State special primary acceleration measurement standard for gravimetry GET 190-2019

2020 ◽  
pp. 3-8
Author(s):  
L.F. Vitushkin ◽  
F.F. Karpeshin ◽  
E.P. Krivtsov ◽  
P.P. Krolitsky ◽  
V.V. Nalivaev ◽  
...  
Keyword(s):  
High Precision ◽  
Free Fall ◽  
Measurement Range ◽  
Measurement Standard ◽  
Acceleration Measurement ◽  
Measurement Systems ◽  
Free Fall Acceleration ◽  
Investigation Methods ◽  
Measurement Results ◽  
Upper Level

The State special primary acceleration measurement standard for gravimetry (GET 190-2019), its composition, principle of operation and basic metrological characteristics are presented. This standard is on the upper level of reference for free-fall acceleration measurements. Its accuracy and reliability were improved as a result of optimisation of the adjustment procedures for measurement systems and its integration within the upgraded systems, units and modern hardware components. A special attention was given to adjusting the corrections applied to measurement results with respect to procedural, physical and technical limitations. The used investigation methods made it possibled to confirm the measurement range of GET 190-2019 and to determine the contributions of main sources of errors and the total value of these errors. The measurement characteristics and GET 90-2019 were confirmed by the results obtained from measurements of the absolute value of the free fall acceleration at the gravimetrical site “Lomonosov-1” and by their collation with the data of different dates obtained from measurements by high-precision foreign and domestic gravimeters. Topicality of such measurements ensues from the requirements to handle the applied problems that need data on parameters of the Earth gravitational field, to be adequately faced. Geophysics and navigation are the main fields of application for high-precision measurements in this field.

A Compound Recoil-Compensated Chamber Design for Free-Fall Absolute Gravimeters

2020 ◽  
Author(s):  
Yi Wen ◽  
Kang Wu ◽  
Meiying Guo ◽  
Lijun Wang
Keyword(s):  
High Precision ◽  
Free Fall ◽  
Test Mass ◽  
Precision Measurements ◽  
Gravity Measurement ◽  
Absolute Gravity ◽  
Systematic Bias ◽  
Chamber Design ◽  
Measurement Results ◽  
Gravity Measurements

Abstract The ballistic free-fall absolute gravimeters are most commonly-used instruments for high-precision absolute gravity measurements in many fields, such as scientific research, resource survey, geophysics and so on. The instrumental recoil vibrations generated by the release of the test mass can cause troublesome systematic bias, because these vibrations are highly reproducible from drop to drop with coherent phase. A compound counterbalanced design of chamber using both belt-driven mechanism and cam-driven structure is proposed in this paper. This structure is designed to achieve excellent recoil compensation as well as long freefall length for high precision measurements. Simulation results show that the recoil vibration amplitude of the compound recoil-compensated structure during the drop is about 1/4 of that with only belt-driven counterbalanced structure. This confirms the feasibility and superiority of the new design. And it is believed that the absolute gravimeter based on this newly proposed chamber design is expected to obtain more precise gravity measurement results in the future.

Investigation of the Accuracy of Reference Instruments for Measuring Vertical Angles by Reference Method of Their Calibration

2020 ◽  
pp. 3-14
Author(s):  
O. M. Samoylenko ◽  
O. V. Adamenko ◽  
B. P. Kukareka
Keyword(s):  
Horizontal Plane ◽  
Opposite Sign ◽  
Reference Method ◽  
Angle Measurement ◽  
Measurement Standard ◽  
Vertical Angle ◽  
Measurement Standards ◽  
Measurement Results ◽  
Electronic Measurement ◽  
Systematic Biases

Reference method for simultaneous calibration of the three and more measurement standards for vertical angle measurement is developed. This method can to use for obtaining the systematic biases of the vertical angles measurements for each of the measuring standards relative of the horizontal plain was averaged from measurement results in time their calibration or comparison. For realization of the reference method was developed the autocollimationel electronic measurement standard for the automatization measurement of the vertical angles SeaLineZero_Standard™ (SLZ_S™). Summary standard deviation (k=1) of the vertical angle measurement relative the horizontal plane, from the results of their calibration by reference method, is not more 0,07ʺ…0,15ʺ. This result was obtained without the use the systematic biases, for each measurement standards, as measurements corrections (with opposite sign). The measuring standards, that were developed and researched, are necessary for obtaining the systematic biases of the vertical angle measurement for total stations and theodolites, that have the normed standard error 0,5ʺ and 1ʺ, when these instruments are calibrating.

Comparison of measurement systems for free fall tests and calculations of the coefficient of restitution

2018 ◽  
Vol 29 (10) ◽  
pp. 105403
Author(s):  
Michael Trüe ◽  
Ronny Böttcher ◽  
Oliver Faßhauer ◽  
Sergej Aman ◽  
Berend van Wachem ◽  
...  
Keyword(s):  
Free Fall ◽  
Coefficient Of Restitution ◽  
Measurement Systems

scholarly journals High precision machining of a displacement sensor for helicoidal motions

2021 ◽  
Author(s):  
Zeina ELRAWASHDEH ◽  
Philippe REVEL ◽  
Christine PRELLE ◽  
Frédéric LAMARQUE
Keyword(s):  
High Precision ◽  
Fiber Optic ◽  
Geometric Model ◽  
Translational Motion ◽  
Surface Characteristics ◽  
Measurement Range ◽  
Linear Displacement ◽  
Displacement Sensor ◽  
Fiber Optic Probes

Abstract This research study presents the design and the high precision manufacture procedure of a fiber-optic displacement sensor. It is composed of two fiber-optic probes associated with a structure of a cones’ grating. The sensor is characterized by its ability to measure the linear displacement for an axis performing a helicoidal motion. This motion has been demonstrated on a high precision lathe; where the spindle provided the rotational motion, associated to a translational motion on the linear stage. This allowed to obtain the two simultaneous motions. The displacement of the translational stage is measured by the sensor in real time.Firstly, a highly precise geometric model of the reflector part for the sensor was developed. This model provided a specific geometry for the cones-assembled grating, which has been precisely manufactured. The geometric parameters and the surface characteristics of each step in the fabricated grating were both identified in situ on the lathe. The agreement between simulation and experimental results is excellent. The performances of the fiber-optic displacement sensor were identified in-situ on the lathe. The analysis of the voltage output signals from the two fiber-optic probes is used to measure the grating displacement. The unbalanced rotation due to non-centered axes was also characterized. The sensor provided a micrometric resolution, on a measurement range of more than one centimeter.

Design of PT100 high-precision temperature measurement systems based on third-order model

2020 ◽  
Vol 563 (1) ◽  
pp. 118-127
Author(s):  
Wei Wang ◽  
Mingxia Yang ◽  
Liyuan Yu ◽  
Dali Liu
Keyword(s):  
Temperature Measurement ◽  
High Precision ◽  
Order Model ◽  
Third Order ◽  
Measurement Systems ◽  
Precision Temperature

scholarly journals High Precision, Small Size and Flexible FBG Strain Sensor for Slope Model Monitoring

Sensors ◽  
2019 ◽  
Vol 19 (12) ◽  
pp. 2716 ◽  
Author(s):  
Hongbin Xu ◽  
Xinyu Zheng ◽  
Weigang Zhao ◽  
Xu Sun ◽  
Feng Li ◽  
...  
Keyword(s):  
High Precision ◽  
Strain Sensor ◽  
Horizontal Displacement ◽  
Steel Plates ◽  
Flexible Structure ◽  
Test Results ◽  
Bending Angle ◽  
Subsurface Deformation ◽  
Measurement Results ◽  
Sensor Monitoring

In this paper, a soft fiber Bragg grating (FBG) strain sensor was constructed of a rubber strip, FBGs and steel plates, which exhibits the advantages of high precision and a small size. A series of FBGs was uniformly pasted on a flexible rubber strip which can monitor the slope deformation by measuring the bending deformation of the rubber strip. Most notably, this sensor can be used to monitor horizontal displacement in the subsurface of the slope model. The relationships among the bending angle of the rubber strip, the strain of the rubber strip, and the subsurface deformation of the slope model were established. In addition, the subsurface deformation of the slope model can be obtained by the FBG strain sensor monitoring. Since a rigid-flexible structure was formed by uniformly pasting a series of steel plates on the other side of the rubber strip, the sensitivity of the FBG strain sensor was improved to be 1.5425 nm/°. The measurement results verify that the FBG strain sensor shows good performance, and the model test results demonstrate that the FBG strain sensor can be used for monitoring the subsurface deformation of the slope model.

scholarly journals Quantum Vacuum Energy and the Emergence of Gravity An Essay

2018 ◽  
Vol 10 (2) ◽  
pp. 1
Author(s):  
Philip J. Tattersall
Keyword(s):  
Gravitational Field ◽  
Vacuum Energy ◽  
Free Fall ◽  
Energy Coupling ◽  
Quantum Vacuum ◽  
Free Fall Acceleration ◽  
Energy Gradient

Building on the work of others a novel idea is put forward regarding the possible mechanism of gravity as involving energy coupling down the energy gradient of a massive body. Free fall (acceleration) in a gravitational field is explained as arising from an interaction of the modified quantum vacuum energy in the vicinity of matter.

scholarly journals High-Precision Acceleration Measurement System Based on Tunnel Magneto-Resistance Effect

Sensors ◽  
2020 ◽  
Vol 20 (4) ◽  
pp. 1117 ◽  
Author(s):  
Lu Gao ◽  
Fang Chen ◽  
Yingfei Yao ◽  
Dacheng Xu
Keyword(s):  
Magnetic Field ◽  
High Precision ◽  
Measurement System ◽  
Frequency Modulation ◽  
High Frequency ◽  
Low Noise ◽  
Acceleration Measurement ◽  
Field Source ◽  
Modulation Technique ◽  
Magneto Resistance

A high-precision acceleration measurement system based on an ultra-sensitive tunnel magneto-resistance (TMR) sensor is presented in this paper. A “force–magnetic–electric” coupling structure that converts an input acceleration into a change in magnetic field around the TMR sensor is designed. In such a structure, a micro-cantilever is integrated with a magnetic field source on its tip. Under an acceleration, the mechanical displacement of the cantilever causes a change in the spatial magnetic field sensed by the TMR sensor. The TMR sensor is constructed with a Wheatstone bridge structure to achieve an enhanced sensitivity. Meanwhile, a low-noise differential circuit is developed for the proposed system to further improve the precision of the measured acceleration. The experimental results show that the micro-system achieves a measurement resolution of 19 μg/√Hz at 1 Hz, a scale factor of 191 mV/g within a range of ± 2 g, and a bias instability of 38 μg (Allan variance). The noise sources of the proposed system are thoroughly investigated, which shows that low-frequency 1/f noise is the dominant noise source. We propose to use a high-frequency modulation technique to suppress the 1/f noise effectively. Measurement results show that the 1/f noise is suppressed about 8.6-fold at 1 Hz and the proposed system resolution can be improved to 2.2 μg/√Hz theoretically with this high-frequency modulation technique.

Extended multivariate approach for uncertainty reduction in the assessment of undrained shear strength in clays

2014 ◽  
Vol 51 (3) ◽  
pp. 231-245 ◽  
Author(s):  
Rasmus Müller ◽  
Stefan Larsson ◽  
Johan Spross
Keyword(s):  
Shear Strength ◽  
Site Investigation ◽  
Undrained Shear Strength ◽  
Multivariate Approach ◽  
Total Uncertainty ◽  
Investigation Methods ◽  
Measurement Results ◽  
Strength Formula ◽  
A Site ◽  
Undrained Shear

Important features of the multivariate approach are discussed, and an extension to this approach is proposed whereby the total uncertainty in site investigation methods due to spatial averaging is assessed prior to its adoption. Results from a site investigation of spatially averaged values of undrained shear strength ([Formula: see text]) and the corresponding coefficient of variation ([Formula: see text]) in Veda sulphide clay were used as a practical illustration of the extended multivariate approach and provide a basis for discussion. The inherent variability and scales of fluctuation for different methods are presented. The study shows the usefulness of the extended multivariate approach for the evaluation of representative values of [Formula: see text] and [Formula: see text] based on results from different methods. It is also a way of implicitly reducing the transformation errors that arise when a property is derived from measurement results. Nevertheless, considerable care must be taken as a much lower COV for one method will have a significant impact on the results.

Sign in / Sign up

Export Citation Format

Share Document