Eric Bechhoefer

Eric Bechhoefer
GPMS Inc

About

122
Publications
76,152
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,523
Citations

Publications

Publications (122)
Article
The wind power industry suffers from unexpectedly high failure rates in wind turbine high-speed shaft bearings (HSSBs). To reduce cost and improve availability, the industry needs an accurate fault prognostic and remaining useful life (RUL) capability. A reliable prognostic allows maintainers to better define when maintenance can be performed, impr...
Article
Full-text available
Mechanical faults in wind turbine generators lead to a huge problems of breaking electricity production, increase the maintenance cost and can damage the wind turbine generator, which caught fire in the nacelle. Gearbox installed in the nacelle is the important component in wind turbine, it composed by shafts bearings and gearings. Always bearings...
Conference Paper
Full-text available
Mechanical faults in wind turbine generators lead to a huge problems of breaking electricity production, increase the maintenance cost and can damage the wind turbine generator, which caught fire in the nacelle. Gearbox installed in the nacelle is the important component in wind turbine, it composed by shafts bearings and gearings. Always bearings...
Article
Full-text available
Condition monitoring of High-Speed Shaft Bearing (HSSB) in Wind Turbine Generators (WTGs) remains a challenging subject for industrial and academic studies. The investigation of mechanical vibration signals presents the most popular method in the literature. Consequently, this work involves a novel data-driven approach for direct HSSB prognosis usi...
Article
Full-text available
Operational readiness, reliability and safety are all enhanced through condition monitoring. That said, for many assets, there is still a need for a prognostic capability to calculate remaining useful life (RUL). RUL allows operation and maintenance personnel to better schedule assets, and logisticians to order long lead time part to help improve b...
Article
Full-text available
Wind power generating capacity was 239 GW at the end of 2011, with a further 46 GW of installed capacity to be operational by the end of 2012. While only providing 2.8% of the energy produce in the United States, its is anticipated that by 2030, fully 20% of the electrical energy will come from wind. This widespread deployment of industrial wind pr...
Article
Full-text available
WIND POWER generating capacity was 239 GW at the end of 2011, with a further 46 GW of installed capacity to be operational by the end of 2012. While only providing 2.8% of the energy produced in the United States, it is anticipated that by 2030, almost 20% of the total electrical energy will come from wind. This widespread deployment of industrial...
Article
Full-text available
State of health (SOH) condition monitoring of Lithium-ion (Li-ion) batteries is an important issue for safe and reliably operation of battery-powered products. Consequently, it remains a challenging subject for industrial and academic studies. In this paper, an incremental support vector regression (ISVR) is proposed for battery SOH lifetime estima...
Conference Paper
Full-text available
Mechanical failures in wind turbine generators cause many problems of stopping electricity production, increase the price of maintenance or the destruction of the wind turbine. The gearbox is the important component in wind turbine it composed by bearing and gearings, generally, failure appear in the bearing then in gearings. A probabilistic framew...
Conference Paper
Full-text available
Modern gear fault detection analysis began with algorithms based on the time synchronous average. Over the course of decades, many gear analyses have been proposed, but with no evidence that the analysis was significantly more powerful in terms of fault detection than existing algorithms. This study focuses on a comprehensive comparison of gear fau...
Article
Full-text available
Modern gear fault detection analysis began with algorithms based on the time synchronous average. Over the course of decades, many gear analyses have been proposed, but with no evidence that the analysis was significantly more powerful in terms of fault detection than existing algorithms. This study focuses on a comprehensive comparison of gear fau...
Conference Paper
Vibration signals are widely used in wind turbine drivetrain condition monitoring with the aim of fault detection, optimization of maintenance actions and therefore reduction of operating costs. Signals are most commonly sampled by accelerometers at high frequency for a few seconds. The behavior of these signals varies significantly, even within th...
Conference Paper
Full-text available
This paper is concerned with a nonlinear, computationally efficient method for trending component health. While conceptually simple, the goal of component trending is to reduce spurious noise in the measured component health and to estimate the remaining useful life (RUL). The need for lower computational effort allows this to be done on an embedde...
Conference Paper
Full-text available
During testing on a small gas turbine, frequencies related to the power turbine shaft and a bearing were observed. The frequencies of the fault were not associated with any known bearing on the power turbine shaft. This paper is an investigation of why the observed bearing fault frequency of 6% higher than anticipated. It will be shown that because...
Conference Paper
Full-text available
A cycloid drive for gearboxes allows for high reduction ratio and zero or very low backlash. The cycloid gear design is based on compression, whereas most gear interactions are based on shear. Further, the contract of a cycloid gear is typically subject to rolling forces vs. sliding, which are seen in traditional gearboxes. These features of a cycl...
Preprint
Full-text available
The big news here is that we finished the STC and installation on the Bell 407GX - this is a huge deal for us, as it allows us to sell and install kits. We just passed flight test. Dr. Eric Bechhoefer GPMS Inc.
Article
Full-text available
Because of the bandwidth limitation of the engine controller, all helicopter gearboxes change speed over time. This change in speed necessitates the resampling of the data, based on a tachometer signal, to facilitate shaft, gear and bearing analysis of the rotating equipment. Without resampling, the quality of vibration analysis is degraded, and ma...
Article
Full-text available
This paper presents a prognostic algorithm with low computational requirements that was implemented on an embedded system. The health of components such as shafts, bearings, and gears, is estimated based on a paradigm where condition indicators (CIs) are mapped into a health indicator (HI) for detecting and identifying faults based on vibration dat...
Article
Full-text available
Rotor Track and Balance (RTB) is a necessary maintenance action to improve aircraft ride quality and decrease fatigue for both the aircrew and helicopter equipment. While there have been a number of papers discussing the solution strategy for optimizing both blade track split and vibration, little work has been reported on how to calculate blade tr...
Article
This paper represents an integrated prognostics method dedicated to the wind turbine high-speed shaft bearing prognosis, which integrates physical degradation models and data driven approaches. In bearing failure prognostics, the excessive shaft vibration eventually leads to the system failure. In this case (crack growth prognostics), the measured...
Article
Full-text available
Planetary gearboxes are widely used in the drivetrain of wind turbines. Planetary gearbox fault diagnosis is very important for reducing the downtime and maintenance cost and improving the safety, reliability, and life span of the wind turbines. The wind energy industry is currently using condition monitoring systems to collect massive real-time da...
Article
The use of signal processing for condition monitoring of wind turbines data has been on-going since several decades. Failure in the analysis of high modulated data may make the machine break. An example of this is the reported real case of bearing failure on a Repower wind turbine, which could not be detected by currently applied methods. The machi...
Article
As a critical component, failures of high-speed shaft bearing in wind turbines cause the unplanned stoppage of electrical energy production. Investigations related to naturally progressed defects of high-speed shaft bearings are relatively scarce and the online assessment in damage severities is rarely available in the literature. In this sense, th...
Conference Paper
Full-text available
This paper represents an integrated prognostics method dedicated to the wind turbine high-speed shaft bearing prognosis, which integrates physical degradation model and data driven approaches. Indeed, we introduce an integrated prognostic approach based on usage model through Paris's law and the use of a Kalman smoother to estimate the remaining us...
Conference Paper
Track degradation of wind turbine high-speed shaft bearing can reduce unscheduled maintenance events, and safe power generation system. This paper proposes a particle filter-based prognostic approach for high-speed shaft bearing track degradation; this approach is validated by inspecting a real data from a wind turbine drivetrain. The particle filt...
Article
Full-text available
Bearings are typically used in wind turbines to support shafts and gears that increase rotational speed from a low speed rotor to a higher speed electrical generator. For various bearing applications, condition monitoring using vibration measurements has remained a subject of intense study to the present day since several decades. Various signal pr...
Article
Full-text available
Helicopter Flight Data Monitoring (HFDM) can be a central and very effective component of an operator's safety management system. By capturing operational information about aircraft operations, the operator/owner can identify safety hazards, facilitate monitoring and assessment of the interaction between the pilot and the aircraft, initiate remedia...
Article
Full-text available
In this research, we review condition-monitoring technologies for offshore steel wire ropes (SWR). Such ropes are used within several offshore applications including cranes for load handling such as subsea construction at depths up to 3-4000 meters, drilling lines, marine riser tensioner lines and anchor lines. For mooring, there is a clear tendenc...
Conference Paper
Full-text available
In the age of Internet of Things and Industrial 4.0, the prognostic and health management (PHM) systems are used to collect massive real-time data from mechanical equipment. Mechanical big data has the characteristics of large-volume, diversity and high-velocity. Effectively mining features from such data and accurately identifying the machinery he...
Article
Full-text available
A critical work of bearing fault diagnosis is locating the optimum frequency band that contains faulty bearing signal, which is usually buried in the noise background. Now, envelope analysis is commonly used to obtain the bearing defect harmonics from the envelope signal spectrum analysis and has shown fine results in identifying incipient failures...
Article
Full-text available
Large, slow turning bearings remain difficult to analyze for diagnostics and prognostics. This poses a critical problem for high value assets, such as drilling equipment top drives, mining equipment, wind turbine main rotors, and helicopter swash plates. An undetected bearing fault can disrupt service, and cause delays, lost productivity, or accide...
Conference Paper
Full-text available
Premature failures of wind turbine gearboxes increase the cost of energy and affect their reliability. Most gearbox failures initiate in bearings. High-speed bearings and planetary bearings exhibit a high rate of premature failure. A critical work of bearing fault diagnosis is locating the optimum frequency band that contains faulty bearing signal,...
Article
Full-text available
In this paper, we develop an integrated prognostics method considering a time-varying operating condition, which integrates physical gear models and sensor data. By taking advantage of stress analysis in finite element modeling (FEM), the degradation process governed by Paris’ law can adjust itself immediately to respond to the changes of the opera...
Conference Paper
Full-text available
The ability to prognosticate the future state of a mechanical component can greatly improve the ability of a helicopter operator to manage their assets. Fundamentally, prognostics can change the logistics support of a helicopter by: reducing spares, improving the likelihood of a deployment meeting its mission requirements, and reducing unscheduled...
Article
Full-text available
The ability to prognosticate the future state of a mechanical component can greatly improve the ability of a helicopter operator to manage their assets. Fundamentally, prognostics can change the logistics support of a helicopter by: reducing spares, improving the likelihood of a deployment meeting its mission requirements, and reducing unscheduled...
Article
Full-text available
Vibration analysis algorithms for shaft and gear faults are predominately based on the time synchronous average (TSA). The TSA resamples the vibration data over one shaft revolution, and averages that data over the number of revolutions associated with the acquisition. This has the effect of improving Fourier analysis for that shaft (no spectral sm...
Article
Full-text available
Vibration analysis algorithms for shaft and gear faults are predominately based on the time synchronous average (TSA). The TSA resamples the vibration data over one shaft revolution, and averages that data over the number of revolutions associated with the acquisition. This has the effect of improving Fourier analysis for that shaft (no spectral sm...
Article
Full-text available
Planetary gearboxes (PGBs) are widely used in the drivetrain of wind turbines. Any PGB failure could lead to a significant breakdown or major loss of a wind turbine. Therefore, PGB fault diagnosis is very important for reducing the downtime and maintenance cost and improving the safety, reliability, and lifespan of wind turbines. The wind energy in...
Article
Full-text available
In the condition based maintenance work of rotating machineries, bearings’ fault diagnosis and prognosis are an important content. Their faults can lead to many disasters. So, to detect the bearing faults earlier can benefit the remaining useful life (RUL) prediction and maintenance actions. In order to achieve this goal, narrowband interference ca...
Conference Paper
Full-text available
Planetary gearboxes are widely used in the drivetrain of helicopters and wind turbines. Any planetary gearbox failure could lead to breakdown of the whole drivetrain and major loss of helicopters and wind turbines. Therefore, planetary gearbox fault diagnosis is an important topic in PHM. Planetary gearbox fault diagnosis has been done mostly throu...
Article
Full-text available
The diagnosis of bearing health through the quantification of accelerometer data has been an area of interest for many years and has resulted in numerous signal processing methods and algorithms. This paper proposes a new diagnostic approach that combines envelope analysis, time synchronous resampling, and spectral averaging of vibration signals to...
Article
Condition-based maintenance (CBM) has become a hot research topic in recent decades. For enhancing the CBM ability, many researchers pay attention to the incipient fault detection and remaining useful life (RUL) prediction. Detecting faults earlier can provide enough lead time to manage the maintenance actions. Besides of this, predicting RUL more...
Article
Full-text available
The widespread deployment of industrial wind projects will require a more proactive maintenance strategy in order to be more cost competitive. This paper describes an ongoing research project on developing online lubrication oil condition monitoring and degradation detection tools using commercially available online sensors. In particular, an inves...
Patent
Full-text available
Described are techniques for selecting options used with current sensor data characterizing vibration caused by rotating blades. Sets of other sensor data are evaluated to determine a first of the sets of other sensor data that is a best match for said current sensor data. Each of the sets of other sensor data is associated with one of a plurality...
Article
Full-text available
In recent years, acoustic emission (AE) sensors and AE-based techniques have been developed and tested for gearbox fault diagnosis. In general, AE-based techniques require much higher sampling rates than vibration analysis-based techniques for gearbox fault diagnosis. Therefore, it is questionable whether an AE-based technique would give a better o...
Article
Full-text available
Robust features are very critical to track the degradation process of a gear. They are key factors for implementing fault diagnosis and prognosis. This has driven the need in research for extracting good features. This paper used a new method, Narrowband Interference Cancellation, to suppress the narrow band component and enhance the impulsive comp...
Article
Full-text available
The diagnosis of bearing health through the quantification of accelerometer data has been an area of interest for many years and has resulted in numerous signal processing methods and algorithms. In this paper, a new bearing fault diagnostic approach that combines envelope analysis, time synchronous resampling, and spectral averaging of vibration s...
Article
Full-text available
In recent years, acoustic emission (AE) sensors and AE based techniques have been developed and tested for gearbox fault diagnosis. In general, AE based techniques require much higher sampling rate than vibration analysis based techniques for gearbox fault diagnosis. Therefore, it is questionable if an AE based technique would give a better or at l...
Article
Full-text available
Vibration derived from the main rotor dynamics and imbalance causes premature wear to the aircraft components, and can cause pilot fatigue. While improvements have been made in rotor track and balance (RTB) techniques; there is room to enhance the quality of the recommended RTB adjustments. One aspect that limits the development of RTB algorithms i...
Article
Full-text available
There is no established threshold or limit for gear vibration based condition indicators (CI) that indicates when a gear is in need of maintenance. The best we can do is set CI thresholds statistically, based on some small probability of false alarm. Further, to the best of our knowledge, there is no single CI that is sensitive to every failure mod...
Article
The development of enhanced fault detection ability for gearbox systems has received considerable attention in recent years. Detecting the gear fault easier is very important for maintenance action. This has driven the need in research for enhanced gear fault detection method. The goal is to extract periodic impulse signal from the very noise signa...
Article
Full-text available
In order to reduce the costs of wind energy, it is necessary to improve the wind turbine availability and reduce the operational and maintenance costs. The reliability and availability of a functioning wind turbine depend largely on the protective properties of the lubrication oil for its drive train subassemblies such as gearbox and means for lubr...
Conference Paper
Full-text available
To increase wind energy production rate, there is a pressing need to improve the wind turbine availability and reduce the operational and maintenance costs. The safety and reliability of a functioning wind turbine depend largely on the protective properties of the lubrication oil for its drive train subassemblies such as gearbox and means for lubri...
Conference Paper
Full-text available
Acoustic emission (AE) has been studied as a potential information source for machine fault diagnosis for a long time. However, AE sensors have not yet been applied widely in real applications. Firstly, in comparison with other sensors such as vibration, AE sensors require much higher sampling rate. The characteristic frequency of AE signals genera...
Patent
Full-text available
Determining health of a component includes using at least one processor to perform processes including acquiring a plurality of measured values corresponding to the condition indicators. Synchronous noise components are removed from the measured values to provide revised measured values, and the revised measured values are used to determine noise-f...
Patent
Full-text available
In vibration based mechanical diagnostics, algorithms may extract some feature of a component which may be used as a statistic of the components' health. A measured condition indicator corresponding to the analysis of the components' health may be a function of transmission error (TE). Because there exists a relationship between TE and the CI for a...
Article
Full-text available
Acoustic Emission (AE) sensors have been investigated as a potential tool for machinery health monitoring and fault diagnostics. While AE sensors could possibly provide higher fault detection sensitivity compared with vibration sensors, they also have some drawbacks. AE sensors generally output signals in the range of several hundred kHz up to seve...
Article
Full-text available
Recently, an increasing demand for performance assessment of lubrication oil has been noticed. Considerable techniques and systems in lubrication oil condition monitoring have been developed and successfully utilized in many applications such as gasoline/diesel engines, gearboxes, etc. This paper provides a comprehensive review of the existing lubr...
Article
Acoustic emission (AE) has been studied as a potential information source for machine fault diagnosis for a long time. However, AE based techniques have not yet been applied widely in real health and usage monitoring system (HUMS) applications because of the difficulties and costs associated with AE data analysis. First of all, in comparison with o...
Article
Full-text available
Acoustic Emissions (AE) are stress waves produced by the sudden internal stress redistribution of material caused by changes in the internal structure of the material. Possible causes of these changes are crack initiation and growth, crack opening/closure, or pitting in monolithic materials (gear/ bearing material). Where as vibration can measure t...