IP Library › Granted Patent US 11,494,888
Granted Patent B2
US 11,494,888 · App. 16/771,103 · Granted Nov 8, 2022

Work terminal, oil leakage detection apparatus, and oil leakage detection method

Inventors: Li Lu (Tokyo, JP); Akira Nishimizu (Tokyo, JP); Toshiaki Rokunohe (Tokyo, JP); Akira Yamagishi (Tokyo, JP)
Assignee: Hitachi, Ltd.
G06T7/0004G01C3/02G01M3/38G01S19/01G06T2207/10024G06T2207/10152
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 11,494,888
App. No.
16/771,103
Granted
Nov 8, 2022
Kind
B2
Abstract

Provided is an oil leakage detection apparatus by which oil leakage detection is performed even for colorless oil with high detection accuracy and without complicating the apparatus. The oil leakage detection apparatus of the invention includes a distance measurement unit configured to measure a distance to the oil-input machine, an ultraviolet light source configured to irradiate the oil-input machine with ultraviolet light, a color imaging unit configured to capture an image of the oil-input machine irradiated with ultraviolet light, an image processing unit configured to diagnose oil leakage of the oil-input machine based on the distance measured by the distance measurement unit and the captured image of the color imaging unit, and a display unit configured to display a processed image processed by the image processing unit. Further, an oil leakage detection method of the invention includes measuring a distance from an oil-input machine, irradiating the oil-input device with ultraviolet light, capturing an image of the oil-input machine irradiated with ultraviolet light, diagnosing oil leakage of the oil-input machine based on the measured distance and the captured image, and displaying a processed image after the diagnosis processing.

Claims (63)

1. A work terminal used in an oil leakage detection apparatus that detects oil leakage in an oil-input machine, the work terminal comprising:

a distance measurement unit configured to measure a distance to the oil-input machine;

an ultraviolet light source configured to irradiate the oil-input machine with ultraviolet light;

a color imaging unit configured to capture an image of the oil-input machine;

a communication unit configured to transmit distance data acquired by the distance measurement unit and image data acquired by the color imaging unit;

an image processing unit is configured to: i) calculate a lightness value and a saturation value of each pixel from a Red value, a Green value, and a Blue value of each pixel of the captured image, ii) plot lightness values and saturation values on a lightness-saturation graph in which a horizontal axis represents saturation and a vertical axis represents lightness, iii) create a lightness-saturation characteristic straight line of the oil-input machine from the lightness-saturation graph, iv) diagnose a part corresponding to a pixel group higher than an upper threshold straight line parallel to the lightness-saturation characteristic straight line or a part corresponding to a pixel group lower than a lower threshold straight line parallel to the lightness-saturation characteristic straight line as oil leakage, and v) sets an interval between the lightness-saturation characteristic straight line and the upper threshold straight line, and an interval between the lightness-saturation characteristic straight line and the lower threshold straight line to be inversely proportional to the distance measured by the distance measurement unit.

2. An oil leakage detection apparatus comprising:

a distance measurement unit configured to measure a distance to an oil-input machine;

an ultraviolet light source configured to irradiate the oil-input machine with ultraviolet light;

a color imaging unit configured to capture an image of the oil-input machine irradiated with ultraviolet light;

an image processing unit configured to diagnose oil leakage of the oil-input machine based on the distance measured by the distance measurement unit and the captured image of the color imaging unit; and

a display unit configured to display a processed image processed by the image processing unit, wherein

the image processing unit is configured to

calculate an irradiation intensity of ultraviolet light emitted from the ultraviolet light source to a surface of the oil-input machine by using the distance measured by the distance measurement unit,

calculate a variation width of lightness or saturation of a pixel group corresponding to a leaked oil non-adhesion portion by using the irradiation intensity,

create a lightness-saturation characteristic straight line of the leaked oil non-adhesion portion by using the variation width, and

determine an upper threshold straight line and a lower threshold straight line parallel to the lightness-saturation characteristic straight line by using the variation width.

3. The oil leakage detection apparatus according to claim 2 , wherein

the oil leakage detection apparatus includes a wearable device configured to be worn by a field worker, and a computer separated from the wearable device,

the wearable device is provided with the distance measurement unit, the ultraviolet light source, the color imaging unit, the display unit, and a first communication unit, and

the computer is provided with a second communication unit configured to communicate with the first communication unit, and the image processing unit.

4. The oil leakage detection apparatus according to claim 3 , wherein

the wearable device includes a head unit configured to be worn on a head of the field worker, and a body unit configured to be worn on a body of the field worker,

the color imaging unit and the display unit are disposed on the head unit, and

the ultraviolet light source and the distance measurement unit are disposed on the body unit.

5. The oil leakage detection apparatus according to claim 2 , wherein

the processed image displayed on the display unit is an image in which a leaked oil adhesion portion of the captured image is emphasized.

6. The oil leakage detection apparatus according to claim 2 , wherein

the distance measurement unit is a laser displacement meter, and

an irradiation position of a laser beam of the laser displacement meter is within an irradiation range of the ultraviolet light source.

7. The oil leakage detection apparatus according to claim 2 , wherein

the image processing unit is configured to

calculate a lightness value and a saturation value of each pixel from a Red value, a Green value, and a Blue value of each pixel of the captured image,

plot lightness values and saturation values on a lightness-saturation graph in which a horizontal axis represents saturation and a vertical axis represents lightness,

create a lightness-saturation characteristic straight line of the oil-input machine from the lightness-saturation graph, and

diagnose a part corresponding to a pixel group higher than an upper threshold straight line parallel to the lightness-saturation characteristic straight line or a part corresponding to a pixel group lower than a lower threshold straight line parallel to the lightness-saturation characteristic straight line as oil leakage.

8. The oil leakage detection apparatus according to claim 7 , wherein

the image processing unit sets an interval between the lightness-saturation characteristic straight line and the upper threshold straight line, and an interval between the lightness-saturation characteristic straight line and the lower threshold straight line to be inversely proportional to the distance measured by the distance measurement unit.

9. The oil leakage detection apparatus according to claim 2 , wherein

the color imaging unit captures images of the same part of the oil-input machine from different directions, and

the image processing unit extracts an oil leakage part of the oil-input machine based on a plurality of captured images, and diagnoses an overlapping part of a plurality of extracted oil leakage parts as a final oil leakage part.

10. The oil leakage detection apparatus according to claim 2 , wherein

the distance measurement unit is a global positioning system receiver, and the color imaging unit is an angle measurement camera.

11. The oil leakage detection apparatus according to claim 2 , wherein

the image processing unit marks a diagnosis result of oil leakage on the displayed oil-input machine.

12. The oil leakage detection apparatus according to claim 2 , wherein

the color imaging unit captures an image of a temporal change of the oil-input machine,

the image processing unit machine-learns an oil leakage diagnosis result by a captured image at each time point, and

any one of a prediction of a next oil leakage part, a prediction of an oil leakage amount, and a prediction of a maintenance period of the oil-input machine is performed.

13. The oil leakage detection apparatus according to claim 2 , wherein

the oil leakage detection apparatus includes a wearable device configured to be worn by a field worker, and a flexible, elongated moving device separated from the wearable device,

the display unit is disposed on the wearable device, and

the distance measurement unit, the ultraviolet light source, and the color imaging unit are disposed on a distal end side of the moving device.

14. An oil leakage detection method comprising:

measuring a distance from an oil-input machine;

irradiating the oil-input device with ultraviolet light;

capturing an image of the oil-input machine irradiated with ultraviolet light; diagnosing oil leakage of the oil-input machine based on the measured distance and the captured image;

displaying a processed image after the diagnosis processing, wherein the diagnosis of oil leakage includes:

calculating a lightness value and a saturation value of each pixel from a Red value, a Green value, and a Blue value of each pixel of the captured image,

plotting lightness values and saturation values on a lightness-saturation graph in which a horizontal axis represents saturation and a vertical axis represents lightness,

creating a lightness-saturation characteristic straight line of the oil-input machine from the lightness-saturation graph, and

diagnosing a part corresponding to a pixel group higher than an upper threshold straight line parallel to the lightness-saturation characteristic straight line or a part corresponding to a pixel group lower than a lower threshold straight line parallel to the lightness-saturation characteristic straight line as oil leakage, wherein

an interval between the lightness-saturation characteristic straight line and the upper threshold straight line and an interval between the lightness-saturation characteristic straight line and the lower threshold straight line are set to be inversely proportional to the measured distance.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 8, 2024
From: HITACHI, LTD.
To: HITACHI ENERGY LTD
Reel/Frame 069534/0519 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 10, 2020
From: LU, LI; NISHIMIZU, AKIRA; ROKUNOHE, TOSHIAKI; YAMAGISHI, AKIRA
To: HITACHI, LTD.
Reel/Frame 052897/0644 →
Priority Claims (2)
JP JP2018-006383 · Jan 18, 2018 · national
JP JP2018-104424 · May 31, 2018 · national
Continuity (1)
Related Publication 20210192710A1 · Jun 24, 2021