Download or read book An Investigation of Gear Mesh Failure Prediction Techniques written by and published by DIANE Publishing. This book was released on with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An investigation of gear mesh failure prediction techniques written by James J. Zakrajsek and published by . This book was released on 1989 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of Gear Failure Detection Methods written by John L. Frarey and published by . This book was released on 1970 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the program was to develop detection methods and to test the capability of these methods to provide information on the mechanical failures of gearing systems. Gear wear was the failure mechanism selected for this first phase of this effort. An analytical method was used to predict the amplitude ratios of the first three harmonics of the gear mesh vibrational frequencies as a function of tip wear in a set of test gears. These gears were then operated and the amplitude ratios were measured using a detector. Reasonably good correlation between predicted and measured values was obtained for the 3/1 ratio. Poor correlation was obtained for 2/1 ratio. This technique shows promise as a method of monitoring gear wear. (Author).
Download or read book Rotating Machinery Structural Health Monitoring Shock and Vibration Volume 5 written by Tom Proulx and published by Springer. This book was released on 2011-03-22 with total page 554 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rotating Machinery, Structural Health Monitoring, Shock and Vibration, Volume 5 Proceedings of the 29th IMAC, A Conference and Exposition on Structural Dynamics, 2011, the fifth volume of six from the Conference, brings together 35 contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Rotating Machinery, Structural Health Monitoring, as well as Shock and Vibration, along with other structural engineering areas.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Consideration of Moving Tooth Load in Gear Crack Propagation Predictions written by and published by . This book was released on 2000 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Robust gear designs consider not only crack initiation, but crack propagation trajectories for a fail-safe design. In actual gear operation, the magnitude as well as the position of the force changes as the gear rotates through the mesh. A study to determine the effect of moving gear tooth load on crack propagation predictions was performed. Two dimensional analysis of an involuted spur gear and three-dimensional analysis of a spiral-bevel pinion gear using the finite element method and boundary element method were studied and compared to experiments. A modified theory for predicting gear crack propagation paths based on the criteria of Erdogan and Sih was investigated. Crack simulation based on calculated stress intensity factors and mixed mode crack angle prediction techniques using a simple static analysis in which the tooth load was located at the highest point of single tooth contact was validated. For three-dimensional analysis, however, the analysis was valid only as long as the crack did not approach the contact region on the tooth.
Download or read book Crack Detection for Aerospace Quality Spur Gears written by and published by . This book was released on 2002 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Health and Usage Monitoring System research and development involves analysis of the vibration signals produced by a gearbox throughout its life. There are two major advantages of knowing the actual lifetime of a gearbox component: safety and cost. In this report, a technique is proposed to help extract the critical data and present it in a manner that can be easy to understand. The key feature of the technique is to make it independent of speed, torque and prior history for localized, single tooth damage such as gear cracks. This extraction technique is demonstrated on two sets of digitized vibration data from cracked spur gears. Standard vibration diagnostic parameters are calculated and presented for comparison. Several new detection algorithms are also presented. The results of this study indicate that crack detection methods examined are not robust or repeatable. The proposed techniques provide a limited improvement to existing diagnostic parameters. Current techniques show that the cracks progressed at a much faster rate than anticipated which reduced available time for detection.
Download or read book Handbook of Multisensor Data Fusion written by Martin Liggins II and published by CRC Press. This book was released on 2017-01-06 with total page 872 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the years since the bestselling first edition, fusion research and applications have adapted to service-oriented architectures and pushed the boundaries of situational modeling in human behavior, expanding into fields such as chemical and biological sensing, crisis management, and intelligent buildings. Handbook of Multisensor Data Fusion: Theory and Practice, Second Edition represents the most current concepts and theory as information fusion expands into the realm of network-centric architectures. It reflects new developments in distributed and detection fusion, situation and impact awareness in complex applications, and human cognitive concepts. With contributions from the world’s leading fusion experts, this second edition expands to 31 chapters covering the fundamental theory and cutting-edge developments that are driving this field. New to the Second Edition— · Applications in electromagnetic systems and chemical and biological sensors · Army command and combat identification techniques · Techniques for automated reasoning · Advances in Kalman filtering · Fusion in a network centric environment · Service-oriented architecture concepts · Intelligent agents for improved decision making · Commercial off-the-shelf (COTS) software tools From basic information to state-of-the-art theories, this second edition continues to be a unique, comprehensive, and up-to-date resource for data fusion systems designers.
Download or read book Bibliography of Lewis Research Center Technical Publications Announced in 1990 written by and published by . This book was released on 1991 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects on Diagnostic Parameters After Removing Additional Synchronous Gear Meshes written by and published by . This book was released on 2003 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gear cracks are typically difficult to diagnose with sufficient time before catastrophic damage occurs. Significant damage must be present before algorithms appear to be able to detect the damage. Frequently there are multiple gear meshes on a single shaft. Since they are all synchronous with the shaft frequency, the commonly used synchronous averaging technique is ineffective in removing other gear mesh effects. Carefully applying a filter to these extraneous gear mesh frequencies can reduce the overall vibration signal and increase the accuracy of commonly used vibration metrics. The vibration signals from three seeded fault tests were analyzed using this filtering procedure. Both the filtered and unfiltered vibration signals were then analyzed using commonly used fault detection metrics and compared. The tests were conducted on aerospace quality spur gears in a test rig. The tests were conducted at speeds ranging from 2500 to 5000 revolutions per minute and torques from 184 to 228 percent of design load. The inability to detect these cracks with high confidence results from the high loading which is causing fast fracture as opposed to stable crack growth. The results indicate that these techniques do not currently produce an indication of damage that significantly exceeds experimental scatter.
Download or read book 30th AIAA ASME SAE ASEE Joint Propulsion Conference written by and published by . This book was released on 1994 with total page 638 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of a Model Based Technique for Gear Diagnostics Using the Wigner Ville Method written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-17 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Imperfections in gear tooth geometry often result from errors in the manufacturing process or excessive material wear during operation. Such faults in the gear tooth geometry can result in large vibrations in the transmission system, and, in some cases, may lead to early failure of the gear transmission system. This report presents the study of the effects of imperfection in gear tooth geometry on the dynamic characteristics of a gear transmission system. The faults in the gear tooth geometry are modeled numerically as the deviation of the tooth profile from its original involute geometry. The changes in gear mesh stiffness due to various profile and pattern variations are evaluated numerically. The resulting changes in the mesh stiffness are incorporated into a computer code to simulate the dynamics of the gear transmission system. A parametric study is performed to examine the sensitivity of gear tooth geometry imperfections on the vibration of a gear transmission system. The parameters variations in this study consist of the magnitude of the imperfection, the pattern of the profile variation, and the total number of teeth affected. Numerical results from the dynamic simulations are examined in both the time and the frequency domains. A joint time-frequency analysis procedure using the Wigner-Ville Distribution is also introduced to identify the location of the damaged tooth from the vibration signature. Numerical simulations of the system dynamics with gear faults were compared to experimental results. An optimal tracker was introduced to quantify the level of damage in the gear mesh system. Conclusions are drawn from the results of this numerical study. Choy, F. and Xu, A. and Polyshchuk, V. Glenn Research Center GEARS; GEAR TEETH; DYNAMIC CHARACTERISTICS; DEFECTS; MATHEMATICAL MODELS; TRANSMISSIONS (MACHINE ELEMENTS); FAULT DETECTION; GEOMETRIC ACCURACY; STIFFNESS; TIME DEPENDENCE; FREQUENCIES; SYSTEMS HEALTH MONITORING; VIBRATION EFFECTS...
Download or read book Vibration Problems ICOVP 2011 the 10th International Conference on Vibration Problems written by and published by ICOVP 2011 Supplement. This book was released on 2011 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Multisensor Data Fusion written by David Hall and published by CRC Press. This book was released on 2001-06-20 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: The emerging technology of multisensor data fusion has a wide range of applications, both in Department of Defense (DoD) areas and in the civilian arena. The techniques of multisensor data fusion draw from an equally broad range of disciplines, including artificial intelligence, pattern recognition, and statistical estimation. With the rapid evolut
Download or read book Systematic Analysis of Gear Failures written by Lester E. Alban and published by ASM International. This book was released on 1985-01-01 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explores the detailed steps necessary to determine the causes of failure. First, the physical characteristics of a gear are studied: where the stress points are, from what directions the forces are applied, where the movement of material progresses, and where strain patterns exist. Second, all external conditions and forces are considered. With this background information, a systematic examination is described from beginning to end, the end being a conclusion about the mode and cause of failure.
Download or read book Evaluation of a Vibration Diagnostic System for the Detection of Spur Gear Pitting Failures written by Dennis P. Townsend and published by . This book was released on 1993 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Examination of a Technique for the Early Detection of Failure in Gears by Signal Processing of the Time Domain Average of the Meshing Vibration written by P. D. McFadden and published by . This book was released on 1986 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: An existing technique for the signal processing to the time domain average of the tooth meshing vibration of gears is examined with application to the early detection of failure. It is shown that the regular signal extracted from the time domain average of the gear vibration by the elimination of the fundamental and harmonics of the tooth meshing frequency forms the time domain average of the vibration of a single tooth. The residual signal which is obtained by subtracting the regular signal from the original time domain average gives the departures of the vibration from the average. Numerical and practical examples are given. (Author).
