Navigation systems and methods for indicating and reducing line-of-sight errors

• US 9,566,120 B2
• Filed: 01/16/2014
• Issued: 02/14/2017
• Est. Priority Date: 01/16/2013
• Status: Active Grant

• Current Assignee: Stryker Corporation
• Original Assignee: Stryker Corporation
• Inventors: Malackowski, Donald W., Moctezuma de la Barrera, Jose Luis
• Primary Examiner(s): Bates, David
• Assistant Examiner(s): Chang, Olivia C
• Application Number:
  US14/156,856
• Publication Number:
  US 20140200621A1
• Time in Patent Office: 1,125 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 17/8057 the interlocking form comprising a thread
• CPC Class Codes: A61B 17/808 Instruments for holding or positioning bone plates, or for adjusting screw-to-plate locking mechanisms
• CPC Class Codes: A61B 17/809 with bone-penetrating elements, e.g. blades or prongs bone staples A61B17/0642; intramedullary nails with a plate at an end A61B17/7233
• CPC Class Codes: A61B 17/8875 Screwdrivers, spanners or wrenches
• CPC Class Codes: A61B 17/92 Impactors or extractors, e.g. for removing intramedullary devices insertion or extraction of artificial joints A61F2/4603
• CPC Class Codes: A61B 2017/00115 with audible or visual output with imaging means A61B90/37, A61B34/20
• CPC Class Codes: A61B 2017/00119 alarm; indicating an abnormal situation
• CPC Class Codes: A61B 2034/2048 using an accelerometer or inertia sensor
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2034/2055 Optical tracking systems
• CPC Class Codes: A61B 2034/2063 Acoustic tracking systems, e.g. using ultrasound
• CPC Class Codes: A61B 2034/2068 using pointers, e.g. pointers having reference marks for determining coordinates of body points
• CPC Class Codes: A61B 2090/3945 Active visible markers, e.g. light emitting diodes
• CPC Class Codes: A61B 2090/3983 Reference marker arrangements for use with image guided surgery
• CPC Class Codes: A61B 2090/3991 having specific anchoring means to fixate the marker to the tissue, e.g. hooks
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 34/30 Surgical robots
• CPC Class Codes: A61B 34/70 Manipulators specially adapted for use in surgery
• CPC Class Codes: A61B 90/10 for stereotaxic surgery, e.g. frame-based stereotaxis

Abstract

Navigation systems and methods used to track objects moving in space. One navigation system and method employs trackers having light emitters for indicating when line-of-sight between tracking elements on the trackers and sensors is obstructed or for other errors. Another navigation system and method instructs users on how to place a tracker with respect to an object to reduce line-of-sight issues during a surgical procedure.

Claims

1. A navigation system for tracking a plurality of objects, said navigation system comprising:

a sensor;

a plurality of tracking devices attachable to the plurality of objects, with each of said tracking devices including;

a tracking head having a tracking body and a tracking element that is coupled to said tracking body and configured to transmit a tracking signal to said sensor to determine a position of one of the plurality of objects; and

an error indicator supported by said tracking head and configured to indicate an error in said sensor receiving said tracking signal from said tracking element, said error indicator including a first light emitting diode attached to said tracking body and a second light emitting diode attached to said tracking body;

a computing system configured to;

determine if said sensor received said tracking signal from said tracking element, generate an error signal if said sensor did not receive said tracking signal, and control activation of said first and second light emitting diodes of said error indicator plurality of error indicator to emit a first colored light in response to generating said error signal and to emit a second colored light in the absence of said error signal.

2. A navigation system as set forth in claim 1 wherein said computing system is configured to activate said first light emitting diode to emit said first colored light in response to generating said error signal and deactivate said second light emitting diode to discontinue emitting said second colored light in response to generating said error signal.

3. A navigation system as set forth in claim 1 wherein said computing system is configured to activate said first and second light emitting diodes to emit said first colored light in response to generating said error signal and to emit said second colored light in the absence of said error signal.

4. A navigation system as set forth in claim 1 wherein said tracking body includes a top, bottom, and sides, said tracking body defining a light opening in said sides to receive said first colored light and said second colored light from said first and second light emitting diodes.

5. A navigation system as set forth in claim 1 wherein said sensor has a field of view and each one of said plurality of tracking devices is attachable to a corresponding one of the plurality of objects so that said tracking element is in said field of view.

6. A navigation system as set forth in claim 1 wherein said tracking head of each one of said plurality of tracking devices further comprises a second tracking element.

7. A navigation system as set forth in claim 6 wherein said tracking elements are line-of-sight tracking elements.

8. A navigation system as set forth in claim 6 wherein said tracking elements are light emitting diodes.

9. A navigation system as set forth in claim 6 wherein said tracking elements are reflector balls.

10. A navigation system as set forth in claim 1 wherein said tracking head of each one of said plurality of tracking devices further comprises second and third tracking elements for transmitting tracking signals.

11. A navigation system as set forth in claim 10 wherein said computing system is configured to:

determine if said sensor receives said tracking signals from all three of said tracking elements of said tracking head in a tracking cycle that includes sequential activation of all three of said tracking elements; and

generate said error signal if said sensor did not receive said tracking signals from all three of said tracking elements of said tracking head in said tracking cycle.

12. A navigation system for tracking a plurality of objects, said navigation system comprising:

a computer cart assembly comprising a computer and an optical position sensor communicating with one another; and

a plurality of tracking devices attachable to the plurality of objects, with each of said tracking devices including;

a tracking head having a tracking body and a tracking element that is coupled to said tracking body and configured to transmit a tracking signal to said optical position sensor for determining a position of one of the plurality of objects; and

an error indicator supported by said tracking head and configured to indicate an error in said sensor receiving said tracking signal from said tracking element, said error indicator including a first light emitting diode attached to said tracking body and a second light emitting diode attached to said tracking body;

wherein said computer is configured to;

determine if said optical position sensor received said tracking signal from said tracking element, generate an error signal if said sensor did not receive said tracking signal from said tracking element, and control activation of said light emitters first and second light emitting diodes of said error indicator to emit a first colored light in response to generating said error signal and to emit a second colored light in the absence of said error signal.

13. A navigation system as set forth in claim 12 further wherein said computer cart assembly includes an arm and a camera unit coupled to said arm, with said camera unit including said optical position sensor.

14. A method for tracking a plurality of objects using a navigation system comprising a sensor and a plurality of tracking devices, said method comprising the steps of:

providing the plurality of tracking devices attachable to the plurality of objects, with each of the tracking devices including;

a tracking head having a tracking body and a tracking element that is coupled to the tracking body and configured to transmit a tracking signal to the sensor to determine a position of one of the plurality of objects; and

an error indicator supported by the tracking head and configured to indicate an error in the sensor receiving the tracking signal from the tracking element, the error indicator including a first light emitting diode attached to the tracking body and a second light emitting diode attached to the tracking body;

transmitting the tracking signal from the tracking element to the sensor while the tracking device is attached to the object;

determining if the sensor received the tracking signal from the tracking element;

generating an error signal if the sensor did not receive the tracking signal; and

controlling activation of the first and second light emitting diodes supported by the tracking head to emit a first colored light in response to generating the error signal and to emit a second colored light in the absence of the error signal.

15. A method as set forth in claim 14 wherein controlling activation of the first and second light emitting diodes includes activating the first light emitting diode to emit the first colored light in response to generating the error signal and deactivating the second light emitting diode to discontinue emitting the second colored light in response to generating the error signal.

16. A method as set forth in claim 14 wherein controlling activation of the first and second light emitting diodes includes activating the first and second light emitting diodes to emit the first colored light in response to generating the error signal and to emit the second colored light in the absence of the error signal.

17. A method as set forth in claim 14 wherein controlling activation of the first and second light emitting diodes to emit the first colored light and the second colored light includes emitting the first colored light and the second colored light through a light opening defined in sides of a tracking body.

18. A method as set forth in claim 14 wherein the tracking device is attached to the object so that the tracking element is within a field of view of the sensor.

19. A method as set forth in claim 14 wherein the tracking head has second and third tracking elements and said method further comprises transmitting tracking signals from the second and third tracking elements.

20. A method as set forth in claim 19 including determining if the sensor receives the tracking signals from all three of the tracking elements of the tracking head in a tracking cycle that includes sequential activation of all three of the tracking elements and generating the error signal if the sensor did not receive the tracking signals from all three of the tracking elements of the tracking head in the tracking cycle.