Strain gauges

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A study of strain and deformation measurement using the Arduino microcontroller and strain gauges devices

A study of strain and deformation measurement using the Arduino microcontroller and strain gauges devices

After the preparation process for the strain gauge bonding, the bonding process begins. For this, it is needed a glass base, previously cleaned with alcohol, tweezers, transparent tape and instant glue. To better handle the strain gauge with the tweezers, place it on the glass base so that its grid and solder terminals are up, note that the strain gauges should only be handled using the tweezers, avoiding any contact with the hands, reducing any risk of damage in them. Besides, the oiliness that is present in the hand can cause the oxidation of the strain-gauge grid. With the transparent tape glue the strain gauge onto the glass base. When removing the tape the strain gauge must be removed with the tape, still glued in it. The bonding of the strain-gauge to the tape is performed to facilitate the correct positioning and bonding of the transducer to the surface where the deformation will be measured. The tape and the strain gauge must be carefully positioned on the surface so that the previously marked lines match the strain gauge indicators. Figure 6 illustrates the correct positioning of the strain gauge. After the correct positioning, one must carefully peel off part of the tape until the strain gauge is raised to insert a small amount of instant glue under it, quickly reposition the tape as before and press the strain gauge so that bubbles do not form under it. Again, in applications where higher precision is required, it might be necessary to use specific products and more elaborate processes for bonding. After the cure time of the adhesive, carefully remove the tape and inspect the strain gauge with a magnifying glass. If the strain gauge has bubbles under its surface or if it is incorrectly positioned, remove it, discard it, and perform the preparation and gluing procedures again.
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J. Appl. Oral Sci.  vol.18 número2

J. Appl. Oral Sci. vol.18 número2

bjective: This study aimed to evaluate the bending moments, and compressive and tensile forces in implant-supported prostheses with three, four or five abutments. Material and Methods: Ten Pd-Ag frameworks were tested over two master models with: 1) parallel vertical implants, and 2) tilted distal implants. Strain gauges were fixed on the abutments of each master model to measure the deformation when a static load of 50 N was applied on the cantilever (15 mm). The deformation values were measured when the metallic frameworks were tested over three, four or five abutments, and transformed into force and bending moment values. Data were analyzed by ANOVA and Tukey’s test for multiple comparisons at 5% level of significance. Results: Abutment #1 (adjacent to the cantilever) had the highest values of force and sagittal bending moment for all tests with three, four or five abutments. Independently from the number of abutments, axial force in abutment #1 was higher in the vertical model than in the tilted model. Total moment was higher with three abutments than with four or five abutments. Independently from the inclination of implants, the mean force with four or five abutments was lower than that with three abutments. Conclusion: The results suggest that in the set-ups with four or five abutments tilted distal implants reduced axial force and did not increase bending moments.
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Comprehensive study of endurance for IAR-99 Hawk

Comprehensive study of endurance for IAR-99 Hawk

recorded by flight or fatigue parameters counters. The installation of a strain gauge is made using a pattern (its position and orientation are crucial) and the strain gauge selected for installation should not be fragile or unstable. Routines should be established for periodic inspection of strain gauges and those which are defective should be replaced immediately.

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Mechanical evaluation of bone gap filled with rigid formulations castor oil polyurethane and chitosan in horses

Mechanical evaluation of bone gap filled with rigid formulations castor oil polyurethane and chitosan in horses

Often fractures of long bones in horses are comminuted and form bone gaps, which represent a major challenge for the fixation of these fractures by loss of contact between the fragments. Bone grafts help in treating this kind of fracture and synthetic materials have been gaining ground because of the limitations of autologous and heterologous grafts. In this study were performed compressive non destructive test in 10 bones with complete cross- bone gap in mid-diaphyseal of the third metacarpal bone of horses. Using a mechanism of “crossing” the 10 bones were used in the three groups (control, castor oil poliuretane and chitosan) according to the filling material. After the test with maximum load of 1000N bone had a gap filled by another material and the test was repeated. Deformations caused on the whole bone, plate and bone tissue near and distant of gap were evaluated, using strain gauges adhered to the surface at these locations. There was a reduction in bone deformation from 14% (control) to 3,5% and 4,8% by filling the gap with Chitosan and castor oil respectively, and a reduction of strain on the plate of 96% and 85% by filling gap with chitosan and castor respectively. An increase in intensity and direction of deformations occurred in bone near to gap after its filling; however, there was no difference in bone deformations occurring far the gap.
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The U-tube: A New Paradigm for Borehole Fluid Sampling

The U-tube: A New Paradigm for Borehole Fluid Sampling

In contrast to the simplicity of the downhole U-tube system, the surface processing of the recovered luids was quite complex. The U-tube surface completion consisted of six different manifold assemblies, allowing for careful control of sampling conditions and complete system purging between samplings. To facilitate reproducible sampling and minimize the potential for operator error, the sampling operation was automated with pneumatically operated valves. Control software was developed using the graphical programming language Labview (National Instruments, Austin, Texas, U.S.A.). Figure 2A shows the four 13 L sample vessels along with associated valving and gauges, with strain gauges mounted at the base of each cylinder to measure the bulk
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Introduction of the Chair of IEEE-EMBS Portuguese Chapter

Introduction of the Chair of IEEE-EMBS Portuguese Chapter

Abstract— In this study, a three-dimensional dynamic model was built to simulate the drilling process in the composite materials. With an explicit dynamic simulation it is possible to obtain large structural deformation and to apply high intensity loading in a short time frame. Using this methodology, the influence of different cutting parameters were considered during the drilling process in typical composite materials. Also, similar tests were produced in laboratory using composite blocks. Each composite material was instrumented with strain gauges to obtain the strain in different surface positions during the drilling process. The results from the numerical methodology were compared with the experimental methodology. It was concluded when the feed-rate is higher the stresses and strains in the composite material are lower. The obtained numerical and experimental results were similar. Therefore the developed numerical model proved to be a great tool in this kind of analysis.
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An experimental study on flexural strength enhancement  of concrete by means of small steel fibers

An experimental study on flexural strength enhancement of concrete by means of small steel fibers

he supporting loading rollers, specimen and bearing surfaces have been cleaned. The specimens have been weighed and marked then placed in the machine in right angle to the rollers. In beam B1 and B2 the strain gauges have been installed on one third of end at each side of beam. The maximum applied force, stroke and time to failure of beams have been recorded by using strain gauges. The load has been applied to beam steadily without shock. The rate of loading has been maintained in constant level until failure of beam. The types of failure mode and crack have been recorded.
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Lat. Am. j. solids struct.  vol.12 número8

Lat. Am. j. solids struct. vol.12 número8

Consequently, for measurement of bending deformation in Case.2, the strain-gauges can be ar- ranged at the end of each beam, and the beam’s side where neutral axis exists can be unoccupied. For measurement of tensile-compressive deformation in Case.1, discriminating measurement is taken into account so that the strain-gauges are arranged on neutral axis of each beam. Also, a finite ele- ment verification of the pure theoretical analysis was provided by us (Lin et al., 2014). However, the significance is that this detailed illustration not only gives the static strain and deformation analysis of the elastic body, but it will also be significant and applicable for the inertia load analysis of the transducer.
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Numerical and Experimental Analysis in the Manipulation of the Mechanical Properties for Enhancing the Mechanical Resistance of a Material

Numerical and Experimental Analysis in the Manipulation of the Mechanical Properties for Enhancing the Mechanical Resistance of a Material

crack in a residual stress field and provides the means to measure crack closure stresses. This technique can be fairly easily applied with commonly available equipment such as strain gauges and electric discharge or conventional machining. This offers increased spatial resolution of residual stresses and sensitivity to low stresses. The CCM can be applied to many distinctive materials including different metals, polymers and composites. Different geometrical tested configurations include surface and through thickness measurements, axial stresses in plates (beams and strips), axi-symmetric stress in cylindrical components, pre-cracked specimens, central holes, and others [8-11].
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Alternative Method for Determining the Elastic Modulus of Concrete

Alternative Method for Determining the Elastic Modulus of Concrete

The results showed that the DIC technique provides values equivalent to the values obtained using traditional strain gauges as well as significant advantages. The first major advantage is that the DIC technique can be used without surface preparation or for the preparation of only a small region. Currently, no dependence exists for the randomness of the medium for this technique. The second major advantage is that the dynamics and flexibility of the DIC technique can be applied for studies in which the electrical strain gauge or mechanical strain gauge are not possible, including samples of various sizes. The third advantage includes the accuracy of the system, which can be improved in accordance with the situation by changing both the focal length and the focus area to achieve greater precision. Finally, the proposed system offers low-cost, easy use and sustainability because the hardware can be reused indefinitely.
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J. Aerosp. Technol. Manag.  vol.4 número4

J. Aerosp. Technol. Manag. vol.4 número4

samples in dual cantilever clamp at 35 ºC for a ten-minute period with the stress applied varying from 0.1 to 3 MPa and measuring the corresponding creep compliances. A plot of creep compliance versus time for high burning rate composite propellant under creep subjected to different stress levels at 35 ºC is shown in Fig. 11, which infers that as the stress level increases the creep compliance versus time curve shifts downwards, that is, the creep compliance decreases ZLWKLQFUHDVHLQVWUHVV6LQFHWKHFUHHSFRPSOLDQFHLVWKH reciprocal of modulus and this is the ratio of stress by strain, therefore, as the stress level increases the modulus increases accordingly, leading to decrease in the compliance. Fig. 11 also reveals that the difference between creep compliance for stress values around 0.1 and 0.5 MPa is more than the difference between the creep compliance for stress values around 2 and 3 MPa. This may be accounted to the fact that at higher stress values the material is strained beyond
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Evaluation of thermal effects and strain-rate sensitivity in frozen soil

Evaluation of thermal effects and strain-rate sensitivity in frozen soil

A split Hopkinson pressure bar apparatus was used in the frozen soil experiments under impact load- ing. In order to match the specimen (30 mm in diameter and 18 mm in length), the incident bar adopted used a variable cross-section bar with a right cone; the bar was 30 mm in diameter and 525 mm in length. The trans- mitted bar was 400 mm long. Strain gages were mount- ed on both the incident bar and transmitted bars. Based on one-dimensional stress wave theory and assumptions of homogeneity, the stress, strain, and strain rate were calculated by the classical two-wave method.
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Strain bidimensional na cardiopatia de Takotsubo.

Strain bidimensional na cardiopatia de Takotsubo.

This report presents the late follow-up of a case of Takotsubo cardiomyopathy with good clinical outcome and improved left ventricular global systolic function. However, there was persistence of significant regional longitudinal systolic dysfunction evaluated using a new echocardiographic technique (speckle tracking), with corresponding measures of strain (S) and strain rate (SR). We emphasize the importance of this new method to monitoring this cardiomyopathy, since it identifies patients with persistent systolic dysfunction who will possibly benefit from maintenance of clinical therapy.
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Agrobacterium strain and growth

Agrobacterium strain and growth

used: two plants were inoculated with each of the PVY strains and the third was kept virus-free and grown together as a negative control. The inoculation was conducted two to three weeks after emergence and consisted rubbing the potato leaves previously dusted with Carborundum with a PVY infected macerate of Nicotiana tabacum leaves at 1:10 dilution in 0.01 M phosphate buffer plus 1% sodium sulfite. The plants were inoculated twice, with the same PVY strain, over 48 hours. Non- transformed virus-free potato plants, cultivar Achat, were also inoculated and used as a positive control. The clones that did not show symptoms were selected. New tubers of these plants were planted and the plants were inoculated in the same way as described above, using eight plants per clone and two viral dilutions in the inoculation suspension: 1:20 and 1:40. ELISA was performed 15 and 21 days after the first inoculation, using polyclonal antibodies against PVY in a double antibody sandwich format (Clark & Adams, 1977). All bioassays were performed under controlled conditions to avoid aphids and to prevent any risk of environmental spread of transgenic material.
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MATERIAL AND METHODS Strain

MATERIAL AND METHODS Strain

Observations regarding the phytotoxic damage rating on treatment with different days old metabolized broth and 21 days old CFCF of different concentrations on te[r]

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Avaliação da função cardíaca de crianças e adolescentes obesos por meio das técnicas strain e strain rate baseadas no doppler e speckle tracking bidimensional

Avaliação da função cardíaca de crianças e adolescentes obesos por meio das técnicas strain e strain rate baseadas no doppler e speckle tracking bidimensional

Em outro estudo no mesmo ano, utilizando a técnica de strain e SR para analisar o efeito da perda de peso a partir de mudanças de hábitos (dieta e atividade física), apurou-se melhora da função diastólica dos pacientes ,40 . Em outros estudos foi confirmada, também, importante relação entre obesidade, resistência à insulina e disfunções sistólica e diastólica 41,42 . Mais recentemente, em 2011, evidenciou-se que pacientes hipertensos obesos, quando comparados a hipertensos não obesos, demostravam piora na função cardíaca 43 . Na avaliação de pacientes com obesidade mórbida, ou seja, IMC acima de 40 kg/m 2 , constatou- se disfunção sistólica e diastólica biventricular 44 . Na avaliação da função do ventrículo direito (VD) em pacientes com síndrome metabólica, registrou-se diminuída performance ventricular. Na mesma investigação, observou-se relação E/e’ estatisticamente superior em relação ao grupo-controle, caracterizando disfunção diastólica 45 .
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Identification of the strain

Identification of the strain

Abstract – A fermentative acetic acid producing strain, named CSJ-3, was isolated from sludge and identified as Pseudomonas sp. on the basis of 16S rRNA gene analysis. The effects of cultivation conditions on the production of acetic acid by Pseudomonas sp. CSJ-3 were investigated in batch fermentation, and the maximum yield of acetic acid reached up to 0.49 % during 30 h cultivation under the optimum growth condition, including fermentation temperature of 37.0 °C, fermentation pH of 4.50, ethanol concentration of 8 %, carbon source (glucose) amount of 10 g/L, and rotation speed of 120 r/min. When ultraviolet (UV) irradiation was used for the mutation in culture medium to improve the yield of acetic acid, the results showed that the yield of acetic acid reached up to 0.59 %. UV and FTIR confirmed that acetic acid was the major fermented product.
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Evaporation from weighing precipitation gauges: impacts on automated gauge measurements and quality assurance methods

Evaporation from weighing precipitation gauges: impacts on automated gauge measurements and quality assurance methods

However, recent research comparing USCRN with COOP stations indicate gauge evaporation can bias observations even when taken frequently at a sub-hourly rate (Leeper et al., 2015a). The USCRN monitors precipitation at a 5 min frequency from a well-shielded automated funnel-less gauge whereas COOP stations operate a manual funnel-capped gauge that is checked daily. Despite COOP stations monitor- ing precipitation from an unshielded gauge, USCRN obser- vations of precipitation (daily aggregated sum of sub-hourly data) were slightly less than COOP by 1.5 % (Leeper et al., 2015a). Network differences were not as large for northern- located station pairs that had a greater percentage of frozen hydrometeors, which are more sensitive to surface wind and where gauge shielding has a more dominant impact on catch efficiency (Leeper et al., 2015a). Overall, these results are contrary to other studies that found unshielded gauges tended to report 4 to 11 % less precipitation for liquid hydrometeors (Golubev et al., 1992; and Duchon and Essenberg, 2001), al- though neither included the Geonor gauge used at USCRN stations. A portion of the dry bias between USCRN and COOP, among others (i.e., wetting factor, observer error), was thought to be attributed to computational methods within the quality assurance (QA) system that may be sensitive to
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MATERIALS AND METHODS Bacterial strain

MATERIALS AND METHODS Bacterial strain

To localize the intracellular site of accumulated Cd, cells of KUCd1 were observed under TEM. The transmission electron micrograph (Fig. 4) showed electron dense grains in the cytosol and towards the cell envelope. For further analysis of the electron dense bodies, EDXS study was performed. The data showed the peak for Cd in the treated cells (Fig. 5). The strain could produce sulfide when grown on SIM agar tube as indicated by black coloration along the line of stab inoculation. This production of sulfide might confer Cd resistance in this strain for its survival under Cd stress and it detoxifies Cd by converting it into insoluble CdS as reported earlier (25, 30, 31). So biochemical and EDXS data predict that the test strain might convert cadmium into CdS under Cd stress condition. The powdered X ray diffraction data of the Cd loaded cells revealed the chemical nature of the accumulated Cd within the cell (Fig. 6). The broadened nature of the peaks in the diffractogram indicates the existence of amorphous phase(s) in the sample. However, from the intensity distribution pattern of the diffractogram, existence of a peak at 2θ = 31.54 can readily be understood. Based on the d value, the peak at 2θ = 31.54 might be assigned as CdS. In the Cd untreated set there was no such conspicuous peak for CdS. This observation supports the earlier findings in the present study that the strain tolerated such high level of Cd by depositing insoluble CdS. However, the processes of physical adsorption or complexation of Cd by the dead cell mass could not be eliminated in this strain because of higher amount of Cd removal during stationary phase and warrant further investigation.
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URBAN RAIN GAUGE SITING SELECTION BASED ON GIS-MULTICRITERIA ANALYSIS

URBAN RAIN GAUGE SITING SELECTION BASED ON GIS-MULTICRITERIA ANALYSIS

Figure 4. Workflow of rain gauge site selection On the basis of the aforementioned rules and guidelines, the garbage houses and public toilets Figure 5(a) of Xicheng District in China are chosen as the initial positions for rain gauges, other input parameters includes roads (Figure 5(b)), residential areas (Figure 5(c)), substations, high-voltage wires (Figure 5(d)), and precipitation. Under the support of GIS platform, the input data will be addressed via spatial analyses, such as kernel density (Figure 6(a)), buffer analysis (Figure 6(b),(c)), Inversed Distance Weighted as well, and the output results (density, distance, and rainfall) can be classified into five ranks respectively.
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