Method for generating a signal vibration alert

• US 6,720,885 B1
• Filed: 11/13/2001
• Issued: 04/13/2004
• Est. Priority Date: 11/01/2001
• Status: Active Grant

• Current Assignee: ProMOS Technologies, Inc.
• Original Assignee: ProMOS Technologies, Inc.
• Inventors: Lee, Chin-Wen, Chiou, Hung-Wen
• Primary Examiner(s): Wu, Daniel J.
• Application Number:
  US09/993,436
• Time in Patent Office: 882 Days
• Field of Search: 340/679, 340/683, 340/690, 340/680, 736/60, 735/93, 736/59, 700/175, 702/56
• US Class Current: 340/683
• CPC Class Codes: G05B 23/0235 based on a comparison with predetermined threshold or range, e.g. "classical methods", carried out during normal operation; threshold adaptation or choice; when or how to compare with the threshold

Abstract

The present invention provides a method for signal vibration alert. The method of the present invention recognizes significant substantial swerves and corresponding substantial edge-to-edge differences by eliminating the adverse effect of noise among signals generated by an apparatus. When the frequency of the substantial edge-to-edge differences that exceed an acceptable range of the frequency limit is too large, the method of the present invention automatically generates an alert to indicate aberration in the apparatus such that the monitoring staff is informed and allowed to take necessary measures responding to the aberration.

Claims

1. A method for signal vibration alert, comprising:

collecting a plurality of signals generated by an apparatus within a time interval;

recognizing a plurality of substantial swerves and a plurality of corresponding substantial edge-to-edge differences based on the plurality of signals, wherein every three consecutive substantial swerves constitute a peak or a valley, each substantial edge-to-edge difference is the edge-to-edge difference between every two consecutive swerves, and each substantial edge-to-edge difference exceeds a predetermined noise range;

calculating a frequency of the substantial edge-to-edge differences exceeding an acceptable range; and

automatically indicating an aberration in the apparatus when the frequency exceeds a predetermined frequency limit.

2. The method of claim 1, wherein the step of recognizing the substantial swerves further comprises:

ignoring a noise signal having a corresponding difference between a local minimum (LocalMin) or a local maximum (LocalMax) within the predetermined noise range;

setting one of the substantial swerves as the LocalMin and setting the LocalMax as an instant signal when a trend changes to ascending;

concluding the LocalMax as the maximum between the LocalMax and the instant signal when the trend remains ascending;

setting one of the substantial swerves as the LocalMax and setting the LocalMin as the instant signal when the trend of the noise turns to be descending; and

concluding the LocalMin as a minimun between the LocalMin and the instant signal when the trend of the noise remains descending.

3. The method of claim 1, wherein the step of recognizing the substantial swerves further comprises:

a. sequentially recognizing a plurality of swerves based on the signals;

b. recognizing two consecutive swerves among the swerves wherein two consecutive swerves are a first swerve S₁ and a second swerve S₂;

c. repeating step (b) and substituting four consecutive swerves S₀, S₁, S₂ and S₃ with a S_M1 and a S_M2 when the edge-to-edge difference between S₁ and S₂ falls within a predetermined noise range, wherein S_M1 is the first extreme value between S₁, S₃, and S_M2 is the second extreme value between S₂, S₄; and

setting the swerves as the substantial swerves when the edge-to-edge difference of two adjacent swerves among the swerves exceeds the predetermined noise range.

4. The method of claim 1, wherein the substantial edge-to-edge differences comprises a plurality of ascending edge-to-edge differences and a plurality of descending edge-to-edge differences.

5. The method of claim 4, wherein the acceptable range comprises an acceptable ascending range and a acceptable descending range.

6. The method of claim 5, wherein the predetermined frequency limit comprises an ascending frequency limit and a descending frequency limit, if an ascending frequent for the ascending edge-to-edge differences exceeding the acceptable ascending range is higher than the ascending frequency limit, an alert is generated automatically to indicate aberration in the apparatus, if the descending frequency for the descending edge-to-edge differences exceeding the acceptable descending range is higher than the descending frequency limit, an alert is generated automatically to indicate aberration in the apparatus.