Vibration Acceleration Sensor Research Articles

Investigation on the multidirectional crack vibration induced by rock fracture

Understanding crack vibrations in rock under load is crucial for comprehending and predicting rock failure. With this motive, a novel multidirectional crack vibration (MCV) monitoring experiment is carried out using miniature vibration acceleration sensors with directional sensing. The obtained results show that the crack surface produced by uniaxial compression failure of rock is rough and its direction is variable. Furthermore, the volume distribution of the sample after failure is uneven, and there is a noticeable difference in mass between the broken samples on either side of the crack. Different directions of crack vibration signals were detected during rock failure, all exhibiting a strong temporal correspondence with the stress drop, but the amplitudes and main frequencies of the vibrations differ across directions. The fracture-induced crack vibration is a typical low-frequency signal, with the highest recorded frequency at 55.63 kHz and the lowest being 0.86 kHz, with the main frequency mostly below 25 kHz, which is notably lower than acoustic emission. This difference suggests that fracture-induced crack vibration and acoustic emission are distinct physical quantities. The disparities in rock vibration amplitude and main frequency among different directions, especially those perceived by opposing sensors, indicate that the two sides of the crack cannot be considered as the same vibration system. The analysis shows that the fracture-induced crack vibration of rock under load is damped vibration with a small and variable damping. Besides, due to the difference in vibration parameters on both sides of the crack, their vibration amplitude and frequency are also different. The miniature acceleration sensors used in this work can effectively capture MCV during rock failure and can be employed to further investigate the vibration precursor of rock instability failure, so as to develop appropriate assessment and prediction methods for underground dynamic disasters.

Analysis of Cavitation-induced Vibration Characteristics of a Vortex Pump Based on Adaptive Optimal Kernel Time-frequency Representation

Cavitation-induced vibration presents a significant challenge in vortex pumps, leading to potential damage to hydraulic components and adverse effects on pump performance. This study aims to investigate the long-term implications of such phenomena. To capture the vibration signals caused by cavitation, we utilized vibration acceleration sensors on the vortex pump and collected data at five predetermined measuring points under three different operating conditions. The analysis used two prominent techniques, fast Fourier transform (FFT) and adaptive optimal kernel time-frequency representation (AOK-TFR), to explore the frequency-domain and time-frequency characteristics of the vibration signals. The findings reveal a notable increase in frequency amplitude at each monitoring point as the flow rate rises. Under cavitation conditions, pronounced vibration characteristics are observed along the y-axis and z-axis of the volute, with maximum vibration intensities of 1.83 m/s² and 1.80 m/s², respectively. The frequency amplitude exhibits non-constant behavior in the time series. Moreover, variations in the time-frequency characteristics are identified with changing flow rates. A distinct signal with a frequency of 750 Hz manifests in the x-axis and y-axis of the volute when the head experiences a 3% reduction from the cavitation level.

CONFIGURATIONS OF ULTRASONIC EMITTER RESONANCE MODES FOR UNILATERAL ACCESS TO AN OBJECT

Link for citation: Azin A.V., Bogdanov E.P., Vasilyev A.V., Ponomarev S.A., Ponomarev S.V., Rikkonen S.V. Configurations of ultrasonic emitter resonance modes for unilateral access to an object. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 10, рр. 199-209. In Rus. Relevance. To prepare high-viscosity oil for transport, a number of methods are used in practice: thermal, chemical and the method of physical influences. Ultrasonic exposure of hydrocarbon raw materials is one of the physical methods. It is necessary to develop an effective method for tuning an ultrasonic emitter for maximum energy transfer into a multilayer technological medium. Aim: to study resonant operating modes of an ultrasonic emitter in a multilayer system with unilateral access to the object with simplified design of a resonance type ultrasonic emitter. Objects: oscillating system of an ultrasonic resonant type emitter, multilayer system, physical model of a system «ultrasonic emitter – multilayer system». Methods: mathematical modeling of linear oscillating system to determine the properties of oscillating system influence and technological factors on the form of vibration oscillations and on the amplitude-frequency characteristics of the system; experimental research on the basis of the physical model «ultrasonic emitter – multilayer system». Results. The authors have revealed a physical feature of the oscillatory system operation, which consists in the fact that at resonance the form of oscillations of the force signals of a multilayer piezoactor and vibration acceleration signals are purely harmonic in nature. This effect extends to operation of a resonant-type ultrasonic emitter in a short-circuit mode on a multilayer system. It was found that force and vibration acceleration amplitude-frequency characteristics of a multilayer piezoactor are similar to each other. Based on the analysis of theoretical and experimental data, the authors developed the method for adjusting the resonant operating modes of an ultrasonic emitter with unilateral access to an object. This allows simplification and reduction in the emitter design cost. The method for setting up oscillatory systems is applicable for laboratory and industrial installations. Conclusion. The research results show that in practice, harmonic shape of acceleration and force signals, as well as force amplitude of a multilayer piezoactor can be used as criteria for determining and adjusting the resonance of an oscillatory system. The oscillatory system of a resonant-type ultrasonic emitter can be tuned to resonance according to the shape and amplitude of the signal from the force sensor of the multilayer piezoactor. The force sensor is located in series with the multilayer piezoactor and does not require additional structural elements for its fastening. The ultrasonic emitter design is greatly simplified due to the absence of a vibration acceleration sensor. The method of adjusting the resonance of an oscillatory system using only a force sensor is also applied when operating a resonant-type ultrasonic emitter to a multilayer mechanical system. The developed design and technique for tuning the oscillatory system of a resonant-type ultrasonic emitter can be conveniently used when influencing process fluids through the walls of tanks and storage tanks.

Self-lubricating rubber-matrix composite incorporated with microcapsules via co-vulcanization: Elimination of friction-induced noise under dry conditions

Under extreme conditions, rubber bearings of marine stern shafts will be in a state of poor lubrication, which could cause severe wear and abnormal noise, endangering the stealth and safety of underwater vehicles. In this paper, a self--lubricating bearing material was designed by co-vulcanization method, where the nitrile butadiene rubber (NBR) and liquid NBR (LNBR) as the co-matrix and the microcapsule as the additive, named Powder-NBR/Microcapsule/LNBR (PNML). The scanning electron microscopy and thermalgravimetric analysis showed that microcapsules were well dispersed in the matrix, and the co-matrix was thermodynamically compatible. The “block-on-ring” friction test was carried out using a tribological test machine with a high-precision vibration acceleration sensor, where the ring material was composed of ZCuSn10Zn2. The results showed that the PNML had significantly lower coefficient of friction and specific wear rate, up to 84.19 % and 73.08 %, respectively, compared to the composite Matrix-NBR/LNBR (MNL) without microcapsule. The analysis of the vibration signals demonstrated that the MNL generated strong vibration and noise during friction, while the total vibration acceleration level of the PNML was reduced by 61.44 dB, as well as the line spectra and broadband noise (3300–5700 Hz) were nearly eliminated. In addition, the mechanical properties of composite were basically maintained. The findings in this study expanded the application scope of self-lubricating microcapsules, providing ideas for the design of rubber bearing materials with engineering application prospects.

Study of the dependence of the natural frequencies of a rotor system with a vertically positioned rotor on the preload

The article discusses the possibility of using a method for determining the preload force for trust and radial bearings of spindle assemblies for high-speed milling. Previously, a method was developed and tested for determining the preload force of bearing supports on high-speed grinding electrospindles with a horizontal spindle.
 The object of study is a support with angular contact bearings 7004 ACD_P4A SKF and a vertical rotor. An information-measuring system has been developed, which consists of PCB 352C34 vibration acceleration sensors, a Vishay 614 force sensor, an NI-cRIO-9056 controller, NI 9250, NI 9237 and NI 9481 modules, and software written in the National Instruments Labview language.
 The system of test actions has been improved due to its automation. Test effects began to be carried out using a solenoid with a core, which was controlled by an NI controller and developed software. Due to this, the same time delay was formed between the test action and the start of recording the vibration acceleration signal.
 Vibration acceleration signals are obtained for the entire preload range. To study the controllability of the unit, two vibration acceleration sensors were used: with a parallel and perpendicular arrangement of the axes of the direction of vibration and test action. For the first and second groups of vibration accelerations, spectral transformations were carried out, and the amplitude-frequency characteristics of the assembly were obtained for the entire range of preload values.
 As a result of the work, it was concluded that the presented methodology and criteria are applicable to high-speed milling spindle assemblies with a vertical rotor. It is also shown that this technique can be automated.

On-board vibration-based robust and unsupervised degradation detection in railway suspensions under various travelling speeds via a Multiple Model framework

A robust data-driven method for on-board vibration-based degradation detection in railway suspensions of running vehicles is introduced. The method employs two lateral vibration acceleration sensors per vehicle half, one on the bogie and one on the vehicle body. It is based on Transmittance Function data-driven models of the AutoRegressive with eXogenous excitation type within an unsupervised Multiple Model framework and aims at effective detection of early-stage component degradation while achieving robustness to varying Operating Conditions. The method is validated via thousands of Monte Carlo simulation experiments under three distinct travelling speeds. Through them, perfect detection performance is demonstrated for ‘small’ level degradation, characterised by 20 % reduction in the properties of suspension components, while even ‘minor’ degradation, characterised by 10 % reduction, is detectable but somewhat less effectively. The very good performance characteristics of the method are confirmed via field tests as well, while its superiority over alternative schemes is demonstrated via comparisons with a state-of-the-art entropy-based approach.

Measuring device for systems of technical vibro-diagnosis of power equipment

RELEVANCE. Among the various methods for assessing the technical condition of power equipment, vibration diagnostics occupies an important place. Therefore, improving the quality of hardware for vibration diagnostics is currently extremely important. THE PURPOSE. To develop a vibration sensor with a new principle of operation for systems of technical vibration diagnostics of power equipment, as well as to theoretically substantiate the performance of the proposed sensor. METHODS. When solving the set goal, the main provisions of the theory of vibration diagnostics were applied. RESULTS. A design of the vibration acceleration sensor has been developed, the peculiarity of which is that it is excited by means of constructive coupling capacitors, the first electrode of which is made in the form of a thin-walled metal split cylinder, the role of the second electrodes is performed by the lower row of the winding of each measuring coil, and the function of the inertial element is performed by a screen made in the form of a metal ring fixed on a suspension in the form of a membrane. Based on the electrical equivalent circuit of the sensor, a theoretical substantiation of its operability and efficiency was made. Variants of circuit solutions for the primary and secondary measuring transducers of the measuring device for vibration diagnostics systems have been developed. The primary measuring transducer contains directly a vibration displacement sensor, a sinusoidal voltage source, an input differential measuring amplifier and an analog filter containing a narrow-band filter, a broadband amplifier and a buffer amplifier. The secondary measuring transducer contains a quadrature detector of information signals, an output buffer amplifier and a quadrature reference voltage driver. A block diagram of the hardware solution for the vibration acceleration registration system is also proposed. CONCLUSION. The developed sensor has improved output characteristics and can be used not only for vibration control of power equipment, but also for measuring mechanical vibrations in technical diagnostic systems of various other machines and mechanisms, as well as for tasks of spectral seismic exploration.

Design and test of a FBG acceleration sensor basedon multi-stage flexible hinges.

High-precision and high-sensitivity vibration acceleration sensors have been a research hotspot in engineering technology, which play an important role in engineering structural health monitoring, earthquakes, tsunamis, and geological exploration. A novel, to the best of our knowledge, fiber Bragg grating (FBG) acceleration sensor incorporating a mass block and flexible hinge was proposed against the low sensitivity and poor transverse interference resistance of existing FBG acceleration sensors. The FBG accelerometer with the multi-stage flexible hinge was modeled and theoretically analyzed, the structural parameters of the sensor were optimized and actual sensors were developed, and a sensor performance test experiment was carried out in the end. The result suggested that the sensor's natural frequency was as high as 1400Hz, and its response was flat in the frequency range of 50-800Hz; its sensitivity was 18.4pm/g, linearity R 2 was 0.9983, and transverse interference immunity was below 3.2%. The research findings offered a new way of thinking about high-precision and high-sensitivity vibration measurement in engineering technology.

Early fault diagnosis based on reinforcement learning optimized-SVM model with vibration-monitored signals

Effective fault diagnosis maximizes economic benefits by ensuring the stability of machinery systems. Detecting the faults of the key components in machinery, such as rolling bearings, at an early stage, helps to avoid accidents to optimize the maintenance efficiency. It is well known that faulty bearings always deliver a message through their abnormal vibration variation, which can be captured by vibration acceleration sensors in order to facilitate the deteriorating status assessment. However, a clue for an early fault is so ambiguous and sometimes masked by ambient noise, which makes the early fault diagnosis a challenging problem. To tackle the problem, we propose a vibration signal-based data-driven early fault diagnosis approach based on the reinforcement learning (RL) optimized support vector machine (SVM) model. The exploration of the hyperparameter optimization using RL to improve SVM performance motivates this research. Firstly, the corresponding features in the time domain, frequency domain and time-frequency domain are extracted from the obtained vibration signals of the key components under certain working conditions. Subsequently, to better recognize the pattern of an early fault, linear discriminant analysis (LDA) is employed in fuzing the multi-domain early fault features. Finally, the fused features are fed into the RL optimized-SVM model for fault diagnosis. Experimental validation was performed with a public dataset of rolling bearings, and the results confirmed the effectiveness and superiority of the approach compared with other methods.

Cavitation state recognition for control valve using AlexNet-type neural networks with three-channel images transformed by time series

The control valve is a crucial component with high switching frequency in coal liquefaction systems. Its performance exerts a great influence on the long-term operations in the coal chemical technology. Cavitation is a key factor affecting the control accuracy and surface morphology of the control valve; hence, it will further shorten the service life of the control valve. A cavitation state recognition model based on vibration acceleration time series is proposed in this paper, and the cavitation stage in the valve is identified accurately. Three vibration acceleration sensors are attached to the valve seat to measure cavitation-induced vibration data. The collected time series is divided into fragments based on the non-overlap moving window method, and these fragments are converted into feature maps using the Gramian angular field transform. These feature maps are then input into AlexNet to train the cavitation state recognition model. The experimental results show that recognition accuracy could be improved effectively upon the increase in the length of the time series fragment, and the proposed model has a similar prediction accuracy on unfamiliar datasets. Compared with no noise, the recognition accuracy could reach to 95% when the moving window length is 150 and the signal-to-noise ratio is equal to 5 dB. Furthermore, the proposed model could still achieve good recognition results under mixed open conditions.

Real-Time Monitoring for Effects of Vibration and Temperature of Construction Site on Steel Assembly Bracing of Foundation Pit

In this paper, a real-time monitoring system—including vibration acceleration sensors, temperature sensors, and static and dynamic strain sensors—is used to monitor the safety status of a steel assembly bracing in a practical project. It uses 5G wireless networking technology to transmit monitoring data to a cloud server for early warning of abnormal changes and development trends. Real-time monitoring data obtained in a construction site are used as the inputs of the finite element model and the corresponding results of numerical simulation are compared with the results from the real-time monitoring. It can be concluded that: (1) the stress caused by environmental temperature is very significant which can be higher than the initial prestress of the steel assembly bracing; (2) the stress caused by the vertical vibration mainly from construction vehicles is not remarkable, however, the vertical frequency-weighted acceleration of support vibration is relatively large which can affect the sense of safety of engineering technicians on site; (3) the combination of the environmental temperature and vertical vibration does not affect the safety of the steel assembly bracing.

Fault Diagnosing of Cycloidal Gear Reducer Using Statistical Features of Vibration Signal and Multifractal Spectra.

The article presents a method for diagnosing cycloidal gear damage on a laboratory stand. The damage was simulated by removing the sliding sleeves from two adjacent external pins of the cycloidal gearbox. Damage to the sliding sleeves may occur under operating conditions and can lead to the destruction of the gear unit. Hence, early detection is essential. Signals from torque sensors, rotational speed sensors and vibration acceleration sensors of input and output shafts for various rotational speeds and transmission loads were recorded. The frequency analysis of these signals was carried out. Due to the fluctuation of the rotational speed, the frequency spectrum gives an approximate picture and is not useful in detecting this type of damage. The statistical characteristics of the signal were determined. However, only statistical moments of higher orders, such as kurtosis, are sensitive to the tested damage. Therefore, the use of multifractal analysis of the vibration signal using the wavelet leader method (WLMF) was considered. Then log-cumulants of the multifractal spectrum were selected as the new signal features.

A low-frequency vibration acceleration sensor based on a long-period fiber grating and a double-clamped beam

We have designed, fabricated and characterized a low-frequency vibration acceleration sensor. The sensor consists of a double-clamped beam and a long-period fiber grating (LPFG) that inscribed in a single mode fiber (SMF) by femtosecond laser. The LPFG was glued tightly to the beam top surface. Its transmission spectrum changes with beam bending, enabling vibration acceleration measurements. The experimental results display that the sensor has an accurate and steady frequency response over the frequency range of 1.5 ∼ 10 Hz with a maximum frequency response error of 4.4 %. The maximum measurable acceleration is 0.3 g, and the maximum acceleration sensitivity is 2.8 mW/g with a linearity greater than 99.6 %. The temperature drift of the sensor is less than 0.001 g/℃. The sensor has good immunity to electromagnetic interference and reliability.

Preparation of polyethylene glycol brush grafted from the surface of nitrile butadiene rubber with excellent tribological performance under aqueous lubrication

The water-lubricated bearing will be in a state of poor lubrication when marine stern shafts operate under low speed and heavy load conditions, which could cause severe wear and vibration, endangering the stealth performance of underwater vehicles. In this study, the grafting of polyethylene glycol brush was carried out on the surface of nitrile butadiene rubber (PEG-g-sNBR) by “grafting from” method. Fourier-transform-infrared-spectroscopy, nuclear-magnetic-resonance, and scanning-electron- microscope results demonstrated that the PEG-g-sNBR brush was successfully synthesized, and the reactive site was found. Using a tribological test machine with a high-precision vibration acceleration sensor, the tribological behaviors of PEG-g-sNBR were studied under aqueous lubrication. The results showed that the coefficient of friction of PEG-g-sNBR was reduced by 73.4% at 100 rpm compared to pure NBR, its microscopic wear and vibrational energy were also lower than pure NBR. Moreover, the lubrication states were revealed by friction, wear, together with the complexity of friction-induced vibration signal time series, and a lubricating film was formed on the friction surface of PEG-g-sNBR at lower rotational speed. In addition, the PEG-g-sNBR could work stably for 12 h at 300 rpm, and still maintain good tribological performance.

Tribological characteristics and mechanism of nitrile butadiene rubber coated with typical liquid lubricants

When marine stern shafts operate under low speed and heavy load conditions, the metal shaft and water-lubricated bearing will be in a state of boundary lubrication or even dry friction. Poor lubrication can cause severe wear and friction-induced vibration, endangering the stealth performance of underwater vehicles. In this study, several typical liquid lubricants, including liquid paraffin, tung oil (TO), dimethyl silicone oil (DSO), ionic liquid (IL), and hexamethylene diisocyanate (HDI) were selected as the surface coatings for nitrile butadiene rubber (NBR). Using a tribological test machine with a high-precision vibration acceleration sensor, as well as scanning electron microscopy (SEM) and other techniques, the tribological performance and mechanisms of the NBR samples coated with different lubricants were studied under various working conditions. The results showed that the liquid lubricant significantly reduced the coefficient of friction of the NBR at high rotational speeds by over 92.2%. The sample coated with HDI showed obvious tribochemical wear, and coating with the rest of the liquid lubricants decreased the specific wear rate of NBR. According to the friction-induced vibration signals, we found that an increase in loading aggravated friction-induced vibrations, and the vibrational energy was mainly concentrated in the low frequency range. The liquid paraffin and TO coatings barely changed the vibration characteristics of the NBR, while the other three lubricants produced more friction-induced self-oscillations. In conclusion, compared to the other liquid lubricants, TO exhibited the best tribological performance. The finding of this study further our understanding of the friction and vibration behaviours of polymer materials, providing a reliable basis for designing composite materials with good lubrication and vibration damping performance.

Design of conveyor separation device for potato harvester and analysis of its vibration characteristics

In view of the influence of vibration factors on the vibration characteristics of potato harvester, to study the effect of vibration parameters on the dynamic characteristics of the system and harvested potato quality, in this paper an indoor conveyor separation device for potato harvester with adjustable two-way synchronous conveying vibration parameters was designed. The device, with double-side chain drive to improve conveying efficiency and replaceable eccentric parts to change vibration parameters, allows the system to harvest potatoes under optimal working conditions. A simulation analysis of a dynamics model of the system, which was first established, was carried out. A potato soil separation test was conducted using the vibration testing system and acceleration sensor, and its data was compared with the simulation data to verify the correctness of the model. The results showed that the eccentricity, rotation speed, and inclination had an impact on the potato-soil separation rate and the vibration of the system. The analysis showed that the system had a higher potato-soil separation rate and slighter vibration under optimal working conditions, that is, eccentricity of 0.023 m, rotation speed of 130 r/min, and inclination of 26∘.

Effect of Vibration and Noise Measuring Points Distribution on the Sensitivity of Pump Cavitation Diagnosis

Cavitation is an essential factor in the deterioration of the hydraulic performance of centrifugal pumps. The study of cavitation fault diagnosis can help avoid or reduce the damage it causes. The vibration and noise analysis method can predict the incipient cavitation more accurately. In order to improve the accuracy of cavitation fault diagnosis, this paper studies the distribution of vibration and noise measuring points for centrifugal pump cavitation diagnosis. The research object is a centrifugal pump with an inducer and splitter blades. Vibration acceleration sensors and hydrophones were used to collect structural vibration and liquid-borne noise signals at different positions of the pump unit. Root-mean-square (RMS) and fast Fourier transform (FFT) methods were used to construct spectrums of vibration and noise signals with different NPSH and compare the sensitivity of different measuring points to the inception and development of cavitation. In addition, the SST k-ω turbulence model and Zwart cavitation model were used to study the cavitation volume distribution in the pump under different cavitation stages. By setting monitoring points at the impeller outlet, the frequency domain signal distribution of pressure pulsation was studied. The results show that the vibration acceleration measuring points at the pump inlet flange and pump axial position, and liquid-borne noise measuring point at the inlet position, are more sensitive to the diagnosis of cavitation fault. Motor current is also the basis for judging the inception of cavitation. Moreover, as the cavitation intensifies, the dominant frequency signal of the pressure pulsation in the pump is partially shifted.

A Robust Silicone Rubber Strip-Based Triboelectric Nanogenerator for Vibration Energy Harvesting and Multi-Functional Self-Powered Sensing.

Vibration is a common phenomenon in various fields which can not only indicate the working condition of the installation, but also serve as an energy source if it is efficiently harvested. In this work, a robust silicone rubber strip-based triboelectric nanogenerator (SRS-TENG) for vibration energy harvesting and multi-functional self-powered sensing is proposed and systematically investigated. The SRS-TENG consists of a silicone rubber strip and two aluminum electrode layers supported by polylactic acid (PLA), and acts as a sustainable power source and vibration frequency, amplitude and acceleration sensor as well. The soft contact between the aluminum electrode and silicone rubber strip makes it robust and stable even after 14 days. It can be applied in ranges of vibration frequencies from 5 to 90 Hz, and amplitudes from 0.5 to 9 mm, which shows it has advantages in broadband vibration. Additionally, it can achieve lower startup limits due to its soft structure and being able to work in multi-mode. The output power density of the SRS-TENG can reach 94.95 W/m3, matching a resistance of 250 MΩ, and it can light up more than 100 LEDs and power a commercial temperature sensor after charging capacitors. In addition, the vibration amplitude can be successfully detected and displayed on a human–machine interface. Moreover, the frequency beyond a specific limit can be distinguished by the SRS-TENG as well. Therefore, the SRS-TENG can be utilized as an in situ power source for distributed sensor nodes and a multifunctional self-powered vibration sensor in many scenarios.

Experimental study on vibration and noise of the ROEWE electric vehicle

In order to control the vibration and noise of the ROEWE electric vehicle, it is necessary to carry out the experimental study on the vibration and noise of the electric motor. Firstly, two acoustic sensors are arranged on both sides of the road to measure the pass-by noise of the electric vehicle and to analyze the influence of motor noise on the passing noise. Then, several acoustic sensors are arranged in the vehicle to measure the noise signal in the vehicle, and to analyze the characteristics of interior noise. At the same time, one acoustic sensor and three vibration acceleration sensors are arranged in the vehicle power cabin to measure the vibration signal, and measure the signals of the upper and lower vibration acceleration sensors of the powertrain mount, and analyze the vibration and noise characteristics of the motor and the vibration isolation rate of the powertrain mount. The experimental results show that the vibration of the ROEWE motor has obvious order characteristics, which is mainly composed of order components of order 8, order 16, order 24, order 40, order 48 and order 72 based on the motor output shaft speed and frequency converter switching frequency components concentrating on 10000Hz and 20000Hz. Therefore, to reduce vehicle vibration and noise from the perspective of optimizing motor vibration, the impact of cogging torque on motor vibration should be mainly considered.

Tape drive speed and vibration acceleration sensor

The design of the speed and vibration acceleration sensor of the tape drive mechanism (DSVAS) for the parameters control, in particular, the vibration and speed of the tape drive mechanism from ferromagnetic and electrically conductive bodies using the Hall sensor as the main sensitive element is considered. DSVAS has an increased linearity of the metrological characteristics and sensitivity, is easy to operate and, with further transformation, can be used as a non-destructive testing flaw detector. A mathematical model with conclusions based on the results obtained is developed. The sensor can be put to use in the field of instrumentation, mechanical engineering, energy, diagnostics, etc. Keywords metrology, technology, information systems, linearity, magnetic Reynolds number, mathematical model