Acceleration measurement model and uncertainty evaluation of 10-6 order precision centrifuge

This paper introduces a prototype of the inertial sensor based on electromagnetic suspension. By analyzing and simulating the change of the magnetic field, the dynamic equation of proof mass has been deduced. The device has the characteristics of a high-frequency accelerometer and a vibration frequency sensor, and the horizontal and vertical frequency ranges of the magnetic suspension acceleration measurement system are 50–500 Hz and 35–650 Hz, and the acceleration measurement ranges are ±3.3 m/s 2 and ±10 m/s 2 , respectively. Compared with the MPU6050 accelerometer, this measurement method has higher sensitivity and retains more vibration acceleration information of the measured object. This paper provides a new idea for the design of the acceleration sensor.

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The calibration and uncertainty evaluation by elementary measurement models

Measurements infrastructure ◽

10.33955/v1(2021)-005 ◽

2021 ◽

Vol 1 ◽

pp. 1-10

Author(s):

Oleksandr Samoilenko

Keyword(s):

Measurement Model ◽

Uncertainty Evaluation ◽

Measuring Instruments ◽

Measuring Instrument ◽

Measurement Standard ◽

Measurement Result ◽

Average Value ◽

Measurement Models ◽

Material Measure ◽

Object Material

Nature has often made necessary things simple (elementary) and complicated ones unnecessary. This can be applied to measurement models of the large amount of working measurement standards and working measuring instruments. Nevertheless, if measurement model is elementary, it does not mean that it is primitive. It should be formulated according to the sufficiency, mathematical completeness and correctness principles. The attempt to formulate models according to the mentioned principles is introduced. Models are called elementary, as measurement result is function of one or two homogeneous measured quantities. Thus, measurement result is a single reading of the measurement standard or measuring instrument or average value of several readings, or bias as the disparity between readings of the calibrated measuring instrument and measurement standard. Notwithstanding the elementary measurement models simplicity, many variants of solutions are obtained in the process of the measurement result uncertainty evaluation by these models. Publication demonstrates how to choose the best uncertainty evaluation from many variants of solutions depending on whether single readings or average of several readings is included to measurement model. The best choice of the measurement model depends on resolution of the indicating measuring instrument. Moreover, the best choice depends on the measurement standard used for calibration, which is material measure or measuring instrument and depends on the calibration object: material measure or measuring instrument.

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Uncertainty evaluation of measurement of orientation repeatability for industrial robots

Industrial Robot the international journal of robotics research and application ◽

10.1108/ir-07-2019-0145 ◽

2020 ◽

Vol 47 (2) ◽

pp. 207-217

Author(s):

Yang Chuangui ◽

Mi Liang ◽

Liu Xingbao ◽

Xia Yangqiu ◽

Qiang Teng ◽

...

Keyword(s):

Monte Carlo ◽

Linear Problem ◽

Industrial Robot ◽

Measurement Model ◽

Industrial Robots ◽

Uncertainty Evaluation ◽

Laser Tracker ◽

Uncertainty Of Measurement ◽

Content Type ◽

Non Linear

Purpose This paper aims to propose a reasonable method to evaluate uncertainty of measurement of industrial robots’ orientation repeatability and solve the non-linear problem existing in its evaluation procedure. Design/methodology/approach Firstly, a measurement model of orientation repeatability, based on laser tracker, is established. Secondly, some factors, influencing the measurement result of orientation repeatability, are identified, and their probability distribution functions are modelled. Thirdly, based on Monte Carlo method, an uncertainty evaluation model and algorithm of measurement of industrial robot’s orientation repeatability are built. Finally, an industrial robot is taken as the research object to validate the rationality of proposed method. Findings Results show that the measurement model of orientation repeatability of industrial robot is non-linear, and the proposed method can reasonably and objectively estimate uncertainty of measurement of industrial robots’ orientation repeatability. Originality/value This paper, based on Monte Carlo method and experimental work, proposes an uncertainty evaluation method of measurement of industrial robots’ orientation repeatability which can solve the non-linear problem and provide a reasonable and objective evaluation. And the stochastic ellipsoid approach is firstly taken to model the repeatability of laser tracker. Additionally, this research is beneficial to decide whether the orientation repeatability of the industrial robot meets its requirements.

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Example of Monte Carlo Method Uncertainty Evaluation for Above-Water Ocean Colour Radiometry

Remote Sensing ◽

10.3390/rs12050780 ◽

2020 ◽

Vol 12 (5) ◽

pp. 780 ◽

Cited By ~ 4

Author(s):

Agnieszka Białek ◽

Sarah Douglas ◽

Joel Kuusk ◽

Ilmar Ansko ◽

Viktor Vabson ◽

...

Keyword(s):

Monte Carlo ◽

Monte Carlo Method ◽

Measurement Uncertainty ◽

Measurement Model ◽

Uncertainty Evaluation ◽

Ocean Colour ◽

Monte Carlo Approach ◽

Radiometric Measurements ◽

Downwelling Irradiance

We describe a method to evaluate an uncertainly budget for the in situ Ocean Colour Radiometric measurements. A Monte Carlo approach is chosen to propagate the measurement uncertainty inputs through the measurements model. The measurement model is designed to address instrument characteristics and uncertainty associated with them. We present the results for a particular example when the radiometers were fully characterised and then use the same data to show a case when such characterisation is missing. This, depending on the measurement and the wavelength, can increase the uncertainty value significantly; for example, the downwelling irradiance at 442.5 nm with fully characterised instruments can reach uncertainty values of 1%, but for the instruments without such characterisation, that value could increase to almost 7%. The uncertainty values presented in this paper are not final, as some of the environmental contributors were not fully evaluated. The main conclusion of this work are the significance of thoughtful instrument characterisation and correction for the most significant uncertainty contributions in order to achieve a lower measurements uncertainty value.

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A BAYESIAN ANALYSIS FOR THE UNCERTAINTY EVALUATION OF A MULTIVARIATE NON LINEAR MEASUREMENT MODEL

Advanced Mathematical and Computational Tools in Metrology VII ◽

10.1142/9789812774187_0016 ◽

2006 ◽

Author(s):

GABRIELLA PELLEGRINI ◽

GAETANO IUCULANO ◽

ANDREA ZANOBINI

Keyword(s):

Bayesian Analysis ◽

Measurement Model ◽

Linear Measurement ◽

Uncertainty Evaluation ◽

Non Linear

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Instrumental and Ideological Union Commitment: Longitudinal Assessment of Construct Validity

European Journal of Psychological Assessment ◽

10.1027//1015-5759.17.2.98 ◽

2001 ◽

Vol 17 (2) ◽

pp. 98-111 ◽

Cited By ~ 1

Author(s):

Anders Sjöberg ◽

Magnus Sverke

Keyword(s):

Construct Validity ◽

Temporal Stability ◽

Strong Support ◽

Internal Consistency Reliability ◽

Measurement Model ◽

Two Dimensions ◽

Model Parameters ◽

Longitudinal Assessment ◽

Union Commitment ◽

Union Participation

Summary: Previous research has identified instrumentality and ideology as important aspects of member attachment to labor unions. The present study evaluated the construct validity of a scale designed to reflect the two dimensions of instrumental and ideological union commitment using a sample of 1170 Swedish blue-collar union members. Longitudinal data were used to test seven propositions referring to the dimensionality, internal consistency reliability, and temporal stability of the scale as well as postulated group differences in union participation to which the scale should be sensitive. Support for the hypothesized factor structure of the scale and for adequate reliabilities of the dimensions was obtained and was also replicated 18 months later. Tests for equality of measurement model parameters and test-retest correlations indicated support for the temporal stability of the scale. In addition, the results were consistent with most of the predicted differences between groups characterized by different patterns of change/stability in union participation status. The study provides strong support for the construct validity of the scale and indicates that it can be used in future theory testing on instrumental and ideological union commitment.

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