Journal articles on the topic 'Strain gauges'
To see the other types of publications on this topic, follow the link: Strain gauges.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Strain gauges.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Gallage, Chaminda, and Chamara Jayalath. "Use of Particle Image Velocimetry (PIV) technique to measure strains in geogrids." E3S Web of Conferences 92 (2019): 12007. http://dx.doi.org/10.1051/e3sconf/20199212007.
Full textAbstract:
Geosynthetics are widely used in Geotechnical Engineering to reinforce soil/gravel in pavements, retaining wall backfills, and embankments. It is important to measure strains in geogrids in the determination of their strength parameters such as tensile strength and secant stiffness, and in evaluating their performances in geogrid-reinforced structures. Strain gauges are commonly used in measuring strains in geogrids. However, it is important to verify the strains measured by strain gauges as these strains are affected by the data logging device, gauge factors, quality of bonding between grain gauge and geogrid, and temperature. Therefore, this study was conducted to verify the performance of strain gauges attached to Geogrids and also to investigate the possibility of using PIV technique and GeoPIV-RG software to measure the local strains developed in a geogrid specimen under tensile testing in the laboratory. In the experimental program of this study, six composite geogrid specimens were tested for tensile strength (wide-width tensile tests) while measuring/calculating its tensile strain by using strain gauges attached to the specimens, Geo-PIV-RG analysis and crosshead movements of Instron apparatus. Good agreement between the strains obtained from strain gauges and geoPIV-RG analysis was observed for all the tests conducted. These results suggest that the PIV technique along with geoPIV-RG program can effectively be used to measure the local strain of geogrids in the laboratory tests. It was also able to verify that properly installed strain gauges are able to measure strain in the geogrids which are used in the field applications.
2
Cristofolini, L., B. P. McNamara, A. Freddi, and M. Viceconti. "In vitro measured strains in the loaded femur: Quantification of experimental error." Journal of Strain Analysis for Engineering Design 32, no. 3 (April 1, 1997): 193–200. http://dx.doi.org/10.1243/0309324971513337.
Full textAbstract:
The application of strain gauges to bone surfaces has been extensively employed as a method of determining, strain fields in response to implanted devices in orthopaedics. The aim of this study was to determine some of the experimental errors associated with the use of strain gauges in in vitro experimental investigations of the loaded femur. An experimental protocol was devised to obtain strain data at 20 strain gauged locations on the proximal femur. These data were interpolated using a parametric model. The parametric model was then used to estimate the errors associated with mispositioning of the gauges and deviations in their direction of application to the bone. This sensitivity analysis was also supported by a finite element analysis for the purposes of comparison and cross-validation. The results indicated that the nature of the loading normally employed in the literature can contribute to making the readings for some of the gauges (anterior and posterior) unreliable and redundant, even for small positioning errors. The greatest predicted errors for the lateral and medial gauges were due to misalignment of the gauge as opposed to mispositioning. The size of the gauge had a negligible effect on the errors predicted relative to those caused by misalignment.
3
Bednarz, Edward, Christian Dietrich, Brad Hepner, Jay Patel, and Abas Sabouni. "Determining Magnitudes of Forces at Known Locations through a Strain Gauge Force Transducer." Sensors 23, no. 16 (August 8, 2023): 7017. http://dx.doi.org/10.3390/s23167017.
Full textAbstract:
A novel strain gauge force transducer was developed to minimize the number of strain gauges needed to determine the magnitudes of loads when the locations are known. This innovative methodology requires only one strain gauge for each force magnitude desired, reducing the complexity and cost associated with traditional approaches. The theory was verified with laboratory experiments. Seven uniaxial strain gauges were attached to the underside of a simply supported, slender, aluminum beam. One or more loads were applied either directly atop strain gauges or in known positions between strain gauges. Experiments were conducted on several different single and double-load configurations to evaluate the extent of the new methodology which yielded average errors under 5% for the cases where loads were direct atop strain gauges and 6.6% for the cases where the loads were between strain gauges. These findings indicate the potential of this novel strain gauge force transducer to revolutionize load measurement in scenarios where load locations are predetermined.
4
Han, Ji-Hoon, Sung Joon Min, Joon Hyub Kim, and Nam Ki Min. "Reciprocating Arc Silicon Strain Gauges." Sensors 23, no. 3 (January 26, 2023): 1381. http://dx.doi.org/10.3390/s23031381.
Full textAbstract:
Currently, silicon-strain-gauge-based diaphragm pressure sensors use four single-gauge chips for high-output sensitivity. However, the four-single-gauge configuration increases the number of glass frit bonds and the number of aluminum wire bonds, reducing the long-term stability, reliability, and yield of the diaphragm pressure sensor. In this study, a new design of general-purpose silicon strain gauges was developed to improve the sensor output voltage while reducing the number of bonds. The new gauges consist grid patterns with a reciprocating arc of silicon piezoresistors on a thin glass backing. The gauges make handling easier in the bonding process due to the use of thin glass for the gauge backing. The pressure sensors were tested under pressure ranging from 0 to 50 bar at five different temperatures, with a linear output with a typical sensitivity of approximately 16 mV/V/bar and an offset shift of –6 mV to 2 mV. The new approach also opens the possibility to extend arc strain gauges to half-bridge and full-bridge configurations to further reduce the number of glass frit and Al wire bonds in the diaphragm pressure sensor.
5
Korshunov, V., R. Mudrik, D. Ponomarev, and A. Rodionov. "Approaches to refinement of analytical models for stress-strain state assessments of structures based on the analysis of monitoring system data." Transactions of the Krylov State Research Centre 1, no. 395 (March 9, 2021): 47–54. http://dx.doi.org/10.24937/2542-2324-2021-1-395-47-54.
Full textAbstract:
Object and purpose of research. This paper discusses numerical simulation possibilities in terms of stress-strain monitoring for marine engineering structures. This approach can simulate the behavior of strain gauges for both elastic and plastic material behavior. Materials and methods. FEM-based simulation of strain gauge operation process taking into account geometric and physical non-linearity. Main results. Development of refined FE models for sensor installation area of stress-strain monitoring system. Numerical simulation of uniaxial and triaxial strain gauge operation. Time histories of strain gauge readings for linear and non-linear behavior of material. Sensitivity analysis of strain gauges in terms of various strain types. Update of strain gauge arrangement for the best description of structural strains. Conclusion. These results demonstrate and confirm a strong potential of numerical models in development of stress-strain monitoring systems for engineering structures. Simulating strain gauge operation, these models make it possible to determine global strained state of given structure as per strain gauging data for some of its areas.
6
Baker, Spencer A., McKay D. McFadden, Emma E. Bowden, Anton E. Bowden, Ulrike H. Mitchell, and David T. Fullwood. "Accounting for Viscoelasticity When Interpreting Nano-Composite High-Deflection Strain Gauges." Sensors 22, no. 14 (July 13, 2022): 5239. http://dx.doi.org/10.3390/s22145239.
Full textAbstract:
High-deflection strain gauges show potential as economical and user-friendly sensors for capturing large deformations. The interpretation of these sensors is much more complex than that of conventional strain gauges due to the viscoelastic nature of strain gauges. This research endeavor developed and tested a model for interpreting sensor outputs that includes the time-dependent nature of strain gauges. A model that captures the effect of quasi-static strains was determined by using a conventional approach of fitting an equation to observed data. The dynamic relationship between the strain and the resistance was incorporated by superimposing dynamic components onto the quasi-static model to account for spikes in resistances that accompany each change in sensor strain and subsequent exponential decays. It was shown that the model can be calibrated for a given sensor by taking two data points at known strains. The resulting sensor-specific model was able to interpret strain-gauge electrical signals during a cyclical load to predict strain with an average mean absolute error (MAE) of 1.4% strain, and to determine the strain rate with an average MAE of 0.036 mm/s. The resulting model and tuning procedure may be used in a wide range of applications, such as biomechanical monitoring and analysis.
7
Jin, Zhihao, Yuan Li, Dongjue Fan, Caitao Tu, Xuchen Wang, and Shiyong Dang. "Calibration Experiment and Temperature Compensation Method for the Thermal Output of Electrical Resistance Strain Gauges in Health Monitoring of Structures." Symmetry 15, no. 5 (May 11, 2023): 1066. http://dx.doi.org/10.3390/sym15051066.
Full textAbstract:
Electrical resistance strain gauges are widely used in asymmetric structures for measurement and monitoring, but their thermal output in changing temperature environments has a significant impact on the measurement results. Since thermal output is related to the coefficient of thermal expansion of the strain gauge’s sensitive grating material and the measured object, the temperature self-compensation technique of strain gauges fails to eliminate the additional strain caused by temperature because it cannot match the coefficient of thermal expansion of various measured objects. To address this problem, in this study, the principle of the thermal output of electrical resistance strain gauges was analyzed, a calibration experiment for thermal output in the case of a mismatch between the coefficient of linear expansion of the measured object and the strain gauge grating material was conducted, and the mechanism for temperature influence on thermal output was revealed. A method was proposed to obtain the thermal output curves for different materials by using thermostats with dual temperatures to conduct temperature calibration experiments. A linear regression method was used to obtain a linear formula for the thermal output corresponding to each temperature. The thermal output conversion relationship was derived for materials with different coefficients of linear expansion. An in situ temperature compensation technique for electrical resistance strain gauges that separates the measured strain into thermal and mechanical strains was proposed. The results showed that the thermal output curve for the measured object can be calibrated in advance and then deducted from the measured strain, thus reducing the influence of temperature-induced additional strain on the mechanical strain. In addition, a new method was provided for the calculation of the thermal output among materials with similar coefficients of linear expansion, providing a reference for the health monitoring of asymmetric structures.
8
Tutak, Piotr. "Application Of Strain Gauges In Measurements Of Strain Distribution In Complex Objects." Journal of Applied Computer Science Methods 6, no. 2 (December 1, 2014): 135–45. http://dx.doi.org/10.1515/jacsm-2015-0004.
Full textAbstract:
Abstract This article presents an application of strain gauges in measurements of strain which occurs in charge air cooler during the thermal cycle test. The work shows the main idea of measuring system based on strain gauges and important aspects that should be considered when performing measurement. In this article there has been also presented construction and principle operation of a strain gauge measurement system.
9
Alci, Muhsin, and Recep Gunes. "A comparison study on experimental characterization of unidirectional fiber reinforced composites using strain-gauges and virtual extensometers." Materials Testing 65, no. 2 (February 1, 2023): 174–91. http://dx.doi.org/10.1515/mt-2022-0274.
Full textAbstract:
Abstract The aim of this study is to characterize E-glass/epoxy unidirectional fiber reinforced composites using the digital image correlation method with virtual extensometer, which is a less laborious method than strain gauges, compare the results and investigate whether virtual extensometers can be used instead of strain gauges. Measurements in tensile and Iosipescu shear tests were made with both strain gauge and virtual extensometer. Unlike full-field strain measurements in literature, the strains were measured using virtual extensometers. Tensile test and in-plane shear test results gave very consistent results. The differences between the strain gauge and the virtual extensometer for the tensile and in-plane shear tests were less than 3% in the linear region. However, the out-of-plane shear test showed a larger difference of 8.6%. This study showed that the 2D digital image correlation method with virtual extensometers is highly sufficient to find the elasticity moduli and shear moduli in tensile and shear tests in the linear region. In addition, after the damage has started, more measurement data can be obtained with virtual extensometers than with strain gauges.
10
Lin, Fan, Xiaochuan Pan, Chao Wu, Yingjun Zeng, Guochun Chen, Qinnan Chen, Daoheng Sun, and Zhenyin Hai. "ZrB2/SiCN Thin-Film Strain Gauges for In-Situ Strain Detection of Hot Components." Micromachines 13, no. 9 (September 4, 2022): 1467. http://dx.doi.org/10.3390/mi13091467.
Full textAbstract:
The in-situ strain/stress detection of hot components in harsh environments remains a challenging task. In this study, ZrB2/SiCN thin-film strain gauges were fabricated on alumina substrates by direct writing. The effects of ZrB2 content on the electrical conductivity and strain sensitivity of ZrB2/SiCN composites were investigated, and based on these, thin film strain gauges with high electrical conductivity (1.71 S/cm) and a gauge factor of 4.8 were prepared. ZrB2/SiCN thin-film strain gauges exhibit excellent static, cyclic strain responses and resistance stability at room temperature. In order to verify the high temperature performance of the ZrB2/SiCN thin-film strain gauges, the temperature-resistance characteristic curves test, high temperature resistance stability test and cyclic strain test were conducted from 25 °C to 600 °C. ZrB2/SiCN thin-film strain gauges exhibit good resistance repeatability and stability, and highly sensitive strain response, from 25 °C to 600 °C. Therefore, ZrB2/SiCN thin-film strain gauges provide an effective approach for the measurement of in-situ strain of hot components in harsh environments.
11
Carabello, Alina, Constanze Neupetsch, Michael Werner, Christian Rotsch, Welf-Guntram Drossel, and Dirk Zajonz. "Comparison of Resistive and Optical Strain Measurement for Early Fracture Detection." Current Directions in Biomedical Engineering 6, no. 3 (September 1, 2020): 196–99. http://dx.doi.org/10.1515/cdbme-2020-3050.
Full textAbstract:
AbstractTo increase learning success in surgical training, physical simulators are supplemented by measurement technology to generate and record objective feedback and error detection. An opportunity to detect fractures following hip stem implantation early can be measurement of occurring strains on bone surface. These strains can be determined while using strain gauges, digital image correlation (DIC) or photoelasticity. In this research strain gauges and DIC were compared regarding their suitability as strain measurement tools for use in physical simulators. Therefore a testing method was described to replicate the implantation of a hip stem. Testing devices modelled on a realistic prosthesis were pressed into prepared porcine femora in a two-step procedure with a material testing machine. The local strains occurring on bone surface were determined using an optical measurement system for DIC and strain gauges. The initial fractures in the tested femora are located medial-anterior in most cases (73,6%). With increasing indentation depth of the test device, the strains on bone surface increase. Comparing the local strains determined by DIC and strain gauges consistencies in curves are noticeable. Maximal determined strains before fracturing amount to 0,69% with strain gauges and 0,75% with DIC. In the range of the fracture gap, strain gradients are determined by using DIC. However the detected surfaces are of low quality caused by gaps and motion artefacts. The results show strains on bone surfaces for early fracture detection are measurable with strain gauges and DIC. DIC is assessed as less suitable compared to strain gauges. Furthermore strain gauges have greater level of integration and economic efficiency, so they are preferred the use in surgical training simulators.
12
Choquet, P., R. Leroux, and F. Juneau. "New Fabry-Perot Fiber-Optic Sensors for Structural and Geotechnical Monitoring Applications." Transportation Research Record: Journal of the Transportation Research Board 1596, no. 1 (January 1997): 39–44. http://dx.doi.org/10.3141/1596-06.
Full textAbstract:
A new line of fiber-optic sensors suited for structural and geotechnical monitoring purposes is presented. A Fabry-Perot strain gauge is contained in each of the new sensors introduced here: four embedded and surface-type strain gauges and one type of temperature gauge. Described here are the working and reading principles of the basic Fabry-Perot strain gauge. One of the gauge’s features that allows for temperature-compensated or noncompensated measurements is described, and the various sensors constructed around the gauge are presented. These newly developed sensors exhibit high accuracy and repeatability, as illustrated by various calibration tests reported here.
13
Pei, Xue-Yang, Ting-Hua Yi, and Hong-Nan Li. "Dual-type sensor placement optimization by fully utilizing structural modal information." Advances in Structural Engineering 22, no. 3 (September 17, 2018): 737–50. http://dx.doi.org/10.1177/1369433218799151.
Full textAbstract:
Strain gauges and accelerometers are widely used in bridge structural health monitoring systems. Generally, the strain gauges are placed on the key locations to obtain local structural deformation information; the accelerometers are used to obtain the structural modal information. However, the modal information contained in the measured strains is not taken into account. In this article, to fully utilize the modal information contained in strains, a mode shape estimation method is proposed that the strain mode shapes of the strain locations are used to obtain the displacement mode shapes of some positions without accelerometers. At first, to simulate the practical situation, some positions with large structural deformations are selected as the strain gauge locations. Using the proposed mode shape estimation method, the displacement mode shapes of some locations without accelerometers are estimated by the strain mode shapes using the least squares method, and the locations with the smallest estimation error are finally determined as the estimated locations. Then, accelerometers are added to the existing sensor placement. Here, the modal assurance criterion is used to evaluate the distinguishability of the displacement mode shapes obtained from the strain gauges and accelerometers. The accelerometer locations that bring the smallest modal assurance criterion values are selected. In addition, a redundancy can be set to avoid the adjacent sensors containing similar modal information. Through the proposed sensor placement method, the deformation and modal information contained in the strain gauges is fully utilized; the modal information contained in the strain gauges and accelerometers is comprehensively utilized. Numerical experiments are carried out using a bridge benchmark structure to demonstrate the sensor placement method.
14
Graham & White Instruments Ltd. "Weldable strain gauges." NDT & E International 25, no. 1 (January 1992): 54. http://dx.doi.org/10.1016/0963-8695(92)90154-9.
Full text
15
Mathis, Maximilian, Dennis Vollberg, Matthäus Langosch, Dirk Göttel, Angela Lellig, and Günter Schultes. "Creep adjustment of strain gauges based on granular NiCr-carbon thin films." Journal of Sensors and Sensor Systems 10, no. 1 (March 12, 2021): 53–61. http://dx.doi.org/10.5194/jsss-10-53-2021.
Full textAbstract:
Abstract. An important property of high-precision mechanical sensors such as force transducers or torque sensors is the so-called creep error. It is defined as the signal deviation over time at a constant load. Since this signal deviation results in a reduced accuracy of the sensor, it is beneficial to minimize the creep error. Many of these sensors consist of a metallic spring element and strain gauges. In order to realize a sensor with a creep error of almost zero, it is necessary to compensate for the creep behavior of the metallic spring element. This can be achieved by creep adjustment of the used strain gauges. Unlike standard metal foil strain gauges with a gauge factor of 2, a type of strain gauges based on sputter-deposited NiCr-carbon thin films on polymer substrates offers the advantage of an improved gauge factor of about 10. However, for this type of strain gauge, creep adjustment by customary methods is not possible. In order to remedy this disadvantage, a thorough creep analysis is carried out. Five major influences on the creep error of force transducers equipped with NiCr-carbon thin-film strain gauges are examined, namely, the material creep of the metallic spring element (1), the creep (relaxation) of the polymer substrate (2), the composition of the thin film (3), the strain transfer to the thin film (4), and the kind of strain field on the surface of the transducer (5). Consequently, we present two applicable methods for creep adjustment of NiCr-carbon thin- film strain gauges. The first method addresses the intrinsic creep behavior of the thin film by a modification of the film composition. With increasing Cr content (at the expense of Ni, the intrinsic negative creep error can be shifted towards zero. The second method is not based on the thin film itself but rather on a modification of the strain transfer from the polyimide carrier to the thin film. This is achieved by controlled cutting of well-defined deep trenches into the polymer substrate via a picosecond laser.
16
Delyová, Ingrid, Darina Hroncová, Ján Kostka, Vojtech Neumann, and Jana Bokorová. "DETERMINING THE STRAIN SENSITIVITY OF RESISTANCE STRAIN GAUGES." Acta Mechatronica 6, no. 4 (December 31, 2021): 51–56. http://dx.doi.org/10.22306/am.v6i4.79.
Full textAbstract:
When measuring biaxial tension, it is necessary to measure the relative elongation in several directions, for which resistance strain gauges are used. Measurement with resistance strain gauges is based on the change in resistance of the electrical conductor when a deformation occurs. This paper discusses the design of a device for determining the strain sensitivity of resistive strain gauges, which we call the k-factor.
17
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.
Full textAbstract:
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.
18
Kamnik, Rok, Boštjan Kovačič, Andrej Štrukelj, Nikolay Vatin, and Vera Murgul. "Preparation, Installation and Signal Processing of Strain Gauges in Bridge Load Testing." Applied Mechanics and Materials 725-726 (January 2015): 903–12. http://dx.doi.org/10.4028/www.scientific.net/amm.725-726.903.
Full textAbstract:
Practical approach of strain gauges using is introduced. The use of strain gauges and signal processing of measured data at static experimental load testing of a concrete beam are carried out. The ability of the strain gauge sensor to pick up the specific deformation / strain signals during loading is investigated. The Fast Fourier Transformation (FFT) is applied to obtain the signal in frequency domain and reverse FFT to transform the processed signal back to time domain. The measurements are confirmed with some inductive transducers and total station. This approach is tested on 2.7 m long concrete beam in laboratory. A practical use of strain gauges with bridge constructions under complex inspection is described.
19
Brandt, Bjoern, Marion Gemeinert, Ralf Koppert, Jochen Bolte, and Torsten Rabe. "LTCC Substrates for High Performance Strain Gauges." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2012, CICMT (September 1, 2012): 000175–80. http://dx.doi.org/10.4071/cicmt-2012-tp43.
Full textAbstract:
Recent advances in the development of high gauge factor thin-films for strain gauges prompt the research on advanced substrate materials. A glass ceramic composite has been developed in consideration of a high coefficient of thermal expansion and a low modulus of elasticity for the application as support material for thin-film sensors. Constantan foil strain gauges were fabricated from this material by tape casting, pressure-assisted sintering and subsequent lamination of the metal foil on the planar ceramic substrates. The sensors were mounted on a strain gauge beam arrangement and load curves and creep behavior were evaluated. The accuracy of the assembled load cells correspond to accuracy class C6. That qualifies the load cells for the use in automatic packaging units and confirms the applicability of the LTCC substrates for fabrication of accurate strain gauges. To facilitate the deposition of thin film sensor structures onto the LTCC substrates, the pressure-assisted sintering technology has been refined. By the use of smooth setters instead of release tapes substrates with minimal surface roughness were fabricated. Metallic thin films deposited on these substrates exhibit low surface resistances comparable to thin films on commercial alumina thin-film substrates. The presented advances in material design and manufacturing technology are important to promote the development of high performance thin-film strain gauges.
20
LEE, C. S., N. L. WONG, S. SRIGRAROM, and N. T. NGUYEN. "DEVELOPMENT OF 3-COMPONENT FORCE-MOMENT BALANCE FOR LOW SPEED WATER TUNNEL." Modern Physics Letters B 19, no. 28n29 (December 20, 2005): 1575–78. http://dx.doi.org/10.1142/s0217984905009948.
Full textAbstract:
An effort is made to develop a new 3-component force-moment balance, which is capable of measuring lift force, drag force and pitching moment of a model mounted in the water tunnel. The concept used in the balance design is the bending- beam principle. The forces acting on the spring element cause strains on its surface, which are measured by strain gauges. Since strain yielded by the axial force is usually very small, therefore it is not practical to measure axial force using strain gauge directly to sense the strain in axial direction. The main idea of the new balance design is to translate all desired forces (lift and drag) in such a way that they yield bending strain at selected strain-gauge station. This is done by using a bending balance geometry. Under this apparatus, the model wing is mounted at one of its end to the bending balance. The corresponding Lift, Drag forces and Pitching moment are translated into moments at the other end of the balance, and can be measured from sets of strain gauges in bending mode (twisting mode for pitching moment). Example readings are presented in this paper.
21
Fíla, Tomáš, Petr Zlámal, Jan Falta, Tomáš Doktor, Petr Koudelka, Daniel Kytýř, Marcel Adorna, et al. "Testing of Auxetic Materials Using Hopkinson Bar and Digital Image Correlation." EPJ Web of Conferences 183 (2018): 02045. http://dx.doi.org/10.1051/epjconf/201818302045.
Full textAbstract:
In this paper, a split Hopkinson pressure bar (SHPB) was used for impact loading of an auxetic lattice (structure with negative Poisson’s ratio) at a given strain-rate. High strength aluminum and polymethyl methacrylate bars instrumented with foil strain-gauges were used for compression of an additively manufactured missing-rib auxetic lattice. All experiments were observed using a high-speed camera with frame-rate set to approx. 135.000 fps. High-speed images were synchronized with the strain-gauge records. Dynamic equilibrium in the specimen was analyzed and optimized pulse-shaping was introduced in the selected experiments. Longitudinal and lateral in-plane displacements and strains were evaluated using digital image correlation (DIC) technique. DIC results were compared with results obtained from strain-gauges and were found to be in good agreement. Using DIC, it was possible to analyze in-plane strain distribution in the specimens and to evaluate strain dependent Poisson’s ratio of the auxetic structure.
22
Vadivuchezhian, K., K. Subrahmanya, and N. Chockappan. "Finite Element Modeling of Effect of Adhesive Layer and Carrier Thickness Used for Strain Gauge Mounting." Advanced Materials Research 1119 (July 2015): 828–32. http://dx.doi.org/10.4028/www.scientific.net/amr.1119.828.
Full textAbstract:
Metal foil strain gauges are most widely used for the stress analysis in engineering structures. Typical strain gauge system includes strain sensitive grid, carrier material, and adhesive layer. Strain measurement from the strain gauge is partially affected by carrier and adhesive materials and their thickness. In the present work, a Finite Element Model is developed in order to study the effect of both adhesive layer and carrier thickness on strain measurements while using strain gauges. To understand the behavior of the adhesive material, mechanical characterization is done on bulk adhesive specimen. Finite Element Analysis (FEA) is carried out with different materials namely epoxy and polyurethane. Initially a single element foil loop is considered for the analysis and further this is extended to metal foil strain gauge with nine end-loops. Finally, the strain variation through thickness of adhesive layer, carrier and strain sensitive grid is obtained from FEA. The results thus obtained are compared with analytical results from Basic Strength of Materials approach.
23
Gower, Michael R. L., and Richard M. Shaw. "Towards a Planar Cruciform Specimen for Biaxial Characterisation of Polymer Matrix Composites." Applied Mechanics and Materials 24-25 (June 2010): 115–20. http://dx.doi.org/10.4028/www.scientific.net/amm.24-25.115.
Full textAbstract:
This paper details work undertaken towards the development of a standard test method for the biaxial response of planar cruciform specimens manufactured from carbon fibre-reinforced plastic (CFRP) laminates and subject to tension-tension loading. Achieving true biaxial failure in a cruciform specimen without the need for the inclusion of a stress raiser, such as a hole, in the gauge-section, is a subject attracting much research globally and is by no means a trivial exercise. Coupon designs were modelled using finite element analysis (FEA) in order to predict the stress and strain distributions in the central region of the specimen. An Instron biaxial strong-floor test machine was used to test the specimens. Strain gauges were used to measure the strain in the specimen arms and to assess the degree of bending. Digital image correlation (DIC) was used to measure the full-field strain distribution in the central gauge-section of the specimen and this was compared to values measured using strain gauges. The strain readings obtained from strain gauges, DIC and FEA predictions were in good agreement and showed that the strain distribution was uniform in the central gauge-section, but that strain concentrations existed around the tapered thickness zone. These regions of strain concentration resulted in interlaminar failure and delamination of the laminate propagating into the specimen arms.
24
Maiwald, M., C. Werner, V. Zoellmer, and M. Busse. "INKtelligent printed strain gauges." Sensors and Actuators A: Physical 162, no. 2 (August 2010): 198–201. http://dx.doi.org/10.1016/j.sna.2010.02.019.
Full text
25
Maiwald, M., C. Werner, V. Zoellmer, and M. Busse. "INKtelligent printed strain gauges." Procedia Chemistry 1, no. 1 (September 2009): 907–10. http://dx.doi.org/10.1016/j.proche.2009.07.226.
Full text
26
Piech, T., and H. D. Tietz. "Barkhausen-noise strain gauges." NDT & E International 24, no. 1 (February 1991): 47. http://dx.doi.org/10.1016/0963-8695(91)90783-y.
Full text
27
Klokova, N. P. "Strain gauges of TsAGI." Measurement Techniques 37, no. 10 (October 1994): 1164–69. http://dx.doi.org/10.1007/bf00978849.
Full text
28
Zimin, V. N., N. Z. Salakhov, and N. A. Shelepin. "Integrated beam strain gauges." Measurement Techniques 37, no. 3 (March 1994): 300–302. http://dx.doi.org/10.1007/bf02614268.
Full text
29
Klaas, Daniel, Rico Ottermann, Folke Dencker, and Marc Christopher Wurz. "Development, Characterisation and High-Temperature Suitability of Thin-Film Strain Gauges Directly Deposited with a New Sputter Coating System." Sensors 20, no. 11 (June 10, 2020): 3294. http://dx.doi.org/10.3390/s20113294.
Full textAbstract:
New sensor and sensor manufacturing technologies are identified as a key factor for a successful digitalisation and are therefore economically important for manufacturers and industry. To address various requirements, a new sputter coating system has been invented at the Institute of Micro Production Technology. It enables the deposition of sensor systems directly onto technical surfaces. Compared to commercially available systems, it has no spatial limitations concerning the maximum coatable component size. Moreover, it enables a simultaneous structuring of deposited layers. Within this paper, characterisation techniques, results and challenges concerning directly deposited thin film strain gauges with the new sputter coating system are presented. Constantan (CuNiMn 54/45/1) and NiCr 80/20 are used as sensor materials. The initial resistance, temperature coefficient of resistance and gauge factor/k-factor of quarter-bridge strain gauges are characterised. The influence of a protective layer on sensor behaviour and layer adhesion is investigated as well. Moreover, the temperature compensation quality of directly deposited half-bridge strain gauges is evaluated, optimised with an external trimming technology and benchmarked against commercial strain gauges. Finally, the suitability for high-temperature strain measurement is investigated. Results show a maximum operation temperature of at least 400 °C, which is above the current state-of-the-art of commercial foil-based metal strain gauges.
30
Kuzmych, L. "Synthesis of Measurement Method of Stressed — Deformed Condition of Complex Structures." Metrology and instruments, no. 3 (July 3, 2019): 12–18. http://dx.doi.org/10.33955/2307-2180(3)2019.12-18.
Full textAbstract:
Nowadays the most common instruments of measuring the stress-strain state of complex structures are strain gauges. As a rule, strain gages are connected to the measuring system according to the bridge scheme, it provides elimination of systematic errors of measurement and compensation of temperature deformations. The principles of constructing, designing and mathematical modeling of deformation and stresses of complex technical constructions with the help of strain gauges taking into account destabilizing factors are developed, which allows to significantly reduce the level of errors in relation to existing methods of measurement and known analogues.
The analysis of the main destabilizing factors that limit the accuracy of measurement using strain gauge is carried out, are (Fig. 1—4):
the random processes (noises, obstacles, etc.);
the time changes of parameters of measuring transducers due to aging and physical degradation;
the influence of external climatic and mechanical factors (temperature, humidity, etc.).
The temperature error values are set for the most common alloys used for the manufacture of strain gauges, namely: constantan and karma.
This work is aimed at finding ways to improve the accuracy of remote measurements and impedance of measuring devices of the stress — strain state, in particular strain gauges and strain gauges, by introducing improved theoretical calculations taking into account destabilizing factors, which makes it possible to reduce the level of errors with respect to known analogs in dozens of times.
31
Mathis, Maximilian, Dennis Vollberg, Matthäus Langosch, Dirk Göttel, Angela Lellig, and Günter Schultes. "Novel method to reduce the transverse sensitivity of granular thin film strain gauges by modification of strain transfer." Journal of Sensors and Sensor Systems 9, no. 2 (July 17, 2020): 219–26. http://dx.doi.org/10.5194/jsss-9-219-2020.
Full textAbstract:
Abstract. Strain gauges based on polyimide carrier foils and piezoresistive granular thin films are highly sensitive to strain. Unlike conventional metal foil, granular film strain gauges also have a pronounced sensitivity to strain acting in the transverse direction. A novel method that allows for the modification of the strain transfer is proposed and proven experimentally. The method is based on the creation of stand-alone polyimide paths, on top of which the piezoresistive thin film is located. In this way, the granular film hardly receives any transverse strain; hence, the transverse sensitivity is drastically reduced. A picosecond laser system can be used for both patterning of the thin film and for controlled ablation of polyimide in order to generate well-defined high path structures. The working principle of the method is demonstrated by simulation, followed by an experimental verification using measurements of the transverse gauge factor. Furthermore, the output signal of force transducers may be increased using granular thin film strain gauges of reduced transverse sensitivity.
32
Peng, Lu, Genqiang Jing, Zhu Luo, Xin Yuan, Yixu Wang, and Bing Zhang. "Temperature and Strain Correlation of Bridge Parallel Structure Based on Vibrating Wire Strain Sensor." Sensors 20, no. 3 (January 24, 2020): 658. http://dx.doi.org/10.3390/s20030658.
Full textAbstract:
Deformation is a ubiquitous phenomenon in nature. This process usually refers to the change in shape, size, and position of an object in the time and spatial domain under various loads. Under normal circumstances, during engineering construction, technicians are generally required to monitor the safe operation of structural facilities in the transportation field and the health of bridge, because monitoring in the engineering process plays an important role in construction safety. Considering the reliability risk of sensors after a long-time work period, such as signal drift, accurate measurement of strain gauges is inseparable from the value traceability system of high-precision strain gauges. In this study, two vibrating wire strain gauges with the same working principle were measured using the parallel method at similar positions. First, based on the principle of time series, the experiment used high-frequency dynamic acquisition to measure the thermometer strain of two vibrating wire strain gauges. Second, this experiment analyzed the correlation between strain and temperature measured separately. Under the condition of different prestress, this experiment studied the influencing relationship of temperature corresponding variable. In this experiment, the measurement repetitiveness was analyzed using the meteorology knowledge of single sensor data, focused on researching the influence of temperature and prestress effect on sensors by analyzing differences of their measurement results in a specified situation. Then, the reliability and stability of dynamic vibrating wire strain gauge were verified in the experiment. The final conclusion of the experiment is the actual engineering in the later stage. Onsite online meteorology in the application provides support.
33
Huang, Y. H., L. Liu, F. C. Sham, Y. S. Chan, and S. P. Ng. "Optical strain gauge vs. traditional strain gauges for concrete elasticity modulus determination." Optik 121, no. 18 (October 2010): 1635–41. http://dx.doi.org/10.1016/j.ijleo.2009.03.002.
Full text
34
Marcinczak, Dorota, and Tomasz Trapko. "DIC (Digital Image Correlation) method in the research of RC beams strengthened with PBO-FRCM materials." E3S Web of Conferences 97 (2019): 03008. http://dx.doi.org/10.1051/e3sconf/20199703008.
Full textAbstract:
The article presents tests of a reinforced concrete beam strengthened in a shear with PBO-FRCM composite materials. Measurement of the deformation of the composite was carried out using two methods - with strain gauges and the optical DIC method (Digital Image Correlation). The DIC method consists in taking a series of photographs of the tested object before and during loading. The surface of the tested element must have randomly spaced spots that are applied to the object before measurement. During the study, the cameras monitor the shifting of spots against each other, which in comparison to the reference image before loading gives information about strains and stresses of the tested element. Measurements of deformation of composite materials using strain gauges are difficult to clearly analyse, because the strain gauge is in a specific, limited place, which does not correspond to the work of the entire composite. In addition, the strain gauge tends to break at the place of crack. The article discusses this problem by presenting the results of deformation of PBO-FRCM composite meshes measured in two mentioned ways, their comparison and discussion of results.
35
Woszczyński, Mariusz, Joanna Rogala-Rojek, and Krzysztof Stankiewicz. "Advancement of the Monitoring System for Arch Support Geometry and Loads." Energies 15, no. 6 (March 18, 2022): 2222. http://dx.doi.org/10.3390/en15062222.
Full textAbstract:
As part of the RFCS project, which aimed to improve transport safety in mines, ITG KOMAG proposed a system for monitoring loads and geometric of arch support. The system’s function is to control safety, mainly during suspended monorail runs. This paper presents a hardware model and a measurement method based on the use of vibrating wire strain gauges and draw-wire sensors. The challenge was to properly adapt the vibrating wire strain gauge operation to the requirements of the ATEX directive on the safe use of electrical equipment in underground mines. The signal transducer algorithm and potential mounting locations for the proposed sensors were discussed. The results of tests carried out using the ŁP arc support are presented, reflecting the actual behavior of the casing during loading in accordance with the test methodology proposed by the Central Mining Institute. In order to compare the results with another measurement method, film strain gauges were additionally applied. The results confirm the usefulness of the proposed method for testing in real conditions. The speed and simplicity of installation of vibrating wire strain gauges provides an advantage over the use of film strain gauges, which are very difficult to install in underground conditions.
36
Chen, Xiyuan, Tanay Topac, Wyatt Smith, Purim Ladpli, Cheng Liu, and Fu-Kuo Chang. "Characterization of Distributed Microfabricated Strain Gauges on Stretchable Sensor Networks for Structural Applications." Sensors 18, no. 10 (September 28, 2018): 3260. http://dx.doi.org/10.3390/s18103260.
Full textAbstract:
Smart structures mimic biological systems by using thousands of sensors serving as a nervous system analog. One approach to give structures this sensing ability is to develop a multifunctional sensor network. Previous work has demonstrated stretchable sensor networks consisting of temperature sensors and impact detectors for monitoring external environments and interacting with other objects. The objective of this work is to develop distributed, robust and reliable strain gauges for obtaining the strain distribution of a designated region on the target structure. Here, we report a stretchable network that has 27 rosette strain gauges, 6 resistive temperature devices and 8 piezoelectric transducers symmetrically distributed over an area of 150 × 150 mm to map and quantify multiple physical stimuli with a spatial resolution of 2.5 × 2.5 mm. We performed computational modeling of the network stretching process to improve measurement accuracy and conducted experimental characterizations of the microfabricated strain gauges to verify their gauge factor and temperature coefficient. Collectively, the results represent a robust and reliable sensing system that is able to generate a distributed strain profile of a common structure. The reported strain gauge network may find a wide range of applications in morphing wings, smart buildings, autonomous cars and intelligent robots.
37
Schmaljohann, F., D. Hagedorn, and F. Löffler. "Thin film sensors for measuring small forces." Journal of Sensors and Sensor Systems 4, no. 1 (February 23, 2015): 91–95. http://dx.doi.org/10.5194/jsss-4-91-2015.
Full textAbstract:
Abstract. Especially in the case of measuring small forces, the use of conventional foil strain gauges is limited. The measurement uncertainty rises by force shunts and is due to the polymer foils used, as they are susceptible to moisture. Strain gauges in thin film technology present a potential solution to overcome these effects because of their direct and atomic contact with the measuring body, omitting an adhesive layer and the polymer foil. For force measurements up to 1 N, a suitable deformation element was developed by finite element (FE) analysis. This element is designed for an approximate strain of 1000 μm m−1 at the designated nominal load. The thin film system was applied by magnetron sputtering. The strain gauge structure is fabricated by distinct photolithographic steps. The developed sensors were tested with different load increments. The functional capability of the single resistance strain gauges could be proven. Moreover, a developed sensor in a full bridge circuit showed a linear characteristic with low deviation and good stability.
38
Ballivy, Gérard, Brahim Benmokrane, and Omar Chaallal. "Déformations générées dans les bétons sous l'influence des conditions climatiques." Canadian Journal of Civil Engineering 18, no. 6 (December 1, 1991): 1088–92. http://dx.doi.org/10.1139/l91-132.
Full textAbstract:
This paper presents the results of an experimental study of strains generated in concrete by variations in climatic conditions. Three 0.16 m3 concrete blocks, instrumented with vibrating wires strain gauges, were exposed to various environmental conditions (drying–wetting) during approximately 3 years and strains were measured. The study shows that concrete strains induced by environmental agents acting alone can reach levels that may jeopardize the structural integrity of concrete structures exposed to similar conditions, when the boundary conditions cannot accommodate the resulting extensive volume changes. Key words: environmental conditions, relative humidity, temperature, drying, wetting, vibrating wires strain gauge, concrete strains.
39
Kuvandykov, R. E. "On the Possibility of Using the Strain-Frequency Method for Measuring the Absolute Gas Pressure in Reference Vacuum Gauges." Measurement Standards. Reference Materials 18, no. 3 (December 30, 2022): 17–28. http://dx.doi.org/10.20915/2077-1177-2022-18-3-17-28.
Full textAbstract:
An especially important direction in metrological science is ensuring the accuracy of vacuum measurements, which is crucial for industry. In Russia, predominantly foreign vacuum gauges with a vacuum measurement range PNPI – PVPI 0.1–1000 Pa are used as reference vacuum gauges for verification and calibration of vacuum gauges. On the basis of the analysis of the characteristics of reference vacuum gauges used in Russia based on various methods for measuring gas pressure, it can be argued that the most accurate and common measurement method among reference vacuum gauges is the strain method. However, the strain method has a number of limitations associated with the need to introduce the following corrections: correction for the residual pressure in the comparative chamber, correction for the influence of temperature effects during temperature control of the primary measuring transducer. The purpose of this work was to study the compliance of the metrological characteristics of a vacuum gauge based on a new strain-frequency method for measuring the absolute gas pressure with the requirements for reference vacuum gauges given in state verification schemes in the field of vacuum measurements.The main research methods were the study of the metrological characteristics of the strain-frequency vacuum gauge, taking into account the correction for the residual pressure in the comparative chamber; corrections for the influence of temperature effects during temperature control of the primary measuring transducer, as well as for the compliance of the method with the requirements of state verification schemes in the field of vacuum measurements. An assessment of the accuracy indicators of the strain-frequency method for measuring the absolute gas pressure based on the analysis of the measurement equation, taking into account the assessment of the components of the uncertainty sources, is given. The obtained results have shown the possibility of using the strain-frequency method of pressure measurement, with the exception of the correction for the residual pressure in the comparative chamber, corrections for the influence of temperature effects during temperature control of the primary measuring transducer in reference vacuum gauges that meet the requirements of state verification schemes in the field of vacuum measurements.As a result of the study, it was found that the expanded uncertainty of the result of measuring pressure with a vacuum gauge based on the new strain-frequency method does not exceed 2 %. This makes it possible to use this method in reference vacuum gauges.The practical significance of the developed scientific and methodological principles, and technological solutions for calculating and manufacturing the primary measuring transducer of a vacuum gauge based on a new method for measuring low absolute pressure lies in the possibility to manufacture the primary measuring transducer at Russian enterprises using domestic technologies of microsystem technology.
40
Zhavyrkin, V. V., and L. A. Sladkova. "Three-component strain gauge for precise measurement of load fluctuations." iPolytech Journal 27, no. 2 (July 7, 2023): 241–49. http://dx.doi.org/10.21285/1814-3520-2023-2-241-249.
Full textAbstract:
The aim was to assess the loading of large-size elements of machine structures using versatile strain gauges. A strain gauge was developed using a system analysis of failures and deficiencies in the manufacture and operation of large-scale structures, strain gauging, strength of materials methods, as well as the theory of elasticity of ring elastic elements. The ANSIS software package was used to calculate rational sensor parameters. The conducted study of ring elastic deformation (determination of stiffness and stress-strain state) allowed the authors to propose that the ring shape should be replaced by an octahedral polygon. This form is suitable for mounting strain gauges for simultaneous measurement of tension and compression, as well as bending and torsion, i.e., forces arising in a machine structural element or in the manufacture of large-size surfaces. The obtained results were used to derive dependences to determine the measurement error of the gauge under study. A comparative analysis of ring and octahedral gauges identified unique features of the latter, consisting in the possibility of assessing the measured values along the three coordinate axes with a high degree of accuracy. The conducted research shows that the proposed strain gauges are capable of registering the magnitude and fluctuations of loads with a high measurement accuracy. The proposed scheme of gauge placement makes it possible to determine the vertical and horizontal components of the forces arising in a structural element and to assess deviations in the process of measurement. In addition, the proposed measuring scheme minimizes the error of mutual influence of sensors. The developed force meter is a versatile device that can be used for registering static and dynamic impacts, as well as for digital control of force parameters in the range of up to 5 mm.
41
Zeiser, Roderich, Suleman Ayub, Jochen Hempel, Michael Berndt, and Juergen Wilde. "Mechanical Stress Analyses of Packaged Pressure Sensors for Very High Temperatures." Journal of Microelectronics and Electronic Packaging 11, no. 1 (January 1, 2014): 30–35. http://dx.doi.org/10.4071/imaps.399.
Full textAbstract:
Methods for investigations of stresses specialized for devices operating up to 500°C are presented in this study. Resistive pressure sensors and test chips with microstrain (μ-strain) gauges are processed in thin film technology. The sensor structure was a Wheatstone bridge on a silicon membrane with platinum resistors. The μ-strain gauges were characterized with tensile tests in combination with optical strain measurements. A gauge factor of 3.6 was measured at room temperature. After characterization as bare dice, the chips were mounted with a borosilicate glass solder on two ceramic substrates, AlN and Si3N4. We generated a FE model of the sensor assemblies including temperature-dependent material properties. The distribution of mechanical strains and stresses in the sensor was analyzed. The chip warpage dependent on temperature up to 500°C was obtained from FE simulations and compared with high-precision 3D deformation measurements. Deformation results from digital image correlation (DIC) verified the utilized FE model. The correlation of experimental results for the chip warpage exhibited good agreement with the numerical results obtained from FEM. The chip deflection from the center to the edges in the out-of-plane direction on AlN was 4.5 μm; on Si3N4 a concave warpage of 3 μm at 25°C was found. Temperature-induced deformations of the sensor chip in the range of micrometers were recorded up to 500°C. The output signal of the pressure sensors is strongly affected by superimposed strains based on the sensor assembly. The bridge voltage increased by 40% after the glass solder process on AlN and by 34% for devices on Si3N4. The analysis of the μ-strain gauges showed compressive strains in the sensor membrane of −1.39% on average for assemblies on AlN and of −0.168% for glass soldered chips on Si3N4. The FEM simulations revealed an average in-plane stress in the sensor membrane of −45 MPa for chips on AlN and −20 MPa for Si3N4 substrates. The compressive strains in the membrane obtained by FEM were verified by the μ-strain gauge measurements. A higher strain and stress gradient in the membrane of devices on AlN was found with FEM, which is consistent with the higher signal offset of assembled pressure sensors that was measured in this study.
42
Kawahara, Takamasa, and Toshiaki Tsuji. "Development of High Dynamic Range Six-Axis Force Sensor with Simple Structure." Journal of Robotics and Mechatronics 35, no. 3 (June 20, 2023): 771–79. http://dx.doi.org/10.20965/jrm.2023.p0771.
Full textAbstract:
We propose a six-axis force sensor with a simple structure that can measure small forces while affording a high load capacity. For a robot to perform complex motions in an unknown environment, the force sensor used must exhibit a high resolution and high load rating. Various studies have been conducted to simultaneously satisfy these two requirements. However, the high processing cost due to the complicated sensor structure is problematic. Therefore, we develop a column-type high dynamic range (HDR) six-axis force sensor using two types of strain gauges. The sensor was composed of a drawn pipe to solve structural problems that arise during manufacturing. By attaching strain gauges to the surface of the drawn pipe, the forces and torques in the six axes can be measured. HDR measurement was realizable using a semiconductor strain gauge for small loads and a metallic foil strain gauge for large loads. Based on the simulation results, the rated loads of the sensor were 1400 N in the Fx and Fy directions, 9000 N in the Fz direction, and 120 Nm in the Mx, My, and Mz directions. The performance of the fabricated force sensor was evaluated. The maximum nonlinearity errors of the semiconductor strain gauge and the metallic foil strain gauges were 1.21% and 1.81%, respectively. In addition, when comparing the S/N ratios, the minimum measurable values were 0.035 N and 0.13 N for Fy and Fz, respectively.
43
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.
Full textAbstract:
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.
44
Vilayvong, K., N. Yasufuku, and R. Ishikura. "Evaluation of rainfall erosivity and impact forces using strain gauges." Lowland Technology International 17, no. 4 (2016): 207–17. http://dx.doi.org/10.14247/lti.17.4_207.
Full text
45
Kim, Joon Hyub, Ji-Hoon Han, Chan Won Park, and Nam Ki Min. "Enhancement of Withstand Voltage in Silicon Strain Gauges Using a Thin Alkali-Free Glass." Sensors 20, no. 11 (May 26, 2020): 3024. http://dx.doi.org/10.3390/s20113024.
Full textAbstract:
We present a cost-effective approach to produce silicon strain gauges that can withstand very high voltage without using any complex package design and without sacrificing any sensor performance. This is achieved by a special silicon strain gauge structure created on an alkali-free glass substrate that has a high breakdown voltage. A half-bridge silicon strain gauge is designed, fabricated, and then tested to measure its output characteristics. The device has a glass layer that is only 25–55 µm thick; it shows it is able to withstand a voltage of over 2000 V while maintaining a high degree of linearity with correlation coefficients higher than 0.9990 and an average sensitivity of 104.13. Due to their unique electrical properties, silicon strain gauges-on-glass chips hold much promise for use in advanced force and pressure sensors.
46
Elsayed, M. M., M. O. Hendy, and E. E. El Soally. "A new approach for the determination of residual stresses in biaxially stressed plates." Journal of Strain Analysis for Engineering Design 28, no. 3 (July 1, 1993): 181–86. http://dx.doi.org/10.1243/03093247v283181.
Full textAbstract:
This paper presents a modified hole-drilling technique for measuring residual stresses in a finite width plate subjected to biaxial tensile loading. Instead of using a special strain rosette containing three elements, only two strain gauges are used to determine the values of relaxed strains and hence the residual stresses in a biaxially stressed plate. It also gives a new approach which measures the radial relieved strains in two strain gauges mounted on a plate due to drilling a small central hole and then enlarging it. The corresponding residual stresses and their directions are derived.
47
Zhao, Yinming, Zhigang Wang, Siyang Tan, Yang Liu, Si Chen, Yongqian Li, and Qun Hao. "Dependance of Gauge Factor on Micro-Morphology of Sensitive Grids in Resistive Strain Gauges." Micromachines 13, no. 2 (February 10, 2022): 280. http://dx.doi.org/10.3390/mi13020280.
Full textAbstract:
The effect of micro-morphology of resistive strain gauges on gauge factor was investigated numerically and experimentally. Based on the observed dimensional parameters of various commercial resistive strain gauges, a modeling method had been proposed to reconstruct the rough sidewall on the sensitive grids. Both the amplitude and period of sidewall profiles are normalized by the sensitive grid width. The relative resistance change of the strain gauge model with varying sidewall profiles was calculated. The results indicate that the micro-morphology on the sidewall profile led to the deviation of the relative resistance change and the decrease in gauge factor. To verify these conclusions, two groups of the strain gauge samples with different qualities of sidewall profiles have been manufactured, and both their relative resistance changes and gauge factors were measured by a testing apparatus for strain gauge parameters. It turned out that the experimental results are also consistent with the simulations. Under the loading strain within 1000 μm/m, the average gauge factors of these two groups of samples are 2.126 and 2.106, respectively, the samples with rougher profiles have lower values in gauge factors. The reduction in the gauge factor decreases the sensitivity by 2.0%. Our work shows that the sidewall micro-morphology on sensitive grids plays a role in the change of the gauge factor. The observed phenomena help derive correction methods for strain gauge measurements and predict the measurement errors coming from the local and global reinforcement effects.
48
Marcińczak, Dorota. "Metoda DIC." BUILDER 259, no. 2 (February 1, 2019): 66–68. http://dx.doi.org/10.5604/01.3001.0013.3444.
Full textAbstract:
DIC (DIGITAL IMAGE CORRELATION) METHOD IN THE RESEARCH OF RC BEAMS STRENGTHENED WITH PBOFRCM MATERIALS. The article presents tests of a reinforced concrete beam strengthened in a shear with PBO-FRCM composite materials. Measurement of the deformation of the composite was carried out using two methods - with strain gauges and the optical DIC method (Digital Image Correlation). The DIC method consists in taking a series of photographs of the tested object before and during loading. The surface of the tested element must have randomly spaced spots that are applied to the object before measurement. During the study, the cameras monitor the shifting of spots against each other, which in comparison to the reference image before loading gives information about strains and stresses of the tested element. Measurements of deformation of composite materials using strain gauges are difficult to clearly analyze, because the strain gauge is in a specific, limited place, which does not correspond to the work of the entire composite. In addition, the strain gauge tends to break at the place of crack. The article discusses this problem by presenting the results of deformation of PBO-FRCM composite meshes measured in two mentioned ways, their comparison and discussion of results.
49
Schembri, Tyler, Silvia Tejedor, and Claire Davis. "Strain Measurements Using Fibre Bragg Gratings during Full-Scale Structural Testing of an F/A-18 Centre Barrel." Key Engineering Materials 558 (June 2013): 510–21. http://dx.doi.org/10.4028/www.scientific.net/kem.558.510.
Full textAbstract:
This paper reports on an experimental program of work which investigates the use of fibre Bragg gratings (FBGs) for the measurement of surface strains during full-scale structural testing. The test article was an ex-service F/A-18 wing attachment centre barrel (CB). The CB has three main structural bulkheads whose function is to carry wing loads into the fuselage. Two FBGs were surface mounted to each bulkhead on the starboard side with electrical resistance foil strain gauges bonded to symmetric locations on the port side of the structure for comparison. The FBGs were fabricated during the fibre draw process and were then packaged in a composite tape for secondary bonding to the structure under test using a standard aerospace qualified strain gauge adhesive. The centre barrel was subjected to a series of load surveys comprising 50%, 70% and 100% of the maximum spectrum load amplitude and low constant amplitude (8% of maximum spectrum load) cycling during thermoelastic stress analysis surveys prior to the initiation of variable amplitude accelerated fatigue spectrum loading until structural failure. The experimental data shows good agreement between the electrical-resistance foil and optical gauges when the loading is symmetric with additional detail provided by the optical gauges which had a higher sampling rate. These results confirm the potential of FBGs to provide detailed experimental strain data from across the structure without the associated complexity of wiring and installation often associated with electrical foil gauges.
50
San Román, J. L., C. Álvarez-Caldas, and A. Quesada. "Structural Validation of Railway Bogies and Wagons Using Finite Elements Tools." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 219, no. 3 (May 1, 2005): 139–50. http://dx.doi.org/10.1243/095440905x8844.
Full textAbstract:
This article aims to contribute an integrated solution for the design and test of railway bogies, so that the demands of each new design can be validated by computing. Nowadays, official approval regulations demand experimental tests on real prototypes. Three different kinds of tests are required. Trying to substitute these tests by simulations on a finite element method (FEM) model, two main troubles appear. (1) Strain gauges used in experimental tests must be substituted by a FEM entity that provides similar results as long as official standard regulations can be applied to them. (2) Current FEM codes present several problems simulating fatigue phenomenon. In this article, a new type of finite element, called virtual strain gauge, is proposed. Results obtained by this element can be treated as experimental results, as long as they are much similar to strain gauges results than other typical FEM ones. Fatigue testing may be reduced when greater experience is acquired with virtual strain gauges. However, it will always play a key role in final test with real prototypes, pinpointing errors in materials, manufacture, and welding. This work concludes that, using virtual strain gauges, experimental tests can be drastically reduced by replacing them with FEM simulations. An example of an MSP railway bogie is analysed to illustrate theoretical results.