropriately adjusting the initial loss of the pulse switch sensors. In particular, where ON/OFF time intervals follow exponential distributions with mean values of 5 and 300 s, respectively, the insertion loss of hetero-core segments inserted into pulse switch sensors is 0.3 dB, and the pulse switch sensors have curvature from 0.05 to 0.18. Under these conditions, our enhanced system can increase sensor multiplicity to 23 while maintaining link availability of almost 100%, a distinction error ratio of less than 1%, and a duplicated error ratio of about 0.5%.

APA, Harvard, Vancouver, ISO, and other styles

3

Cheng, Tai Hong, Seong Hyun Lim, Chang Doo Kee, and Il Kwon Oh. "Development of Fiber-PZT Array Sensor System." Advanced Materials Research 79-82 (August 2009): 263–66. http://dx.doi.org/10.4028/www.scientific.net/amr.79-82.263.

Full text

Abstract:

In this study, array type fiber-PZT senor systems were newly developed with capabilities of detecting both damage location and monitoring of gas or liquid leakage by applying time-frequency analyses. The system consists of two piezoelectric transducers for the signal receiver and generator applications and three optical fibers for wave propagation. The results showed developed fiber-PZT array sensor can accurately measure the position of crack and its intensity. Also the fluid leakage of methyl alcohol as test specimen, on the plate structure has also been investigated employing the fiber-PZT sensors. The ultrasonic wave optical fiber sensor can be used effectively to monitor changes in structural and chemical properties.

APA, Harvard, Vancouver, ISO, and other styles

4

Babković, Kalman, László F. Nagy, and Damir Krklješ. "Self-Calibrating Optical Displacement Sensor." Key Engineering Materials 543 (March 2013): 59–62. http://dx.doi.org/10.4028/www.scientific.net/kem.543.59.

Full text

Abstract:

Commercially available reflective optical sensors can be used as displacement sensors which in turn can be used in vibration monitoring, positioning, force-measurement and other applications. The sensor output depends in all cases on the distance between the component and a suitable reflective surface. In this paper a sensor system applicable to vibration measurement (e.g. monitoring a vibration-generating machine mounted on elastic isolation mountings) is presented where a special mechanism enables the controlled adjustment of the reflective surfaces position. This feature allows continuous operating point adjustment while the sensor measures vibration. On the other hand, during the intervals when the vibration measurement is not active (e.g. the machine is not in use), the system can be used to automatically calibrate the sensor, i.e. to measure the dependence of the optical sensor output from the distance to the reflective surface. This allows accurate measurements under various circumstances: temperature change, optical component replacement, staining of the reflective surface, ingress of dirt etc. The reflective surface adjustment system is controlled by an embedded digital system which also controls the calibration procedure. Range depends largely on the type of reflective sensor. In case of the component TCRT1000 used in the experiments, range is up to 4 mm.

APA, Harvard, Vancouver, ISO, and other styles

5

S ,, Madhusudhan, Channakeshava K.R ,, and Dr T. Rangaswamy. "Content-Based Image Retrieval System for Optical Fiber Sensor Information Processing." International Journal of Engineering Research 3, no. 6 (June 1, 2014): 398–401. http://dx.doi.org/10.17950/ijer/v3s6/607.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Guo, Shi Sheng, Ying Ying Wang, Chang Wang, and Xiao Hui Liu. "Application of Optical Fiber Sensor System in Offshore Oil Field." Applied Mechanics and Materials 416-417 (September 2013): 971–74. http://dx.doi.org/10.4028/www.scientific.net/amm.416-417.971.

Full text

Abstract:

Optical fiber sensors have been used widely in offshore oilfield. An optical fiber sensor system including an optical fiber sensor testing temperature and pressure under well, a connector connecting the optical fiber sensor with the optical cable, two connectors connecting cables, 3600 meters armoured optical cable and an interrogator was applied in an offshore oil well on Zhoushan island. The temperature and pressure under well have been measured for about two month and the testing results are presented in this paper.

APA, Harvard, Vancouver, ISO, and other styles

7

Wiki, M., H. Gao, M. Juvet, and R. E. Kunz. "Compact integrated optical sensor system." Biosensors and Bioelectronics 16, no. 1-2 (January 2001): 37–45. http://dx.doi.org/10.1016/s0956-5663(00)00131-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Ren, Danyang, Yizhe Sun, Junhui Shi, and Ruimin Chen. "A Review of Transparent Sensors for Photoacoustic Imaging Applications." Photonics 8, no. 8 (August 10, 2021): 324. http://dx.doi.org/10.3390/photonics8080324.

Full text

Abstract:

Photoacoustic imaging is a new type of noninvasive, nonradiation imaging modality that combines the deep penetration of ultrasonic imaging and high specificity of optical imaging. Photoacoustic imaging systems employing conventional ultrasonic sensors impose certain constraints such as obstructions in the optical path, bulky sensor size, complex system configurations, difficult optical and acoustic alignment, and degradation of signal-to-noise ratio. To overcome these drawbacks, an ultrasonic sensor in the optically transparent form has been introduced, as it enables direct delivery of excitation light through the sensors. In recent years, various types of optically transparent ultrasonic sensors have been developed for photoacoustic imaging applications, including optics-based ultrasonic sensors, piezoelectric-based ultrasonic sensors, and microelectromechanical system-based capacitive micromachined ultrasonic transducers. In this paper, the authors review representative transparent sensors for photoacoustic imaging applications. In addition, the potential challenges and future directions of the development of transparent sensors are discussed.

APA, Harvard, Vancouver, ISO, and other styles

9

Loderer, A., and T. Hausotte. "Qualification concept for optical multi-scale multi-sensor systems." Journal of Sensors and Sensor Systems 5, no. 1 (January 14, 2016): 1–8. http://dx.doi.org/10.5194/jsss-5-1-2016.

Full text

Abstract:

Abstract. This article describes a new qualification concept for dimensional measurements on optical measuring systems. Using the example of a prototypical multi-scale multi-sensor fringe projection system for production-related inspections of sheet-bulk metal-formed parts, current measuring procedures of the optical system are introduced. Out of the shown procedures' deficiencies, a new concept is developed for determining the orientations and positions of the sensors' measuring ranges in a common coordinate system. The principle element of the concept is a newly developed flexible reference artefact, adapted to the measuring task of the fringe projection system. Due to its dull surface, the artefact is optimized for optical measuring systems, like the used fringe projection sensors. By measuring the reference artefact with each fringe projection sensor and aligning the resulting data sets on a digital reference model of the artefact, sensor-specific transformation matrices can be calculated which allow transformation of the sensors' data sets into a common coordinate system, without the need for any overlapping areas. This approach is concluded in an automated measuring procedure, using alignment algorithms from commercial available software where necessary. With the automated measuring procedure, geometrical relations between individual measured features can be determined and dimensional measuring beyond the measuring range of a sensor became possible. Due to a series of experiments, the advantages of the new qualification concept in comparison with the current measuring procedures are finally revealed.

APA, Harvard, Vancouver, ISO, and other styles

10

Lee, Woojin, Won-Je Lee, Sang-Bae Lee, and Rodrigo Salgado. "Measurement of pile load transfer using the Fiber Bragg Grating sensor system." Canadian Geotechnical Journal 41, no. 6 (December 1, 2004): 1222–32. http://dx.doi.org/10.1139/t04-059.

Full text

Abstract:

A series of laboratory and field tests were performed to evaluate the applicability of an optical fiber sensor system in the instrumentation of piles. A multiplexed sensor system, constructed by arranging several Fiber Bragg Grating (FBG) sensors along a single line of optical fiber, is capable of measuring local axial strains as a function of wavelength shifts. The distributions of axial load in three model piles and a field test pile evaluated from the strains measured by FBG sensors are found to be comparable, in terms of both magnitude and trend, with those obtained from conventional strain gauges. This suggests that the FBG sensor system is an effective tool for the analysis of the axial load transfer in piles. The successful instrumentation of a soilcement injected precast (SIP) pile using FBG sensors suggests that the use of these sensors in drilled shafts and other types of cast in situ concrete piles is feasible. With the rapid advance of optical fiber sensor technology, the economics of the use of optical fiber sensors in this type of instrumentation is expected to improve significantly in coming years.Key words: pile foundation, load transfer, fiber optic sensor, Fiber Bragg Grating sensor.

APA, Harvard, Vancouver, ISO, and other styles

11

Bassett, J., and G. Walker. "A Split Image Vision Sensor." Journal of Engineering for Industry 117, no. 1 (February 1, 1995): 94–101. http://dx.doi.org/10.1115/1.2803284.

Full text

Abstract:

A vision sensor has been developed that uses only two lenses, a split prism, and a detector to acquire an image. This system uses the split prism to create a split image such that the displacement of the image is proportional to its range from the sensor. Prototype sensors have been examined both theoretically and experimentally, and have been found to measure object ranges with less than ±2 percent error. Acquisition of a single-point depth measurement is sufficiently fast for real-time use, and the optical components needed to build the sensor are inexpensive. The effect that each optical component has on the performance of the sensor is also discussed, and an optimal system design procedure is developed.

APA, Harvard, Vancouver, ISO, and other styles

12

Zhong, Yu Ning, Li Xia Zeng, Shan Ting Ding, and Xiao Li Zhang. "Optimized Design of Sun Position Detection Sensor." Applied Mechanics and Materials 120 (October 2011): 499–503. http://dx.doi.org/10.4028/www.scientific.net/amm.120.499.

Full text

Abstract:

With the object of optical sensor detects the position of the sun, the working principle of the sun position detection system based on four photosensitive devices was analyzed.The sensitive part of this type of sensors was analyzed with optimization. Silicon photocells were selected as optical elements . The main factors and interactions between them which affect the accuracy of the sensor were analyzed using the idea of orthogonal experiment and related software , the optimal combination for the size of the sensor structure was got.

APA, Harvard, Vancouver, ISO, and other styles

13

Jobert, Gabriel, Pierre Barritault, Maryse Fournier, Cyrielle Monpeurt, Salim Boutami, Cécile Jamois, Pietro Bernasconi, Andrea Lovera, Daniele Braga, and Christian Seassal. "Miniature Optical Particle Counter and Analyzer Involving a Fluidic-Optronic CMOS Chip Coupled with a Millimeter-Sized Glass Optical System." Sensors 21, no. 9 (May 3, 2021): 3181. http://dx.doi.org/10.3390/s21093181.

Full text

Abstract:

Our latest advances in the field of miniaturized optical PM sensors are presented. This sensor combines a hybrid fluidic-optronic CMOS (holed retina) that is able to record a specific irradiance pattern scattered by an illuminated particle (scattering signature), while enabling the circulation of particles toward the sensing area. The holed retina is optically coupled with a monolithic, millimeter-sized, refracto-reflective optical system. The latter notably performs an optical pre-processing of signatures, with a very wide field of view of scattering angles. This improves the sensitivity of the sensors, and simplifies image processing. We report the precise design methodology for such a sensor, as well as its fabrication and characterization using calibrated polystyrene beads. Finally, we discuss its ability to characterize particles and its potential for further miniaturization and integration.

APA, Harvard, Vancouver, ISO, and other styles

14

Wang, W. C. "Design of Optical System for Laser Rangefinder." Advanced Materials Research 187 (February 2011): 581–85. http://dx.doi.org/10.4028/www.scientific.net/amr.187.581.

Full text

Abstract:

The principle and classes of grating sensors are analyzed in this paper firstly. To the high-precision requirement of rangefinder for the measurement of high voltage cables, the design method based on grating sensor is proposed. It is realized by installing two grating sensors on the rangefinder platform which are used for outputting the elevation angle and the horizontal angle. The subdivision circuit of system is described in detail by using E-subdivision algorithm. Experiment shows that it can increase the measure precision greatly.

APA, Harvard, Vancouver, ISO, and other styles

15

Okura, Ichiro. "Overview of optical sensors using porphyrins." Journal of Porphyrins and Phthalocyanines 06, no. 04 (April 2002): 268–70. http://dx.doi.org/10.1142/s1088424602000300.

Full text

Abstract:

To meet recent requirement of sensors, new optical sensor technology by molecules of functional chemical compounds as nano-scale sensor probes is developing. In this overview, the background and the concept of optical sensor technology are briefly introduced and a new optical sensing system by triplet-triplet absorption is discussed as an example.

APA, Harvard, Vancouver, ISO, and other styles

16

YOSHIZAWA, Yoshitaka, Takao TSUTAYA, Seiichi NAKAHARA, and Toshio KANEKO. "Development of optical pressure sensor system." Journal of Advanced Science 4, no. 3 (1992): 214–16. http://dx.doi.org/10.2978/jsas.4.214.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Javidi, Bahram, Seung-Hyun Hong, and Osamu Matoba. "Multidimensional optical sensor and imaging system." Applied Optics 45, no. 13 (May 1, 2006): 2986. http://dx.doi.org/10.1364/ao.45.002986.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Raj, Rajnish, Pooja Lohia, and D. K. Dwivedi. "Optical Fibre Sensors for Photonic Applications." Sensor Letters 17, no. 10 (October 1, 2019): 792–99. http://dx.doi.org/10.1166/sl.2019.4152.

Full text

Abstract:

Recent development in optical fiber and numerous advantages of light over electronic system have boosted the utility and demand for optical fibre sensor in modern era. Optical fibre sensor is used to measure the various parameters like temperature, pressure, vibration, rotation etc. Optical fibre sensor offers a wide spectrum of advantage over traditional sensing system in terms of longer lifetime and small in size. Optical fibre has been considered as not only the substitutes of conventional sensors but also the unique solutions in the field of scientific engineering and industrial research. This paper reports the status of optical fibre sensor and its application in detail.

APA, Harvard, Vancouver, ISO, and other styles

19

Fischer, Jakob, Timo Schuster, Christian Wächter, Michael Luber, Juri Vinogradov, Olaf Ziemann, and Rainer Engelbrecht. "Isolated sensor networks for high-voltage environments using a single polymer optical fiber and LEDs for remote powering as well as data transmission." Journal of Sensors and Sensor Systems 7, no. 1 (March 27, 2018): 193–206. http://dx.doi.org/10.5194/jsss-7-193-2018.

Full text

Abstract:

Abstract. Many applications in high voltage or explosive environments require sensors which are electrically isolated from other components of a system. These sensors need remote powering as well as wireless or isolated data transmission links. A possible solution can be based on optically powered optical sensor links. These typically employ four different photonic components: for the data communication a fast LED as a transmitter and a photo diode as a receiver, furthermore for sensor powering a high-power light source and a photonic power converter. Additionally, two optical fibers are required for optical remote powering and the optical data link. In this paper we demonstrate an optically powered optical sensor link using only low-cost high-brightness LEDs and a single polymer optical fiber (POF) for all of these tasks. Coupling efficiencies, power transmission and modulation bandwidths are analyzed for LEDs with different colors. Potentials for many mW of electrical remote powering and Mbit s−1 sensor data links are demonstrated over 10 m of POF. This approach can be used for almost any electronic sensor with moderate power requirements.

APA, Harvard, Vancouver, ISO, and other styles

20

Xu, Cheng, and Zahra Sharif Khodaei. "A Novel Fabry-Pérot Optical Sensor for Guided Wave Signal Acquisition." Sensors 20, no. 6 (March 19, 2020): 1728. http://dx.doi.org/10.3390/s20061728.

Full text

Abstract:

In this paper, a novel hybrid damage detection system is proposed, which utilizes piezoelectric actuators for guided wave excitation and a new fibre optic (FO) sensor based on Fabry-Perot (FP) and Fiber Bragg Grating (FBG). By replacing the FBG sensors with FBG-based FP sensors in the hybrid damage detection system, a higher strain resolution is achieved, which results in higher damage sensitivity and higher reliability in diagnosis. To develop the novel sensor, optimum parameters such as reflectivity, a wavelength spectrum, and a sensor length were chosen carefully through an analytical model of the sensor, which has been validated with experiments. The sensitivity of the new FBG-based FP sensors was compared to FBG sensors to emphasize the superiority of the new sensors in measuring micro-strains. Lastly, the new FBG-based FP sensor was utilized for recording guided waves in a hybrid setup and compared to the conventional FBG hybrid sensor network to demonstrate their improved performance for a structural health monitoring (SHM) application.

APA, Harvard, Vancouver, ISO, and other styles

21

Lamberti, Alfredo, Ben De Pauw, and Steve Vanlanduit. "Development of an Optical Fiber Sensor Interrogation System for Vibration Analysis." Journal of Sensors 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/5204581.

Full text

Abstract:

Since the introduction of dynamic optical fiber sensor interrogation systems on the market it has become possible to perform vibration measurements at frequencies up to a few kHz. Nevertheless, the use of these sensors in vibration analysis has not become a standard practice yet. This is mainly caused by the fact that interrogators are stand-alone systems which focus on strain measurements while other types of signals are also required for vibration analysis (e.g., force signals). In this paper, we present a fiber Bragg grating (FBG) interrogation system that enables accurate strain measurement simultaneously with other signals (e.g., excitation forces). The system is based on a Vertical Cavity Surface Emitting Laser (VCSEL) and can easily be assembled with relatively low-cost off-the-shelf components. Dynamic measurements up to a few tens of kHz with a dynamic precision of around 3 nanostrain per square-root Hz can be performed. We evaluate the proposed system on two measurement examples: a steel beam with FBG sensors glued on top and a composite test specimen with a fiber sensor integrated within the material. We show that in the latter case the results of the interrogation system are superior in quality compared to a state-of-the-art commercially available interrogation system.

APA, Harvard, Vancouver, ISO, and other styles

22

Fernández, Rubén, Josu Amorebieta, Iker García, Gotzon Aldabaldetreku, Joseba Zubia, and Gaizka Durana. "Review of a Custom-Designed Optical Sensing System for Aero-Engine Applications." International Journal of Turbomachinery, Propulsion and Power 6, no. 1 (February 25, 2021): 3. http://dx.doi.org/10.3390/ijtpp6010003.

Full text

Abstract:

Fibre bundle-based reflective optical sensors are good candidates for parameter monitorisation in aero engines. Tip clearance is one of those parameters of great concern that is necessary to monitor. Within this optical technology, the evolution experienced by a custom-designed optical sensor is presented from its first configuration up to the fifth one. The performance of the last configuration is compared with those of other two optical sensors that are also based on a fibre bundle design. The comparison has been carried out in an experimental program in a transonic wind tunnel for aero engines. The proven high resolution and sensitivity of the last configuration of the optical sensor opens up the possibility to detect blade defects, cracks, etc. that could otherwise be hard to track.

APA, Harvard, Vancouver, ISO, and other styles

23

PARK, CHAN JONG, and KWANG YUN WOHN. "FUSION OF THE MAGNETIC AND OPTICAL INFORMATION FOR MOTION CAPTURING." International Journal of Image and Graphics 07, no. 04 (October 2007): 641–62. http://dx.doi.org/10.1142/s0219467807002842.

Full text

Abstract:

We propose a sensor fusion technique for motion capture system. In our system, two kinds of sensors are used for mutual assistance. Six magnetic sensors are attached on the arms and feet for assisting twelve optical markers and six optical markers, which are attached on the arms and feet of a performer, respectively. The optical marker information is not always complete because the optical markers can be hidden due to obstacles. In this case, magnetic sensor information is used to link discontinuous optical marker information. We use a system identification technique for modeling the relation between the two signals of sensor and marker. We determine the best model from the set of candidate models using the canonical system identification technique. In order to show the efficiency of the proposed system, experiments are performed for motion capture data obtained from both the optical and magnetic motion capture system, and the animation results are shown.

APA, Harvard, Vancouver, ISO, and other styles

24

Hazen, John, and L. Scorsone. "Infrared Sensor Calibration Facility." Journal of the IEST 35, no. 1 (January 1, 1992): 33–40. http://dx.doi.org/10.17764/jiet.2.35.1.d536816582691754.

Full text

Abstract:

The Boeing Infrared Sensor (BIRS) Calibration Facility represents a major capital investment by The Boeing Company in optical and infrared technology. The facility was designed and built for calibrating and testing new generation large aperture long wave infrared (LWIR) sensors, seekers, and related technologies. The capability exists to perform both radiometric and goniometric calibrations of large infrared sensors under simulated environmental operating conditions. The system is presently configured for endoatmospheric calibrations with a uniform background field that can be set to simulate the expected mission background levels. During calibration, the sensor under test is also exposed to expected mission temperatures and pressures within the test chamber. The facility could be converted for exoatmospheric testing. The first major test runs in the facility were completed during 1989 with very satisfactory results. This paper will describe system configuration and hardware elements, and will address the modifications made to date. Pitt-Des Moines. Inc. (PDM) of Pittsburgh, Pennsylvania, was the contractor for the turnkey design and construction of the test chambers and thermal vacuum systems. Hughes Danbury Optical Systems (formerly Perkin Elmer Optical Systems) was the hardware supplier for the optical hardware. The Boeing Company performed all optical assembly, integration, testing, and alignment on-site.

APA, Harvard, Vancouver, ISO, and other styles

25

Li, Nan, and Cun Fu He. "Capacitive Sensor Design for an Automatic Car-Wiper System." Advanced Materials Research 211-212 (February 2011): 798–802. http://dx.doi.org/10.4028/www.scientific.net/amr.211-212.798.

Full text

Abstract:

A structure of capacitance sensor used for an automatic car-wiper system is presented. It aims to develop a low-cost sensor with high sensitivity and robustness. Firstly, two kinds of sensing technique based on optical and piezoelectric sensors for an automatic car-wiper system are introduced respectively. Then, three types of capacitance sensors of different shapes are designed. The parameters which affecting the sensor signal strength and measurement sensitivity are discussed. Thirdly, the electric field distributions of the sensors are simulated, and the fringe capacitance of the sensors are measured and analyzed. Finally, the optimum excitation frequency of designed sensor is determined, and the sensor noise is discussed in this paper. The experimental results indicate the validity and importance of the capacitance-based sensing technique which can be used for liquid detection on windshield of vehicles.

APA, Harvard, Vancouver, ISO, and other styles

26

En, De, Chang Sheng Zhou, Huang He Wei, Na Na Wei, and Xiao Long Shi. "Research of MOEMS Pressure Sensor." Applied Mechanics and Materials 273 (January 2013): 524–27. http://dx.doi.org/10.4028/www.scientific.net/amm.273.524.

Full text

Abstract:

In recent years, with the development of optical communication by leaps and bounds, promote the Micro-opto-electro-mechanical system (MOEMS) development. As a new technology, the MOEMS have been widely used in optical communication, optical switching, data storage, optical sensing and etc.. Compared with the traditional pressure sensors, the optical pressure sensor based on MOEMS has some unique advantages. In this paper, the structures, operation principles and fabrication processes of various MOEMS pressure sensors are described mainly. Finally, the structure and Key technology of a MOEMS pressure sensor array is presented in brief.

APA, Harvard, Vancouver, ISO, and other styles

27

Senkans, Ugis, Janis Braunfelds, Ilya Lyashuk, Jurgis Porins, Sandis Spolitis, and Vjaceslavs Bobrovs. "Research on FBG-Based Sensor Networks and Their Coexistence with Fiber Optical Transmission Systems." Journal of Sensors 2019 (November 6, 2019): 1–13. http://dx.doi.org/10.1155/2019/6459387.

Full text

Abstract:

Market forecasts and trends for the usage of fiber optical sensors confirm that demand for them will continue to increase in the near future. This article focuses on the research of fiber Bragg grating (FBG) sensor network, their applications in IoT and structural health monitoring (SHM), and especially their coexistence with existing fiber optical communication system infrastructure. Firstly, the spectrum of available commercial optical FBG temperature sensor was experimentally measured and amplitude-frequency response data was acquired to further develop the simulation model in the environment of RSoft OptSim software. The simulation model included optical sensor network, which is combined with 8-channel intensity-modulated wavelength division multiplexed (WDM) fiber optical data transmission system, where one shared 20 km long ITU-TG.652 single-mode optical fiber was used for transmission of both sensor and data signals. Secondly, research on a minimal allowable channel spacing between sensors’ channels was investigated by using MathWorks MATLAB software, and a new effective and more precise determination algorithm of the exact center of the sensor signal’s peak was proposed. Finally, we experimentally show successfully operating coexistence concept of the spectrum-sliced fiber optical transmission system with embedded scalable FBG sensor network over one shared optical fiber, where the whole system is feed by only one broadband light source.

APA, Harvard, Vancouver, ISO, and other styles

28

Shim, Joonhwan. "Liquid level measurement system using capacitive sensor and optical sensor." Journal of the Korean Society of Marine Engineering 37, no. 7 (November 30, 2013): 778–83. http://dx.doi.org/10.5916/jkosme.2013.37.7.778.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Wu, Chuan, Jian Feng Lu, and Bai Gen He. "Design of Optical Electronic Watch System Based on Multi-Sensor." Advanced Materials Research 753-755 (August 2013): 2232–34. http://dx.doi.org/10.4028/www.scientific.net/amr.753-755.2232.

Full text

Abstract:

Optical electronic monitoring system is widely used in battlefield assessment, forest fire preventing, road monitoring, etc. This paper proposes an optical electronic monitoring system based on multiple-sensor. Multi-sensors use common optical route in this the system. It means to get the same scene in the same time. In order to extend the transmission distance, reducing the complexity of the wiring, the system design a transform module. Through the transform module, the system transforms CamerLink standard signal to network package and uses network transmission image.

APA, Harvard, Vancouver, ISO, and other styles

30

Volkov, O. A., A. V. Demin, and K. V. Konstantinov. "AN OPTICAL SYSTEM OF A SENSOR FOR MEASURING THE METEOROLOGICAL OPTICAL RANGE." Computer Optics 42, no. 1 (March 30, 2018): 67–71. http://dx.doi.org/10.18287/2412-6179-2018-42-1-67-71.

Full text

Abstract:

Principles of constructing an optical sensor for measuring a meteorological visibility range are considered. A new relationship for the visibility range determination is obtained. An optical scheme of the meteorological visibility range sensor is described and characteristics of the new sensor are presented.

APA, Harvard, Vancouver, ISO, and other styles

31

Floridia, Claudio, Joao Batista Rosolem, João Paulo Vicentini Fracarolli, Fábio Renato Bassan, Rivael Strobel Penze, Larissa Maria Pereira, and Maria Angélica Carmona da Motta Resende. "Evaluation of Environmental Influences on a Multi-Point Optical Fiber Methane Leak Monitoring System." Remote Sensing 11, no. 10 (May 27, 2019): 1249. http://dx.doi.org/10.3390/rs11101249.

Full text

Abstract:

A novel system to monitor methane fugitive emissions was developed using passive optical sensors to attend to the natural gas production and transportation industry. The system is based on optical time domain reflectometry and direct optical absorption spectroscopy. The system was tested in a gas compressor station for four months. The system was capable to measure methane concentration at two points showing its correlation with meteorological data, specially wind velocity and local temperature. Methane concentrations varied from 2.5% to 15% in the first monitored point by sensor 1, and from 5% to 30%, in the second point with sensor 2. Both sensors exhibited a moderate negative correlation with wind velocity with a mean Pearson coefficient of −0.61, despite the external cap designed to avoid the influence of wind. Sensor 2 had a modification to its external package that reduced this mean correlation coefficient to −0.30, considered to be weak to negligible. Regarding temperature, a moderate mean correlation of −0.59 was verified for sensor 1 and zero mean correlation was found for sensor 2. Based on these results the system was proven to be robust for installation in gas transportation or processing facilities.

APA, Harvard, Vancouver, ISO, and other styles

32

Feinholz, Michael E., Stephanie J. Flora, Mark A. Yarbrough, Keith R. Lykke, Steven W. Brown, B. Carol Johnson, and Dennis K. Clark. "Stray Light Correction of the Marine Optical System." Journal of Atmospheric and Oceanic Technology 26, no. 1 (January 1, 2009): 57–73. http://dx.doi.org/10.1175/2008jtecho597.1.

Full text

Abstract:

Abstract The Marine Optical System is a spectrograph-based sensor used on the Marine Optical Buoy for the vicarious calibration of ocean color satellite sensors. It is also deployed from ships in instruments used to develop bio-optical algorithms that relate the optical properties of the ocean to its biological content. In this work, an algorithm is applied to correct the response of the Marine Optical System for scattered, or improperly imaged, light in the system. The algorithm, based on the measured response of the system to a series of monochromatic excitation sources, reduces the effects of scattered light on the measured source by one to two orders of magnitude. Implications for the vicarious calibration of satellite ocean color sensors and the development of bio-optical algorithms are described. The algorithm is a one-dimensional point spread correction algorithm, generally applicable to nonimaging sensors, but can in principle be extended to higher dimensions for imaging systems.

APA, Harvard, Vancouver, ISO, and other styles

33

Li, Yan Sheng, Ting Yuan Nie, and Chuan Wang Song. "A Proposal of Fiber Sensing System Using Low Reflectivity FBG." Key Engineering Materials 500 (January 2012): 743–47. http://dx.doi.org/10.4028/www.scientific.net/kem.500.743.

Full text

Abstract:

This paper proposes multipoint optical fiber sensing system based on fiber Bragg grating (FBG) sensor array. The low reflectivity FBG sensors having the same Bragg wavelength are connected cascaded in the same fiber line as the sensing elements of optical fiber sensing system. This can increase the monitoring points and reduce manufacturing costs of FBG sensor. To verify the effectiveness, the system simulator based on equivalent circuit model by microwave technology was developed. Simulation result shows that though multi-reflections can be caused by FBG sensors with the same Bragg wavelength connected cascaded in the same line, the effect may become weak as reflectivity of FBG sensors are reduced to 0.02.

APA, Harvard, Vancouver, ISO, and other styles

34

Ursel, Tomasz, and Michał Olinski. "Displacement Estimation Based on Optical and Inertial Sensor Fusion." Sensors 21, no. 4 (February 17, 2021): 1390. http://dx.doi.org/10.3390/s21041390.

Full text

Abstract:

This article aims to develop a system capable of estimating the displacement of a moving object with the usage of a relatively cheap and easy to apply sensors. There is a growing need for such systems, not only for robots, but also, for instance, pedestrian navigation. In this paper, the theory for this idea, including data postprocessing algorithms for a MEMS accelerometer and an optical flow sensor (OFS), as well as the developed complementary filter applied for sensor fusion, are presented. In addition, a vital part of the accelerometer’s algorithm, the zero velocity states detection, is implemented. It is based on analysis of the acceleration’s signal and further application of acceleration symmetrization, greatly improving the obtained displacement. A test stand with a linear guide and motor enabling imposing a specified linear motion is built. The results of both sensors’ testing suggest that the displacement estimated by each of them is highly correct. Fusion of the sensors’ data gives even better outcomes, especially in cases with external disturbance of OFS. The comparative evaluation of estimated linear displacements, in each case related to encoder data, confirms the algorithms’ operation correctness and proves the chosen sensors’ usefulness in the development of a linear displacement measuring system.

APA, Harvard, Vancouver, ISO, and other styles

35

Kondratov, V. "Metrological Support for Wireless Sensor Systems." Cybernetics and Computer Technologies, no. 1 (March 31, 2020): 83–92. http://dx.doi.org/10.34229/2707-451x.20.1.9.

Full text

Abstract:

The paper identifies twelve problems of metrological reliability of wireless sensor systems that require their solution. The most urgent is the problem of determining the main parameters of the metrological reliability of wireless sensor systems. It is closely related to solving the problem of self-calibration of optical smart sensors that are part of the smart nodes of the system. The task of self-calibration of smart sensors is solved when three basic conditions are met: 1) when creating and using structurally redundant optical sensors designed to implement methods of redundant measurements; 2) when developing LEDs or other highly stable sources of optical radiation, including those with controlled parameters, for any given spectral range of wavelengths; 3) when creating in micro-performance filters on a priori given range of the spectrum of optical sines. The article describes two methods of metrological support for BSS smart sensors, based on the introduction of information redundancy by conducting three clock cycles of measuring physical quantity with a smart sensor, followed by processing the data using an a priori derived algorithm. The disadvantages and advantages of the methods are shown. It is stated that the use of the theory of excess measurements is the only correct way to solve the problem of self-calibration of sensors and measuring instruments. Given the harsh operating conditions of optical smart sensors, it is preferable to manufacture them using high technology. Today, in Ukraine, no one is engaged in a practical solution to the problems of metrological reliability of wireless sensor systems and the solution of the problems of self-calibration of smart sensors.

APA, Harvard, Vancouver, ISO, and other styles

36

Deepa, N., and A. Balaji Ganesh. "Optical Sensor for Indian Siddha Diagnosis System." Procedia Engineering 38 (2012): 1126–31. http://dx.doi.org/10.1016/j.proeng.2012.06.142.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Sano, Yasukazu, Hideyuki Tanaka, and Taichi Tanigawa. "Optical Occupant Position Sensor for Airbag System." IEEJ Transactions on Sensors and Micromachines 119, no. 1 (1999): 1–6. http://dx.doi.org/10.1541/ieejsmas.119.1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Soroush, Ali, Mohammad Akbar, and Farzam Farahmand. "How to Synchronize and Register an Optical-Inertial Tracking System." Applied Mechanics and Materials 332 (July 2013): 130–36. http://dx.doi.org/10.4028/www.scientific.net/amm.332.130.

Full text

Abstract:

Multi-sensor tracking is widely used for augmentation of tracking accuracy using data fusion. A basic requirement for such applications is the real time temporal synchronization and spatial registration of two sensory data. In this study a new method for time and space coordination of two tracking sensor measurements has been presented. For spatial registration we used a body coordinate system and then applied the effect of the level arm. The time synchronization was done based on least mean square (LMS) error method. This method was implemented to synchronize the position and orientation of an object using Inertial ( IMU) and Optical (Optotrak) tracking systems. The results of synchronized data were validated with measurements of Optical tracking system and the mean error of synchronized Euler angles, were less than 0.28 degree.

APA, Harvard, Vancouver, ISO, and other styles

39

Yoo, Jung Cheol, Chang Doo Kee, and Il Kwon Oh. "Development of Ultrasonic Optical Fiber Hydrogen Sensor." Advances in Science and Technology 65 (October 2010): 163–67. http://dx.doi.org/10.4028/www.scientific.net/ast.65.163.

Full text

Abstract:

In this study, an ultrasonic optical fiber hydrogen sensor was newly developed for monitoring and detecting hydrogen leakages. Previously, we developed a pulse-echo sensor system for health monitoring system. Ultrasonic wave, generated from a piezoelectric actuator, is guided and propagated through the optical fiber and subsequently sensed by a piezoelectric sensor in the pulse-echo sensor system. For the detection of hydrogen, the optical fiber was coated with palladium particles, which expanded on exposure to hydrogen. Palladium was used, because it adsorbs hydrogen gas and swell slightly to form palladium hydride with exposure to hydrogen. The change in palladium dimensions affects the wave propagation impedance of optical fiber for detecting the hydrogen gas, and this method has been applied to the pulse-echo sensor systems. Our results showed that the ultrasonic-optical fiber hydrogen sensor can be successfully employed for hydrogen detecting system.

APA, Harvard, Vancouver, ISO, and other styles

40

Lee, Kang-Ho, Yeong-Eun Kwon, Hyukjin Lee, Yongkoo Lee, Joonho Seo, Ohwon Kwon, Shin-Won Kang, and Dongkyu Lee. "Active Body Pressure Relief System with Time-of-Flight Optical Pressure Sensors for Pressure Ulcer Prevention." Sensors 19, no. 18 (September 6, 2019): 3862. http://dx.doi.org/10.3390/s19183862.

Full text

Abstract:

A body pressure relief system was newly developed with optical pressure sensors for pressure ulcer prevention. Unlike a conventional alternating pressure air mattress (APAM), this system automatically regulates air flow into a body supporting mattress with adaptive inflation (or deflation) duration in response to the pressure level in order to reduce skin stress due to prolonged high pressures. The system continuously quantifies the body pressure distribution using time-of-flight (ToF) optical sensors. The proposed pressure sensor, a ToF optical sensor in the air-filled cell, measures changes in surface height of mattress when pressed under body weight, thereby indirectly indicating the interface pressure. Non-contact measurement of optical sensor usually improves the durability and repeatability of the system. The pressure sensor was successfully identified the 4 different-predefined postures, and quantitatively measured the body pressure distribution of them. Duty cycle of switches in solenoid valves was adjusted to 0–50% for pressure relief, which shows that the interface pressure was lower than 32 mmHg for pressure ulcer prevention.

APA, Harvard, Vancouver, ISO, and other styles

41

Wang, Qilong, Yu Zhang, Weichao Shi, and Meng Nie. "Laser Ranging-Assisted Binocular Visual Sensor Tracking System." Sensors 20, no. 3 (January 27, 2020): 688. http://dx.doi.org/10.3390/s20030688.

Full text

Abstract:

Aimed at improving the low measurement accuracy of the binocular vision sensor along the optical axis in the process of target tracking, we proposed a method for auxiliary correction using a laser-ranging sensor in this paper. In the process of system measurement, limited to the mechanical performance of the two-dimensional turntable, the measurement value of a laser-ranging sensor is lagged. In this paper, the lag information is updated directly to solve the time delay. Moreover, in order to give full play to the advantages of binocular vision sensors and laser-ranging sensors in target tracking, federated filtering is used to improve the information utilization and measurement accuracy and to solve the estimated correlation. The experimental results show that the real-time and measurement accuracy of the laser ranging-assisted binocular visual-tracking system is improved by the direct update algorithm and the federal filtering algorithm. The results of this paper are significant for binocular vision sensors and laser-ranging sensors in engineering applications involving target tracking systems.

APA, Harvard, Vancouver, ISO, and other styles

42

Li, Li Fu. "Space Optical Remote Sensor of the CAE Thermal Control Index Calculation Method." Advanced Materials Research 308-310 (August 2011): 2328–33. http://dx.doi.org/10.4028/www.scientific.net/amr.308-310.2328.

Full text

Abstract:

The thermal control indicators CAE methods of Space optical remote sensor are analyzed in the presented work. We sat up a thermal optical analysis model for space optical remote sensor. By assuming fully covered by in-orbit temperature load, and using the finite element method for thermal deformation analysis, we obtained the optical remote sensor surface deformation and displacement under various thermal loading. Using ZERNIKE polynomial, wave was fitted to obtain ZERNIKE polynomial coefficients which were incorporated into the optical system design. Using CODE V optical calculation software, heat-ray machines under elastic deformation of the system point spread function, transfer function (MTF), wave front differential (WFE) etc. were calculated. Image quality changes of remote sensors are discussed in variety assumed cases such as temperature loads of quality change. By repeated iteration, critical value of temperature fields meeting the design requirements are obtained for the optical system. Optical indicators were converged to the temperature field indicator, then reasonable indicators of thermal control for remote sensors were obtained. For the thermal control design, this method provided a reliable basis for design.

APA, Harvard, Vancouver, ISO, and other styles

43

Xu, Shaoyi, Qiang Peng, Chuansheng Li, Bo Liang, Junwen Sun, Fangfang Xing, Hongyu Xue, and Ming Li. "Optical Fiber Current Sensors Based on FBG and Magnetostrictive Composite Materials." Applied Sciences 11, no. 1 (December 26, 2020): 161. http://dx.doi.org/10.3390/app11010161.

Full text

Abstract:

Optical fiber current sensors are widely used in the online monitoring of a new generation power system because of their high electrical insulation, wide dynamic range, and strong anti-electromagnetic interference ability. Current sensors, based on fiber Bragg grating (FBG) and giant magnetostrictive material, have the advantages of high reliability of FBG and high magnetostrictive coefficient of giant magnetostrictive material, which can meet the monitoring requirements of digital power systems. However, giant magnetostrictive materials are expensive, fragile, and difficult to mold, so giant magnetostrictive composite materials have replaced giant magnetostrictive materials as the sensitive elements of sensors. High sensitivity, high precision, wide working range, low response time, and low-cost optical fiber current sensors based on magnetostrictive composites have become a research hotspot. In this paper, the working principle of the sensor, the structure of the sensor, and the improvement of magnetostrictive composite materials are mainly discussed. At the same time, this paper points out improvements for the sensor.

APA, Harvard, Vancouver, ISO, and other styles

44

Penso, Camila M., João L. Rocha, Marcos S. Martins, Paulo J. Sousa, Vânia C. Pinto, Graça Minas, Maria M. Silva, and Luís M. Goncalves. "PtOEP–PDMS-Based Optical Oxygen Sensor." Sensors 21, no. 16 (August 21, 2021): 5645. http://dx.doi.org/10.3390/s21165645.

Full text

Abstract:

The advanced and widespread use of microfluidic devices, which are usually fabricated in polydimethylsiloxane (PDMS), requires the integration of many sensors, always compatible with microfluidic fabrication processes. Moreover, current limitations of the existing optical and electrochemical oxygen sensors regarding long-term stability due to sensor degradation, biofouling, fabrication processes and cost have led to the development of new approaches. Thus, this manuscript reports the development, fabrication and characterization of a low-cost and highly sensitive dissolved oxygen optical sensor based on a membrane of PDMS doped with platinum octaethylporphyrin (PtOEP) film, fabricated using standard microfluidic materials and processes. The excellent mechanical and chemical properties (high permeability to oxygen, anti-biofouling characteristics) of PDMS result in membranes with superior sensitivity compared with other matrix materials. The wide use of PtOEP in sensing applications, due to its advantage of being easily synthesized using microtechnologies, its strong phosphorescence at room temperature with a quantum yield close to 50%, its excellent Strokes Shift as well as its relatively long lifetime (75 µs), provide the suitable conditions for the development of a miniaturized luminescence optical oxygen sensor allowing long-term applications. The influence of the PDMS film thickness (0.1–2.5 mm) and the PtOEP concentration (363, 545, 727 ppm) in luminescent properties are presented. This enables to achieve low detection levels in a gas media range from 0.5% up to 20%, and in liquid media from 0.5 mg/L up to 3.3 mg/L at 1 atm, 25 °C. As a result, we propose a simple and cost-effective system based on a LED membrane photodiode system to detect low oxygen concentrations for in situ applications.

APA, Harvard, Vancouver, ISO, and other styles

45

Zheng, Yani, Gaurav Dhiman, Ashutosh Sharma, Amit Sharma, and Mohd Asif Shah. "An IoT-Based Water Level Detection System Enabling Fuzzy Logic Control and Optical Fiber Sensor." Security and Communication Networks 2021 (August 27, 2021): 1–11. http://dx.doi.org/10.1155/2021/4229013.

Full text

Abstract:

The usage of wireless sensors has become widespread for the collection of data for various Internet of Things (IoT) products. Specific wireless sensors use optical fiber technology as transmission media and lightwave signals as carriers, showing the advantages of antielectromagnetic interference, high sensitivity, and strong reliability. Hence, their application in IoT systems becomes a research hotspot. In this article, multiple optical fiber sensors are constructed as an IoT detection system, and a Transmission Control Protocol (TCP)/Internet Protocol (IP) communication stack is used for the sensor module. Furthermore, design of gateway module, data server, and monitoring module is established in order to run the data server in the Windows system and communicate across the network segments. Furthermore, the optical fiber sensor is connected to the development board with WiFi, meanwhile considering the optical fiber wireless network’s congestion problem. The fuzzy logic concept is introduced from the perspective of cache occupancy, and a fiber sensor’s network congestion control algorithm is proposed. In the experiment, the IoT detection system with multiple optical fiber sensors is used for water level detection, and the sensor’s real-time data detected by the User Interface (UI) are consistent with the feedback results. The proposed method is also compared with the SenTCP algorithm and the CODA algorithm, and it was observed that the proposed network congestion control algorithm based on the fuzzy logic can improve network throughput and reduce the network data packet loss.

APA, Harvard, Vancouver, ISO, and other styles

46

Zhou, Feichi, Jiewei Chen, Xiaoming Tao, Xinran Wang, and Yang Chai. "2D Materials Based Optoelectronic Memory: Convergence of Electronic Memory and Optical Sensor." Research 2019 (August 21, 2019): 1–17. http://dx.doi.org/10.34133/2019/9490413.

Full text

Abstract:

The continuous development of electron devices towards the trend of “More than Moore” requires functional diversification that can collect data (sensors) and store (memories) and process (computing units) information. Considering the large occupation proportion of image data in both data center and edge devices, a device integration with optical sensing and data storage and processing is highly demanded for future energy-efficient and miniaturized electronic system. Two-dimensional (2D) materials and their heterostructures have exhibited broadband photoresponse and high photoresponsivity in the configuration of optical sensors and showed fast switching speed, multi-bit data storage, and large ON/OFF ratio in memory devices. In addition, its ultrathin body thickness and transfer process at low temperature allow 2D materials to be heterogeneously integrated with other existing materials system. In this paper, we overview the state-of-the-art optoelectronic random-access memories (ORAMs) based on 2D materials, as well as ORAM synaptic devices and their applications in neural network and image processing. The ORAM devices potentially enable direct storage/processing of sensory data from external environment. We also provide perspectives on possible directions of other neuromorphic sensor design (e.g., auditory and olfactory) based on 2D materials towards the future smart electronic systems for artificial intelligence.

APA, Harvard, Vancouver, ISO, and other styles

47

Mao, Yao, Wei Ren, Yong Luo, and Zhijun Li. "Optimal Design Based on Closed-Loop Fusion for Velocity Bandwidth Expansion of Optical Target Tracking System." Sensors 19, no. 1 (January 2, 2019): 133. http://dx.doi.org/10.3390/s19010133.

Full text

Abstract:

Micro-electro-mechanical system (MEMS) gyro is one of the extensively used inertia sensors in the field of optical target tracking (OTT). However, velocity closed-loop bandwidth of the OTT system is limited due to the resonance and measurement range issues of MEMS gyro. In this paper, the generalized sensor fusion framework, named the closed-loop fusion (CLF), is analyzed, and the optimal design principle of filter is proposed in detail in order to improve measurement of the bandwidth of MEMS gyro by integrating information of MEMS accelerometers. The fusion error optimization problem, which is the core issue of fusion design, can be solved better through the feedback compensation law of CLF framework and fusion filter optimal design. Differently from conventional methods, the fusion filter of CLF can be simply and accurately designed, and the determination of superposition of fusion information can also be effectively avoided. To show the validity of the proposed method, both sensor fusion simulations and closed-loop experiments of optical target tracking system have yielded excellent results.

APA, Harvard, Vancouver, ISO, and other styles

48

Reed, G. T., M. Hadjiprocopiou, A. Möller, H. Garden, A. Thorne, and L. Hollaway. "Low Cost Dynamic Optical Strain Measurements in Glass Reinforced Polymer." Advanced Composites Letters 3, no. 3 (May 1994): 096369359400300. http://dx.doi.org/10.1177/096369359400300301.

Full text

Abstract:

The combination of sensors and structural components to create “Smart Structures” or “Smart Skins” represents a new, fast developing branch of engineering. The monitoring of such systems will require accurate and fast strain measurements. Optical sensing techniques are receiving considerable attention for monitoring of such systems. In this work an optical fibre sensor has been embedded with the protective coating on, in glass reinforced polymer (GRP) coupons, to perform strain measurements. We show that the system can be used for measurements up to 2000με. The sensor was made using only commercially available, low cost components. The optical measurements show good agreement with conventional strain gauge measurements.

APA, Harvard, Vancouver, ISO, and other styles

49

Shan, Ning. "Design and Experiment Research of a Non-Contact Optical Fiber F-P Ultrasound Sensor for Detecting Surface Defects." Applied Mechanics and Materials 34-35 (October 2010): 322–26. http://dx.doi.org/10.4028/www.scientific.net/amm.34-35.322.

Full text

Abstract:

Laser ultrasound technology has many advantages such as being non-contact, nondestructive, fast, accurate and low cost. Therefore it is usually used as an effective way to detect and characterize small surface or subsurface breaking cracks. The optical fiber F-P sensor is adapted to laser ultrasound detection field because it can detect ultrasound signals non-contact. But the optical fiber F-P sensor deviates from working point easily because of machining error and external factors in practical applications. It leads to output signal attenuation and the decreasing of signal noise ratio. On this problem, an optical fiber F-P sensing system based on two wavelength quadrature-shifted demodulation technique is designed. The mathematical model of sensing system is established. Differential Evolution Algorithm is introduced to establish the optimal model of sensing system for the first time. The structure of sensing system is optimized designed. The non-contact laser ultrasound experimental devices based on optical fiber F-P senor are established for detecting surface defects. The experimental results show this sensor can detect surface defects effectively. It has higher sensitivity and larger signal-to-noise ratio.

APA, Harvard, Vancouver, ISO, and other styles

50

Wang, Yanli, Mi Wang, and Ying Zhu. "On-Orbit Calibration of Installation Parameter of Multiple Star Sensors System for Optical Remote Sensing Satellite with Ground Control Points." Remote Sensing 12, no. 7 (March 25, 2020): 1055. http://dx.doi.org/10.3390/rs12071055.

Full text

Abstract:

Owing to the vibrations and thermal shocks that arise during the launch and orbit penetration process, the on-orbit installation parameters of multiple star sensors are different from the on-ground measured parameters, causing inconsistencies in the attitude determinations from different combination modes and seriously affecting the geometric accuracy of high-resolution optical remote sensing images. This study presents an on-orbit calibration approach for the installation parameters of a multiple star sensors system using ground control points (GCPs). Based on the on-ground installation parameters of the optical axes of conventional star sensors, a fiducial coordinate system is proposed as the calibration coordinate system. The installation parameters of the conventional star sensors are calibrated using the statistical characteristics of angles between axes of the star sensor and three fiducial vectors in the J2000 celestial coordinate system. Based on the GCPs, the relative fiducial parameters are calculated, and the installation parameter of unconventional star sensor is then calibrated with the relative fiducial parameters and statistical characteristics of angles. It can be used for high-resolution optical remote sensing satellite measuring with only two star sensors to unify the fiducial coordinate system. The proposed method is tested using simulated data and on-orbit measurement data. The results demonstrate that the proposed method can calibrate the optical axis of the star sensor without the restriction of the accuracy of horizontal axis. Moreover, the star sensor with a large installation angle error can be calibrated well using the proposed approach. The results of attitude determinations from different star sensor combination modes are consistent, and the geometric accuracy of the remote sensing images is significantly improved.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Optical sensor system'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles