Статті в журналах: "Vibration-Based Inspection"

1

Liu, Sheng, and I. Charles Ume. "Vibration Analysis Based Modeling and Defect Recognition for Flip-Chip Solder-Joint Inspection." Journal of Electronic Packaging 124, no. 3 (July 26, 2002): 221–26. http://dx.doi.org/10.1115/1.1464878.

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A novel approach for flip-chip solder joint quality inspection based on vibration analysis is presented. Traditional solder joint inspection methods have their limitations when applied to flip chips. The vibration detection method is a new approach which has advantages such as being non-contact, non-destructive, accurate, fast and applicable for in-line inspection or during process development. In this technique, a flip chip was modeled as a thick plate supported by solder bumps. Changes in solder joint quality produce different flip chip vibration responses, and also change its natural vibration frequencies. In this paper, the vibration frequencies of a flip chip on a ceramic substrate were calculated using the finite element method. Based on vibration analysis, a laser ultrasound and interferometric system was developed for flip chip solder joint quality inspection. In this system, chips with good solder joints can be distinguished from chips with bad joints using their vibration responses and frequencies. Data analysis and defect recognition methods were developed and tested. Results indicate this approach offers great promise for solder bump inspection in flip chip, BGA, and chip scale packages.

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2

Ye, Wei Jun, and Yi Min Shao. "Engine Assembly Quality Defect Inspection Based on EMD-Envelope Spectra." Key Engineering Materials 569-570 (July 2013): 962–69. http://dx.doi.org/10.4028/www.scientific.net/kem.569-570.962.

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As the complicate structure and unstable working condition, the vibration signal of engines always be non-stationary and drown in strong noise, especially for the case of slight quality defection. Such case directly results in difficulties for inspection and diagnosis of engine incipient defection. A new inspecting method based on empirical mode decomposition (EMD) and envelope spectrum is proposed in this paper. In the new method, the intrinsic mode functions (IMF) of de-noised angular vibration signals are firstly obtained; then the envelope spectrums of IMFs are obtained through envelope analysis, lastly the discrepancy of the envelope spectrums between normal and abnormal case is extracted to be the feature indicator for the engine quality inspection. This method is validated experimentally. The results show that the proposed method has an excellent performance in the quality inspecting in the presence of abnormal clearance between crankshaft and connecting rod of the engine.

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3

Zhang, Lu, Shaohua Wang, Peng Guo, and Qunsheng Wang. "Wind-Induced Vibration Response of an Inspection Vehicle for Main Cables Based on Computer Simulation." Shock and Vibration 2019 (October 30, 2019): 1–13. http://dx.doi.org/10.1155/2019/1012987.

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This paper presents a simulation approach based on the finite element method (FEM) to analyze the wind-induced vibration response of an inspection vehicle for main cables. First, two finite element (FE) models of a suspension bridge and a main cable-inspection vehicle coupled system are established using MIDAS Civil software and ANSYS software, respectively. Second, the mean wind speed distribution characteristics at a bridge site are analyzed, and the wind field is simulated based on the spectral representation method (SRM). Third, a modal analysis and a wind-induced vibration response transient analysis of the suspension bridge FE model are completed. Fourth, the vibration characteristics of the inspection vehicle are analyzed by applying fluctuating wind conditions and main cable vibration displacements in the main cable-inspection vehicle coupled FE model. Finally, based on the ISO2631-1-1997 standard, a vehicle ride comfort evaluation is performed. The results of the suspension bridge FE modal analysis are in good accordance with those of the experimental modal test. The effects of the working height, number of nonworking compressing wheels, and number of nonworking driving wheels during driving are discussed. When the average wind speed is less than 13.3 m/s, the maximum total weighted root mean square acceleration (av) is 0.1646 m/s2 and the vehicle ride comfort level is classified as “not uncomfortable.” This approach provides a foundation for the design and application of inspection vehicles.

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4

Ghazali, Mohamad Hazwan Mohd, and Wan Rahiman. "An Investigation of the Reliability of Different Types of Sensors in the Real-Time Vibration-Based Anomaly Inspection in Drone." Sensors 22, no. 16 (August 12, 2022): 6015. http://dx.doi.org/10.3390/s22166015.

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Early drone anomaly inspection is vital to ensure the drone’s safety and effectiveness. This process is often overlooked, especially by amateur drone pilots; however, some faulty conditions are difficult to notice by the naked eye or discover, even though the drone inspection process has been conducted; therefore, a real-time early drone inspection approach based on vibration data is proposed in this study. Firstly, the reliability of several microelectromechanical systems (MEMS) sensors, namely the ADXL335 accelerometer, ADXL 345 accelerometer, ADXL377 accelerometer, and SW420 vibration sensor in detecting faulty conditions, were tested and compared. The experimental results demonstrated that the vibration parameter measured using ADXL335 and ADXL345 accelerometers are the best choice as most of the faulty conditions can be detected, in contrast to other MEMS sensors. The output produced from the anomaly inspection algorithm is then converted to the “Healthy” or “Faulty” state, which is displayed in a mobile application for easy monitoring.

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5

SHINODA, Masahiro, Tetsuo MAI, Toshiaki EHARA, Susumu NAKAJIMA, Keita ABE, Keiichi FUJITA, and Munenori TSUCHIYA. "VIBRATION-BASED INSPECTION OF RAILWAY BRIDGE SUBSTRUCTURES WITH SMALL VIBRATION EXCITER AND FIBRE OPTIC SENSOR." Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering ^|^ Earthquake Engineering (SE/EE)) 69, no. 1 (2013): 40–56. http://dx.doi.org/10.2208/jscejseee.69.40.

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6

Han, Liya, Zhongwei Li, Kai Zhong, Xu Cheng, Hua Luo, Gang Liu, Junyun Shang, Congjun Wang, and Yusheng Shi. "Vibration Detection and Motion Compensation for Multi-Frequency Phase-Shifting-Based 3D Sensors." Sensors 19, no. 6 (March 19, 2019): 1368. http://dx.doi.org/10.3390/s19061368.

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Phase-shifting profilometry, especially employing the multi-frequency phase-shifting method, is increasingly used for in situ 3D metrology and for the inspection of industrial parts. However, environmental vibrations cause fatal measurement errors and are inevitable in such applications. To this end, an effective and fast vibration detection and motion compensation method for multi-frequency phase-shifting-based 3D sensors is presented. The proposed method quantitatively indicates the strength of the vibration and compensates for the motion error by revising the wrapped phase without accessing neighboring pixels. Different vibration intensities were simulated using an industrial robot moving to test the feasibility of the method. According to experiments, this method is valid and capable for 3D inspection systems affected by inevitable vibrations.

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7

Zhang, Lizheng, and I. Charles Ume. "Application of Experimental and Finite Element Modal Analysis in Development of a Novel Solder Joint Inspection Systems." Journal of Microelectronics and Electronic Packaging 5, no. 3 (July 1, 2008): 97–103. http://dx.doi.org/10.4071/1551-4897-5.3.97.

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Inspection of flip chip solder joints has been a crucial process in the electronics manufacturing industry to reduce manufacturing cost, improve yield, and ensure product quality and reliability. New inspection techniques are urgently needed to fill in the gap between available inspection capabilities and industry requirements of low-cost, fast-speed, and highly reliable inspection systems. The laser ultrasound inspection system under development aims to provide a solution that can overcome some of the limitations of current inspection techniques. This research project is based on laser ultrasound and interferometric techniques. A pulsed laser generates ultrasound on the chip's surface, and the entire chip is excited into structural vibration. An interferometer is used to measure the vibration displacement of the chip's surface at several points, and solder joints with different qualities cause different vibration responses. By analyzing the surface vibration responses, defects in solder joints may be detected and/or classified. In this paper, a broadband laser pulse is used for dynamic excitation of the chip before its vibration signature is analyzed. Experimental modal analysis extracts and estimates the modal information (mode frequencies and mode shapes) from raw vibration signals. Multiple-point surface responses are scanned with an interferometer under repeated laser pulse excitation. Spectral estimation on the raw vibration signals gives dominant-mode frequencies. The corresponding vibrational patterns are obtained by reconstructing the scanned grids using the decomposed signals at each mode frequency. Because we are interested only in the transverse vibration on the chip's surface, and because the chip's length and width are much larger than its thickness, it can be modeled as a rectangular plate with pin supports. Modal analysis by finite element modeling is applied to devices with and without defects. The objectives are to identify the differences of mode frequencies and mode shapes between good chips and chips with defects and to identify measurement points that show maximum difference in the presence and absence of defects.

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8

Sun, Hao, Wenbin Zhang, Guang Yang, Yinhua Xu, and Chunguang Suo. "DC high voltage electricity inspection device based on vibration capacitance sensor." Ferroelectrics 548, no. 1 (August 18, 2019): 150–64. http://dx.doi.org/10.1080/00150193.2019.1592522.

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9

Du, Jing, Zishuo Li, and Chao Wang. "Automated Road Damage Recognition based on the Sparse Coding Analysis of Vehicle Vibrations." MATEC Web of Conferences 271 (2019): 08006. http://dx.doi.org/10.1051/matecconf/201927108006.

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Road pavement damage inspection is a critical yet challenging task. At present, road pavement damage inspection is usually done by DOTs using a manual process. Another emerging method of inspection is via the use of sensors, such as the use of LiDAR. This study proposes an automated road damage recognition method via the Sparse Coding analysis of vehicle vibrations. Sparse Coding is a class of unsupervised methods that learn data patterns based on extracted overcomplete bases. Unlike frequency domain-based analysis, e.g. Spectral Analysis, Sparse Coding analysis preserves the temporal information of the vehicle vibration that contains important patterns related to road pavement damage. A preliminary study was performed with vehicle vibration data collected in College Station, Texas. Results confirm the feasibility of the proposed method in automated road pavement damage recognition. More data points should be collected in the future to further benchmark the effectiveness of the proposed method.

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10

Zheng, Xin, Rong Hai Liu, Zhang Qin Wu, Jin Wang, Chuan Ai, and Ying Chun Yang. "The Statistics Method Application in Acoustics Vibration Detecting Post Insulators." Applied Mechanics and Materials 696 (November 2014): 141–45. http://dx.doi.org/10.4028/www.scientific.net/amm.696.141.

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Acoustics vibration detection is detected the displacement of post insulator by inspection the change of vibration state. Hoe to indentify the situation of insulator accurately from vibration signal is fate for acoustics vibration detection. According to analyzing the vibration date with statistics method, it is proved that the vibration frequency distribution of the same type of insulator follow normal distribution. Based on this conclusion, the identification frequency section has been set for identifying breached insulators.

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11

Hsieh, Nan Kai, Wei Yen Lin, and Hong Tsu Young. "Development of Diagnosis System for Machine Tool Shaft Inspection." Advanced Materials Research 156-157 (October 2010): 1717–24. http://dx.doi.org/10.4028/www.scientific.net/amr.156-157.1717.

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Aiming at reducing cost and time of repair, condition-based shaft faults diagnosis is considered an efficient strategy for machine tool community. While the shaft with faults is operating, its vibration signals normally indicate nonlinear and non-stationary characteristics but Fourier-based approaches have shown limitations for handling this kind of signals. The methodology proposed in this research is to extract the features from shaft faults related vibration signals, from which the corresponding fault condition is then effectively identified. With an incorporation of empirical mode decomposition (EMD) method, the model applied in this research embraces some characteristics, like zero-crossing rate and energy, of intrinsic mode functions (IMFs) to represent the feature of the shaft condition.

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12

Thompson, B. D., and B. Wainscott. "Systematic Evaluation of U.S. Navy LM2500 Gas Turbine Condition." Journal of Engineering for Gas Turbines and Power 124, no. 3 (June 19, 2002): 580–85. http://dx.doi.org/10.1115/1.1451716.

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From an operational availability stand point, the U.S. Navy is interested in the short term reliability of its ship based LM2500 gas turbine engines. That is the likelihood that an engine will operate successfully through a six-month deployment (usually 1500 to 2000 operational hours). From a maintenance and cost of ownership standpoint both the short-term and long-term reliability are of concern. Long-term reliability is a measure in time (in operating hours) between engine removals. To address these requirements U.S. Navy Fleet support maintenance activities employ a system of tests and evaluations to determine the likelihood that an LM2500 will meet its short and long-term goals. The lowest level inspection is the predeployment inspection, which attempts to identify primarily mechanical faults with the engine. Gas Turbine Bulletin inspections are used to determine if predefined wear out modes exists. Performance evaluations can be performed which determine the ability of the LM2500 and its control system to meet expected power requirements. Lube oil system data can be analyzed to determine if excessive leakage or excessive scavenge temperatures exist. Engine vibration characteristics can be reviewed to identify the source of both synchronous and nonsynchronous vibration and determine if corrective measures need to be taken. This paper will discuss how the lowest level inspections feed the more sophisticated analysis and how these inspections and evaluations work to provide a systematic method of insuring both short and long-term LM2500 reliability.

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13

Xia, Yan Chun. "A Vibration Analysis and Evaluation System Construction Based on On-Line Inspection." Advanced Materials Research 605-607 (December 2012): 1164–67. http://dx.doi.org/10.4028/www.scientific.net/amr.605-607.1164.

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Vibration analysis(VA) is a very important method in the industry inspection application. Based on ISO10816, the severity level, certainty rating, the total risk rating matrix and the risk assessment index were proposed in the paper. Based on the testing samplings in a certain company and the assessment system established above, the VA analysis can be conducted and it is a good method for applying the predictive maintenance in the plant.

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14

SHINODA, Noriyuki, Yasuhiro SATO, Seigou OGATA, Hitoshi TSUNASHIMA, and Akira MATSUMOTO. "GPS speed correction method in track inspection based on car-body vibration." Proceedings of Conference of Kanto Branch 2021.27 (2021): 11F05. http://dx.doi.org/10.1299/jsmekanto.2021.27.11f05.

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15

Jiang, Kuosheng, Lianghe Li, Liubang Han, and Shuai Gou. "In-Process Quality Inspection of Rolling Element Bearings Based on the Measurement of Microelastic Deformation of Outer Ring." Shock and Vibration 2019 (May 7, 2019): 1–12. http://dx.doi.org/10.1155/2019/5656143.

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Quality inspection is the necessary procedure before bearings leaving manufacturing factories. A testing machine with low shaft speed and light radial load condition is generally used to test the dynamic quality of bearings, which avoids creating any potential damages to testing bearings. However, the signal of defective bearings is easily polluted by very weak noise using the traditional vibration-based measurement method due to the low shaft speed and light radial load condition specified for nondestructive inspection, which needs complicated and time-consuming calculation and is not suitable for online inspection. Thus, there are problems about special operating conditions and weak fault severity in quality inspection of bearings, which is quite different from the fault diagnosis of bearings. In this paper, a novel dynamic quality evaluation technique is proposed based on the measurement of Hertz deformations. The measurement system is mainly composed of an eddy current sensor, sensor fixture, and data acquisition platform with less transfer path than the vibration-based measurement system. The sensor fixture is optimized through numerical simulations to obtain signals with a high signal-to-noise ratio. Accurate evaluation of dynamic quality can be implemented reliably with simple signal processing. The proposed method can be used with a rotating speed of 100 rev/min and test load of 100 N, which is remarkably lower than the traditional quality inspection machineries with a rotating speed of around 1000 rev/min and the test load of 400 N. Both simulation and experiment studies have verified the proposed method.

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16

Surace, Cecilia. "Damage Assessment of Structures Using only Post-Damage Vibration Measurements." Key Engineering Materials 569-570 (July 2013): 11–22. http://dx.doi.org/10.4028/www.scientific.net/kem.569-570.11.

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Damage to many structural systems (including bridges, offshore platforms, airplanes and aerospace systems) can occur during normal service due to fatigue loading, a corrosive environment, collisions with extraneous objects, etc. For such structures, in order to guarantee safety, periodic inspections and maintenance are essential: Since undetected damage may result in catastrophic structural failure, the realisation of an accurate and trustworthy damage detection technique is fundamental.Vibration-based inspection offers the potential for detecting faults by monitoring the dynamic response of a structure, exploiting the fundamental principle that structural damage affects the stiffness distribution and hence the presence of the fault will change the dynamic properties of the structure under investigation.Many vibration-based inspection techniques have been developed over recent years which require knowledge of the baseline modal responses of the structure in the original undamaged state.However, for the vast majority of existing structures in operation, such data are simply not available. This keynote presentation reviews past and present research studies in which the author has been involved that aim to detect the presence of structural damage and identify its approximate location, using only post-damage vibration measurements. The techniques presented analyse either the mode shapes, operating deflection shapes or principal orthogonal modes and their corresponding derivatives. These features have been found to be good indicators of damage due to the spatial information that can be provided with respect to location of damage. The methodologies proposed are applied to isotropic/orthotropic uni/bi-dimensional structures and corresponding numerical and experimental results are presented.

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17

Arthur, N. "Optimization of vibration analysis inspection intervals for an offshore oil and gas water injection pumping system." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 219, no. 3 (August 1, 2005): 251–59. http://dx.doi.org/10.1243/095440805x8638.

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Maintenance is often considered a ‘necessary evil’ rather than a means of delivering value to owners and operators of physical assets, and means that maintenance seldom has the requisite importance and focus required. Optimal maintenance allows the delivery of maximum productivity and profit at minimum costs, and there are two ways of determining a nominally optimal maintenance solution: qualitative and quantitative optimization. Condition-based maintenance has long been recognized as an effective strategy for maintaining critical plant, and involves the regular inspection of equipment condition to determine the need for remedial maintenance activities. The periodicity at which inspections takes place is often ill-determined and appropriate quantitative analysis seldom takes place. Such an approach often leads to excessive direct costs and can result in significant indirect costs if asset failure is considered. This paper presents a solution to this problem; the quantitative delay-time maintenance model allows the determination of the optimum condition-based maintenance inspection interval. This approach is illustrated by the application of the model to the optimization of vibration analysis intervals for an offshore oil and gas water injection pumping system and demonstrates advantages when compared with conventional qualitative approaches.

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18

Bai, Lei, Rengkui Liu, and Qing Li. "Data-Driven Bias Correction and Defect Diagnosis Model for In-Service Vehicle Acceleration Measurements." Sensors 20, no. 3 (February 6, 2020): 872. http://dx.doi.org/10.3390/s20030872.

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Track quality instruments use low-cost accelerometers placed on or attached to the floors of operating trains, and these instruments collect substantial amounts of data over short inspection periods. The measurements collected by the instruments are the main data source for track irregularity evaluation. However, considerable measurement bias exists in the vertical and lateral vibration data obtained from such instruments. False positive track vibration defects detected by track quality instruments occur frequently. This results in considerable time and effort being expended needlessly because maintenance workers have to visit the railway track sites to check and review the track vibration defects. Therefore, we propose a model for data-driven bias correction and defect diagnosis for in-service vehicle acceleration measurements based on track degradation characteristics. Substantial amounts of historical track measurement data from different inspection methods were mined extensively to eliminate the false positive detection of track vibration defects and diagnose the causes of track vibration defects. Actual measurement data from the Lanxin Railway were used to validate our proposed model. The success rate achieved in identifying false positive track vibration defects was 84.1%, and that in track vibration defect diagnosis was 75.8%. These high success rates suggest that the proposed model can be of practical use in improving railway track maintenance management.

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19

Li, Ke, Lingyu Wang, JingJing Wu, Qiuju Zhang, Guanglan Liao, and Lei Su. "Using GA-SVM for defect inspection of flip chips based on vibration signals." Microelectronics Reliability 81 (February 2018): 159–66. http://dx.doi.org/10.1016/j.microrel.2017.12.032.

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20

Chen, Wenxiang, Yingna Li, and Zhengang Zhao. "Transmission Line Vibration Damper Detection Using Multi-Granularity Conditional Generative Adversarial Nets Based on UAV Inspection Images." Sensors 22, no. 5 (February 28, 2022): 1886. http://dx.doi.org/10.3390/s22051886.

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The vibration dampers can eliminate the galloping phenomenon of transmission lines caused by the wind. The detection of vibration dampers based on visual technology is an important issue. Current CNN-based methods struggle to meet the requirements of real-time detection. Therefore, the current vibration damper detection work has mainly been carried out manually. In view of the above situation, we propose a vibration damper detection-image generation model called DamperGAN based on multi-granularity Conditional Generative Adversarial Nets. DamperGAN first generates a low-resolution detection result image based on a coarse-grained module, then uses Monte Carlo search to mine the latent information in the low-resolution image, and finally injects this information into a fine-grained module through an attention mechanism to output high-resolution images and penalize poor intermediate information. At the same time, we propose a multi-level discriminator based on the multi-task learning mechanism to improve the discriminator’s discriminative ability and promote the generator to output better images. Finally, experiments on the self-built DamperGenSet dataset show that the images generated by our model are superior to the current mainstream baselines in both resolution and quality.

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21

EROL, S. Seçkin, and Cemal MERAN. "Inspection of artificially built mechanical failures through innovative condition monitoring techniques." ITM Web of Conferences 22 (2018): 01025. http://dx.doi.org/10.1051/itmconf/20182201025.

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In this study, the factors influence on root causes of failure initiation are examined with the original test implementation and condition monitoring techniques are emphasized. In working toward this goal, the laboratory test setups and tests which have been created by international research bodies are examined and in order to practise a new research work, a unique test setup system and a test plan is built. In this target of the root cause failure detection, vibration data at radial direction and electrical consumption data are collected through the analysis by comparing two different condition monitoring techniques. In this research, fault detection in modeling fault conditions and vibration, electrical consumption measurement have been let us examination in depth. During the tests, data are collected simultaneously in vibration by four-channel Data Acquisition Card (DAC) and electrical consumption by Motor Condition Monitoring (MCM) system which are integrated with an computer system. Respect to the study results; vibration analysis in detection of defects has been judged to be more successful in comparison with electric consumption analysis under the test conditions in perspective of condition based predictive maintenanceIn the study, it is mentioned that detection of failure initiations at sensitive levels and importance of consequent results.

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22

Zhou, Daocheng, Yan Yu, Jie Wang, and Zhirui Li. "Design and validation of a fast wireless low-frequency vibration inspection system for offshore platform structures." Journal of Low Frequency Noise, Vibration and Active Control 39, no. 3 (April 11, 2019): 720–28. http://dx.doi.org/10.1177/1461348419841252.

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Structural health monitoring has become increasingly important in the effective evaluation of structural health conditions and the maintenance service of structures. The validity and convenience of obtaining sensor data are critical for data mining, feature extraction, and condition assessment. A fast wireless low-frequency vibration inspection system (FWLVIS) based on wireless sensor networks for offshore platform structural vibration inspection is presented in this paper. The designed system consists of intelligent acquisition equipment and eight wireless nodes with low-frequency acceleration sensors, while the entire system has 64 collection channels. The wireless nodes integrated with a vibration sensing unit, an embedded low-power micro-processing unit, a wireless transceiver unit, and a large-capacity power unit perform functions, which could perform data collection, initial analysis, data storage, and wireless transmission. The intelligent acquisition equipment integrated with a high-performance computation unit, a wireless transceiver unit, a mobile power source, and the embedded data analysis software could completely control the multi-wireless nodes, receive and analyze the data, and implement the parameter identification. Experiments are performed on a single pendulum, and then on an offshore platform model is constructed to verify the FWLVIS. The experimental results show that the system has the following characteristics: fast arrangement, high sampling rate, high resolution, and capacity for low-frequency inspection. Thus, the system has good application prospects and practical value in the field of structural health monitoring and non-destructive inspection.

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23

Mironov, Aleksey, Pavel Doronkin, Alexander Priklonskiy, and Sergey Yunusov. "Adaptive Technology Application for Vibration-Based Diagnostics of Roller Bearings on Industrial Plants." Transport and Telecommunication Journal 15, no. 3 (September 1, 2014): 233–42. http://dx.doi.org/10.2478/ttj-2014-0021.

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Abstract Roller bearings are widely used in equipment of different applications; therefore, the issues related to the assessment of bearing technical state and localization of bearing faults are quite important and relevant. The reason is that technical state of a bearing is a critical component, which determines efficiency of a mechanism or equipment. For bearings inspection and diagnostics, various methods of vibration-based diagnostics are used. The adaptive technology for vibration-based diagnostics developed in „D un D centrs” is an effective tool for evaluation of technical state of bearings in operation compared to the existing SKF method.

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24

Zhang, Rong Pei. "Vibration Characteristics and Damage of Turbine Generator Shaft Rubbing." Applied Mechanics and Materials 697 (November 2014): 210–13. http://dx.doi.org/10.4028/www.scientific.net/amm.697.210.

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An abnormal journal vibration occurred when a 660MW turbo generator unit was in daily operation. It was identified that rubbing vibration had taken place based on the behavior of the journal vibration and the temperature change of lubricating oil. The rubbing was located inside the bearing box between the HIP rotor and the LP rotor. However, no elimination measures had been taken in time because the damage caused by rubbing was underestimated. Few months later a full inspection revealed that the LP rotor shaft had been worn out with a 70mm wide and 28mm deep groove, which greatly weakened the strength of the LP rotor. The analysis presented here may help in diagnosing and understanding rubbing-vibration-related problems in similar situations.

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25

ZHOU, Youhang. "New Approach to Inspection of Batch Drilling Quality Based on the Vibration Signal Mapping Model." Journal of Mechanical Engineering 47, no. 07 (2011): 171. http://dx.doi.org/10.3901/jme.2011.07.171.

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26

Wang, Jin Kai, Yue Lei He, Hong Yao Lu, and Zai Wei Li. "Study on Vibration Acceleration Prediction Model of Track Inspection Vehicle Based on BP Neural Network." IOP Conference Series: Materials Science and Engineering 435 (November 5, 2018): 012041. http://dx.doi.org/10.1088/1757-899x/435/1/012041.

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27

Wang, Wei-Chih, Jer-Wei Lee, Kuo-Shen Chen, and Yun-Hui Liu. "Design and vibration control of a notch-based compliant stage for display panel inspection applications." Journal of Sound and Vibration 333, no. 10 (May 2014): 2701–18. http://dx.doi.org/10.1016/j.jsv.2014.01.012.

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28

Zonta, Daniele, Matteo Pozzi, Marco Forti, and Paolo Zanon. "Vibration-Based Condition Monitoring of Smart Prefabricated Concrete Elements." Key Engineering Materials 293-294 (September 2005): 743–52. http://dx.doi.org/10.4028/www.scientific.net/kem.293-294.743.

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The University of Trento is promoting a research effort aimed at developing an innovative distributed construction system based on smart prefabricated concrete elements that can allow real-time assessment of the condition of bridge structures. So far, two reduced-scale prototypes have been produced, each consisting of a 0.2×0.3×5.6m RC beam specifically designed for permanent instrumentation with 8 long-gauge Fiber Optics Sensors (FOS) at the lower edge. The sensors employed are FBG-based and can measure finite displacements both in statics and dynamics. The acquisition module uses a single commercial interrogation unit and a softwarecontrolled optical switch, allowing acquisition of dynamic multi-channel signals from FBG-FOS, with a sample frequency of 625 Hz per channel. The performance of the system is undergoing validation in the laboratory. The scope of the experiment is to correlate changes in the dynamic response of the beams with different damage scenarios, using a direct modal strain approach. Each specimen is dynamically characterized in the undamaged state and in different condition states, simulating different cracking levels. The location and the extent of damage are evaluated through the calculation of damage indices which take into account changes in frequency and in strain-modeshapes. This paper presents in detail the results of the experiment as conducted on one of these prototypes and demonstrates how the damage distribution detected by the system is fully compatible with the damage extent appraised by inspection.

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Xuan, Menghui, Sixia Zhao, Mengnan Liu, Liyou Xu, and Xiaoliang Chen. "Inspection method of combine assembly quality based on optimized VMD." Journal of Physics: Conference Series 2125, no. 1 (November 1, 2021): 012021. http://dx.doi.org/10.1088/1742-6596/2125/1/012021.

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Abstract Aiming at the problems of low assembly accuracy and difficult to detect assembly quality of combine, a method of combine assembly quality detection based on sparrow search algorithm (SSA) optimized variational mode decomposition (VMD) and particle swarm optimization (PSO) optimized least squares support vector machine (LSSVM) was proposed, Firstly, the sparrow search algorithm is used to obtain the optimal VMD decomposition modal parameter K and penalty factor α, then the combined vibration signal of combine harvester is decomposed into intrinsic modal components of different center frequencies by using the best parameter combination [K, α]. Finally, the feature vector is used as the input of LSSVM classifier to classify different fault features. The analysis results show that the classification accuracy of SSA-VMD joint feature extraction method is 99.5%, which is 17.5% and 9.5% higher than ensemble empirical mode decomposition (EEMD) and fixed parameter VMD, which verifies the superiority of this method in the detection of combine assembly quality.

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30

Feng, Hui Juan, Jian Zhang, and Xiang Kai Liu. "Studies on Digital Shearography for Testing of Aircraft Composite Structures and Honeycomb-Based Specimen." Applied Mechanics and Materials 121-126 (October 2011): 1264–68. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.1264.

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This paper reviews shearography and its applications for testing of aircraft composite structures and honeycomb-based specimen. Shearography is a laser-based interferometry in conjunction with the digital imaging processing technique for full-field measurement of surface deformation. It reveals defects in an object by looking for defect-induced deformation anomalies. It does not require special vibration isolation, and with the development of a small and mobile measuring device (portable inspection system), it can be employed easily in field/factory environments.

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31

Liu, Xiao Zhou, Song Liang Lian, and Hong Liang Wei. "Analysis on Vibration Reduction Characteristics of Ladder Track Structure on Metro Viaduct under Measured Track Irregularities." Applied Mechanics and Materials 226-228 (November 2012): 406–10. http://dx.doi.org/10.4028/www.scientific.net/amm.226-228.406.

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3D FEM models of ladder track and rail-bearing platform track on metro viaduct were established to analyze the vibration reduction characteristics of ladder track structure. Based on track irregularities measured by track inspection car, time-history vertical accelerations of rail, sleeper, flange and beam bottom were solved to contrast the dynamic characteristics of the two track structure. Results show that the vibration level of rail and sleeper are higher on ladder track than on rail-bearing platform track, and the vibration reducing effect of ladder track for flange and beam bottom mainly embodies in frequency range of 1~40Hz in which average vibration reduction values on flange and beam bottom are 28dB and 22dB, with maximum values 40dB and 33dB. The results can provide reference for design of ladder track as well as its application in metro line.

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32

Kontarinis, Dimitrios A., and Robert D. Howe. "Tactile Display of Vibratory Information in Teleoperation and Virtual Environments." Presence: Teleoperators and Virtual Environments 4, no. 4 (January 1995): 387–402. http://dx.doi.org/10.1162/pres.1995.4.4.387.

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This paper investigates the use of tactile displays for conveying task-related vibrations in teleoperation and virtual environments. Vibration displays can be implemented with inexpensive, open loop devices that can be added to many existing systems to improve performance. We describe the design of our prototype vibration sensing and display system, and experimentally demonstrate the utility of this type of tactile feedback. We also delineate the kinds of tasks where high-frequency vibratory feedback is important. In inspection and exploration tasks the detection of vibrations can be the fundamental goal of the task, while in some manipulation tasks vibrations can enhance performance by reducing reaction times or permitting minimization of ferees. Design guidelines for implementation of vibration displays, based on simple mechanical models, are also presented.

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33

Hart, Genevieve A., Scott D. Moss, Dylan J. Nagle, and Steve C. Galea. "Endurance Testing of a Vibration Energy Harvester for Structural Health Monitoring." Advanced Materials Research 891-892 (March 2014): 1261–67. http://dx.doi.org/10.4028/www.scientific.net/amr.891-892.1261.

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The Australian Defence Science and Technology Organisation (DSTO) is developing a variety of in-situ structural health monitoring (SHM) approaches for potential use in high value platforms across the Australian Defence Force (ADF). The implementation of SHM systems would allow the ADF to move from expensive interval based inspection and maintenance regimes for ageing platforms to more cost-effective condition-based approaches, and therefore reduce aircraft through - life support costs. One critical issue is determining the optimal means of supplying power to these in-situ SHM systems. To address this issue DSTO has developed a bi-axial vibration energy harvesting approach based on a vibrating spherical-mass, magnet and wire-coil transducer arrangement. It is important that the vibration energy harvesting devices themselves are resistant to fatigue and wear related damage as they may need to operate in service for many years. This paper examines work done on mitigating wear effects in vibration energy harvesting devices, with the goal of ensuring device longevity.

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34

Chen, Yan-Chun, Ren-Hung Hwang, Mu-Yen Chen, Chih-Chin Wen, and Chih-Ping Hsu. "Screw Slot Quality Inspection System Based on Tactile Network." ACM Transactions on Internet Technology 21, no. 4 (July 22, 2021): 1–17. http://dx.doi.org/10.1145/3423556.

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The popularity of 5G networks has made smart manufacturing not limited to high-tech industries such as semiconductors due to its high speed, ultra-high reliability, and low latency. With the advance of system on chip (SoC) design and manufacturing, 5G is also suitable for data transmission in harsh manufacturing environments such as high temperatures, dust, and extreme vibration. The defect of the screw head is caused by the wear and deformation of the die forming the head after mass production. Therefore, the screw quality inspection system based on the tactile network in this article monitors the production quality of the screw; the system will send a warning signal through the router to remind the technician to solve the production problem when the machine produces a defective product. Sensors are embedded into the traditional screw heading machine, and sensing data are transmitted through a gateway to the voluntary computing node for screw slot quality inspection. The anomaly detection data set collected by the screw heading machine has a ratio of anomaly to normal data of 0.006; thus, we propose a time-series deep AutoEncoder architecture for anomaly detection of screw slots. Our experimental results show that the proposed solution outperforms existing works in terms of efficiency and that the specificity and accuracy can reach 97% through the framework proposed in this article.

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35

Xu, Hao, Zhongqing Su, Li Cheng, and Jean-Louis Guyader. "On a hybrid use of structural vibration signatures for damage identification: a virtual vibration deflection (VVD) method." Journal of Vibration and Control 23, no. 4 (August 8, 2016): 615–31. http://dx.doi.org/10.1177/1077546315581944.

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A damage identification method named virtual vibration deflection (VVD) was developed, the principle of which was formulated based on the “weak” modality of the pseudo-excitation (PE) approach previously established. In essence, VVD is based on locating structural damage within a series of “sub-regions” divided from the entire structure under inspection, and each sub-region was considered as a “virtual” structure undergoing independent vibration. The corresponding vibration deflection of the “virtual” structure was then used to derive the damage index of VVD. Besides various advantages inheriting from the PE approach, for example, capability of detecting damage without baseline signals and pre-developed benchmark structures, VVD exhibits improved detection accuracy and particularly enhanced noise immunity compared with the PE approach, attributed to a hybrid use of multi-types of vibration signatures (MTVS). As a proof-of-concept investigation, a beam model was used in a numerical study to examine the philosophy of VVD. And the influences from different factors (i.e., level of measurement noise and measurement density) on the detection accuracy of VVD were discussed based on the numerical model. An experiment was carried out subsequently to identify the locations of multiple defects contained in an aluminum beam-like structure. Identification results constructed by the PE approach, VVD using single-type of vibration signatures, and VVD using MTVS, were presented, respectively, for the purpose of comparison.

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36

Shin, Yun-Ho, Seok-Jun Moon, Yong-Ju Kim, and Ki-Yong Oh. "Vibration Control of Scanning Electron Microscopes with Experimental Approaches for Performance Enhancement." Sensors 20, no. 8 (April 17, 2020): 2277. http://dx.doi.org/10.3390/s20082277.

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A vibration isolator embedded in precision equipment, such as a scanning electron microscope (SEM), wafer inspection equipment, and nanoimprint lithography equipment, play a critical role in achieving the maximum performance of the equipment during the fabrication of nano/micro-electro-mechanical systems. In this study, the factors that degrade the performance of SEM equipment with isolation devices are classified and discussed, and improvement measures are proposed from the viewpoints of the measured image patterns and vibrations in comparison with the relevant vibration criteria. In particular, this study quantifies the image patterns measured using SEMs, and the results are discussed along with the measured vibration. A guide for the selection of mounting equipment is presented by performing vibration analysis on the lower mount of the dual elastic mount configuration applied to the SEM, as well as the image patterns analyzed with that configuration. In addition, design modifications for the mount and its arrangement are suggested based on impact tests and numerical simulations.

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37

Iliopoulos, Ilias A., John S. Sakellariou, Spilios D. Fassois, Elias Chronopoulos, Alexandros Deloukas, Christos Giannakis, Dimosthenis Kapiris, et al. "On-board vibration-based remaining useful life estimation of hollow worn railway vehicle wheels." Journal of Physics: Conference Series 2184, no. 1 (March 1, 2022): 012023. http://dx.doi.org/10.1088/1742-6596/2184/1/012023.

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Abstract The feasibility of on-board remaining useful life (RUL) estimation of hollow worn railway vehicle wheels under varying travelling speed using vibration signals from the vehicle’s bogie, is for the first time explored. A variant of the Multiple Model Power Spectral Density (MM-PSD) method is employed, treating RUL estimation as a multi-class classification problem, where each class corresponds to a specific condition of hollow worn wheels associated with an empirical remaining mileage. The method classifies the current, unknown, condition of hollow worn wheels to one of the available by examining the vehicular dynamics similarity among them through the amplitude of the sharp periodic valleys (antiresonances) induced due to the Wheelbase Filtering (WF) effect. The vibration signals are obtained from Monte Carlo experiments based on the high-fidelity SIMPACK software, while the remarkable performance of the method is demonstrated via thousands of inspection cases.

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38

McGetrick, Patrick J., and Chul Woo Kim. "A Parametric Study of a Drive by Bridge Inspection System Based on the Morlet Wavelet." Key Engineering Materials 569-570 (July 2013): 262–69. http://dx.doi.org/10.4028/www.scientific.net/kem.569-570.262.

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Many of the bridges currently in use worldwide are approaching the end of their design lives. However, rehabilitating and extending the lives of these structures raises important safety issues. There is also a need for increased monitoring which has considerable cost implications for bridge management systems. Existing structural health monitoring (SHM) techniques include vibration-based approaches which typically involve direct instrumentation of the bridge and are important as they can indicate the deterioration of the bridge condition. However, they can be labour intensive and expensive. In the past decade, alternative indirect vibration-based approaches which utilise the response of a vehicle passing over a bridge have been developed. This paper investigates such an approach; a low-cost approach for the monitoring of bridge structures which consists of the use of a vehicle fitted with accelerometers on its axles. The approach aims to detect damage in the bridge while obviating the need for direct instrumentation of the bridge. Here, the effectiveness of the approach in detecting damage in a bridge is investigated using a simplified vehicle-bridge interaction (VBI) model in theoretical simulations and a scaled VBI model in a laboratory experiment. In order to identify the existence and location of damage, the vehicle accelerations are recorded and processed using a continuous Morlet wavelet transform and a damage index is established. A parametric study is carried out to investigate the effect of parameters such as the bridge span length, vehicle speed, vehicle mass, damage level and road surface roughness on the accuracy of results.

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39

Combet, F., L. Gelman, P. Anuzis, and R. Slater. "Vibration detection of local gear damage by advanced demodulation and residual techniques." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 223, no. 5 (April 15, 2009): 507–14. http://dx.doi.org/10.1243/09544100jaero450.

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Damage detection in a gearbox is reported based on analysis of vibration signals measured on a running aircraft engine on a test bed. The experiment was stopped due to material being found on the magnetic chip detectors in the oil system. Subsequent inspection found a significant damage to a bevel gear inside the drive train system. Three damage detection techniques are applied to the vibration signals: advanced demodulation, advanced residual technique, and the classical residual technique. Fault indicators are defined from each technique and trended over time. Results show that these techniques have the ability to provide early damage detection; however, with some noticeable difference in their feature evolution. The advantages of the techniques are compared and discussed.

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40

Soe, Theint Theint Thu, and San Yu Khaing. "Evaluation of Cable Force Changes Effects on Cable Stayed Bridge." Civil Engineering Journal 6, no. 11 (November 1, 2020): 2159–74. http://dx.doi.org/10.28991/cej-2020-03091609.

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The proposed bridge, which is cable stayed bridge crosses the Hlaing River that flows through Western Yangon. It was completed in 2000 and is currently used to connect Insein Township with Hlaing Tharyar Township. It has the 20 years’ service life. It requires the inspection and the evaluation of the real condition of the structure. As cable element plays an important role in cable structures, evaluation of the real state of the stay cable is one of the main focuses of the cable stayed bridge. Firstly, in the research work all cables are inspected to evaluate the current condition of the cables with included visual inspection and vibration-based cable force measurement method. With the help of static and moving load analysis, the effect of force change cables in which the successive force changes are considered, and the possible cable loss effect on the structural behavior of the bridge are also investigated. The finite element model of the cable stayed bridge is developed based on the geometric shape and material properties from MOC and is modelled with finite element software MIDAS Civil. The tension forces obtained by inspection over years (2000 to 2018) using vibration-based measurements method are compared with the measured intact cable forces. According to the results of the data analysis, it is observed that the cables force variations of the seven cables are abnormal conditions. In order to evaluate the condition of a bridge effected by cable force variation, the two parameters are considered; percentage increase in tension stress of all cables and percentage increase in deflection of the deck. The present study describes the structural response of the bridge in order to evaluate the actual safety of the bridge with abnormal force change cables, and also examines the consequences of one cable failure. Doi: 10.28991/cej-2020-03091609 Full Text: PDF

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41

Zhao, Jie, Jianhui Lin, Jinbao Yao, and Jianming Ding. "Two-Dimensional Impact Reconstruction Method for Rail Defect Inspection." Mathematical Problems in Engineering 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/236574.

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The safety of train operating is seriously menaced by the rail defects, so it is of great significance to inspect rail defects dynamically while the train is operating. This paper presents a two-dimensional impact reconstruction method to realize the on-line inspection of rail defects. The proposed method utilizes preprocessing technology to convert time domain vertical vibration signals acquired by wireless sensor network to space signals. The modern time-frequency analysis method is improved to reconstruct the obtained multisensor information. Then, the image fusion processing technology based on spectrum threshold processing and node color labeling is proposed to reduce the noise, and blank the periodic impact signal caused by rail joints and locomotive running gear. This method can convert the aperiodic impact signals caused by rail defects to partial periodic impact signals, and locate the rail defects. An application indicates that the two-dimensional impact reconstruction method could display the impact caused by rail defects obviously, and is an effective on-line rail defects inspection method.

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42

Miwa, Takashi, and Yuri Nakazawa. "Nondestructive Evaluation of Localized Rebar Corrosion in Concrete Using Vibro-Radar Based on Pulse Doppler Imaging." Remote Sensing 14, no. 18 (September 16, 2022): 4645. http://dx.doi.org/10.3390/rs14184645.

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Early nondestructive inspection of rebar corrosion in reinforced concrete structures is important, but a practical, accurate, high-speed, and high-resolution method has not yet been proposed. We have proposed a vibro-Doppler radar (VDR) method for quantitative evaluation of rebar corrosion based on vibration displacement of a rebar sinusoidally vibrated by an excitation coil. However, this method is not practical because it is not quick enough, requiring two minutes for a measurement at one point. In this paper, a VDR system based on a pulse radar, which is 100 times faster than the conventional system, was developed, and its effectiveness was verified using a concrete specimen. As a result, it was found that a 30-cm section could be scanned in about 2 min. Furthermore, the vibration displacements spatially distributed on the rebar were monitored while the rebar was corroded by electrolytic corrosion tests. As a result, it was found that the vibration displacement increased locally with a width of a few centimeters, and their positions corresponded to the positions of sectional loss of rebar due to corrosion, indicating that this method can be used for nondestructive evaluation of localized rebar corrosion.

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43

Jia, Fangyun, and Dawei Wang. "Research on Computer Vibration Test System of Rotating Machinery Based on Wavelet Transform in Auto Parts Inspection." Journal of Physics: Conference Series 1648 (October 2020): 022055. http://dx.doi.org/10.1088/1742-6596/1648/2/022055.

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44

Tsai, Hsin-Chu, Chung-Yue Wang, Norden E. Huang, Tsai-Wen Kuo, and Wei-Hua Chieng. "Railway track inspection based on the vibration response to a scheduled train and the Hilbert–Huang transform." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 229, no. 7 (April 8, 2014): 815–29. http://dx.doi.org/10.1177/0954409714527930.

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45

Wang, Hesheng, Weidong Chen, Lifei Xu, and Tao He. "Vision-based online vibration estimation of the in-vessel inspection flexible robot with short-time Fourier transformation." Fusion Engineering and Design 98-99 (October 2015): 1683–87. http://dx.doi.org/10.1016/j.fusengdes.2015.06.181.

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46

Dong, Guangming, Jin Chen, and Fagang Zhao. "Monitoring of the Looseness in Cargo Bolts under Random Excitation Based on Vibration Transmissibility." Shock and Vibration 2021 (May 7, 2021): 1–12. http://dx.doi.org/10.1155/2021/8841940.

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Bolted joints are widely used in industrial applications and joint failure can cause a disastrous accident if loosening happens. Bolt loosening detection can be made by regular manual inspection or by using sensors based on different physical principles, such as acoustoelastic effect, piezoelectric active sensing, and electromechanical impedance. Compared with the above methods, vibration based bolt looseness monitoring using accelerometers is appealing for its economy and convenience for measurement. In this paper, cargo bolts looseness monitoring under random excitation is studied based on vibration transmissibility, which overcomes the drawback of commonly used vibration methods in finding local bolt looseness. Vibration transmissibility analysis only uses two vibration transducers to monitor bolt group looseness, where the vibration signal below the cargo bolts is used as the “input” and the other one above the cargo bolts is used as the “output.” There are 12 bolts in the cargo bolts studied in this paper, providing an essential clamping force to fix cargo during transportation. Six kinds of bolt group looseness with an increasing degree are simulated in the experiment. The experimental analysis shows that variation of the spectral moment can be used to monitor the global variation of the torque wrench exerted on the cargo bolts. The early stage of the bolt group looseness is that some one or two bolts begin to loose; however, the spectrum moment factor is insensitive to the local bolt looseness in the bolt group. To address this issue, the eigensystem realization algorithm (ERA) based on random input and output is utilized to find the subtle eigenvalue variation of the system matrix, which is neglected by the frequency transmissibility function. The experimental results show the effectiveness of the proposed method for detecting local bolt looseness.

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47

Zulkifli, Muhammad Nubli, Fuaida Harun, and Azman Jalar. "Effect of surface roughness and hardness of leadframe on the bondability of gold wedge bonds." Microelectronics International 36, no. 2 (April 1, 2019): 62–67. http://dx.doi.org/10.1108/mi-08-2018-0053.

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Purpose This paper aims to analyze the effect of surface roughness and hardness of leadframe on the bondability of gold (Au) wedge bond using in situ inspection of laser interferometer and its relationship with the deformation and wire pull strength. Design/methodology/approach The in situ inspection of ultrasonic vibration waveform through the changes of vertical axis (y-axis) amplitude of wire bonder capillary was carried out using laser interferometer to analyze the formation of Au wedge bond. The relationship between the changes of ultrasonic waveform of capillary with the deformation and the pull strength was analyzed to evaluate the bondability of Au wedge bonds. Findings It was observed that the changes in vertical axis amplitude of ultrasonic vibration waveform of wire bonder capillary can be used to describe the process of bonding formation. The loss of ultrasonic energy was exhibited in ultrasonic vibration waveform of wire bonding on leadframe that has higher value of roughness (leadframe A) as compared to that of leadframe that has lower value of roughness (leadframe B). The lower pull strength obtained by Au wedge bond further confirms the reduction of bond formation because of the higher deformation on leadframe A as compared to that of leadframe B. Originality/value The relationship between in situ measurement using laser interferometer with the bondability or deformation and wire pull strength of Au wedge bonds on different surface roughness and hardness of leadframes is still lacking. These findings provide a valuable data in analyzing the bonding mechanisms that can be identified based on the in situ measurement of ultrasonic vibration and the bondability of Au wedge bonds.

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48

Chen, Lei, Jie Han, Ling Jun Li, and Wei Hao. "Development of an Instrument for Machine Equipment State Inspection and Safety Evaluation Based on Embedded Technology." Applied Mechanics and Materials 235 (November 2012): 413–18. http://dx.doi.org/10.4028/www.scientific.net/amm.235.413.

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In modern industry, plant equipment must be maintained effectively to guarantee safety operation. An intelligent instrument for plant equipment state inspection and safety evaluation was developed based on embedded technology. Firstly, the overall structure of the instrument system was introduced. Then the mainboard circuits were designed based on ARM core microprocessor. The control logics of the dynamic machine signals acquisition subsystem were designed by using of a complex programmable logic device. After that, the embedded operating system was transplanted and device drivers were programmed. Finally, the functions of the applications were stated. The designed instrument can meet the needs of the vibration acquisition of the rotating machines satisfactorily and provide effective means for equipment maintenance.

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49

Aravanis, Tryfon-Chrysovalantis, Spiros Kolovos, John Sakellariou, and Spilios Fassois. "Random vibration based damage detection for a composite beam under environmental and operational variability via a stochastic Functional Model based method." MATEC Web of Conferences 188 (2018): 01003. http://dx.doi.org/10.1051/matecconf/201818801003.

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The problem of random vibration response based damage detection for a composite beam under non-measurable environmental and operational variability, presently temperature and tightening torque, is considered via a Functional Model based method. The method is based on proper representation of the healthy structural dynamics under any environmental/operating conditions via a data based Functional Model obtained in the method’s baseline phase and used to define a ‘healthy subspace’. Damage detection is, in the method’s inspection phase, achieved by examining whether or not the current dynamics belongs to the healthy subspace. The experimental results obtained for damage detection on a composite beam indicate excellent detection performance, with correct detection rate of 100% for false alarm rate as small as 1%. The superiority of the proposed method is confirmed via comparisons with a state-of-the-art Principal Component Analysis based method.

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50

Zhao, Can, C. R. Tang, and S. Wan. "Multisensor Information Fusion Based on D-S Evidence Theory and BP Neural Network." Key Engineering Materials 567 (July 2013): 113–17. http://dx.doi.org/10.4028/www.scientific.net/kem.567.113.

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This paper applies the information fusion technology to tool monitoring. As one of the most important processing factor, the cutting tool and the tool wear directly influence size precision. Signals of cutting force and vibration are measured with multi-sensor. By using multi-sensor the drawbacks can be overcome, the multi-sensor information fusion mentioned in manufacture stands for extracting kinds of information from different sensors (especially for cutting force and vibration signal in this paper), making best use of all resources，according to certain criterion to judge the spatial and time redundancy , to make the system more comprehensive. Two data fusion methods, which are BP Neural Network and Wavelet Neural Network for predicting tool wear, and are debated. By the hybrid of BP and wavelet based neural network the cutting tool status inspection system is built so that the forecast of tool wear can be achieved. The results show experimentally two of these presented methods effectively implement tool wear monitoring and predicting.

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