Methods for infrared inspection using programmed logic

• US 7,902,507 B1
• Filed: 03/26/2009
• Issued: 03/08/2011
• Est. Priority Date: 10/19/2005
• Status: Active Grant

• Current Assignee: Computational Systems Incorporated (Emerson Electric Company)
• Original Assignee: CSI Technology Incorporated (Emerson Electric Company)
• Inventors: Garvey, Raymond E. III, Sheirik, Robert Darrell
• Primary Examiner(s): Porta; David P
• Assistant Examiner(s): Kim; Kiho
• Application Number:
  US12/411,530
• Time in Patent Office: 712 Days
• Field of Search: 250/330
• US Class Current: 250/330
• CPC Class Codes: G01J 5/00 Radiation pyrometry, e.g. infrared or optical thermometry
• CPC Class Codes: G01J 5/025 Interfacing a pyrometer to an external device or network; User interface
• CPC Class Codes: G01J 5/0265 Handheld, portable ear thermometers G01J5/049
• CPC Class Codes: G01J 5/07 Arrangements for adjusting the solid angle of collected radiation, e.g. adjusting or orienting field of view, tracking position or encoding angular position optical collimating elements G01J5/0806
• CPC Class Codes: G01J 5/0859 Sighting arrangements, e.g. cameras

Abstract

A system and method for enhancing inspections using infrared cameras through in-field displays and operator-assisted performance calculations. A handheld infrared imaging system typically includes an infrared camera having a programmed computer and an interactive user interface suitable for displaying images and prompting response and accepting input from the infrared camera operator in the field during an inspection. An operator may designate at least one thing of interest on a displayed infrared image; and the programmed computer may uses a performance algorithm to estimate performance associated with the thing of interest. The programmed computer may extract information or parameters from previously measured data—. The programmed computer may vary the way in which it displays new measurements based on the information extracted from the stored data. One or more of the parameters extracted from the IR image may be adapted to provide an automated alert to the user.

Claims

1. A method for analyzing a building using a computerized thermal imaging tool having programmed logic and a visual display comprising:

(a) acquiring a thermal image of at least a portion of the building;

(b) producing on the visual display a thermal image of the at least a portion of the building;

(c) using the programmed logic to calculate an area value representing a geometric area of the thermal image;

(d) providing information regarding a building material selected from the group consisting of

(i) an insulation R-value characteristic of the building material,

(ii) a wet-material R-value characteristic of the building material,

(iii) a missing material R-value characteristic of the building material, and,

(iv) combinations of two or more thereof;

(e) using the programmed logic to operate on the area value and the R-value characteristic of the building material to calculate a parameter value selected from the group consisting of

(i) an insulation value,

(ii) an energy value,

(iii) a monetary expense value, and

(iv) combinations of two or more thereof; and

(f) outputting the parameter value.

2. The method of claim 1 wherein providing information in step (d) comprises prompting the operator to provide the information as user input.

3. The method of claim 1 wherein using the programmed logic to calculate an area value comprises at least one step using a reference dimension that is estimated from a known dimension of at least a portion of an object.

4. A method for generating a fire characteristic alert to warn of possible danger using a computerized thermal imaging tool having programmed logic and comprising:

(a) acquiring thermal image information for an area of fire danger;

(b) using the programmed logic to analyze the thermal image information and identify evidence of a possible danger selected from the group consisting of

(i) rollover,

(ii) incomplete overhaul, and

(iii) combinations of two or more thereof; and

(c) generating the fire characteristic alert.

5. The method of claim 4 wherein the computerized thermal imaging tool further comprises a visual display and the step of generating the fire characteristic alert comprises generating the fire characteristic alert on the visual display.

6. The method of claim 4 wherein the computerized thermal imaging tool further comprises an audio speaker and the step of generating the fire characteristic alert comprises generating the fire characteristic alert using the audio speaker.

7. The method of claim 4 wherein the programmed logic evaluates a danger of rollover using a step comprising identifying high temperature and transient temperature conditions that are specified in the programmed logic as being characteristic of rollover.

8. The method of claim 4 wherein the programmed logic evaluates a danger of incomplete overhaul using a step comprising identifying relative hot spots in the thermal image that are characteristic of incomplete overhaul.

9. A method for inspecting electrical equipment for an electrical fault using a computerized thermal imaging tool having programmed logic and a visual display comprising

(a) acquiring at least one thermal image depicting a first electrical component and a second electrical component presumed to be operating under similar conditions, wherein the first electrical component is apparently anomalous and the second electrical component is apparently normal;

(b) identifying from the at least one thermal image a first approximately highest temperature corresponding to the first electrical component and a second approximately highest temperature corresponding to the second electrical component;

(c) identifying an ambient temperature for the environment around the first electrical component and the second electrical component;

(d) using the programmed logic to operate on at least the approximately highest temperature for the first component and the approximately highest temperature for

the second component and the ambient temperature to compute an electrical fault parameter selected from the group consisting of

(i) time-to-failure, wherein the programmed logic further utilizes a value representing limit life,

(ii) safe distance, wherein the programmed logic further utilizes a value for fault capacity,

(iii) electrical contact resistance, wherein the programmed logic further utilizes a value for specified contact resistance, and

(iv) combinations of two or more thereof; and

(e) outputting the electrical fault parameter.

10. A method for evaluating an operational status of an inspected valve using a computerized thermal imaging tool having programmed logic and having a database of valve operating characteristic data for a plurality of reference valves each associated with a valve identifier and having a user interface for user input and having a visual display comprising:

(a) acquiring a thermal image of the inspected valve;

(b) using the programmed logic to prompt the user to input an inspected valve identifier for the inspected valve, using the user interface;

(c) using the programmed logic to search the database of valve operating characteristic data to find valve operating characteristic data for the inspected valve identifier; and

(d) acquiring at least one additional thermal image of the inspected valve and using the programmed logic and the valve operating characteristic data for the inspected valve to output an estimated operational status of the inspected valve selected from the group consisting of

(i) valve is normal,

(ii) valve is failed open,

(iii) valve is failed closed,

(iv) valve is intermittent,

(v) valve is not operating, and

(vi) combinations of two or more thereof.

11. The method of claim 10 further comprising using the programmed logic to output an estimated monetary expense based upon at least the estimated operational status.

12. A method for calculating a geometric characteristic of an object in an image produced by a portable infrared imaging apparatus generating a plurality of pixels and having programmed logic comprising:

(a) defining a field-of-view comprising at least one pixel;

(b) using the programmed logic to determine a known reference distance between a first point and a second point equal to a first image expanse represented by the field-of-view;

(c) using the programmed logic to determine a second image expanse between a third point and fourth point spaced apart a first unknown distance in the image; and

(d) using the programmed logic to calculate an estimated distance between the third point and the fourth point in the image using the known reference distance and a ratio between the first image expanse and the second image expanse, wherein the estimated distance is a proximity to possible danger to an operator of the portable infrared imaging apparatus.

13. A method for generating a fire characteristic alert to warn of possible danger using a computerized thermal imaging tool having programmed logic and comprising:

(a) acquiring thermal image information for an area of fire danger;

(b) using the programmed logic to analyze the thermal image information and identify evidence of a possible danger of flashover using a step comprising calculating a vertical temperature gradient and estimating an elevation above which temperature is above a threshold value specified in the program programmed logic as being sufficient to ignite flammable materials in the presence of oxygen; and

(c) generating the fire characteristic alert.

14. A method for generating a fire characteristic alert to warn of possible danger using a computerized thermal imaging tool having programmed logic and comprising:

(a) acquiring thermal image information for an area of fire danger;

(b) using the programmed logic to evaluate a danger of rollover using a step comprising identifying high temperature and transient temperature conditions that are specified in the programmed logic as being characteristic of rollover; and

(c) generating the fire characteristic alert.

15. A method for generating a fire characteristic alert to warn of possible danger using a computerized thermal imaging tool having programmed logic and comprising:

(a) acquiring thermal image information for an area of fire danger;

(b) using the programmed logic to evaluate a danger of incomplete overhaul using a step comprising identifying relative hot spots in the thermal image that are characteristic of incomplete overhaul; and

(c) generating the fire characteristic alert.

16. A method for calculating a geometric characteristic of an object in an image produced by a portable infrared imaging apparatus generating a plurality of pixels and having programmed logic comprising:

(a) defining a field-of-view comprising at least one pixel;

(b) using the programmed logic to determine a known reference distance between a first point and a second point equal to a first image expanse represented by the field-of-view;

(c) using the programmed logic to determine a second image expanse between a third point and fourth point spaced apart a first unknown distance in the image;

(d) using the programmed logic to calculate an estimated distance between the third point and the fourth point in the image using the known reference distance and a ratio between the first image expanse and the second image expanse, wherein the estimated distance between the third point and the fourth point is a programmed-logic-calculated safe distance boundary derived using a safe distance formula; and

(e) displaying at least a portion of the safe distance boundary in the image.

17. A method for calculating a geometric characteristic of an object in an image produced by a portable infrared imaging apparatus generating a plurality of pixels and having programmed logic comprising:

(a) defining a field-of-view comprising at least one pixel;

(b) using the programmed logic to determine a known reference distance between a first point and a second point equal to a first image expanse represented by the field-of-view;

(c) using the programmed logic to determine a second image expanse between a third point and fourth point spaced apart a first unknown distance in the image; and

(d) using the programmed logic to calculate an estimated distance between the third point and the fourth point in the image using the known reference distance and a ratio between the first image expanse and the second image expanse; and

(e) using the estimated distance between the third point and the fourth point to determine a valve operating characteristic.

18. A method for generating a fire characteristic alert to warn of possible danger using a computerized thermal imaging tool having programmed logic and comprising:

(a) acquiring thermal image information for an area of fire danger;

(b) using the programmed logic to analyze the thermal image information and identify evidence of a possible danger from flashover if oxygen is introduced; and

(c) generating the fire characteristic alert.