Leak detection systems and methods

Abstract

Methods and systems for detecting a leak within a hydraulic valve are disclosed. The methods include activating, via a controller, a camera and a light source, taking, via the camera, a first image of a valve, pressurizing the valve with a dyed fluid to a predetermined pressure value, the dyed fluid to emit a fluorescent glow in response to illumination via the light source, taking, via the camera, a second image of the valve after pressurization of the valve, comparing, via a processor, the first image of the valve to the second image of the valve, and detecting, via the processor, a leak when fluorescent glow is detected in the second image.

Description

LEAK DETECTION SYSTEMS AND METHODSCROSS-REFERENCES TO RELATED APPLICATIONS

[0001] The present application is based on and claims the benefit of U.S. Provisional Patent Application No. 63 / 519,472, filed on August 14, 2023, which is incorporated herein by reference in its entirety .BACKGROUND

[0002] Valves, such as hydraulic valves, are ty pically designed to mitigate the loss of fluid (e.g., hydraulic fluid) via external leakage. In some examples, the valves may be leak tested during manufacture in a variety of ways, such as bubble testing, gas sniffing, and / or visual inspection by an operator. However, these methods of leak testing can be inaccurate and / or inconsistent. For example, leak testing via the use of gas pressurization may not adequately mirror the intended use of the valves, which can lead to inconsistencies in testing versus real- world performance.SUMMARY

[0003] According to one aspect of present disclosure a method of leak testing a valve can be provided, in which a controller can activate a camera and a light source. A first image of the valve can be taken with the camera. The valve can be pressurized with a died fluid to a predetermined pressure value. The dyed fluid can emit a fluorescent glow in response to illumination via the light source. A second image of the valve can be taken with the valve in a pressurized state. A processor can compare first image of the valve with the second image of the valve. The processor can detect a leak when a fluorescent glow can be detected in the second image.

[0004] In some examples, the light source can emit light at a first wavelength. The dyed fluid can emit the florescent glow at a second wavelength in response to the illumination via the light source. In some cases, the camera can be moved with robotic arm that can be controlled by the processor.

[0005] In some examples, detecting the leak can include reviewing each pixel in the first image and the second image, and changing a color of one or more of the pixels to a first color based on the presence of fluorescent glow from the dyed fluid. In some cases, the processor can group a number of pixels in both the first image and the second image into a first group and second group, respectively, based on the color of the pixels. The processor can map thesecond image of the valve onto the first image of the valve. In some cases, the processor can calculate the number of pixels in the first group and the number of pixels in the second group and can compare the number of pixels in the first group to the number of pixels in the second group. A leak can be indicated as being present when the number of pixels in the second group is larger than a number of pixels in the first group by a predetermined factor. No leak can be indicated when the number of pixels in the second group is smaller than a number of pixels in the first group multiplied by a predetermined factor.

[0006] According to another aspect of the present disclosure, a non-transitory machine- readable storage medium encoded with instructions executable by a processor is provided. The machine-readable storage medium can include instructions to, when executed by the processor, cause the processor to activate a camera and a light source, take a first image of a valve via the camera, pressurize the valve with a dyed fluid to a predetermined pressure value, the dyed fluid to give off a fluorescent glow in response to illumination via the light source, take a second image of the valve after pressurization of the valve, compare the first image of the valve to the second image of the valve, and detect a leak when fluorescent glow can be detected in the second image.

[0007] In some examples, the processor groups a number of pixels in both the first image and the second image of the valve into a first image group and a second image group, respectively, based on the presence of fluorescent glow from the dyed fluid, and maps the second image of the valve onto the first image of the valve. In some cases, the processor counts the number of pixels in the first image group, counts the number of pixels in the second image group, and compares the number of pixels in the first image group to the number of pixels in the second image group. In some cases, the processor compares a location of the first image group to a location of the second image group and determines the location of the first image group can be similar to the location of the second image group. The processor can indicate a leak is present when the number of pixels in the second image group can be larger than a number of pixels in the first image group. The processor can indicate no leak is present when the number of pixels in the second image group can be smaller than a number of pixels in the first image group. In some cases, the processor changes a color of one or more of the pixels to a first color based on the presence of fluorescent glow from the dyed fluid and groups the one or more pixels based on color and proximity' relative to one another.

[0008] According to another aspect of the present disclosure a system fo detecting a leak in a valve is provided. The system can include a stand configured to hold the valve and a light source configured to emit a light onto the valve. A pump can be configured to supply a fluid tothe valve to pressurize the valve. The fluid can include a dye that fluoresces in response to the light emitting by the light source. A camera can be configured to take images of the valve. A processor can be configured to activate the light source to emit the light on the valve, control the camera to take a first image of the valve in an unpressurized state, control the cameral to take a second image of the valve in a pressurized state, and compare the first image with the second image and determine a presence of a leak based on whether a fluorescent glow of the fluid can be detected in the second image.

[0009] In some examples, the light source and the camera are coupled to a robotic arm and the processor can be configured to control operation of the robotic arm. The first image and the second image can be taken at a first position of the robotic arm and the processor can be further configured to take a third image of a third image of the valve in an unpressurized state and a fourth image of the valve in a pressurized state. Thee third image and the fourth image can be taken at a second position of the robotic arm that is different from the first position. In some cases, the processor can be further configured to operate the pump to supply the fluid to the valve.

[0010] The foregoing and other aspects and advantages of the disclosure will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by w ay of illustration a preferred configuration of the disclosure. Such configuration does not necessarily represent the full scope of the disclosure, however, and reference is made therefore to the claims and herein for interpreting the scope of the disclosure.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The invention will be better understood and features, aspects and advantages other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such detailed description makes reference to the following drawings.

[0012] FIG. 1 is a schematic view of a leak detection system according to one aspect of the present disclosure.

[0013] FIG. 2 is a perspective view of one example of the leak detection system of FIG. 1.

[0014] FIG. 3 is a schematic view of a robotic arm of the leak detection system of FIG. 1.

[0015] FIG. 4 is a flowchart of a leak detection process for use with the leak detection system of FIG. 1 .

[0016] FIG. 5 is a flowchart of another leak detection process for use with the leak detection system of FIG. 1.

[0017] FIG. 6 is a flowchart of yet another a leak detection process for use with the leak detection system of FIG. 1.

[0018] FIG. 7A is a flowchart of still another leak detection process for use with the leak detection system of FIG. 1.

[0019] FIG. 7B is a continuation of the flowchart of FIG. 7A.

[0020] FIG. 7C is a continuation of the flowchart of FIGS. 7A and 7B.

[0021] FIG. 7D is a continuation of the flowchart of FIGS. 7A, 7B, and 7C.

[0022] FIG. 8 is an example image according to one aspect of the present disclosure.

[0023] FIG. 9 is an example image according to one aspect of the present disclosure.

[0024] FIG. 10 is an example first image and second image according to one aspect of the present disclosure.

[0025] FIG. 11 is an example conversion of images to data arrays according to one aspect of the present disclosure.

[0026] FIG. 12 is an example computational technique applied to the data arrays of FIG. 11.DETAILED DESCRIPTION

[0027] Disclosed embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all of the disclosed embodiments are shown. Indeed, several different embodiments may be provided and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the disclosure to those skilled in the art.

[0028] The following detailed description is to be read with reference to the figures, in which like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected examples and are not intended to limit the scope of examples of the invention. Skilled artisans will recognize the examples provided herein have many useful alternatives and fall within the scope of examples of the invention.

[0029] The reference numerals in the following description have been organized to aid the reader in quickly identifying the drawings where various components are first shown. In particular, the drawing in which an element first appears is typically indicated by the left-most digit(s) in the corresponding reference number. For example, an element identified by a “100”series reference numeral will likely first appear in FIG. 1, an element identified by a “200” series reference numeral will likely first appear in FIG. 2. and so on.

[0030] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being earned out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings.

[0031] The use of the terms “downstream” and “upstream” herein are terms that indicate direction relative to the flow of a fluid. The term “downstream” corresponds to the direction of fluid flow, while the term “upstream” refers to the direction opposite or against the direction of fluid flow.

[0032] As generally mentioned above, valves (e.g., hydraulic valves) can be leak tested during manufacturing so that leaks can be fixed prior to installation of the valve on a machine, or other use of the valve. Conventional leak testing methods can include, for example, bubble testing, gas sniffing, and / or visual inspection by an operator. However, such conventional methods may not always detect a leak. For example, with bubble testing, tests typically occur at pressures significantly lower than an operational pressure of the valve. Accordingly, leaks that occur upon reaching operating pressures may not be present during the test and may be missed. Moreover, leaks and their resulting bubbles can be very small, making leaks hard to identify. Similar deficiencies are present with gas sniffing tests, in which the source of a leak can be difficult to identify’, and with human visual inspection, which can be inconsistent in identifying leaks, even with proper operator training.

[0033] Aspects of the present disclosure can address some or all of the deficiencies with conventional methods for leak detection by using cameras to identify a light-reactive dyed fluid 135 leaking out of a valve. In one example, a leak detection system may include at least one camera and a stand (e.g.. a robotic arm) configured to hold the camera (e.g.. a first camera), for example, to scan one or more sides and a top and / or bottom of a valve. In some cases, multiplecameras may be used to capture different areas of the valve. For example, a second camera can be used to scan an underside of the valve. Further, one or more light sources can be mounted adjacent the camera.

[0034] In general, the light source can be configured to emit light at a particular wavelength or range of wavelengths that result in fluorescence of the dyed fluid 135, but which are primarily absorbed by the valve. In this way, dyed fluid 135 leaking from the valve can be identified by a camera system and a remote computer. In one particular example, the light source can be configured to emit ultraviolet light, for example, light with a wavelength of about 365 nm. In other examples, the light source can be configured to emit light with a wavelength of between about 340 nm and about 390 nm. However, it should be appreciated that the spectrum of wavelengths may change based on the fluorescent dye used. In one example, the leak detection system may be positioned inside of a fixture (e.g., an enclosure, or dark-room) configured to prevent or reduce the intrusion of ambient light into the testing area (e.g., light that is not at the desired wavelength). In one example, the camera may be in wired and / or wireless communication with a remote computer including non-transitory computer-readable medium with instructions encoded thereon for leak detection analysis.

[0035] In one example, prior to leak testing a valve, the valve may be filled with a fluidic dye (e.g., fluorescent or UV -reactive oil). The use of oil or another viscous liquid for testing not only mimics real-use conditions for the valve, but also allows leak testing to occur at or above a maximum rated operating pressure of the valve.

[0036] Following this, a camera and a light source may be activated by a remote computer. Accordingly, in one example, prior to pressurization of the valve, the camera may take one or more initial photos of the valve. Following this, the valve may be pressurized to a predetermined value (e.g., up to 250 BAR). After pressurization of the valve, the camera may take one or more additional photos of the valve, which may be sent to the remote computer.

[0037] In one example, the remote computer may include a non-transilory computer- readable medium with instructions encoded thereon, as well as one or more processors configured to execute the instructions. In one example, the remote computer may review the photos taken by the camera for a fluorescent glow (e.g., of a predetermined color) emitted by the dye when hit by the one or more light sources. The remote computer may then identify (e.g., flag, circle, or otherwise indicate) the region of the photo having predetermined color, and thus the corresponding area on the valve (i.e., a leak area), as having a potential leak. In another example, the remote computer may compare images of the valve taken before and after pressurization of the valve. In one example, if the identified leak area (e.g., indicated area) isthe same in the unpressurized photos and the pressurized photos, the remote computer may indicate to an operator that no leak is present. However, if the identified leak area (e.g., indicated area) is only present after pressurization of the valve, the remote computer may identify the indicated area as a leak.

[0038] FIG. 1 shows an example of a leak detection system 100. In one example, the leak detection system 100 may be housed (e.g., positioned) inside of a fixture 105. The fixture 105 may be in the form of a dark-room and / or other enclosed space configured to prevent the intrusion of ambient light into the leak testing area. In one example, the leak detection system 100 may include a test station 110 configured to hold and / or secure one or more valves 115 (e.g., a hydraulic control valve). It is appreciated that, while the leak detection system is described herein with reference to a hydraulic valve, application of this disclosure is not limited to this particular use. Rather, leak detection systems, as described herein, can be used to identify leaks in the manufacture of a variety of fluid handling components and systems.

[0039] The leak detection system 100 may further include a stand 120 configured to support one or more cameras 125 and / or one or more light sources 130. In the illustrated nonlimiting example, the stand 120 is a robotic arm that can move a camera, or multiple cameras, to various locations relative to the valve 115 to capture potential leaks. However, in other nonlimiting examples, a stand for a camera can be configured differently, for example, as another type of moveable or articulable stand, or as a stationary stand. Correspondingly, the camera 125 may be configured to work together with the light source 130 to identify the presence and location of leaks on the valve 115 on the test station 1 10.

[0040] For example, the valve 115 may be filled with a dyed fluid 135 (e.g., a hydraulic fluid treated with a dye, or other fluid treated with a dye), which may be pressurized via a pump 116 to a predetermined pressure value (e.g., from 0-250 BAR). In some cases, the fluid used for the dyed fluid 135 can be selected to mimic a working fluid of the valve 1 15 (e.g., water, hydraulic oil, brake fluid, etc.). During pressurization of the valve 115, the robotic arm 120 may automatically move around the valve 115 to take images and / or video of the valve 115 via the cameras 125. In one example, the dyed fluid 135 may be configured to react to the light source 130. For example, the dyed fluid 135 may fluoresce in response to the emission of light from the light source 130, such that the light source 130 emits light of a first color (i.e., wavelength), which is absorbed by the dyed fluid 135 and emitted as second color (i.e., wavelength) that is different from the first color. In one particular example, the light sources 130 may emit light corresponding with the ultraviolet region of the electromagnetic spectrum (e.g., with a wavelength between about 10 nm and about 400 nm, and more specifically, about335 nm and about 395 nm, or about 365 nm), and the dyed fluid 135 can emit or fluoresce light corresponding with the visible light region of the electromagnetic spectrum (e.g.. between about 400 nm and about 700 nm). In other non-limiting examples, other portions of the electromagnetic spectrum may be used. Accordingly, the dyed fluid 135 that leaks from the valve 115 can interact with the light from the light source 130, resulting in fluorescence of a corresponding wavelength, which can be captured and differentiated by the camera 125. As should be appreciated, the portion of the electromagnetic spectrum used may correspond to the color of dyed fluid 135 used with the valve.

[0041] In one example, the cameras 125 may be in wired and / or wireless communication with an electronic device 140 (e.g., a remote computer, remote server, local computer, etc.). The electronic device 140 may be configured to parse and / or review the images and / or video from the cameras 125 to determine whether or not the valve 1 15 has one or more leaks. In one example, the electronic device 140 may include a memory 145 and a processor 150. The memory7145 may be a non-transitory computer-readable medium with instructions encoded thereon for leak detection analysis. The processor 150 may be configured to execute the instructions to review images taken via the cameras 125 to determine whether or not a leak is present. For example, the processor 150 may recognize an illuminated (e.g., colored) area of the valve 115, which corresponds to the color emitted by dyed fluid 135 when illuminated by the light sources 130.

[0042] In one particular example, the electronic device 140 may be configured to only recognize the predetermined color emitted by the dyed fluid 135 (in response to illumination via the light source 130) and ignore other colors in the one or more images from the cameras 125. In one particular example, the dyed fluid 135 can fluoresce with a yellow color when illuminated by the light source 130. Correspondingly, the electronic device 140 can be configured to identify and differentiate the yellow color and ignore other colors in the image(s) from the camera 125. However, in other examples, the dyed fluid 135 may be configured to emit other colors when illuminated by the light source 130 (e g., green, yellow-green, etc.). Thus, the presence of the dyed fluid 135 on an exterior surface of the valve 115 can indicate to the electronic device 140 that a leak may be present on the valve 115. Accordingly, the electronic device 140 may generate an alert and / or other indication for an operator that valve 115 has failed the leak test, or that additional tests are required to confirm the presence of a leak.

[0043] FIGS. 2 and 3 show example arrangements of the leak detection sy stem 100. In one example, the robot arm 120 may be mounted to a frame 205 of the fixture 105, and morespecifically, along a ceiling of the fixture 105. In other examples, the robot arm 120 may be mounted to one or more other areas of the fixture 105. For example, the robot arm 120 may be mounted to one or more walls, floors, and / or other areas of the fixture 105. In one example, the robot arm 120 may include a head 210 located at one end of the robot arm 120. The head 210 may include a circuit board 305 (e.g., a printed circuit board) configured to electrically connect the camera 125 and the light source 130.

[0044] As mentioned previously, the leak detection system 100 may include one or more cameras 125 configured to take images of the valve 115. In one particular example, the leak detection system 100 may include a first camera 212 positioned on the robot arm 120 and configured to take photos of the top and sides of the valve 115. In another example, the leak detection system 100 may include a second camera 220. The second camera 220 may be positioned on a table 215 (e.g., a stand) of the leak detection system 100. The table 215 may additionally support the test station 110 and the valve 115 such that the second camera 220 may slide under the test station 110 via a slide 225 to take photos of the underside (e.g., bottom) of the valve 115. In other examples, the cameras 212, 220 may be mounted differently. For example, the cameras 212. 220 may both be mounted to a robot arm. or each camera mounted on a separate robot arm. In another example, the cameras 212, 220 may both be fixed (e.g., non-moving), mounted on slides (e.g., slide 225), and / or any combination thereof.

[0045] FIG. 4 shows one example of a method 400 for operating the leak detection system 100. At stage 405, the valve 115 can be secured to the test station 110. In some cases, securing the valve 1 15 to the test station 1 10 can include enclosing the valve 1 15 within the corresponding enclosure (e.g., a dark room). At stage 410, the camera 125 and the light source 130 can be activated. In some cases, stage 410 can include activating the electronic device 140, which in turn, may then activate the cameras 125 and the light source 130 (e.g., via commands from the processor 150). At stage 415, the valve 115 can be pressurized to a predetermined testing pressure. For example, the electronic device 140, via the processor 150, can cause dyed fluid 135 to be supplied into the valve 115 at the testing pressure. More specifically, the electronic device 140 can operate a pump 116 to provide dyed fluid 135 to the valve 1 15 at the desired pressure value (e.g., 250 BAR).

[0046] At stage 420, an image of the valve 1 15 can be taken using the camera 125. For example, the robot arm 120 can articulate to move the camera 125 around each of sides of the test station 110 (corresponding to sides of valve 115). While the camera 125 is moved, the electronic device 140 can command the camera 125 to take one or more photos of the valve 115, for example, to capture each side of the valve 115. In one example, the motion of the robotarm 120 may be predetermined such that one or more photos of the sides of the valve 115 may be taken in a predetermined order, and at predetermined intervals. As mentioned previously, the camera 125 may automatically send, via a wired and / or wireless connection, the photos of the valve 1 15 to the electronic device 140.

[0047] At stage 425, the electronic device 140 may evaluate each of the individual pixels in each of the images for a color value, which may correspond to the presence of the dyed fluid 135 on the exterior of the valve 115, and thus a leak in the valve 1 15. For example, referring to FIG. 8, as discussed above, the electronic device 140 may be configured to recognize a predetermined color value corresponding to a color emitted by the dyed fluid 135 when illuminated by the light sources 130. In one particular example, the color may be a yellow color. Accordingly, the electronic device 140 can be configured to determine on a pixel-by- pixel basis whether each pixel within the image taken by the camera 125 has a color value (e.g., an RGB, CMYK, HSV, HSL, or HEX value, etc.) within a predetermined range (e.g., from yellow to green, corresponding with fluorescence of the dyed fluid 135). If a pixel has a color value outside of the predetermined range, the electronic device 140 can ignore the pixel (e.g., does not mark the pixel as indicating the presence of the dyed fluid 135) as an unmarked pixel 214. However, if the electronic device 140 determines that a pixel has a color value within the predetermined range, the electronic device 140 can mark the pixel as a marked pixel 216, indicating a potential leak. As should be appreciated, the electronic device 140 may complete the above steps regarding pixel determination for each and every pixel in the images taken by the camera 125. Thus, the electronic device 140 may analyze each side of the valve 1 15 to determine whether or not a leak is present.

[0048] At stage 430, the electronic device 140 can determine the presence of a leak in the valve 115. For example, the electronic device 140 can determine whether the valve has a leak based on a quantity of the marked pixels 216. More specifically, if the total number of the marked pixels 216 at stage 425 does not indicate the presence of the dyed fluid 135, due to being below a predetermined pixel count, the electronic device 140 can determine that no leaks are present and the valve 115 passes the leak detection test. However, if the number of the marked pixels 216 indicates a potential leak, due to being above the predetermined pixel count, the electronic device 140 can determine that the valve 115 has failed the leak detection test. Correspondingly, at stage, 435 the electronic device 140 can indicate whether the valve has passed or failed the leak detection test (e.g., that a leak is present in the region of valve 115 captured in the image). The indication that the valve 115 has failed the leak detection test can be provided in a number of ways, including, for example, an audible or visual alert. In somecases, a visual indication of the presence or location of a leak can be displayed on a screen of the electronic device 140 to indicate leak testing failure to an operator. In some cases, the indication can show an operator the approximate location of the leak in the valve 1 15.

[0049] FIG. 5 illustrates another example of a method 500 for operating the leak detection system 100. As will be recognized, the method 500 shares a number of components in common with and operates in a similar fashion to the examples illustrated and described previously. For the sake of brevity, these common features will not be again described below in detail. Rather, previous discussion of commonly named or numbered features, unless otherwise indicated, also applies to example configurations of the method 500.

[0050] At stage 540, for the images taken at stage 420, the electronic control device 140 can be configured to, on a pixel-by -pixel basis, apply either a first mastering color 310 or a second mastering color 314 to the pixels based on a color value of the pixel corresponding to the presence of the dyed fluid 135. For example, as illustrated in FIG. 9, if the electronic device 140 determines that a pixel 308 does not have a color value within a first color value range corresponding to a color of the dyed fluid 135, the electronic device 140 can turn the pixel 308 a first mastering color 310 (e.g., black, or as illustrated in FIG. 9. white) that indicates an absence of the dyed fluid 135. Correspondingly, if the electronic device 140 determines that the pixel 308 does have a color value within the first color value range corresponding to a color of the dyed fluid 135, the electronic device 140 can turn the pixel 308 a second mastering color 314 (e.g., yellow, or as illustrated in FIG. 9, black) that indicates presence of the dyed fluid 135. As should be appreciated, this bi-colored system of pixel modification (e.g., making the pixel 308 either the first or the second mastering color 310, 314 based on the perceived presence of dyed fluid 135) enables the electronic device 140 to create a simplified image of potential leak areas on the valve 115. Additionally, an operator may quickly identify potential leak areas based on the image created by the method 500.

[0051] Sill referring to FIG. 9, in some cases, to further simplify the mastered image created at stage 540, the electronic device 140 can be configured to group the pixels 308 with the second mastering color 314 that are within a predetermined distance from one another, at stage 545. That is. the electronic device 140 can group the pixels 308 having the second mastering color 314 according to their proximity to other pixels 308 having the second mastering color 314. For example, a group 318 (e.g., illustrated in FIG. 9 as having one or more cross-hatching patterns) can be formed by grouping all of the pixels 308 with the second mastering color 314 that are within five (5) of the pixels 308, or another predetermined distance, from each other. In such examples, the group 318 may also include all of the pixels308 having the first mastering color 310 that are within five (5) of the pixels 308, or another predetermined distance, from the pixels 308 of the group 318 having the second mastering color 314. Additionally, in such examples, the pixels 308 having the first mastering color 310 determined to be within the group 318, may be changed to the second mastering color 314, or to a third mastering color.

[0052] In other examples, the group 318 may include pixels 308 having the second mastering color 314 that are spaced further or nearer than five (5) pixels from each other, based on a resolution of the camera. For example, a higher resolution camera may group pixels 308 into the group 318 having the second mastering color 314 that are further than 5 pixels distance, whereas a lower resolution camera may group pixels 308 having the second mastering color 314 that are nearer than 5 pixels distance. Additionally, it is appreciated that the group 318 may include pixels 308 having the first mastering color 310 that are spaced further or nearer than five (5) pixels from a pixel having the second mastering color 314, based on a resolution of the camera. Accordingly, it is appreciated that, a “group” 318 of the pixels 308 as used herein is defined as a set of pixels 308 that can include one or more pixels 308.

[0053] At stage 550, the electronic device 140 determines the presence of a leak in the valve 115. More specifically, the electronic device 140 can determine the presence of dyed fluid in the images, which may indicate the presence of a leak. The presence of dyed fluid can be determined based on the groups 318 formed at stage 540. For example, referring again to FIG. 9. for each of the groups 318. the electronic controller 140 can be configured to count the total number of pixels 308 having the second mastering color 314 within the group 318. In other examples, the electronic controller 140 can be configured to count the total number of pixels 308 having the first mastering color 310 or the second mastering color 314 within the group 318. If the number of pixels 308 counted within the group 318 is below a predetermined value, the electronic device 140 can determine that no dyed fluid is associated with that group 318, and thus no leak is associated with that group 318. In some cases, if a group is not associated with dyed fluid, the group 318 can be ignored or removed, for example, and the pixels 308 in the group 318 can be modified to contain only the first mastering color 310. However, if the number of pixels 308 counted within the group 318 is at or above the predetermined value, then the electronic device 140 can determine that the group 318 corresponds with the presence of dyed fluid, and thus a potential leak is associated with that group 318. If any of the groups 318 have been associated with a potential leak, the electronic controller 140 can indicate that the valve 115 has failed the leak detection test at stage 435. Otherwise, the electronic controller 140 can indicate that the valve 115 has passed the leakdetection test. In some examples, the predetermined value of the number of pixels 308 counted in the group 318 may be about 100 pixels. In other examples, the predetermined value may be about 50 pixels, about 150 pixels, or about 200 pixels. However, similar to above, the predetermined value may be higher for a higher resolution camera and may be lower for a lower resolution camera.

[0054] FIG. 6 illustrates another example of a method 600 for operating the leak detection system 100. As will be recognized, the method 600 shares a number of components in common with and operates in a similar fashion to the examples illustrated and described previously. For the sake of brevity, these common features will not be again described below in detail. Rather, previous discussion of commonly named or numbered features, unless otherwise indicated, also applies to example configurations of the method 600.

[0055] In the method 600 shown in FIG. 6, the leak detection system 100 completes a two- stage process configured to prevent or reduce the inadvertent misidentification of dyed fluid 135 that may have accidentally spilled and / or otherwise been applied to one or more surfaces of the valve 115, which may give a false indication of a leak of the valve 115. For example, if a valve has previously failed a leak test and is being re-tested following a repair, the exterior of the valve may already be covered in some of the dyed fluid 135. Similarly, dyed fluid 135 may drip onto the exterior of a valve when being connected to the system 100. To address these possibilities, the electronic device 140 may use and compare before and after photos of the valve 115 (e.g., before and after pressurization with dyed fluid 135) to determine whether or not a leak is present.

[0056] In accordance with the method 600, once the valve 115 has been secured to the test station at stage 405, the electronic device 140 may confirm at stage 615 that the valve 115 is not pressurized with the dyed fluid 135. For example, the electronic controller 140 can communicate with a pressure sensor configured to measure an internal pressure of the valve115. If the internal pressure of the valve 115 is below a predetermined pressure, the electronic controller 140 can determine that the valve 115 is not pressurized. In some examples, the test station 110 may provide a supply pressure to the valve 115 using a pump 116. In such examples, the test station may determine the internal pressure of the valve 1 15 using a pressure sensor connected to the pump 11 , or otherwise connected between the valve 115 and the pump116. Specifically, the supply pressure of the fluid supplied by the pump 116 may be similar or identical to the internal pressure of the valve 115 and may therefore be measured to determine the internal pressure of the valve.

[0057] At stage 620, the camera 125 may take a first image 322 of the valve 115 in the unpressurized state to establish a baseline level of dyed fluid 135 present on the valve 115. It is appreciated that the first image 322 may include multiple images of the valve 115, as similarly described above with respect to stage 540. For example, the camera(s) may capture 10 to 50 images of the valve 115 at each camera position to account for noise and / or other potential errors.

[0058] Following this, at stage 640. the electronic device 140 may apply a first or second mastering color 310, 314 to the pixels 308 in the first image 322 based on a color value of each pixel corresponding to the dyed fluid 135, as similarly described above with respect to stage 540. Then, at stage 645, the electronic controller can group the pixels 308 in the first image 322 with the second mastering color 314 that are within predetermined distance from one another, as similarly described above with respect to stage 545. At stage 550, the groups 318 from the first image 322 can be analyzed to determine the presence of dyed fluid associated with those groups 318 prior to pressurization with the dyed fluid 135. For example, referring briefly to FIG. 10, for each of the groups 318 in the first image 322. the electronic controller 140 can be configured to count the total number of the pixels 308 having the second mastering color 314 within the group 318 (or, as described above, the total number of pixels 308 having the first mastering color 310 or the second mastering color 314 within the group 318). If the number of pixels 308 counted within the group 318 is below a predetermined value, the electronic device 140 can determine that no dyed fluid is associated with that group 318, and thus, the group 318 can be ignored or removed, for example, the pixels 308 in the group 318 can be removed from memory or the group 318 can be modified to contain only the first mastering color 310. However, if the number of pixels 308 counted within the group 318 is at or above the predetermined value, then the electronic device 140 can determine that the group 318 corresponds with the presence of dyed fluid, and the group 318 can remain. As should be appreciated, by indicating the presence or location of dyed fluid present on the valve 115 prior to pressurization of the valve 115, the electronic device 140 may help to differentiate between dyed fluid leaks and dyed fluid spillage and avoid false positive leak testing. As described above, the predetermined value of the number of pixels 308 counted in the group 318 may be about 100 pixels. In other examples, the predetermined value may be about 50 pixels, about 150 pixels, or about 200 pixels. However, the predetermined value may be higher for a higher resolution camera and may be lower for a lower resolution camera.

[0059] Referring again to FIG. 6, after establishing the baseline of dyed fluid on the valve 115 at stage 650, the valve 115 can be pressurized with the dyed fluid 135 at stage 415. Asmentioned previously, the valve 115 may be pressurized up to a predetermined value based on an intended use case of the valve. In one particular example, the valve 115 may be pressurized up to 250 BAR. Once the valve 1 15 is pressurized with dyed fluid 135, the camera 125 can take a second image 326 of the valve 115 at stage 655. The second image can include multiple images of the valve. For example, the second image 326 may include 10 to 50 images of the valve at each location. In some cases, the second image 326 can be taken in the same locations as the first image 322 were previously taken, which may be beneficial in comparing the first image 322 with the second image 326 at later stages in the method.

[0060] At stage 660, the electronic device 140 may apply a first or second mastering color 314 to the pixels 308 in the second image 326 based on a color value of each of the pixels 308 corresponding to the dyed fluid 135, as similarly described above with respect to stage 540. For example, referring again to FIG. 9, if the electronic device 140 determines that a pixel 308 does not have a color value within a second color value range corresponding to a color of the dyed fluid 135, the electronic device 140 can turn the pixel 308 the first mastering color 310, and if the electronic device 140 determines that the pixel 308 does have a color value within the second color value range, the electronic device 140 can turn the pixel 308 the second mastering color 314. In some cases, the first color value range and the second color value range can be the same. In other cases, the first color value range and the second color value range can be different. For example, the second color value range can be larger (e.g., to include a larger color gamut) or smaller (e.g., to include a smaller color gamut) than the first color value range. Correspondingly, the second value color range can be calculated based on the first color value range and a color value tolerance. Increasing the second color value range may reduce the possibility of false negatives (e.g., a false report that the valve 115 had passed the testing).

[0061] Then, at stage 665, the electronic controller 140 can group pixels 308 in the second image 326 with the second mastering color 314 that are within a predetermined distance from one another, as similarly described above with respect to stage 545. At stage 670, the groups 318 from the second image 326 can be analyzed to determine the presence of dyed fluid associated with those groups 318 after pressurization with the dyed fluid 135, as similarly described above with respect to stage 650. In this way. the electronic device 140 can determine the amount of dyed fluid present on the valve 115 after pressurization of the valve 115.

[0062] At stage 675, the electronic device 140 can compare the first image 322 and the second image 326 to determine the presence of a leak in the valve 115. More specifically, the electronic device 140 can be configured to compare at least a location and size of each of the groups 318 from the second image 326 with the groups in the first image 322. Additionally, ifa group 318 in the second image 326 does not have a corresponding group 318 in the first image 322 (e.g., at the location of the group 318 in the second image 326, there is no group at that same or similar location in the first image 322), the electronic controller 140 can determine that the group 318 in the second image 326 only appeared after the valve 115 was pressurized. Accordingly, the electronic controller 140 can determine that the group 318 in the second image 326 is indicative of a leak in the valve 11 .

[0063] Still refernng to FIG. 10. in some examples, a relative location of a group within an image may be associated with a centerpoint of the group 318. In order to compare locations of groups 318 in the first and second images 322, 326, the electronic controller 140 can compare a location of a center of mass (e g., a centerpoint of a group) or a centermost pixel of a group 318 in the first image 322 and a location of a center of mass or a centermost pixel of a group 318 in the second image 326. In some situations, the dyed fluid 135 may have flowed or otherwise moved a small distance between the taking of the first image and the second image. In order to account for such movement or flow of the dyed fluid 135, the electronic controller 140 may measure a distance between the location of the centermost pixel of the groups 318 in the first image 322 and the location of the centermost pixel of the groups 318 in the second image 326. In some examples, if the distance between a location of a centermost pixel of the group(s) 318 in the first image 322 and a location of a centermost pixel of the group(s) in the second image 326 is less than a predetermined distance (e.g.. about 50 pixels), the group 318 in the second image 326 may correspond to the group 318 in the first image 322 (e.g., at the location of the group 318 in the second image 326, there is a group 318 at that same or similar location in the first image 322).

[0064] In some examples, if the group 318 in the second image 326 does have a corresponding group in the first image 322 (e.g., at the location of the group 318 in the second image 326 there is also group at that same or similar location in the first image 322), the electronic controller 140 can compare the size of the two groups 318 to determine whether a leak is present at that location on the valve 115. Specifically, if the number of pixels 308 in the group 318 from the second image 326 is greater than the number of pixels 308 in the corresponding group 318 in the first image 322 by a predetermined amount, the electronic controller 140 can determine that the group 318 in the second image 326 is indicative of a leak in the valve 115. The predetermined amount can be a predetermined number of pixels or a predetermined multiplier, such as about 1.05, about 1.15, about 1.3. about two (2), about three (3). or about four (4) times the number of pixels 308 in the group in the first image. However, if the number of pixels 308 in the group 318 from the second image 326 is not greater than thenumber of pixels 308 in the corresponding group 318 in the first image 322 by the predetermined amount, the electronic controller 140 can determine that the group 318 in the second image 326 is not associated with a leak in the valve 115. For example, while the group 318 might grow in size between the first image 322 and the second image 326, the increase in size may be attributable to the natural dispersion or spread of dyed fluid 135 on the surface of the valve 115, and not an active leak in the valve 115.

[0065] Refernng again to FIG. 6, once the presence of leaks has been determined at stage 675, the electronic controller can indicate whether the valve 115 has passed or failed the leak detection test at stage 435.

[0066] FIGS. 7A-7D illustrate another example of a method 700 for operating the leak detection system 100. As will be recognized, the method 700 shares a number of components in common with and operates in a similar fashion to the examples illustrated and described previously. For the sake of brevity, these common features will not be again described below in detail. Rather, previous discussion of commonly named or numbered features, unless otherwise indicated, also applies to example configurations of the method 700.

[0067] In the method 700. show n in FIGS. 7A-7D, at stage 708 the cameras 125 may take multiple images 328 of the valve 115 from the same location. For example, the cameras 125 may take two, three, four, five, ten, fifty, and / or more images 328 of the valve 115 from a single perspective (e.g., side view, top view, etc.). Following this, the electronic device 140 may review the images to determine the presence of dyed fluid 135 and process the images 328 as described previously. Specifically, the pixels having the color value in the predetermined range can be turned a second mastering color 314 (e.g., yellow), while the pixels having the color value outside the predetermined range can be turned a first mastering color 310 (e.g., black). However, at stage 718. and prior to grouping the pixels as described previously, the electronic device 140 may create a first new image array 330. As illustrated in FIG. 11, the first new image array 330 may be generated by the electronic device 140 by applying “OR” Boolean logic on the images 328 taken of the valve 115 at stage 708. Following this, the electronic device may group the “True" pixels in the first image array 330 in the way described previously (e.g.. via proximity). In some cases, the “True” pixels in the first image array 330 may include a one (1) corresponding to the color yellow (i.e., with the second mastering color 314) and the “False” pixels in the first image array 330 may include a zero (0, or as illustrated in FIG. 11, no data) corresponding to the color black (i.e.. with the first mastering color 310).

[0068] At stage 722. the electronic device 140 may create a second new image array 334 based on the individual photos taken of the valve 115. In one example, as illustrated in FIG.11, the second new image array 334 may be generated by the electronic device 140 by applying "AND" Boolean logic on the images 328 taken of the valve 115 at stage 708. At stage 724. the electronic device 140 may count the number of “True” pixels according to Boolean logic. Following this, at stage 726, the electronic device 140 may group the “True” pixels in the newly formed second image array 334 in groups 338 the way described previously (e.g., via proximity, as illustrated in FIG. 12).

[0069] Referring to FIG. 12. following this, the electronic device 140 may map pixel groups from the first and second image arrays 330, 334 over each other (e g., as an overlay 342 of the OR and AND generated images and corresponding pixel groups 338) at stage 728. At stage 730, the electronic device 140 may count the number of individual pixels within a singular AND (second image array) group 338. If the number of pixels in the AND pixel group is greater than a predetermined value, the electronic device may mark the pixel group as containing dyed fluid 135 at 732. At 730 the electronic device 140 may apply an exclusive or “XOR” Boolean logic to the group formed at stage 732 to create an XOR logic array 346. At stage 740, the electronic device 140 may count the number of individual pixels in the group formed by the XOR logic. At stage 742, the electronic device may divide the number of pixels in the XOR group by the number of pixels in the AND group. The electronic device may then save this fractional value as a threshold value between the XOR and the AND groups to be expected by the electronic device 140 for each pairing of pixel groups.

[0070] Following this, the electronic device 140 pressurizes the valve 115 via the dyed fluid 135 and performs the procedures described previously relating to comparison of the before pressurization and after pressurization pixel groups to determine whether or not the leak detection test is passed or failed.

[0071] In some implementations, devices or systems disclosed herein can be utilized, manufactured, or installed using methods embodying aspects of the invention. Correspondingly, any description herein of particular features, capabilities, or intended purposes of a device or system is generally intended to include disclosure of a method of using such devices for the intended purposes, a method of otherwise implementing such capabilities, a method of manufacturing relevant components of such a device or system (or the device or system as a whole), and a method of installing disclosed (or otherwise known) components to support such purposes or capabilities. Similarly, unless otherwise indicated or limited, discussion herein of any method of manufacturing or using for a particular device or system, including installing the device or system, is intended to inherently include disclosure, asembodiments of the invention, of the utilized features and implemented capabilities of such device or system.

[0072] Additionally, unless otherwise specified or limited, the terms '‘about” and “approximately,” as used herein with respect to a reference value, refer to variations from the reference value of ± 15% or less, inclusive of the endpoints of the range. Similarly, the term “substantially equal” (and the like) as used herein with respect to a reference value refers to variations from the reference value of less than ± 30%. inclusive. Where specified, “substantially” can indicate in particular a variation in one numerical direction relative to a reference value. For example, “substantially less” than a reference value (and the like) indicates a value that is reduced from the reference value by 30% or more, and “substantially more"’ than a reference value (and the like) indicates a value that is increased from the reference value by 30% or more.

[0073] Also as used herein, unless otherwise limited or specified, “substantially identical” refers to two or more components or systems that are manufactured or used according to the same process and specification, with variation between the components or systems that are within the limitations of acceptable tolerances for the relevant process and specification. For example, two components can be considered to be substantially identical if the components are manufactured according to the same standardized manufacturing steps, with the same materials, and within the same acceptable dimensional tolerances (e.g., as specified for a particular process or product).

[0074] The description of the different advantageous embodiments has been presented for purposes of illustration and description and is not intended to be exhaustive or limited to the embodiments in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. Further, different advantageous embodiments may provide different advantages as compared to other advantageous embodiments. The embodiment or embodiments selected are chosen and described in order to best explain the principles of the embodiments, the practical application, and to enable others of ordinary skill in the art to understand the disclosure for various embodiments with various modifications as are suited to the particular use contemplated.

Claims

CLAIMSWe claim:

1. A method of leak testing a valve, comprising: activating, via a controller, a camera and a light source; taking, via the camera, a first image of the valve; pressurizing the valve with a dyed fluid to a predetermined pressure value, the dyed fluid configured to emit a fluorescent glow in response to illumination via the light source; taking, via the camera, a second image of the valve in a pressurized state; comparing, via a processor, the first image of the valve with the second image of the valve; and detecting, via the processor, a leak when a fluorescent glow is detected in the second image.

2. The method of claim 1 , wherein the light source emits light at a first wavelength.

3. The method of claims 1 or 2, wherein the dyed fluid emits the florescent glow at a second wavelength in response to the illumination via the light source.

4. The method of any of claims 1 to 3, wherein the detecting, via the processor, the leak, includes: reviewing each pixel in the first image and the second image; and changing a color of one or more of the pixels to a first color based on the presence of fluorescent glow from the dyed fluid.

5. The method of claim 4, wherein the detecting, via the processor, the leak, includes: grouping, via the processor, a number of pixels in both the first image and the second image into a first group and second group, respectively, based on the color of the pixels; and mapping, via the processor, the second image of the valve onto the first image of the valve.

6. The method of claim 5, further comprising: calculating, via the processor, the number of pixels in the first group; calculating, via the processor, the number of pixels in the second group; and comparing, via the processor, the number of pixels in the first group to the number of pixels in the second group.

7. The method of claim 6, further comprising: indicating a leak is present when the number of pixels in the second group is larger than a number of pixels in the first group by a predetermined factor.

8. The method of claim 6, further comprising: indicating no leak is present when the number of pixels in the second group is smaller than a number of pixels in the first group multiplied by a predetermined factor.

9. The method of any of claims 1 to 8, further comprising moving the camera with robotic arm that is controlled by the processor.

10. A non-transitory machine-readable storage medium encoded with instructions executable by a processor, the machine-readable storage medium comprising instructions to, when executed by the processor, cause the processor to: activate a camera and a light source; take a first image of a valve via the camera; pressurize the valve with a dyed fluid to a predetermined pressure value, the dyed fluid to give off a fluorescent glow in response to illumination via the light source; take a second image of the valve after pressurization of the valve; compare the first image of the valve to the second image of the valve; and detect a leak when fluorescent glow is detected in the second image.

11. The non-transitory machine-readable storage medium of claim 10, wherein the processor groups a number of pixels in both the first image and the second image of the valve into a first image group and a second image group, respectively, based on the presence of fluorescent glow from the dyed fluid, and maps the second image of the valve onto the first image of the valve.

12. The non-transitory machine-readable storage medium of claim 11, wherein the processor: counts the number of pixels in the first image group; counts the number of pixels in the second image group; and compares the number of pixels in the first image group to the number of pixels in the second image group.

13. The non-transitory machine-readable storage medium of claim 12, wherein the processor: compares a location of the first image group to a location of the second image group, and determines the location of the first image group is similar to the location of the second image group.

14. The non-transitory machine-readable storage medium of claims 12 or 13, wherein the processor: indicates a leak is present when the number of pixels in the second image group is larger than a number of pixels in the first image group.

15. The non-transitory machine-readable storage medium of any of claims 12 to 14, wherein the processor: indicates no leak is present when the number of pixels in the second image group is smaller than a number of pixels in the first image group.

16. The non-transitory machine-readable storage medium of any of claims 11 to 15, wherein the processor: changes a color of one or more of the pixels to a first color based on the presence of fluorescent glow from the dyed fluid, and groups the one or more pixels based on color and proximity relative to one another.

17. A system for detecting a leak in a valve, the system comprising: a stand configured to hold the valve; a light source configured to emit a light onto the valve; a pump that is configured to supply a fluid to the valve to pressurize the valve, the fluid including a dye that fluoresces in response to the light emitting by the light source; a camera configured to take images of the valve; and a processor configured to: activate the light source to emit the light on the valve, control the camera to take a first image of the valve in an unpressurized state, control the cameral to take a second image of the valve in a pressurized state, and compare the first image with the second image and determine a presence of a leak based on whether a fluorescent glow of the fluid is detected in the second image.

18. The system of claim 17, wherein the light source and the camera are coupled to a robotic arm and the processor is configured to control operation of the robotic arm.

19. The system of claim 18, wherein the first image and the second image are taken at a first position of the robotic arm and the processor is further configured to take of a third image of the valve in an unpressurized state and a fourth image of the valve in a pressurized state, the third image and the fourth image taken at a second position of the robotic arm that is different from the first position.

20. The system of any of claims 17 to 19, wherein the processor is further configured to operate the pump to supply the fluid to the valve.

Images