Data processing: measuring – calibrating – or testing – Measurement system in a specific environment – Mechanical measurement system
Reexamination Certificate
2001-12-04
2003-11-18
Barlow, John (Department: 2863)
Data processing: measuring, calibrating, or testing
Measurement system in a specific environment
Mechanical measurement system
C702S190000, C701S300000, C382S103000, C455S431000
Reexamination Certificate
active
06651012
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This application relates to the field of vibration analysis and more particularly to performing vibration analysis for the purpose of device monitoring.
2. Description of Related Art
The transmission of power to rotors which propel helicopters and other shafts that propel devices within the aircraft induce vibrations in the supporting structure. The vibrations occur at frequencies that correspond to the shaft rotation rate, mesh rate, bearing passing frequency, and harmonics thereof. The vibration is associated with transmission error (TE). Increased levels of TE are associated with transmission failure. Similar types of vibrations are produced by transmissions in fixed installations as well.
Parts, such as those that may be included in a helicopter transmission, may be replaced in accordance with a predetermined maintenance and parts replacement schedule. These schedules provide for replacement of parts prior to failure. The replacement schedules may indicate replacement time intervals that are too aggressive resulting in needless replacement of working parts. This may result in incurring unnecessary costs as airplane parts are expensive. Additionally, new equipment may have installed faulty or defective parts that may fail prematurely.
Thus it may be desirable to provide for an efficient technique for detecting part and device degradation without unnecessarily replacing parts. It may be desirable that this technique also provide for problem determination and detection prior to failure.
SUMMARY OF THE INVENTION
In accordance with one aspect of the invention are a method executed in a computer system and a computer program product for determining an health indicator of a component at a subsequent time. A first health indicator of said component at a time, n, is determined in accordance with at least one corresponding condition indicator. A second health indicator of the component is determined using a three state Kalman filter at a time subsequent to time n.
REFERENCES:
patent: 5911127 (1999-06-01), Tulpule
patent: 5937349 (1999-08-01), Andresen
patent: 5960097 (1999-09-01), Pfeiffer et al.
patent: 6014652 (2000-01-01), Hill et al.
patent: 6292752 (2001-09-01), Franke et al.
patent: 42 07 728 (1993-09-01), None
patent: WO 99/54703 (1999-10-01), None
Jarque-bera test of normality: Judge, G. G., R.C. Hill, W.E., Griffiths, H. Lutkepohl, and T.-C. Lee. “Introduction to the Theory and Practice of Econometrics”, New York, Wiley.
Lilliefors test of normality: Conover, W.J., “Practical Nonparametric Statistics”, New York, Wiley, 1980.
Kolmogorov-smirniv goodness of fit: Kolmogorov, A.N., “Sulla Determinazoine empirica di una legge di distribuzione”, Giorn dell'Inst. Ital. degli. Att., 4, 89-91, 1933.
Chi squared: Sheskin, D.J., “Handbook of Parametric and Nonparametric Statistical Procedures”, CRC Press, Boca Raton, FL, 1997.
Fukunaga, Keinosuke, Academic Press, “Hypothesis Testing”, Introduction to Statistical Pattern Recognition, 51-97, 1990.
VanTress, Harry, John Wiley & Sons, Inc., “The General Gaussian Problem”, Detection, Estimation and Modulation Theory, Part 1, 96-117, 1968.
Mendenhall, Wackerly and Scheaffer, “The Chi-Square Test”, Mathematical Statistics with Application, 642-647, 1990.
Smith, J. Derek, Marcel Dekker, Inc., “Causes of Noise”, Gear Noise and Vibration, 3-63, 1999.
Hochmann, et al., “Mechanics of Gear Tooth Crack Signals and their Detection in Application for a Helicopter Health Usage and Management System (HUMS)”, Goodrich Company, 1-12, 2002.
“Eigenvalues and Eigenvectors”, 244-253.
Numerical Recipes In C: The Art of Scientific Computing, “14.3 Are Two Distributions Different?” by Cambridge University Press, 1988-1992, pp. 620-628.
Mitchell, John, Introduction to Machinery Analysis and Monitoring 2ndEdition, “Analyzing Machine Condition-General Characteristics”, Pennwell Books, 1993, pp. 171-255.
Barlow John
Bhat Aditya
Simmonds Precision Products Inc.
LandOfFree
Method and apparatus for trending and predicting the health... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for trending and predicting the health..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for trending and predicting the health... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3137813