Insertion tool

1. A tool for inserting into a cavity, the tool comprising:

a plurality of segments moveably coupled to one another, each segment moveable relative to an adjacent segment between a bent position and a coupled position, the plurality of segments comprising a first segment, the first segment comprising:

a core formed of a first material;

a shell formed of a second material and comprising a guide feature, a drive feature, a line guide, or a combination thereof;

wherein the first material defines a greater stiffness than the second material;

wherein the guide feature includes a dedicated bearing surface on the shell;

wherein the drive feature includes a repeating surface profile on the shell; and

wherein a tension line extends through the line guide to continuously bias the first segment toward the coupled position with an adjacent segment of the plurality of segments.

2. The tool of claim 1 , wherein the core of the first segment is configured to abut a core of a forward adjacent segment and a core of an aft-adjacent segment.

3. The tool of claim 1 , wherein the repeating surface profile is a plurality of gear teeth.

4. The tool of claim 1 , wherein the first segment defines a local longitudinal direction, a first end, and a second end, and wherein the line guide extends substantially from the first end to the second end along the local longitudinal direction.

5. The tool of claim 1 , wherein the tension line is configured to hold the plurality of segments in the coupled position, and wherein the tension line is formed of a line material defining a line material hardness greater than a second material hardness of the second material.

6. The tool of claim 1 , wherein the first material is a metal material, a ceramic material, or a combination thereof, and wherein the second material is a polymer material.

7. The tool of claim 1 , wherein the first material defines a first material stiffness, wherein the second material defines a second material stiffness, and wherein the first material stiffness is at least five times greater than the second material stiffness.

8. The tool of claim 1 , wherein the tool is configured as an insertion tool, and wherein the cavity is an annular cavity of a gas turbine engine.

9. The tool of claim 1 , wherein the shell of the first segment is overmolded onto the core, and wherein the shell of the first segment substantially covers an entirety of an exterior of the core.

10. A tool for inserting into a cavity, the tool comprising:

a plurality of segments moveably coupled to one another, each segment moveable relative to an adjacent segment between a bent position and a coupled position, the plurality of segments comprising a first segment, the first segment comprising:

a core formed of a first material;

a shell formed of a second material and comprising or defining a guide feature, a drive feature, a line guide, or a combination thereof;

wherein the first material defines a greater stiffness than the second material; and

wherein the shell comprises the guide feature, and wherein the guide feature is a segment bearing feature.

11. The tool of claim 10 , wherein the first material defines a first coefficient of friction, wherein the second material defines a second coefficient of friction, and wherein the first coefficient of friction is at least about fifteen percent greater than the second coefficient of friction.

12. The tool of claim 10 , wherein the segment bearing feature is a segment sliding bearing feature, and wherein the tool further comprises:

an insertion tube comprising a tube sliding plain bearing feature configured to interact with the segment sliding bearing feature, wherein the tube sliding plain bearing feature is formed of a third material defining a third material hardness greater than a second material hardness of the second material.

13. A gas turbine engine comprising:

a component defining an opening to a cavity within the gas turbine engine; and

an insertion tool extending through the opening defined by the component into the cavity, the insertion tool comprising:

a plurality of segments moveably coupled to one another, each segment moveable relative to an adjacent segment between a bent position and a coupled position, the plurality of segments comprising a first segment, the first segment comprising a core formed of a first material, and a shell formed of a second material and comprising or defining a guide feature, a drive feature, a line guide, or a combination thereof, wherein the first material defines a greater stiffness than the second material, wherein the core of the first segment is configured to abut a core of a forward adjacent segment and a core of an aft-adjacent segment.

14. The gas turbine engine of claim 13 , wherein the cavity is an annular cavity of the gas turbine engine.

15. The gas turbine engine of claim 13 , wherein the shell comprises the drive feature, wherein the drive feature is a plurality of gear teeth.

16. The gas turbine engine of claim 13 , wherein the shell comprises the guide feature, and wherein the guide feature is a segment sliding plain bearing feature.

17. The gas turbine engine of claim 16 , wherein the first material defines a first coefficient of friction, wherein the second material defines a second coefficient of friction, and wherein the first coefficient of friction is at least about fifteen percent greater than the second coefficient of friction.

18. The gas turbine engine of claim 13 , wherein the shell comprises the line guide.

19. The gas turbine engine of claim 13 , wherein the drive feature includes a repeating surface profile on the shell.

20. The gas turbine engine of claim 13 wherein a tension line extends through the line guide to hold the first segment in the coupled position with an adjacent segment of the plurality of segments.