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Condition Monitoring Of Helicopter Gearboxes Using Automatic Vibration Analysis Techniques
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Book Synopsis Condition Monitoring of Helicopter Gearboxes Using Automatic Vibration Analysis Techniques by : P. Gadd
Download or read book Condition Monitoring of Helicopter Gearboxes Using Automatic Vibration Analysis Techniques written by P. Gadd and published by . This book was released on 1985 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper describes work carried out in the Fleet Air Arm to develop and prove the gearbox vibration techniques involved. Arrangements for data collection in flight and during ground runs are described. The signal processing methods, including the automatic techniques for secondary analysis which enable defined features to be extracted from the basic signatures, are discussed. Examples are given of the extent to which damage or malfunction of various internal components can be discerned by the techniques employed. The question of application to the widely dispersed fleet of naval aircraft is considered, and the prospects for achieving full on-condition maintenance of in-service gearboxes is assessed.
Book Synopsis Advances in Computer Vision and Information Technology by :
Download or read book Advances in Computer Vision and Information Technology written by and published by I. K. International Pvt Ltd. This book was released on 2013-12-30 with total page 1688 pages. Available in PDF, EPUB and Kindle. Book excerpt: The latest trends in information technology represent a new intellectual paradigm for scientific exploration and the visualization of scientific phenomena. This title covers the emerging technologies in the field. Academics, engineers, industrialists, scientists and researchers engaged in teaching, and research and development of computer science and information technology will find the book useful for their academic and research work.
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.
Book Synopsis Condition Monitoring of Gearboxes by Vibration Analysis by : S. B. Glavatskikh
Download or read book Condition Monitoring of Gearboxes by Vibration Analysis written by S. B. Glavatskikh and published by . This book was released on 1995 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Vibration-based Condition Monitoring by : Robert Bond Randall
Download or read book Vibration-based Condition Monitoring written by Robert Bond Randall and published by John Wiley & Sons. This book was released on 2011-03-25 with total page 409 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Without doubt the best modern and up-to-date text on the topic, wirtten by one of the world leading experts in the field. Should be on the desk of any practitioner or researcher involved in the field of Machine Condition Monitoring" Simon Braun, Israel Institute of Technology Explaining complex ideas in an easy to understand way, Vibration-based Condition Monitoring provides a comprehensive survey of the application of vibration analysis to the condition monitoring of machines. Reflecting the natural progression of these systems by presenting the fundamental material and then moving onto detection, diagnosis and prognosis, Randall presents classic and state-of-the-art research results that cover vibration signals from rotating and reciprocating machines; basic signal processing techniques; fault detection; diagnostic techniques, and prognostics. Developed out of notes for a course in machine condition monitoring given by Robert Bond Randall over ten years at the University of New South Wales, Vibration-based Condition Monitoring: Industrial, Aerospace and Automotive Applications is essential reading for graduate and postgraduate students/ researchers in machine condition monitoring and diagnostics as well as condition monitoring practitioners and machine manufacturers who want to include a machine monitoring service with their product. Includes a number of exercises for each chapter, many based on Matlab, to illustrate basic points as well as to facilitate the use of the book as a textbook for courses in the topic. Accompanied by a website www.wiley.com/go/randall housing exercises along with data sets and implementation code in Matlab for some of the methods as well as other pedagogical aids. Authored by an internationally recognised authority in the area of condition monitoring.
Download or read book The Shock and Vibration Digest written by and published by . This book was released on 1986 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Scientific and Technical Aerospace Reports by :
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Vibration Monitoring, Testing, and Instrumentation by : Clarence W. de Silva
Download or read book Vibration Monitoring, Testing, and Instrumentation written by Clarence W. de Silva and published by CRC Press. This book was released on 2007-04-19 with total page 698 pages. Available in PDF, EPUB and Kindle. Book excerpt: Controlling a system's vibrational behavior, whether for reducing harmful vibrations or for enhancing useful types, is critical to ensure safe and economical operation as well as longer structural and equipment lifetimes. A related issue is the effect of vibration on humans and their environment. Achieving control of vibration requires thorough und
Book Synopsis Interpolation Techniques for the Time Domain Averaging of Vibration Data with Application to Helicopter Gearbox Monitoring by : P. D. McFadden
Download or read book Interpolation Techniques for the Time Domain Averaging of Vibration Data with Application to Helicopter Gearbox Monitoring written by P. D. McFadden and published by . This book was released on 1986 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interpolation techniques provide an alternative to the phase-locked frequency multiplier for the calculation of the time domain average of a vibration signal. Higher order interpolation techniques produce flatter passbands and lower sidelobes in the stopband but require longer calculation times. Aliasing errors are introduced into the result by replication of the sidelobes during interpolation. In general, the errors are attenuated by time domain averaging, but under some conditions may be passed without attenuation. Keywords: Gear boxes, Helicopter, Signal averaging, Condition monitoring, Australia.
Download or read book Ordnance written by and published by . This book was released on 1990 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Proposal for Modifications to the Wessex Helicopter Main Rotor Gearbox Vibration Monitoring Program by : P. D. McFadden
Download or read book Proposal for Modifications to the Wessex Helicopter Main Rotor Gearbox Vibration Monitoring Program written by P. D. McFadden and published by . This book was released on 1985 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modifications to the RAN Recorded Tape Vibration Analysis Program for the condition monitoring of the main rotor gearbox in the Wessex helicopter are proposed to take advantage of recent developments in the techniques of signal averaging and computer enhancement of vibration data. Keywords: phase locked systems; input; equipment requirements; cost estimates. (Author).
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 Condition Monitoring '91 by : Mervin H. Jones
Download or read book Condition Monitoring '91 written by Mervin H. Jones and published by . This book was released on 1991 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: Programme covered management programmes, user experience, instrumentation and novel techniques.
Book Synopsis Reliability and Statistics in Transportation and Communication by : Igor Kabashkin
Download or read book Reliability and Statistics in Transportation and Communication written by Igor Kabashkin and published by Springer. This book was released on 2019-03-09 with total page 821 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reports on cutting-edge theories and methods for analyzing complex systems, such as transportation and communication networks and discusses multi-disciplinary approaches to dependability problems encountered when dealing with complex systems in practice. The book presents the most noteworthy methods and results discussed at the International Conference on Reliability and Statistics in Transportation and Communication (RelStat), which took place in Riga, Latvia on October 17 – 20, 2018. It spans a broad spectrum of topics, from mathematical models and design methodologies, to software engineering, data security and financial issues, as well as practical problems in technical systems, such as transportation and telecommunications, and in engineering education.
Book Synopsis Condition Monitoring and Nonlinear Frequency Analysis Based Fault Detection of Mechanical Vibration Systems by : Hogir Rafiq
Download or read book Condition Monitoring and Nonlinear Frequency Analysis Based Fault Detection of Mechanical Vibration Systems written by Hogir Rafiq and published by Springer Nature. This book was released on 2023-08-26 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hogir Rafiq proposes two approaches, the signal processing based condition monitoring approaches with applications to fault detection in gear systems, and application of deep mathematical and system theoretical methods to fault detection. The author develops the multivariate empirical mode decomposition (MEMD) algorithm to enhance the capability of extracting fault features and theoretical problems in nonlinear frequency analysis methods, respectively. The effectiveness has been demonstrated by an experimental study on a wind turbine gearbox test rig.
Book Synopsis Condition Monitoring of Gearboxes Operating Under Fluctuating Load Conditions by : Cornelius Johannes Stander
Download or read book Condition Monitoring of Gearboxes Operating Under Fluctuating Load Conditions written by Cornelius Johannes Stander and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Conventional gearbox vibration monitoring techniques are based on the assumption that changes in the measured structural response are caused by deterioration in the condition of the gears in the gearbox. However, this assumption is not valid under fluctuating load conditions, since the fluctuating load will amplitude modulate the measured vibration signal and cause the rotational speed of the system to change. In general monitoring of machines subject to fluctuating load conditions is dealt with by considering the constant load conditions on gearboxes or during free rotational tests. The need to monitor the condition of large gearboxes in mineral mining equipment has attracted greater interest in order to improve asset management. An inherent need for signal processing techniques, with the ability to indicate degradation in gear condition, under fluctuating load conditions exist. Such techniques should enable the online monitoring of gearboxes that operate under fluctuating load conditions. A continued flow of up to date information should consequently be available for asset and production management. With this research, a load demodulation normalisation procedure was developed to remove the modulation caused by fluctuating load conditions, which obscures the detection of an incipient gear fault conditions. A rotation domain averaging technique is implemented which combines the ability of computer order tracking and time domain averaging to suppress the spectral smearing effect caused by the fluctuation in speed, as well as to suppress the amplitude of the vibration which is not synchronous with the rotation of the gear shaft. It is demonstrated that the instantaneous angular speed of a gearbox shaft can be utilised to monitor the condition of the gear on the shaft. The instantaneous angular speed response measurement is less susceptible to phase distortion introduced by the transmission path when compared to conventional gearbox casing vibration measurements. A phase domain averaging approach was developed to overcome the phase distortion effect of the transmission path under fluctuating load conditions. The load demodulation normalisation and rotation domain averaging signal processing procedures were applied to both the conventional gearbox casing vibration and instantaneous angular speed measurements prior to the calculation of a smoothed pseudo Wigner-Ville distribution of the data. Statistical parameters such as the energy ratio were calculated from the distribution. These parameters could be monotonically trended under different load conditions to indicate the degradation of gear conditions.
Download or read book NASA SP. written by and published by . This book was released on 1990 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt:
