Issues

Journal & Issues

Volume 22 (2022): Issue 5 (October 2022)

Volume 22 (2022): Issue 4 (August 2022)

Volume 22 (2022): Issue 3 (June 2022)

Volume 22 (2022): Issue 2 (April 2022)

Volume 22 (2022): Issue 1 (February 2022)

Volume 21 (2021): Issue 6 (December 2021)

Volume 21 (2021): Issue 5 (October 2021)

Volume 21 (2021): Issue 4 (August 2021)

Volume 21 (2021): Issue 3 (June 2021)

Volume 21 (2021): Issue 2 (April 2021)

Volume 21 (2021): Issue 1 (February 2021)

Volume 20 (2020): Issue 5 (October 2020)

Volume 20 (2020): Issue 4 (August 2020)

Volume 20 (2020): Issue 3 (June 2020)

Volume 20 (2020): Issue 2 (April 2020)

Volume 20 (2020): Issue 1 (February 2020)

Volume 19 (2019): Issue 6 (December 2019)

Volume 19 (2019): Issue 5 (October 2019)

Volume 19 (2019): Issue 4 (August 2019)

Volume 19 (2019): Issue 3 (June 2019)

Volume 19 (2019): Issue 2 (April 2019)

Volume 19 (2019): Issue 1 (February 2019)

Volume 18 (2018): Issue 6 (October 2018)

Volume 18 (2018): Issue 5 (October 2018)

Volume 18 (2018): Issue 4 (August 2018)

Volume 18 (2018): Issue 3 (June 2018)

Volume 18 (2018): Issue 2 (April 2018)

Volume 18 (2018): Issue 1 (February 2018)

Volume 17 (2017): Issue 6 (December 2017)

Volume 17 (2017): Issue 5 (October 2017)

Volume 17 (2017): Issue 3 (June 2017)

Volume 17 (2017): Issue 2 (April 2017)

Volume 17 (2017): Issue 1 (February 2017)

Volume 16 (2016): Issue 6 (December 2016)

Volume 16 (2016): Issue 5 (October 2016)

Volume 16 (2016): Issue 4 (August 2016)

Volume 16 (2016): Issue 3 (June 2016)

Volume 16 (2016): Issue 2 (April 2016)

Volume 16 (2016): Issue 1 (February 2016)

Volume 15 (2015): Issue 6 (December 2015)

Volume 15 (2015): Issue 5 (October 2015)

Volume 15 (2015): Issue 4 (August 2015)

Volume 15 (2015): Issue 3 (June 2015)

Volume 15 (2015): Issue 2 (April 2015)

Volume 15 (2015): Issue 1 (February 2015)

Volume 14 (2014): Issue 6 (December 2014)

Volume 14 (2014): Issue 5 (October 2014)

Volume 14 (2014): Issue 4 (August 2014)

Volume 14 (2014): Issue 3 (June 2014)

Volume 14 (2014): Issue 2 (April 2014)

Volume 14 (2014): Issue 1 (February 2014)

Volume 13 (2013): Issue 6 (December 2013)

Volume 13 (2013): Issue 5 (October 2013)

Volume 13 (2013): Issue 4 (August 2013)

Volume 13 (2013): Issue 3 (June 2013)

Volume 13 (2013): Issue 2 (April 2013)

Volume 13 (2013): Issue 1 (February 2013)

Volume 12 (2012): Issue 6 (December 2012)

Volume 12 (2012): Issue 5 (October 2012)

Volume 12 (2012): Issue 4 (August 2012)

Volume 12 (2012): Issue 3 (June 2012)

Volume 12 (2012): Issue 2 (April 2012)

Volume 12 (2012): Issue 1 (February 2012)

Volume 11 (2011): Issue 6 (December 2011)

Volume 11 (2011): Issue 5 (October 2011)

Volume 11 (2011): Issue 4 (August 2011)

Volume 11 (2011): Issue 3 (June 2011)

Volume 11 (2011): Issue 2 (April 2011)

Volume 11 (2011): Issue 1 (February 2011)

Volume 10 (2010): Issue 6 (December 2010)

Volume 10 (2010): Issue 5 (October 2010)

Volume 10 (2010): Issue 4 (August 2010)

Volume 10 (2010): Issue 3 (June 2010)

Volume 10 (2010): Issue 2 (April 2010)

Volume 10 (2010): Issue 1 (February 2010)

Volume 9 (2009): Issue 6 (December 2009)

Volume 9 (2009): Issue 5 (October 2009)

Volume 9 (2009): Issue 4 (August 2009)

Volume 9 (2009): Issue 3 (June 2009)

Volume 9 (2009): Issue 2 (April 2009)

Volume 9 (2009): Issue 1 (February 2009)

Volume 8 (2008): Issue 6 (December 2008)

Volume 8 (2008): Issue 5 (October 2008)

Volume 8 (2008): Issue 4 (August 2008)

Volume 8 (2008): Issue 3 (June 2008)

Volume 8 (2008): Issue 2 (April 2008)

Volume 8 (2008): Issue 1 (February 2008)

Journal Details
Format
Journal
eISSN
1335-8871
First Published
07 Mar 2008
Publication timeframe
6 times per year
Languages
English

Search

Volume 20 (2020): Issue 1 (February 2020)

Journal Details
Format
Journal
eISSN
1335-8871
First Published
07 Mar 2008
Publication timeframe
6 times per year
Languages
English

Search

6 Articles
access type Open Access

Measurement Science is the Science of Sciences - There is no Science without Measurement

Published Online: 24 Feb 2020
Page range: 1 - 5

Abstract

Abstract

Omnia in mensura et numero et pondere disposuisti is a famous Latin phrase from Solomon’s Book of Wisdom, dated to the mid first century BC, meaning that all things were ordered in measure, number, and weight. Naturally, the wisdom is appearing in its relation to man. The Wisdom of Solomon is understood as the perfection of knowledge of the righteous as a gift from God showing itself in action. Consequently, a natural and obvious conjecture is that measurement science is the science of sciences. In fact, it is a basis of all experimental and theoretical research activities. Each measuring process assumes an object of measurement. Some science disciplines, such as quantum physics, are still incomprehensible despite complex mathematical interpretations. No phenomenon is a real phenomenon unless it is observable in space and time, that is, unless it is a subject to measurement. The science of measurement is an indispensable ingredient in all scientific fields. Mathematical foundations and interpretation of the measurement science were accepted and further developed in most of the scientific fields, including physics, cosmology, geology, environment, quantum mechanics, statistics, and metrology. In this year, 2020, Measurement Science Review celebrates its 20th anniversary and we are using this special opportunity to highlight the importance of measurement science and to express our faith that the journal will continue to be an excellent place for exchanging bright ideas in the field of measurement science. As an illustration and motivation for usage and further development of mathematical methods in measurement science, we briefly present the simple least squares method, frequently used for measurement evaluation, and its possible modification. The modified least squares estimation method was applied and experimentally tested for magnetic field homogeneity adjustment.

Keywords

  • Measurement science
  • linguistic interpretation
  • measuring process
  • physical phenomena
  • measurement evaluation
  • magnetic field
access type Open Access

On Robust Estimation of Error Variance in (Highly) Robust Regression

Published Online: 24 Feb 2020
Page range: 6 - 14

Abstract

Abstract

The linear regression model requires robust estimation of parameters, if the measured data are contaminated by outlying measurements (outliers). While a number of robust estimators (i.e. resistant to outliers) have been proposed, this paper is focused on estimating the variance of the random regression errors. We particularly focus on the least weighted squares estimator, for which we review its properties and propose new weighting schemes together with corresponding estimates for the variance of disturbances. An illustrative example revealing the idea of the estimator to down-weight individual measurements is presented. Further, two numerical simulations presented here allow to compare various estimators. They verify the theoretical results for the least weighted squares to be meaningful. MM-estimators turn out to yield the best results in the simulations in terms of both accuracy and precision. The least weighted squares (with suitable weights) remain only slightly behind in terms of the mean square error and are able to outperform the much more popular least trimmed squares estimator, especially for smaller sample sizes.

Keywords

  • High robustness
  • robust regression
  • outliers
  • variance of errors
  • least weighted squares
  • simulation
access type Open Access

Research on Modified Algorithms of Cylindrical External Thread Profile Based on Machine Vision

Published Online: 24 Feb 2020
Page range: 15 - 21

Abstract

Abstract

In the non-contact detection of thread profile boundary correction, it remains challenging to ensure that the thread axis intersects the CCD camera axis perpendicularly. Here, we addressed this issue using modified algorithms. We established the Cartesian coordinate system according to the spatial geometric relationship of the thread. We used the center of the bottom of the thread as the origin, and the image of the extreme position image was replaced by the image of the approximate extreme position. In addition, we analyzed the relationship between the boundary of the theoretical thread image and the theoretical profile. We calculated the coordinate transformation of the point on the theoretical tooth profile and the coordinate function of the point on the boundary of the theoretical image. At the same time, the extreme value of the function was obtained, and the boundary equation of the theoretical thread image was deduced. The difference equation between the two functions was used to correct the boundary point of the actual thread image, and the fitting results were used to detect the key parameters of the external thread of the cylinder. Further experiment proves that the above algorithm effectively improves the detection accuracy of thread quality, and the detection error of main geometric parameters is reduced by more than 50 %.

Keywords

  • Theoretical tooth profile
  • theoretical image boundary
  • actual tooth profile
  • actual image boundary
  • machine vision
  • difference equation
  • screw thread image processing
access type Open Access

Automatic Strain Gauge Balance Design Optimization Approach and Implementation Based on Integration of Software

Published Online: 24 Feb 2020
Page range: 22 - 34

Abstract

Abstract

The traditional wind tunnel strain balance design cycle is a manual iterative process. With the experience and intuition of the designer, one solution that meets the design requirements can be selected among a small number of design solutions. This paper introduces a novel software integration-based automatic balance design optimization system (ABDOS) and its implementation by integrating professional design knowledge and experience, stepwise optimization strategy, CAD-CAE software, self-developed scripts and tools. The proposed two-step optimization strategy includes the analytical design process (ADP) and the finite element method design process (FEDP). The built-in optimization algorithm drives the design variables change and searches for the optimal structure combination meeting the design objectives. The client-server based network architecture enables local lightweight design input, task management, and result output. The high-performance server combines all design resources to perform all the solution calculations. The development of more than 10 balances that have been completed and a case study show that this method and platform significantly reduce the time for design evaluation and design-analysis-redesign cycles, assisting designers to comprehensively evaluate and improve the performance of the balance.

Keywords

  • Strain gauge balance
  • automatic design
  • structural optimization
  • software integration
  • optimization strategy
access type Open Access

Two-Stage Kalman Filter for Fault Tolerant Estimation of Wind Speed and UAV Flight Parameters

Published Online: 24 Feb 2020
Page range: 35 - 42

Abstract

Abstract

In this study, an estimation algorithm based on a two-stage Kalman filter (TSKF) was developed for wind speed and Unmanned Aerial Vehicle (UAV) motion parameters. In the first stage, the wind speed estimation algorithm is used with the help of the Global Positioning System (GPS) and dynamic pressure measurements. Extended Kalman Filter (EKF) is applied to the system. The state vector is composed of the wind speed components and the pitot scale factor. In the second stage, in order to estimate the state parameters of the UAV, GPS, and Inertial Measurement Unit (IMU) measurements are considered in a Linear Kalman filter. The second stage filter uses the first stage EKF estimates of the wind speed values. Between these two stages, a sensor fault detection algorithm is placed. The sensor fault detection algorithm is based on the first stage EKF innovation process. After detecting the fault on the sensor measurements, the state parameters of the UAV are estimated via robust Kalman filter (RKF) against sensor faults. The robust Kalman filter algorithm, which brings the fault tolerance feature to the filter, secures accurate estimation results in case of a faulty measurement without affecting the remaining good estimation characteristics. In simulations, noise increment and bias type of sensor faults are considered.

Keywords

  • Unmanned aerial vehicle
  • Kalman filter
  • fault detection
  • wind speed
  • GPS
  • pitot tube
access type Open Access

Investigation of Phase Pattern Modulation for Digital Fringe Projection Profilometry

Published Online: 24 Feb 2020
Page range: 43 - 49

Abstract

Abstract

The fringe projection profilometry with sinusoidal patterns based on phase-shifting algorithms is commonly distorted by the nonlinear intensity response of commercial projector. In order to solve this issue, sinusoidal width modulation is presented to generate binary sinusoidal patterns for defocusing the projection. However, the residual errors in the phase maps are usually notable for highly accurate three-dimensional shape measurements. In this paper, we propose the fringe patterns of the sinusoidal, square, and triangular periodic waveforms with seven-step phase-shifting algorithm to further improve the accuracy of three-dimensional profile reconstruction. The absolute phase values are calculated by using quality guided path unwrapping. We learn that by properly selecting fringe patterns according to the target shape, the undesired harmonics of the measured surface have negligible effect on the phase values. The experiments are presented to verify the imaging performances of three fringe patterns for different testing targets. The triangular fringe patterns are suitable for the shape measurements of complex targets with curved surfaces. The results provide a great possibility for high-accuracy shape measurement technique with wider measuring depth range.

Keywords

  • Digital imaging
  • fringe projection
  • waveform
6 Articles
access type Open Access

Measurement Science is the Science of Sciences - There is no Science without Measurement

Published Online: 24 Feb 2020
Page range: 1 - 5

Abstract

Abstract

Omnia in mensura et numero et pondere disposuisti is a famous Latin phrase from Solomon’s Book of Wisdom, dated to the mid first century BC, meaning that all things were ordered in measure, number, and weight. Naturally, the wisdom is appearing in its relation to man. The Wisdom of Solomon is understood as the perfection of knowledge of the righteous as a gift from God showing itself in action. Consequently, a natural and obvious conjecture is that measurement science is the science of sciences. In fact, it is a basis of all experimental and theoretical research activities. Each measuring process assumes an object of measurement. Some science disciplines, such as quantum physics, are still incomprehensible despite complex mathematical interpretations. No phenomenon is a real phenomenon unless it is observable in space and time, that is, unless it is a subject to measurement. The science of measurement is an indispensable ingredient in all scientific fields. Mathematical foundations and interpretation of the measurement science were accepted and further developed in most of the scientific fields, including physics, cosmology, geology, environment, quantum mechanics, statistics, and metrology. In this year, 2020, Measurement Science Review celebrates its 20th anniversary and we are using this special opportunity to highlight the importance of measurement science and to express our faith that the journal will continue to be an excellent place for exchanging bright ideas in the field of measurement science. As an illustration and motivation for usage and further development of mathematical methods in measurement science, we briefly present the simple least squares method, frequently used for measurement evaluation, and its possible modification. The modified least squares estimation method was applied and experimentally tested for magnetic field homogeneity adjustment.

Keywords

  • Measurement science
  • linguistic interpretation
  • measuring process
  • physical phenomena
  • measurement evaluation
  • magnetic field
access type Open Access

On Robust Estimation of Error Variance in (Highly) Robust Regression

Published Online: 24 Feb 2020
Page range: 6 - 14

Abstract

Abstract

The linear regression model requires robust estimation of parameters, if the measured data are contaminated by outlying measurements (outliers). While a number of robust estimators (i.e. resistant to outliers) have been proposed, this paper is focused on estimating the variance of the random regression errors. We particularly focus on the least weighted squares estimator, for which we review its properties and propose new weighting schemes together with corresponding estimates for the variance of disturbances. An illustrative example revealing the idea of the estimator to down-weight individual measurements is presented. Further, two numerical simulations presented here allow to compare various estimators. They verify the theoretical results for the least weighted squares to be meaningful. MM-estimators turn out to yield the best results in the simulations in terms of both accuracy and precision. The least weighted squares (with suitable weights) remain only slightly behind in terms of the mean square error and are able to outperform the much more popular least trimmed squares estimator, especially for smaller sample sizes.

Keywords

  • High robustness
  • robust regression
  • outliers
  • variance of errors
  • least weighted squares
  • simulation
access type Open Access

Research on Modified Algorithms of Cylindrical External Thread Profile Based on Machine Vision

Published Online: 24 Feb 2020
Page range: 15 - 21

Abstract

Abstract

In the non-contact detection of thread profile boundary correction, it remains challenging to ensure that the thread axis intersects the CCD camera axis perpendicularly. Here, we addressed this issue using modified algorithms. We established the Cartesian coordinate system according to the spatial geometric relationship of the thread. We used the center of the bottom of the thread as the origin, and the image of the extreme position image was replaced by the image of the approximate extreme position. In addition, we analyzed the relationship between the boundary of the theoretical thread image and the theoretical profile. We calculated the coordinate transformation of the point on the theoretical tooth profile and the coordinate function of the point on the boundary of the theoretical image. At the same time, the extreme value of the function was obtained, and the boundary equation of the theoretical thread image was deduced. The difference equation between the two functions was used to correct the boundary point of the actual thread image, and the fitting results were used to detect the key parameters of the external thread of the cylinder. Further experiment proves that the above algorithm effectively improves the detection accuracy of thread quality, and the detection error of main geometric parameters is reduced by more than 50 %.

Keywords

  • Theoretical tooth profile
  • theoretical image boundary
  • actual tooth profile
  • actual image boundary
  • machine vision
  • difference equation
  • screw thread image processing
access type Open Access

Automatic Strain Gauge Balance Design Optimization Approach and Implementation Based on Integration of Software

Published Online: 24 Feb 2020
Page range: 22 - 34

Abstract

Abstract

The traditional wind tunnel strain balance design cycle is a manual iterative process. With the experience and intuition of the designer, one solution that meets the design requirements can be selected among a small number of design solutions. This paper introduces a novel software integration-based automatic balance design optimization system (ABDOS) and its implementation by integrating professional design knowledge and experience, stepwise optimization strategy, CAD-CAE software, self-developed scripts and tools. The proposed two-step optimization strategy includes the analytical design process (ADP) and the finite element method design process (FEDP). The built-in optimization algorithm drives the design variables change and searches for the optimal structure combination meeting the design objectives. The client-server based network architecture enables local lightweight design input, task management, and result output. The high-performance server combines all design resources to perform all the solution calculations. The development of more than 10 balances that have been completed and a case study show that this method and platform significantly reduce the time for design evaluation and design-analysis-redesign cycles, assisting designers to comprehensively evaluate and improve the performance of the balance.

Keywords

  • Strain gauge balance
  • automatic design
  • structural optimization
  • software integration
  • optimization strategy
access type Open Access

Two-Stage Kalman Filter for Fault Tolerant Estimation of Wind Speed and UAV Flight Parameters

Published Online: 24 Feb 2020
Page range: 35 - 42

Abstract

Abstract

In this study, an estimation algorithm based on a two-stage Kalman filter (TSKF) was developed for wind speed and Unmanned Aerial Vehicle (UAV) motion parameters. In the first stage, the wind speed estimation algorithm is used with the help of the Global Positioning System (GPS) and dynamic pressure measurements. Extended Kalman Filter (EKF) is applied to the system. The state vector is composed of the wind speed components and the pitot scale factor. In the second stage, in order to estimate the state parameters of the UAV, GPS, and Inertial Measurement Unit (IMU) measurements are considered in a Linear Kalman filter. The second stage filter uses the first stage EKF estimates of the wind speed values. Between these two stages, a sensor fault detection algorithm is placed. The sensor fault detection algorithm is based on the first stage EKF innovation process. After detecting the fault on the sensor measurements, the state parameters of the UAV are estimated via robust Kalman filter (RKF) against sensor faults. The robust Kalman filter algorithm, which brings the fault tolerance feature to the filter, secures accurate estimation results in case of a faulty measurement without affecting the remaining good estimation characteristics. In simulations, noise increment and bias type of sensor faults are considered.

Keywords

  • Unmanned aerial vehicle
  • Kalman filter
  • fault detection
  • wind speed
  • GPS
  • pitot tube
access type Open Access

Investigation of Phase Pattern Modulation for Digital Fringe Projection Profilometry

Published Online: 24 Feb 2020
Page range: 43 - 49

Abstract

Abstract

The fringe projection profilometry with sinusoidal patterns based on phase-shifting algorithms is commonly distorted by the nonlinear intensity response of commercial projector. In order to solve this issue, sinusoidal width modulation is presented to generate binary sinusoidal patterns for defocusing the projection. However, the residual errors in the phase maps are usually notable for highly accurate three-dimensional shape measurements. In this paper, we propose the fringe patterns of the sinusoidal, square, and triangular periodic waveforms with seven-step phase-shifting algorithm to further improve the accuracy of three-dimensional profile reconstruction. The absolute phase values are calculated by using quality guided path unwrapping. We learn that by properly selecting fringe patterns according to the target shape, the undesired harmonics of the measured surface have negligible effect on the phase values. The experiments are presented to verify the imaging performances of three fringe patterns for different testing targets. The triangular fringe patterns are suitable for the shape measurements of complex targets with curved surfaces. The results provide a great possibility for high-accuracy shape measurement technique with wider measuring depth range.

Keywords

  • Digital imaging
  • fringe projection
  • waveform

Plan your remote conference with Sciendo