Claims
- 1. An apparatus for detecting a hot rail car surface comprising:
an infrared sensor for acquiring an infrared signal from a rail car surface of a rail car and transducing said infrared signal into an electrical signal; a rank filter for filtering said electrical signal to produce a filtered array; a first peak detector for detecting a maximum filtered value of said filtered array; and a first comparator for comparing said maximum filtered value to a detection threshold to produce a filtered alarm signal.
- 2. The apparatus of claim 1 wherein said rank filter has a rank of about one-half.
- 3. The apparatus of claim 1 further comprising:
a wireless transceiver for acquiring rail car surface characteristics from a wireless tag mounted on said rail car; and a filter parameter calculator for calculating a filter length and rank of said rank filter as a function of said rail car surface characteristics.
- 4. The apparatus of claim 1 further comprising:
an unfiltered signal buffer for buffering said electrical signal to produce an unfiltered array; a second peak detector for detecting a maximum unfiltered value of said unfiltered array; a second comparator for comparing said maximum unfiltered value to said detection threshold to produce an unfiltered alarm signal; and an alarm comparator for comparing said unfiltered alarm signal to said filtered alarm signal to produce a censored false alarm signal.
- 5. The apparatus of the previous claim wherein:
said censored false alarm signal comprises a binary signal having a true value when said unfiltered alarm signal differs from said filtered alarm signal and a false value otherwise; and said apparatus further comprises a counter for counting said false values to produce a censored false alarm count.
- 6. The apparatus of the previous claim further comprising a failure isolator for diagnosing a failure mode from said censored false alarm count.
- 7. An apparatus for detecting a hot rail car surface comprising:
an infrared sensor for acquiring an infrared signal from a rail car surface of a rail car and transducing said infrared signal into an electrical signal; a rank filter for filtering said electrical signal to produce a filtered array; a first peak detector for detecting a maximum filtered value of said filtered array; a first comparator for comparing said maximum filtered value to a detection threshold to produce a filtered alarm signal; a wireless transceiver for acquiring rail car surface characteristics from a wireless tag mounted on said rail car; a filter parameter calculator for calculating a filter length and rank of said rank filter as a function of said rail car surface characteristics; an unfiltered signal buffer for buffering said electrical signal to produce an unfiltered array; a second peak detector for detecting a maximum unfiltered value of said unfiltered array; a second comparator for comparing said maximum unfiltered value to said detection threshold to produce an unfiltered alarm signal; and an alarm comparator for comparing said unfiltered alarm signal to said filtered alarm signal to produce a censored false alarm signal.
- 8. The apparatus of the previous claim wherein:
said censored false alarm signal comprises a binary signal having a true value when said unfiltered alarm signal differs from said filtered alarm signal and a false value otherwise; and said apparatus further comprises a counter for counting said false values to produce a censored false alarm count.
- 9. The apparatus of the previous claim further comprising a failure isolator for diagnosing a failure mode from said censored false alarm count.
- 10. A method for detecting hot rail car surfaces, the method comprising:
acquiring an infrared signal from a rail car surface of a rail car; transducing said infrared signal into an electrical signal; filtering said electrical signal using a rank filter to produce a filtered array; detecting a maximum filtered value of said filtered array; and comparing said maximum filtered value to a detection threshold to produce a filtered alarm signal.
- 11. The method of claim 10 wherein said rank filter has a rank of about one-half.
- 12. The method of claim 10 further comprising:
acquiring rail car surface characteristics from a wireless tag mounted on said rail car; and calculating a filter length and rank of said rank filter as a function of said rail car surface characteristics.
- 13. The method of claim 10 further comprising:
buffering said electrical signal to produce an unfiltered array; detecting a maximum unfiltered value of said unfiltered array; comparing said maximum unfiltered value to said detection threshold to produce an unfiltered alarm signal; and comparing said unfiltered alarm signal to said filtered alarm signal to produce a censored false alarm signal.
- 14. The method of the previous claim wherein:
said censored false alarm signal comprises a binary signal having a true value when said unfiltered alarm signal differs from said filtered alarm signal and a false value otherwise; and said method further comprises counting said false values to produce a censored false alarm count.
- 15. The method of the previous claim further comprising diagnosing a failure mode from said censored false alarm count.
- 16. A method for detecting hot rail car surfaces, the method comprising:
acquiring an infrared signal from a rail car surface of a rail car; transducing said infrared signal into an electrical signal; filtering said electrical signal using a rank filter to produce a filtered array; detecting a maximum filtered value of said filtered array; comparing said maximum filtered value to a detection threshold to produce a filtered alarm signal; acquiring rail car surface characteristics from a wireless tag mounted on said rail car; calculating a filter length and rank of said rank filter as a function of said rail car surface characteristics; buffering said electrical signal to produce an unfiltered array; detecting a maximum unfiltered value of said unfiltered array; comparing said maximum unfiltered value to said detection threshold to produce an unfiltered alarm signal; and comparing said unfiltered alarm signal to said filtered alarm signal to produce a censored false alarm signal.
- 17. The method of the previous claim wherein:
said censored false alarm signal comprises a binary signal having a true value when said unfiltered alarm signal differs from said filtered alarm signal and a false value otherwise; and said method further comprises counting said false values to produce a censored false alarm count.
- 18. The method of the previous claim further comprising diagnosing a failure mode from said censored false alarm count.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This Application is a continuation-in-part of U.S. application Ser. No. 10/063,218, filed Mar. 29, 2002, which application is herein incorporated by reference.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
10063218 |
Mar 2002 |
US |
Child |
10063950 |
May 2002 |
US |