No. 1

       Measurement of Physical Quantities

    Pages

Predrag B. Petrović, Maria Vesna Nikolić, Mihajlo Tatović:

New Electronic Interface Circuits for Humidity Measurement Based on the Current Processing Technique

Abstract: 

The paper describes a new electronic conditioning circuit based on the current-processing technique for accurate and reliable humidity measurement, without post-processing requirements. Pseudobrookite nanocrystalline (Fe₂TiO₅) thick film was used as capacitive humidity transducer in the proposed design. The interface integrated circuit was realized in TSMC 0.18 μm CMOS technology, but commercial devices were used for practical realization. The sensing principle of the sensor was obtained by converting the information on environment humidity into a frequency variable square-wave electric current signal. The proposed solution features high linearity, insensitivity to temperature, as well as low power consumption. The sensor has a linear function with relative humidity in the range of Relative Humidity (RH) 30-90 %, error below 1.5 %, and sensitivity 8.3 x 10¹⁴ Hz/F evaluated over the full range of changes. A fast recovery without the need of any refreshing methods was observed with a change in RH. The total power dissipation of readout circuitry was 1 mW.

Baofeng He, D. Patrick Webb, Jon Petzing:

Areal Surface Texture Parameters for Copper/Glass Plating Adhesion Characteristics

Abstract: 

Glass as an alternative printed circuit board material and interposer has been investigated for use in the micro-electronics industry. Electroless copper plating is used to provide the conductive layer, but there is limited understanding of how the surface topography of the glass substrate affects the copper/glass bonding strength exhibited in the current literature. A laser ablation technique was used to prepare glass surfaces with micro-scale structured features in this study, and these features were characterized quantitatively using areal surface texture parameters. The copper/glass bonding adhesion strength was quantified using a scratch testing technique, and the relationships between the critical loads measured and the areal surface parameters, as well as discussion of the underlying mechanisms, are presented in this report. Statistical analysis was employed to identify the most relevant areal parameters that may be used for prediction of the copper/glass bonding strength and for design of adhesion promoting surface textures. The experimental results suggest that the most significant areal surface texture parameters to consider are Sq, Sdq, Sdr, Sxp, Vv, Vmc, and Vvc, and the recommended value range for each parameter for optimal plating adhesion performance is given.

Xiaolei Wang, Huiliang Cao, Yuzhao Jiao, Taishan Lou, Guoqiang Ding, Hongmei Zhao, Xiaomin Duan:

Research on Novel Denoising Method of Variational Mode Decomposition in MEMS Gyroscope

Abstract: 

The noise signal in the gyroscope is divided into four levels: sampling frequency level, device bandwidth frequency level, resonant frequency level, and carrier frequency level. In this paper, the signal in the dual-mass MEMS gyroscope is analyzed. Based on the variational mode decomposition (VMD) algorithm, a novel dual-mass MEMS gyroscope noise reduction method is proposed. The VMD method with different four-level center frequencies is used to process the original output signal of the MEMS gyroscope, and the results are analyzed by the Allan analysis of variance, which shows that the ARW of the gyroscope is increased from 1.998*10^-1°/√h to 1.552*10^-4°/√h, BS increased from 2.5261°/h to 0.0093°/h.

Yuanlu Li:

Signal Smoothing with Time-Space Fractional Order Model

Abstract: 

The time-space fractional-order model (TSFOM) is a generation of the classical diffusion model which is an excellent smoothing method. In this paper, the fractional-order derivative in the model is found to have good performance for peak-preserving. To check the validity and performance of the model, some noisy signals are smoothed by some commonly used smoothing methods and results are compared with those of the proposed model. The comparison result shows that the proposed method outperforms the classical nonlinear diffusion model and some commonly used smoothing methods.

Peng Chen, Qin Chen, Zhijun Xie, Xiaohui Chen, Shaomei Zhao:

A Frequency-Time Algorithm of Parameter Estimation for Sinusoidal Signal in Noise

Abstract: 

In this paper, a computationally efficient and high precision parameter estimation algorithm with frequency-time combination is proposed to improve the estimation performance for sinusoidal signal in noise, which takes the advantages of frequency- and time-domain algorithms. The noise influence is suppressed through spectrum analysis to get coarse frequency, and the fine frequency is obtained by de-noising filtering and using linear prediction property. Then, estimation values of the amplitude and initial phase are obtained. The numerical results indicate that the proposed algorithm makes up for the shortcomings of frequency- and time-domain algorithms and improves the anti-interference performance and parameter estimation accuracy for sinusoidal signal.

Petr Skočík, Martin Pospíšilík, Vojtěch Křesálek, Milan Adámek:

Indirect Measurement of Shielding Effectiveness of an Enclosure for a Security Camera

Abstract: 

This paper presents the results of our experiment, which consisted in measurement of the shielding effectiveness of a camera enclosure that was designed and constructed in order to increase the susceptibility of a camera against external electromagnetic fields. All activities, from defining of requirements to final design and measurements, were performed in the Laboratory of Electromagnetic Compatibility at the Faculty of Applied Informatics of Tomas Bata University in Zlín. The hereby described approach allowed to utilize standardized laboratory equipment that is normally used for device susceptibility test to radiated electric field. The measurement was made inside a semi-anechoic room additionally damped by absorbers placed on its floor. When configuring the experiment, relevant EMC standards EN 55016 and EN 61000-4-3 were considered. Although the uncertainty tolerances, allowed by the relevant standards, were quite high for measurements in such rooms, the results obtained by the experiment matched the theoretical expectations quite satisfactorily.

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     Measurement of Physical Quantities

Marek Vagaš, Ján Semjon, Alena Galajdová, Dušan Šimšík, Róbert Rákay,    Patrik Šarga, Martin Višňovský:

Testing of Selected Accuracy Parameters for the Single Axis Positioner at the Automated Workplace

Abstract: 

Although some authors realized various measurement techniques and relevant standards in the experimental verification, the existing contributions still did not mention more complex automated workplaces with industrial robotic arm participation. To solve this, we provide a different view of the interconnection between individual devices (positioner, robot, etc.) controlled by third-party methods (Siemens products). Also, to obtain the necessary effectiveness, we tested and verified selected accuracy parameters for the participating device component (positioner). The proposed work tries to fulfill expectations for a precise welding technology (to ensure simultaneous movements of both the industrial robotic arm and positioner) to achieve higher quality and better productivity, although the components are from different manufacturers.

Boris Širaiy, Vladimir Ilić, Lazar Toskić:

Usability of Wireless ECG Body Sensor for Cardiac Function Monitoring During Field Testing

Abstract: 

Wireless ECG body sensor Savvy is a feasible solution for reliable and accurate long-term heart rhythm monitoring. However, there were no studies dealing with usability of this sensor in field testing. Accordingly, the aim of the study is to evaluate the quality of the ECG signal measured with wearable wireless ECG body sensor when used in field test settings and to determine how different types of sensor fixation affects the quality of the ECG signal during sub-maximal and maximal running settings. Twenty-three participants, 10 females and 13 males, were included in the study (20.56 ± 1.19 years). All subjects performed shuttle run (SR), Cooper 2400 m (C), and 100 m sprint test (S), once wearing the sensor attached to self-adhesive skin electrodes, additionally fixed with self-adhesive tapes, and secondly with the sensor attached to Polar belt and strapped around the chest. Test outcomes were compared applying the Student t-test for dependent variables, or the non-parametric Wilcoxon test, depending on the results of the normality test. The results showed a significant difference (p<0.05) in the running speed that provides an assessable ECG signal between two different types of fixation in all three running tests – C, S, SR, as well as between the parameters “QRS detected as negative”, “correct software detection”, and “detected QRS” in the C and SR tests. Findings obtained in this study proved that if properly fixed, the ECG signal recorded with wireless ECG can be efficiently used for heart monitoring during physical activities in real setting and potentially could be used as additional tool in detection of cardiovascular diseases. In addition, fixation with Polar belt is more adequate for measurements made during physical activity in real setting compared to fixation with tape.

Erhan Tiryaki, Özlem Kocahan, Serhat Özder:

An Improved Method for Determination of Refractive Index of Dielectric Films from Reflectance Spectrum by Using the Generalized Morse Wavelet

Abstract: 

The Generalized Morse Wavelet (GMW) algorithm was adapted to determine the refractive index of dielectric film from the reflectance spectrum. A theoretically generated reflectance spectrum in the range of 300-1200 nm wavelength was analyzed by the Continuous Wavelet Transform (CWT) and the refractive index dispersion was obtained by the mentioned method. In addition, a noisy reflectance spectrum was analyzed to show the advantages of the CWT method. Refractive index dispersions calculated by the Morlet and the Paul wavelet were compared to GMW at the end of the study.

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Measurement of Physical Quantities

Kang Zhang, Xiaorui Niu, Yunjiao Ma, Xiangmin Chen, Lida Liao, Jiateng Wu:

A New Demodulation Method for Mechanical Fault Feature Extraction based on LOD and IEE

Abstract: 

The rolling bearing and gear fault features are generally shown as modulation characteristics of their vibration signals. The empirical envelope (EE) method is an accordingly common demodulation method. However, the EE method has the defects of over- and undershoot, which may lead to demodulation error. According to this, an envelope optimization algorithm -- empirical optimal envelope (EOE) is introduced into the EE method, and an improved empirical envelope (IEE) method is obtained to calculate the instantaneous amplitude and instantaneous frequency of mono-component modulation signal. Furthermore, aiming at the actual measured mechanical vibration signal has multi-component modulation feature, the IEE method is combined with an adaptive signal decomposition method -- local oscillatory characteristic decomposition (LOD) proposed by the author, thereby a new multi-component signal demodulation method based on LOD and IEE is proposed. The proposed method is compared with Hilbert transform (HT) and Teager energy operator (TEO) demodulation methods by the simulation signal and actual measured mechanical vibration signal. The results show that the demodulation effects including edge effects, negative frequency, over- and undershoot of the proposed method are significantly improved and can extract the rolling bearing and gear fault feature information clearly.

Baofa Hu, Zhiwei Li, Yuanjie Wan, Peng Zhou, Chunquan Zhang, Haisheng San:

3D Printed Pressure Sensor Based on Surface Acoustic Wave Resonator

Abstract: 

This paper reports a 3-dimentional (3D) pressure sensor based on surface acoustic wave (SAW) resonators. The SAW resonators were designed and fabricated on 128°Y-X LiNbO₃ substrate using the MEMS technology. The pressure sensing structure was 3D-printed using polyactic acid plastic, and two SAW resonators were integrated in the 3D-printed chamber structure for both temperature and pressure sensing. The SAW-based gas pressure sensors demonstrate a sensitivity of 589 ppm/MPa at the pressure range of 100-600 kPa and temperature of 40 °C.  

Mochao Pei, Hongru Li, He Yu:

Degradation State Identification for Hydraulic Pumps Based on Multi-scale Ternary Dynamic Analysis, NSGA-II and SVM

Abstract: 

This pap

Degradation state identification for hydraulic pumps is crucial to ensure system performance. As an important step, feature extraction has always been challenging. The non-stationary and non-Gaussian characteristics of the vibration signal are likely to weaken the performance of traditional features. In this paper, an efficient feature extraction algorithm named multi-scale ternary dynamic analysis (MTDA) is proposed. MTDA reconstructs the phase space based on the given signal and converts each embedding vector into a ternary pattern independently, which enhances its capacity of describing the details of non-stationary signals. State entropy (SE) and state transition entropy (STE) are calculated to estimate the dynamical changes and complexity of each signal sample. The excellent performance of SE and STE in detecting frequency changes, amplitude changes, and the development process of fault is verified with the use of four simulated signals. The proposed multi-scale analysis enables them to provide a more precise estimation of entropy. Furthermore, support vector machine (SVM) and nondominated sorting genetic algorithm II (NSGA-II) are introduced to conduct feature selection and state identification. NSGA-II and SVM can conduct the joint optimization of these two goals. The details of the method proposed in this paper are tested using simulated signals and experimental data, and some studies related to the fault diagnosis of rotating machinery are compared with our method. All the results show that our proposed method has better performance, which obtains higher recognition accuracy and lower feature set dimension.

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Measurement of Physical Quantities

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Measurement of Physical Quantities

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Measurement of Physical Quantities

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