Abstract
A method of installing a fixture, such as a bracket, in a fuselage structure of an aircraft or spacecraft, includes providing or generating a three-dimensional digital model of the fixture; arranging a head of an additive manufacturing apparatus in, on or adjacent the fuselage structure; and forming the fixture in situ in or on the fuselage structure with the head of the additive manufacturing apparatus based upon the digital model of the fixture. The fixture is installed in or on the fuselage structure by bonding or fusing the fixture to the fuselage structure as the fixture is formed, and the step of forming the fixture in situ includes: forming an anchored portion of the fixture which is non-movably fixed to the structure; and forming an operable portion of the fixture which is movable relative to the anchored portion.
Claims
1. A method of installing a fixture in or on a structure of an aircraft or spacecraft, the method comprising: arranging a head of an additive manufacturing apparatus in, on or adjacent the structure; and forming the fixture in situ on the structure with the head of the apparatus based on a digital model of the fixture, the fixture being installed in or on the structure by connecting the fixture to the structure as the fixture is formed, and forming the fixture in situ comprising: forming an anchored portion of the fixture which is non-movably fixed to the structure; and forming an operable portion of the fixture which is movable relative to the anchored portion.
2. The method of claim 1, wherein forming the fixture in situ comprises building the fixture sequentially.
3. The method of claim 2, wherein building the fixture sequentially comprises generating and building up layers of the fixture on the structure with the head of the apparatus, the layers of the fixture being sequentially deposited on the structure.
4. The method of claim 1, wherein connecting the fixture to the structure includes at least one of: bonding or fusing one or more layers of the fixture to the structure as the layers are generated; and forming the fixture in situ in a mechanical fit or a mechanical engagement with part of the structure.
5. The method of claim 4, wherein bonding of the fixture to the structure includes depositing one or more layer or region of adhesive on the structure, wherein the one or more layer or region of adhesive is deposited at least in a region of the anchored portion of the fixture.
6. The method of claim 5, wherein depositing one or more layer or region of adhesive on the structure is performed before generating and building up layers of the fixture on the structure.
7. The method of claim 1, wherein the anchored portion of the fixture forms a holder for supporting one or more elements of a system to be mounted on the structure, wherein the operable portion of the fixture forms a fastener for securing the element(s) to the holder.
8. The method of claim 7, wherein the operable portion is movable and configured to wrap around or encompass the one or more elements in the manner of a strap or tie.
9. The method of claim 1, wherein the operable portion is formed locally attached to the structure and is separable for movement relative to the anchored portion.
10. The method of claim 9, wherein the operable portion is separable by peeling or breaking the local attachment.
11. The method of claim 1, wherein the three-dimensional digital model of the fixture includes data on a desired position of the fixture within structure, wherein the step of forming the fixture in situ includes positioning the head of the additive manufacturing apparatus in or adjacent the structure based upon the digital model.
12. The method of claim 11, wherein the structure includes reference markers for spatial correlation to reference points in the digital model of the fixture.
13. A fixture generated in situ in or on a structure of an aircraft or spacecraft based on a three-dimensional digital model, wherein the fixture is connected to the structure as the fixture is formed, and wherein the fixture comprises an anchored portion which is non-movably fixed to the structure and an operable portion which is movable relative to the anchored portion.
14. The fixture of claim 13 , wherein the anchored portion of the fixture comprises a holder for supporting one or more elements or items of a system to be mounted on the structure, and the operable portion of the fixture comprises a fastener for securing the one or more elements or items to the holder.
15. The fixture of claim 13, wherein the operable portion comprises a strap or tie to secure one or more elements of a system to be mounted on the structure to the fixture.
16. The fixture of claim 13, wherein the fixture comprises sequentially generated or deposited layers which are bonded or fused to the fuselage structure.
17. The fixture of claim 13, wherein the operable portion has a local attachment to the structure, wherein the local attachment is separable from the structure for moving the operable portion relative to the anchored portion.
18. The fixture of claim 13, wherein the fixture is formed from a polymer material or a metal.
19. The fixture of claim 18, wherein the polymer material comprises one or more of acrylonitrile butadiene styrene, high density polyethylene, an eutectic metal, and one or more metal powders.
20. The fixture of claim 13, wherein the fixture is bonded or fused to the structure.
21. An aircraft or spacecraft, having a body structure with one or more fixtures, each of the fixtures being generated in situ in or on a structure of an aircraft or spacecraft based on a three-dimensional digital model, wherein the fixture is connected to the structure as the fixture is formed, and wherein the fixture comprises an anchored portion which is non-movably fixed to the structure and an operable portion which is movable relative to the anchored portion.
22. The aircraft or spacecraft of claim 21, wherein the fixture is bonded or fused to the structure.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0045] For a more complete understanding of the present disclosure and the advantages thereof, exemplary embodiments of the disclosure herein are explained in more detail in the following description with reference to the accompanying drawings, in which like reference characters designate like parts and in which:
[0046] FIG. 1 is a schematic side view of a section of a fuselage or hull structure of an aircraft, upon which a fixture or bracket is being installed according to an embodiment of the disclosure herein;
[0047] FIG. 2 shows four schematic side views (a) to (d) of the fuselage or hull structure in FIG. 1, upon which the fixture or bracket is being installed according to an embodiment of the disclosure herein;
[0048] FIG. 3 schematically shows three stages (i) to (iii) of a method or technique of installing the fixture or bracket according to a particular embodiment;
[0049] FIG. 4 is a schematic perspective view of a fixture or a bracket according to an embodiment of the disclosure herein;
[0050] FIG. 5a shows a schematic perspective view of a fixture or bracket according to an embodiment with the fixture or bracket installed and in operation on a fuselage or hull structure;
[0051] FIG. 5b shows a schematic perspective view of a fixture or bracket according to an embodiment with the fixture or bracket installed and in operation on a fuselage or hull structure;
[0052] FIG. 6 is a schematic partially cross-sectional view of a head of an additive manufacturing apparatus on a robot arm for installing a fixture according to an embodiment of the disclosure herein;
[0053] FIG. 7 is a schematic side view of a nozzle on the head of an additive manufacturing apparatus according to an embodiment of the disclosure herein;
[0054] FIG. 8 shows two schematic perspective views (a) and (b) of the nozzle in FIG. 7;
[0055] FIG. 9a shows a schematic perspective view of a head of an additive manufacturing apparatus on a robot arm for installing a fixture according to an embodiment of the disclosure herein;
[0056] FIG. 9b is a schematic side view of the head of an additive manufacturing apparatus in FIG. 9a;
[0057] FIG. 10 is a flow diagram which schematically illustrates a method according to a preferred embodiment;
[0058] FIG. 11 is a schematic illustration of an aircraft in which one or more brackets according to an embodiment of the disclosure herein are installed; and
[0059] FIG. 12 is a schematic view of a space station upon which a fixture or element is being installed according to an embodiment of the disclosure herein.
DETAILED DESCRIPTION
[0060] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate particular embodiments of the disclosure herein and together with the description serve to explain the principles of the disclosure herein. Other embodiments of the disclosure herein and many of the attendant advantages of the disclosure herein will be readily appreciated as they become better understood with reference to the following detailed description.
[0061] It will be appreciated that common and well understood elements that may be useful or necessary in a commercially feasible embodiment are not necessarily depicted in order to facilitate a more abstracted view of the embodiments. The elements of the drawings are not necessarily illustrated to scale relative to each other. It will further be appreciated that certain actions and/or steps in an embodiment of a method may be described or depicted in a particular order of occurrences while those skilled in the art will understand that such specificity with respect to sequence is not necessarily required. It will also be understood that the terms and expressions used in the present specification have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study, except where specific meanings have otherwise been set forth herein.
[0062] With reference firstly to FIG. 1 of the drawings, a system for installing a fixture 1 (here in the form of a bracket) on an airframe or fuselage structure F of an aircraft according to a method of the disclosure herein is illustrated schematically. The airframe or fuselage structure F of the aircraft in this embodiment comprises a curved shell section of the fuselage, comprised of a carbon-fiber reinforced polymer composite, which is supported in this case by brace elements B extending horizontally from a vertically extending supporting framework S. Also shown in FIG. 1 is a robot assembly 2, which includes a robotic arm 3 having a plurality of articulated joints 4, each of which is drivable in at least one and preferably in a number of degrees-of-freedom. The robot assembly 2 is itself mounted for translational movement along a rail member 5 in a direction perpendicular to a plane of drawing FIG. 1.
[0063] Mounted on a distal end region of the robot arm 3 is a head 6 of an additive manufacturing apparatus 7, which is generally understood or may be referred to as a 3D printer device. This additive manufacturing apparatus 7 may operate on any one of the known 3D printing techniques, such as fused deposition modelling (FDM), laser sintering (LS), or stereo-lithography (SLA). Particularly preferred in this embodiment is a fused deposition modelling (FDM) apparatus 7. The movement of the robotic assembly 2, and more particularly of the robot arm 3 via the articulated joints 4 and its position along the rail member 5, are computer-controlled via a computer processor P (illustrated schematically here, and shown later in FIG. 3), which also controls operation of the additive manufacturing apparatus 7. To commence the installation of a new fixture or bracket 1 according to the inventive method, the head 6 of the apparatus 7 is moved by the robot arm 3 in the direction of the arrow in FIG. 1 to a predetermined position Z on the fuselage shell F.
[0064] Referring now also to FIGS. 2(a) to 2(d) of the drawings, the steps of forming or building the fixture or bracket 1 in the fuselage structure F is illustrated in the series of four images (a) to (d). In the image of FIG. 2(a), the head 6 of the FDM apparatus 7 arranged at the distal end region of the robotic arm 3 has been moved into proximity with a surface of the fuselage structure F of the aircraft at the position Z. A three-dimensional digital model M of the fixture or bracket 1 is provided or generated in the computer processor P and, based upon the data in this digital model M of the bracket 1, the computer processor P then controls the head 6 of the FDM apparatus 7 to deposit layers of polymer material onto the CFRP fuselage structure as the head 6 of the apparatus 7 is moved along the surface of shell structure F in the direction of the arrow in FIG. 2(a). Then, in FIG. 2(b), one or more layers L1 of the bracket 1 has/have been deposited upon the fuselage structure F at the predetermined position Z, which layer(s) is/are bonded or fused to CFRP structure F.
[0065] The head 6 of the FDM apparatus 7 is then moved slightly away from the fuselage structure F in the direction of the arrow shown in FIG. 2(b). As shown in FIG. 2(c), the head 6 may then commence deposition of one or more new layers L2 of the polymer material, which builds upon the previous layers L1 and thus builds-up the three-dimensional shape or form of the fixture or bracket 1. This procedure continues with reference to FIG. 2(d) of the drawings until the final 3D shape of the bracket 1 has been completed.
[0066] With reference also now to FIG. 3 of the drawings, the method according to this preferred embodiment of the disclosure herein is illustrated in the three stages (i) to (iii). For example, in FIG. 3(i) an operator O is shown at a work-station W of the computer processor P engaged in the task of providing and/or generating the three-dimensional (3D) digital model M of the fixture or bracket 1 to be installed according to the method of this embodiment. The computer processor P at which the operator O is working is also responsible for the computer-controlled operation of the robot assembly 2 and the additive manufacturing apparatus 7 described above with respect to FIGS. 1 and 2.
[0067] FIG. 3(ii) schematically illustrates the step of positioning the robot assembly 2 with respect to the fuselage structure F upon which the bracket 1 is to be formed and installed. In this regard, the robot assembly 2 is movable on one or more rails 5 within the tubular fuselage structure F, preferably on one of a plurality of separate rails 5, e.g., at separate heights or separate floors in the fuselage F. In this regard, the fuselage structure F may be a tubular shell as seen in FIG. 3(ii), rather than just a shell section shown in FIG. 1. Also, the robot assembly 2 may include a plurality of robotic arms 3 for simultaneously operating at various different positions Z within the fuselage structure F, i.e. in order to simultaneously build and install a plurality of fixtures or brackets 1 at different positions.
[0068] With regard to the positioning of the robotic assembly 2, the digital model M of the fixture or bracket 1 may include data concerning a specific desired or predetermined position Z of a particular bracket 1 on the fuselage structure F. This data can then be used together with reference markers R provided on the fuselage structure F, which are preferably detectable and identifiable by sensors (not shown) provided on the robot assembly 2 to give spatial correlation for moving the robotic arm 3 relative to the fuselage structure F, and particularly the head 6 of the additive manufacturing apparatus 7, to the correct position Z for forming and installing that particular bracket 1 based upon the data in the digital model M.
[0069] FIG. 3(iii) essentially corresponds to FIG. 2 of the drawings and schematically illustrates the sequential deposition or layer build-up and installation of a particular bracket 1 at the desired or predetermined position Z within the fuselage structure F, with the bracket 1 being simultaneously bonded or fused to the material of the fuselage structure F.
[0070] Referring to FIG. 4 of the drawings, an example of a fixture or bracket 1 installed via the method shown in FIGS. 2(a) to 2(d) and in FIG. 3(iii) is illustrated in a perspective view. The fixture or bracket 1 comprises an anchored portion 8 in the form of a wedge or block that is non-movably fixed to the fuselage F. In addition, the fixture or bracket 1 comprises an operable portion 9 which is configured to move relative to the anchored portion 8. In particular, it will be noted that the anchored portion 8 of the bracket 1 comprises a curved holder 10 for supporting elements or items D, such as cables or conduits, of an electrical system to be mounted on the structure F. The operable portion 9 of the bracket 1, on the other hand, comprises a strap or tie 11 to secure the cables or conduits D to the bracket. In this regard, the bracket 1 includes a binder or fastener 12 for binding or fastening the strap 11 with respect to the anchored portion 8 in order to securely hold or retain the cables or conduits D in the desired position within the holder 10. To this end, the binder or fastener 12 for binding or fastening comprises holes 13 formed in the strap 11, which are configured to cooperate with a slot 14 and pin 15 formed on the wedge- or block-shaped anchored portion 8. In this respect, FIGS. 5a and 5b of the drawings illustrate slightly modified embodiments of the fixture or bracket 1 compared to FIG. 4 but nevertheless illustrate the general principles of its use or operation.
[0071] In this context, it will be noted that the operable portion 9 comprising the strap or tie 11 may be installed with a local attachment 16 via a weak fusing or bonding to the structure F. Thus, this local attachment of the operable portion 8 may be severable, for example by peeling the strap or tie 11 from the structure F to move the operable portion 9 relative to the anchored portion 8. In an initially installed state (e.g. shown by the broken lines in FIG. 5a) therefore, the operable portion 9 of the bracket 1 may be in an inoperative position. After the strap or tie 11 has been wrapped over or around the cables or conduits D on the holder 10 of the bracket 1 and passed through the slot 14 such that one of the holes 13 may receive and engage the pin 15 to securely fasten the cables or conduits D on the bracket 1, as shown in FIG. 5b, any excess length at a projecting free end of the strap or tie 11 may optionally be cut off to shorten that projecting end.
[0072] In the method of installing a fixture or bracket 1 according to this disclosure herein, the anchored portion 8 of the bracket 1 is non-movably fixed (i.e. anchored) to the structure F. This may involve forming this anchored portion 8 of the bracket 1 in a mechanical fit or a mechanical engagement or connection with part of the fuselage structure F. However, it may also involve the anchored portion 8 of the bracket 1 being bonded to the structure F as it is generated and/or deposited on the structure. Thus, the step of bonding the anchored portion 8 to the structure F preferably includes depositing one or more layers or regions of adhesive filament G (e.g., lines of glue or adhesive filament G, as in FIG. 4) to which the bracket 1 is to be connected. In this regard, depositing the one or more layers or regions of adhesive filament G occurs before generating or building up layers L1, L2 of the bracket, and especially the anchored portion 8, on the structure. To this end, the applied layer(s) or region(s) of adhesive filament correspond at least to a region of the anchored portion 8 of the bracket, and desirably solely to a region of the anchored portion 8 of the bracket 1. In this way, the adhesive acts to ensure that the anchored portion 8 is non-movably fixed to the structure F.
[0073] With reference to drawings FIGS. 6 to 8, details of a head 6 of an additive manufacturing apparatus 7 mounted on a robot arm 3 of a robot assembly 2 for forming and/or installing a fixture, such as a bracket 1, in or on a fuselage structure F of an aircraft are shown schematically. As noted above, the head 6 is configured for building the bracket 1 sequentially, especially by building up layers L1, L2 of filling filament on the structure F. To this end, the head 6 includes a nozzle portion 17 for dispensing and applying the layers L1, L2 of filling filament material to generate or build up the bracket 1 on the fuselage F. The filling material is supplied to the nozzle portion 17 via supply line 18 after it has been pre-heated to a desired operating temperature. The head 6 of the apparatus 7 further includes a number of sensors 19, such as distance sensors or contact sensors, to measure or detect a position or spacing of the nozzle portion 17 with respect to a surface of the structure F on which the bracket 1 is to be formed, and a position adjustment mechanism 20 to provide high level positioning accuracy of the apparatus head 6 (e.g. 3D printer head) which is generally important for fineness of layers L1, L2. In this regard, the sensors 19 provide data to a control unit in the processor P to control operation of the position adjustment mechanism 20. The position adjustment mechanism 20 in turn includes threaded rods 21, which may be driven by the control unit to finely adjust a spacing of the nozzle portion 17 with respect to the surface of the fuselage structure F. The position adjustment mechanism 20 may also be drivable to displace the nozzle portion 17 laterally across the surface, as denoted by the arrows in FIG. 6.
[0074] Where the method of installing the bracket 1 involves bonding the anchored portion 8 to the structure F by depositing a layer or region of adhesive filament before the layers L1, L2 of the bracket 1, especially of the anchored portion 8, are generated and built up on the structure, it is particularly desirable that the nozzle portion 17 of the apparatus head 6 is configured as shown in FIGS. 7 and 8. In this embodiment, the nozzle portion 17 is configured with two separate nozzle outlets 22, one of which is adapted to dispense and/or apply the adhesive filament and the other of which is adapted to dispense and/or apply the filling material of the bracket 1. In this way, one nozzle portion 17 can operate for applying both adhesive and then the filling material to generate the bracket 1. The separate nozzle outlets 22 are designed with different dimensions to suit the different materials and may also operate at different temperatures to suit the properties of the adhesive and the filling material, respectively. This concept of a single apparatus head 6 with dual nozzle outlets 22 optimizes use of the bonding adhesive in a fast production process.
[0075] Referring now to drawing FIGS. 9a and 9b, an embodiment of an articulated apparatus head 6 is shown, which is especially practical when the fixture or bracket 1 is to be mechanically connected to the structure F, e.g. via one or more holes or apertures through a structural member. That is, by forming the fixture or bracket 1 in mechanical connection with a hole or aperture of a structural member, the form of the bracket 1 may fix the bracket without using adhesive. In such cases, a highly manoeuvrable head 6 is desirable to enable the head 6 to approach an installation position Z from various angles. To this end, the head 6 of the apparatus 7 in this embodiment is articulated to pivot or rotate about two pivot joints 23, 24 respectively defining two perpendicular axes y, z. In this way, the head of the ALM apparatus 7 provided on the robotic arm 3 is highly manoeuvrable to assist installation of the bracket 1 in confined spaces and/or when the bracket 1 is to be formed from both sides of a structural member.
[0076] Referring now to FIG. 10 of the drawings, a flow diagram is shown that again schematically illustrates the steps in the method of the preferred embodiment. In this regard, the first box I of FIG. 10 represents the step of providing or the step of generating a three-dimensional (3D) digital model M of the bracket 1, which digital model M is then made available to the computer processor P that operates and controls the robot assembly 2 carrying the additive manufacturing device 7. The second box II then represents the step of moving the head 6 of the additive manufacturing apparatus 7 to a predetermined position Z in the fuselage structure F based on position data in the digital model M and, in this embodiment, depositing one or more layers or regions of adhesive G for bonding the bracket 1 to be formed to the structure F. The third box III represents the step of forming the bracket 1 in situ in the fuselage structure F with the head 6 of the FDM apparatus 7 by sequentially building up the bracket 1 in layers based upon the digital model M of the bracket in the computer processor P. This step includes forming an anchored portion 8 of the bracket 1 which is non-movably fixed to the structure, and forming an operable portion 9 of the bracket 1, such as a strap or tie 11 which is movable relative to the anchored portion 8. The final box IV in drawing FIG. 10 represents the step of connecting the bracket 1 by bonding or fusing at least anchored portion 8 to the CFRP fuselage structure F via the adhesive G, as or when the bracket 1 is formed.
[0077] Following the above description of the method and the fixture or bracket 1 itself as well as the ALM apparatus, FIG. 11 of the drawings now schematically illustrates an aircraft A that incorporates a fuselage structure F, in which at least one fixture or bracket 1, and preferably a plurality thereof, has or have been installed according to a method of the present disclosure.
[0078] With reference to FIG. 12 of the drawings, on the other hand, an alternative embodiment is now illustrated schematically. In this embodiment, the inventive method is being carried out on a space station T which is currently in orbit. The space station T includes solar collector modules C, modules H for human occupation, and an antenna module I, all of which are interconnected by a structural framework X. In this example, the method is employed to conduct a repair to a part on the antenna module I. Again, a robot assembly 2, which includes a robotic arm 3 having remotely controlled articulated joints 4 is employed, which avoids the need for an astronaut to under-take a space-walk. The structural framework X may include one or more rails 5 for guiding movement of the robot 2 to the antenna module I. Also, a head 6 of an additive manufacturing apparatus 7 or 3D printer device is mounted at an end region of the robotic arm 3. In this way, the method described above with reference to FIGS. 1-9 can be performed with the robot assembly 2 on the space station T to generate and install a new element or fixture 1 to repair the antenna module I. In the event that no rails 5 are available for the robot 2 on the structural framework X, it will be noted that the head 6 of the additive manufacturing apparatus 7 may also be used to generate and install rail members 5 on the framework X of the space station T according to the method of the disclosure herein for guiding the robotic assembly 2 to that part of the antenna module I to be repaired.
[0079] Although specific embodiments of the disclosure herein have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations exist. It should be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. Generally, this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.
[0080] In this document, the terms “comprise”, “comprising”, “include”, “including”, “contain”, “containing”, “have”, “having”, and any variations thereof, are intended to be understood in an inclusive (i.e. non-exclusive) sense, such that the process, method, device, apparatus or system described herein is not limited to those features or parts or elements or steps recited but may include other elements, features, parts or steps not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, the terms “a” and “an” used herein are intended to be understood as meaning one or more unless explicitly stated otherwise. Moreover, the terms “first”, “second”, “third”, etc. are used merely as labels, and are not intended to impose numerical requirements on or to establish a certain ranking of importance of their objects.
[0081] While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.
