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Analysis And Modeling Of Planetary Gearbox Vibration Data For Early Fault Detection
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Book Synopsis Analysis and Modeling of Planetary Gearbox Vibration Data for Early Fault Detection by : Lawrence Yip
Download or read book Analysis and Modeling of Planetary Gearbox Vibration Data for Early Fault Detection written by Lawrence Yip and published by . This book was released on 2011 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: Planetary gearboxes are key rotating motion transmission components used in many types of machinery. Syncrude Canada uses planetary gearboxes in their Fort McMurray oil sands field operations to transport stockpile for further downstream processing. There is currently no condition monitoring capability for these gearboxes. As such, unexpected failures are not detected in advance. Failure of these gearboxes results in costly bottlenecks and secondary damages. Routine inspections to check on condition of the gearbox, requiring the gearbox to be off-line, are also costly.This thesis investigates into condition monitoring for Syncrude's planetary gearbox through analyzing the data collected at a test rig that is modeled after the one used in field operations. The condition at specific points in the testing is analyzed, and the desired fault to be detected early is identified. The Time Synchronous Averaging (TSA) preprocessing technique is applied to the original data, and results show that it is superior for modeling purposes. Health indicators and statistical control charts are applied based on the TSA model, and show clear indication of deterioration.
Book Synopsis Dynamics Based Vibration Signal Modeling and Fault Detection of Planetary Gearboxes by : Xihui Liang
Download or read book Dynamics Based Vibration Signal Modeling and Fault Detection of Planetary Gearboxes written by Xihui Liang and published by . This book was released on 2016 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vibration analysis has been widely used to detect gear tooth fault inside a planetary gearbox. However, the vibration characteristics of a planetary gearbox are very complicated. Inside a planetary gearbox, there are multiple vibration sources as several sun-planet gear pairs and several ring-planet gear pairs are meshing simultaneously. In addition, due to the rotation of the carrier, distance varies between vibration sources and a transducer installed on gearbox housing. This thesis aims to simulate and understand the vibration signals of a planetary gear set, and then propose a signal processing method to detect gear tooth fault more effectively. First, an analytical method derives the equations of a healthy planetary gear set's time-varying gear mesh stiffness. Then, a gear tooth crack growth model is proposed and equations are derived to quantify the effect of gear tooth crack on the time-varying mesh stiffness. After that, a two-dimensional lumped-mass model is developed to simulate the vibration source signals of a planetary gear set; an analytical model is proposed to represent the effect of transmission path; and the resultant vibration signals of a planetary gear set at a sensor location are generated by considering multiple vibration sources and the effect of transmission path. Finally, a signal decomposition method is proposed to detect a single tooth crack in a single planet gear and experimental validation is performed. The methods proposed in this thesis help us understand the vibration properties of planetary gearboxes and give insights into developing new signal processing methods for gear tooth fault detection.
Book Synopsis Early Fault Detection for Gear Shaft and Planetary Gear Based on Wavelet and Hidden Markov Modeling by : Jing Yu
Download or read book Early Fault Detection for Gear Shaft and Planetary Gear Based on Wavelet and Hidden Markov Modeling written by Jing Yu and published by . This book was released on 2011 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fault detection and diagnosis of gear transmission systems have attracted considerable attention in recent years, due to the need to decrease the downtime on production machinery and to reduce the extent of the secondary damage caused by failures. However, little research has been done to develop gear shaft and planetary gear crack detection methods based on vibration signal analysis. In this thesis, an approach to gear shaft and planetary gear fault detection based on the application of the wavelet transform to both the time synchronously averaged (TSA) signal and residual signal is presented. Wavelet approaches themselves are sometimes inefficient for picking up the fault signal characteristic under the presence of strong noise. In this thesis, the autocovariance of maximal energy wavelet coefficients is first proposed to evaluate the gear shaft and planetary gear fault advancement quantitatively. For a comparison, the advantages and disadvantages of some approaches such as using variance, kurtosis, the application of the Kolmogorov-Smirnov test (K-S test), root mean square (RMS) , and crest factor as fault indicators with continuous wavelet transform (CWT) and discrete wavelet transform (DWT) for residual signal, are discussed. It is demonstrated using real vibration data that the early faults in gear shafts and planetary gear can be detected and identified successfully using wavelet transforms combined with the approaches mentioned above.In the second part of the thesis, the planetary gear deterioration process from the new condition to failure is modeled as a continuous time homogeneous Markov process with three states: good, warning, and breakdown. The observation process is represented by two characteristics: variance and RMS based on the analysis of autocovariance of DWT applied to the TSA signal obtained from planetary gear vibration data. The hidden Markov model parameters are estimated by maximizing the pseudo likelihood function using the EM iterative algorithm. Then, a multivariate Bayesian control chart is applied for fault detection. It can be seen from the numerical results that the Bayesian chart performs better than the traditional Chi-square chart.
Book Synopsis Dynamics-Based Vibration Signal Modeling for Tooth Fault Diagnosis of Planetary Gearboxes by : Xihui Liang
Download or read book Dynamics-Based Vibration Signal Modeling for Tooth Fault Diagnosis of Planetary Gearboxes written by Xihui Liang and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Vibration analysis has been widely used to diagnose gear tooth fault inside a planetary gearbox. However, the vibration characteristics of a planetary gearbox are very complicated. Inside a planetary gearbox, there are multiple vibration sources as several sun-planet gear pairs, and several ring-planet gear pairs are meshing simultaneously. In addition, due to the rotation of the carrier, distance varies between vibration sources and a transducer installed on the planetary gearbox housing. Dynamics-based vibration signal modeling techniques can simulate the vibration signals of a planetary gearbox and reveal the signal generation mechanism and fault features effectively. However, these techniques are basically in the theoretical development stage. Comprehensive experimental validations are required for their future applications in real systems. This chapter describes the methodologies related to vibration signal modeling of a planetary gear set for gear tooth damage diagnosis. The main contents include gear mesh stiffness evaluation, gear tooth crack modeling, dynamic modeling of a planetary gear set, vibration source modeling, modeling of transmission path effect due to the rotation of the carrier, sensor perceived vibration signal modeling, and vibration signal decomposition techniques. The methods presented in this chapter can help understand the vibration properties of planetary gearboxes and give insights into developing new signal processing methods for gear tooth damage diagnosis.
Book Synopsis Early Fault Detection and Optimal Maintenance Control for Partially Observable Systems Subject to Vibration Monitoring by : Chen Lin
Download or read book Early Fault Detection and Optimal Maintenance Control for Partially Observable Systems Subject to Vibration Monitoring written by Chen Lin and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Advances in Condition Monitoring of Machinery in Non-Stationary Operations by : Giorgio Dalpiaz
Download or read book Advances in Condition Monitoring of Machinery in Non-Stationary Operations written by Giorgio Dalpiaz and published by Springer Science & Business Media. This book was released on 2013-10-05 with total page 678 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the processing of the third edition of the Condition Monitoring of Machinery in Non-Stationary Operations (CMMNO13), which was held in Ferrara, Italy. This yearly event merges an international community of researchers who met – in 2011 in Wroclaw (Poland) and in 2012 in Hammamet (Tunisia) – to discuss issues of diagnostics of rotating machines operating in complex motion and/or load conditions. The growing interest of the industrial world on the topics covered by the CMMNO13 involves the fields of packaging, automotive, agricultural, mining, processing and wind machines in addition to that of the systems for data acquisition. The participation of speakers and visitors from industry makes the event an opportunity for immediate assessment of the potential applications of advanced methodologies for the signal analysis. Signals acquired from machines often contain contributions from several different components as well as noise. Therefore, the major challenge of condition monitoring is to point out the signal content that is related to the state of the monitored component particularly in non-stationary conditions.
Book Synopsis Planetary gearbox fault detection using vibration separation techniques by :
Download or read book Planetary gearbox fault detection using vibration separation techniques written by and published by . This book was released on 2011 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis A Model Based Framework for Fault Diagnosis and Prognosis of Dynamical Systems with an Application to Helicopter Transmissions by : Romano Patrick-Aldaco
Download or read book A Model Based Framework for Fault Diagnosis and Prognosis of Dynamical Systems with an Application to Helicopter Transmissions written by Romano Patrick-Aldaco and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The thesis presents a framework for integrating models, simulation, and experimental data to diagnose incipient failure modes and prognosticate the remaining useful life of critical components, with an application to the main transmission of a helicopter. Although the helicopter example is used to illustrate the methodology presented, by appropriately adapting modules, the architecture can be applied to a variety of similar engineering systems. Models of the kind referenced are commonly referred to in the literature as physical or physics-based models. Such models utilize a mathematical description of some of the natural laws that govern system behaviors. The methodology presented considers separately the aspects of diagnosis and prognosis of engineering systems, but a similar generic framework is proposed for both. The methodology is tested and validated through comparison of results to data from experiments carried out on helicopters in operation and a test cell employing a prototypical helicopter gearbox. Two kinds of experiments have been used. The first one retrieved vibration data from several healthy and faulted aircraft transmissions in operation. The second is a seeded-fault damage-progression test providing gearbox vibration data and ground truth data of increasing crack lengths. For both kinds of experiments, vibration data were collected through a number of accelerometers mounted on the frame of the transmission gearbox. The applied architecture consists of modules with such key elements as the modeling of vibration signatures, extraction of descriptive vibratory features, finite element analysis of a gearbox component, and characterization of fracture progression. Contributions of the thesis include: (1) generic model-based fault diagnosis and failure prognosis methodologies, readily applicable to a dynamic large-scale mechanical system; (2) the characterization of the vibration signals of a class of complex rotary systems through model-based techniques; (3) a "reverse engineering" approach for fault identification using simulated vibration data; (4) the utilization of models of a faulted planetary gear transmission to classify descriptive system parameters either as fault-sensitive or fault-insensitive; and (5) guidelines for the integration of the model-based diagnosis and prognosis architectures into prognostic algorithms aimed at determining the remaining useful life of failing components.
Book Synopsis Mechanical Fault Diagnosis and condition monitoring by : R. Collacott
Download or read book Mechanical Fault Diagnosis and condition monitoring written by R. Collacott and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although the most sophisticated fault diagnosis and condition monitoring systems have their origin in the aerospace and nuclear energy industries, their use is by no means restricted to such areas of 'high technology'. Modern machinery in most industrial plants is now so complex and expensive that mechanics find it increas ingly difficult to detect failure by, for instance, recognising changes in sound 'signatures', and few plants can afford the luxury of regular 'stripping down'. Increasingly, therefore, eady-warning devices are being employed in an effort to prevent catastrophic breakdown. This book provides the first co-ordinated compilation of fault diagnosis and con dition monitoring devices. It proceeds in three logical steps. The eady chapters deal with those conditions which contribute to deterioration and the consequent likely development of faults. The middle part of the book considers the various tech niques of monitoring and discusses the criteria for their selection in different situ ations. The final chapters provide a guide to the interpretation of the information signals deriving from monitoring, relating to reliability science and the mathematics of probability, and thus providing decision data on which management can act.
Book Synopsis Proceedings of the TEPEN International Workshop on Fault Diagnostic and Prognostic by : Tongtong Liu
Download or read book Proceedings of the TEPEN International Workshop on Fault Diagnostic and Prognostic written by Tongtong Liu and published by Springer Nature. This book was released on with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Development of Effective Gearbox Fault Diagnosis Methodologies Utilising Various Levels of Prior Knowledge by : Stephan Schmidt
Download or read book Development of Effective Gearbox Fault Diagnosis Methodologies Utilising Various Levels of Prior Knowledge written by Stephan Schmidt and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Effective fault diagnosis techniques are important to ensure that expensive assets such as wind turbines can operate reliably. Vibration condition monitoring data are rich with information pertaining to the dynamics of the rotating machines and are therefore popular for rotating machine diagnostics. However, vibration data do not only contain diagnostic information, but operating condition information as well. The performance of many conventional fault diagnosis techniques is impeded by inherent varying operating conditions encountered in machines such as wind turbines and draglines. Hence, it is not only important to utilise fault diagnosis techniques that are sensitive to faults, but the techniques should also be robust to changes in operating conditions. Much research has been conducted to address the many facets of gearbox fault diagnosis e.g. understanding the interactions of the components, the characteristics of the vibration signals and the development of good vibration analysis techniques. The aforementioned knowledge, as well as the availability of historical data, are regarded as prior knowledge (i.e. information that is available before inferring the condition of the machine) in this thesis. The available prior knowledge can be utilised to ensure that e ective gearbox fault diagnosis techniques are designed. Therefore, methodologies are proposed in this work which can utilise the available prior knowledge to e ectively perform fault diagnosis, i.e. detection, localisation and trending, under varying operating conditions. It is necessary to design di erent methodologies to accommodate the di erent kinds of historical data (e.g. healthy historical data or historical fault data) that can be encountered and the di erent signal analysis techniques that can be used. More speci cally, a methodology is developed to automatically detect localised gear damage under varying operating conditions without any historical data being available. The success of the methodology is attributed to the fact that the interaction between gear teeth in a similar condition results in data being generated which are statistically similar and this prior knowledge may be utilised. Therefore, a dissimilarity measure between the probability density functions of two teeth can be used to detect a gear tooth with localised gear damage. Three methodologies are also developed to utilise the available historical data from a healthy machine for gearbox fault diagnosis. Firstly, discrepancy analysis, a powerful novelty detection technique which has been used for gear diagnostics under varying operating conditions, is extended for bearing diagnostics under varying operating conditions. The suitability of time-frequency analysis techniques and di erent models are compared for discrepancy analysis as well. Secondly, a methodology is developed where the spectral coherence, a powerful second-order cyclostationary technique, is supplemented with healthy historical data for fault detection, localisation and trending. Lastly, a methodology is proposed which utilises narrowband feature extraction methods such as the kurtogram to extract a signal rich with novel information from a vibration signal. This is performed by attenuating the historical information in the signal. Sophisticated signal analysis techniques such as the squared envelope spectrum and the spectral coherence are also used on the novel signal to highlight the bene ts of utilising the novel signal as opposed to raw vibration signal for fault diagnosis. Even though a healthy state is the desired operating condition of rotating machines, fault data will become available during the operational life of the machine. Therefore, a methodology, centred around discrepancy analysis, is developed to utilise the available historical fault data and to accommodate fault data becoming available during the operation of the machine. In this investigation, it is recognised that the machine condition monitoring problem is in fact an open set recognition problem with continuous transitions between the healthy machine condition and the failure conditions. This is explicitly incorporated into the methodology and used to infer the condition of the gearbox in an open set recognition framework. This methodology uses a di erent approach to the conventional supervised machine learning techniques found in the literature. The methodologies are investigated on numerical and experimental datasets generated under varying operating conditions. The results indicate the bene ts of incorporating prior knowledge into the fault diagnosis process: the fault diagnosis techniques can be more robust to varying operating conditions, more sensitive to damage and easier to interpret by a non-expert. In summary, fault diagnosis techniques are more e ective when prior knowledge is utilised.
Book Synopsis Proceedings of TEPEN 2022 by : Hao Zhang
Download or read book Proceedings of TEPEN 2022 written by Hao Zhang and published by Springer Nature. This book was released on 2023-03-03 with total page 1156 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume gathers the latest advances, innovations and applications in the field of efficiency and performance engineering, as presented by leading international researchers and engineers at the 2022 conference of the Efficiency and Performance Engineering Network (TEPEN), held in Beijing and Baotou, China on August 18-21, 2022. Topics include vibro-acoustics monitoring, condition-based maintenance, sensing and instrumentation, machine health monitoring, maintenance auditing and organization, non-destructive testing, reliability, asset management, condition monitoring, life-cycle cost optimisation, prognostics and health management, maintenance performance measurement, manufacturing process monitoring, and robot-based monitoring and diagnostics. The contributions, which were selected through a rigorous international peer-review process, share exciting ideas that will spur novel research directions and foster new multidisciplinary collaborations.
Book Synopsis Studies in Animal and Human Behaviour: Comparative studies of the motor patterns of anatinae (1941) by : Konrad Lorenz
Download or read book Studies in Animal and Human Behaviour: Comparative studies of the motor patterns of anatinae (1941) written by Konrad Lorenz and published by . This book was released on 1970 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Detailed Vibration Analysis of Pinion Gear with Time-Frequency Methods by : Marianne Mosher
Download or read book Detailed Vibration Analysis of Pinion Gear with Time-Frequency Methods written by Marianne Mosher and published by . This book was released on 2003 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Dynamics-guided Vibration Signal Analysis for Fixed-axis Gearbox Fault Diagnosis by : Xingkai Yang
Download or read book Dynamics-guided Vibration Signal Analysis for Fixed-axis Gearbox Fault Diagnosis written by Xingkai Yang and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gearboxes are key components commonly employed to transfer torque and power and adjust speed in mechatronic systems, such as wind turbines, automobiles, and mining machines. Due to the harsh working environment, various faults may occur in gearboxes. Tooth cracks account for a large proportion of gearbox faults. Detection and severity assessment of early tooth cracks is of vital significance to prevent gearbox failures since it enables efficient condition-based maintenance activities, which not only improves system reliability but also reduces operation and maintenance costs. Vibration analysis has been widely utilized for gear tooth crack detection and severity assessment. In industrial applications, gearboxes may work under either constant or time-varying operating conditions. Besides, gearboxes may suffer from either one single tooth crack or multiple tooth cracks depending on their working environment. All these factors render it challenging to get a good understanding of vibration characteristics of gearboxes with tooth cracks owing to their complexity, which undermines the effectiveness of vibration analysis for tooth crack detection and severity assessment. This thesis aims to procure some insights into vibration characteristics of fixed-axis spur gearboxes with tooth cracks through dynamic simulation, and the obtained insights are further adopted to guide the development of effective vibration signal analysis methods for tooth crack detection and severity assessment. To this end, the overarching objective of this thesis consists of four sub-objectives, which aim to address four issues related to tooth crack detection and severity assessment for fixed-axis spur gearboxes. Firstly, inspired by the observation that the Crack Induced Impulses (CII) contain more information on tooth crack growth, two novel condition indicators are developed by a proposed method which conducts a thorough analysis on the CII and are adopted for early tooth crack severity assessment. Secondly, to effectively track tooth crack severity progression under time-varying operating conditions, a comprehensive study on how time-varying operating conditions affect vibration signals of a fixed-axis spur gearbox with a tooth crack is conducted. A linear dependence of the Amplitude Modulation (AM) of the CII on the time-varying operating conditions is identified, through which a new condition indicator is proposed to track tooth crack severity progression under time-varying operating conditions. In addition, inspired by the finding that the AM of the CII is resulted from operating condition variations, a normalization method is proposed to remove the speed variation-induced AM of the CII and a normalized CII is obtained. The normalized CII preserve information on tooth crack growth and are free from gearbox speed fluctuations, which are used to track tooth crack severity progression under variable speed conditions. Lastly, insights into vibration characteristics of a fixed-axis spur gearbox with multiple tooth cracks are obtained using dynamic simulation and are further experimentally validated. Besides, inspired by the observation that the CII can well reflect tooth cracks, a method focusing on the CII is proposed to detect the number and locations of multiple tooth cracks in fixed-axis spur gearboxes. The research work conducted in this thesis enables us to procure a good understanding of vibration characteristics of fixed-axis spur gearboxes with tooth cracks working under both constant and time-varying operating conditions and provides effective vibration signal analysis methods for tooth crack detection and severity assessment of fixed-axis spur gearboxes. Future work will explore the effects of tooth lubrication and bearing faults on gearbox vibration characteristics.
Book Synopsis Vibration Based Planetary Gear Analysis and Damage Detection by : Rene Sawatzky
Download or read book Vibration Based Planetary Gear Analysis and Damage Detection written by Rene Sawatzky and published by . This book was released on 2014 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: With this thesis the research at the engineering department is continued, based on previous thesis projects. These projects were considering the possibility of simulation gears with rigid bodies. After researches with different emphasizes on the rigid body simulation, the gained knowledge showed limitations of the rigid body model. Gear failures are very diverse and the actual simulation technique could not represent all necessary failure modes that can occur. That led to this thesis as a research project to find a way to detect and analyze the failure modes that cannot be considered with the current rigid body approach. With the flexible body theory and simulation tools (MSC:Adams) this gap of gear failure detection simulation can be closed. The objective is, making it possible to simulate all failure modes of a gear that can occur. Additionally the previous project on this topic were using gears of small laboratory conditions. An industry sector has been picked to work on a practical application. This application is a wind turbine gearbox. These gearboxes have common run-time errors which influences the profitability of the power generation. To model this system a gear design guide for wind turbine gearboxes is elaborated.
Book Synopsis Condition Monitoring of Gear Systems Using Vibration Analysis by : Salem Al-Arbi
Download or read book Condition Monitoring of Gear Systems Using Vibration Analysis written by Salem Al-Arbi and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: It is often impractical to measure vibrations directly at /or close to their sources when condition monitoring gearbox systems. It is common to measure the vibration distant from the source due to limited access to the component which is to be monitored. In addition, operating the gearbox under different loads and speeds also produces vibration signals within different components. Vibration measured in this way may be significantly distorted by the effect of signal transmission paths and interference from other sources. Therefore, suppression of distortions is a key issue for remote measurement based condition monitoring. In this research work, the influences of transducer locations and operating conditions on the vibration signal have been investigated on a typical gearbox transmission system for the detection of faults induced within the gearbox. Vibration signals corresponding to a healthy (baseline) and faulty conditions on two-stage helical gearbox at various load and speed levels were recorded. The baseline vibration data were examined using conventional methods in the time, frequency and the joint time-frequency domains, and are referenced for comparison with more advanced methods. Several parameters have been proposed for monitoring gear condition locally (gearbox casing) including time, frequency, and joint time-frequency domain representation. The results show that traditional signal processing techniques were insufficient for revealing fault detection information due to the low signal to noise ratio (SNR). This research also presents a mathematical model for the simulation of vibration signals in order to further understand the source of the vibration. The model represents a two stage gear system using a suitable stiffness function to represent the forces acting between each pair of gears. Rotational stiffness and damping are also used to simulate the angular motion of the gears and shafts. Results show that the frequency spectrum of acceleration outputs from the model take the expected form with peaks at the meshing frequency and associated harmonics. Furthermore, if the stiffness function between the first pair of gears is simulated with a broken tooth, and various degrees of damage, outputs from the simulation have similar sideband effects to the signals produced in the experimental investigation. In addition, the model also demonstrates that variation of load and speed produces a corresponding effect to that seen in the experiments. Consequently, although relatively simple, the mathematical model can be used to explain vibration mechanisms in real gearbox systems used in condition monitoring. Time synchronous averaging (TSA) has been applied to the vibration signals from the gearbox to remove random noise combined with the raw signal. The angular domain signal, the order spectrum and the order-frequency presentation were used to characterise gearbox vibration in these new domains in more detail. Results obtained following TSA were compared with those obtained through conventional analysis from waveform characteristics, spectrum patterns and corresponding feature parameters under different operating loads and fault conditions. In addition, continuous wavelet transform (CWT) of TSA was also compared with the conventional CWT results of raw signals to further characterise vibrations. As part of this research study, the vibration transmission path has been estimated using the frequency response function (FRF) technique. A response based estimation method has been developed to revise the base path and adapted to operating conditions for more accurate fault estimation. Both theoretical analysis and test results showed that improved diagnosis when the path information was included in vibration signal processing and feature selection. Finally, the vibration data recorded from the two accelerometers located on the gearbox casing and motor flange were analyzed using different signal processing methods to investigate the effect of path transmission (transducer location) on the detection and diagnosis of the seeded gear tooth faults. Results from the angular domain, the order spectrum and the order-frequency analysis are presented to demonstrate use of these techniques for fault detection in gearboxes and that the effect of path transmissions can be observed on the vibration signals. Results showed that CWT of the TSA signal could be used to detect and indicate the severity of the gear damage effectively even if vibration signals originated from a remote motor flange.
