Zeitschriftenartikel: „Vibrations measurement“

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Marková, Iveta, und Marek Suchoň. „Evaluation and Measurement of Hand-Transmitted Vibrations“. TRANSACTIONS of the VŠB – Technical University of Ostrava, Safety Engineering Series 12, Nr. 2 (01.09.2017): 66–72. http://dx.doi.org/10.1515/tvsbses-2017-0016.

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Abstract The goal of this work is the effect of vibrations on selected professionals through questionnaire survey and implementation of experimental vibration measurements on a hand of employee. The observation of vibration effects was chosen in a company, where products are being shaped with pneumatic instruments and there is a risk of an exposure of vibrations on the employees. In experimental part are described and evaluated questionnaire surveys conducted on selected risk factors. The reason is the realization of work with vibrating tools for a longer time, where some parts do wear-out and therefore there is a higher exposure to oscillation.

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Frank, DeBord, Hennessy William und McDonald Joseph. „Measurement and Analysis of Shipboard Vibrations“. Marine Technology and SNAME News 35, Nr. 01 (01.01.1998): 1–9. http://dx.doi.org/10.5957/mt1.1998.35.1.1.

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Excessive shipboard vibrations can cause structural and machinery failures, crew discomfort and fatigue, and increased maintenance requirements for shipboard systems. In many cases ship construction specifications require the shipyard to demonstrate "acceptable " levels of vibration using measurements completed during sea trials. This paper provides an overview of standards for these measurements and modern techniques used to collect and analyze the specified vibration data. A brief discussion of the types of vibrations found on ships and their causes is followed by a review of codes, guides and standards for vibration measurement. Instrumentation suitable for measurement of each type of vibration response is described and the design of a typical trial measurement system is presented. Techniques for analyzing and presenting trial results are reviewed and compared with analysis methods specified by SNAME, ISO and NAVSEA. Finally, a discussion of potential problems faced by an owner and shipyard in developing and meeting a vibration measurement specification is offered.

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Kurnatowski, Marek. „Test of Vibrations Influence on the Measurement Accuracy in the Precise Digital Leveller Trimble Dini 03 and Comparison of Its Vibration Sensitivity with Leveller Ni 002“. Civil and Environmental Engineering Reports 30, Nr. 4 (01.12.2020): 111–24. http://dx.doi.org/10.2478/ceer-2020-0054.

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Abstract The article presents findings from research on the effect of vibrations on the accuracy of measurement with an automatic precise digital leveller. A special research station was created to induce vibrations on a leveller and to measure vibration parameters that affect staff reading. It contains description of discovered relationship between the vibration parameters and the mean error of a single height difference measurement. The range of frequencies for which the measurement was possible was estimated. The reliability of the measured values obtained under specific vibration conditions was also analysed. The results of current research were compared with similar studies on analogue leveller Ni 002. The conclusions described in this paper can be helpful in engineering measurements under adverse conditions of ambient vibrations.

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CHANG, HUNG-CHIH, LASZLO B. KISH, ANDREA SZ KISHNÉ, CRISTINE L. S. MORGAN und CHIMAN KWAN. „THEORY AND TECHNIQUES FOR VIBRATION-INDUCED CONDUCTIVITY FLUCTUATION TESTING OF SOILS“. Fluctuation and Noise Letters 08, Nr. 02 (Juni 2008): L125—L140. http://dx.doi.org/10.1142/s021947750800443x.

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First we present and theoretically analyze the phenomenological physical picture behind Vibration-Induced Conductivity Fluctuations. We identify the relevant tensors characterizing the electromechanical response against the vibrations for both longitudinal and transversal responses. We analyze the conductivity response with acceleration type vibrations and a new scheme, measurements with more advantageous compression type vibrations that are first introduced here. Compression vibrations provide sideband spectral lines shifted by the frequency of the vibration instead of its second harmonics; moreover the application of this method is less problematic with loose electrodes. Concerning geometry and electrodes, the large measurement errors in earlier experiment indicated electrode effects which justify using four-electrode type measurements. We propose and analyze new arrangements for the longitudinal and transversal measurements with both compression vibration and acceleration vibration for laboratory and field conditions.

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Murthy, Perunalla PBGSN, Ch Srinivasa Rao und K. Venkata Rao. „Tool and work piece vibrations measurement - a review“. Independent Journal of Management & Production 9, Nr. 4 (01.12.2018): 1254. http://dx.doi.org/10.14807/ijmp.v9i4.801.

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Tool condition monitoring is one of the important aspects in machining process to improve tool life. It comprises three important steps namely machining data acquisition, data analysis and decision making. Vibration in metal cutting has direct impact on the tool life as well as surface roughness. The present study focused on measurement of vibration during the machining process. Data acquisition is made by using various types of sensors. A wide variety of technologies like contact and non contact sensors have been used for real time data acquisition of tool or work piece vibrations. Research works carried out by many authors is highlighted in measurement of cutting tool and machine tool vibrations using different sensors. Influence of various input parameters like tool geometry, feed, speed and depth of cut on the magnitude of vibrations is discussed. Influence of vibration on surface roughness, tool life and power consumption is reviewed. Three dimensional vibration measurement with single Laser Doppler Vibrometer is also covered for precise analysis of vibration.

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Barros, Everaldo de, Carlos d'Andrade Souto, Leandro Ribeiro de Camargo und Mauro Hugo Mathias. „Application of a computer sound card for measurement of mechanical vibrations“. Revista Brasileira de Ensino de Física 37, Nr. 4 (Dezember 2015): 4313–1. http://dx.doi.org/10.1590/s1806-11173742036.

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This paper presents a data acquisition and analysis system based on a computer sound card for measuring and processing random vibration signals. This system turns the computer into a two-channel measurement instrument which provides sample rate, simultaneous sampling, frequency range, filters and others essential capabilities required to perform random vibrations measurements. An easy-to-use software was developed for vibration monitoring and analysis, including facilities for data recording, digital signal processing and real time spectrum analyzer. Since the tasks of vibration data acquisition frequently require expensive hardware and software, this versatile system provides students a very accurate and inexpensive solution for experimental studying mechanical vibrations.

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Mrozek, Piotr, Ewa Mrozek und Andrzej Werner. „Electronic Speckle Pattern Interferometry for Vibrational Analysis of Cutting Tools“. Acta Mechanica et Automatica 12, Nr. 2 (01.06.2018): 135–40. http://dx.doi.org/10.2478/ama-2018-0021.

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Abstract A Michelson interferometer based ESPI system for static and vibration out of plane displacement measurements is presented. The aim of the article is to demonstrate the usability of ESPI non-contact measurement method in the field of machining. The correlation fringe patterns were visualized using custom software. The accuracy of ESPI interferometer was verified by the comparison with measurement results collected using industrial XL-80 laser system. The efficacy in vibration analysis was tested by studying the mode shapes and resonant frequencies of the transverse vibrations of square plates. The measurement methodology was used to determine natural frequencies and the shapes of vibrational modes of NFTe 100x1.2/64-II circular slitting saw. As a result the values of rotational speed that should be avoided during machining were determined.

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Rothberg, S. J., und N. A. Halliwell. „Vibration Measurements on Rotating Machinery Using Laser Doppler Velocimetry“. Journal of Vibration and Acoustics 116, Nr. 3 (01.07.1994): 326–31. http://dx.doi.org/10.1115/1.2930432.

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This paper explores the use of laser vibrometry for vibration measurement directly from a rotating component. The presence of a surface velocity component due to the rotation itself is shown to create a strong measurement dependency on vibration perpendicular to the intended measurement direction. Particular ambiguity results at synchronous frequencies. A mathematical means to resolve the genuine vibration components from two simultaneous laser vibrometer measurements is presented and shown to be effective in the study of nonsynchronous rotor vibrations.

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Seong, Daewoon, Jaehwan Kwon, Deokmin Jeon, Ruchire Eranga Wijesinghe, Jaeyul Lee, Naresh Kumar Ravichandran, Sangyeob Han et al. „In Situ Characterization of Micro-Vibration in Natural Latex Membrane Resembling Tympanic Membrane Functionally Using Optical Doppler Tomography“. Sensors 20, Nr. 1 (20.12.2019): 64. http://dx.doi.org/10.3390/s20010064.

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Non-invasive characterization of micro-vibrations in the tympanic membrane (TM) excited by external sound waves is considered as a promising and essential diagnosis in modern otolaryngology. To verify the possibility of measuring and discriminating the vibrating pattern of TM, here we describe a micro-vibration measurement method of latex membrane resembling the TM. The measurements are obtained with an externally generated audio stimuli of 2.0, 2.2, 2.8, 3.1 and 3.2 kHz, and their respective vibrations based tomographic, volumetric and quantitative evaluations were acquired using optical Doppler tomography (ODT). The micro oscillations and structural changes which occurred due to diverse frequencies are measured with sufficient accuracy using a highly sensitive ODT system implied phase subtraction method. The obtained results demonstrated the capability of measuring and analyzing the complex varying micro-vibration of the membrane according to implied sound frequency.

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Kapustin, V. V., M. L. Vladov, V. A. Volkov und E. A. Voznesensky. „METHODIC ISSUES OF VIBRATIONS MEASUREMENTS FOR EVALUATION OF THEIR IMPACT ON SOIL MASSIFS“. Gruntovedenie 1, Nr. 16 (Januar 2021): 65–77. http://dx.doi.org/10.53278/2306-9139-2021-1-16-65-77.

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The paper is aimed at the attraction of attention of geologists, project engineers and those who operate engineering structures to the necessity of considering real parameters of technical vibrations from various sources in evaluation of the existing and designed soil bases as well as in methodic questions of these parameters’ measurements. In this connection the paper discusses present state of knowledge in measurement and evaluation of vibrations impact on natural and artificial soil massifs along with a brief presentation of theoretical basis of modern vibrometry. It also presents a variant of vibrations classification and discusses engineering geological and geophysical research methods for evaluation of soil behaviour under the influence of vibrations. Information from such studies is analyzed on the example of vibration loads from railway. In conclusions the paper also mentions some important issues of standards for vibration measurements development.

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Tanaka, Kazuhide, Dan Nakaya, Yuki Kondo und Ichiro Yoshida. „A Study on Optimal Voltage of Electromagnet for Precision Measuring Robot During Surface Roughness Measurement by Vibration Analysis“. International Journal of Automation Technology 15, Nr. 4 (05.07.2021): 537–45. http://dx.doi.org/10.20965/ijat.2021.p0537.

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In electric power stations, precision surface roughness measurements are performed for environmental loading reduction, quality assurance, and safety. These measurements are performed manually at high places, narrow places, uncomfortable environments, etc. Therefore, workers in power stations experience a lot of hardship and are exposed to danger. To solve these issues, this study researched and developed a crawler-type robot with high measurement accuracy. Conventionally, robots that supply workpieces for surface roughness instruments have been developed. However, to the best of our knowledge, robotization and self-propelled precision measurement instruments have not been developed. Usually, a precision measurement instrument is designed for increased stiffness and stability because high measurement accuracy is the highest priority. However, if the stiffness and stability of the robot are as high as those of the precision measurement instrument, a problem occurs in the robot operation. Therefore, we propose a precision measurement unit using electromagnets and a crawler-type self-propelled robot to equip the unit. In a previous study, vibration analysis experiments using the impulse response method were performed on a precision measuring robot. In this study, the relationships between the voltages applied to the electromagnet and the reductions in the vibration magnitudes were determined by analyzing the vibrations of the robot during measurement. Furthermore, an optimal voltage of the electromagnets of the precision measuring robot to reduce vibrations was determined. From the results of the vibration analysis, the authors demonstrated that the optimal voltages were 9 and 12 V, and the precision measurement unit confirmed the effectiveness and validity of vibration reduction and improved measurement accuracy.

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Kilikevičius, Artūras, Vladas Vekteris und Albinas Kasparaitis. „Precision Measurement of the Carriage Vibrations at the Different Speeds“. Solid State Phenomena 147-149 (Januar 2009): 690–95. http://dx.doi.org/10.4028/www.scientific.net/ssp.147-149.690.

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Dependence of a comparator reading dynamic error on vibro activity of a carriage is analyzed in the paper. There is shown how change reading errors at action only carriage drive vibrations and at artificially provoked carriage vibrations at different frequencies. Results achieved enable to evaluate the influence of vibration components on reading errors.

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Hornik, Beata, Jan Duława, Czesław Marcisz, Wojciech Korchut und Jacek Durmała. „The Effect of Mechanically-Generated Vibrations on the Efficacy of Hemodialysis; Assessment of Patients’ Safety: Preliminary Reports“. International Journal of Environmental Research and Public Health 16, Nr. 4 (18.02.2019): 594. http://dx.doi.org/10.3390/ijerph16040594.

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Muscle activity during a hemodialysis procedure improves its efficacy. We have formulated a hypothesis that vibrations generated by a specially-designed dialysis chair can, the same as physical exercise, affect the filtering of various fluids between fluid spaces during the hemodialysis procedure. This prospective and interventional study included 21 dialyzed patients. During a single dialysis session, each patient used a prototype device with the working name “vibrating chair”. The chair’s drive used a low-power cage induction motor, which, along with the worm gear motor, was a part of the low-frequency (3.14 Hz) vibration-generating assembly with an amplitude of 4 mm. Tests and measurements were performed before and after the vibration dialysis. After a single hemodialysis session including five 3-min cycles of vibrations, an increase in K t / V in relation to non-vibration K t / V ( 1.53 ± 0.26 vs. 1.62 ± 0.23 ) was seen. Urea reduction ratio increased significantly ( 0.73 ± 0.03 vs. 0.75 ± 0.03 ). A significant increase in systolic blood pressure was observed between the first and the third measurement ( 146 ± 18 vs. 156 ± 24 ). The use of a chair generating low-frequency vibrations increased dialysis adequacy; furthermore, it seems an acceptable and safe alternative to intradialytic exercise.

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Xu, Zhaogang, Yu Lou und Liu Chen. „Vibration Measurement and Prediction for Foundation Slab Design of a High-Tech Lab Based on In Situ Testing“. Shock and Vibration 2020 (28.10.2020): 1–12. http://dx.doi.org/10.1155/2020/8892597.

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Reduction of road traffic-induced vibrations has gained importance with rapid development of high-tech industry and nanotechnology. This study focuses on the in situ vibration measurement and transmissibility-based vibration prediction for the foundation slab design of a high-tech lab subjected to truck-induced vibrations. The truck-induced vibrations come from a proposed road 30 m away from the high-tech lab. The allowable vertical vibration velocity for the foundation slab of the high-tech lab was 60 μm/s in the frequency range of 5–50 Hz. The truck-induced ground vibrations in the proximity of an existing road with the same design as the proposed road were taken as the vibration source response used in the foundation design. The ground vibration transmissibility from the proposed road area to the high-tech lab area was determined by conducting frequency sweep tests in the free field. Based on the vibration source response and the ground vibration transmissibility, two antivibration foundation prototypes with different thicknesses were constructed at the site. The vibration transmissibility from the subgrade soil to the surfaces of the two foundation prototypes was obtained by measuring the ground vibrations at the high-tech lab area and the surface vibrations of the two foundation prototypes. The vertical vibration velocities of the two foundation prototypes were predicted based on the measured transmissibility and the vibration source response. The final thickness of the antivibration foundation was determined by comparing the predicted vibration velocities with the allowable vibration velocity. After construction of the high-tech lab and the road, vibration tests were conducted to assess the performance of the actual antivibration foundation. The results showed that the actual antivibration foundation was able to reduce the vibration levels at the high-tech lab to acceptable levels.

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Grzesica, Dariusz. „Measurement and analysis of truck vibrations during off-road transportation“. MATEC Web of Conferences 211 (2018): 13003. http://dx.doi.org/10.1051/matecconf/201821113003.

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Measurement of vibration of the vehicle on the road surface is one of the key elements of cargo and vehicle security. This paper provides results from transporting military cargo study that analyzed the various vibrations of acceleration during transport on a stony pavement road. The data include vibrations from three directions: longitudinal, transverse and vertical. Based on collected data the quantitative analysis of vibrations was conducted. The peak acceleration as well as the acceleration level was identified. The growth rate acceleration affecting the smoothness of driving and the impact of the vehicle on the stony surface were calculated. The study shows that the greatest impact on transporting cargo have vertical vibrations. In addition, using the Fourier transform, amplitude spectrum for all directions of oscillation was assigned.

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Kożuch, Barbara, Filip Pachla und Tadeusz Tatara. „Vibrations induced by the passage of trains at various speeds and their effect on the structural response of buildings - an experimental and numerical analysis“. MATEC Web of Conferences 211 (2018): 13007. http://dx.doi.org/10.1051/matecconf/201821113007.

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This paper presents a selection of vibration measurement results and analyses performed with regard to their harmfulness to residential buildings. The first part of the paper refers to the analysis of railway vibrations measured in situ at the foundation level of residential building. These vibration records were then used to assess the harmfulness of vibrations relating to each train speed. Assessment of the vibration harmfulness of the building was performed with an indicator of the perceptibility of vibration through a structure (WODB), according to the Polish standard. The second part of the study refers to the creation of dynamic models of buildings with the use of the ‘Diana’ software program and analysis of their responses to railway vibrations. The thresholds specified by the standard in any of the train speeds of up to 250 km/h were not exceeded. Nevertheless, propagation of vibrations induced by train passages and their effect on the structural response of buildings is a complex phenomenon. Without in situ measurements, it is hard to assess the impact of induced vibrations on buildings. As proven in the paper, a train moving on a track at various speeds does not uniformly make the vibration greater in each frequency band.

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Rodriguez, Cristian G., Borja Mateos-Prieto und Eduard Egusquiza. „Monitoring of Rotor-Stator Interaction in Pump-Turbine Using Vibrations Measured with On-Board Sensors Rotating with Shaft“. Shock and Vibration 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/276796.

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Current trends in design of pump-turbines have led into higher rotor-stator interaction (RSI) loads over impeller-runner. These dynamic loads are of special interest having produced catastrophic failures in pump-turbines. Determining RSI characteristics facilitates the proposal of actions that will prevent these failures. Pressure measurements all around the perimeter of the impeller-runner are appropriate to monitor and detect RSI characteristics. Unfortunately most installed pump-turbines are not manufactured with in-built pressure sensors in appropriate positions to monitor RSI. For this reason, vibration measurements are the preferred method to monitor RSI in industry. Usually vibrations are measured in two perpendicular radial directions in bearings where valuable information could be lost due to bearing response. In this work, in order to avoid the effect of bearing response on measurement, two vibration sensors are installed rotating with the shaft. The RSI characteristics obtained with pressure measurements were compared to those determined using vibration measurements. The RSI characteristics obtained with pressure measurements were also determined using vibrations measured rotating with shaft. These RSI characteristics were not possible to be determined using the vibrations measured in guide bearing. Finally, it is recommended to measure vibrations rotating with shaft to detect RSI characteristics in installed pump-turbines as a more practical and reliable method to monitor RSI characteristics.

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Koleva, M., und K. Mladenov. „Measurement and Analysis of Railway Noise and Vibration“. Noise & Vibration Worldwide 31, Nr. 5 (Mai 2000): 8–12. http://dx.doi.org/10.1260/0957456001497580.

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The acoustic environment, as well as the length and speed of the train, determine noise and vibration levels. The average intensity of the noise (assessing by SEL) varies from 83.9 to 104.1 dB/A: the highest intensity accompanies the passing of express (average 95.32 dB/A); the lowest intensity is measured during the passing of EMU (average 89.24 dB/A). Vibrations of the highest intensity are measured during the passing through free fields (0.750 mm.sec−1). Regardless of the bridge type, the level of vibrations varies between 0.032 – 0.067 mm.sec−1.

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Chen, GX, S. Zhang, BW Wu, XN Zhao, ZF Wen, H. Ouyang und MH Zhu. „Field measurement and model prediction of rail corrugation“. Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 234, Nr. 4 (09.10.2019): 381–92. http://dx.doi.org/10.1177/0954409719877318.

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In a field test, three corrugation profiles of rails and their corresponding vibrations were measured, and the wavelengths and frequencies of rail corrugations were obtained. In the model prediction, finite-element models of the self-excited vibrations corresponding to three different wheelset–track systems were established. The corrugation frequencies of these models were predicted, and a comparison between the measured and the predicted corrugation frequencies showed that they are in good agreement. It can be concluded that the self-excited vibration of a wheelset–track system can cause rail corrugation. A benchmark condition for the validation of rail corrugation models is proposed.

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Nedoma, Jan, Martin Stolarik, Stanislav Kepak, Miroslav Pinka, Radek Martinek, Jaroslav Frnda und Michael Fridrich. „Alternative Approaches to Measurement of Ground Vibrations Due to the Vibratory Roller: A Pilot Study“. Sensors 19, Nr. 24 (09.12.2019): 5420. http://dx.doi.org/10.3390/s19245420.

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At present, one of the primary tasks of the construction industry is to build transport infrastructure. This concerns both the construction of new bypasses of towns and the repair of existing roads, which are damaged by congestion, especially by freight transport. Whether it is a new building or a reconstruction, it is always very important to choose a suitable method of subsoil treatment. One of the most commonly used methods for soil treatment is currently compaction using vibratory rollers. This method is very effective both in terms of results and due to its low financial demands compared to other methods. Vibration is transmitted to the surrounding rock environment when compacting the subsoil using vibratory rollers. Although the intensity of these vibrations is not as pronounced as in other methods of subsoil treatment, such vibrations can have a significant effect, for example during compaction in urban areas or in an area with the presence of historical objects. Therefore, it is very advisable to monitor the effect of these vibrations on the environment during construction. This paper brings an original experimental comparative study of standard seismic instrumentation with a developed interferometric sensor for the field of monitoring vibrations generated during compaction of subsoil using vibrating rollers. The paper presents time and frequency domain results, as well as attenuation curves, which represent real attenuation of vibrations in a given rock environment. The results presented here show that a system operating on a different physical principle from the one used at present has the potential to replace the existing, very expensive, seismic equipment.

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Stanbridge, A. B., und D. J. Ewins. „Measurement of Translational and Angular Vibration Using a Scanning Laser Doppler Vibrometer“. Shock and Vibration 3, Nr. 2 (1996): 141–52. http://dx.doi.org/10.1155/1996/737569.

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An experimental procedure for obtaining angular and translational vibration in one measurement, using a continuously scanning laser Doppler vibrometer, is described. Sinusoidal scanning, in a straight line, enables one angular vibration component to be measured, but by circular scanning, two principal angular vibrations and their directions can be derived directly from the frequency response sidebands. Examples of measurements on a rigid cube are given. Processes of narrow-band random excitation and modal analysis are illustrated with reference to measurements on a freely suspended beam. Sideband frequency response references are obtained by using multiplied excitation force and mirror-drive signals.

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Nguyen, Thanh Q., Thao D. Nguyen, Lam Q. Tran und Nhi K. Ngo. „A New Insight to Vibration Characteristics of Spans under Random Moving Load: Case Study of 38 Bridges in Ho Chi Minh City, Vietnam“. Shock and Vibration 2020 (04.11.2020): 1–20. http://dx.doi.org/10.1155/2020/1547568.

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We propose a novel representative power spectrum density as a specific characteristic for showing responses of spans during a long operational period. The idea behind this method is to use the representative power spectrum density as a powerful tool to evaluate the stiffness decline of spans during their operation period. In addition, a new measurement method has been introduced to replace the traditional method of monitoring the health conditions of bridges through a periodic measurement technique. This helps to reduce costs when carrying out testing bridges. Besides, the proposed approach can be widely applied not only in Vietnam but also in many other underprivileged countries around the world. Obtained results show that, during the operational process of spans, there is not only a pure vibration evaluation such as bending vibration and torsion vibration tests but also a combination of various vibration types including bending-torsion vibration or high-level vibrations like first-mode bending and first-mode torsion. Depending on each type of structure and material properties, different types of vibrations will appear more or less during the operational process of spans under a random moving load. Furthermore, the representative power spectrum density is also suitable for evaluating and determining many different fundamental vibrations through the same measurement time as well as various measurement times.

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Takahashi, Morito, Satoshi Nishimoto, Koh Hashimoto, Yuji Koike, Masao Mutaguchi und Hidesaku Ueshima. „Vibration Control of Hakucho Bridge Tower under Construction Using Actively-Controlled Mass Damper“. Journal of Robotics and Mechatronics 6, Nr. 3 (20.06.1994): 262–65. http://dx.doi.org/10.20965/jrm.1994.p0262.

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Free-standing bridge towers, in general, suffer from vibrations caused by wind. In order to reduce vibrations, an actively-controlled mass damper was applied to Hakucho Bridge tower. In controlling vibrations, the node of the 2nd mode was selected as a settling point of sensors in order to maintain stability for higher order modes of vibration than that to be controlled. The damper was tested to verify damping performance by free vibration and measurement of vibrations caused by wind. High performance has been obtained from results of tests and the effectiveness of this method has been demonstrated.

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Kljuev, Vladimir V., Valery P. Kozlov, Alexandr P. Degterev, Irina A. Vainberg, Vladimir V. Demidov und Anatoly N. Filimonov. „Device for measurement of vibrations“. Journal of the Acoustical Society of America 78, Nr. 2 (August 1985): 821. http://dx.doi.org/10.1121/1.393079.

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Reinhardt, A. K., J. R. Kadambi und R. D. Quinn. „Laser Vibrometry Measurements of Rotating Blade Vibrations“. Journal of Engineering for Gas Turbines and Power 117, Nr. 3 (01.07.1995): 484–88. http://dx.doi.org/10.1115/1.2814121.

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One of the most important design factors in modern turbomachinery is the vibration of turbomachinery blading. There is a need for developing an in-service, noncontacting, noninterfering method for the measurement and monitoring of gas turbine, jet engine, and steam turbine blade vibrations and stresses. Such a technique would also be useful for monitoring rotating helicopter blades. In the power generation industry, blade failures can result in millions of dollars of downtime. The measurement of blade vibrations and dynamic stresses is an important guide for preventive maintenance, which can be a major contributor to the availability of steam turbine, gas turbine, and helicopter operations. An experiment is designed to verify the feasibility of such a vibration monitoring system using the reference beam on-axis laser-Doppler technique. The experimental setup consists of two flat, cantilever blades mounted on a hub attached to the shaft of a dc motor. The motor rests on a linear bearing permitting motion only in the direction of the motor shaft. The motor and blade assembly is then excited via an electrodynamic shaker at the first natural frequency of the blades. The resulting blade vibration is then detected using a laser vibrometer. The vibration frequencies and amplitudes of the two rotating blades are successfully measured.

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Hirao, Yoshihiro. „INCE/J Vibration Measurement Manual for Buildings—Part 3: Measurement example of building vibrations“. Journal of the Acoustical Society of America 140, Nr. 4 (Oktober 2016): 3280. http://dx.doi.org/10.1121/1.4970421.

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Adamczak, Stanisław, Mateusz Wrzochal und Paweł Zmarzły. „Measurement of vibrations occurring in rolling bearings“. Mechanik 90, Nr. 8-9 (11.09.2017): 734–36. http://dx.doi.org/10.17814/mechanik.2017.8-9.107.

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There are three criteria the vibration measurement methods as applied at each stage of the rolling-element bearing life period could be classified to. Analysis of these methods is suggested for better understanding of the rolling bearing operating problems and of the issues related to dynamic measurements.

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Kurnatowski, Marek. „Test of Impact of Vibrations Frequency on Mean Errors of the Precise Height Differences Measurement with Analogue Automatic Leveller Ni002“. Civil and Environmental Engineering Reports 28, Nr. 4 (01.12.2018): 129–37. http://dx.doi.org/10.2478/ceer-2018-0056.

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Abstract The article describes the results of tests carried out to determine the measurable effect of vibrations on the accuracy of measurements with an automatic precise leveller. It contains specification of the research station created to examine the case and description of factors affecting the measurement results. The multi-frequency vibrations were forced on a leveller during measurements and calculated mean errors for each frequency analysed. The range of frequencies for which the measurement was possible was estimated. The obtained results can be helpful in the engineering measurements designing, especially in industrial areas, where vibrations are an inseparable element of the environment.

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Sunar, M., und B. O. Al-Bedoor. „Vibration measurement of a cantilever beam using root embedded piezoceramic sensor“. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 222, Nr. 2 (01.02.2008): 147–61. http://dx.doi.org/10.1243/09544062jmes621.

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Numerical and experimental studies are carried out to investigate the usability of a piezoceramic (PZT) sensor placed in the root of a stationary cantilever beam for measuring structural vibrations. The ability of the sensor for picking up the vibration signals during both the transient and steady-state phases is investigated. The piezoelectric equations obtained using the Hamilton's principle together with the finite-element approximation are utilized to extract the voltage outputs of the PZT sensor. An experimental set-up, to validate the theoretical results, is designed and manufactured. The experimentally measured sensor voltages are compared with the numerical ones. The results showed the excellent performance of the sensors in reading vibration signals of the beam. The root embedded PZT approach is an important step towards the application of measuring rotating blade vibrations.

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Moskovets, Mariya, und Nikolay Kanev. „Assessment of Rail Vibration Transmission from the Ground to the Foundation of a Building“. MATEC Web of Conferences 320 (2020): 00005. http://dx.doi.org/10.1051/matecconf/202032000005.

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This paper presents the problem of rail transport vibration transmission from the ground to building foundations. Field measurement results of vibration parameters on the ground near buildings and their foundations have been covered in this study. It has been shown that vibrations at the foundation of a building are much smaller than vibrations on the ground. The most intense vibrations on the foundation slab occur in the vertical direction. Comparison with other experimental data on vibration transfer from the ground to buildings structures has been made. The data obtained can be utilized in designing vibration protection measures and to analytically predict vibration effects in buildings. This analysis can be performed after measuring the vibration of rail transport on the ground surface.

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Jovanović, Dragan, Milena Jovanović, Miomir Raos, Nenad Živković, Milena Stanković und Milan Protić. „Vibration Analysis of Insufficiently Repaired Well Pump - A Case Study“. Applied Mechanics and Materials 801 (Oktober 2015): 207–12. http://dx.doi.org/10.4028/www.scientific.net/amm.801.207.

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Vibration analysis of the repaired well pump is to determine whether vibrations occur due to an insufficient pump repair or due to some new malfunction that happened after the repair. This paper presents vibration analysis of well pump as well as the applied corrections in order to lower the vibration levels. Vibration measurement of well pump is conducted on measurement points defined by standard ISO 10816-1.

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Merrick, Alan. „Uncharted Waters: Vibration Measurement in Thermal Chambers“. Journal of the IEST 46, Nr. 1 (14.09.2003): 135–40. http://dx.doi.org/10.17764/jiet.46.1.73l46720q1502340.

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Most space flight structures typically are tested for thermal and vacuum survivability, cycled initially at the component level to relieve internal strains and as an end product to verify thermal balance and operation as a complete system. Dynamic testing is generally performed on the individual components and as a complete system prior to the thermal vacuum test. This paper discusses a test requiring vibration data measurement in a thermal environment. Vibrations were induced internally by the thermal cycling of the structure (internal stress relief) as well as input with a shaker system capable of operating at cryogenic (LN2) temperatures. The intent of this vibration input was to characterize the structure rather than performing a qualification vibration environment. Requests for vibration measurements in thermal and vacuum environments are becoming more common, although this is the first test completed at Lockheed Martin Sunnyvale.

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Rossi, G., R. Marsili, V. Gusella und M. Gioffrè. „Comparison between Accelerometer and Laser Vibrometer to Measure Traffic Excited Vibrations on Bridges“. Shock and Vibration 9, Nr. 1-2 (2002): 11–18. http://dx.doi.org/10.1155/2002/968509.

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The use of accelerometer based measurement techniques for evaluating bridge forced vibrations or to perform bridge modal analysis is well established. It is well known to all researchers who have experience in vibration measurements that values of acceleration amplitude can be very low at low frequencies and that a limitation to the use of accelerometer can be due to the threshold parameter of this kind of transducer. Under this conditions the measurement of displacement seems more appropriate. On the other hand laser vibrometer systems detect relative displacements as opposed to the absolute measures of accelerometers. Vibrations have been measured simultaneously by a typical accelerometer for civil structures and by a laser vibrometer equipped with a fringe counter board in terms of velocity and displacements. The accelerations calculated from the laser vibrometer signals and the one directly measured by the accelerometer has been compared.

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Nava, P., N. Paone, G. L. Rossi und E. P. Tomasini. „Design and Experimental Characterization of a Nonintrusive Measurement System of Rotating Blade Vibration“. Journal of Engineering for Gas Turbines and Power 116, Nr. 3 (01.07.1994): 657–62. http://dx.doi.org/10.1115/1.2906870.

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A measurement system for nonintrusive monitoring of rotating blade vibration in turbomachines based on fiber optic sensors is presented. The design of the whole system is discussed; the development of special purpose sensors, their interfacing to the data acquisition system, and the signal processing are outlined. The processing algorithms are tested by software simulation for several possible blade vibrations. Experimental tests performed on different bladed rotors are presented. Results are compared to simultaneous strain gage measurements.

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Menh, Nguyen Cao, und Tran Trong Toan. „Determination of beam characteristics by its vibration measurement“. Vietnam Journal of Mechanics 17, Nr. 3 (30.09.1995): 27–38. http://dx.doi.org/10.15625/0866-7136/10136.

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On the basis of analyzing the transverse vibration of a clamped-free beam, in this paper an inverse problem is investigated. The analytical method· and computational program me have been presented for determination of the length of the beam when vibrations at some points on the beam with external distribution excitation or vibration at one point with some excited frequencies are measured. The obtained results from the illustration examples described in the paper give us the procedure for selecting one solution in multi-solution inverse problem.

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Kiełbasa, Paweł, Tomasz Dróżdż und Dominika Wojtas. „Analysis of general and local vibration at the workplace: the operator of a specialist road machine“. AUTOBUSY – Technika, Eksploatacja, Systemy Transportowe 20, Nr. 1-2 (28.02.2019): 281–86. http://dx.doi.org/10.24136/atest.2019.051.

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The article discusses an attempt to evaluate the ergonomic vibration environment of selected technical sources used in various technological processes. The scope of the tests included measurement of general vibrations in the plane of the seat carrier and local vibrations occurring on the steering wheel of selected technical sources. The tests were carried out in two trucks and in a vibratory road roller. The measurements were carried out in 10 repetitions for each technical measure. On the basis of the obtained measurements, the mean value of vibration acceleration, effective vibration acceleration and peak vibration acceleration as well as the weighted vibration acceleration value were determined. The obtained results were confronted with the applicable standards. It was noted that the daily vibration exposure of general action in the case of road roll works in the horizontal direction was 1,11 m∙s-2 and exceeded the limit values for men and women in the working age. In the case of other vehicles tested, there was no exceedance of the permissible mechanical vibration value in any of the analyzed directions and do not pose a threat to the employee.

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Abramov, O. A., V. V. Emelyanov, O. G. Kutsenko, G. K. Otto, K. V. Otto und L. K. Yarovoi. „Laser doppler vibrometer with remote object scanning capability“. Bulletin of Taras Shevchenko National University of Kyiv. Series: Physics and Mathematics, Nr. 1 (2019): 16–19. http://dx.doi.org/10.17721/1812-5409.2019/1.2.

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A laser Doppler vibrometer was created with the ability to measure the vibrations of distant objects up to 250 meters away. The vibrometer is provided with a scanning system for automatic vibration measurement in an array of points. The control program moves the probe beam according to the research protocol, processes and store information. To demonstrate the capabilities of the system, we studied of the amplitude distribution of vibrations and the distribution of longitudinal stresses in a cantilevered tube located at a distance of 22 meters. The measurements at different frequencies are in good agreement with the numerical calculations performed by finite element code CalculiX.

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Choi, Y. H., S. M. Cha, J. H. Hong und Jai Hyuk Choi. „A Study on the Vibration Analysis of a Ball Screw Feed Drive System“. Materials Science Forum 471-472 (Dezember 2004): 149–54. http://dx.doi.org/10.4028/www.scientific.net/msf.471-472.149.

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Feed drive system of machine tools may experience serious vibrations or unstable motions during high-speed operation. In this paper, a 6 D.O.F (Degree-Of-Freedom) lumped parameter model was proposed in order to analyze vibrations of a ball screw feed-drive system, which takes planar motion. The equations of motion were derived for the proposed model. Natural frequencies of the system and transient responses due to driving motor speed control input were also analyzed. Experimental modal analysis and operational vibration measurements of a laboratory ball screw feed drive system were made. Both theoretical analysis and experimental measurement results showed good agreement with each other. Consequently we concluded that the proposed 6 D.O.F model could be well applicable to the vibration analysis of a ball screw feed-drive system.

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Czopek, Dorota, Robert Barański und Jerzy Wiciak. „Module for Monitoring the Probe-Skin Contact Force in the Study of Vibration Perception on the Wrist“. Sensors 21, Nr. 6 (18.03.2021): 2128. http://dx.doi.org/10.3390/s21062128.

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This paper presents a module for monitoring the contact force between a probe for measuring vibration perception on the wrist and the skin. The module was designed for an original measuring stand for the automatic testing of the vibrotactile discrimination thresholds using the psychophysical adaptive method of 1 up–2 down with two or three interval forced choices (2IFC, 3IFC). Measurement methods were implemented in LabVIEW software. The inspiration for the project was the need to check the possibility of building a vibrating interface for transmitting information through vibrations delivered to the wrist via a bracelet. The test procedure on the wrist is not standardized; however, during its development, the recommendations of the Polish Norm–International Organization for Standardization PN-ISO 13091-1, 2006 were adopted. This standard contains methods for measuring vibration sensation thresholds on the fingertips for the assessment of neural dysfunction. The key to the repeatability of measurements seems to be the ability to continuously control the pressure of the measuring probe on the skin. This article compares two solutions for measuring the contact force along with an analysis of their accuracy and the impact of vibrations on the measured values. Moreover, the results of measurements of vibrotactile amplitude and frequency discrimination thresholds obtained on the ventral wrist at five frequencies (25, 32, 63, 125 and 250 Hz) are presented.

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Liebold, Florian, Stephan Wiegand und Ronny Käso. „Reaction Wheel Disturbance Characterization by Analysis of Micro-Vibration Measurements“. Applied Mechanics and Materials 232 (November 2012): 445–49. http://dx.doi.org/10.4028/www.scientific.net/amm.232.445.

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Structural stability of satellites is of vital significance for the operation of sophisticated payload systems. Therefore manufacturers of satellite components, such as reaction wheels, make huge efforts to assure the convenient vibration behavior of their products. To meet that demand a device for the detection of mechanical oscillations with very small amplitudes was developed. The described micro-vibration test-bench allows the detection of vibrations with amplitudes > 10 5 Newton in a frequency range of < 20 kHz generated by a test item with a mass up to 30 kg. The quality of the thereby obtained data makes it possible to identify the sources of the observed vibration. The high information content of the measurements originates from a set of high resolution force sensors, variably arranged on a mechanically isolated platform. The sensitivity of the used equipment (charge cables, charge amplifiers and signal analyzers) and its resistance to ambient disturbances allow the high accuracy of the measurement as mentioned above. The described micro-vibration test-bench additionally provides opportunity to detect production errors non-destructively and helps to reduce the inherent noise of the item under test. It therefore represents a reliable measurement device to quantify and assess detrimental vibrations.

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Wu, Bin-Yi, Xian-Sheng Qin, Shun-Qi Zhang, Jing Bai, Ting Xue und Rüdiger Schmidt. „Unknown disturbance estimation for vibration systems using distributed piezoelectric sensors“. Mechanics & Industry 19, Nr. 5 (2018): 506. http://dx.doi.org/10.1051/meca/2018042.

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Vibration is usually caused by external disturbances, which may lead to structural damage. Vibrations can be significantly suppressed by taking disturbances into account. However, in many cases disturbances are unknown or difficult to be measured directly. In order to estimate external unknown disturbances, this article develops a proportional-integral (PI) disturbance observer with measurement noises for smart structures using multiple distributed piezoelectric sensors. For simulation purpose, a dynamic finite element model of piezoelectric bonded smart structure is presented. This disturbance observation method is validated by estimating various kinds of unknown disturbances using piezoelectric measurements. Furthermore, the measurement numbers and the position of measurements are investigated.

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Golubkov, V. A., V. F. Shishlakov, A. G. Fedorenko und E. Yu Vataeva. „ACCURACY RATING MEASUREMENT OF VIBRATION ELECTROMECHANICAL DEVICES“. Issues of radio electronics 1, Nr. 7 (11.07.2019): 42–45. http://dx.doi.org/10.21778/2218-5453-2019-7-42-45.

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Electromechanical devices consist mainly of rotor systems. Vibration is the result of the interaction of the elements of the rotor system and is largely determined by the accuracy of manufacturing elements at the production stage and defects arising in the process of operation. The main components of the rotor systems that affect vibration are bearings. To determine the technical condition of the bearings and the service life of the rotor system, it is necessary to accurately measure the unobservable vibrations of the rotor. The article describes the model of the channel for measuring the vibration of an electromechanical system, built using the apparatus of bond graphs. The transfer function is obtained by analyzing the signal flow graph. The systematic and random errors of vibration measurement are analyzed depending on the mass ratio between the system case and the vibration transducer for various sensor masses and attachment rigidity.

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Jogi, Pushkar N., John D. Macpherson und Michael Neubert. „Field Verification of Model-Derived Natural Frequencies of a Drill String“. Journal of Energy Resources Technology 124, Nr. 3 (06.08.2002): 154–62. http://dx.doi.org/10.1115/1.1486018.

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Vibrations generated in a drill string while drilling generally lead to a reduction in drilling efficiency and often cause premature failure of drill string components and bit damage. It is also known that lateral vibrations, in particular, are responsible for most measurement-while-drilling (MWD) tool failures while drilling. One way to increase drilling efficiency and avoid tool damage is to monitor and analyze drilling vibrations so that drilling parameters can be adjusted while drilling to reduce such vibrations. An alternative method is to analyze and determine the natural frequencies of the bottom-hole assembly (BHA) so that resonant conditions caused by various excitation mechanisms in the drill string can be avoided. Even though models have been developed in the past in the drilling industry to determine the natural frequencies of a BHA, few attempts have been made to demonstrate that such models do actually help reduce vibrations or failures. This paper deals with the process of field validation of model-derived frequencies for axial, torsional and lateral vibrations. The results presented in this paper are based on the analysis of drilling data from a field test using downhole vibration measurement sensors. The downhole measurements included X and Y bending moments, axial acceleration, dynamic weight-on-bit, dynamic torque, and X and Y-axis magnetometers mounted in an MWD sub. The data analysis demonstrates that the natural frequencies predicted by the models match well with actual field (measured) values at the locations of interest, particularly for lateral vibrations. This analysis therefore shows that model derived results can be used with a degree of confidence to help avoid resonant conditions in a BHA while drilling and to help reduce failures.

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Sunar, M., und B. O. Al-Bedoor. „Vibration Measurement of Rotating Blades Using a Root Embedded PZT Sensor“. Shock and Vibration 15, Nr. 5 (2008): 517–41. http://dx.doi.org/10.1155/2008/494639.

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Finite element and experimental studies are carried out to test the suitability of a piezoelectric (PZT) sensor in measuring vibrations of blades modeled as beams. The rotating system contains twelve blades mounted to the shaft through a rotor. The PZT sensor is secured in the root between the rotor and blade. First, finite element results are obtained using the finite element package ANSYS. A modal analysis is performed on the system to identify modes and mode shapes. Transient, harmonic and steady-state responses are then computed to test the ability of the PZT sensor in generating signals for blade vibrations. For the experimental part, the blade vibration signals are produced using the PZT sensor and a strain-gage, and the outputs are compared with each other. From both the finite element and experimental results, it is concluded that the root-embedded PZT sensor can be effectively used for blade vibration measurements in a wide range of cases.

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Targosz, Jan, Jarosław Bednarz und Wojciech Lisowski. „Analysis of the Possibility of Limiting the Impact of Ground Vibrations Caused During Demolition of a Towers on Environment“. Archives of Acoustics 41, Nr. 4 (01.12.2016): 649–57. http://dx.doi.org/10.1515/aoa-2016-0062.

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Abstract Before disassemble and demolition of five granulation towers the authors planned and carried out measurements of the intensity of vibrations induced during the fall of the dismantled components of towers on the ground. The main aim of the study was to determine the maximum permissible weight of falling elements of the towers during the demolition, in terms of ensuring the protection of buildings and equipment located in the vicinity of the works. It was unacceptable to increase the vibration amplitude displacement in each section of measurement on each of the three perpendicular axes by more than 2 μm peak-to-peak value and the absolute velocity of RMS of vibration amplitude couldn’t be increased by more than 1 mm/sec value than the background vibration during the demolition of the towers. Preliminary experimental studies were conducted on a test stand and the measurements were made on the real object. The amplitudes of vibration waves displacement and velocity were recorded on the measurement section in the direction of the protected building. The results of measurements were used to identify the propagation of the shock wave and the effectiveness of the proposed insulation layers.

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Tuo, Jiying, Zhaoxiang Deng, Heshan Zhang und Jinshan Qiu. „A 3-axis torsion quasi-zero-stiffness-based sensor system for angular vibration measurement“. Journal of Vibration and Control 24, Nr. 18 (01.08.2017): 4325–36. http://dx.doi.org/10.1177/1077546317724016.

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In this paper, a novel 3-axis torsion quasi-zero-stiffness (TQZS)-based sensor system is proposed for absolute rotation measurement in vibration systems. Analysis on the applied torque and structural parameters shows that the proposed mechanism with two concentric spheres connected by six symmetry distributed springs could approximately achieve TQZS features in three rotational degrees of freedom simultaneously, thus a remarkable torsional vibration measurement performance can be guaranteed. Although due to high stiffness, the mechanism also has high anti-interference ability about force or vibration in translational directions. Mathematical modeling and numerical simulations are carried out to show the effectiveness of the proposed 3-axis sensor system in different base vibrations. In consideration of its feasibility and high performance, it can be foreseen that the proposed TQZS-based sensor will get more and more implementations in various engineering practices with torsional vibration measurements.

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Olejarova, Stefania, und Tibor Krenicky. „Water Jet Technology: Experimental Verification of the Input Factors Variation Influence on the Generated Vibration Levels and Frequency Spectra“. Materials 14, Nr. 15 (31.07.2021): 4281. http://dx.doi.org/10.3390/ma14154281.

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Vibration measurement belongs amongst the most important activities for the correct and stable operation of machines in terms of quality, economy, and safety. Monitoring the condition of the machine provides the key data for the detection of machine parts damage, thus preventing unexpected failure states and production drop-outs. Therefore, special attention is paid in the paper to the measurement and evaluation of basic parameters of vibration, particularly the frequency of vibrations and the amplitude of vibration acceleration. Experimental measurements were performed while machining the material HARDOX 500/10 on a production system using the abrasive water jet technology (AWJ) with the varied abrasive mass flow and the feed rate. By evaluating the results of measurements, recommendations of suitable and inappropriate combinations of operating parameters were formulated, widening current knowledge in the field of the abrasive parameters and the speed of movement of the technological head influence the amplitudes of vibration acceleration in the operation of production systems with AWJ technology.

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Sawicki, Charles A. „Induced Current Measurement of Rod Vibrations“. Physics Teacher 41, Nr. 1 (Januar 2003): 42–44. http://dx.doi.org/10.1119/1.1533965.

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Maskeliūnas, R., V. Maskeliūnas, Paškevičius P. und L. Ragulskis. „Measurement of vibrations of a wing“. Journal of Measurements in Engineering 4, Nr. 3 (30.09.2016): 183–87. http://dx.doi.org/10.21595/jme.2016.17772.

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Motriuk, Roman W., und Timothy Schmidt. „Rapid, Wide-Field Measurements of Complex Transient Shell Vibrations“. Journal of Pressure Vessel Technology 123, Nr. 4 (23.05.2001): 537–43. http://dx.doi.org/10.1115/1.1388286.

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The mapping and evaluation of complex vibrational fields is often highly desirable in the pressure vessel and piping industry. It is also tedious and expensive using conventional technology such as strain gage and accelerometer arrays. This paper describes field and laboratory measurements made with a portable pulsed laser system that instantaneously captures displacement data over areas up to 2 m2, with submicron sensitivity. The results indicate that pulsed holographic or electronic speckle interferometry facilitates the evaluation of nonstationary vibrational fields with significant advantages over conventional techniques. Pulsed interferometry is an effective tool for rapidly determining locations of worst-case dynamic displacements and strains. Initial field measurements at a natural gas pumping station provided an exciting glimpse at both the measurement capability of the pulsed interferometry system and never before seen dynamic responses of turbo-compressor discharge piping. The piping immediate to the compressor discharge nozzle as well as a recycle pipe was investigated at a range of operating conditions. Several characteristic patterns were observed in the instantaneous operating deflection shapes. Most notable were spiral waves progressing both clockwise and counterclockwise relative to the axial flow direction. A “shock,” sudden drop in deformation, presumably caused by instantaneous back pressure, was also captured during an extensive statistical survey. Subsequently, laboratory measurements were made on a pressure vessel built to ASME Code requirements, with various internal fluid and pressure conditions. During shaker excitation, dynamic strains logged from gage rosettes were compared to captured displacements and mode shapes. Interestingly, the ratio of circumferential to axial dynamic strains was found to depend on the operating deflection shape of the vessel. Long, thin antinodes resulted in strain ratios expected for static loading, but short antinodes typical of higher frequency responses were accompanied by significantly increased axial strains. The authors intend to continue investigating the usefulness of pulsed interferometry measurements for the oil and gas industry. It is considered important to further correlate the interferometry measurements with traditional modal analysis and strain measurement techniques. Follow-up efforts will also attempt to quantify the relationship between wide-area vibrations and noise emanation from piping systems. An additional goal is to increase the efficiency of noise abatement solutions using insight obtained from wide-field vibration measurements.

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