Fiber optic shape sensor

• US 8,358,883 B2
• Filed: 02/06/2012
• Issued: 01/22/2013
• 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: Prisco, Giuseppe Maria
• Primary Examiner(s): PENG, CHARLIE YU
• Application Number:
  US13/366,534
• Publication Number:
  US 20120132009A1
• Time in Patent Office: 351 Days
• Field of Search: 385/12, 385/13
• US Class Current: 385/12
• CPC Class Codes: A61B 1/009 with bending or curvature detection of the insertion part
• CPC Class Codes: A61B 2034/2061 using shape-sensors, e.g. fiber shape sensors with Bragg gratings
• CPC Class Codes: A61B 2090/061 for measuring dimensions, e.g. length
• CPC Class Codes: A61B 34/30 Surgical robots
• CPC Class Codes: A61B 34/35 for telesurgery
• CPC Class Codes: G01L 1/246 using integrated gratings, e.g. Bragg gratings
• CPC Class Codes: G02B 6/02042 Multicore optical fibres
• CPC Class Codes: Y10T 74/20305 Robotic arm

Abstract

A shape sensing system to determine the position and orientation of one link with respect to another link in a kinematic chain. An optical fiber is coupled to two or more links in a kinematic chain. A shape sensing segment is defined to start at a proximal link and to end at a distal link, crossing one or more joints. A reference frame is defined at the start of the shape sensing segment. As the joints move, an interrogator senses strain in the shape sensing segment. The sensed strain is used to output a Cartesian position and orientation of the end of the shape sensing segment with respect to the reference frame defined at the start of the shape sensing segment. The pose of the kinematic chain is determined from the Cartesian positions and orientations of one or more shape sensing segments defined for the kinematic chain and from an a priori model and constraints of the kinematic chain.

Claims

1. An apparatus comprising:

a kinematic chain comprising a proximal end and a distal end flexibly coupled to the proximal end;

a shape sensing optical fiber associated with the kinematic chain, wherein a shape sensing segment in the optical fiber is defined in the fiber between the proximal end and the distal end, and wherein a three-dimensional reference frame is defined at a start location of the shape sensing segment;

an interrogator that outputs strain information associated with shape sensing segment; and

an electronic data processor that receives the strain information and outputs a Cartesian position of an end point of shape sensing segment with respect to the reference frame.

2. The apparatus of claim 1:

wherein the reference frame comprises an x-axis, a y-axis, and a z-axis; and

wherein the position is output as Δ

x, Δ

y, Δ

z.