Composite structures, forming apparatuses and related systems and methods

1. A method of forming a composite structure having an at least partially annular shape in an at least partially automated process, the method comprising:

supplying at least one ply of material from a material feed assembly to a tool, the at least one ply of material comprising a planar sheet of material containing fibers in at least some matrix material;

orienting a longitudinal axis of the material feed assembly at an oblique angle relative to a longitudinal axis of the tool to produce a varying tension in the at least one ply of material along a lateral direction of the at least one ply of material where the at least one ply of material is stretched over the tool, the tool defining the at least partially annular shape around the longitudinal axis of the tool;

applying the at least one ply of material on a forming surface of the tool configured to form the composite structure having the at least partially annular shape, wherein the fibers in the at least one ply of material are offset relative to a side of the at least one ply of material;

conforming the at least one ply of material to the forming surface of the tool, comprising:

conforming a first portion of the at least one ply of material to a first radius of curvature to the forming surface of the tool;

conforming a middle portion of the at least one ply of material extending between the first portion and a second portion of the at least one ply of material to the forming surface of the tool; and

conforming the second portion of the at least one ply of material to a second radius of curvature to the forming surface of the tool, wherein the second radius of curvature is either greater than or lesser than the first radius of curvature; and

curing the at least one ply of material to form the composite structure.

2. The method of claim 1 , wherein conforming the middle portion of the at least one ply of material comprises extending the middle portion along a portion of the forming surface of the tool that gradually changes from the first radius of curvature to the second radius of curvature.

3. The method of claim 1 , wherein orienting the longitudinal axis of the material feed assembly at the oblique angle relative to the longitudinal axis of the tool comprises orienting a longitudinal axis of a spool of material on the material feed assembly at the oblique angle relative to a centerline of the tool.

4. The method of claim 1 , further comprising positioning a supply of the at least one ply of material on the material feed assembly on one side of the material feed assembly relatively closer to the tool as compared to another opposing side of the supply of the at least one ply of material on the material feed assembly.

5. The method of claim 1 , further comprising forming the composite structure to have an annular shape with a first open end of the annular shape and a second open end of the annular shape.

6. The method of claim 5 , further comprising:

defining the first open end to have a first diameter comprising the first radius of curvature; and

defining the second open end to have a second diameter comprising the second radius of curvature.

7. The method of claim 6 , further comprising forming the middle portion to gradually variate from the first diameter to the second diameter.

8. A method of forming a composite structure having an at least partially annular shape in an at least partially automated process, the method comprising:

supplying at least one ply of material from a material feed assembly to a tool;

as the at least one ply of material is supplied from the material feed assembly to the tool, applying a force to at least a portion of the at least one ply of material comprising:

orienting a longitudinal axis of the material feed assembly at an oblique angle relative to a longitudinal axis of the tool to produce a varying tension in the at least a portion of the at least one ply of material, the varying tension extending from the material feed assembly to the tool;

conforming a first portion of at least one ply of material to a first diameter to a forming surface of the tool;

conforming a second portion of the at least one ply of material to a second diameter to the forming surface of the tool, wherein the second diameter is either greater than or lesser than the first diameter;

extending a middle portion of the at least one ply of material extending between the first portion and the second portion of the at least one ply of material along a portion of the forming surface that gradually changes from the first diameter to the second diameter; and

manipulating the at least one ply of material with a forming mechanism after the at least one ply of material is applied to the tool in order to conform the at least one ply of material to a non-uniform portion of the forming surface of the tool.

9. The method of claim 8 , wherein applying the force to the at least a portion of the at least one ply of material further comprises applying the tension to only a portion of the at least one ply of material between the material feed assembly to the tool.

10. The method of claim 8 , wherein applying the force to the at least a portion of the at least one ply of material further comprises applying relatively more of the tension to a side portion of the at least one ply of material that is stretched over the first diameter than another side portion of the at least one ply of material that is placed over the second diameter.

11. The method of claim 8 , wherein applying the force comprises stretching the at least one ply of material in a direction transverse to a direction of fibers in the at least one ply of material.

12. The method of claim 11 , further comprising pivoting the material feed assembly relative to the tool.

13. The method of claim 12 , further comprising orienting a lateral axis of the material feed assembly at an oblique angle relative to the longitudinal axis of the tool.

14. The method of claim 12 , further comprising supplying the at least one ply of material from a spool of material rotatably coupled to the material feed assembly.

15. The method of claim 12 , further comprising pivoting the material feed assembly relative to the tool to position one side of a spool of material relatively closer to the tool and to position another opposing side of the spool of material relatively further away from the tool.

16. The method of claim 12 , further comprising automatically pivoting the material feed assembly relative and a spool of material relative to the tool during the formation of the composite structure on the tool.

17. A method of forming a composite structure having an annular shape in an at least partially automated process, the method comprising:

supplying at least one ply of material from a material feed assembly to a tool;

conforming a first portion of at least one ply of material to a first diameter to a forming surface of the tool;

conforming a second portion of the at least one ply of material to a second diameter to the forming surface of the tool, wherein the second diameter is or lesser than the first diameter;

as the at least one ply of material is supplied from the material feed assembly to the tool, applying relatively more tension to the first portion of the at least one ply of material that is stretched over the first diameter than the second portion of the at least one ply of material that is stretched over the second diameter by orienting a longitudinal axis of the material feed assembly at an oblique angle relative to a longitudinal axis of the tool, the tension applied to the first portion of the at least one ply of material extending from the material feed assembly to the tool; and

manipulating the at least one ply of material with a forming mechanism after the at least one ply of material is applied to the tool in order to conform the at least one ply of material to a non-uniform portion of the forming surface of the tool.

18. The method of claim 17 , further comprising stretching the at least one ply of material in a direction transverse to a direction of fibers in the at least one ply of material.