X-ray imaging device

Abstract

An X-ray imaging device (110) for imaging a helicopter rotor blade (20) mounted on a helicopter, the device comprising an upper arm (140), a lower arm (150), and a connecting member (145) for maintaining the upper arm and the lower arm in a stationary state relative to each other, one of the upper arm and the lower arm including at least one X-ray source (141), the other of the upper arm and the lower arm including a digital X-ray detector, the device including moving means (160, 170) for moving the device relative to the blade during use and a control device configured to control the X-ray source and the X-ray detector such that a plurality of three-dimensional X-ray images of the blade can be generated during use.

Description

Technical Field

[0001] The present invention generally relates to an X-ray imaging apparatus and method for generating three-dimensional X-ray images, and although not limited thereto, has found particular utility in generating X-ray images of helicopter rotor blades.

Background Art

[0002] Helicopter rotor blades are very sophisticated products consisting of various materials and combinations of composites. Each rotor blade can be manufactured as a composite including a foam or honeycomb material forming the core of the blade. The blade can be covered on the outside by one or more layers of fiber-reinforced plastic. For further reinforcement, carbon, Kevlar® or glass fibers can be used in areas of very high stress, such as the trailing edge, and other complex parts, such as the "rear wall corner connection" of the composite frame, or the "foam stress part" of the foam within the front part of the blade.

[0003] Continual exposure to significant load spectra often results in damage to the rotor blades and continuous and regular inspections are required to ensure the continued availability of the helicopter and the safe operation of the helicopter. However, the inspection of these structures is not straightforward, especially for internal structures, due to the complexity of the design and the innumerable materials used, with the shape and different material properties and anisotropy making the inspection difficult.

[0004] Several studies have investigated the usefulness of structural health monitoring (SHM) methods for detecting and characterizing damage associated with continuous flight cycles, but conventional non-destructive testing (NDT) modalities, such as ultrasonic inspection, bond inspection, and simple tap testing, are still useful and continue to be used.

[0005] The rotor blades are routinely visually inspected to detect surface cracks and corrosion. Manual acoustic inspection is performed by tapping the rotor blades with a hammer and recording the impact sound to determine whether the joints of the substructures are intact or separated. This inspects for delamination between the alloy coating and the leading edge spar or root reinforcement strip. These inspections are time-consuming, cannot be automated, and can cause errors at a high rate. Furthermore, these inspections make it very difficult to detect any damage that is not visible from the outside. These conventional NDT methods continue to be essential tools for establishing the ongoing safety of helicopters in operating facilities and, further, in maintenance, repair, and disassembly inspection facilities. These conventional NDT methods are used to accurately indicate the damage location to guide the repair process in order to minimize the removal of non-damaged components and materials and, further, to ensure that the repair is effective.

[0006] Devices are known that use computed radiography where an image is captured on a flexible and reusable imaging plate coated with a fluorescent material. The imaging plate is then scanned by a laser scanner that generates a digital image. Other known devices use fluoroscopy or real-time radiography (RTR), where radio waves are emitted into one side of the material and a sensor on the other side converts the rays to light and generates a digital image that reveals corrosion and internal / external defects in real time. The known methods only generate 2D images.

[0007] Large units are known that generate 3D X-ray images. However, for certain components mounted on, for example, a helicopter, the component needs to be removed before it can be scanned. Furthermore, due to the X-ray power required to achieve good image quality, the device has to be shielded in a bunker, which means that the object is limited to a size of approximately 2m x 2m. Helicopter blades do not fit within such known devices.

Summary of the Invention

Problems to be Solved by the Invention

[0008] Therefore, there is a need for a device for generating 3D X-ray images of relatively large objects such as helicopter rotor blades and for removing them from their attachment points to other objects such as helicopters without the need to remove them.

Means for Solving the Problems

[0009] In a first aspect, the present invention provides an X-ray imaging device for imaging a helicopter rotor blade mounted on a helicopter, the device comprising an upper arm, a lower arm, and a connecting member for maintaining the upper arm and the lower arm in a stationary state relative to each other, one of the upper arm and the lower arm including at least one X-ray source, the other of the upper arm and the lower arm including a digital X-ray detector, the device further including moving means for moving the device relative to the blade during use, and a control device configured to control the X-ray source and the X-ray detector such that a plurality of three-dimensional X-ray images of the blade can be generated during use.

[0010] By this method, the blade can be exposed to X-rays without the need to remove the blade from the helicopter. During use, the device can be lifted into place from the ground by a typical lifting device such as a scissor lift, cherry picker, crane, etc.

[0011] The moving means for moving the device relative to the blade during use may include blade engaging means for driving the device across a first outer surface and / or a second outer surface of the blade. For example, wheels, tracks, and other ground engaging means may be used. By this method, the device can be considered self-propelled and / or portable.

[0012] The X-ray imaging device can be configured to be fully supported by the wings during use. This can be achieved due to the relatively lightweight nature of the device. The use of a flat panel emitter that uses equipment with a relatively low power rating to switch the X-ray emitters in the array on and off can achieve this relatively lightweight nature.

[0013] The X-ray imaging device can include ground support means, and the moving means for moving the device relative to the wings during use can include ground engaging means for moving the device along the surface where the helicopter can be positioned during use.

[0014] For example, a scaffold supported on a movable trolley can be provided, which includes a device located above the height of the surface and supported by the scaffold to access the wings. The trolley is movable along the surface and thus can include ground engaging means for moving the device relative to the wings.

[0015] The ground support means can include a scissor lift for raising and lowering the X-ray source and the X-ray detector relative to the ground during use.

[0016] The X-ray imaging device can further include a tape attachable to the wings, and the tape includes a reference marker for providing an indication of the position of the device relative to the wings during use by providing a marker in the generated X-ray image. The tape can provide a mark in the X-ray image so that the position of the image relative to the wings can be determined.

[0017] The X-ray imaging device can further include a processor for receiving data from the X-ray detector and for generating an image of the wings.

[0018] The control device can be configured to control the moving means. By this method, the control device can move the device to various positions so that the entire wing is imaged.

[0019] The X-ray source may comprise an array of X-ray emitters. The X-ray source may comprise at least one flat panel source. The X-ray imaging device may be configured to generate 2D and / or 3D X-ray images.

[0020] The X-ray imaging device may include X-ray source moving means for moving at least one X-ray source relative to the upper or lower arm. Similarly, the X-ray imaging device may include X-ray detector moving means for moving the X-ray detector relative to the upper or lower arm.

[0021] In this approach, if at least one X-ray source can only image a relatively small portion of the blade at any one time, the arm may remain stationary relative to the blade and the at least one X-ray source and / or detector may be moved relative to the arm to image other portions of the blade before the device is moved to a new stationary position for imaging other areas of the blade. In this approach, the at least one X-ray source and X-ray detector may be relatively small and thus relatively lightweight and inexpensive.

[0022] In a second aspect, the present invention provides a method of generating a three-dimensional X-ray image of a rotor blade mounted on a helicopter, the method comprising the steps of providing a device according to the first aspect; arranging the device in a first position relative to the blade such that the X-ray source is on one side of the blade and the X-ray detector is on the other side of the blade; operating the device to emit X-rays from the X-ray source and detect the X-rays with the X-ray detector so as to generate an image; moving the device to a second subsequent position relative to the blade; and operating the device to emit X-rays from the X-ray source and detect the X-rays with the X-ray detector so as to generate a further second subsequent image.

[0023] The method may further comprise generating X-ray images of at least one portion of the blade at iterative intervals and comparing the images to provide an indication of a suspected structural defect and / or damage in the blade.

[0024] The method may further include moving the device over the width and length of the wing in incremental steps, and operating the X-ray source and X-ray detector at each step to generate a plurality of images.

[0025] The method may further include using an image recognition method to concatenate the X-ray images together such that the processor generates one image of a larger portion of the wing.

[0026] The above and other characteristics, features, and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings that illustrate the principles of the invention. This description is given for the purpose of illustration only and does not limit the scope of the invention. The reference drawings cited below represent the accompanying drawings.

Brief Description of the Drawings

[0027]

Figure 1

Figure 2

[0028] Although the present invention is described in relation to specific drawings, the present invention is not limited thereto and is limited only by the claims. The drawings described are only schematic and not limiting. Each drawing does not necessarily include all the features of the invention and thus is not necessarily considered to be an embodiment of the invention. In the drawings, the sizes of some of the elements may be exaggerated for purposes of illustration and may not be drawn to scale. The dimensions and relative dimensions do not correspond to actual reductions of the embodiments of the invention.

[0029] Furthermore, the terms first, second, third, etc. in this description and the claims are used to distinguish similar elements and are not necessarily used to describe an order in terms of time, space, sequence, or any other method. It is understood that such terms are interchangeable with each other in appropriate circumstances and that the operation is possible in other orders different from those described or illustrated herein. Similarly, method steps described in a particular order or recited in the claims may be understood to operate in a different order.

[0030] Furthermore, terms such as upper, lower, above, below, etc. in this description and the claims are used for illustrative purposes and are not necessarily used to describe a relative position. It is understood that such terms are interchangeable with each other in appropriate circumstances and that the operation is possible in other orientations different from the orientation described or illustrated herein.

[0031] It should be noted that the expressions such as "comprising" used in the claims should not be construed as being limited to the means listed thereafter, and the expressions such as "comprising" do not exclude other elements and steps. Therefore, the expression "comprising" is construed to specify the presence of the described features, integers, steps, or components as stated, without excluding the presence or addition of one or more other features, integers, steps, or components, or groups thereof. Therefore, the scope of the expression "a device comprising means A and B" should not be limited to a device consisting only of components A and B. In the context of the present invention, "a device comprising means A and B" simply means that the relevant components of the device are A and B.

[0032] Similarly, it should be noted that the term "connected" as used in this description should not be construed as being limited to direct connections only. Thus, the scope of the expression "device A connected to device B" should not be limited to a device or system where the output of device A is directly connected to the input of device B. The expression "device A connected to device B" means that there exists a path, which may be a path including other devices or means, between the output of A and the input of B. "Connected" can mean that two or more elements are in direct physical or electrical contact, or that two or more elements are not in direct contact with each other but still cooperate or interact with each other. For example, wireless connectivity is assumed.

[0033] References to "embodiments" or "aspects" in this specification mean that the particular features, structures, or characteristics described in connection with the embodiments or aspects are included in at least one embodiment or aspect of the invention. Thus, the use of the expressions "in one embodiment", "in an embodiment", or "in an aspect" in various places in this specification is not necessarily all related to the same embodiment or aspect, and may represent different embodiments or aspects. Further, the particular features, structures, or characteristics of any one embodiment or aspect of the invention may be combined, in any suitable manner, with any other particular features, structures, or characteristics of any other embodiment or aspect of the invention, as will be apparent to those skilled in the art from this disclosure.

[0034] Similarly, in this description, for the purpose of simplifying the present disclosure and facilitating the understanding of one or more of the various aspects of the invention, it should be understood that various features of the invention may be grouped together in one embodiment, figure, or description thereof. However, this method of disclosure is not to be construed as reflecting an intention that the invention as claimed requires more features than are expressly recited in each claim. Further, the description of any individual drawing or aspect is not necessarily to be considered as an embodiment of the invention. Rather, as the claims hereinafter show, aspects of the invention lie in less than all of the features of one of the previously disclosed embodiments. Accordingly, the claims following the detailed description are expressly incorporated herein into this detailed description, and each claim stands on its own as a separate embodiment of the invention.

[0035] Furthermore, while some embodiments described herein include some features that are included in other embodiments, combinations of features of different embodiments are intended to be within the scope of the invention and, as will be understood by those skilled in the art, form still further different embodiments. For example, in the claims hereinafter, any of the embodiments described in the claims may be used in any combination.

[0036] In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this description.

[0037] In the discussion of the present invention, unless otherwise stated, the disclosure of alternative values for the upper or lower limits of acceptable range of parameters, which are associated with an indication that one of the values is much more preferable than the others, shall be construed as an implicit statement that each of the intermediate values of the parameters between the alternative relatively preferable values and the less preferable values is more preferable than the less preferable values, and further more preferable than each of the values between the less preferable values and the intermediate values.

[0038] The use of the term "at least one" may mean only one in a particular situation. The use of the term "any" may mean "all" and / or "each" in a particular situation.

[0039] The principles of the present invention will be described below by way of a detailed description of at least one drawing related to exemplary features. It is apparent that other configurations can be constructed based on the knowledge of those skilled in the art without departing from the underlying concepts or technical teachings, and the present invention is limited only by the language of the appended claims.

[0040] In FIG. 1, an X-ray imaging apparatus 10 is shown. It includes a C-arm 30 including an upper arm 40, a lower arm 50, and a connection part 45.

[0041] The C-arm 30 is arranged around the rotor blade 20 such that the upper arm 40 is above the upper surface of the rotor blade 20 and the lower arm 50 is below the rotor blade. The helicopter with the rotor blade 20 mounted thereon is not shown but is to the left of the figure.

[0042] Typically, a predetermined size of gap is maintained between the blade 20 and the upper arm, and between the blade and the lower arm. The connection part is located on one side of the rotor blade 20. The connection part 45 always maintains the position of the upper arm 40 relative to the lower arm 50. By this method, the C-arm 40 can move relatively along the longitudinal direction of the rotor blade 20.

[0043] The C-arm 30 is supported in a state separated from the ground by a support means 110 schematically shown as a scissor lift. The support means 110 may take different forms, such as, for example, a hydraulic ram or other such devices with adjustable C-arm height.

[0044] The support means 110 is located on a trolley 80 including a base 90 for its movement and four wheels 100.

[0045] The support means may be configured to lift and / or lower the C-arm 30 above the trolley 80 in order to position the C-arm 30 around the wing 20.

[0046] The control device 60 is connected to the C-arm by a cable 50 and is disposed on the trolley, but the control device may also be disposed on the C-arm or separated from the device 10.

[0047] The upper arm 40 includes one or more X-ray emitters, and the lower arm 50 includes a digital X-ray detector. It is assumed that these positions may be reversed if desired. During use, the control device 60 controls the X-ray emitter to emit X-rays through the wing 20 so that the X-rays are detected by the detector in the lower arm 50.

[0048] During use, the trolley 80 is movable along the length direction of the wing 20 so that the entire wing 20 can be imaged by this method.

[0049] The C-arm 30 can be sized so that the full width of the wing 20 fits below the upper arm 40 and above the lower arm 50. In this regard, the term "width" may mean the dimension extending orthogonally to the full length in the longitudinal direction of the wing 20 in a plane parallel to the ground surface.

[0050] Alternatively, if the width of the wing is too large to fit completely below the upper arm, the device 10 can be displaced relative to the wing 20 such that the open end of the C-arm comes to the opposite side of the wing compared to that shown in FIG. 1.

[0051] Wheels 100 are arranged on both sides of the trolley such that the trolley 80 is movable along the entire longitudinal length of the rotating wing 20. However, it is envisioned that other wheels or means of movement may be included instead of, or in addition to, the shown wheels 100. By this approach, the trolley 80 can be more easily positioned. For example, a continuous track may be provided. The wheels may be motor-driven such that during use the trolley 10 moves along the entire longitudinal length below the wing 20. The wheels may be replaced by a continuous track. The wheels / track may be controllable such that the device 10 is movable not only along the entire longitudinal length of the wing 20 but also positionable in the width direction of the wing.

[0052] The device 110 can be controlled such that the speed of movement of the device 110 relative to the wing 20 matches the speed of image capturing of the device 110.

[0053] Furthermore, the support means 110 may be rotatable about a vertical axis relative to the trolley deck 90 such that the open end of the C-arm 30 can be positioned relative to the wing 20 as required. For example, the device 10 is configured such that no force is applied to the wing 20 during imaging by contact of the device 10 with the wing 20.

[0054] A tape 120 is shown disposed along the upper surface of the entire longitudinal length of the wing 20. The tape 120 includes reference markers recognizable by X-rays such that the position of the image relative to the wing is recognized when included in the X-ray image.

[0055] The device 10 can be controlled such that the speed of movement of the device 10 relative to the wing 20 matches the speed of image capturing of the device 10. The device may be configured to stop at each X-ray image acquisition site.

[0056] The device 10 is configured to move in all directions in a horizontal plane parallel to the ground surface.

[0057] Figure 2 shows an end view of an alternative device 110. The wing 20 is horizontally positioned between the upper arm 140 and the lower arm 150. The two arms 140, 150 are attached together by a connecting member 145 disposed on the side of the wing 20. The connecting member 145 always maintains the position of the upper arm 140 relative to the lower arm 150. The upper arm includes wheels 160 disposed downward such that they are positioned on the upper surface of the wing 20 during use. Similarly, the lower arm 150 includes wheels 160 disposed upward such that they contact the lower surface of the wing 20 during use.

[0058] The upper arm 140 includes one or more X-ray sources / emitters 141, and the lower arm 150 includes a digital X-ray detector. It is contemplated that the source / emitter may be disposed on the lower arm and the detector may be disposed on the upper arm. If desired, during use, the control device controls the X-ray emitter to emit X-rays 180 through the wing 20 such that the X-rays 180 are detected by the detector in the lower arm 150.

[0059] The wheels 160, 170 function to maintain one or more X-ray emitters at a predetermined distance away from the upper surface of the wing 20. Similarly, the wheels maintain the detector at a predetermined distance away from the lower surface of the wing 20.

[0060] The wheels 160, 170 are motor-driven so that the device 110 moves along the entire longitudinal length of the wing 20 during use. The wheels may be replaced with a continuous track. The wheels / track may be steerable such that the device 110 is not only movable along the entire longitudinal length of the wing 20, but also is positionable in the width direction of the wing such that the entire width of the wing is imageable.

[0061] The device 110 may be controlled such that the speed of movement of the device 110 relative to the wing 20 is adapted to the speed of image capturing of the device 110.

[0062] The device 110 is configured to move in all directions within a horizontal plane parallel to the ground surface. The device may be configured to stop at each X-ray image acquisition site.

[0063] The device 110 may include means for varying the distance of the upper arm and / or the lower arm from the upper surface and / or the lower surface of the wing, for example, by using adjustable wheels or a truck suspension system, in order to accommodate wings having, for example, no uniform thickness or profile.

[0064] The X-ray source / emitter 141 is shown as extending only over a part of the width of the upper arm 140. This X-ray source / emitter 141 may be movable relative to the upper arm to other positions across the width of the upper arm 140 by, for example, X-ray source moving means such as an electric motor. A second position 142 is shown to the right of the first position 141.

[0065] Alternatively, the X-ray source / emitter may be arranged across the entire width of the upper arm 140.

[0066] Although not shown in FIG. 2, tape may be applied to the surface of the wing by a similar method. And it is understood that it may be applied to the tape 20 described with reference to FIG. 1 for the same reason.

[0067] Images generated by using any of the devices 10, 110 may be "stitched" together using a computer processing method to generate a larger image. The reference markers in the tape 120 may assist in this process. In this regard, the devices 10, 110 may include a processor for generating an image from the signals provided by the detector.

[0068] The images may be in 2D or 3D tomosynthesis form.

[0069] Any of the devices 10, 110 may include a geographical location information device such as a GPS to assist in the identification of the device's placement and the resulting images.

Claims

1. An X-ray imaging device for imaging a helicopter rotor blade mounted on a helicopter, the device comprising: an upper arm, a lower arm, a connecting member for maintaining the upper arm and the lower arm in a stationary state relative to each other, and comprising: one of the upper arm and the lower arm includes at least one X-ray source, the other of the upper arm and the lower arm includes a digital X-ray detector, the device includes moving means for moving the device relative to the blade during use, and a control device configured to control the X-ray source and the X-ray detector, such that a plurality of three-dimensional X-ray images of the blade can be generated during use. An X-ray imaging device.

2. The moving means for moving the device relative to the blade during use includes blade engagement means for driving the device across a first outer surface and / or a second outer surface of the blade. The X-ray imaging device according to claim 1.

3. Configured to be fully supported by the blade during use. The X-ray imaging device according to any one of claims 1 and 2.

4. Including ground support means, the moving means for moving the device relative to the blade during use includes ground engagement means for moving the device along a surface of the ground on which the helicopter can be positioned during use. The X-ray imaging device according to claim 1.

5. The ground support means includes a scissor lift for raising and lowering the X-ray source and the X-ray detector relative to the ground during use. The X-ray imaging device according to claim 4.

6. Further comprising a tape attachable to the wing, the tape including a reference marker for providing an indication of the position of the apparatus relative to the wing during use by providing a marker in the generated X-ray image. An X-ray imaging apparatus according to any one of claims 1 to 5.

7. Further comprising a processor for receiving data from the X-ray detector and for generating an image of the wing. An X-ray imaging apparatus according to any one of claims 1 to 6.

8. The control device is configured to control the moving means. An X-ray imaging apparatus according to any one of claims 1 to 7.

9. The X-ray source comprises an array of X-ray emitters. An X-ray imaging apparatus according to any one of claims 1 to 8.

10. The X-ray source comprises at least one flat panel source. The X-ray imaging apparatus according to claim 9.

11. Including X-ray source moving means for moving at least one of the X-ray sources relative to the upper arm or the lower arm. An X-ray imaging apparatus according to any one of claims 1 to 10.

12. Including X-ray detector moving means for moving the X-ray detector relative to the upper arm or the lower arm. An X-ray imaging apparatus according to any one of claims 1 to 11.

13. A method for generating a three-dimensional X-ray image of a rotor blade mounted on a helicopter, the method comprising: Providing an apparatus according to any one of claims 1 to 12; Placing the device at a first position relative to the wing such that the X-ray source is on one side of the wing and the X-ray detector is on the other side of the wing; Operating the device to emit X-rays from the X-ray source and detect the X-rays with the X-ray detector to generate an image; Moving the device to a second subsequent position relative to the wing; Operating the device to emit X-rays from the X-ray source and detect the X-rays with the X-ray detector to generate a further second subsequent image; A method comprising. "Claim 14" Generating X-ray images of at least one part of the wing at repetitive intervals; Comparing the images to provide an indication of a suspected structural defect and / or damage in the wing; The method according to claim 13, further comprising. "Claim 15" Moving the device incrementally across the width and length of the wing; Operating the X-ray source and the X-ray detector in each said step to generate a plurality of images; The method according to any one of claims 13 and 14, further comprising. "Claim 16" The method according to any one of claims 13 to 15, further comprising a processor using an image recognition method and concatenating the X-ray images together to generate an image of a larger part of the wing. The method according to any one of claims 13 to 15.

Images