1. Field of the Invention
The present invention relates to a method for visualizing the arrangement of the internal structure of a structure which has load-bearing structural members provided on the inside.
2. Description of the Related Art
To ensure the safety of aircraft operation, various inspections are conducted while the aircraft is parked. Among these inspections is a visual inspection, in which damage caused in the airframe of the aircraft, e.g., in the wing, is detected, and repair is performed on the basis of the detection result. If a hole is left in the wing, work for closing this hole is performed using a repair member.
In this repair work, depending on the extent of damage, it is necessary to mount on the wing a jig for fixing the repair member to the wing, and this jig can reach inside the wing as shown in Japanese Patent Laid-Open No. 2014-188994 (FIG. 2), for example.
The wing includes a skin which is an outermost layer, and structural members, such as ribs and stringers, which are provided on the inside surrounded by the skin and resist loads applied to the wing. To maintain the soundness of these structural members, it is necessary to prevent the jig required for repair work from interfering with the structural members even when the jig penetrates the skin and reaches inside the wing. Conversely, it is also sometimes necessary to fix the jig using the internal structural members.
It is therefore an object of the present invention to provide a method for visualizing, from the outside, the internal structural members which are covered with the skin and therefore not visible to the naked eye.
To achieve the above object, an internal structure visualization method of the present invention is a method applied to a structure, which includes a skin with a front surface and a back surface and structural members supporting the skin from the back surface side, to visualize, when necessary, a trace map composed of lines extending along projection regions of the structural members, wherein a developing element of the trace map is provided along the projection regions of the front surface, and the trace map is displayed by performing a predetermined process on a predetermined region of the front surface where the developing element is provided.
According to the present invention, when necessary, such as during repair, the trace map can be visualized and displayed simply by applying an external stimulus, such as heat or light, to a region including the location of damage. Thus, according to the present invention, interference between the fixing jig and the structural members can be precluded, or the fixing jig can be reliably mounted on the structural members, so that the burden of the repair work can be relieved.
In the visualization method of the present invention, as the developing element, a coating film can be used which is reversibly and repeatedly switched between its colored state and colorless state through application of an external stimulus as the predetermined process and removal of the external stimulus, and the trace map can be visualized on the front surface of the skin.
As such a coating film, a chromic paint can be used which loses its color when subjected to heat or light as the external stimulus and develops its color when the external stimulus is removed. In this case, if the coating film is provided so as to cover the trace map which is visibly drawn on the front surface of the skin, when the coating film develops its color, the trace map is masked thereby, and when the coating film loses its color, the trace map becomes visible there through.
As the coating film, an ultraviolet-reactive paint can also be used which becomes luminous when subjected to ultraviolet light as the external stimulus and loses its color when the ultraviolet light is removed. In this case, if the ultraviolet-reactive paint is provided as a coating film constituting the trace map on the front surface of the skin, when the coating film becomes luminous, the trace map is visualized, and when the coating film loses its color, the trace map disappears.
In the visualization method of the present invention, as the developing element, identification elements can also be used which are provided at a plurality of positions corresponding to the projection regions and each of which includes positional information specifying the position. A predetermined region including these identification elements is imaged as the predetermined process; the positions at which the plurality of identification elements included in the imaged predetermined region are provided are acquired; on the basis of the acquired positional information, image information constituting the trace map to be projected on the predetermined region is generated; and the trace map can be displayed on the basis of the generated image information.
In this visualization method, the trace map can be visualized on one or both of the front surface of the skin and a wearable device.
While the internal structure visualization method of the present invention can be used in arbitrary situations, the method can be applied when repairing a damaged portion of a skin. In this case, a region including the damaged portion of the skin is selected as the predetermined region of the front surface.
While the internal structure visualization method of the present invention can be applied to arbitrary objects, the object can be the airframe of an aircraft.
Thus, when repairing damage caused in the airframe of an aircraft which includes a skin with a front surface and a back surface and structural members supporting the skin from the back surface side, it is possible to perform the repair work with the trace map being displayed by one of the above-described internal structure visualization methods.
According to the present invention, it is possible to visualize and display the arrangement of internal structural members, which are covered with a skin and therefore not visible to the naked eye, as a trace map simply by applying an external stimulus such as heat or light. Thus, according to the present invention, interference between the fixing jig and the structural members can be precluded, or the fixing jig can be reliably mounted on the structural members, so that the burden of the repair work can be relieved.
In the following, preferred embodiments of the present invention will be described using a main wing 2 of an aircraft 1 shown in
The following embodiments include a first embodiment in which the arrangement of internal structural members S of the main wing 2 are drawn in advance on the surface of the main wing 2 using functional lines P, and a second embodiment in which identification information showing the arrangement of the internal structural members S of the main wing 2 is provided on the surface of the main wing 2.
The main wing 2 has the plurality of structural members S, which provide the main wing 2 with strength, provided on the inside at the positions indicated by the dashed lines in
In this embodiment, as indicated by the dot-and-dash lines in
As shown in
In the present invention, the trace map M is displayed only on a certain display region A using the functional lines P which can be reversibly and repeatedly switched between its colored state and colorless state through application and removal of an external stimulus such as light or heat. Specifically, the trace map M is displayed on the display region A by applying an external stimulus, which is required for developing the color of the functional lines P, to the display region A. However, the trace map M may be displayed on an area outside the display region A.
Next, the specific configuration for displaying the trace map through application of an external stimulus to the functional lines P will be described.
First, an example will be described in which a paint having a thermochromism function (hereinafter, “thermochromic paint”) is used as the functional lines P, the thermoschromism function reversibly repeating the cycle of losing its color as an external thermal stimulus is applied thereto and developing its color as the external thermal stimulus is removed therefrom. The chromic molecules composing the chromic paint change in molecule structure under an external stimulus and change accordingly in absorption spectrum in the visible region, which allows the chromic paint to reversibly and repeatedly develop its color and lose its color. A paint which reversibly and repeatedly develops its color and loses its color when the external stimulus is heat is referred to as a thermochromic paint, and a paint which reversibly and repeatedly loses its color and develops its color when the external stimulus is light, especially ultraviolet light, is referred to as a photochromic paint.
To describe the thermochromic paint more specifically, for example, the thermochromic paint remains colored at 40° C. or lower, but when heated to 50° C. or higher, the paint loses its color and becomes transparent. Normally, a color developing temperature T1 is lower than a color losing temperature T2. The color developing temperature T1 of 40° C. and the color losing temperature T2 of 50° C. are mere examples, and some thermochromic paints on the market have the color developing temperature T1 and the color losing temperature T2 adjusted in increments of 5° C.
When the temperature of the aircraft 1 is compared between during flight and after landing, the temperature is lower during flight. Accordingly, if the thermochromic paint is used as is, the entire trace map M would be displayed during flight, while the trace map M would disappear during parking after landing. Therefore, in the case where a thermochromic paint is used to visualize the trace map M, it is desirable that the thermochromic paint itself does not display the trace map M, but instead the functional lines P function as a mask which obscures the trace map M during flight. Nevertheless, the present invention does not exclude the option of visualizing the trace map by developing the color of a thermochromic paint, which has been colorless, through application of cold energy having a temperature equal to or lower than the color developing temperature T1 as an external stimulus.
Here, the first upper coating film C2 and the second coating film C3 have the same color, but the paints used are different from each other: the first upper coating film C2 is a thermochromic paint, and the second coating film C3 is an ordinary paint. Here, an ordinary paint means a paint which does not change its color even when subjected to heat as an external stimulus. The first lower coating film C1 is an ordinary paint and has a different color from the second coating film C3. Accordingly, the first lower coating film C1 serves as the trace map M of the structural members S as will be described below.
In
Using this trace map M as a guide, a repair worker can perform the work so as to avoid interference between the fixing jig and the structural members S, or can correctly mount the fixing jig on the structural members S.
In the example shown in
In the foregoing description, the example in which the trace map is displayed using a chromic paint is shown, but a luminous body which becomes luminous in response to ultraviolet light can also be used as the paint.
An ultraviolet-reactive body is a substance which becomes luminous when subjected to excitation light of near-ultraviolet light having a wavelength of 350 to 400 nm as an external stimulus, and typically the ultraviolet-reactive body becomes luminous blue, yellow, etc. when irradiated with black light. The ultraviolet-reactive body becomes colorless and transparent when ultraviolet light irradiation is stopped. If ultraviolet light is used as an external stimulus, the ultraviolet-reactive body can be used as the functional line P which can be reversibly and repeatedly switched between its luminous state, in which the color is developed, and its colorless state.
Since this ultraviolet-reactive paint is an originally colorless transparent paint which develops its color by being irradiated with ultraviolet light, the ultraviolet-reactive paint is not used as a mask like a chromic paint, but instead, as shown in
As has been described above, in the first embodiment, a paint which is reversibly and repeatedly switched between its colored state and colorless state through application of an external stimulus is provided as the developing element of the trace map on the main wing 2. Therefore, at the time of repair, the trace map can be displayed on the surface of the main wing 2 simply by applying an external stimulus (heat, light) to the display region A including the location of the damage D. Thus, according to this embodiment, interference between the fixing jig and the structural members S can be precluded, or the fixing jig can be reliably mounted on the structural members S, so that the burden of the repair work can be relieved.
Moreover, what is required as the external stimulus is heat or light, and the external stimulus is applied to only a limited area. Thus, the first embodiment can be implemented at any place with simple equipment.
Next, the second embodiment of the present invention will be described with reference to
In the second embodiment, as the element which displays the trace map, identification elements ID which include information specifying the positions of intersection points of the projection regions of the structural members S are arranged at the intersection points on the surface of the main wing 2 as shown in
As shown in
As shown in
The operation of the optical apparatus 5 is controlled by a controller 7 which is a personal computer, for example. In addition to controlling the operation of the optical apparatus 5, the controller 7 analyzes the surface image of the main wing 2 acquired by the imaging function of the optical apparatus 5, and acquires positional information of each identification element ID shown in the image. On the basis of the acquired positional information of the identification elements ID, the controller 7 generates image information constituting the trace map to be projected on the surface of the main wing 2, and moreover commands the optical apparatus 5 to project this trace map based on the image information on the surface of the main wing 2.
To generate the image information constituting the trace map to be projected, the controller 7 retains member-position correspondence information shown in
The member-position correspondence information of
Next, a procedure for displaying the trace map on the main wing 2 provided with the identification elements ID will be described with reference to
First, as shown in
Next, in the case of the example shown in
Here, the identification elements ID are located near the intersection points between the longitudinal and lateral frames, but this is not the only possibility, and it is also acceptable that the identification elements ID are present at positions irrelevant to and different from the positions of the frames, as long as the image information constituting a trace map is related to the identification elements ID.
Next, the controller 7 calculates the distance and direction to the imaged surface of the main wing 2 from the size of each of the plurality of identification elements ID included in the imaging information and the positional relation among these identification elements ID (S105 of
The controller 7 commands the optical apparatus 5 to project the trace map on the main wing 2 on the basis of the generated projection information. Then, upon receiving this command, the optical apparatus 5 projects and visualizes the trace map M on the surface of the main wing 2 as shown in
As has been described above, in the second embodiment, the identification elements ID are provided as the developing element of the trace map on the main wing 2. Therefore, at the time of repair, the trace map can be displayed on the surface of the main wing 2 simply by imaging the display region A including the location of the damage D. Thus, according to this embodiment, interference between the fixing jig and the structural members S can be precluded, or the fixing jig can be reliably mounted on the structural members S, so that the burden of repair work can be relieved.
Since the imaging area and the projection area are not the entire main wing 2 but are limited to only a part of the main wing 2, only the simple optical apparatus 5 needs to be prepared.
While the present invention has been described on the basis of the preferred embodiments, it is possible to selectively adopt the configurations presented in the above embodiments or appropriately modify these configurations into other configurations within the scope of the present invention.
In the first embodiment, visualization of a trace map may be continuously or intermittently performed along the structural members S. The interval in the case of intermittent visualization is desirably shorter than the interval of the intersection points shown in the second embodiment.
In the first embodiment, the width of the structural member S and the width of the first lower coating film C1 and the first upper coating film C2 are equal as shown in
In the second embodiment, it is possible to display locations of past repair in the trace map by including information, which indicates previous repair of the damage D, in the projection information. If it is known that there is a location of past repair near the damage D which is to be repaired, repair of the damage D can be properly performed in consideration of the location of past repair. To realize this, the controller 7 retains the positional coordinates of the locations of past repair which are on the same coordinates as the positional coordinates assigned to the identification elements ID, and checks the positional coordinates corresponding to the locations of past repair against the image information constituting the trace map to find whether or not any positional coordinate corresponding to the locations of past repair is included in the area of the positional coordinates specifying the image information. Then, if any positional coordinate corresponding to the locations of past repair is included, the locations of past repair can be projected on the main wing 2 along with the trace map by including this positional coordinate in the image information constituting the trace map. Moreover, at the time of inspection, damaged portions on record can be visualized so that those portions which are to be intensively inspected are not overlooked.
In the second embodiment, the trace map is projected on the main wing 2, but the present invention is not limited to this example. For example, as shown in
The above embodiments have been described using the main wing 2 of the aircraft 1 as the object, but the present invention is not limited to this example and can also be applied to structural parts of the aircraft 1 other than the main wing 2, or to structures other than the aircraft 1 as well.
Number | Date | Country | Kind |
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2015-40818 | Mar 2015 | JP | national |