Статті в журналах: "Bending strain measurement"

1

Li, Rui, Zhensheng Wang, and Pengchao Chen. "Development the method of pipeline bending strain measurement based on microelectromechanical systems inertial measurement unit." Science Progress 103, no. 2 (April 2020): 003685042092523. http://dx.doi.org/10.1177/0036850420925231.

Повний текст джерела

Анотація:

With the development of pipeline construction, the additional stress and strain becomes the key factor to induce the damage for oil and gas pipeline. The in-line inspection of pipeline bending strain which is based on high-end tactical-grade inertial measurement unit has become routine practice for the oil and gas pipelines over recent years. However, these accurate inertial measurement units are large size and high cost limit to use in small diameter pipelines of bending strain inspection. Microelectromechanical systems–based inertial navigation has been applied to mapping the centerline of the small size pipeline, and the accurate trajectory and attitude information become key factors to calculate the bending strain of pipelines. This article proposed a method not only to calculate the pipeline bending strain but also to improve the accuracy for the bending strain based on the wavelet analysis. Tests show that this method can be effectively used in the calculation and optimization of the bending strain, and it will increase the accuracy to within 19.1% of the actual bending strain.

Стилі APA, Harvard, Vancouver, ISO та ін.

2

Ridge, I. M. L., J. Zheng, and C. R. Chaplin. "Measurement of cyclic bending strains in steel wire rope." Journal of Strain Analysis for Engineering Design 35, no. 6 (August 1, 2000): 545–58. http://dx.doi.org/10.1243/0309324001514288.

Повний текст джерела

Анотація:

This paper reports strain gauge measurements of cyclic bending strain in the wires of a six-strand right-handed Lang's lay steel wire rope running on and off a pulley. The paper describes the measurement procedures and presents the results for the two tests conducted which had different gauge configurations along and around the sample. It was found that the strain waveforms observed had some similarities with those reported elsewhere and the magnitudes of strains matched theoretical predictions. However, in contrast with behaviour reported for fluctuating tension, the initial differences between and along wires rapidly attenuated. This observation helps to explain reported similarities in bending fatigue performance of ropes from different sources which contrasts with the very significant differences in characteristics found in tensile fatigue. The dependence of wire strain amplitude on rope bending deformation further contrasts with tensile fatigue in which wire strain range is dependent on the local sharing of axial load.

Стилі APA, Harvard, Vancouver, ISO та ін.

3

Liu, Shucong, Dezhi Zheng, Tianhao Wang, Mengxi Dai, Rui Li, and Qingshan Feng. "A novel algorithm for pipeline displacement and bending strain of in-line inspection based on inertia measurement technology." Advances in Mechanical Engineering 10, no. 12 (December 2018): 168781401881675. http://dx.doi.org/10.1177/1687814018816755.

Повний текст джерела

Анотація:

The in-line inspection tool with Inertial Measurement Unit tool is becoming a routine and important practice for many pipeline companies and is effective for whole-line bending strain measurement. However, the measurements of Inertial Measurement Unit tool are always affected by noises and errors, which are caused by inherent inaccuracies and deficiencies of the experimental techniques and measuring devices. For the calculations of the bending strain, the results are very sensitive to the noises and errors. A filtering algorithm based on cubic spline interpolation was proposed for Inertial Measurement Unit data processing to eliminate noises and errors for bending strain, and the effectiveness is validated through the pipeline field test. The results showed that the average pipeline displacement deviation declined 13.82% in the three tests, and the bending strain error reduced from 0.037% to 0.014%. The proposed method effectively improves the inspection accuracy and provides an effective method for pipeline displacement and strain inspection, which ensures the safe operation of the pipeline.

Стилі APA, Harvard, Vancouver, ISO та ін.

4

Panich, Sansot. "Bending Limit Curves in Sheet Metal Bending Evaluation." Key Engineering Materials 751 (August 2017): 180–85. http://dx.doi.org/10.4028/www.scientific.net/kem.751.180.

Повний текст джерела

Анотація:

Bending and hemming process are used in automotive industries for assembling the car body panel.The main failure mechanism under bending loads is the intercrystalline fracture. This is due to the fact that the Forming Limit Curve (FLC) describes first occurrence of membrane instability and no material failure in consequence of an intercrystalline fracture at bending.The FLC fails to predict the formability in hemming processes since difference in failure mechanism. A new failure criterion, the so-called Bending Limit Curve (BLC) has been developed. In this work, the left hand side BLCs are experimentally determined for Advanced High Strength Steel grade DP1000, Stainless Steel grade SUS430 and Deep Drawing Steel grade SPCC having a thickness of 1.0 mm. The influence of various bending radii and level of pre-strain on the bending strains are investigated and discussed by using the Three Point Bending Test. Bendability of investigated materials are evaluated by using optical strain measurement system GOM-Aramis to determine maximal achievable bending strain on the specimens. The developed left hand side BLCs were found to be higher level than conventional FLCs. The bigger bending radius established lower bending limit strain. The higher bending strain was obtained from the higher pre strain level.

Стилі APA, Harvard, Vancouver, ISO та ін.

5

Socha, Bernard J., Edward T. Bednarz, and Wei-Dong Zhu. "A combined loading transducer for calculating the bending moment and torque in a slender circular beam using the minimum numbers of strain gauges, strain grids, and measurement channels." International Journal of Distributed Sensor Networks 16, no. 6 (June 2020): 155014772092177. http://dx.doi.org/10.1177/1550147720921774.

Повний текст джерела

Анотація:

The purpose of this work is to develop a new methodology that uses the minimum numbers of strain gauges, strain grids, and measurement channels to calculate the bending moment and torque in a slender circular beam under combined loading from measured strains in it. In general, each independent variable requires a minimum of one independent measurement. Two grids of a single-rosette strain gauge located at 45° and −45° from the longitudinal axis of the beam are used in conjunction with two measurement channels to gather all measurements and form a combined loading transducer. A theoretical set of equations of the new methodology is developed to minimize numbers of strain grids and measurement channels, and an experimental configuration was tested in a variety of scenarios. Calibration factors were independently developed for the bending moment and torque of the beam by separately loading it in their respective directions. These calibration factors were applied to different combined loading scenarios, where errors were found to be on average 1.6% for moment comparison and 6.7% for torque comparison.

Стилі APA, Harvard, Vancouver, ISO та ін.

6

Li, Rui, Maolin Cai, Yan Shi, Qingshan Feng, Shucong Liu, and Xiaoming Zhao. "Pipeline Bending Strain Measurement and Compensation Technology Based on Wavelet Neural Network." Journal of Sensors 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/8363242.

Повний текст джерела

Анотація:

The bending strain of long distance oil and gas pipelines may lead to instability of the pipeline and failure of materials, which seriously deteriorates the transportation security of oil and gas. To locate the position of the bending strain for maintenance, an Inertial Measurement Unit (IMU) is usually adopted in a Pipeline Inspection Gauge (PIG). The attitude data of the IMU is usually acquired to calculate the bending strain in the pipe. However, because of the vibrations in the pipeline and other system noises, the resulting bending strain calculations may be incorrect. To improve the measurement precision, a method, based on wavelet neural network, was proposed. To test the proposed method experimentally, a PIG with the proposed method is used to detect a straight pipeline. It can be obtained that the proposed method has a better repeatability and convergence than the original method. Furthermore, the new method is more accurate than the original method and the accuracy of bending strain is raised by about 23% compared to original method. This paper provides a novel method for precisely inspecting bending strain of long distance oil and gas pipelines and lays a foundation for improving the precision of inspection of bending strain of long distance oil and gas pipelines.

Стилі APA, Harvard, Vancouver, ISO та ін.

7

Yu, Feng, and Michael T. Hendry. "A new strain gauge configuration on the rail web to decouple the wheel–rail lateral contact force from wayside measurement." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 233, no. 9 (January 13, 2019): 951–60. http://dx.doi.org/10.1177/0954409718822870.

Повний текст джерела

Анотація:

The simultaneous presence of bending moments and torques produced by the lateral and vertical contact forces between the wheel and the rail generates a complex strain state on the rail surface, which makes it difficult to identify the strain signals produced purely from the lateral contact force. In this study, a new strain gauge configuration is proposed to decouple strain signals of the wheel–rail lateral contact force from wayside measurements by analyzing the bending strains on the rail web using a full Wheatstone bridge. For this purpose, a finite element modeling of the wheel–rail contact is performed to analyze the bending strains on the rail web and to optimize two instrumented sections for eight electric resistance strain gauges. Laboratory testing is also used to examine the installation scheme of the strain gauges at the two optimal instrumented sections. A good agreement is observed between the experimental data and the simulation results. Strain signals are evenly distributed for about 10 cm in the middle region between the two optimal instrumented sections and only account for the lateral contact force.

Стилі APA, Harvard, Vancouver, ISO та ін.

8

Leski, Andrzej, Wojciech Wronicz, Piotr Kowalczyk, Michał Szmidt, Robert Klewicki, Karol Włodarczyk, and Grzegorz Uliński. "Modular Test Stand for Fatigue Testing of Aeronautical Structures – Verification of Assumptions." Fatigue of Aircraft Structures 2020, no. 12 (December 1, 2020): 78–91. http://dx.doi.org/10.2478/fas-2020-0008.

Повний текст джерела

Анотація:

Abstract The Modular Test Stand was developed and manufactured to decrease the cost of fatigue testing and reduce the time of its completion as well as to enable testing specimens under more complex load conditions. The stand consists of three connected sections, similar to a wing box, all being loaded in the same way. Thanks to that, several specimens can be tested simultaneously. This configuration requires that stress and strain distribution should be reasonably uniform, as assumed in the design stage. The structure can be loaded with bending or torsion. A whole section, selected structural node or a specimen mounted in the structure as well as a repair or a sensor can be a test object. Two stands, one for bending and one for torsion were prepared. This paper presents the verification of the assumed strain and stress distributions on the skin panels. The measurements were performed with the use of Digital Image Correlation (DIC) as well as strain gauges. DIC measurements were performed on one skin panel of the central section. Five strain gauge rosettes were installed on both panels of the one section. In addition, one rosette was applied to one skin panel in each of two other sections. Measurements were performed on the stand for torsion as well as on the stand for bending. The results of DIC analysis and strain gauge measurement during torsion show uniform shearing strain distributions on the panels. During bending, on the tensioned side, the strains obtained indicate quite uniform strain distributions. On the compressed side, local buckling of the skin panels results in high strain gradients. Strain levels obtained with the use of a DIC analysis and strain gauge measurements were similar. Moreover, horizontal displacements of markers in the spar axis during bending was determined based on a series of photographic. The deflection line obtained in this way has a shape similar to arc, which is characteristic of the constant bending moment. The stand was tested with torsional and bending loads in order to verify the design assumptions. The results of strain distributions on the skin panels with the use of DIC and strain gauges as well as the deflection line of the spar axis indicate that the Modular Test Stand performs as assumed and can be used for tests.

Стилі APA, Harvard, Vancouver, ISO та ін.

9

Devivier, C., Daniel Thompson, Fabrice Pierron, and M. R. Wisnom. "Correlation between Full-Field Measurements and Numerical Simulation Results for Multiple Delamination Composite Specimens in Bending." Applied Mechanics and Materials 24-25 (June 2010): 109–14. http://dx.doi.org/10.4028/www.scientific.net/amm.24-25.109.

Повний текст джерела

Анотація:

This paper studies the effect of delaminations on strain maps for a simple cantilever beam. The aim is to build an experimental set-up which allows detecting very slight modifications in the strain maps. The case studied is a single delamination on the mid-plane. The measurement method is the deflectometry technique which enables direct slope measurements on a reflective specimen. The comparison with finite element models clearly indicated that the surface strains bear the information of the extent of the delamination. The second step is to use these surface strains to identify a stiffness reduction map for real impact damages.

Стилі APA, Harvard, Vancouver, ISO та ін.

10

Xu, Y., and R. N. Miles. "FULL-FIELD RANDOM BENDING STRAIN MEASUREMENT OF A PLATE FROM VIBRATION MEASUREMENT." Journal of Sound and Vibration 191, no. 5 (April 1996): 847–58. http://dx.doi.org/10.1006/jsvi.1996.0159.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

11

Gürbüz, Riza. "Experimental Measurement of Maximum Bending Stress on Rectangular Aluminum Beam." Solid State Phenomena 220-221 (January 2015): 413–18. http://dx.doi.org/10.4028/www.scientific.net/ssp.220-221.413.

Повний текст джерела

Анотація:

In this study, maximum bending stresses occurring on the rectangular aluminum beam under various small loads were measured with strain gauge, data acquisition cards and computer. Special software was developed to measure maximum strain and stress on the aluminum beam. Stress values occurring on the aluminum beam under various small loads were measured with strain gauge and those strain values were transmitted to computer directly with data cards. Using the strain, the load and other constant values of the material (Young’s modulus, dimensions, cross section area, load, Poisson’s rate, etc.), the stress values occurring on the beam are calculated and the stress-strain graph is drawn on the screen automatically. In this experimental study, the theoretical knowledge given in the books and experiment results obtained under laboratory conditions were compared with each other. The obtained results were almost 99% similar. Similar studies have characteristics that can be used to measure maximum bending and torsion stresses for real applications in the industry and mobile loading machines.

Стилі APA, Harvard, Vancouver, ISO та ін.

12

Vuong, Quang Dao, Ji-woong Lee, Won-Ju Lee, Hyejin Choi, Kanghyun Seo, Youngmin Kim, Jin Hui Jeong, Myeong-ho Song, and Jae-ung Lee. "Establishing the True Dynamic Bending Moment of Propeller Shaft Using a Single Bridge of Strain Gauge." Applied Sciences 12, no. 18 (September 15, 2022): 9235. http://dx.doi.org/10.3390/app12189235.

Повний текст джерела

Анотація:

The measurement of shaft bending (whirling) moment can be performed via a telemetry system including strain gauges which can obtain the bending stress. By using a single bridge of strain gauge, it was possible to obtain only the nominal bending moment. However, in case of the propeller shaft vibration measurement, the true dynamic bending moment is needed to evaluate the effect of propeller forces on the stability of the bearings. To deal with this, typically two bridges of strain gauge at 90 degrees are needed. This research presents a novel reliability assessment method in establishing the true dynamic bending moment using only one bridge of strain gauge. This is achieved by using the actual bending stress measured by strain gauge combined with its own phase lag stress at an angle of 90 degrees. To validate this technique, the experiments were performed under the rapid turning transient states during a sea trial of a 50,000 DWT oil/chemical tanker. As a result, great fluctuations in propeller force were detected, resulting in a non-uniform oil film in the bearings. The displacement sensor was also installed and confirmed the established true dynamic bending moment.

Стилі APA, Harvard, Vancouver, ISO та ін.

13

Weisbrich, Martin, and Klaus Holschemacher. "Comparison between different fiber coatings and adhesives on steel surfaces for distributed optical strain measurements based on Rayleigh backscattering." Journal of Sensors and Sensor Systems 7, no. 2 (November 21, 2018): 601–8. http://dx.doi.org/10.5194/jsss-7-601-2018.

Повний текст джерела

Анотація:

Abstract. Optical fiber measurement systems have recently gained popularity following a multitude of intensive investigations. A new technique has been developed for these measurement systems that uses Rayleigh backscatter to determine the distributed strain measurement over the total length of a fiber. These measurement systems have great potential in civil engineering and structural health monitoring. This paper addresses some preliminary comparisons between three different fiber coatings and six different adhesives on steel structures. The results are based on a bending test with specimens made of precision flat steel; optical fiber strain measurements were compared with photogrammetric strain measurements. Analysis of the test data showed a strong correlation between the optical measurement system's results and the theoretical results up to the yielding point of the steel. Furthermore, the results indicate that fibers with the Ormocer® and polyimide coatings have almost the same strain values as the reference measurement method. The main results of this investigation are a guideline describing how to attach optical fibers to steel surfaces for distributed fiber optical strain measurements and recommendations for coatings to obtain realistic strain values. Additionally, the advantages of distributed strain measurements were revealed, which illustrates the potential of Rayleigh backscattering applications.

Стилі APA, Harvard, Vancouver, ISO та ін.

14

Kim, Min Seok, Do Kyung Kim, Jihoon Kim, Seul-Lee Lee, Sungwook Choi, Jinsil Han, and Yong Wook Lee. "Strain-Insensitive Simultaneous Measurement of Bending and Temperature Using Long-Period Fiber Grating Inscribed on Double-Clad Fiber with CO2 Laser." Journal of Nanoscience and Nanotechnology 21, no. 3 (March 1, 2021): 1883–89. http://dx.doi.org/10.1166/jnn.2021.18908.

Повний текст джерела

Анотація:

Here we report an optical fiber sensor capable of performing strain-insensitive simultaneous measurement of bending and temperature using a long-period fiber grating (LPFG) inscribed on doubleclad fiber (DCF) with a CO2 laser at ˜10.6 μm. The LPFG inscribed on DCF, referred to as a DC-LPFG, was fabricated by scanning CO2 laser pulses on an unjacketed DCF with a specific period. Due to co-directional mode coupling, the fabricated DC-LPFG has discrete attenuation bands widely distributed over hundreds of nanometers. Among these wavelength-dependent loss dips, adjacent two dips with different resonance wavelengths were selected as sensor indicators for the measurement of bending and temperature. For these two indicator dips designated as dips A and B, their bending and temperature responses were investigated in a curvature range of 4.90 to 21.91 m−1 and a temperature range of 30 to 110 °C. With increasing bending applied to the DC-LPFG at room temperature, dips A and B showed different blue shifts. The bending sensitivities of dips A and B were measured to be approximately −0.77 and 0.51 nm/m−1, respectively. Unlike the bending response, they showed red shifts of different amounts with increasing ambient temperature, while the sensor head (i.e., the DC-LPFG) remained straight without any applied bending. The temperature sensitivities of dips A and B were measured to be ˜0.094 and ˜0.078 nm/°C, respectively. Owing to their linear and independent responses to bending and temperature, bending and temperature changes applied to the DC-LPFG could be simultaneously estimated from the measured wavelength shifts of the two indicator dips using their pre-determined bending and temperature sensitivities. Moreover, in a strain range of 0 to 2200 με (step: 200 με), strain-induced spectral variations of dips A and B were also measured, and the strain sensitivities of dips A and B were evaluated as approximately −0.028 and −0.013 pm/με, respectively. These strain-induced wavelength shifts were so small that they had little effect on the measurement results of bending and temperature. Thus, it is concluded that the fabricated DC-LPFG can be employed as a cost-effective sensor head for strain-insensitive separate measurement of bending and temperature.

Стилі APA, Harvard, Vancouver, ISO та ін.

15

He, X., J. Ma, and T. Welo. "Strain distribution at the transition from bent to unbent regions in tube rotary draw bending: an in-situ, real-time measurement study." IOP Conference Series: Materials Science and Engineering 1270, no. 1 (December 1, 2022): 012059. http://dx.doi.org/10.1088/1757-899x/1270/1/012059.

Повний текст джерела

Анотація:

In tube bending processes, accurate control of springback is of crucial importance as this affects the dimensional accuracy of the final product and overall equipment efficiency. The distribution of stress and strain during bending is one of the most fundamental issues determining the springback magnitude of the product. In conventional analyses of rotary draw bending, the deformation behaviour along the bending direction is normally assumed to be uniform for constant-radius bends, following the contour of the die configuration. In practice, however, the stress-strain distribution is non-uniform, particularly at the transition between the bent and unbent regions of the formed component. The distribution makes a significant contribution to springback and its variations, especially for low bend-angle components. This research focuses on exploring the strain distribution at the end transition of the bend of aluminium tubes in rotary draw bending. An experimental test setup for strain measurements with a strain gauge glued to the unbent area has been designed and conducted to measure the strain distribution during bending. The characteristics of non-uniform strain distribution during tube bending, including the evolving transition behaviour at the transition between bent and unbent areas, are studied. The results enhance the understanding of deformation characteristics of bent tubes, and contribute to improved physically-based models and springback control routines in industrial practice.

Стилі APA, Harvard, Vancouver, ISO та ін.

16

Choi, Sang-Jin, Seong-Yong Jeong, Changhyun Lee, Kwon Gyu Park, and Jae-Kyung Pan. "Twisted Dual-Cycle Fiber Optic Bending Loss Characteristics for Strain Measurement." Sensors 18, no. 11 (November 16, 2018): 4009. http://dx.doi.org/10.3390/s18114009.

Повний текст джерела

Анотація:

The intensity-based fiber optic sensor (FOS) head using twisted dual-cycle bending loss is proposed and experimentally demonstrate. The bending loss characteristics depend on the steel wire radius, number, and distance. To determine the effects of these parameters, two samples in each of seven configuration cases of the proposed FOS head were bonded to fiber reinforced plastics coupons, and tensile and flexural strain tests were repeated five times for each coupon. The bending loss of the manufactured FOS heads was measured and converted to the tensile and flexural strain as a function of configuration cases. The measurement range, sensitivity, and average measurement errors of the tensile load and flexural strain were 4.5 kN and 1,760 με, 0.70 to 3.99 dB/kN and 0.930 to 6.554 dB/mm, and 57.7 N, and 42.6 με, respectively. The sensing range of FOS head were 82 to 138 mm according to configuration cases. These results indicate that it is possible to measure load, tensile strain, and flexural strain using the proposed FOS head, and demonstrate that the sensitivities, the operating ranges, and the sensing range can be adjusted depending on the deformation characteristics of the measurement target.

Стилі APA, Harvard, Vancouver, ISO та ін.

17

KARCZUB, D. G., and M. P. NORTON. "FINITE DIFFERENCING METHODS FOR THE MEASUREMENT OF DYNAMIC BENDING STRAIN." Journal of Sound and Vibration 226, no. 4 (September 1999): 675–700. http://dx.doi.org/10.1006/jsvi.1999.2317.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

18

Song, Xu, Solène Chardonnet, Giancarlo Savini, Shu Yan Zhang, Willem J. J. Vorster, and Alexander M. Korsunsky. "Experimental/Modelling Study of Residual Stress in Al/SiC_p Bent Bars by Synchrotron XRD and Slitting Eigenstrain Methods." Materials Science Forum 571-572 (March 2008): 277–82. http://dx.doi.org/10.4028/www.scientific.net/msf.571-572.277.

Повний текст джерела

Анотація:

The aim of the study presented here was to evaluate the residual stresses present in a bar of aluminium alloy 2124-T1 matrix composite (MMC) reinforced with 25vol% particulate silicon carbide (SiCp) using X-ray diffraction and 3D profilometry (curvature measurement using Mitutoyo/Renishaw coordinate measurement machine) and comparing these results with numerical models of residual strain and stress profiles obtained by a simple inelastic bending model and Finite Element Analysis (FEA). The residual strain distribution was introduced into the test piece by plastic deformation in the 4-point bending configuration. At the first stage of this study the elasticplastic behaviour of the MMC was characterized under static and cyclic loading to obtain the material parameters, hardening proprieties and cyclic hysteresis loops. Subsequently, synchrotron Xray diffraction and CMM curvature measurements were performed to deduce the residual stress profile in the central section of the bar. The experimental data obtained from these measurements were used in the inelastic bending and FEA simulations. The specimens were then subjected to incremental slitting using EDM (electric discharge machining) with continuous back and front face strain gauge monitoring. The X-ray diffraction and incremental slitting results were then analysed using direct and inverse eigenstrain methods. Residual stresses plots obtained by different methods show good agreement with each other.

Стилі APA, Harvard, Vancouver, ISO та ін.

19

Jankowski, Ludomir J., and Tomasz Nowak. "Experimental Assessment of the Glued Laminated Timber Beams in 4-Point Bending Tests and Photoelastic Coating Technique." Solid State Phenomena 240 (August 2015): 155–60. http://dx.doi.org/10.4028/www.scientific.net/ssp.240.155.

Повний текст джерела

Анотація:

The paper presents the results of investigation on seven glued laminated timber (GL24h class) bending beams. Bending strength and modulus of elasticity were determined. The beams were tested for four-point bending by loading them at a constant speed deflection. The strain gauge method and photoelastic coating technique were applied for strain distributions determination in selected cross-sections of the beams. Good agreement of the measurement results was obtained with both techniques. Application of the photoelastic coating technique enabled more detailed analysis of the beams failure mode, including timber defects influence on the strain distributions.

Стилі APA, Harvard, Vancouver, ISO та ін.

20

Valentini, Emilio, Alessio Benincasa, and Ciro Santus. "Bending Test Rig for Validating the Hole Drilling Method Residual Stress Measurement." Materials Science Forum 768-769 (September 2013): 150–57. http://dx.doi.org/10.4028/www.scientific.net/msf.768-769.150.

Повний текст джерела

Анотація:

This paper shows a large validation activity of the strain gage Hole Drilling Method. The residual stress measurements can not be validated easily, unless with Round Robin activity and/or comparison with other residual stress measurements such as X-ray diffraction. An accurate validation procedure is reported in the present paper, using abending test rig. The bending stress experimentally simulated a residual stress (known with uncertainty lower than 1%) that was considered as the reference stress distribution. The results showed very accurate measurement in terms of relaxed strain distributions, that were compared with the prediction obtained with the Influence Function technique. The differences were in the order of 0.5 microepsilon as standard deviation on a large number of tests. The bending stress prediction was consequently very accurate and the stress differences were as small as 1 MPa showing the accuracy potentiality of the method.

Стилі APA, Harvard, Vancouver, ISO та ін.

21

Yan, Hanfei, and I. C. Noyan. "Measurement of stress/strain in single-crystal samples using diffraction." Journal of Applied Crystallography 39, no. 3 (May 10, 2006): 320–25. http://dx.doi.org/10.1107/s0021889806006662.

Повний текст джерела

Анотація:

Diffraction profiles from an Si-single-crystal strip deformed in cantilever bending are presented as a function of tip displacement and incident-beam energy. Data obtained with slit-based diffracted-beam optics contain a secondary peak in addition to the primary 004 reflection for all energies when the bending strain is finite. This secondary peak can be identified as a `mirage' peak, predicted by dynamical diffraction theory to occur in weakly deformed single-crystal samples. The integrated intensity of this mirage peak increases with increasing energy and tip displacement and exceeds the primary peak intensity at higher values. The mirage peak disappears when a monochromator is used in the diffracted-beam path. Data that show the effect of these mirage peaks on X-ray diffraction strain analysis are presented, and it is shown that a diffracted-beam monochromator may be used to eliminate these errors.

Стилі APA, Harvard, Vancouver, ISO та ін.

22

Feng, Qingshan, Rui Li, and Hong Zhang. "Modeling and Calculation of Dent Based on Pipeline Bending Strain." Journal of Sensors 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/8126214.

Повний текст джерела

Анотація:

The bending strain of long-distance oil and gas pipelines can be calculated by the in-line inspection tool which used inertial measurement unit (IMU). The bending strain is used to evaluate the strain and displacement of the pipeline. During the bending strain inspection, the dent existing in the pipeline can affect the bending strain data as well. This paper presents a novel method to model and calculate the pipeline dent based on the bending strain. The technique takes inertial mapping data from in-line inspection and calculates depth of dent in the pipeline using Bayesian statistical theory and neural network. To verify accuracy of the proposed method, an in-line inspection tool is used to inspect pipeline to gather data. The calculation of dent shows the method is accurate for the dent, and the mean relative error is 2.44%. The new method provides not only strain of the pipeline dent but also the depth of dent. It is more benefit for integrity management of pipeline for the safety of the pipeline.

Стилі APA, Harvard, Vancouver, ISO та ін.

23

Zhang, En Wei, Yun Bo Yang, Wei Song, Xiao Wei Wei, Zhi Bin Qiu, Jiang Jun Ruan, and Dao Chun Huang. "Study on Bending and Twisting Mechanical Properties of High Voltage Porcelain Post Insulator." Applied Mechanics and Materials 521 (February 2014): 334–38. http://dx.doi.org/10.4028/www.scientific.net/amm.521.334.

Повний текст джерела

Анотація:

To study the mechanical properties of porcelain post insulators, the finite element model was established by ANSYS to calculate stress and strain distribution under bending or torsion moments. Mechanical tests based on resistance strain measurement technology were carried out on the actual porcelain post insulators to measure their strain distribution. The results show that sheds will cause strain concentration at the roots of porcelain column whether the post insulator is bearing bending or torsion load. The stress and strain of shed roots gradually increase from top to bottom along the post insulator when bearing bending moment, while they are relatively uniform under torsion moment. It should be taken full account of the stress concentration caused by sheds during the selection or maintenance of porcelain post insulators.

Стилі APA, Harvard, Vancouver, ISO та ін.

24

HOJO, Akihiro, Akiyosi CHATANI, and Hiroshi TACHIYA. "K-0744 Measurement of Stress-Strain Curve By Impact Bending Test." Proceedings of the JSME annual meeting I.01.1 (2001): 377–78. http://dx.doi.org/10.1299/jsmemecjo.i.01.1.0_377.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

25

Tetzel, H., M. Grden, and F. Vollertsen. "Stress analysis based on strain measurement in sheet metal laser bending." Production Engineering 7, no. 6 (August 7, 2013): 647–55. http://dx.doi.org/10.1007/s11740-013-0488-9.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

26

Zhu, Si Rong, Liu Lin Kong, Zhuo Qiu Li, and Yong Lv. "Strain Measurement in Two-Dimension Stresses Based on Polymer-Matrix Carbon Fiber Smart Stripes." Advanced Materials Research 211-212 (February 2011): 480–84. http://dx.doi.org/10.4028/www.scientific.net/amr.211-212.480.

Повний текст джерела

Анотація:

The paper aims to sense strains of structures in two-dimension stress states and to perform a large-region strain monitoring. Polymer-matrix Carbon Fiber Smart Stripes (CFSS) distributed in two ways are stuck on a bending plate to detect strains using the piezoresistivity of CFSS. Monotonous tests are conducted to calibrate the surface piezoresistivity of the CFSS and then cyclic tests are conducted to measure the strains of the structure using the constitutive relation of CFSS. Results show the experimental values by CFSS fairly good with those by gage factors.

Стилі APA, Harvard, Vancouver, ISO та ін.

27

Djordjevich, A. "Structural deflection measurement." Journal of Strain Analysis for Engineering Design 38, no. 1 (January 1, 2003): 37–44. http://dx.doi.org/10.1243/030932403762671872.

Повний текст джерела

Анотація:

The concept of measuring deflection curvature of structures under bending loading with a device called a ‘curvature gauge’ is described. The application domain is specified in which this concept offers advantages over the alternative of measuring strain in terms of the measurement sensitivity, flexibility to choose the location for the sensor placement and immunity to the effects of microstructural interfacing between dissimilar materials that the sensor presence introduces. Details of the curvature gauge sensor are also given.

Стилі APA, Harvard, Vancouver, ISO та ін.

28

Ichkitidze, Levan P., Alexander Yu Gerasimenko, Dmitry V. Telyshev, Eugeny P. Kitsyuk, Vladimir A. Petukhov, and Sergei V. Selishchev. "Strain Sensor Based on Biological Nanomaterial." Engineering Proceedings 6, no. 1 (May 17, 2021): 23. http://dx.doi.org/10.3390/i3s2021dresden-10115.

Повний текст джерела

Анотація:

We investigated a prototype of a strain sensor based on the layers of a bionanomaterial containing bovine serum albumin (BSA matrix) and multi-walled carbon nanotubes (MWCNT filler). The aqueous dispersion of 25 wt.% BSA/0.3 wt.% MWCNT was applied by screen printing onto flexible polyethylene terephthalate substrates. After drying the layers by laser irradiation (~970 nm), various parameters of the layers were controlled, i.e., resistance R, bending angle θ, number of cycles n, and measurement time. One measurement cycle corresponded to a change within the range θ = ±150°. The layers of the BSA/MWCNT bionanomaterial had dimensions of (15 ÷ 20) mm × (8 ÷ 10) mm × (0.5 ÷ 1. 5) µm. The dependences of resistance R on the bending angle θ were similar for all layers at θ = ±30, and the R(θ) curves represented approximate linear dependences (with an error of ≤ 10%); beyond this range, the dependences became nonlinear. The following quantitative values were obtained for the investigated strain sensor: specific conductivity ~1 ÷ 10 S/m, linear strain sensitivity ~160, and bending sensitivity 1.0 ÷ 1.5%/°. These results are high. The examined layers of the bionanomaterial BSA/MWCNT as a strain sensor are of particular interest for medical practice. In particular, strain sensors can be implemented by applying a water dispersion of nanomaterials to human skin using a 3D printer for monitoring movements (arms and blinking) and the detection of signs of pathology (dysphagia, respiratory diseases, angina, etc.).

Стилі APA, Harvard, Vancouver, ISO та ін.

29

Lee, Song-Bi, Young-Jun Jung, Hun-Kook Choi, Ik-Bu Sohn, and Joo-Hyeon Lee. "Hybrid LPG-FBG Based High-Resolution Micro Bending Strain Sensor." Sensors 21, no. 1 (December 22, 2020): 22. http://dx.doi.org/10.3390/s21010022.

Повний текст джерела

Анотація:

Sensitivity and reliability are essential factors for the practical implementation of a wearable sensor. This study explores the possibility of using a hybrid high-resolution Bragg grating sensor for achieving a fast response to dynamic, continuous motion and Bragg signal pattern monitoring measurement. The wavelength shift pattern for real-time monitoring in picometer units was derived by using femtosecond laser Bragg grating processing on an optical wave path with long-period grating. The possibility of measuring the demodulation system’s Bragg signal pattern on the reflection spectrum of the femtosecond laser precision Bragg process and the long-period grating was confirmed. By demonstrating a practical method of wearing the sensor, the application of wearables was also explored. It is possible to present the applicability of sophisticated micro transformation measurement applications in picometer units.

Стилі APA, Harvard, Vancouver, ISO та ін.

30

Schöberl, Erich, MN Mavrogordato, I. Sinclair, and SM Spearing. "Fibre direction strain measurement in a composite ply under pure bending using Digital Volume Correlation and Micro-focus Computed Tomography." Journal of Composite Materials 54, no. 14 (April 22, 2020): 1889–912. http://dx.doi.org/10.1177/0021998320918648.

Повний текст джерела

Анотація:

This paper presents an experimental demonstration and validation of high-resolution three-dimensional experimental strain measurement using Digital Volume Correlation (DVC) on Carbon Fibre-Reinforced Polymers, via through-thickness strain analysis under a state of pure bending. To permit the application of DVC to displacements and/or strain measurements parallel to the fibre direction in well-aligned unidirectional materials at high volume fractions, a methodology was developed for the insertion of sparse populations of 400 nm BaTiO3 particles within the matrix to act as displacement trackers (i.e. fiducial markers). For this novel material system, measurement sensitivity and noise are considered, along with the spatial filtering intrinsic to established DVC data processing. In conjunction with Micro-focus Computed Tomography, the technique was applied to a simple standard specimen subjected to a four-point flexural test, which resulted in a linear strain distribution through the beam thickness. The high-resolution, fibre-level strain distributions (imaged at a voxel resolution of ∼0.64 µm) were compared against the classical beam theory (Euler–Bernoulli) in incrementally decreasing averaging schemes and different sub-set sizes. Different sampling and averaging strategies are reported, showing that DVC outputs can be obtained that are in very good agreement with the analytical solution. A practical lower limit for the spatial resolution of strain is discerned for the present materials and methods. This study demonstrates the effectiveness of DVC in measuring local strains parallel to the fibre direction, with corresponding potential for calibration and validation of micromechanical models predicting various fibre-dominated damage mechanisms.

Стилі APA, Harvard, Vancouver, ISO та ін.

31

Jiang, Qing Hai, Yu Sun, and Xiao Yong Xu. "Study on Eliminating the Effect of Bending Moment in Torque Measurement." Applied Mechanics and Materials 217-219 (November 2012): 2293–98. http://dx.doi.org/10.4028/www.scientific.net/amm.217-219.2293.

Повний текст джерела

Анотація:

The function characteristics of bending moment and torque were analyzed based on the principle of torque measurement and the adverse effect of bending moment to torque measurement was proved theoretically. By distributing the positions of resistance strain gauge on the transmission shaft and the relative positions in the bridge, an effective method of eliminating the adverse effect of bending moment was proposed base on the principle of superposition and counterbalance in the bridge, and the potential errors were analyzed and corrected. Then the proposed method was applied in measuring the torque of a motor shaft. The result shows that the effect of bending moment has been eliminated, and this method is feasible and effective.

Стилі APA, Harvard, Vancouver, ISO та ін.

32

Cofaru, Nicolae, Lucian Roman, Adrian Pascu, and Valentin Oleksik. "Experimental Study Regarding of Bending Behaviour of Stabilizator Link." ACTA Universitatis Cibiniensis 68, no. 1 (December 1, 2016): 12–15. http://dx.doi.org/10.1515/aucts-2016-0003.

Повний текст джерела

Анотація:

Abstract This paper presents an experimental study of the behavior of anti-roll power link subjected to bending, power link coming from an Opel Astra G. The power link is made of PA66 GF30 polyamide. For this study, there were used a universal testing machine (Instron 5587) and a real-time strain measurement optical system (Aramis). The results showed are those obtained in the case of a compression force of 1,000 [N] namely: major Strain ε1, minor strain ε2, equivalent von Mises strain, displacement on X axis, displacement on Y axis (compression force direction), displacement on Z axis.

Стилі APA, Harvard, Vancouver, ISO та ін.

33

Taniguchi, Kazuhiro, Etsuko Kobayashi, Sanghyun Joung, Minoru Ono, Noboru Motomura, Shunei Kyo, Shinichi Takamoto, and Ichiro Sakuma. "A Force Measurement Device Using Optical Fiber for Surgical Tools - Basic Concept and Implementation -." Journal of Robotics and Mechatronics 23, no. 1 (February 20, 2011): 94–104. http://dx.doi.org/10.20965/jrm.2011.p0094.

Повний текст джерела

Анотація:

The system proposed here measures compressive and tensile stress working longitudinally in an endoscopic surgical-assistant robot tool for the palpation of lung cancer. The force sensor is a safe, sanitary Fiber Bragg Grating (FBG) strain sensor. Such sensors are suitable for medical applications but have the disadvantage of force measurement being adversely affected by temperature. An FBG sensor on a workpiece is strained simultaneously with the workpiece to measure force based on the strain degree. A workpiece with a high Young’s modulus decrease strain, compromising sensor measurement resolution. Our proposal, discussed and evaluated in the sections that follow, solves these problems of temperature compensation and measurement resolution. The trial device we fabricated amplifies strain to enhance measurement resolution. We measured FBG sensor performance by applying compressive and tensile stress longitudinally on the trial device and determined, based on measurement results, that strain was amplified. We also confirmed that FBG sensormeasurement corresponded linearly to the compressive and tensile stress of 0-3 N. The trial device we fabricated filtered bending and torsional stress – excluding tensile and compressive stress – applied to the workpiece and confirmed device effectiveness in suppressing bending and torsional stress. Our trial device for temperature compensation solves the problems of the FBG sensor within a small, lightweight package.

Стилі APA, Harvard, Vancouver, ISO та ін.

34

Jebáček, Ivo, and Marek Horak. "POSSIBILITIES AND METHODS OF IN-FLIGHT LOADING MEASUREMENT." Aviation 16, no. 2 (June 29, 2012): 47–50. http://dx.doi.org/10.3846/16487788.2012.701860.

Повний текст джерела

Анотація:

This article provides information about in-flight measurement of a small sport aircraft. First strain gauges were installed in the wing structure and then calibration procedures were done. After the calculation of strain gauge coefficients, equations for calculating bending moments and other variables were established. A data acquisition system was installed in the aircraft to measure responses from strain gauges and other variables such as speed, altitude, load factor, and temperature. Many flights were performed with the aircraft equipped this way, and after that the recorded data were analysed and those results were compared with the calculations and static strength tests performed before.

Стилі APA, Harvard, Vancouver, ISO та ін.

35

Markvart A. A., Liokumovich L. B., and Ushakov N. A. "Fiber Optic SMS Sensor for Simultaneous Measurement of Strain and Curvature." Technical Physics Letters 48, no. 15 (2022): 30. http://dx.doi.org/10.21883/tpl.2022.15.53817.18969.

Повний текст джерела

Анотація:

The article presents a fiber-optic sensor based on a singlemode-multimode-singlemode (SMS) structure for simultaneous measurement of strain and curvature. It is shown that the simultaneous demodulation of strain and curvature can be realized using the Fourier analysis of the recorded interference oscillations. Keywords: optical fiber sensors, intermode interference, single mode-multimode-single mode, stretching, bending.

Стилі APA, Harvard, Vancouver, ISO та ін.

36

Neubauer, Moritz, Martin Dannemann, Niklas Herzer, Benjamin Schwarz, and Niels Modler. "Analysis of a Film Forming Process through Coupled Image Correlation and Infrared Thermography." Polymers 14, no. 6 (March 18, 2022): 1231. http://dx.doi.org/10.3390/polym14061231.

Повний текст джерела

Анотація:

The aim of the present investigation was to determine the dependence of the material and process parameters of the bending process of thermoplastic films. In this context, parameter combinations leading to high resulting forming ratios were identified. To measure the relevant parameters within the hot bending process, a coupled evaluation of infrared thermography (IRT) and deformation measurement using digital image correlation (DIC) was performed. The coupled measurement enables the identification of the actual mechanically stressed bending area of the film as a result of the bending process. This allows for the specification of the local forming temperatures required for the desired forming ratios. Furthermore, the mechanical and thermal strain along the defined measuring sections and their deviation in individual tests as well as the effect of thermal strain on process control on a larger scale were determined. Based on the results, a process window was defined for the film materials investigated, which will serve as a starting point for future efforts to develop a continuous manufacturing process.

Стилі APA, Harvard, Vancouver, ISO та ін.

37

Hojo, Akihiro, Akiyoshi Tyatani, and Hiroshi Tachiya. "On the Measurement of Dynamic Stress-Strain Curve by Impact Bending Test." Proceedings of the 1992 Annual Meeting of JSME/MMD 2000 (2000): 585–86. http://dx.doi.org/10.1299/jsmezairiki.2000.0_585.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

38

SATO, Masashi, Shin-ichi TAKEDA, and Toshio OGASAWARA. "Strain measurement in CFRP laminates under bending load using tilted FBG sensors." Proceedings of Mechanical Engineering Congress, Japan 2018 (2018): J0460403. http://dx.doi.org/10.1299/jsmemecj.2018.j0460403.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

39

Santana, Luis, Diego Rivera, and Eric Forcael. "Force Measurement with a Strain Gauge Subjected to Pure Bending in the Fluid–Wall Interaction of Open Water Channels." Applied Sciences 12, no. 3 (February 8, 2022): 1744. http://dx.doi.org/10.3390/app12031744.

Повний текст джерела

Анотація:

An experimental method to measure forces of small magnitude with a strain gauge as a force sensor in the fluid–wall interaction of open water channels is presented. Six uniaxial strain gauges were employed for this purpose, which were embedded across the entire sensing area and subjected to pure bending, employing two-point bending tests. Sixteen two-point bending tests were performed to determine the existence of a direct relationship between the load and the instrument signal. Furthermore, a regression analysis was used to estimate the parameters of the model. A data acquisition system was developed to register the behavior of the strain gauge relative to the lateral displacement induced by the loading nose of the universal testing machine. The results showed a significant linear relationship between the load and the instrumental signal, provided that the strain gauge was embedded between 30% and 45% of the central axis in the sensing area of the sensor (R2 > 0.99). Thus, the proposed sensor can be employed to measure forces of small magnitude. Additionally, the linear relationship between the load and the instrumental signal can be used as a calibration equation, provided that the strain gauge is embedded close to the central axis of the sensing area.

Стилі APA, Harvard, Vancouver, ISO та ін.

40

Pan, Jian Ou, Yu Jing Jia, and Guang Zhen Cheng. "The Research of Pure Bending Flanged Beam’s Stress Distribution in Civil Engineering." Advanced Materials Research 568 (September 2012): 168–71. http://dx.doi.org/10.4028/www.scientific.net/amr.568.168.

Повний текст джерела

Анотація:

Experimental method is an important means to research the mechanical properties of materials in civil engineering. In this paper, first, analyzing the section of pure bending beam’s normal-stress distribution, drafting the measure scheme of flanged beam’s pure bending normal-stress, arranging measuring point in different place about the section of pure bending, adopting multi-function composite test-bed, static strain gauge and other testing instrument, by step loading, to finish the measure of each measuring points’ stress and strain, also, analysis and treatment for test data. According to the result of analysis and treatment, pointing out that measured stress and strain of pure bending beam is proportional to loading. The measured normal-stress distribution of the pure bend beam is uniform with theoretical analysis, which is satisfy the engineering demand. Knowing and mastering multipoint measurement technology and method is an effective means for the scientific research.

Стилі APA, Harvard, Vancouver, ISO та ін.

41

Hren, Philip D. "Strain measurement by means of bend contour microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 210–11. http://dx.doi.org/10.1017/s0424820100153026.

Повний текст джерела

Анотація:

The pattern of bend contours which appear in the TEM image of a bent or curled sample indicates the shape into which the specimen is bent. Several authors have characterized the shape of their bent foils by this method, most recently I. Bolotov, as well as G. Möllenstedt and O. Rang in the early 1950’s. However, the samples they considered were viewed at orientations away from a zone axis, or at zone axes of low symmetry, so that dynamical interactions between the bend contours did not occur. Their calculations were thus based on purely geometric arguments. In this paper bend contours are used to measure deflections of a single-crystal silicon membrane at the (111) zone axis, where there are strong dynamical effects. Features in the bend contour pattern are identified and associated with a particular angle of bending of the membrane by reference to large-angle convergent-beam electron diffraction (LACBED) patterns.

Стилі APA, Harvard, Vancouver, ISO та ін.

42

Jenkins, R. Brian, Peter Joyce, Adam Kong, and Charles Nelson. "Discerning Localized Thermal Heating from Mechanical Strain Using an Embedded Distributed Optical Fiber Sensor Network." Sensors 20, no. 9 (May 1, 2020): 2583. http://dx.doi.org/10.3390/s20092583.

Повний текст джерела

Анотація:

Prior research has demonstrated that distributed optical fiber sensors (DOFS) based on Rayleigh scattering can be embedded in carbon fiber/epoxy composite structures to rapidly detect temperature changes approaching 1000 °C, such as would be experienced during a high energy laser strike. However, composite structures often experience mechanical strains that are also detected during DOFS interrogation. Hence, the combined temperature and strain response in the composite can interfere with rapid detection and measurement of a localized thermal impulse. In this research, initial testing has demonstrated the simultaneous response of the DOFS to both temperature and strain. An embedded DOFS network was designed and used to isolate and measure a localized thermal response of a carbon fiber/epoxy composite to a low energy laser strike under cyclic bending strain. The sensor interrogation scheme uses a simple signal processing technique to enhance the thermal response, while mitigating the strain response due to bending. While our ultimate goal is rapid detection of directed energy on the surface of the composite, the technique could be generalized to structural health monitoring of temperature sensitive components or smart structures.

Стилі APA, Harvard, Vancouver, ISO та ін.

43

Iyama, J., O. Chih-Chun, and K. Araki. "Bending moment distribution estimation of an actual steel building structure by microstrain measurement under small earthquakes." Journal of Civil Structural Health Monitoring 11, no. 3 (April 16, 2021): 791–807. http://dx.doi.org/10.1007/s13349-021-00482-z.

Повний текст джерела

Анотація:

AbstractMost structural health monitoring systems estimate the overall behavior by measuring the acceleration response, which cannot directly measure the stress or damage state of individual structural members. An alternative approach is to use strain measurements; however, methods for analyzing and utilizing strain data for actual steel buildings have not been established. In this study, highly precise semiconductor strain gauges were applied to an actual building. The accelerations and strains measured during earthquake loading were used to calculate the ratio of the bending moment at the beam or column sections to the displacement at the top of the building, which was defined as the “local stiffness.” This physical index represents the stiffness of structural elements near the measurement location and can be easily predicted through simple static frame analysis. The measured local stiffness was comparable to the analytical local stiffness values for the beams but was larger than that for the columns. This indicates that nonstructural members may exhibit a certain degree of restoring force and that the measured local stiffness may be strongly affected by nonstructural elements that are not considered during the structural design stage. Conversely, the measured local stiffness can be used to estimate the behavior of nonstructural components. The measured dominant frequency and local stiffness of the beams and columns showed a dependency on amplitude, but opposite trends were observed for the beams and columns. This indicates that the amplitude dependency of the dominant frequency is not due to the behavior of the beams and columns but to other reasons such as nonstructural components or changes in mass.

Стилі APA, Harvard, Vancouver, ISO та ін.

44

Hisada, Shinsaku, Utanori Kodakamine, Daichi Wada, Hideaki Murayama, and Hirotaka Igawa. "Simultaneous Measurement of Strain and Temperature Distributions Using Optical Fibers with Different GeO2 and B2O3 Doping." Sensors 23, no. 3 (January 19, 2023): 1156. http://dx.doi.org/10.3390/s23031156.

Повний текст джерела

Анотація:

Compensating for the effects of temperature is a crucial issue in structural health monitoring when using optical fiber sensors. This study focused on the change in sensitivity due to differences in GeO2 and B2O3 doping and then verified the accuracy when measuring the strain and temperature distributions simultaneously. Four types of optical fiber sensors were utilized to measure the strain and temperature in four-point bending tests, and the best combination of the sensors resulted in strain and temperature errors of 28.4 μϵ and 1.52 °C, respectively. Based on the results obtained from the four-point bending tests, we discussed the error factors via an error propagation analysis. The results of the error propagation analysis agreed well with the experimental results, thus indicating the effectiveness of the analysis as a method for verifying accuracy and error factors.

Стилі APA, Harvard, Vancouver, ISO та ін.

45

Liu, Shucong, Hongjun Wang, Rui Li, and Beilei Ji. "A Novel Feature Identification Method of Pipeline In-Line Inspected Bending Strain Based on Optimized Deep Belief Network Model." Energies 15, no. 4 (February 21, 2022): 1586. http://dx.doi.org/10.3390/en15041586.

Повний текст джерела

Анотація:

Both long-distance oil and gas pipelines often pass through areas with unstable geological conditions or natural disasters. As a result, they are prone to bending, displacement, and deformation due to the action of an external environmental loading, which poses a threat to the safe operation of pipelines. The in-line inspection method that is based on the implementation of high-precision inertial measurement units (IMU) has become the main means of pipeline bending stress-strain detection technique. However, to address the problems of the inconsistent identification, low identification efficiency, and high misjudgment rate during the application of the traditional manual identification methods, a feature identification approach for the in-line inspected pipeline bending strain based on the employment of an optimized deep belief network (DBN) model is proposed in this work. In addition, our model can automatically learn features from the pipeline bending strain signals and complete classification and identification. On top of that, after the network model was trained and tested by using the actual pipeline bending strain inspection data, the extracted results showed that the model after the implementation of the training process could accurately identify and classify various pipeline features, with an identification accuracy and efficiency of 97.8% and 0.02 min/km, respectively. The high efficiency, elevated accuracy, and strong robustness of our method can effectively improve the in-line inspection procedure of pipelines during the enforcement of a bending strain load.

Стилі APA, Harvard, Vancouver, ISO та ін.

46

Choi, Yunyeong, Jisun Park, and Hyungsoon Shin. "New Simulation Method for Dependency of Device Degradation on Bending Direction and Channel Length." Materials 14, no. 20 (October 18, 2021): 6167. http://dx.doi.org/10.3390/ma14206167.

Повний текст джерела

Анотація:

The dependency of device degradation on bending direction and channel length is analyzed in terms of bandgap states in amorphous indium-gallium-zinc-oxide (a-IGZO) films. The strain distribution in an a-IGZO film under perpendicular and parallel bending of a device with various channel lengths is investigated by conducting a three-dimensional mechanical simulation. Based on the obtained strain distribution, new device simulation structures are suggested in which the active layer is defined as consisting of multiple regions. The different arrangements of a highly strained region and density of states is proportional to the strain account for the measurement tendency. The analysis performed using the proposed structures reveals the causes underlying the effects of different bending directions and channel lengths, which cannot be explained using the existing simulation methods in which the active layer is defined as a single region.

Стилі APA, Harvard, Vancouver, ISO та ін.

47

Javed, Zafar, Lybah Rafiq, Muhammad Anwaar Nazeer, Saqib Siddiqui, Muhammad Babar Ramzan, Muhammad Qamar Khan, and Muhammad Salman Naeem. "Piezoelectric nanogenerator for bio-mechanical strain measurement." Beilstein Journal of Nanotechnology 13 (February 7, 2022): 192–200. http://dx.doi.org/10.3762/bjnano.13.14.

Повний текст джерела

Анотація:

Piezoelectric materials have attracted more attention than other materials in the field of textiles. Piezoelectric materials offer advantages as transducers, sensors, and energy-harvesting devices. Commonly, ceramics and quartz are used in such applications. However, polymeric piezoelectric materials have the advantage that they can be converted into any shape and size. In smart textiles, polyvinylidene fluoride (PVDF) and other piezoelectric polymers are used in the form of fibers, filaments, and composites. In this research, PVDF nanofibers were developed and integrated onto a knitted fabric to fabricate a piezoelectric device for human body angle monitoring. Scanning electron microscopy and X-ray diffraction analyses were used to study the morphology and to confirm the beta phase in fibers. The results reveal that the nanofibers made from solutions with high concentration were smooth and defect-free, compared to the fibers obtained from solutions with low concentration, and possess high crystallinity as well. Under high dynamic strain more output voltage is generated than under low dynamic strain. The maximum current density shown by the device is 172.5 nA/cm2. The developed piezoelectric nanofiber sensor was then integrated into a knitted fabric through stitching to be used for angle measurement. With increasing bending angle, the output voltage increased. The promising results show that the textile-based piezoelectric sensor developed in this study has a great potential to be used as an angle measuring wearable device for the human body due to its high current density output and flexibility.

Стилі APA, Harvard, Vancouver, ISO та ін.

48

Sun, Guangkai, Yang Hu, Mingli Dong, Yanlin He, Mingxin Yu, and Lianqing Zhu. "Posture measurement of soft pneumatic bending actuator using optical fibre-based sensing membrane." Industrial Robot: the international journal of robotics research and application 46, no. 1 (January 21, 2019): 118–27. http://dx.doi.org/10.1108/ir-08-2018-0159.

Повний текст джерела

Анотація:

Purpose Soft robotics is a burgeoning field owing to its high adaptability and safety in human–machine interaction and unstructured environments. However, the feedback control of soft actuators with flexible sensors is still a challenge. Design/methodology/approach To address this issue, this study proposes an optical fibre-based sensing membrane for the posture measurement of soft pneumatic bending actuators. The major contribution is the development of a flexible sensing membrane with a high sensitivity and repeatability for the feedback control of soft actuators. The characteristics of sensing membrane were analysed. The relationship between wavelength shift and bending curvature was derived. The curvatures of soft actuator were measured at four bending status, and the postures were reconstructed. Findings The results indicate that the measurement error is less than 2.1% of the actual bending curvature. The sensitivity is up to 212.8 pm/m−1, and the signal fluctuation in repeated measurements is negligible. This approach has broad application prospects in soft robotics, because it makes the optical fibre achieve more strength and compatible with soft actuators, thus improving the sensing accuracy, sensitivity and reliability of fibre sensors. Originality/value Different from previous approaches, an optical fibre with FBGs is embedded into a multilayered polyimide film to form a flexible sensing membrane, and the membrane is embedded into a soft pneumatic bending actuator as the smart strain limited layer which is able to measure the posture in real time. This approach makes the optical fibre stronger and compatible with the soft pneumatic bending actuator, and the sensing accuracy, sensitivity and reliability are improved. The proposed sensing configuration is effective for the feedback control of the soft pneumatic bending actuators.

Стилі APA, Harvard, Vancouver, ISO та ін.

49

Zhang, Hui, Chengqi Zhou, Kuan Li, Peiwei Gao, Youqiang Pan, and Zhixiang Zhang. "Material and Structural Properties of Fiber-Reinforced Resin Composites as Thin Overlay for Steel Bridge Deck Pavement." Advances in Materials Science and Engineering 2019 (December 18, 2019): 1–13. http://dx.doi.org/10.1155/2019/9840502.

Повний текст джерела

Анотація:

Fatigue cracks are main damages to steel bridge deck pavement with thermosetting epoxy asphalt. By combining a high-toughness resin material with fiber woven fabrics, this study formed an ultrathin overlay of fiber-reinforced high-toughness resin to improve cracking resistance of pavement. Through theoretical measurement and bending test, this research studied change laws of bending and tensile properties of epoxy asphalt concrete after fiber reinforcement and analyzed bending strength and the maximum failure strain of beams at different temperatures. Moreover, the reinforcing effects of different fibers were discussed. It is found that bending strength, maximum failure strain, and stiffness modulus of the beams with epoxy asphalt are improved after fiber reinforcement. With the decrease of temperature, after fiber reinforcement, the mode of bending failure of the epoxy asphalt mixture (EAM) changes from brittle fracture into shear failure, accompanied with significant yield phenomenon. Furthermore, organic carbon fiber is sensitive to influences of temperature, while glass fiber is least sensitive to temperature.

Стилі APA, Harvard, Vancouver, ISO та ін.

50

SENG, KOK-YONG, and PIN-MIN LAM. "RELIABILITY OF AN ADVANCED METHOD FOR ISOMETRIC NECK MUSCLE STRENGTH MEASUREMENT." Journal of Mechanics in Medicine and Biology 02, no. 02 (June 2002): 117–29. http://dx.doi.org/10.1142/s0219519402000290.

Повний текст джерела

Анотація:

This paper is a descriptive study involving repeated within and between studies of maximal isometric strength measurements to determine the reproducibility of an advanced mechanical device in assessing maximal isometric strength of the cervical musculature. Measurements of neck muscular strength and endurance present unique challenges, due to the complexity of neck motion and absence of appropriate reference bony landmarks. Assessment of cervical musculature characteristics is further complicated by a lack of affordable and reliable measurement equipment. Previous methods commonly employed strain gauge measurement and customized helmet dynamometry, but no device, engaging a computer-controled dynamometer, has been presented so far. A new device incorporating anthropometry measurements of the local population was constructed for neck strength evaluation on the Biodex isokinetic dynamometer (Biodex, Corp., Shirley, NY). Intratester repeatability testing of the device was conducted in four principal directions: flexion, extension and left and right lateral bending. The result for intraday and day-to-day studies was good for all measured parameters. This new device can be used to measure isometric flexion, extension and lateral bending torque. By permitting the neck's 'natural' motions, it may also quantify maximal isokinetic strength and endurance ratios. Hence, the device can serve as a useful and practical tool for neck strength measurement, training and rehabilitation purposes.

Стилі APA, Harvard, Vancouver, ISO та ін.

Статті в журналах з теми "Bending strain measurement"

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями