Additive manufactured aircraft structure with reinforcements and method of making the same
In accordance with one embodiment of the present disclosure, an additive manufactured airframe structure is described. This airframe structure can include a plurality of additive manufactured airframe segments coupled together along a longitudinal axis of the airframe structure. Each airframe segment can be monolithic and include an outer wall extending from a first end to a second end along the longitudinal axis. A coupling-element receiving channel can extend through the outer wall generally parallel to the longitudinal axis from a first coupling-channel opening at the first end to a second coupling-channel opening at the second end. A torsion-element receiving channel can also extend through the outer wall at a nonzero angle to the longitudinal axis from a first torsion-channel opening at the first end. A torsion reinforcement element can be received within the torsion-element receiving channel of each additive manufactured airframe segment.
1. A method of assembling an additive manufactured airframe structure, comprising:
inserting, into a torsion-element receiving channel of each of a plurality of segments of an airframe structure, a torsion reinforcement element, wherein the torsion-element receiving channel extends within an outer wall of the segment at a nonzero angle to a longitudinal axis of the segment, wherein the torsion-element receiving channel extends from a first torsion-channel opening at a first end of the outer wall to a second torsion-channel opening at a second end of the outer wall, and wherein the torsion-element receiving channel includes one or more grooves formed along a length of the torsion-element receiving channel;
aligning the plurality of segments along the longitudinal axis such that coupling-element receiving channels formed within the outer wall of each segment are aligned, wherein the coupling-element receiving channels extend parallel to the longitudinal axis;
inserting a coupling reinforcement element through the aligned coupling-element receiving channels to assemble the additive manufactured airframe structure; and
applying an adhesive to an outer surface of the torsion reinforcement element, including applying a pressure differential between the first torsion-channel opening and the second torsion-channel opening, wherein applying the pressure differential includes distributing the adhesive along the grooves to the outer surface of the torsion reinforcement element, and wherein the pressure differential distributes the adhesive along the outer surface of the torsion reinforcement element.
2. The method of claim 1 , further comprising printing, using an additive manufacturing process, the plurality of segments of the airframe structure.
3. The method of claim 1 , further comprising inserting a tab between the torsion reinforcement element and the coupling reinforcement element.
4. The method of claim 1 , further comprising applying an adhesive to an outer surface of the torsion reinforcement element.
5. The method of claim 4 , wherein the step of applying the adhesive is performed after the step of inserting the coupling reinforcement element through the aligned coupling-element receiving channels.
6. The method of claim 5 , wherein the aligned coupling-element receiving channels extend in fluid communication from a first opening at a first end of the aligned plurality of segments to a second opening at a second end of the aligned plurality of segments, wherein applying the adhesive to the outer surface of the coupling reinforcement element includes applying a pressure differential between the first opening and the second opening, and wherein the pressure differential distributes the adhesive along the outer surface of the coupling reinforcement element.
7. The method of claim 1 , wherein inserting the torsion reinforcement element includes inserting the torsion reinforcement element through the first torsion-channel opening, wherein inserting the coupling reinforcement element includes inserting the coupling reinforcement element through a first coupling-channel opening at the first end of the outer wall of each segment, and wherein the first torsion-channel opening is in fluid communication with the first coupling-channel opening.
8. The method of claim 1 , wherein inserting the torsion reinforcement element includes inserting the torsion reinforcement element through the first torsion-channel opening, wherein inserting the coupling reinforcement element includes inserting the coupling reinforcement element through a first coupling-channel opening at the first end of the outer wall of each segment, and wherein the first torsion-channel opening is spaced apart from the first coupling-channel opening at the first end of the outer wall.
9. The method of claim 1 , wherein aligning the plurality of segments along the longitudinal axis also includes aligning second coupling-element receiving channels formed within the outer wall of each segment, wherein the second coupling-element receiving channels extend parallel to the longitudinal axis, and wherein the method further comprises inserting a second coupling reinforcement element through the aligned second coupling-element receiving channels.
10. The method of claim 9 , wherein inserting the torsion reinforcement element includes inserting the torsion reinforcement element between the coupling-element receiving channel and the second coupling-element receiving channel.
11. The method of claim 1 , wherein inserting the torsion reinforcement element into each of the segments includes arranging the torsion reinforcement element in each of the segments into a spiral pattern along the longitudinal axis.
12. The method of claim 1 , wherein inserting the torsion reinforcement element includes:
inserting the torsion reinforcement element into the torsion-element receiving channel of a first of the segments at the nonzero angle having a first sign; and
inserting the torsion reinforcement element into the torsion-element receiving channel of a second of the segments at the nonzero angle having a second sign opposite to the first sign.
13. The method of claim 1 , wherein inserting the torsion reinforcement element into each segment includes inserting the torsion reinforcement element through the first torsion-channel opening, and wherein the method further comprises inserting, through a second torsion-channel opening at a second end of the outer wall of each segment and into a second torsion-element receiving channel of each of the segments, a second torsion reinforcement element.
14. A method of assembling an additive manufactured airframe structure, comprising:
inserting, into a torsion-element receiving channel of each of a plurality of segments of an airframe structure, a torsion reinforcement element, wherein the torsion-element receiving channel extends within an outer wall of the segment at a nonzero angle to a longitudinal axis of the segment;
aligning the plurality of segments along the longitudinal axis such that coupling-element receiving channels formed within the outer wall of each segment are aligned, wherein the coupling-element receiving channels extend parallel to the longitudinal axis, and wherein the aligned coupling-element receiving channels extend in fluid communication from a first opening at a first end of the aligned plurality of segments to a second opening at a second end of the aligned plurality of segments;
inserting a coupling reinforcement element through the aligned coupling-element receiving channels to assemble the additive manufactured airframe structure; and
applying, after the step of inserting the coupling reinforcement element through the aligned coupling-element receiving channels, an adhesive to an outer surface of the coupling reinforcement element, including applying a pressure differential between the first opening and the second opening, wherein the coupling-element receiving channels include one or more grooves formed along a length of the coupling-element receiving channels, wherein applying the pressure differential includes distributing the adhesive along the grooves to the outer surface of the coupling reinforcement element, and wherein the pressure differential distributes the adhesive along the outer surface of the coupling reinforcement element.
15. The method of claim 14 , further comprising applying an adhesive to an outer surface of the torsion reinforcement element.
16. The method of claim 15 , wherein the step of applying the adhesive to the outer surface of the torsion reinforcement element is performed after the torsion reinforcement element is inserted through the torsion-element receiving channel.
17. The method of claim 15 , wherein the torsion-element receiving channel extends from a first torsion-channel opening at a first end of the outer wall to a second torsion-channel opening at a second end of the outer wall, wherein applying the adhesive to the outer surface of the torsion reinforcement element includes applying a pressure differential between the first torsion-channel opening and the second torsion-channel opening, and wherein the pressure differential distributes the adhesive along the outer surface of the torsion reinforcement element.