FIBER OPTIC INSTRUMENT SHAPE SENSING SYSTEM AND METHOD
An instrument system that includes an elongate body, a first optical fiber, a second optical fiber, and a controller is provided. The first optical fiber is operatively coupled to the elongate body and has a first strain sensor provided on the first optical fiber. The second optical fiber is not directly coupled to the elongate body and has a second strain sensor provided on the second optical fiber. The controller is operatively coupled to the first optical fiber and to the second optical fiber. The controller is adapted to receive a first signal from the first strain sensor and to receive a second signal from the second strain sensor. The first optical fiber has a different size than the second optical fiber.
1 . An instrument system, comprising:
an elongate body;
a first optical fiber operatively coupled to the elongate body and having a first strain sensor provided on the first optical fiber;
a second optical fiber that is not directly coupled to the elongate body and that has a second strain sensor provided on the second optical fiber; and
a controller operatively coupled to the first optical fiber and to the second optical fiber and adapted to receive a first signal from the first strain sensor and to receive a second signal from the second strain sensor,
wherein the first optical fiber has a different size than the second optical fiber.
2 . The instrument system of claim 1 , wherein the elongate body is adapted to be located inside a patient and wherein the second optical fiber is located outside the patient, wherein the second optical fiber is bigger than the first optical fiber.
3 . The instrument system of claim 2 , wherein a diameter of the second optical fiber is at least twice a diameter of the first optical fiber.
4 . The instrument system of claim 2 , wherein the first optical fiber comprises a plurality of optical fiber cores and the second optical fiber comprises a plurality of optical fiber cores, wherein the plurality of optical fiber cores of the second optical fiber are spread further apart than the plurality of optical fiber cores of the first optical fiber.
5 . The instrument system of claim 1 , further comprising an actuation element adapted to actuate the elongate body, wherein the second optical fiber is operatively coupled to the actuation element.
6 . The instrument system of claim 5 , wherein the controller is adapted to determine, based on the first signal, a position of the actuation element and is adapted to determine, based on the second signal, a position of the elongate body relative to the position of the actuation element.
7 . A method for tracking an elongate body, comprising:
receiving a first signal from a first strain sensor provided on a first optical fiber operatively coupled to an elongate body; and
receiving a second signal from a second strain sensor provided on a second optical fiber that is not directly coupled to the elongate body, wherein the first optical fiber has a different size than the second optical fiber.
8 . The method of claim 7 , wherein the receiving the first signal from the first strain sensor provided on the first optical fiber comprises receiving a signal from an optical fiber located inside a patient, and wherein the receiving the second signal from the second strain sensor provided on the second optical fiber comprises receiving a signal from an optical fiber located outside the patient.
9 . The method of claim 8 , wherein a diameter of the second optical fiber is at least twice a diameter of the first optical fiber.
10 . The method of claim 8 , wherein the first optical fiber comprises a plurality of optical fiber cores and the second optical fiber comprises a second plurality of optical fiber cores, wherein the plurality of optical fiber cores of the second optical fiber are spread further apart than the plurality of optical fiber cores of the first optical fiber.
11 . The method of claim 7 , wherein the receiving the second signal from the second strain sensor provided on the second optical fiber comprises receiving a signal from an optical fiber operatively coupled to an actuation element adapted to actuate the elongate body.
12 . The method of claim 11 , further comprising:
determining, based on the first signal, a position of the actuation element; and
determining, based on the second signal, a position of the elongate body relative to the position of the actuation element.