System for monitoring an industrial or biological process

• US 5,774,379 A
• Filed: 07/21/1995
• Issued: 06/30/1998
• Est. Priority Date: 07/21/1995
• Status: Expired due to Term

• Current Assignee: Energizer Brands, LLC (Energizer Holdings, Inc.)
• Original Assignee: University of Chicago
• Inventors: Wegerich, Stephan W., Gross, Kenneth C., White, Andrew M., Vilim, Rick B.
• Primary Examiner(s): Voeltz, Emanuel T.
• Assistant Examiner(s): KEMPER, MELANIE A
• Application Number:
  US08/505,453
• Time in Patent Office: 1,075 Days
• Field of Search: 364/576, 364/551.01, 364/554, 364/480, 364/413.01, 364/413.03, 364/413.05, 364/413.06, 364/485, 364/486, 364/487, 364/569, 364/421, 128/633, 607/115
• US Class Current: 702/72
• CPC Class Codes: G06Q 99/00 Subject matter not provided for in other groups of this subclass

Abstract

A method and apparatus for monitoring and responding to conditions of an industrial process. Industrial process signals, such as repetitive manufacturing, testing and operational machine signals, are generated by a system. Sensor signals characteristic of the process are generated over a time length and compared to reference signals over the time length. The industrial signals are adjusted over the time length relative to the reference signals, the phase shift of the industrial signals is optimized to the reference signals and the resulting signals output for analysis by systems such as SPRT.

Claims

1. A method for monitoring an industrial testing process, comprising the steps of:

(a) providing to a data acquisition system a set of industrial testing signals over a time length and a reference signal over another time length, said industrial testing signals and said reference signal being aperiodic within said time lengths;

(b) adjusting the time length of the industrial signals to the time length of the reference signal, forming a difference between the time length adjusted industrial signals and the reference signal; and

(c) outputting the difference between the time length adjusted testing signals and the reference signal for variance minimization and repeating steps (b) and (c) until achieving a minimum variance.

2. The method as defined in claim 1 wherein said set of industrial signals comprises signals from a biological process.

3. The method as defined in claim 1 wherein said set of industrial signals comprises signals from a battery functionality test.

4. The method as defined in claim 1 wherein said set of industrial signals comprises repetitive industrial operational signals.

5. The method as defined in claim 4 wherein said set of industrial signals comprises repeated sensor signals from an avionics system.

6. The method as defined in claim 4 wherein said set of industrial signals comprises repeated electronic sensor signals from testing of a manufactured solid-state device.

7. The method as defined in claim 1 further including the step of performing a SPRT analysis.

8. The method as defined in claim 7 further including the step of responding to the SPRT analysis to modify the industrial process.

9. A method for monitoring an industrial process, comprising the steps of:

(a) providing to a data acquisition system a set of industrial signals over a time length and a reference signal over another time length, said industrial signals and said reference signal being aperiodic within said time lengths;

(b) adjusting the time length of the industrial signals to the time length of the reference signal;

(c) performing a phase shift optimization of the industrial signals relative to the reference signal; and

(d) outputting for analysis the difference between the time adjusted and phase shift optimized industrial signals and determining a minimum variance for the difference.

10. The method as defined in claim 9 wherein the time length adjustment is performed on at least a portion of the industrial signal.

11. The method as defined in claim 9 wherein the phase shift optimization step comprises determining a vector cross correlation function, performing a low-pass filtration of the cross correlation function, and calculating a phase shift between the industrial signals and the reference signal.

12. The method as defined in claim 11 wherein said step of calculating a phase shift comprises differentiating the vector cross correlation function with respect to a lag time for each of the industrial signals and the reference signal pairwise performing an inverse Lagrangian interpolation technique by determining the value of the lag time at which the derivative vanishes to define a phase shift correction.

13. The method as defined in claim 11 wherein said step of calculating a phase shift comprises finding a maximum among elements of the vector cross correlation function.

14. An apparatus for monitoring an industrial process, comprising:

(a) means for providing to a data acquisition system a set of aperiodic industrial signals within a time length and an aperiodic reference signal over another time length;

(b) means for adjusting the time length of the industrial signals to the another time length of the reference signal; and

(c) means for outputting the time length adjusted industrial signals for achieving a minimum variance of the difference between the industrial signal and the reference signal.

15. The apparatus as defined in claim 14 further including means for performing phase shift optimization of the industrial signals relative to the reference signal and said step of outputting comprising outputting the phase shift optimized and the time length adjusted industrial signals.

16. The apparatus as defined in claim 15 further including means for performing SPRT analysis on the output time length adjusted and phase shift optimized industrial signals.