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An overview of the existing methods for measuring the liquid level and their disadvantages in the case of surface vibrations is presented. A system for continuous measurement of the mass of liquids in fuel tanks and tanks during rolling and tilting of vehicles and ships, implemented in a level gauge based on intelligent sensors, is proposed. The sensors include a microcontroller with an individual calibration characteristic of the volume-level dependence, taking into account the shape of the tank or fuel tank, and nanosensors built into the intelligent sensor (ID) for measuring density, permittivity and ambient temperature. It is established that the actual metrological characteristics of the ID are significantly higher than the characteristics of traditional sensors. The number and dimensions of the plates of flat capacitors are justified and the scheme of their arrangement on the roof of the tanks is presented. The exclusion of movable elements increased the reliability of operation, simplified maintenance and design requirements of the measuring object. Analytical expressions for calculating the level and mass of the liquid, implemented by the microcontroller, are given. The use of the proposed measurement system with complex computational processing and taking into account corrections for temperature, density, humidity and permittivity of the liquid made it possible to increase the accuracy and stability of the level meter readings. Analytical expressions are derived that relate the liquid level and the output frequency of the generator from the composition of the level gauge.

The electric load measurement system is a device designed to measure and monitor electricity consumption. In this research, the comparison process of reading the electric current uses the Non-Invasive current sensor model SCT013 and the Invasive current sensor model ACS712 which is connected to the load of electricity consumption. The microcontroller used is the Arduino Microcontroller which functions as the main control system that will be connected to the computer. With the aim later to be able to determine which current sensor is suitable and accurate in reading the electric current. By conducting experiments on the variables of two current sensors, in order to obtain the results of the comparison of the measurement and monitoring of the non-invasive current sensor model SCT013 with the Invasive current sensor model ACS712. Researchers hope to get how much the error percentage value or error of two non-invasive current sensors model SCT013 with Invasive current sensor model ACS712, so that later we can find the right sensor to get the right data for measuring tools, and can be used to monitor energy consumption. electricity that we use

The positioning error of the moving stage has a significant influence on the machining accuracy of a machine tool. Therefore, the positioning error must be measured accurately. Laser interferometer systems are widely used for positioning error calibration due to their accuracy, but these systems also have many shortcomings in standard procedure and measurement methods. In this study, a positioning error measurement system for a long linear stage by using geometric optics rather than interference principles is proposed. However, as the stage moves, geometric errors apart from the positioning error are produced. Accordingly, the proposed measurement system is designed to not only measure the positioning error but also simultaneously measure the multi-degree-of-freedom (MDOF) geometric errors of the linear stage. The proposed measurement system was characterized numerically by using the commercial software Zemax; the mathematical model of the errors was constructed by using a skew-ray tracing method, a homogeneous transformation matrix, and a first-order Taylor series expansion. The feasibility and effectiveness of the proposed measurement system were experimentally verified by using a laboratory-built prototype. The experimental results demonstrate that compared with conventional laser interferometers, the proposed measurement system has similar accuracy and can simultaneously measure the six-degree-of-freedom (6-DOF) geometric errors of a long linear stage.

Prolonged driving causes symptoms of fatigue in drivers and changes their physical condition during driving. The purpose of this paper is to use a force measurement system located in the driver’s seat by force-sensitive resistance pressure sensors in order to record the received information to predict fatigue by learning regression-based models. This system is designed with 16 FSR (Force Sensing Resistor) sensors mounted on the seat and its backrest that records the driver’s body’s data, based on the force exerted by the driver on the seat in standard mode and during driving at various times. Fatigue level prediction is based on the trained nonlinear autoregressive exogenous model. In this procedure, models based on multivariate regression are first trained, and then correctness is checked. In this paper, the fatigue index is divided into five parts from 0 to 100 included fully conscious, slightly tired, moderately tired, very tired, and extremely tired, so the criterion for diagnosis is crossing the 75% of fatigue index and entering the extremely tired range. The results show that nonlinear models based on exogenous autoregressive have better performance than the linear mode, and even in the nonlinear model of NARX neural network, the fatigue of one step ahead is well predictable. A flopped state will be predictable when the body is immersed in the seat due to fatigue, so is far from the standard sitting position and will be in the extremely tired warning range.

The article analyzes the report documentation of the tests in which the Doppler radar trajectory measurement system MFTR–2100/40 and the muzzle velocity measurement system SL-520PE were used to determine the trajectory parameters of artillery armament. The purpose of the article is to provide proposals for standard methods of using Doppler radar systems of trajectory measurements when testing artillery armament and its ammunition. The proposals for these standard methods are based on the experience of using the MFTR–2100/40 radar system and the SL–520PE muzzle velocity measurement system during the tests of the latest specimens of artillery and ammunition and relate to typical Doppler radar systems. When choosing the position and mode of operation of such Doppler radar trajectory measurement systems, it is always necessary to take into account safety measures, instructions for their operation, technical features (capabilities) of radar systems specified in this article, considering the interference environment during firing (shot) of artillery armament and experiment (test) conditions. Placing typical Doppler radar systems when taking measurements in unplanned places is dangerous for the crew and measuring instruments and leads to partial or complete loss of measuring trajectory information and reduced measurement accuracy. Abovementioned proposals are offered to be taken into account when developing methods of trajectory measurements using typical Doppler radar systems during testing artillery armament and its ammunition. Methods of measurements using standard Doppler radar systems of trajectory measurements should be developed in accordance with current standards (GOST 8.010-99, GOST V 15.211-78 and others) for a particular test, taking into account the results of analysis of the characteristics of samples to be evaluated, measuring instruments used, conditions and locations of measurements.

В роботі проведено аналіз сучасного стану існуючої лабораторної бази бортових інформаційно-вимірювальних комплексів та реєструючих систем, які застосовуються для збору, обробки, відображення параметрів і характеристик дослідних зразків озброєння та військової техніки різного функціонального призначення, їх складових частин з метою контролю функціонування, контролю змін параметрів та визначення помилкових дій екіпажів на об’єкти випробувань. Метою статті є аналіз сучасного стану лабораторної бази бортових інформаційно-вимірювальних комплексів і реєструючих систем та визначення загальних вимог до систем бортових вимірювань для проведення випробувань озброєння та військової техніки різного функціонального призначення. Методом проведення дослідження є системний аналіз. Розглянуто характеристики означеного обладнання та варіанти розміщення і комутації у складі дослідного зразка. Визначено основні параметри для автомобільної та бронетанкової техніки, які підлягають реєстрації (вимірюванню) за допомогою бортових інформаційно-вимірювальних комплексів. Запропоновано варіант конфігурації бортової реєструючої системи на основі модулів та інтерфейсів фірми Racelogic Adas. За результатами проведеного аналізу зроблено висновки щодо використання засобів реєстрації і систем бортових вимірювань, для проведення випробувань озброєння та військової техніки різного функціонального призначення науково-дослідними лабораторіями Збройних Сил та підприємств промисловості України. Отримані результати дослідження доцільно застосовувати при обґрунтуванні загальних вимог до сучасної універсальної системи бортових вимірювань для проведення випробувань озброєння та військової техніки різного функціонального призначення.

On-board information and measuring complexes and registration systems are intended to control the parameters of both systems and components of the prototype and the sample of automotive and armored vehicles in general to obtain qualitative and quantitative characteristics to assess their compliance with specifications of technical development requirements. At present stage, there is often a need to improve methods for optimizing the development of on-board systems for collecting and processing information to ensure conducting of testing works, which take into account particulars of the electronic equipment development and are based on a unified approach to the optimal use of resources of collection and information processing systems. Analysis of the problem of rational use of resources of standard means of measurement, registration and indication in the system of onboard measurements and further processing of the results in automated systems for collecting and processing information for their use in testing mass produced (modernized) aircraft was previously considered by Soviet, Ukrainian and foreign scientists. But they do not give a complete picture of the algorithm, completeness and quality of tests using standard measuring instruments installed on board aircraft and do not answer a number of questions related to the optimization of the computational process. In particular, the potentials of standard means of measurement, registration and indication as part of the on- board measurement system for testing mass produced (modernized) aircraft and installed components, units and systems under test are not fully explored. The issue of building optimal data collection programs that implement the inquiry of measuring channels with restrictions on the frequency of channel inquiry and information processing speed is insufficiently studied. The novelty of the research consists in the developing of an algorithm for capabilities analysis and procedure for incorporating standard measuring, registration and indication instruments in the on-board measuring system within a single measuring and information field for testing mass produced (modernized) samples of weapons. Approbation and implementation of the abovementioned algorithms will allow test teams to minimize time spent on the development (selection) of the onboard measurement system to ensure research and testing of both modernized aircraft, vehicles and armored vehicles and newly created with advanced information systems.

Unmanned aerial vehicles (UAVs) are being explored by researchers to measure concentrations of gas emissions in situations where such measurements are otherwise extremely difficult to obtain, such as NO and NO2 (NOx) emissions from surface mine blasting. Recently, countries have imposed or are planning to impose surface blasting gas pollution regulations, which creates a need for an improved understanding of UAV-based gas measuring systems. The experiments detailed in this paper were performed to determine if airflow generated by the rotors, also known as downwash, unnaturally alters concentration measurements. Downwash turbulence could create locations of varying pressure, which could affect concentration. A UAV fitted with gas sensors was attached to a stand in a controlled environment containing a mixture of NOx. The gas sensor measuring points were placed at various distances on and from the UAV body to evaluate downwash effects on gas concentration. Results show that the presence of downwash turbulence causes no statistically significant changes to concentration measurements at any distance or direction from the UAV. Based on these results, it is possible to use a UAV-mounted gas monitor to measure concentrations without concern for downwash interference, provided the UAV and measuring point are entirely contained within the gas cloud.

An intra-measurement evaluation was undertaken, deploying a NOMAD buoy equipped with three National Data Buoy Center and two Environment and Climate Change Canada-AXYS sensor/payload packages off Monterey, California; a Datawell Directional Waverider buoy was deployed within 19 km of the NOMAD site. The six independent wave measurement systems reported hourly estimates of the frequency spectra, and when applicable, the four Fourier directional components. The integral wave parameters showed general agreement among the five sensors compared to the neighboring Datawell Directional Waverider, with the Inclinometer and the Watchman performing similarly to the more sophisticated 3DMG, HIPPY, and Triaxys sensor packages. As the Hm0 increased, all but the Inclinometer were biased low; however, even the Watchman reported reasonable wave measurements up to about 6–7 m, after which the Hm0 becomes negatively biased up to about a meter, comparable to previous studies. The parabolic fit peak spectral wave period, Tpp, results showed a large scatter, resulting from the complex nature of multiple swell wave systems compounded by local wind-sea development, exacerbated by a variable that can be considered as temporally unstable. The three directional sensors demonstrated that NOMAD buoys are capable of measuring directional wave properties along the western US coast, with biases of about 6 to 9 deg, and rms errors of approximately 30 deg. Frequency spectral evaluations found similarities in the shape, but a significant under estimation in the high frequency range. The results from slope analyses also revealed a positive bias in the rear face of the spectra, and a lack of invariance in frequency as suggested by theory.

Optoelectronic oscillators (OEO) based sensors generate low-phase-noise signals, whose frequency is in the order of GHz. These sensors are highly sensitive to parameters like strain, transverse load or temperature. Particularly, an OEO transforms a wavelength change into a frequency shift in the order of MHz. This creates a particular challenge for measuring instruments used in OEO, where novel mathematical methods for advanced processing of their signals is required. The principle of rational approximations is a frequency measurement technique based on number theory, with the fundamental property of measurement time dependent on the frequency value of input signals. This means that if the frequency of input signals increases, less time for measuring is required. This is quite useful for time-frequency measurement systems, where if more accuracy is needed, more time is required for measuring. This paper shows how the principle of rational approximations can be used in OEO based sensors, this allows to estimate the frequency shifts in a bandwidth from 6 to 600 MHz, with a maximum uncertainty of 2.5 MHz. Such an accuracy is achieved in a time as short as $0.2~\mu \text{s}$ .

The analysis based on geospatial data from different measurement systems now constitutes a complex numerical and practical enterprise. The dynamic development of modern technologies enables rapid a...

In recent years, with the increasing application of human motion monitoring technology in virtual reality, medical health, human-computer interaction, and other fields, higher requirements have been put forward for measurement accuracy. Aiming at the problem of large accumulative measurement error and multi-joint constraint in the traditional inertial measurement system, a multi-joint constrained filter model human motion monitoring method based on data fusion is proposed. Firstly, an accelerometer and magnetometer are used to construct the initial attitude angle calculation model of the human body at rest. Secondly, combined with gyroscope, accelerometer and magnetometer, the attitude optimal estimation model based on Extended Kalman Filter (EKF) algorithm for human body motion was established. Then, a global coordinate system of human multi-joints is established, and the joint constraint is introduced into the attitude optimal estimation model by using the estimation projection method, and the multi-joint constraint filtering model of human motion monitoring is constructed. Finally, a multi-inertial measurement unit (MIMU) human motion monitoring system was built, and the simulation and experimental analysis were carried out. The experimental results show that the maximum angular measurement error is about 1° after filtering with the motion monitoring method proposed in this paper. Compared with the existing algorithm, the accuracy of the three angle measurements is improved by 38.2%, 39.3% and 67.4%, respectively. Based on this, the human motion monitoring system designed can effectively monitor human motion.

A method for optimizing the wavefront errors of detected radiation in the optical system of a large-sized telescope (LST) based on the redistribution of errors over the image field is developed. On the example of a cryotelescope having a diameter of 12 m, the problem of optimizing a uniform distribution of aberrations over the image field in an LST was solved by varying the parameters of the secondary mirror in the Zemax-EE software package. The results of calculating optical assemblies using the traditional method and the proposed method for optimizing the errors of the radiation wavefront are presented. The advantages and disadvantages of both methods are considered.

Aiming at the problem that the lattice feature exceeds the view field of the scanning electron microscope (SEM) measuring system, a new lattice measuring method is proposed based on integral imaging technology. When the system works, the SEM measuring system is equivalent to an integral image acquisition system. Firstly, a lattice measuring method is researched based on integral imaging theory. Secondly, the system parameters are calibrated by the VLSI lattice standard. Finally, the value of the lattice standard to be tested is determined based on the calibration parameters and the lattice measuring algorithm. The experimental results show that, compared with the traditional electron microscope measurement method, the relative error of the measured value of the algorithm is maintained within 0.2%, with the same level of measurement accuracy, but it expands the field of view of the electron microscope measurement system, which is suitable for the measurement of samples under high magnification.

In this study, the machine-vision technique is employed to measure the angle between two circular holes for the derailleur parts of a bicycle. A delta robot equipped with a motorized zoom lens is constructed as an automatic measurement device. In this way, we can detect the normal vectors of circular holes with different positions and sizes by using only one camera. By calculating the plane normal vectors of two circular holes within the camera coordinate system and performing the cross-product operation, the angle between the two circular holes is obtained. Simulation experiments reveal that the measurement method is influenced by the projection eccentricity error, and the error can be reduced by increasing the focal length and employing the virtual-center alignment method. The results show that the average error for measuring the derailleur parts is approximately 0.061°, and the standard deviation is 0.112°. Experimental analysis indicates that while the magnification of the image is larger, the average error of the measurement result is reduced, and the standard deviation is reduced as well. When the magnification is 0.4×, the measurement average error is 0.04°, and standard deviation is 0.101°. When the distance between the center of the circle and the center of the image is increased, the error in the angle calculation is also increased. A significant improvement is obtained by setting the fitting center position to the optical central position, which omits the influence of the error amplification caused by the distance of the circular hole from the optical axis.

Aiming at the problems that the weak current signal circuit is susceptible to noise interference and leakage current at the input terminal affects the measurement accuracy, a weak current measurement error correction scheme based on the combination of wavelet threshold denoising and generalized regression neural network (GRNN) was proposed. The scheme was applied to the error correction of multi-channel weak current measurement system based on the ADAS1134 chip: the wavelet threshold denoising was used to preprocess the original current data measured by the system and the current measurement value was corrected after the system measurement error correction model established with GRNN was constructed. Compared with the correction method based on least square method and back propagation neural network (BPNN), this method has many advantages such as high accuracy, anti-interference ability and strong generalization ability. The experimental results showed that RMSE=0.0911 nA, MAE=0.0354 nA, and MAPE=0.0078%, without increasing the complexity of the measurement circuit, which achieved the purpose of correcting the measurement error of the weak current measurement system.

A special design of the measuring cell was proposed, which makes it possible to determine the optical and electrochemical characteristics of thin-film electrochromic electrodes simultaneously. Also, the proposed cell provides constant temperature control using a small-sized thermostating unit built on Peltier elements and digital boards of W1209 thermostats. The cell was made using 3D printing with ABS plastic by the fused deposition method (FDM), followed by a sealing stage using a solution of polymethyl methacrylate dissolved in dichloroethane. In the course of the research, the use of a green laser with a wavelength of 520nm was substantiated. Separately, the linearity of optical readings, the dependence of the indicators of the optical characteristics measurement system on temperature, as well as the uniformity of electrolyte heating in the cell, were studied. In addition, the pattern of the electric field was determined, which was an indicator of the uniformity of the current density distribution on the measured electrode. The obtained dependences made it possible to assert that the characteristics of the cell and the measuring system as a whole are suitable for the stated research purposes. It was also shown that the cost of the cell, together with the optical measuring system and the constant temperature control system, is more than two times cheaper than simple electrochemical cells offered by manufacturers. The proposed algorithm for the development of the cell design, the approach to the selection of components, as well as the given technical details, allow us to manufacture measuring equipment for the specific goals of the researcher. In this case, the given schematic, structural, and hardware solutions can be used separately from each other

Цель исследования – создание нового решения по автоматизации отслеживания местоположения внутритрубных объектов при его движении в трубопроводе. Выполнены следующие задачи: разработаны алгоритм отслеживания точного местоположения, логические программы работы эмулятора, панель оператора системы отслеживания местоположения внутритрубных объектов. Предложенное решение по автоматизации отслеживания местоположения внутритрубных объектов позволитповысить эффективность обслуживания трубопроводов. В результате разработана информационно-измерительная система отслеживания местоположения средств очистки и диагностики трубопроводов на базе ПЛК SIEMENS серии SIMATIC S7 -1200/1500. The purpose of this article is to develop a new solution for automating the tracking of the location of in-line objects during its movement in the pipeline. The following tasks were completed: an algorithm for tracking the exact location, logical programs for the emulator, and a virtual model of the system for tracking the location of in-line objects were developed. Hypothesis: the proposed solution for automating the tracking of the location of in-line facilities makes it possible to increase the efficiency of pipeline maintenance. As a result, an information and measurement system for tracking the location of pipeline cleaning and diagnostics tools based on the SIEMENS SIMANTIC S7 -1200/1500 series PLC was developed.

Open-path measurements of atmospheric composition provide spatial averages of trace gases that are less sensitive to small-scale variations and the effects of meteorology. In this study we introduce improvements to open-path near-infrared (OP-NIR) Fourier transform spectrometer measurements of CO2 and CH4. In an extended field trial, the OP-NIR achieved measurement repeatability 6 times better for CO2 (0.28 ppm) and 10 times better for CH4 (2.1 ppb) over a 1.55 km one-way path than its predecessor. The measurement repeatability was independent of path length up to 1.55 km, the longest distance tested. Comparisons to co-located in situ measurements under well-mixed conditions characterise biases of 1.41 % for CO2 and 1.61 % for CH4 relative to in situ measurements calibrated to World Meteorological Organisation – Global Atmosphere Watch (WMO-GAW) scales. The OP-NIR measurements can detect signals due to local photosynthesis and respiration, and local point sources of CH4. The OP-NIR is well-suited for deployment in urban or rural settings to quantify atmospheric composition on kilometre scales.

In this paper, a high-efficiency self-calibration method was proposed, which was successfully applied to the ultra-precision air-bearing motion stage. Firstly, digital grating focusing, camera vision measurement and position synchronous output signal control were integrated, which can effectively improve the acquisition accuracy of stage positional data. Then, based on the least square algorithm the systematic error compensation value of motion stage can be quickly obtained through the fitting processing of three different measurement views. The experimental results showed that the proposed self-calibration measurement system can successfully realize ultra-precision air-bearing stage accurate location, and the orthogonality and shrinkage were controlled within 1 arcsec and 300 nm, respectively. This compensation method can effectively avoid the problems of high cost and poor environmental anti-interference in the laser interferometer measurement system, and will have a broad application prospect in the fields of high-end lithography and ultra-precision machining.

SUMMARY Microbarometers deployed to measure atmospheric infrasound are often connected to, or housed within, a wind noise reduction system (WNRS). At infrasound arrays of the International Monitoring System (IMS), being deployed as part of Comprehensive Nuclear-Test-Ban Treaty verification measures, the WNRS typically comprises an 18 m diameter pipe array. Over the past decade an in situ method has been developed to estimate the measurement system (sensor + WNRS) response characteristics, by comparing its recordings with those made on a colocated reference sensor with known response and no WNRS. The method relies upon the identification of time periods for which the reference sensor and measurement system are subject to the same input pressure field. It has proven difficult to reliably identify such time periods at frequencies $\lt 0.1\,$ Hz using recordings at a single location, resulting in a negative bias in estimated measurement system gain values (the ‘dip artefact’) in the 0.02–0.1 Hz passband. The IMS is deploying arrays of microbarometers, and we show that a measure of across-array coherence can be used to identify time periods associated with acoustic signal propagation. Amplitude response estimates, using 1 yr of data from four IMS arrays, indicate that the dip artefact can be removed by retaining for analysis only those time periods that exhibit high across-array coherence. Moreover, our analysis confirms the hypothesis that the dip artefact is associated with time periods during which wind-generated pressure fluctuations dominate, leading to partial suppression of noise with length scales less than the extent of the WNRS. At two arrays within continental forests accurate amplitude responses are estimated across the 0.02–4 Hz passband, as acoustic signals at all frequencies can be identified. At two oceanic island arrays, the low numbers of time windows with above-noise acoustic signal in the 0.02–0.1 Hz passband make reliable response estimation at these frequencies difficult or impossible. It is recommended that the methodology for estimating the response of an infrasound measurement system at an array should incorporate a multichannel coherence measure; data centres may already routinely compute such measures in their signal detection algorithms.

The dynamic characteristics of the XY worktable are thoroughly analyzed in this study to accurately compensate the measurement errors of on-machine measurement systems caused by the dynamic and static characteristics under multiple factors. The dynamic positioning error model of the XY worktable motion components is established, and the theoretical model of the dynamic positioning error of the XY worktable is derived. The actual parameters of the experimental platform for the correlation error of CNC machine tools are substituted into the model for theoretical calculation and analysis. Results show that the motion speed of the worktable, the weight of the measured workpiece, the installation position of the workpiece, and the friction force are the main factors causing the dynamic positioning error. Dynamic positioning error analysis and verification experiments were conducted to verify the validity of the proposed theoretical model. Experimental results show that a regular change occurs between the dynamic positioning error and the movement speed of the XY worktable, and the actual measurement results are basically consistent with the theoretical calculation results. The research results can lay a good foundation for establishing the measurement error prediction and compensation model of on-machine measurement systems of CNC machine tools and improving its measurement accuracy.

In recent years, multiple applications have emerged in the area of payload transport using unmanned aerial vehicles (UAVs). This has attracted considerable interest among the scientific community, especially the cases involving one or several rotary-wing UAVs. In this context, this work proposes a novel measurement system which can estimate the payload position and the force exerted by it on the UAV. This measurement system is low cost, easy to implement, and can be used either in indoor or outdoor environments (no sensorized laboratory is needed). The measurement system is validated statically and dynamically. In the first test, the estimations obtained by the system are compared with measurements produced by high-precision devices. In the second test, the system is used in real experiments to compare its performance with the ones obtained using known procedures. These experiments allowed to draw interesting conclusions on which future research can be based.

Air pollution is one of the global problems of the current era. According to World Health Organization more than 80% of the people living in metropolitan areas breathe air which exceeds the guideline limits. Particulate matter, the mixture of liquid and solid particles having diameters less than 10 mu m, is one of the important pollutants in the air. The main source of the Particulate matter is mostly burning reactions associated with industry, vehicles and homes. Several studies have shown the lethal impact of particulate matter to public health and environment. The rise of particulate matter amount in air has been linked to several health problems such as not only respiratory diseases but also mortality in infants and heart attacks. Currently, bulky stations which are high-cost and have limited spatial resolution are used to monitor the air quality. In this study we developed an alternative particulate matter measurement system which is portable and low-cost (less than 200 USD) and also integrated with cloud computing. The system allows real time distant monitoring of PM particles with high spatial resolution (meter range). The developed sensor system is able to provide air quality data in correlation with the existing stations (R-2 = 0.87). The statistical comparison between the developed system and the reference methods revealed that two systems produced statistically equal results in detecting the variations of the particulate matter.

Purpose This paper aims to propose a measurement principle and a calibration method of measurement system integrated with serial robot and 3D camera to identify its parameters conveniently and achieve high measurement accuracy. Design/methodology/approach A stiffness and kinematic measurement principle of the integrated system is proposed, which considers the influence of robot weight and load weight on measurement accuracy. Then an error model is derived based on the principle that the coordinate of sphere center is invariant, which can simultaneously identify the parameters of joint stiffness, kinematic and hand-eye relationship. Further, considering the errors of the parameters to be calibrated and the measurement error of 3D camera, a method to generate calibration observation data is proposed to validate both calibration accuracy and parameter identification accuracy of calibration method. Findings Comparative simulations and experiments of conventional kinematic calibration method and the stiffness and kinematic calibration method proposed in this paper are conducted. The results of the simulations show that the proposed method is more accurate, and the identified values of angle parameters in modified Denavit and Hartenberg model are closer to their real values. Compared with the conventional calibration method in experiments, the proposed method decreases the maximum and mean errors by 19.9% and 13.4%, respectively. Originality/value A new measurement principle and a novel calibration method are proposed. The proposed method can simultaneously identify joint stiffness, kinematic and hand-eye parameters and obtain not only higher measurement accuracy but also higher parameter identification accuracy, which is suitable for on-site calibration.

During the research phase of acrylic panel for the Jiangmen Underground Neutrino Observatory (JUNO) central detector (CD), the darkroom transmittance measurement system (DTMS) was designed and built, and a massive amount of measurements were carried out to help determine the composition and processing techniques of the acrylic panel. The mass production of acrylic panels was started after the pilot production. The requirement of transmittance measurement put forward new demands on operation, and a new measurement system was considered to support removable and non-destructive measurement on site. After the accomplishment of design, development and verification were completed, the laser measurement system came into use in the acrylic workshop of Taixing Donchamp Acrylic Ltd, and the transmittance results of acrylic spherical panels met the requirement of JUNO. The optical design, tooling design, data processing interface and uncertainty analyses of the laser measurement system are discussed in detail, and the measured transmittance results are also introduced in this article.

Surface wear of drilling bit in the drilling process is complex, and the traditional wear index is not suitable to reflect the wear condition of drilling bit well; it is necessary to investigate on the appropriate wear testing and evaluation method. In this paper, a visual measurement system is set up to obtain the drilling bit wear characteristics based on machine vision. The wear area image is grayscale processed, and the gray image is thresholding segmentation processed, then the boundary feature is extracted based on the chain code method. A comprehensive evaluation system is established, in which the wear perimeter, the equivalent wear diameter, and maximum wear width of different areas are proposed as the wear indicators. The wear fusion feature based on the principal component analysis is proposed to characterize the drilling bit wear degree, the wear indicators of different regions are characterized and fused as the wear degree of different regions, then the prediction model of the drilling bit wear degree is established based on support vector machine. The results show that the predicted results are mainly consistent with the experimental results. The research of the drilling bit wear characteristics based on principal component analysis can provide guidance for the study of drilling bit wear mechanism.

When performing remote tasks using robots in nuclear power plants, a 3D shape measurement system is advantageous in improving the efficiency of remote operations by easily identifying the current state of the target object for example, size, shape, and distance information. Nuclear power plants have high-radiation and underwater environments therefore the electronic parts that comprise 3D shape measurement systems are prone to degradation and thus cannot be used for a long period of time. Also, given the refraction caused by a medium change in the underwater environment, optical design constraints and calibration methods for them are required. The present study proposed a method for developing an underwater 3D shape measurement system with improved radiation tolerance, which is composed of commercial electric parts and a stereo camera while being capable of easily and readily correcting underwater refraction. In an effort to improve its radiation tolerance, the number of parts that are exposed to a radiation environment was minimized to include only necessary components, such as a line beam laser, a motor to rotate the line beam laser, and a stereo camera. Given that a signal processing circuit and control circuit of the camera is susceptible to radiation, an image sensor and lens of the camera were separated from its main body to improve radiation tolerance. The prototype developed in the present study was made of commercial electric parts, and thus it was possible to improve the overall radiation tolerance at a relatively low cost. Also, it was easy to manufacture because there are few constraints for optical design.

Most thickness measurement techniques using X-ray radiation are unsuitable in field processes involving fast-moving organic films. Herein, we propose a Compton scattering X-ray radiation method, which probes the light elements in organic materials, and a new simple, non-destructive, and non-contact calibration-free real-time film thickness measurement technique by setting up a bench-top X-ray thickness measurement system simulating a field process dealing with thin flexible organic films. The use of X-ray fluorescence and Compton scattering X-ray radiation reflectance signals from films in close contact with a roller produced accurate thickness measurements. In a high-thickness range, the contribution of X-ray fluorescence is negligible, whereas that of Compton scattering is negligible in a low-thickness range. X-ray fluorescence and Compton scattering show good correlations with the organic film thickness (R2 = 0.997 and 0.999 for X-ray fluorescence and Compton scattering, respectively, in the thickness range 0–0.5 mm). Although the sensitivity of X-ray fluorescence is approximately 4.6 times higher than that of Compton scattering, Compton scattering signals are useful for thick films (e.g., thicker than ca. 1–5 mm under our present experiment conditions). Thus, successful calibration-free thickness monitoring is possible for fast-moving films, as demonstrated in our experiments.

Force measurement on steel wire rope (SWR) is significant to ensure the safety of people and property. Previous methods propose the electro-magnetic sensor, which measures the force applied on the SWR non-invasively and does not damage the structure of the SWR. Based on the magneto-elastic effect and integration of induction voltage as the indicator, electro-magnetic sensors perform well in many situations. However, in practice, the integration of induction voltage method is noise-sensitive, because the noise is easily accumulated by integration in the practical environment. In this case, we propose an improved method based on a novel indicator, maximal induction voltage. The maximal induction voltage method is influenced less by noise, as no integration of noise term is involved, so the maximal induction voltage method has better performance on noise reduction. Moreover, the paper builds a force measurement system by deriving the analytical linear relation between force and maximal induction voltage, and this linear relation can be estimated by prior experimental data. The experimental results show that the proposed method has higher linearity and sensitivity than the integration of induction voltage method.

In this paper, a novel launch dynamics measurement system based on the photoelectric sensor pair is built. The actual muzzle time (i.e. a time duration that originates from the initial movement to the rocket’s departure from the muzzle) and the muzzle velocity are measured. Compared with the classical methods, the actual muzzle time is obtained by eliminating the ignition delay. The comparative analysis method is proposed with numerical simulations established by the transfer matrix method for multibody systems. The experiment results indicate that the proposed measurement system can effectively measure the actual muzzle time and reduce the error of classical methods, which match well with the simulation results showing the launch dynamics model is reliable and helpful for further analysis and design of the MLRS.

Many methods have been applied to monitor fugitive methane gas from landfills. Recently, there have been suggestions to use a framework utilizing an unmanned aerial vehicle (UAV) for landfill gas monitoring, and several field campaigns have proved that a rotary UAV-based measurement has advantages of ease of control and high-resolution concentration mapping on the target planes. However, research on the evaluation of error-inducing factors in the suggested system is limited so far. This study prepared a measurement system with a lightweight methane detector and a rotary UAV to support the applicability of rotary UAV in landfill gas monitoring. Then, the validity of the system was tested experimentally and theoretically. In the detector reliability test, the methane detector had sufficient resolution for field application. The critical UAV velocity required was obtained to ensure the credibility of the proposed measurement system. When spatial interpolators were applied to field data from the measurement system, the empirical Bayesian kriging demonstrated the best prediction of methane concentrations at unmeasured points. With the verifications provided in this study, this proposed method may contribute to reducing uncertainty in estimating fugitive landfill gas emission.

This article describes a shape-recognizable sheet device using origami structures with single-walled carbon nanotubes (SWCNTs) strain sensors. Recently, a sheet-like measurement system that is directly attached to an object has been attracting attention for obtaining the shape, motion, and deformation of the object as alternative systems with external cameras. However, previous sheet-like measurement systems are difficult to distinguish between the stretch and the bend of the object appropriately. Here we propose a sheet-like measurement system that can distinguish the stretch and the bend individually by using origami structures. We formed a strain sensor using SWCNTs that was deposited on a substrate to form a 5–7 nm thin film. By patterning the SWCNTs strain sensors, origami-based sheet devices were fabricated. We confirmed that our origami sheet device obtained the bending and stretching information separately by attaching the device to cylinders. We believe that the origami system could contribute to the observation of complex deformations such as artificial skin, human interface, and biomedical applications. [2020-0324]

Annually, numerous cattle die of various diseases, necessitating the need for effective cattle health management. To ensure cattle disease detection at an early stage and identify the health status of cattle, we collected the environment temperature, humidity, illuminance, and infrared images of cattle in an actual-life environment as input parameters to develop an artificial intelligence characterization module for measuring deep body temperature in a contactless manner. By analyzing the correlation of estimating deep body temperature at the horn, eyeball, and nose of cattle, the most effective way of estimating this temperature was found to be at the horn. The estimation accuracy was particularly high in the sitting state. Moreover, we proposed a noncontact measurement system that can approximately measure the moving distance of cattle and depict the cattle movement trajectory. The usability and reliability of the proposed systems were verified via an experiment using special feed. We used moving distance data as an additional input for the body temperature estimation system and found that rumen temperature can be accurately estimated. The body temperature estimated using the proposed system can be used to realize long-term remote monitoring of cattle health and early and timely abnormality detection.

In this article the accuracy of the LRM+ calibration is compared to that of the benchmark NIST multiline TRL procedure for the first time. The comparison is performed on NIST verified GaAs coplanar waveguide calibration reference material 8130. The NIST calibration comparison method is used to quantify the difference between measured S-parameters corrected by NIST multiline TRL and an advanced LRM+ calibration. The worst-case error bounds for LRM+ corrected S-parameter measurements are determined up to 110 GHz. It is demonstrated that the difference between benchmark multiline TRL and LRM+ is comparable with the measurement system drift. Verification results prove that LRM+ can be successfully used for accurate GaAs on-wafer calibration with customized standards. This overcomes some drawbacks of multiline TRL while providing the same calibration accuracy.

Load forecasting can increase the efficiency of modern energy systems with built-in measuring systems by providing a more accurate peak power shaving performance and thus more reliable control. An analysis of an integrated CO2 heat pump and chiller system with a hot water storage system is presented in this paper. Drastic power fluctuations, which can be reduced with load forecasting, are found in historical operation records. A model that aims to forecast the ventilation system heating demand is thus established on the basis of a long short-term memory (LSTM) network. The model can successfully forecast the one-hour-ahead power using records of the past 48 h of the system operation data and the ambient temperature. The mean absolute percentage error (MAPE) of the forecast results of the LSTM-based model is 10.70%, which is respectively 2.2% and 7.25% better than the MAPEs of the forecast results of the support vector regression based and persistence method based models.

In this study, a small sensor for the dynamic measurement of the local moisture content within a wooden member exposed to fire heating is developed. The measurement is based on the unique dependence of the electrical resistance of wood on moisture content and temperature. These relationships are observed experimentally at temperatures between 20°C and 90°C, and moisture content between 6.9% and 232.8%, for Cryptomeria japonica, Larix leptolepis, Pseudotsuga menziesii, and Zelkova serrata. The electrical resistance is represented with the temperature and moisture content for each tree species. The measurement is found to be the most effective within the moisture content of 10%‐30%.

In this paper, we propose a fiber optic system to measure the changes in the RGB composition of light in liquid solutions using a plastic optical fiber (POF) as an intrinsic sensor. The measurement system is composed of a 3 W white light-emitting diode as the light source, a 20 cm long U-shaped POF, and an RGB photodiode array that allows us to detect the changes in the RGB composition of the light propagating through the POF. The U-shaped POF has a length of 5 mm without coating, which remains in contact with the liquid solutions. The tests were performed with different concentrations of a mixture of tequila and water. The results obtained with the RGB photodiode array showed that the system has a resolution of 0.39 % and a color change sensitivity of 0.1, 0.6, and 0.4 8–bits/% of sample for red, green, and blue colors, respectively. These results will allow us to design a low-cost prototype to measure the amount of adulteration in liquids.

The rooftop solar photovoltaic system is one of the potential methods vastly adopted to harness the abundant solar energy and to overcome land limitation. In our previous study, the rooftop solar energy potential has been investigated with a case study of buildings in the University of Bengkulu using drone technology. The estimation results of the study show that all buildings have the potential to be developed as the installation area of solar panels. Moreover, the optimum solar harvest is affected by the inclination of the rooftop. However, the results obtained were estimated power under ideal conditions. Therefore, in this research, the solar mapping potential results were examined using solar panels and current sensors. In the measurement system, the ability of the system to harvest solar energy was evaluated by placing a solar panel on miniature buildings. The placement of the solar panels was adjusted relative to the inclination and orientation of the building rooftop. This experiment was carried out for 24 h to obtain the optimum value for each tilt of the rooftop and orientation of the solar panel surface. The examination results show that the energy harvesting capacity of each solar panel is strongly influenced by the inclination of the rooftop and the orientation of the solar panel surface towards the sun. Solar panels with a smaller tilt angle are able to produce larger average power. Furthermore, the cloud coverage also affects the performance of solar panels in produce electricity.

The results of the development of a gas mixing and analytical stand (reference complex) for testing in order to approve the type of automatic measuring systems (AMS) for determining the content of pollutants in industrial emissions are presented. During the use of the AMS test bench, the units of molar fraction and mass concentration are transferred from the State primary standard of units of molar fraction, mass fraction and mass concentration of components in gas and gas condensate media GET 154 to the tested measuring gas channels of AMS, thereby ensuring traceability of AMS measurement results to the State primary standard GET 154.

The aim of this paper is to present a mixed experimental–numerical approach to evaluate the moisture content (MC) in Douglas fir samples through the use of electrical resistivity measurements. Elevated MC levels constitute the greatest threat to both physical and mechanical properties in timber structures. A reliable MC estimation process is considered a key to ensuring high durability, a long service life and low maintenance costs. In this study, a measurement system typically employed for electrical prospecting in the field of geophysics has been adapted to determine the electrical resistivity of wood. This approach-based tool is essentially a megohmmeter measuring the electrical resistance of wood using two pairs of needle-shaped probes inserted into the material. For this purpose, specific cables and electrodes have been developed. Using samples conditioned in a climate-controlled room, a number of key factors in MC estimation, such as electrode configuration and temperature, were investigated. These results are analyzed in order to both optimize the experimental protocol for future in situ applications and point out the experimental limitations associated with this measurement tool.

A portable emission measurement system (PEMS) was used to measure the real-world driving emissions pertaining to a Japanese middle-sized heavy-duty vehicle. The testing was performed with the vehicle being driven in the metropolitan area of Tokyo in four seasons (January, June, August, and November) to analyze the seasonal dependence of NOx and CO2 emissions. The experimental results indicated that the amount of NOx emissions was particularly high in the cold season owing to the slow starting of the NOx after-treatment systems, which is to say the exhaust gas recirculation and urea-selective-catalytic-reduction systems, under low-ambient-temperature conditions. In real-world driving, a high acceleration pattern was observed in the low-speed region which is not considered in the world harmonized vehicle cycle, which is the worldwide official driving mode in the chassis dynamometer experiment. Finally, the transient emission tables for NOx and CO2 were constructed based on the PEMS measurement results and the classical mechanic theory. The constructed tables replicated well the experimental results in all the considered conditions involving different ambient temperatures and locations. The proposed approach can be used to evaluate emission inventories in the future.

Position and orientation errors of rotary axis average lines are often dominant error sources in the five-axis machining. Many schemes have been studied, and some are now commercially available, such that they can be identified on-machine, and then numerically compensated, by a machine tool user. Many conventional schemes install a measuring instrument or a measured target in a machine spindle, and thus cannot be performed when the spindle is rotating. Rotary axis location errors are often influenced by the machine’s thermal deformation. When the spindle is not rotating, they can be different from actual machining operations. This paper presents the application of a non-contact laser barrier tool measurement system to the identification of rotary axis location errors, when the spindle rotates in the same speed as in actual machining applications. An experimental thermal test is presented to observe the change in rotary axis location errors under continuous machine warm-up by spindle rotation and reciprocal linear axis motions. Experimental comparison with the R-Test, a typical conventional scheme that can be performed only when the spindle does not rotate, shows that rotary axis location errors change quickly after the machine warm-up is terminated.

Рассматриваются математические критерии задачи корректного размещения адресов информационных источников в едином периодическом ряду команд опроса для бортовой телеметрии с программно управляемым способом сбора. Математическое описание задачи выполнено с использованием аппарата теории чисел, - сравнений. Предлагается и обосновывается дополнительный критерий и графическая модель процесса размещения адресов. Mathematical criteria for the problem of correct placement of information source addresses in a single periodic row of polling commands for onboard telemetry with a program-controlled collection method are considered. The mathematical description of the problem is carried out using the apparatus of number theory - comparisons. An additional criterion and a graphical model of the address allocation process are proposed and substantiated.

Ultrasonic wave has been widely used in the medical field because of its special physical properties. However, it might cause health risk for the human body if the power is inaccurately measured. As a noncontact measurement method, the acousto-optic method gives a lower uncertainty than the mechanical and contact method. To improve the accuracy of ultrasonic power measurement system based on the acousto-optic effect, we optimized the image processing algorithms by adjusting the threshold of binarization, optimizing the centroid coordinates calculation method, and rectangular areas division method. The results showed that the measurement of uncertainty of the acousto-optic method was lower than the radiation balance method, and the accuracy of the measurement system based on the acousto-optic effect was improved from 79.59 to 96.17% after algorithm optimization.

Carbon fiber-reinforced polymer (CFRP) composites are increasingly replacing the metals and other composites in automotive and aerospace industries due to their excellent properties. These application components have required micro-holes on CFRP for joining different components. In the present work, micro-holes are fabricated on CFRP using CO2 laser for achieving the high-quality-dimensional precision and accurate hole. The input parameters such as laser power, cutting velocity and argon pressure were varied. The responses such as heat-affected zone, kerf width, kerf angle and aspect ratio were measured using video measurement system. Besides, analyses of variances, regression modeling and microstructural analysis were presented. Results showed that the cutting velocity is most influential factor that affecting the heat-affected zone and kerf width and followed by power.

Research on cooperation missions of multiple unmanned vehicles (UVs) is growing to overcome the limitations of conventional missions and to increase the variety of missions. In this study, a vision-based recognition and position measurement system was developed to cooperate with an unmanned aerial vehicle (UAV) in case an unmanned ground vehicle (UGV) is unable to drive due to terrain obstacles. Phase, mode, and requirements were derived to develop the vision system. After installing the developed vision system on UAV, several flight tests were conducted, which proved that the system satisfies all requirements. The vision system showed an average measurement error within 1 m for 80 measurements. It is expected that the vision-based system developed in this study can be applied for the cooperative mission of UAVs and UGVs.