# US 12,727,948 B2 · Advanced tracking array > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,727,948 B2 - Document ID: US12727948B2 - Status: Granted - Kind: B2 - Application number: 18/063,611 - Filed: 2022-12-08 - Published: 2024-06-13 - Granted: 2026-09-08 - Earliest claimed: 2022-12-08 - Assignees: Depuy Ireland Unlimited Company - Applicants: Depuy Ireland Unlimited Company - Inventors: William J. Long; Daniel Girardeau-Montaut - Web page: https://patentgrep.com/patent/US12727948B2 ## CPC - A61B 34/20: Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis - G06T 7/73: using feature-based methods - A61B 2034/105: {Modelling of the patient, e.g. for ligaments or bones} - A61B 2034/2048: {using an accelerometer or inertia sensor} - A61B 2034/2051: {Electromagnetic tracking systems} - A61B 2034/2055: {Optical tracking systems} - A61B 2034/2057: {Details of tracking cameras} - A61B 2034/2059: {Mechanical position encoders} - A61B 2034/2065: {Tracking using image or pattern recognition} - A61B 2034/2068: {using pointers, e.g. pointers having reference marks for determining coordinates of body points} - A61B 2034/2072: {Reference field transducer attached to an instrument or patient} - A61B 2090/365: {augmented reality, i.e. correlating a live optical image with another image} - A61B 2090/371: {with simultaneous use of two cameras} - A61B 2090/372: {Details of monitor hardware} - A61B 2090/3937: {Visible markers} - A61B 2090/3983: {Reference marker arrangements for use with image guided surgery} - G06T 2207/20061: Hough transform - G06T 2207/20081: Training; Learning - G06T 2207/30204: Marker - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL ## Abstract A tracking array tracking system, including: at least one processor; and at least one memory storing instructions, that when executed by the at least one processor, cause the tracking array system at least to: determine that one marker of a plurality of markers on a tracking array is obstructed to a camera system; identify marker lines on the tracking array; determine a location of the marker lines of the tracking array; and determine a location and orientation of the tracking array based upon the location of the marker lines. ## Claims ### Claim 1 A tracking array tracking system, comprising: at least one processor; and at least one memory storing instructions, that when executed by the at least one processor, cause the tracking array tracking system at least to: determine that one marker of a plurality of markers on a tracking array is obstructed to a camera system; identify a plurality of marker lines on the tracking array; determine a location and orientation of the marker lines of the tracking array; and determine a location and orientation of the tracking array based upon the location and orientation of the marker lines; wherein the step of identifying includes identifying, if the camera system has seen at least two marker line segments, a marker line of said plurality of marker lines comprising said at least two marker line segments when the at least two marker line segments are colinear. ### Claim 2 (depends on 1) The tracking array tracking system of claim 1, wherein the instructions further cause the tracking array tracking system at least to: determine a location of the plurality of markers on the tracking array; and determine a location and orientation of the tracking array based upon the location of the plurality of markers. ### Claim 3 (depends on 1) The tracking array tracking system of claim 1, wherein identifying marker lines includes using a Hough Transform. ### Claim 4 (depends on 1) The tracking array tracking system of claim 1, wherein identifying marker lines includes using a binarization process with a skeletonization process. ### Claim 5 (depends on 1) The tracking array tracking system of claim 1, wherein identifying marker lines includes using a machine learning pattern matching model. ### Claim 6 (depends on 1) The tracking array tracking system of claim 1, wherein determining location and orientation of the tracking array includes: determining a location of an intersection of marker lines proximate the obstructed reflective element; and determining a location of the obstructed marker based upon the location of the intersection of the marker lines. ### Claim 7 (depends on 1) The tracking array tracking system of claim 1, wherein the marker lines are curved. ### Claim 8 (depends on 1) The tracking array tracking system of claim 1, wherein the marker lines are one of reflective marker lines or active marker lines. ### Claim 9 A method for tracking a tracking array in a computer aided surgery system, comprising: determining that one reflective element of a plurality of markers on the tracking array is obstructed to a camera system; identifying a plurality of marker lines on the tracking array; determining a location and orientation of the marker lines of the tracking array; and determining a location and orientation of the tracking array based upon the location of the marker lines; wherein the step of identifying includes identifying, if the camera system has seen at least two marker line segments, a marker line of said plurality of marker lines comprising said at least two marker line segments when the at least two marker line segments are colinear. ### Claim 10 (depends on 9) The method of claim 9, further comprising: determining a location of the plurality of markers on the tracking array; and determining a location and orientation of the tracking array based upon the location of the plurality of markers. ### Claim 11 (depends on 9) The method of claim 9, wherein identifying marker lines includes using a Hough Transform. ### Claim 12 (depends on 9) The method of claim 9, wherein identifying marker lines includes using a binarization process with a skeletonization process. ### Claim 13 (depends on 9) The method of claim 9, wherein identifying marker lines includes using a machine learning pattern matching model. ### Claim 14 (depends on 9) The method of claim 9, wherein determining location and orientation of the tracking array includes: determining a location of an intersection of marker lines adjacent the obstructed reflective element; and determining a location of the obstructed marker based upon the location of the intersection of the marker lines. ### Claim 15 (depends on 9) The method of claim 9, wherein the marker lines are curved. ### Claim 16 (depends on 9) The method of claim 9, wherein the marker lines are one of reflective marker lines or active marker lines. ### Claim 17 A method for tracking a tracking array in a computer aided surgery system, comprising: identifying a plurality of marker lines on the tracking array; determining a location and orientation of the marker lines of the tracking array; and determining a location and orientation of the tracking array based upon the location and orientation of the marker lines; wherein the step of identifying includes identifying, if the camera system has seen at least two marker line segments, a marker line of said plurality of marker lines comprising said at least two marker line segments when the at least two marker line segments are colinear. ### Claim 18 (depends on 17) The method of claim 17, wherein identifying marker lines includes using a Hough Transform. ### Claim 19 (depends on 17) The method of claim 17, wherein identifying marker lines includes using one of a binarization process with a skeletonization process and a machine learning pattern matching model. ### Claim 20 (depends on 17) The method of claim 17, wherein determining location and orientation of the tracking array includes: determining locations of intersections of marker lines of the tracking array; and computing the location and orientation of the tracking array based upon the locations of the intersections of the marker lines of the tracking array. ### Claim 21 (depends on 17) The method of claim 17, wherein the marker lines are one of reflective marker lines or active marker lines.