Fixture For Shape-Sensing Optical Fiber In A Kinematic Chain

摘要

Localized strain is effectively eliminated in a shape sensing optical fiber where the fiber exits a link in a kinematic chain. In one aspect, the fiber is positioned in a channel within a fiber fixture portion of the link, and a surface of a lip of the channel is curved. The curved surface of the lip begins tangent to a wall of the channel and has a maximum radius of curvature that is less than the minimum bend radius that the fiber will experience during shape sensing. In another aspect, the fiber is positioned within a shape memory alloy tube that extends from the link.

主权项

1. An apparatus comprising:
a first link, a second link, and a joint that couples the first and second links; an optical fiber extending between the first link and the second link, wherein a limit range of motion of the joint defines a minimum bend radius of the optical fiber; and a fixture by which the optical fiber is constrained with reference to the first link, wherein the fixture comprises a channel defined therein in which the fiber is positioned to place a length of fiber containing fiber Bragg gratings adjacent a lip of the channel where the channel opens out of the fixture, wherein a curve of a surface of the lip begins effectively tangent to a wall of the channel, and wherein the radius of curvature of the surface of the lip that substantially intersects a bending plane of the fiber as the joint moves is effectively less than the defined minimum bend radius of the optical fiber.