Fixture for shape-sensing optical fiber in a kinematic chain

• US 8,616,782 B2
• Filed: 04/24/2012
• Issued: 12/31/2013
• Est. Priority Date: 06/30/2008
• Status: Active Grant

• Current Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Original Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Inventors: Rogers, Theodore W., Prisco, Giuseppe Maria
• Primary Examiner(s): Peng, Charlie
• Assistant Examiner(s): Radkowski, Peter
• Application Number:
  US13/454,282
• Publication Number:
  US 20120266442A1
• Time in Patent Office: 616 Days
• Field of Search: 385/101, 385/66, 606/2
• US Class Current: 385/66
• CPC Class Codes: A61B 2034/2061 using shape-sensors, e.g. fiber shape sensors with Bragg gratings
• CPC Class Codes: A61B 34/30 Surgical robots
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: G01B 11/165 by means of a grating deformed by the object
• CPC Class Codes: G01D 11/245 Housings for sensors
• CPC Class Codes: G01D 5/35303 using a reference fibre, e.g. interferometric devices
• CPC Class Codes: G01D 5/35316 using a Bragg gratings
• CPC Class Codes: G01D 5/35377 Means for amplifying or modifying the measured quantity
• CPC Class Codes: G01M 11/083 by using an optical fiber in contact with the device under test [DUT]
• CPC Class Codes: G02B 6/022 using mechanical stress, e.g. tuning by compression or elongation, special geometrical shapes such as "dog-bone" or taper G02B6/02204 takes precedence; optical modulation using photo-elastic effect G02F1/0131
• CPC Class Codes: G02B 6/3616 Holders, macro size fixtures for mechanically holding or positioning fibres, e.g. on an optical bench supporting carriers of a microbench type G02B6/3648; micromanipulators B25J7/00; cassettes, bobbins G02B6/4439
• CPC Class Codes: G02B 6/3644 the coupling means being through-holes or wall apertures
• CPC Class Codes: G02B 6/38 having fibre to fibre mating means
• CPC Class Codes: Y10T 29/49826 Assembling or joining
• CPC Class Codes: Y10T 29/49838 by stringing
• CPC Class Codes: Y10T 29/49947 by applying separate fastener

Abstract

A first link and a second link are articulated relative to each other via a joint coupled between the first and second links. A shape-sensing optical fiber is used to sense a position of the first link and the second link relative to each other. The fiber passes through a channel having an opening defining a lip and extending from the first link toward the joint. The lip has a curved surface that begins substantially tangent to a wall of the channel, and during bending of the optical fiber, the optical fiber is positioned tangent to the curved surface of the lip.

Claims

1. A method comprising:

articulating a first link and a second link relative to each other via a joint coupled between the first and second links; and

during the articulating, bending a shape-sensing optical fiber to remain tangent along a curved surface of a lip of a channel in the first link through which the fiber extends towards the joint, the curved surface beginning substantially tangent to a wall of the channel.

2. The method of claim 1, further comprising:

during the bending of the optical fiber, distributing a force exerted by the lip along the optical fiber via a tube surrounding the optical fiber.

3. The method of claim 2:

wherein distributing the force exerted by the lip along the optical fiber via a tube surrounding the optical fiber comprises distributing the force exerted by the lip along the optical fiber via a shape memory alloy tube.

4. The method of claim 1 further comprising:

during the bending of the optical fiber, sliding the optical fiber longitudinally relative to the first link.

5. The method of claim 1 further comprising:

during the bending of the optical fiber, fixing an orientation of the optical fiber relative to the first link.

6. The method of claim 1:

wherein articulating the first and second links comprises articulating links in a serial kinematic chain.

7. The method of claim 1:

wherein articulating the first and second links comprises articulating links in a surgical instrument.

8. The method of claim 1:

wherein the optical fiber comprises a length of fiber Bragg gratings positioned adjacent the lip, and further comprising gathering strain information from the length of fiber Bragg gratings during the bending of the optical fiber.

9. The method of claim 8:

wherein bending the shape-sensing optical fiber to remain tangent along the curved surface of the lip reduces localized strain in the length of fiber Bragg gratings positioned adjacent the lip.

10. A method comprising:

articulating a first link and a second link relative to each other via a joint coupled between the first and second links; and

during the articulating, bending a shape-sensing optical fiber as the optical fiber exits a channel in the first link through which the optical fiber extends towards the joint such that a minimum bend radius of the optical fiber is greater than a maximum radius of curvature of a lip of the channel.

11. The method of claim 10:

wherein bending the optical fiber includes following a curved surface of the lip beginning substantially tangent to a wall of the channel.

12. The method of claim 11:

wherein following a curved surface of the lip includes positioning the optical fiber tangent to the curved surface of the lip.

13. The method of claim 10 further comprising:

during the bending of the optical fiber, sliding the optical fiber longitudinally relative to the first link.

14. The method of claim 10 further comprising:

during the bending of the optical fiber, fixing an orientation of the optical fiber relative to the first link.

15. The method of claim 10:

wherein articulating the first and second links comprises articulating links in a serial kinematic chain.

16. The method of claim 10:

wherein articulating the first and second links comprises articulating links in a surgical instrument.

17. The method of claim 10:

wherein the optical fiber comprises a length of fiber Bragg gratings positioned adjacent the lip, and further comprising gathering strain information from the length of fiber Bragg gratings during the bending of the optical fiber.

18. A method of articulating links in a surgical instrument, the method comprising:

articulating a first link and a second link in a surgical instrument relative to each other via a joint coupled between the first and second links; and

during the articulating, bending a shape-sensing optical fiber to remain tangent along a curved surface of a lip of a channel in the first link through which the fiber extends towards the joint, the curved surface beginning substantially tangent to a wall of the channel.

19. The method of claim 18:

wherein articulating the first and second links comprises articulating links in a serial kinematic chain.

20. The method of claim 18:

wherein articulating the first and second links comprises articulating a wrist mechanism relative to an end effector.