System and method for automatically detecting coating defects

Abstract

A system and method for automatically detecting defects in a coating of a component is provided. In one aspect, a coating inspection system is provided. The coating inspection system includes a heating element operable to impart heat to the component as it traverses relative to the component. An imaging device of the system captures an image of the component as the heating element traverses relative to the component and applies heat thereto. The image indicates a transient thermal response of the component. The system can generate a single observation image using the captured image. The system can detect and analyze defects using the generated single observation image.

Description

Technical Field

[0001] The present subject matter generally relates to systems and methods for automatically detecting defects in coatings, such as coatings used on turbomachinery components. Background Art

[0002] Some components used in power and aviation gas turbine engines are coated with thermal barrier coatings, especially those located along the hot gas path of such engines. For example, metal turbine blades are often coated with thermal barrier coatings to protect the metal structure of the blades from thermal damage during operation. Bond coatings are often provided between the metal structure and the thermal barrier coating to enhance the bond or adhesion between them. In general, thermal barrier coatings can increase the effective service life of metal high temperature components.

[0003] Detection of defects in thermal barrier coatings can ensure that only components with satisfactory coatings can be assembled on the engine. Therefore, these components are usually inspected for defects. The formation of coating defects may occur during coating processes (e.g., electron beam physical vapor deposition (EBPVD) coating processes). Common coating defects include spatters and pits. When too much coating material is deposited in a local area, spatters may form. Among other disadvantages, spatters disrupt the flow of fluid through the engine. During the coating process, or in some cases, during engine operation, pits may also be formed. Pits are voids or spaces in the coating. If the spatters and / or pits in the thermal barrier coating exceed a certain size, depth, number, area fraction, or some combination thereof, the coating may need to be stripped and the component may need to be recoated. Coating rework may be expensive, time-consuming, and generally inconvenient.

[0004] Existing techniques for identifying defects in thermal barrier coatings are largely visual and done manually by operators. Furthermore, these techniques are subjective and not quantitative. As a result, when using existing techniques, some parts that should be stripped and recoated pass quality inspection, while some parts with satisfactory thermal barrier coatings do not pass quality inspection and are stripped and recoated. As a result, resources are wasted and additional costs are incurred.

[0005] Therefore, systems and methods that address one or more of the challenges described above would be useful. In particular, improved systems and methods for evaluating the quality of thermal barrier coatings used in high temperature applications would be beneficial. Summary of the invention

[0006] Aspects of the present disclosure relate to a distributed control system and method for controlling a turbine. Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.

[0007] In one aspect, a system is provided. The system includes a heating element, an imaging system having an imaging device, and a computing system having one or more processors and one or more memory devices. The one or more processors are configured to: cause the heating element to traverse relative to a component having a coating; cause the heating element to heat the component as the heating element traverses relative to the component; cause the imaging device to capture multiple images of the component as the heating element traverses relative to the component and applies heat thereto, the multiple captured images indicating a transient thermal response of the component; and detect one or more coating defects in a coating of the component based at least in part on the transient thermal response of the component captured in the multiple images.

[0008] In another aspect, a method is provided. The method includes traversing a heating element relative to a component having a coating. The method also includes heating the component with the heating element as the heating element traverses relative to the component. Additionally, the method includes capturing a plurality of images of the component using an imaging device as the heating element traverses relative to the component and applies heat thereto, the captured plurality of images indicating a transient thermal response of the component. Additionally, the method includes detecting one or more coating defects in a coating of the component based at least in part on the transient thermal response of the component captured in the plurality of images.

[0009] In a further aspect, a non-transitory computer-readable medium is provided. The non-transitory computer-readable medium includes computer-executable instructions that, when executed by one or more processors of a computing system of a coating inspection system, cause the one or more processors to: cause a heating element of the coating inspection system to traverse relative to a component having a coating; cause the heating element to heat the component as the heating element traverses relative to the component; cause an imaging device of the coating inspection system to capture a plurality of images of the component as the heating element traverses relative to the component and applies heat thereto, the plurality of captured images indicating a transient thermal response of the component; and detect one or more coating defects in a coating of the component based at least in part on the transient thermal response of the component captured in the plurality of images.

[0010] These and other features, aspects and advantages of the present invention will be better understood with reference to the following description and appended claims.The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the subject matter and, together with the description, serve to explain the principles of the subject matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] A full and enabling disclosure of the present invention, including the best mode thereof, to one of ordinary skill in the art is set forth in the specification with reference to the accompanying drawings, in which:

[0012] Figure 1 A perspective view of a coating inspection system according to one embodiment of the present disclosure is provided;

[0013] Figure 2 Provided by Figure 1 a close-up schematic cross-sectional view of a portion of a component inspected by a system;

[0014] Figure 3 Provided Figure 1 A flowchart of an example method by which a system may perform a coating inspection process on a component;

[0015] Figure 4-7 Provided Figure 1 The heating element of the system is relative to Figure 1 A schematic diagram of a component traversed by a heating element as heat is applied to the component;

[0016] Figure 8 Provided Figure 4-7 A close-up view of a heating element traversing and heating a component;

[0017] Fig. 9 A schematic diagram of a single image of a component generated from multiple captured images is provided;

[0018] Fig.10 A method for detecting defects is provided Fig. 9 A close-up view of a portion of a single image;

[0019] Fig.11 Provides an alternative method of detecting defects Fig. 9 Close-up view of a single image of;

[0020] Fig.12 A graph depicting a time-temperature curve of a pixel according to one embodiment of the present disclosure is provided;

[0021] Fig.13 Provided Figure 1 A block diagram of a computing system of a coating inspection system;

[0022] Fig.14 A flowchart of an example method of generating a single observation image according to one embodiment of the present disclosure is provided;

[0023] Figure 15-18 providing a view of a plurality of images of a component captured by an imaging device as a heating element traverses relative to the component in a traverse direction and applies heat thereto;

[0024] Fig.19 A schematic diagram of the thermal data of the pixels of the masking window applied to each image is provided;

[0025] Fig. 20 A schematic diagram of a plurality of generated mask images according to an embodiment of the present disclosure is provided;

[0026] Fig.21 provides an illustration of an image of a component captured by an imaging device as a heating element traverses relative to the component in a traversing direction and applies heat thereto, and also depicts one example manner in which a masking window may be positioned relative to the heating element;

[0027] Fig. 22 provides an illustration of an image of a component captured by an imaging device as a heating element traverses relative to the component in a traversing direction and applies heat thereto, and also depicts another example manner in which a masking window may be positioned relative to the heating element;

[0028] Fig.23 depicts several masked images according to one embodiment of the present disclosure; and

[0029] Fig.24 A single observed image having multiple pixels is depicted according to one embodiment of the present disclosure. DETAILED DESCRIPTION

[0030] Reference will now be made in detail to the present embodiments of the present invention, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical and letter names to refer to the features in the drawings. The same or similar names have been used to refer to the same or similar parts of the present invention in the drawings and description. As used herein, the terms "first", "second" and "third" are used interchangeably to distinguish one component from another and are not intended to represent the location or importance of the various components. The terms "upstream" and "downstream" refer to the relative flow direction relative to the flow of a fluid in a fluid path. For example, "upstream" refers to the flow direction from which a fluid flows, and "downstream" refers to the flow direction to which a fluid flows.

[0031] In general, the present disclosure provides systems and methods for detecting defects in coatings used on components of turbomachinery, such as aviation and power gas turbine engines. The system includes features that improve the detectability of defects in coatings, such as splatters and pits, with better accuracy than conventional systems / techniques. The systems and methods of the present disclosure may provide a faster, more accurate, and non-contact method of determining the quality of component coatings, such as thermal barrier coatings (TBCs) of metal turbine blades.

[0032] In one aspect, a coating inspection system for automatically detecting defects in a barrier coating of a component is provided. For example, the component may be a metal component of a gas turbine engine and the barrier coating may be a non-conductive coating, such as a thermal barrier coating. The coating inspection system includes a heating element for imparting heat to the component. The heating element may be movable relative to the component. In this way, the heating element may traverse relative to the component when the heating element applies heat to the component. The component may be fixed in place by a platform system. The system also includes an imaging device for capturing an image of the thermal response of the component when the heating element traverses relative to the component and applies heat thereto. For example, the imaging device may be an infrared (IR) imaging device (e.g., an IR camera). It is noteworthy that when the heating element traverses and heats the component, a transient thermal gradient is generated between the non-defective area and the defective area of ​​the barrier coating due to the difference in the heat radiated outward from the non-defective area of ​​the coating and the heat radiated outward from the defect in the barrier coating. The imaging device may capture these transient thermal responses. The imaging device may capture transient thermal responses when the heating element actively heats the component and / or when the component cools after being heated. By heating the component by 10-15 degrees Fahrenheit or more relative to ambient temperature, transient thermal gradients can become significant.

[0033] The system also includes a computing system having one or more processors and one or more memory devices. The computing system is communicatively connected to the imaging device and the heating element. The one or more processors are configured to cause the heating element to traverse relative to the component and cause the heating element to heat the component when the heating element traverses relative to the component. Traversing the heating element causes the component to exhibit a transient thermal response as described above. The one or more processors are also configured to cause the imaging device to capture multiple images of the component when the heating element traverses relative to the component and applies heat thereto. In this way, the captured images indicate the thermal response of the component. The one or more processors can detect one or more coating defects in the barrier coating of the component based at least in part on the thermal response of the component captured in the multiple images. In some embodiments, the one or more processors can generate a single observation image from multiple captured images so that the thermal response of the component (or a specific viewing angle or orientation of the component) is represented in a single image. This can facilitate the detection of defects and the analysis of the thermal response of the component.

[0034] Furthermore, in some embodiments, the computing system is communicatively coupled to the airflow generator. The one or more processors can cause the airflow generator to pulse air into one or more internal passages of the component. This can enhance the thermal response of the component, making the thermal response of the component more easily captured by the imaging device. A method of automatic defect detection in a non-conductive coating of a component is also provided.

[0035] Thus, the systems and methods described herein exploit the transient nature of the thermal response of a component to detect spatters and pits in a non-conductive coating of a component. In summary, as a heating element traverses relative to a particular section of a component, a current is induced in the conductive substrate of the section by directing a pulsed alternating current (AC) through the heating element (e.g., for a few seconds), which in turn generates heat in the conductive substrate that radiates through the non-conductive coating. The thermal response of the component or that particular section of the component is detected by a high-speed imaging device (e.g., an IR camera). In particular, the transient thermal field interacts with defects in a section of the component, resulting in local thermal contrast differences or gradients that can be imaged or captured by the IR camera. As the heating element traverses relative to the component and applies heat to it, the IR camera can capture the local thermal response of some or all sections of the component.

[0036] Advantages of the present system and method include improved detectability and the ability to quantify defects by enhancing contrast at the defect due to the transient nature of the inspection. Notably, the transient nature of the inspection improves the detectability of smaller defects that are not detectable using existing IR thermal imaging methods and / or steady-state heating methods. For example, using the present system and method, splatters and pits as small as 10 mils in the coating are detectable. Specifically, splatters and pits of 10 mils to 7 mils can be detected. Compared to conventional systems and methods, the detection of such small defects is made possible due to the generation of transient thermal gradients. The transient thermal gradient enhances the contrast between defective and non-defective areas of the coating of the component in the captured image.

[0037] Various parameters can affect the detectability and quantification of defects. For example, one parameter that can affect the detectability of defects is the frame rate of the imaging device (e.g., an IR camera). A higher frame rate allows transient thermal gradients at the defect to be captured with better thermal contrast, especially when detecting smaller defects (e.g., less than 10 mils), because thermal gradient changes near small defects tend to disappear faster. In some example embodiments, the imaging device of the coating inspection system has a frame rate of at least 60 Hz. In some embodiments, the imaging device of the coating inspection system has a frame rate between 60-500 Hz. In some embodiments, the imaging device of the coating inspection system has a frame rate between 250-500 Hz.

[0038] Another parameter that can affect the detectability of defects is the spatial resolution of the imaging device. In some embodiments, the imaging device has a spatial resolution such that the imaging device is operably configured to detect defects or features as small as 80 microns (or approximately 0.003 inches). In such an embodiment, for example, the imaging device can have a 25 mm lens and a 640X512 pixel detector IR camera. The working distance between the IR detector and the component can be set to 6 inches. In other embodiments, the imaging device can detect defects or features less than 80 microns (or approximately 0.003 inches) by using a 1024X1024 pixel detector IR camera and / or by reducing the working distance between the IR detector and the component (e.g., to less than 6 inches (depending on the minimum working distance requirements of the lens and the IR detector)).

[0039] A further parameter that may affect the detectability of defects is the wavelength of the imaging device. In some example embodiments, the imaging device is a medium wave IR camera (e.g., 3-6 μm). In some example embodiments, the imaging device is a long wavelength IR camera (e.g., 7-14 μm). In some embodiments, the imaging device is one of at least two imaging devices of the system. At least one imaging device may be a medium wave IR camera (e.g., 3-6 μm) and at least one imaging device may be a long wavelength IR camera (e.g., 7-14 μm). Another parameter that may affect the detectability of defects is the thermal sensitivity of the imaging device. In some example embodiments, the thermal sensitivity of the imaging device (e.g., IR camera) is between 18-50 mK. This range allows for detection of smaller temperature differences or less steep gradients, and therefore, an imaging device having a thermal sensitivity range between 18-50 mK provides an enhanced ability to detect smaller defects.

[0040] Another parameter that can affect the detectability of defects is the speed of the heating element. That is, the speed and direction of the heating element relative to the stationary component is a parameter that affects detectability. In some embodiments, as described above, the heating element (e.g., an energized induction coil) moves or traverses relative to the stationary component. On the one hand, if the speed of the heating element is too slow, the component and its coating may reach or approach a steady-state condition. That is, if the speed of the heating element is too slow, the component will become uniformly heated, which will have an adverse effect on the detection of defects because transient thermal gradients are "washed out" by the uniform heating of the component. On the other hand, if the speed of the heating element is too fast, the thermal contrast near the defect may not be generated to a sufficient degree for detection. In addition, the faster the heating element traverses relative to the component, the faster the frame rate of the imaging device needs to be to capture the thermal gradient. In some example embodiments, the speed at which the heating element traverses or moves relative to the component to detect splashes and pits is between 2-5cm / s.

[0041] Other parameters that may affect the detectability of defects include heating rate and heating duration. The heating rate is directly affected by the speed of the heating element relative to the component (see above) and the current characteristics (e.g., the frequency of the AC current) directed to the heating element. The heating duration depends on the size of the component (e.g., the thickness of the substrate of the component). If the heating duration is too long, the transient thermal gradient will be washed away. If the duration of heating the component is too fast, the imaging device may not be able to capture the gradient. In addition, in some embodiments, the imaging device includes a detector that measures counts. The counts per period of time represent the temperature measurement of the target surface. In such an embodiment, a component (e.g., a turbine blade with a TBC) can be heated at a rate of 45 counts / second-300 counts / second. The heating rate is a function of the thickness of the part, the conductivity of the material, and the thickness of the coating. Typically, for example, thinner areas heat faster than thicker areas. The component can be cooled at a rate of 45 counts / second-300 counts / second.

[0042] On the other hand, systems and methods for generating a single observation image from multiple captured images are provided. That is, all local thermal transients captured by an imaging device in multiple images or videos can be compiled into a single summary image. In particular, during coating inspection of a component with a barrier coating, the imaging device can capture an image of the component as a heating element traverses relative to the component and applies heat to it. For example, the imaging device can be an infrared imaging device. The captured images (e.g., collectively referred to as IR videos) are received by one or more processors of a computing system. The received images capture the component from the same angle. In response to the heating element sweeping across and heating the component, the received image also captures the thermal distribution of the component.

[0043] One or more processors are configured to generate a plurality of masked images using the received captured images. Specifically, in some embodiments, the masking window is positioned adjacent to the heating element and in front of it along the traverse direction in each captured image. In other embodiments, the masking window is positioned adjacent to the heating element and behind it along the traverse direction in each captured image. In other embodiments, the masking window includes two sections, including a front section and a rear section. In such an embodiment, the front section of the masking window is positioned adjacent to the heating element and in front of it along the traverse direction in each captured image, and the rear section of the masking window is positioned adjacent to the heating element and behind it along the traverse direction in each captured image. In such an embodiment, the front section and the rear section can be discontinuous sections. When the heating element moves frame by frame or image by image relative to the component, the masking window moves or positions frame by frame or image by image accordingly. The masking window masks pixels outside its periphery. In this way, pixels outside the masking window will be ignored.

[0044] Thermal data (e.g., temperature data) is applied to pixels within a masking window of each image. Thermal data can be applied to each pixel within a given masking window. Using the generated masking image, one or more processors determine the maximum or minimum value (e.g., maximum or minimum temperature value) of each pixel on the masking image. That is, all or some pixels can be represented in multiple masking images because the masking windows can be positioned so that they include some of the same pixels. One or more processors can consider the value (e.g., temperature value) of a specific pixel on multiple masking images and can determine the maximum or minimum value of the specific pixel. In other words, the maximum or minimum value associated with each pixel in the masking image is determined.

[0045] Once the maximum or minimum value is selected for each pixel on the masking image, a single observation image is generated. The pixels selected for inclusion in the two-dimensional single observation image are those that represent the maximum or minimum value of their respective pixels. Therefore, the single observation image depicts the thermal response in an enhanced and easily analyzed manner. In addition, since the pixels are selected from the pixels of the masking image, the heating element is not present in the single observation image. Therefore, although the imaging device captures the heating element traversing relative to the component to capture the transient thermal response when the heating element applies heat to the component, the single observation image does not include or only negligibly includes the heating element footprint. This can provide a clearer image and can facilitate analysis of the thermal response of the component.

[0046] System and method for automatically detecting defects in coatings of components

[0047] Reference now Figure 1 and Figure 2 , Figure 1 A perspective view of a coating inspection system 100 according to one embodiment of the present disclosure is provided. Figure 2 Provides the experience Figure 1 A close-up schematic cross-sectional view of a portion of a component 200 for coating inspection of the system 100. Generally, the system 100 is operably configured to detect defects in a barrier coating of a component. For example, the system 100 is operable to detect defects in a thermal barrier coating (TBC) of a metal component of a gas turbine engine, such as a turbine blade or vane of a nozzle. In addition, the system 100 is configured to detect various types of coating defects, including but not limited to spatter, pits, delamination, and other types of cracks and surface imperfections. Although the component 200 is described herein as a metal turbine blade for an aircraft gas turbine engine, it should be understood that the system 100 described herein is not limited to detecting defects in turbine blades, but is configured to detect defects in other types of metal components that also have a barrier coating.

[0048] exist Figure 1, component 200 is shown as being subjected to coating inspection by system 100. For this embodiment, component 200 is a high pressure turbine blade of an aircraft gas turbine engine. Figure 2 As shown, component 200 has a metal structure 210. For example, metal structure 210 may be formed of a nickel superalloy or other suitable high temperature metal material. Component 200 also has a metal bond coating 212 and a barrier coating 214. Metal bond coating 212 is disposed between an outer surface 215 of metal structure 210 and barrier coating 214. Thus, barrier coating 214 is an outer or top coating of component 200. Barrier coating 214 has an outer surface 216. Barrier coating 214 may be a non-conductive barrier coating. For example, barrier coating 214 may be a ceramic thermal barrier coating. Metal bond coating 212 promotes adhesion or bonding between barrier coating 214 and metal structure 210 of component 200. Metal bond coating 212 may be applied to metal structure 210 in any suitable manner. Likewise, barrier coating 214 may be applied to metal bond coating 212 in any suitable manner, such as by an electron beam physical vapor deposition (EBPVD) coating process.

[0049] like Figure 2 As further shown, the component 200 defines one or more interior or internal passages 218, such as one or more internal cooling passages. In addition, the component 200 defines one or more cooling holes 220. The one or more cooling holes 220 provide fluid communication between the internal passages 218 of the component 200 and the external environment. For example, when the component 200 is positioned within the hot gas path of a gas turbine engine, a cooling fluid may flow through the internal passages 218 and downstream through the cooling holes 220 and into the hot gas path. In this way, the component 200 may be cooled during operation of the gas turbine engine.

[0050] Return to Figure 1 , the system 100 will now be described in detail. For this embodiment, the system 100 includes a heating system 110, a platform system 130, an airflow generator 140, an imaging system 150, and a computing system 160. For reference, Figure 1 The system 100 defines a vertical direction V, a lateral direction L and a transverse direction T. The vertical direction V, the lateral direction L and the transverse direction T are perpendicular to each other and form an orthogonal direction system.

[0051] The heating system 110 of the system 100 includes one or more heating elements 112 that are operably configured to impart heat to a component under inspection. Figure 1As shown, one or more heating elements 112 are configured to heat a component 200. For this embodiment, the one or more heating elements 112 include an electric heating coil 114. For example, the heating coil 114 can be formed of copper or another suitable conductive material. The heating coil 114 can include or form a vortex or spiral heating portion 116, for example, at its distal end. The spiral heating portion 116 defines a heating zone 118, and the size of the heating zone 118 is designed to receive the component 200. That is, the size of the spiral heating portion 116 of the heating coil 114 is designed so that the component 200 can be received within the heating zone 118. In this way, the heating coil 114 can completely surround or surround the component 200. Assuming that multiple imaging devices are used, this can allow image capture of multiple sides of the component at the same time. In other embodiments, the heating coil 114 can have other suitable shapes or geometries for heating the component 200 during coating inspection.

[0052] refer to Figure 1 and 2 , the heating coil 114 is electrically connected to the power source 120. The power source 120 can be any suitable power source. For example, the power source 120 can be a battery, a line voltage, some combination thereof, etc. When the heating coil 114 is energized by the current provided by the power source 120, heat is radiated from the heating coil 114. The radiated heat can induce eddy currents in the metal structure 210 of the component 200. In this way, the heating coil 114 can inductively heat the component 200. Because the barrier coating 214 of the component 200 is a non-conductive coating in this example embodiment, the eddy currents do not flow through the barrier coating 214. Heat radiates outward from the metal structure 210 and the metal bond coating 212 through the barrier coating 214, and ultimately radiates to the outside of the component 200, as shown in FIG. Figure 2 As will be explained in more detail herein, different thermal responses are generated due to the difference in heat radiated or emitted outwardly from the non-defective area 232 of the barrier coating 214 and the heat radiated outwardly from the defect 230 or defective area in the barrier coating 214. The system 100 can sense or capture these transient thermal responses and detect defects in the barrier coating 214 accordingly.

[0053] The heating system 110 also includes a servo motor 122. When commanded (e.g., by one or more electrical signals received from a control device), the servo motor 122 can move the heating coil 114 relative to the component 200. Thus, the heating coil 114 can move relative to the component 200. In this example embodiment, the heating coil 114 can move relative to the stationary component 200 in a transverse direction T1. Figure 1, the transverse direction T1 extends along or parallel to the vertical direction V. Therefore, the heating coil 114 can inductively heat the component 200 as it traverses relative to the component 200 or on the component 200 along the transverse direction T1. In this way, the entire length of the component 200 can be inductively heated. It should be understood that the transverse direction T1 does not need to be parallel to or extend along the vertical direction V, and can also extend in other directions. It is worth noting that the heating coil 114 can traverse relative to the component 200 and apply heat to it without contacting the component 200.

[0054] By moving the heating coil 114 in the traversing direction T1 relative to the component 200, transient thermal gradients can be created and captured by the imaging system 150. The thermal gradients are transient because they are generated in an instant or relatively short period of time as the heating coil 114 traverses over and heats that particular area of ​​the component 200. Therefore, transient thermal gradients appear and disappear relatively quickly. Therefore, the thermal response of the component is transient because the captured response is time-sensitive to when the heating coil 114 traverses and heats the component 200 relative to the component 200.

[0055] In some alternative embodiments, the heating system 110 may be operably configured to generate a thermal gradient within the barrier coating 214 of the component 200 between the defect region 230 and the non-defect region 232. In such embodiments, various suitable types of heating elements may be used, including optical heating elements, laser heating elements, electromagnetic heating elements (e.g., microwave heating elements).

[0056] The platform system 130 of the system 100 includes a platform 132. For this embodiment, the platform 132 is a multi-axis platform that is movable along multiple axes. In particular, for this embodiment, the platform 132 is translatable along a vertical direction V, a lateral direction L, and a transverse direction T. The platform system 130 includes a component holder 134 or a bracket that is operable to hold the component 200 in place, for example, during inspection. In some embodiments, the component 200 can be manually loaded into and / or unloaded from the component holder 134. In other embodiments, a robotic arm or other automated device can load and / or unload the component 200 into and / or unload from the component holder 134. For Figure 1 In the illustrated embodiment, the component holder 134 is operably coupled to the platform 132 via a turntable 136. The turntable 136 is operable to rotate about an axis of rotation (e.g., a longitudinal centerline LC). In this way, the component holder 134 and the component 200 secured thereby can be rotated about the axis of rotation. Among other benefits, this can allow the component 200 to be oriented relative to the imaging device or the heating coil 114 during inspection.

[0057] In some embodiments, when commanded (e.g., by one or more electrical signals from a control device), the platform system 130 (e.g., via the multi-axis platform 132 and / or the turntable 136) is configured to move the component 200 relative to the heating coil 114. For example, the multi-axis platform 132 can initially position the component 200 relative to the heating coil 114, for example, so that the component 200 is centered or substantially centered along the longitudinal axis LC defined by the spiral heating portion 116 of the heating coil 114. In this manner, the heating coil 114 can be swept or traversed over the component 200 along the traverse direction T1 during the inspection process to inductively heat the component 200. The turntable 136 can be controlled to orient the component 200 to a desired orientation, for example, for inspecting a particular side of the component 200. In some alternative embodiments, the platform system 130 can be configured to move the component 200 relative to the heating coil 114 (e.g., via the platform 132 and the turntable 136), wherein the heating coil 114 is held or controlled to remain in a fixed position. Thus, in some embodiments, the component 200 may be moved by the stage system 130 relative to the stationary heating coil 114 .

[0058] In some embodiments, the system 100 optionally includes an airflow generator 140. For this embodiment, the airflow generator 140 is mounted to the platform system 130. However, in other embodiments, the airflow generator 140 is separate from the platform system 130. The airflow generator 140 can be operated to move air through, through, or otherwise around the component 200, for example, as the heating coil 114 traverses and heats the component 200. For example, Figure 2 As shown, the airflow generator 140 can move air through one or more internal passages 218 of the component 200. Thus, the airflow generator 140 is in fluid communication (e.g., airflow communication) with the internal passages 218 of the component 200. For example, one or more conduits can fluidly couple the airflow generator 140 with the internal passages 218 of the component 200. The conduits can be directed internally through the platform 132, the turntable 136, and the component holder 134, or can be directed externally to the internal passages 218 of the component 200.

[0059] In some embodiments, the airflow generator 140 can be configured to pulse air through one or more internal passages 218 of the component 200. In this way, improved detectability of defects (e.g., splatters and pits) can be achieved, especially around functionally important features. Functionally important features of a component can include, but are not limited to, the leading and / or trailing edges of a blade or nozzle, the tip of a blade, areas near cooling holes, etc. The airflow generator 140 can be controlled to pulse a certain amount of air at a predetermined frequency or interval. For example, the predetermined frequency can range from 10 -2 to 10 2Hz. The frequency selected from this range can promote the enhancement of the transient thermal response of the component 200. In addition, the airflow generator 140 can be controlled to provide a predetermined amount of air with each pulse. In some embodiments, ambient air can be drawn into the airflow generator 140 and pulsed into or through the component 200. In other embodiments, the airflow generator 140 is in fluid communication with a pressurized air source (not shown). The airflow generator 140 can receive pressurized air from the pressurized air source and can pulse the pressurized air into or through the component 200 at a predetermined frequency and amount.

[0060] like Figure 1 As further depicted in , the imaging system 150 of the system 100 has one or more imaging devices or sensors. For this embodiment, the one or more imaging devices include an imaging camera 152. In this example embodiment, the imaging camera 152 is an infrared (IR) camera. The imaging camera 152 is operably configured to capture multiple images (i.e., a collection of still images or videos) of the component 200 when the heating coil 114 heats the component 200 along the traverse direction T1 and traverses relative to the component 200, and in some cases, when the airflow generator 140 pulses air through the internal passage 218 of the component 200. In this way, the imaging camera 152 can detect the transient thermal response of the component 200. That is, the imaging camera 152 is configured to capture multiple images or videos of multiple frames with the transient temperature distribution of the component 200 when the heating coil 114 traverses and inductively heats the component 200 relative to the component 200.

[0061] In some embodiments, the imaging camera 152 may be a medium wavelength IR camera. The medium wavelength IR camera may capture wavelengths in the range of about three to six microns (3-6 μm). It is noteworthy that using the medium wavelength IR camera, the barrier coating 214 is transparent or substantially transparent. Therefore, the medium wavelength IR camera may be used to capture defects in the metal structure 210 and / or the metal bond coating 212. In other embodiments, the imaging camera 152 may be a long wavelength IR camera. The long wavelength IR camera may capture wavelengths in the range of about six to fourteen microns (6-14 μm). Using the long wavelength IR camera, the barrier coating 214 is opaque or substantially opaque. Therefore, the long wavelength IR camera may be used to capture defects in the metal bond coating 212 and the barrier coating 214. In addition, in some embodiments, the imaging system 150 includes a medium wavelength IR camera and a long wavelength IR camera. In this way, the medium wavelength IR camera may capture defects in the metal structure 210 and / or the metal bond coating 212, while the long wavelength IR camera may capture defects in the metal bond coating 212 and the barrier coating 214 of the component 200. This may help determine which structure or coating initiated the defect, whether the defect propagated through the metal structure 210 or only through the coatings 212 , 214 , and may generally provide information useful in making a lifetime estimate for the component 200 .

[0062] Additionally, in some example embodiments, the imaging camera 152 has a thermal sensitivity between 18-50 mK. This range allows for the detection of smaller temperature differences or less steep gradients, thereby allowing for the detection of smaller defects. Additionally, in some example embodiments, the imaging camera 152 has a frame rate of at least 60 Hz. In some embodiments, the imaging camera 152 has a frame rate between 60-500 Hz. In some embodiments, the imaging camera 152 has a frame rate between 250-500 Hz. Such frame rates may allow for the detection of smaller defects (e.g., defects less than 10 mils) because thermal gradient changes near small defects tend to disappear more quickly. In some embodiments, the imaging camera 152 may detect defects or features as small as 80 microns (or approximately 0.003 inches).

[0063] The computing system 160 of the system 100 may include, for example, one or more processors and one or more memory devices embodied in one or more control or computing devices (see Fig.12). The one or more processors may include or may be any suitable processing device, such as a microprocessor, a microcontroller, an integrated circuit, a logic device, and / or other suitable processing device. The one or more memory devices may include one or more computer executable or computer readable media, including but not limited to non-transitory computer readable media, RAM, ROM, hard disk drives, flash drives, and / or other memory devices. The one or more memory devices may store information accessible by the one or more processors, including computer readable instructions executable by the one or more processors. The instructions may be any set of instructions that, when executed by the one or more processors, cause the one or more processors to perform operations, such as any operations and functions for which the one or more processors are constructed, such as activating and controlling various aspects of the system 100. The instructions may be software written in any suitable programming language or may be implemented in hardware. Additionally or alternatively, the instructions may be executed in logically and / or virtually separate threads on one or more processors.

[0064] The memory device can store data that can be accessed by one or more processors. For example, the data can include settings for thermal analysis components, thermal characteristics, etc. The data can also include other data sets, parameters, outputs, information, etc. shown and / or described herein. One or more processors can communicate with a communication interface for communicating with other components of the system 100, for example. The communication interface can include any suitable components for interfacing with one or more networks or electronic components, including, for example, transmitters, receivers, ports, controllers, antennas, and / or other suitable components. The communication interface can be used to communicate with other electronic devices through one or more networks (e.g., local area networks (LANs), wide area networks (WANs), VHF networks, HF networks, Wi-Fi networks, WiMAX networks, gatelink networks, and / or any other suitable communication networks). The communication interface can communicate through one or more networks using a variety of communication protocols. The communication interface can include a combination of a data bus or a wired and / or wireless communication link that connects one or more processors to other electronic devices.

[0065] In particular, one or more processors of computing system 160 may be communicatively coupled to various systems / devices of system 100. For example, one or more processors may be communicatively coupled to heating system 110, platform system 130, airflow generator 140, imaging system 150, among other possible systems or devices thereof. The one or more processors may be communicatively coupled to these various systems and / or devices thereof via one or more wired and / or wireless communication links.

[0066] The system 100 may also include a user interface 170. The user interface 170 is provided for user control of the system 100. For example, the user interface 170 includes a plurality of user controls (not labeled). The user controls may include one or more of a variety of electrical, mechanical, or electromechanical input devices, including rotary dials, buttons, and touch pads and / or screens. The user interface 170 may include one or more display devices 172, such as digital or analog display devices designed to provide feedback or results of the inspection process to the user.

[0067] Figure 3 A flowchart of an example method (300) is provided, wherein Figure 1 The system 100 can perform a coating inspection process on a component, for example, to detect defects in its barrier coating. That is, after coating a component with a barrier coating, the system 100 can be used to inspect the component with a barrier coating. Figure 3 For purposes of illustration and discussion, Figure 3 The actions are depicted as being performed in a particular order. One of ordinary skill in the art using the disclosure provided herein will appreciate that the various actions of any method disclosed herein may be modified in various ways without departing from the scope of the present disclosure. Reference will be made to various features of the system 100 and component 200, and thus, reference will be made generally to Figure 1 , 2 and 3 and other specially noted Figs.

[0068] At (302), the method (300) includes positioning a component having a barrier coating relative to a heating element. For example, a component 200 having a barrier coating 214 can be positioned relative to a heating element 112 of a heating system 110. In some embodiments, the component 200 can be manually loaded into a component holder 134 of a platform system 130. In other embodiments, a robotic arm or other automated device can load the component 200 into the component holder 134. Once the component 200 is secured in the component holder 134, the turntable 136 can rotate the component 200 about its rotational axis to orient the component 200 relative to an imaging camera 152 of an imaging system 150. For example, it may be desirable to orient a particular side (e.g., a pressure or suction side of a turbine blade) or edge (e.g., a leading edge or trailing edge of a turbine blade) of the component 200 relative to the imaging camera 152.

[0069] At (304), the method (300) includes traversing the heating element relative to the component having the barrier coating. For example, the one or more processors of the computing system 160 may cause the heating element 112 to traverse relative to the component 200 along the traversing direction T1. For example, upon receiving an input (e.g., a user input or an input from a sensing device indicating that the component 200 is in a position for inspection and that inspection of the component 200 is to begin), the one or more processors of the computing system 160 may cause the servo motor 122 to move the heating element 112 along the traversing direction T1, where the traversing direction T1 is a direction along the component 200. Figure 1 1. The heating element 112 is traversed relative to the component 200 while the component 200 is held in place by the platform system 130. The heating element 112 may traverse relative to the component 200 at any suitable speed, depending on the thermal output of the heating element 112 and the ability of the imaging system 150 to capture the thermal response of the component 200. As an example, the traversal speed of the heating element 112 relative to the component 200 may be set so that the heating element 112 traverses the entire vertical length of the component 200 in thirty seconds (30s). As another example, the speed at which the heating element 112 traverses or moves relative to the component 200 to detect defects is between 2-5 cm / s.

[0070] At (306), the method (300) includes heating the component with the heating coil while the heating coil traverses relative to the component. For example, when the heating element 112 traverses relative to the component 200 along the traversing direction T1, one or more processors of the computing system 160 may cause the power supply 120 to supply current to the heating element 112. When the heating element 112 is excited by the current provided by the power supply 120, heat radiates from the heating element 112. The heat radiated from the heating element 112 inductively heats the component 200. As a result of being heated by the heating element 112, the component 200 exhibits a transient thermal response. In particular, as Figure 2 As shown, heat radiates outward toward the outer surface 216 of the barrier coating 214 and to the external environment. Transient thermal gradients are generated due to the difference in heat radiated outward from non-defective areas 232 of the barrier coating 214 and heat radiated outward from defects 230 in the barrier coating 214. The imaging camera 152 can capture these transient thermal gradients or responses and detect defects in the barrier coating 214 based on such transient thermal responses.

[0071] At (308), method (300) optionally includes pulsing airflow through an internal passage defined by the component as the heating element traverses relative to the component and applies heat thereto. Figure 1 and 2As shown, in some embodiments, the system 100 includes an airflow generator 140. The component 200 can be positioned on the platform system 130 so that the airflow generator 140 is in fluid communication with the internal channel 218 of the component 200, for example, by one or more pipes fluidly connecting the airflow generator 140 and the one or more internal channels 218 of the component 200. In such an embodiment, the one or more processors of the computing system 160 are configured to cause the airflow generator 140 to pulse an airflow through the one or more internal channels 218 of the component 200 when the heating element 112 traverses relative to the component 200 and applies heat thereto. The pulsed airflow can flow out of one or more holes 220 that are in fluid communication with the one or more internal channels 218. In this way, improved detectability of defects (such as pits and splashes) can be achieved, especially around functionally important features. As previously described, the airflow generator 140 can be controlled to pulse a certain amount of air at a predetermined frequency or interval and provide a predetermined amount of air with each pulse. For example, the predetermined frequency can range from 10 -2 to 10 2 Hz.

[0072] At (310), the method (300) includes capturing multiple images of the component with an imaging device as the heating element traverses relative to the component and applies heat thereto, wherein the multiple captured images may indicate a thermal response of the component to the applied heat. Thus, (304), (306), and (310) may occur simultaneously. In some embodiments, multiple images may be captured as the heating element traverses relative to the component and applies heat thereto while the airflow generator pulses an amount of air into an internal passage of the component. Thus, in some embodiments, (304), (306), (308), and (310) may occur simultaneously. As the heating element 112 traverses relative to the component 200 and applies heat thereto, the imaging camera 152 of the imaging system 150 may be used to capture multiple images of the component 200. The imaging camera 152 may remain in a fixed position as it captures the multiple images.

[0073] In some embodiments, the imaging camera 152 of the imaging system 150 may be a mid-wavelength IR camera operable to capture wavelengths in the range of approximately three to six micrometers (3-6 μm). The mid-wavelength IR camera is particularly suitable for capturing the metal structure 210 ( Figure 2 ) and / or metal bond coating 212 ( Figure 2 ) in the component 200. In other embodiments, the imaging camera 152 may be a long wavelength IR camera operable to capture wavelengths in the range of approximately six to fourteen micrometers (6-14 μm). The long wavelength IR camera is particularly useful for capturing defects in the metal bond coating 212 ( Figure 2 ) and barrier coating 214 ( Figure 2) in the defects.

[0074] Figure 4-7 A schematic diagram of the traversal of the heating element 112 relative to the component 200 is provided as the heating element 112 applies heat thereto (ie, to the component 200). Figure 4 In the example, the heating element 112 is located in a first position, which in this example is a position vertically above the component 200 along the vertical direction V. In this example embodiment, the first position is a starting position. In order to use the imaging camera 152 ( Figure 1 ) captures an image of a transient thermal signature or response of component 200, computing system 160 of system 100 ( Figure 1 ) causes the heating element 112 to traverse relative to the component 200 and apply heat thereto. More specifically, the computing system 160 ( Figure 1 ) causes the heating element 112 to heat the component 200. Heat H is shown as radiating from the heating element 112. The heat H radiated from the heating element 112 imparts thermal energy or heat H to the component 200. Using the heat H radiated from the heating element 112, the computing system 160 ( Figure 1 ) causes one or more processors of the device to traverse the heating element 112 relative to the component 200 along a traverse direction T1, which in this example is downward along the vertical direction V.

[0075] Figure 5 , 6 7 and 8 depict the heating element 112 at various locations along its traversal path. Figure 5 In the embodiment, the heating element 112 is located at the second position, that is, a position below the first position along the vertical direction V. Figure 6 , the heating element 112 is shown in a third position, ie, a position below the second position along the vertical direction V. Figure 7 , the heating element 112 is shown in a fourth position, i.e., a position below the third position along the vertical direction V. In the fourth position, the heating element 112 has completed traversing relative to the component 200 along the traversing direction T1. In this example embodiment, the fourth position is a starting position. The heating element 112 can move or traverse relative to the component 200 along the traversing direction T1 at a constant or substantially constant speed. When the heating element 112 moves along the traversing direction T1 (e.g., from the first position ( Figure 4 ) moves to the fourth position ( Figure 7 )), the imaging camera 152 ( Figure 1 ) may capture multiple images of component 200. Images of component 200 may be captured at any suitable capture rate (eg, any suitable number of frames per second).

[0076] When the heating element 112 traverses relative to the component 200 (e.g., Figure 4 The location shown to Figure 7 When heat H is applied thereto, the imaging camera 152 ( Figure 1 ) captures the transient thermal response of the component 200. More specifically, due to the movement of the heating element 112 relative to the component 200 and the application of heat H to the component 200, the non-defective region 232 ( Figure 2 ) and Defect 230( Figure 2 ) between the imaging camera 152 ( Figure 1 ) is more obvious).

[0077] In particular, if Figure 8 Best shown in Figure 8 A close-up view of the heating element 112 traversing and heating the component 200 is depicted, creating a transient thermal gradient adjacent to and in front of the heating element 112 along the traverse direction Tl, which in this example is below the heating element 112 along the vertical direction V. It is noteworthy that when heat H is applied to the component 200, the non-defective region 232 and the defective region 230 of the component 200 produce different thermal signatures. That is, the non-defective region 232 and the defective region 230 produce different thermal emissivities. In addition, each type of defect can have an identifiable thermal signature or emissivity. For example, the non-defective region 232 of the component 200 can produce a thermal signature such as Figure 8 The first thermal emissivity or first thermal characteristic represented by the cross-hatching pattern in FIG. The pit 230A or void defect may produce a first thermal emissivity or first thermal characteristic represented by the cross-hatching pattern in FIG. Figure 8 In addition, the splash 230B may produce a second thermal emissivity or a second thermal signature represented by the vertical line pattern in FIG. Figure 8 200 . The third thermal emissivity or third thermal signature represented by the horizontal line pattern in . Other types of defects may also have associated thermal emissivities or thermal emistivities. Imaging camera 152 may capture these different transient thermal responses, and computing system 160 may analyze the coating of component 200 based on these different thermal responses captured in the images.

[0078] At (312), in some embodiments, method (300) includes generating a single image from the plurality of captured images, wherein the single image indicates one or more detected coating defects in the barrier coating of the component. For example, one or more processors of computing system 160 may generate a single image from the plurality of captured images captured by imaging camera 152, the single image indicating one or more detected coating defects in the barrier coating of the component. In some embodiments, as Fig.12As shown, one or more memory devices 166 of computing system 160 may store instructions 166A. Instructions 166A may include a single image generator component 165. When single image generator component 165 is executed by one or more processors 164, the captured image is used to generate a single image that generally indicates a defect in the barrier coating of a component or a defect in the component.

[0079] Fig. 9 A schematic diagram of a single image 250 generated from multiple captured images is provided. Fig. 9 A single image 250 may be used as one or more processors 164 ( Fig.12 ) executes instruction 166A( Fig.12 ) of a single image generator component 165 ( Fig.12 ) is generated as a result of Fig. 9 As shown, a single image 250 indicates a coating defect 230 detected in a barrier coating 214 of a component 200. In particular, the single image 250 indicates that the component 200 has one or more pits 230A and one or more splatters 230B. The component and its thermal response to being heated by the heating element 112 when traversed relative to the heating element 112 are embodied in the single image 250 through a plurality of pixels. As will be explained in greater detail herein, each pixel in the single image 250 representing a portion of the component 200 may indicate a maximum temperature captured by the imaging camera 152 for that particular pixel. That is, each pixel of the single image 250 represents the maximum sensed temperature of that pixel, given that all temperature data is received for all captured images.

[0080] Notably, the single image 250 is generated from captured images that all depict the component 200 in the same orientation or position relative to the imaging camera 152. That is, the single image 250 is generated from images that all capture the same perspective of the component 200. For example, where the component is a high pressure turbine blade of a gas turbine engine, a first single image may be generated for a first side of the blade (e.g., the pressure side of the blade) based on multiple images capturing the first side, and a second single image may be generated for a second side of the blade (e.g., the suction side of the blade) based on multiple images capturing the second side. It should be understood that other single images may also be generated for other sides or perspectives of the component 200.

[0081] Example ways in which multiple captured images may be used by one or more processors of computing system 160 to generate a single image will be referenced herein. Figure 13-22 and accompanying text for a detailed description.

[0082] At (314), the method (300) includes detecting one or more coating defects in a barrier coating of the component based at least in part on a thermal response of the component captured in the plurality of images. For example, in some embodiments, the computing system 160 ( Figure 1 ) detects one or more coating defects in a barrier coating of a component using a single image generated at (312), the single image being generated using a plurality of captured images. In some embodiments, computing system 160 includes a computer vision system. Thus, as Fig.12 As shown, instructions 166A stored on one or more memory devices 166 may include a vision system component 167. The vision system component 167 may include signal processing features as well as machine learning algorithms. For example, the machine learning algorithm may be embodied in a convolutional neural network. In general, when the vision system component 167 is executed by one or more processors 164, one or more defects are typically detected in a barrier coating of a component or a component, and the detected defects may be analyzed so that various characteristics of the detected defects may be determined. The vision system component 167 may include a defect detector component 167A. When the defect detector component 167A is executed by one or more processors 164, one or more defects are typically detected in a barrier coating of a component or a component.

[0083] In some embodiments, when detecting one or more coating defects in a barrier coating of a component based at least in part on a thermal response of the component captured in the image at (314), one or more processors of the computing system 160 are configured to identify one or more regions of the barrier coating having a transient thermal response outside of a predetermined range. In such embodiments, the one or more regions of the barrier coating having a transient thermal response outside of the predetermined range are identified as one or more coating defects of the barrier coating.

[0084] In some exemplary embodiments, the transient thermal response of a component may be defined in terms of a transient thermal gradient (e.g., the ratio of the temperature difference to the distance between two points, or equivalently, the temperature change over a given length). Fig.10A close-up view of a single image 250 is provided. The single image 250 includes a plurality of pixels P. A small sample size of pixels is specifically labeled, including a first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, and sixteenth pixel, labeled P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, P11, P12, P13, P14, P15, and P16, respectively. In this example, the pixels P are square, but in other embodiments, the pixels P can be other suitable shapes. In this example, in order to identify one or more regions of the barrier coating having a transient thermal response outside of a predetermined range, one or more processors of the computing system 160 are configured to determine a plurality of transient thermal gradients.

[0085] like Fig.10 As shown, the predetermined length or distance between two points can be the distance between the center of a pixel and the center of an adjacent pixel. Other predetermined lengths associated with determining the thermal gradient are possible. For example, the predetermined length or distance between two points can be the distance between the center of a pixel and the center of a pixel five pixels apart. It should be understood that these are exemplary predetermined lengths. In this example embodiment, for each pixel P, a transient thermal gradient is determined for each adjacent pixel. For example, a first transient thermal gradient G1 is determined between the first pixel P1 and the second pixel P2, and a second transient thermal gradient G2 is determined between the first pixel P1 and the fifth pixel P5. It should be understood that the predetermined length or distance between two points can be the distance between the center of a pixel and the center of a pixel five pixels apart. Fig.10 The pixels above and to the left of the first pixel P1 in the image are used to determine the transient thermal gradients. The small sample size of the determined thermal gradients is specifically labeled, including the first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, sixteenth, seventeenth, eighteenth, nineteenth, twentieth, twenty-first, twenty-second, twenty-third and twenty-fourth transient thermal gradients, labeled G1, G2, G3, G4, G5, G6, G7, G8, G9, G10, G11, G12, G13, G14, G15, G16, G17, G18, G19, G20, G21, G22, G23 and G24, respectively.

[0086] Using the determined thermal gradients, one or more processors of computing system 160 are configured to determine whether one or more of the determined transient thermal gradients are outside of a predetermined range, for example, outside of a range of values ​​associated with transient thermal gradients expected to be associated with non-defective regions of a component. Each transient thermal gradient may be compared to a predetermined range. For example, Fig.10, it is determined whether each transient thermal gradient G1, G2, G3, G4, G5, G6, G7, G8, G9, G10, G11, G12, G13, G14, G15, G16, G17, G18, G19, G20, G21, G22, G23, and G24 (and so on for thermal gradients not shown) falls within a predetermined range. In this example, one or more processors of computing system 160 determine that G4, G6, G9, G12, G16, G18, G19, and G20 are outside the predetermined range and the remaining transient thermal gradients are not outside the predetermined range. Therefore, one or more processors of computing system 160 can determine or identify pixels P6, P7, P10, and P11 as areas of the barrier coating of the component that are defects in the barrier coating of the component. Other areas can be identified as defects in the same manner as described above.

[0087] In some embodiments, the predetermined range is one of a plurality of predetermined ranges. Each predetermined range can be associated with an area or location of the component. For example, one predetermined range can be associated with the leading edge of the component, one predetermined range can be associated with the area around the cooling hole, one predetermined range can be associated with the trailing edge of the component, etc. In such embodiments, the determined thermal gradient can be compared with a predetermined range in the plurality of predetermined ranges, the predetermined range being associated with an area or location corresponding to the location of the pixel under consideration.

[0088] In some other example embodiments, the transient thermal response of a component may be defined in terms of transient thermal emissivity. As an example, Fig.11 Another close-up view of a portion of a single image 250 is provided. Fig.10 A single image of 250, Fig.11 The single image 250 of includes a plurality of pixels P, including a first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, and sixteenth pixel, labeled P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, P11, P12, P13, P14, P15, and P16, respectively. In this example, the pixels P are square, but in other embodiments, the pixels P may be other suitable shapes. In this example, in order to identify one or more areas of the barrier coating having a transient thermal response outside of a predetermined range, one or more processors of the computing system 160 are configured to determine the thermal emissivity of the component embodying each pixel P. As described above, each pixel P may indicate a maximum temperature captured for the particular pixel, given all temperatures captured in the plurality of images for the particular pixel.

[0089] like Fig.11As shown, a transient thermal emissivity is determined for each pixel P. For example, a first emissivity R1 is determined for the first pixel P1, a second emissivity R2 is determined for the second pixel P2, and so on, a transient thermal emissivity is determined for each pixel P. In this way, the first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth and sixteenth thermal emissivities can be determined for their associated pixels, as shown in FIG. Fig.11 The thermal emissivities are marked as R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15 and R16 respectively.

[0090] Using the determined thermal emissivities, one or more processors of computing system 160 are configured to determine whether one or more of the determined thermal emissivities are outside of a predetermined range, for example, outside of a range of values ​​associated with transient thermal emissions expected to be associated with non-defective regions of the component. Each transient thermal emissivity may be compared to the predetermined range. For example, Fig.11 , it is determined whether one or more of the transient thermal emissivities R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, and R16 (and so on for thermal emissivities not shown) fall within a predetermined range. In this example, one or more processors of computing system 160 determine that thermal emissivities R6, R7, and R11 are outside the predetermined range and the remaining transient thermal emissivities are not outside the predetermined range. Therefore, one or more processors of computing system 160 can determine or identify pixels P6, P7, and P11 as areas of the barrier coating of the component that are defects in the barrier coating of the component. Other areas can be identified as defects in the same manner as described above.

[0091] In some embodiments, the predetermined range is one of a plurality of predetermined ranges. Each predetermined range can be associated with an area or location of the component. For example, one predetermined range can be associated with the leading edge of the component, one predetermined range can be associated with the area around the cooling hole, one predetermined range can be associated with the trailing edge of the component, etc. In such embodiments, the determined thermal emissivity can be compared with a predetermined range of the plurality of predetermined ranges that is associated with an area or location corresponding to the location of the pixel under consideration.

[0092] In some embodiments, when detecting one or more coating defects in a barrier coating of a component based at least in part on a thermal response of the component captured in an image at (314), one or more processors of the computing system 160 are configured to determine a rate of temperature change associated with a pixel or group of pixels of the captured image. Notably, defects may be detected both during heating and cooling of the component. Thus, a heating rate associated with a pixel may be determined and / or a cooling rate associated with a pixel may be determined. The determined heating rate of the pixel or group of pixels may be compared to a predetermined heating rate. The predetermined heating rate may be a heating rate associated with an expected heating rate of a non-defective region of the component. Thus, if the determined heating rate of the pixel or group of pixels is outside the predetermined heating rate, the pixel or group of pixels outside the predetermined heating rate may be determined or identified as a defect in the barrier coating (or a portion of a defect in the barrier coating). Additionally, for a pixel or group of pixels having a heating rate determined to be outside the predetermined heating rate, the determined heating rate of the pixel or group of pixels may be used to classify the defect associated therewith. For example, various defects (e.g., splatters, pits, delamination, etc.) may have corresponding expected heating rate ranges. The one or more processors may determine within which heating rate range the determined heating range falls, and may classify the type of defect accordingly.

[0093] Additionally or alternatively, the cooling rate of the determined pixel or pixel group can be compared to a predetermined cooling rate. The predetermined cooling rate can be a cooling rate associated with an expected cooling rate for a non-defective area of ​​the component. Therefore, if the cooling rate of the determined pixel or pixel group is outside the predetermined cooling rate, the pixel or pixel group outside the predetermined cooling rate can be determined or identified as a defect in the barrier coating (or part of a defect in the barrier coating). In addition, for pixels or pixel groups having a cooling rate determined to be outside the predetermined cooling rate, the cooling rate of the determined pixel or pixel group can be used to classify the defects associated therewith. For example, various defects (such as splatters, pits, delamination, etc.) may have corresponding expected cooling rate ranges. One or more processors can determine in which cooling rate range the determined cooling range falls, and can classify the type of defect accordingly.

[0094] Fig.12A graph depicting a time-temperature curve of a pixel according to one embodiment of the present disclosure is provided. As shown, when heat is applied to the component via a traversing heating element, the portion of the component associated with the pixel begins to rise at t=0 seconds. At approximately t=5 seconds, the pixel reaches a peak amplitude or peak temperature. After reaching the peak amplitude, when the heating element moves away from the position of the component associated with the pixel, the position of the component corresponding to the pixel begins to cool. One or more processors can generate a time-temperature graph for each pixel or group of pixels of a captured image.

[0095] As described above, one or more processors may determine a heating rate associated with a pixel. The heating rate may be determined based on the instantaneous temperature of the pixel captured in a plurality of images and the frame rate of the imaging device. The heating rate of the pixel depends on the material properties of the component and whether there is a defect at the location of the component associated with the pixel. In some embodiments, the heating rate may be determined as an average heating rate over a predetermined time period. As an example, the predetermined time period may be from the time the pixel exceeds a temperature threshold relative to its ambient temperature to the time the pixel reaches a peak amplitude (e.g., at Fig.12 The predetermined time period may be a time period from time t=0 seconds to time t=5 seconds in the predetermined heating rate range). As another example, the predetermined time period may be a predefined time period in which the temperature of a portion of a component associated with the pixel rises. The heating rate may be determined and compared to a predetermined heating rate range as described above. When the pixel has a determined heating rate within the predetermined heating rate range, the position of the component associated with the pixel is identified as a non-defective portion or region of the component. When the pixel has a determined heating rate outside the predetermined heating rate range, the position of the component associated with the pixel is identified as a defect or defective region of the component. In addition, when the pixel has a determined heating rate outside the predetermined heating rate range, the defect type may be classified based on the determined heating rate, for example, in the manner described above.

[0096] Additionally or alternatively, one or more processors may determine a cooling rate of a portion of a component associated with a pixel. The cooling rate may be determined based on the instantaneous temperature of the pixel captured in a plurality of images and a frame rate of the imaging device. The cooling rate of a pixel depends on the material properties of the component and whether there is a defect at the location of the component associated with the pixel. In some embodiments, the cooling rate may be determined as an average cooling rate over a predetermined time period. As an example, the predetermined time period may be the time from when the pixel reaches a peak amplitude to when the pixel reaches a temperature outside a predefined margin of the peak amplitude (e.g., within a predetermined time period). Fig.12As another example, the predetermined time period may be some other predefined time period. The cooling rate may be determined and compared to a predetermined cooling rate range as described above. When a pixel has a determined cooling rate within the predetermined cooling rate range, the position of a component associated with the pixel is identified as a non-defective portion or region of the component. When a pixel has a determined cooling rate outside the predetermined cooling rate range, the position of a component associated with the pixel is identified as a defect or defective region of the component. In addition, when a pixel has a determined cooling rate outside the predetermined cooling rate range, the defect type may be classified based on the determined cooling rate, for example, in the manner described above.

[0097] Notably, the peak amplitude associated with a pixel may correspond to or be a measure of the size of a defect. The larger the amplitude of the pixel, the larger the defect, and conversely, the smaller the amplitude of the pixel, the smaller the defect. Thus, in some embodiments, the size of the defect may be determined based at least in part on the amplitude of the pixel on its determined time-temperature curve. Furthermore, in some embodiments, if the peak amplitude associated with a pixel is below an amplitude threshold (i.e., below a temperature threshold), the heating and / or cooling rate of the pixel is not determined because the pixel is not or is not likely to be associated with a defect. This may save valuable computational resources of one or more processors.

[0098] At (316), the method (300) includes analyzing the detected coating defects in the component. For example, one or more processors of the computing system 160 may use the single image generated at (312) to analyze the detected defects in the component. In some embodiments, Fig.12 As shown, the vision system component 167 includes a defect analyzer component 167B. When the defect analyzer component 167B is executed by one or more processors 164, the defect detected at (314) can be analyzed so that various characteristics of the detected defect can be determined. In some embodiments, the defect detector component 167A and the defect analyzer component 167B can be combined into a single component or instruction set.

[0099] In some embodiments, when analyzing the detected defects in the component at (316), one or more processors of the computing system 160 are configured to determine one or more characteristics associated with the detected defect or defect area identified at (314). For example, one or more processors of the computing system 160 may be configured to determine the number of one or more coating defects in the identified barrier coating. That is, a total number of defects identified in the coating or component may be determined. The number of defects identified may represent the total number of defects identified in a single image. Since a single image may only capture one side or perspective of a component, it will be appreciated that the number of defects in other single images generated for other perspectives or sides of the component may need to be added together to determine the total number of defects in the barrier coating of the component. For example, in the case where the component is a high pressure turbine blade of a gas turbine engine, the number of defects identified in a first single image generated for a first side of the blade (e.g., the pressure side of the blade) will need to be added to the number of defects identified in a second single image generated for a second side of the blade (e.g., the suction side of the blade) to determine the total number of defects in the component.

[0100] The one or more processors of computing system 160 may be configured to also determine other characteristics associated with the detected defects. For example, the one or more processors of computing system 160 may be configured to determine the depth or height of the identified coating defect. Figure 2 , determining the depth D1 of a defect (e.g., pit 230A) can provide information about the severity of the defect. In particular, determining the depth D1 of the defect can provide information about whether the metal structure 210 or the bond coating 212 of the component 200 is exposed to the external environment due to the defect or whether the defect is contained in the barrier coating 214. In addition, the depth of the defect can provide information about errors or problems with the coating machine or process. In some embodiments, the depth D1 can be defined as the distance from the outer surface 216 of the barrier coating 214 to the deepest part of the defect, such as Figure 2 In other embodiments, the depth D1 can be defined as the distance from the outer surface 216 of the barrier coating 214 to the average depth of the defects.

[0101] It may also be useful to determine the height E1 of a defect, such as splatter 230B. For example, the height E1 of a defect may provide information about errors or problems with a coating machine or process, and may provide insight into the likelihood that the splatter will break off and the size of the void that would result if the splatter were to break off from a component, such as during engine operation. In some embodiments, the height E1 may be defined as the distance from the outer surface 216 of the barrier coating 214 to the apex of the defect, such as Figure 2In other embodiments, height E1 may be defined as the distance from outer surface 216 of barrier coating 214 to the average height of the defects.

[0102] The depth and / or height of a defect may be determined by one or more processors of computing system 160 based on the thermal response of the component captured in a single image. For example, a defect having a greater depth may exhibit a higher thermal emissivity than a defect having a shallower depth. Thus, the emissivity represented by the pixels of a single image may be related to the depth (e.g., via a lookup table). Additionally, a defect having a greater height may exhibit a lower thermal emissivity than a defect having a lower height. Thus, the emissivity represented by the pixels of a single image may be related to the height (e.g., via a lookup table).

[0103] The one or more processors of the computing system 160 may also be configured to determine an area fraction or percentage of each of the coating defects of the identified barrier coating. That is, the fraction of the area of ​​a given defect or defect region relative to the total surface area of ​​the component (or the total surface area of ​​the side of the component depicted in a single image) may be determined. As an example, the number of pixels associated with the defect may be compared to the total number of pixels in a single image representing a portion of the component. The area fraction of the defect may also be determined in other suitable ways. In addition, the one or more processors may be configured to determine the total area fraction of the portion of the component represented in the single image, for example, by adding together all area fractions associated with the identified defects and comparing the sum relative to the total surface area of ​​the portion of the component represented in the single image. In addition, in some embodiments, the one or more processors may be configured to determine the total area fraction of the component, for example, by adding together all area fractions associated with the identified defects and comparing the sum relative to the total surface area of ​​the portion of the component. In order to determine the total area fraction of the component associated with the identified defect, it should be understood that the area fractions determined for defects of other generated single images (e.g., single images representing the other side of the component) will be considered when determining the total area fraction.

[0104] In some embodiments, when analyzing the detected defects in the component at (316), one or more processors of the computing system 160 are configured to classify the defects into a class or type of defect, such as a pit or a spatter. In some embodiments, the one or more processors of the computing system 160 are configured to classify the identified defects based at least in part on the thermal response of the identified defects. For example, as described above, non-defective areas of the component and defects produce different thermal emissivities, and the pixels of the component represent this fact. In addition, certain defects produce thermal emissivities within a recognizable range. For example, pits may produce thermal emissivities within a first predetermined range, spatters may produce thermal emissivities within a second predetermined range, and so on for other types of defects. Therefore, the thermal emissivity of each defect can be used to classify the type of the identified defect. Each defect can be classified based on an average thermal emissivity represented by the pixels associated with a given defect and / or based on pixels associated with defects having the largest or lowest thermal emissivity.

[0105] In addition, the thermal gradients determined between adjacent pixels may also be used to classify defects. For example, a pit may produce a gradient having a steepness or slope within a first predetermined range, a splatter may produce a gradient having a steepness or slope within a second predetermined range, and so on for other types of defects. In some embodiments, the average slope or steepness of all thermal gradients extending from pixels representing non-defective areas and pixels forming part of the perimeter of the identified defect (e.g., Fig.10 In other embodiments, each defect may be classified based on the steepest and / or lowest slope, taking into account all thermal gradients extending from pixels representing non-defective areas and pixels forming part of the perimeter of the identified defect.

[0106] In some other embodiments, when analyzing the defects in the detected component at (316), one or more processors of the computing system 160 are configured to classify the defects into a class or type of defect based at least in part on one or more determined characteristics associated with the defect. For example, the depth and / or height of a particular defect may be used to classify the defect. For example, a defect having a depth within a predetermined depth range may be classified as a pit, a defect having a height within a predetermined height range may be classified as a spatter, and so on for other types of defects. In some embodiments, when analyzing the defects in the detected component at (316), one or more processors of the computing system 160 are configured to classify the defect into a class or type of defect based at least in part on one or more determined characteristics associated with the defect and a thermal response of the identified defect.

[0107] At (318), the method (300) includes determining whether the barrier coating of the component is an acceptable barrier coating. For example, in one aspect, when the barrier coating of the component passes all or some combination of predefined criteria, the barrier coating is determined to be acceptable. In another aspect, when the barrier coating of the component does not pass all or some combination of predefined criteria, the barrier coating is determined to be unacceptable.

[0108] In some embodiments, the one or more processors of the computing system 160 are configured to determine whether the barrier coating of the component is an acceptable barrier coating based on at least one of the following comparisons: a comparison of the number of one or more coating defects of the identified barrier coating to a number threshold; a comparison of the depth of each of the one or more coating defects of the identified barrier coating to a depth threshold; a comparison of the area fraction of the one or more coating defects of the identified barrier coating to an area fraction. In some embodiments, the barrier coating must pass all of the comparisons. In other embodiments, the barrier coating must pass some combination thereof, such as two of the three comparisons.

[0109] In addition to or in lieu of the comparisons mentioned above, in some embodiments, the one or more processors of the computing system 160 are configured to determine whether the barrier coating of the component is an acceptable barrier coating based on the number of defects classified as a particular type of defect exceeding a number threshold, an area fraction threshold, etc. For example, if the number of pits exceeds a pit number threshold, the barrier coating will be determined to be unacceptable. Other predefined criteria for determining whether the barrier coating is acceptable are also possible. The one or more processors of the computing system 160 can automatically determine whether the barrier coating is acceptable without any manual visual inspection of the component.

[0110] At (320), method (300) includes displaying information associated with the inspection of the component. For example, one or more processors of computing system 160 may cause display device 172 to display information associated with the inspection of the component. Various types of information may be displayed. For example, the results of the inspection process may be displayed on display device 172, for example, a graphic on display device 172 may indicate whether the barrier coating of the component is acceptable or unacceptable. In addition, determined characteristics of the detected defects may be displayed on display device 172. For example, but not limited to, the number or total number of identified defects may be displayed, the total area fraction of the identified defects may be displayed, the depth of various defects may be displayed, and the height of various defects may be displayed. Other characteristics associated with the identified defects may also be displayed.

[0111] In addition, the single image generated at (312) can be displayed on the display device 172. The displayed single image can indicate the thermal response or characteristics of the component 200 in response to the heating element 112 traversing relative to the component 200 and applying heat thereto. When the single image is displayed, characteristics associated with defects identified in the single image can also be displayed. In addition, other single images generated for other views of the component can be displayed on the display device 172. The user interface 170 provides a means for scrolling between the generated single images. When a particular single image is displayed on the display device 172, characteristics associated with defects identified in that particular single image can also be displayed.

[0112] Fig.12 A block diagram of a computing system 160 is provided. Computing system 160 may include one or more computing devices 162 that may be used to implement the methods and systems described herein according to example embodiments of the present disclosure. Computing device 162 is one example of a suitable computing device for implementing the computing elements described herein.

[0113] As previously described, computing device 162 may include one or more processors 164 and one or more memory devices 166. One or more processors 164 may include any suitable processing device, such as a microprocessor, a microcontroller, an integrated circuit, a logic device, or other suitable processing device. One or more memory devices 166 may include one or more computer-readable media, including but not limited to non-transitory computer-readable media, RAM, ROM, hard drives, flash drives, and other memory devices, such as one or more buffer devices.

[0114] The one or more memory devices 166 may store information accessible by the one or more processors 164, including computer-readable instructions 166A executable by the one or more processors 164. The instructions 166A may be any set of instructions that, when executed by the one or more processors 164, cause the one or more processors 164 to perform operations, such as, among other operations, causing a heating element to traverse relative to a component while applying heat thereto, causing an airflow generator to pulse air into an internal passage of a component, causing a single image to be generated from multiple captured images, and / or causing a vision system to detect and analyze identified defects. The instructions 166A may be software written in any suitable programming language or may be implemented in hardware. In some embodiments, the instructions 166A may be executed by the one or more processors 164 to cause the one or more processors 164 to perform operations.

[0115] The memory device 166 may also store data 166B accessible by the processor 164. For example, the data 166B may include images captured by an imaging device, baseline data, model data, logic data, etc., as described herein. According to an example embodiment of the present disclosure, the data 166B may include one or more tables, functions, algorithms, models, equations, etc.

[0116] The computing device(s) 162 may also include a communication interface 168 for communicating, for example, with other components of the system. The communication interface 168 may include any suitable components for interfacing with one or more networks, including, for example, a transmitter, receiver, port, controller, antenna, or other suitable components.

[0117] Generation of a single observation image

[0118] The manner in which a single observation image can be generated by one or more processors using images captured by an imaging device will now be described in detail. Capturing the transient thermal response into a single observation image allows for faster and more accurate inspection of components. The 3D data (multiple captured images or movies) is intelligently processed into a 2D image that indicates the transient thermal response of the component without depicting traversing heating elements.

[0119] Fig.14 A flowchart of an example method (400) for generating a single observation image is provided. For example, the method (400) may be used to generate Fig. 9 A single image of 250. Reference Fig.12 , one or more processors 164 of computing system 160 may execute single image generator component 165 of instructions 166A to generate single image 250. For purposes of illustration and discussion, Fig.14 The actions are depicted to be performed in a specific order. One of ordinary skill in the art using the disclosure provided herein will appreciate that the various actions of any method disclosed herein may be modified in various ways without departing from the scope of the present disclosure. Reference will be made to the various features of the coating inspection system 100 and component 200 described herein and shown in the figures.

[0120] At (402), the method (400) includes receiving, by one or more processors, a plurality of images captured by an imaging device. Each of the plurality of images captures a component having a barrier coating as a heating element traverses relative to the component in a traversing direction and applies heat thereto. For example, one or more processors 164 of the computing system 160 may receive a plurality of images captured by the imaging camera 152. The component may be Figure 1 The component 200 depicted in FIG. 1 or some other component having a metal structure and a barrier coating. The multiple images or frames may collectively depict the thermal response of the component as the heating element traverses relative to the component in a traverse direction and applies heat thereto. That is, Figure 1 The imaging camera 152 may traverse the heating element 112 along its traversal path and apply heat to the component 200 (e.g., as Figure 4-7 The imaging device may capture images of the thermal response of the component 200 as the heating element 112 sweeps across the component 200 and imparts heat to the component 200. That is, each image may capture the instantaneous temperature distribution of the component 200 in response to the heating element 112 sweeping across the component 200 and imparting heat to the component 200. Because cracks and other defects are surface discontinuities, they create obstacles for the flow of eddy currents, and therefore, hot spots form as temporal and spatial events in the temperature distribution in the image captured by the imaging device. Thus, the separate images may each capture the local transient thermal response of the component. Each image may have the same number of pixels.

[0121] At (404), the method (400) includes generating a plurality of masked images using the captured plurality of images. For example, the one or more processors 164 of the computing system 160 may generate the masked images using the captured images received at (402). In some embodiments, the masked images are generated by positioning a masking window adjacent to and in front of the heating element along a transverse direction for each image in the plurality of images and applying thermal data to pixels within the masking window for each image in the plurality of images.

[0122] As an example, Figure 15-18 A plurality of images 260 of a component 200 captured by an imaging device are depicted as the heating element 112 traverses relative to the component 200 and applies heat thereto along a traverse direction T1. In this example, the traverse direction T1 is a direction along the vertical direction V. However, as noted, in other embodiments, the traverse direction T1 may extend along a different direction. Furthermore, it should be understood that the imaging device may capture more than one image. Figure 15-18 Many more images are shown in FIG, including images captured before, between, or after the depicted captured image 260. The captured images 260 or frames may collectively capture the progression of the heating element 112 across the entire length (eg, vertical length) of the component 200.

[0123] like Fig.15 , 16 As shown in each of the images 260 of 17 and 18, one or more processors of the computing system 160 position the masking window 270 adjacent to and in front of the heating element 112 along the transverse direction T1. Thus, as shown, the masking window 270 moves with the heating element 112 from frame to frame or from image to image. The masking window 270 is positioned in the image 260 of FIG. Figure 15-18 It is depicted as a rectangle, but other shapes are possible.

[0124] In system 100( Figure 1) is that as the heating element 112 traverses relative to the part 200, thermal transients or anomalies begin to appear in front of the heating element 112. In particular, the thermal transients appear significantly relative to the background (i.e., non-defective areas) just in front of the heating element 112. Therefore, in some embodiments, the masking window 270 is placed adjacent to and in front of the heating element 112 in each captured image 260. Thus, in this example, in Figure 15-18 In each captured image 260 of FIG. 1 , the masking window 270 is positioned adjacent to and in front of the heating element 112 (just below the heating element 112 along the vertical direction V).

[0125] like Fig.15 As best shown, each masking window 270 has a first length L1 (e.g., a length extending along the transverse direction T1) and a second length L2 (e.g., a length extending perpendicular to the transverse direction T1). For this embodiment, the second length L2 of the masking window 270 spans the width of the captured image 260. Each masking window may have a second length L2 that spans the width of the image on which the masking window is located. In some embodiments, the second length L2 of the masking window 270 spans the width of the component 200. The first length L1 of the masking window 270 may be selected based on the selected heat output and the traversal speed of the heating element 112. In some embodiments, the first length L1 of the masking window 270 is selected so that the masking window 270 captures the thermal response of the component 200 generated by the heat radiated by the heating element 112 within its perimeter, but is otherwise kept as short as possible to minimize computer processing time. In some embodiments, the first length L1 of the masking window 270 is less than one-quarter of the component length LC1 of the component 200. The component length LC1 extends along the transverse direction T1. In some embodiments, the first length L1 of the masking window 270 is less than one eighth of the component length LC1 of the component 200 .

[0126] With the masking window 270 positioned adjacent to and in front of the heating element 112 in each captured image 260, one or more processors 164 of the computing system 160 apply thermal data to pixels within the masking window 270 of each image 260. Notably, the masking window 270 is used to mask pixels outside its perimeter. Thus, for each image 260, pixels outside the masking window 270 are ignored. In some embodiments, the imaging device is an infrared imaging device and the thermal data is three-dimensional (3D) infrared sensor data. The thermal data may indicate an instantaneous temperature distribution of the component 200. In some embodiments, applying the thermal data to pixels within a corresponding masking window positioned in each of the plurality of images includes assigning a value (e.g., a temperature value) to each pixel within the corresponding masking window positioned in the image.

[0127] As an example, Fig.19 A schematic diagram of thermal data of pixels of a masking window applied to each image is provided. As shown, thermal data 280A is applied to a pixel P positioned in a masking window 270A on a first captured image 260A, thermal data 280B is applied to a pixel P positioned in a masking window 270B on a second captured image 260B, thermal data 280C is applied to a pixel P positioned in a masking window 270C on a third captured image 260C, and so on for N captured images, where N is an integer. Each pixel in a specific masking window can receive thermal data (e.g., receive a temperature value). As depicted, thermal data 280A, 280B, 280 and 280N are only applied to pixels P in corresponding masking windows 270A, 270B, 270C and 270N of captured images 260A, 260B, 260C and 260N. Pixels outside the masking window are ignored. Among other benefits, masking pixels outside of the masking window can reduce the processing time and computing resources required to apply thermal data to the 2D captured image.

[0128] Fig. 20 A schematic diagram of multiple generated mask images 290 is provided. Each generated mask image 290 represents the pixels of its associated mask window to which thermal data is applied. For example, the first mask image 290A represents the pixels P of its associated first mask window 270A to which thermal data 280A is applied, the second mask image 290B represents the pixels P of its associated second mask window 270B to which thermal data 280B is applied, the third mask image 290C represents the pixels P of its associated third mask window 270C to which thermal data 280C is applied, and so on, until the Nth mask image.

[0129] As described above, when the heating element traverses relative to the component, it is found that the thermal transient or anomaly begins to appear in front of the heating element. Capturing and considering the pixels in front of the heating element can provide valuable insights into determining the maximum temperature value and / or heating rate associated with the pixel. However, as described above, the minimum temperature value and / or cooling rate associated with the pixel can also be considered. It is understood that after the heating element traverses a specific portion of the component, the component begins to cool. In order to capture the minimum temperature value and / or cooling rate associated with the pixel, in some embodiments, the masking window can be positioned behind the heating element along the traversing direction. It should also be understood that the maximum temperature value can be captured within the masking window positioned behind the heating element. In addition, insights into the heating rate associated with the pixel can also be captured within the masking window positioned behind the heating element.

[0130] As an example, Fig.21 As shown, in each captured image ( Fig.21In the captured image 260 (only one is shown), the masking window 270 is positioned adjacent to and behind the heating element 112 along the transverse direction T1. Fig.21 The masking window 270 is positioned to capture the transient thermal response of the component 200 as the component 200 cools. In some embodiments, the masking window 270 positioned behind the heating element 112 along the transverse direction T1 need not be positioned adjacent to the heating element 112; instead, for example, there may be a space between the heating element 112 and the masking window 270 along the transverse direction T1.

[0131] In other embodiments, the masking window includes two sections, including a front section and a rear section. In such embodiments, the front section of the masking window is positioned adjacent to and in front of the heating element in each captured image along the transverse direction, and the rear section of the masking window is positioned adjacent to and behind the heating element in each captured image along the transverse direction. In such embodiments, the front section and the rear section may be discontinuous sections.

[0132] As another example, Fig. 22 As shown, the masking window 270 includes two sections, including a front section 272 and a rear section 274. In such an embodiment, in each captured image ( Fig. 22 In the captured image 260 (only one captured image 260 is shown), the front section 272 of the masking window 270 is positioned adjacent to and in front of the heating element 112 along the transverse direction T1, and the rear section 274 of the masking window 270 is positioned adjacent to and behind the heating element 112 along the transverse direction T1 in each captured image. The front section and the rear section 272, 274 can be discontinuous sections, such as Fig.21 In addition, in such an embodiment, the rear section 274 may have a length L1-B (eg, a length extending along the transverse direction T1), which is at least twice the length L1-F (eg, a length extending along the transverse direction T1) of the front section 272 of the masking window 270.

[0133] In some embodiments, the front section 272 positioned in front of the heating element 112 along the transverse direction T1 need not be positioned adjacent to the heating element 112; instead, for example, there may be a space between the heating element 112 and the front section 272 along the transverse direction T1. Additionally or alternatively, in some embodiments, the rear section 274 positioned behind the heating element 112 along the transverse direction T1 need not be positioned adjacent to the heating element 112; instead, for example, there may be a space between the heating element 112 and the rear section 274 along the transverse direction T1.

[0134] At (406), method (400) includes determining a minimum value and / or maximum value associated with each pixel on the plurality of masked images based at least in part on the applied thermal data. That is, considering all thermal data values ​​for a particular pixel, a minimum value and / or maximum value is determined for the particular pixel. In some embodiments, the minimum value and / or maximum value is a minimum temperature value and / or a maximum temperature value. In some embodiments, determining the minimum value and / or maximum value associated with each pixel on the plurality of masked images at (406) includes determining, for each pixel in the plurality of masked images, each of the plurality of masked images in which a given pixel in the plurality of masked images is represented, and comparing the values ​​associated with the given pixel from each of the masked images in which the given pixel is represented. To determine the minimum value, the smallest value associated with the given pixel is selected as the minimum value associated with the given pixel. To determine the maximum value, the largest value associated with the given pixel is selected as the maximum value associated with the given pixel.

[0135] As an example, Fig.23 Several mask images 290 are depicted, including a first mask image 290D, a second mask image 290E, a third mask image 290F, and a fourth mask image 290G. Mask images 290D, 290E, 290F, and 290G are created using successive images captured by an imaging device. Each mask image 290 includes a plurality of pixels P. Some or all of the pixels P may be represented in a plurality of mask images 290. For example, as shown, pixel P10 is represented in a plurality of mask images 290.

[0136] In order to determine the maximum value associated with the pixel P10 on the plurality of masked images 290, each masked image in which the pixel P10 appears is determined. In this example, the pixel P10 is found within the periphery of the first masked image 290D, the second masked image 290E, and the third masked image 290F, but not within the periphery of the fourth masked image 290G. Therefore, only the first, second, and third masked images 290D, 290E, and 290F are considered to determine the maximum value of the pixel P10. In the first masked image 290D, the pixel P10 has a value T1 (e.g., a temperature value). In the second masked image 290E, the pixel P10 has a value T2. In the third masked image 290F, the pixel P10 has a value T3. In this example, for the pixel P10, T3>T2>T1. Therefore, for the pixel P10, the maximum value is T3. It should be understood that the maximum value of each pixel on the plurality of masked images 290 can be determined in the same manner as described for the pixel P10. For example, the maximum value of pixel P11 can be determined in the same manner. In this example, for pixel P11, T2>T3>T1. Therefore, for pixel P11, the maximum value is determined to be T2. The minimum value of a pixel can be determined in a similar manner to that described, except that the minimum value is used instead of the maximum value.

[0137] At (408), method (400) includes generating a single observed image of the component using multiple masked images, and causing the determined minimum and / or maximum values ​​associated with each pixel in the multiple masked images to be represented in the single observed image. For example, one or more processors of computing system 160 may generate a single observed image. In some embodiments, one or more processors of computing system 160 may generate a single observed image such that the determined maximum values ​​associated with each pixel in the multiple masked images are represented in the single observed image. In other embodiments, one or more processors of computing system 160 may generate a single observed image such that the determined minimum values ​​associated with each pixel in the multiple masked images are represented in the single observed image. In yet another embodiment, one or more processors of computing system 160 may generate two single observed images, including one single observed image representing the determined maximum values ​​and one single observed image representing the determined minimum values.

[0138] As an example, Fig.24 A generated single observed image 250 having a plurality of pixels P is depicted. Notably, the pixels P of the single observed image 250 represent or depict the same corresponding portion of the part 200 as they do in the masked image 290 and the captured image 260. Thus, throughout the single observed image generation process, a particular pixel always represents the same portion of the part 200. For example, pixel P12 may represent the same portion of the part 200 in the captured image, in the generated masked image, and in the captured image 260. Fig.24 A portion of the leading edge of component 200 in final single observed image 250 is shown.

[0139] Each pixel P of the single observed image 250 representing a portion of the component 200 displays its respective portion of the component 200 and the transient thermal response of the component 200. The transient thermal response of the component 200 is represented in the pixel P of the single observed image 250 as the determined maximum value of the corresponding pixel. For example, the determined maximum value of the pixel P10 of the single observed image 250 is determined as T3 (e.g., which is obtained from Fig.23 290F in the third mask image 290F). Thus, in the single observed image 250, the thermal response of the component 200 at the pixel P10 is depicted as T3. The determined maximum value of the pixel P11 of the single observed image 250 is determined as T2 (e.g., which is derived from Fig.23 Thus, in the single observed image 250, the thermal response of the component 200 at the pixel P11 is depicted or represented as T2. The other pixels P of the single observed image 250 may also represent their respective determined maximum values.

[0140] It is worth noting that the heating element 112 ( Fig.19 ) does not exist or is almost removed in the generated single observed image 250. Since pixels are selected from the pixels of the mask image 290 to ultimately display their maximum values, the heating element 112 does not exist in the single observed image 250. Therefore, although the imaging camera 152 ( Figure 1 ) in the plurality of captured images 260 ( Figure 15-18 ), but the single observed image 250 does not include the footprint of the heating element 112. This can provide a clearer image and can facilitate the detection of defects and analysis of thermal response of the component 200, for example at (314), (316), and (318) of the method (300) described herein.

[0141] The technology discussed herein refers to computer-based systems, actions taken by computer-based systems, information sent to computer-based systems, and information from computer-based systems. It should be understood that the inherent flexibility of computer-based systems allows for a variety of possible configurations, combinations, and divisions of tasks and functions between and within components. For example, a single computing device or multiple computing devices working in combination can be used to implement the processing discussed herein. Databases, memories, instructions, and applications can be implemented on a single system or distributed on multiple systems. Distributed components can operate sequentially or in parallel.

[0142] Although specific features of various embodiments may be shown in some drawings and not in other drawings, this is for convenience only. According to the principles of the present disclosure, any feature of a drawing may be referenced and / or claimed in combination with any feature of any other drawing.

[0143] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any device or system and performing any incorporated method. The patentable scope of the invention is defined by the claims, and may include other examples that occur to one skilled in the art. These other examples are intended to fall within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that do not differ substantially from the literal language of the claims.

[0144] Further aspects of the invention are provided by the subject matter of the following clauses:

[0145] 1. A system comprising: a heating element; an imaging system having an imaging device; a computing system having one or more processors and one or more memory devices, the one or more processors being configured to: cause the heating element to traverse relative to a component having a coating; cause the heating element to heat the component as the heating element traverses relative to the component; cause the imaging device to capture a plurality of images of the component as the heating element traverses relative to the component and applies heat thereto, the plurality of captured images indicating a transient thermal response of the component; and detect one or more coating defects in the coating of the component based at least in part on the transient thermal response of the component captured in the plurality of images.

[0146] 2. A system according to any of the preceding clauses, wherein the one or more processors are constructed to: generate a single image from the multiple captured images, the single image indicating one or more detected coating defects in the coating of the component, and wherein the one or more processors use the generated single image to detect the one or more coating defects in the coating of the component.

[0147] 3. A system according to any preceding clause, wherein the one or more processors cause the heating element to traverse relative to the component at a speed between 2-5 cm / s.

[0148] 4. A system according to any preceding clause, wherein when detecting the one or more coating defects in the coating of the component based at least in part on the transient thermal response of the component captured in the plurality of images, the one or more processors are configured to: identify one or more regions of the coating where the transient thermal response is outside of a predetermined range, and wherein the one or more regions of the coating where the transient thermal response is outside of the predetermined range are identified as the one or more coating defects of the coating.

[0149] 5. A system according to any of the preceding clauses, wherein the one or more processors are configured to: determine one or more characteristics of the identified one or more coating defects of the coating; and classify the identified one or more coating defects of the coating based at least in part on the one or more determined characteristics.

[0150] 6. A system according to any of the preceding clauses, wherein when determining the one or more characteristics of the one or more coating defects of the identified coating, the one or more processors are constructed to: determine at least one of the following: the number of the one or more coating defects of the identified coating, the depth of each of the one or more coating defects of the identified coating, and the area fraction of the one or more coating defects of the identified coating.

[0151] 7. A system according to any of the preceding clauses, wherein the one or more processors are configured to: determine whether the coating of the component is an acceptable coating based on at least one of the following comparisons: a comparison of the number of one or more coating defects of the coating identified to a number threshold; a comparison of the depth of each of the one or more coating defects of the coating identified to a depth threshold; and a comparison of the area fraction of the one or more coating defects of the coating identified to an area fraction threshold.

[0152] 8. A system according to any of the preceding clauses, further comprising: an airflow generator, which is fluidly connected to the component, and wherein the one or more processors are constructed to cause the airflow generator to pulse airflow through one or more internal channels of the component when the heating element traverses the component and applies heat to it.

[0153] 9. The system of any preceding clause, wherein the component is a metallic component and the coating is a thermal barrier coating.

[0154] 10. A system according to any preceding clause, wherein the imaging device is at least one of a medium wavelength imaging camera and a long wavelength imaging camera, wherein the medium wavelength imaging camera captures wavelengths in the range of approximately three to six microns and the long wavelength imaging camera captures wavelengths in the range of approximately six to fourteen microns.

[0155] 11. A system according to any preceding clause, wherein the imaging device is operably configured to detect defects as small as 80 microns.

[0156] 12. A method comprising: traversing a heating element relative to a component having a coating; heating the component using the heating element as the heating element traverses relative to the component; capturing a plurality of images of the component using an imaging device as the heating element traverses relative to and applies heat to the component, the captured plurality of images indicating a transient thermal response of the component; and detecting one or more coating defects in the coating of the component based at least in part on the transient thermal response of the component captured in the plurality of images.

[0157] 13. The method of any preceding clause, further comprising pulsing an air flow through an internal passage defined by the component as the heating element traverses relative to the component and applies heat thereto.

[0158] 14. A method according to any preceding clause, wherein detecting the one or more coating defects in the coating of the component based at least in part on the transient thermal response of the component captured in the plurality of images comprises: identifying one or more regions of the coating having the transient thermal response outside of a predetermined range, and wherein the one or more regions of the coating having the transient thermal response outside of the predetermined range are identified as the one or more coating defects of the coating.

[0159] 15. The method according to any preceding clause, further comprising: generating a single image from the captured multiple images, the single image indicating one or more detected coating defects in the coating of the component, and wherein the one or more coating defects in the coating of the component are detected using the generated single image.

[0160] 16. The method according to any of the preceding clauses, further comprising: determining one or more characteristics of the one or more coating defects of the coating detected; and classifying the one or more coating defects of the coating detected based at least in part on the one or more determined characteristics.

[0161] 17. A non-transitory computer-readable medium comprising computer-executable instructions which, when executed by one or more processors of a computing system of a coating inspection system, cause the one or more processors to: cause a heating element of the coating inspection system to traverse relative to a component having a coating; cause the heating element to heat the component as the heating element traverses relative to the component; cause an imaging device of the coating inspection system to capture a plurality of images of the component as the heating element traverses relative to the component and applies heat thereto, the plurality of captured images indicating a transient thermal response of the component; and detect one or more coating defects in the coating of the component based at least in part on the transient thermal response of the component captured in the plurality of images.

[0162] 18. A computer-readable medium according to any of the preceding clauses, wherein when the computer-executable instructions are executed by one or more processors of the computing system of the coating inspection system, the one or more processors are further caused to: when the heating element traverses relative to the component and applies heat to it, cause an airflow generator in fluid communication with the component to pulse airflow through one or more internal channels of the component.

[0163] 19. A computer-readable medium according to any preceding clause, wherein when the computer-executable instructions are executed by the one or more processors of the computing system of the coating inspection system, the one or more processors are further caused to: generate a single image from the multiple captured images, the single image indicating one or more detected coating defects in the coating of the component, and wherein the one or more processors use the generated single image to detect the one or more coating defects in the coating of the component.

[0164] 20. The computer-readable medium of any preceding clause, wherein the heating element traverses relative to the component and applies heat thereto without contacting the component.

Claims

1. A system, characterized in that: include: Heating elements; an airflow generator in fluid communication with the component; An imaging system, the imaging system comprising an imaging device; A computing system having one or more processors and one or more memory devices, wherein the one or more processors are configured to: traversing the heating element relative to the component having the coating; causing the heating element to heat the component as the heating element traverses relative to the component; causing the airflow generator to pulse airflow through one or more interior passages of the component as the heating element traverses relative to the component and applies heat thereto; causing the imaging device to capture a plurality of images of the component as the heating element traverses relative to the component and applies heat thereto, the plurality of captured images being indicative of a transient thermal response of the component; as well as One or more coating defects in the coating of the component are detected based at least in part on the transient thermal response of the component captured in the plurality of images.

2. The system according to claim 1, characterized in that The one or more processors are configured to: generating a single image from the plurality of captured images, the single image being indicative of one or more detected coating defects in the coating of the component, and Wherein the one or more processors use the generated single image to detect the one or more coating defects in the coating of the component.

3. The system according to claim 1, characterized in that The one or more processors cause the heating element to traverse relative to the component at a speed between 2-5 cm / s.

4. The system according to claim 1, characterized in that wherein in detecting the one or more coating defects in the coating of the component based at least in part on the transient thermal response of the component captured in the plurality of images, the one or more processors are configured to: identifying one or more regions of the coating where the transient thermal response is outside a predetermined range, and wherein the one or more regions of the coating having the transient thermal response outside the predetermined range are identified as the one or more coating defects of the coating.

5. The system according to claim 4, characterized in that The one or more processors are configured to: determining one or more characteristics of the identified one or more coating defects of the coating; and The identified one or more coating defects of the coating are classified based at least in part on the one or more determined characteristics.

6. The system according to claim 4, characterized in that wherein in determining the one or more characteristics of the identified one or more coating defects of the coating, the one or more processors are configured to: At least one of: a number of the identified one or more coating defects of the coating, a depth of each of the identified one or more coating defects of the coating, and an area fraction of the identified one or more coating defects of the coating is determined.

7. The system according to claim 6, characterized in that The one or more processors are configured to: Determining whether the coating of the component is an acceptable coating is based on at least one of the following comparisons: a comparison of said number of one or more coating defects of said coating identified with a number threshold; a comparison of the depth of each of the identified one or more coating defects of the coating to a depth threshold; as well as A comparison of the area fraction of the identified one or more coating defects of the coating to an area fraction threshold value.

8. The system according to claim 1, characterized in that Wherein the component is a metal component and the coating is a thermal barrier coating.

9. The system according to claim 1, characterized in that Wherein the imaging device is at least one of a medium wavelength imaging camera and a long wavelength imaging camera, wherein the medium wavelength imaging camera captures wavelengths in the range of three to six microns and the long wavelength imaging camera captures wavelengths in the range of six to fourteen microns.

10. The system according to claim 1, characterized in that Wherein the imaging device is operably configured to detect defects as small as 80 microns.

11. A method, characterized in that include: traversing a heating element relative to the component having the coating; heating the component using the heating element as the heating element traverses relative to the component; pulsing an air flow through an internal passage defined by the component as the heating element traverses relative to the component and applies heat thereto; capturing, using an imaging device, a plurality of images of the component as the heating element traverses relative to the component and applies heat thereto, the plurality of images captured being indicative of a transient thermal response of the component; as well as One or more coating defects in the coating of the component are detected based at least in part on the transient thermal response of the component captured in the plurality of images.

12. The method according to claim 11, characterized in that Wherein detecting the one or more coating defects in the coating of the component based at least in part on the transient thermal response of the component captured in the plurality of images comprises: identifying one or more regions of the coating where the transient thermal response is outside a predetermined range, and wherein the one or more regions of the coating having the transient thermal response outside the predetermined range are identified as the one or more coating defects of the coating.

13. The method according to claim 11, characterized in that Further including: generating a single image from the captured plurality of images, the single image being indicative of one or more detected coating defects in the coating of the component, and wherein the one or more coating defects in the coating of the component are detected using the generated single image.

14. The method according to claim 11, characterized in that Further including: determining one or more characteristics of one or more detected coating defects of the coating; and One or more detected coating defects of the coating are classified based at least in part on the one or more determined characteristics.

15. A non-transitory computer-readable medium, characterized in that The non-transitory computer readable medium includes computer executable instructions that, when executed by one or more processors of a computing system of a coating inspection system, cause the one or more processors to: traversing a heating element of the coating inspection system relative to a component having a coating; causing the heating element to heat the component as the heating element traverses relative to the component; causing an airflow generator in fluid communication with the component to pulse airflow through one or more internal passages of the component as the heating element traverses relative to the component and applies heat thereto; causing an imaging device of the coating inspection system to capture a plurality of images of the component as the heating element traverses relative to the component and applies heat thereto, the plurality of captured images being indicative of a transient thermal response of the component; as well as One or more coating defects in the coating of the component are detected based at least in part on the transient thermal response of the component captured in the plurality of images.

16. The computer-readable medium of claim 15, wherein: wherein when the computer executable instructions are executed by the one or more processors of the computing system of the coating inspection system, further cause the one or more processors to: generating a single image from the plurality of captured images, the single image being indicative of one or more detected coating defects in the coating of the component, and Wherein the one or more processors use the generated single image to detect the one or more coating defects in the coating of the component.

17. The computer-readable medium of claim 15, wherein: The heating element traverses relative to the component and applies heat thereto without contacting the component.

Images