RATCHETING FOR MASTER ALIGNMENT OF A TELEOPERATED MINIMALLY INVASIVE SURGICAL INSTRUMENT

• US 20160157949A1
• Filed: 01/14/2016
• Published: 06/09/2016
• Est. Priority Date: 06/30/2009
• Status: Active Grant

• Current Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Original Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Inventors: Itkowitz, Brandon D., DiMaio, Simon P., Nowlin, William C., Niemeyer, Gunter D., Mintz, David S.
• Granted Patent: US 9,579,164 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 2017/00725 Calibration or performance testing
• CPC Class Codes: A61B 2034/305 Details of wrist mechanisms at distal ends of robotic arms
• CPC Class Codes: A61B 34/25 User interfaces for surgical systems
• CPC Class Codes: A61B 34/30 Surgical robots
• CPC Class Codes: A61B 34/35 for telesurgery
• CPC Class Codes: A61B 34/37 Master-slave robots A61B34/35 takes precedence
• CPC Class Codes: A61B 34/77 Manipulators with motion or force scaling
• CPC Class Codes: A61B 90/10 for stereotaxic surgery, e.g. frame-based stereotaxis
• CPC Class Codes: B25J 3/00 Manipulators of master-slave type, i.e. both controlling unit and controlled unit perform corresponding spatial movements
• CPC Class Codes: B25J 9/1669 characterised by special application, e.g. multi-arm co-operation, assembly, grasping
• CPC Class Codes: B25J 9/1689 Teleoperation
• CPC Class Codes: G05B 2219/45117 Medical, radio surgery manipulator
• CPC Class Codes: Y10S 901/27 Arm part
• CPC Class Codes: Y10S 901/41 Tool

Abstract

A minimally-invasive surgical system includes a slave surgical instrument having a slave surgical instrument tip and a master grip. The slave surgical instrument tip has an alignment in a common frame of reference and the master grip, which is coupled to the slave surgical instrument, has an alignment in the common frame of reference. An alignment error, in the common frame of reference, is a difference in alignment between the alignment of the slave surgical instrument tip and the alignment of the master grip. A ratcheting system (i) coupled to the master grip to receive the alignment of the master grip and (ii) coupled to the slave surgical instrument, to control motion of the slave by continuously reducing the alignment error, as the master grip moves, without autonomous motion of the slave surgical instrument tip and without autonomous motion of the master grip.

Claims

1-20. -20. (canceled)

21. A method comprising:

characterizing, by a ratcheting system in a surgical system, a first alignment error that is a difference between a first alignment of a master grip of the surgical system and a first alignment of a slave instrument tip of a slave surgical instrument of the surgical system;

determining, by the ratcheting system, a new alignment error that is a difference between a second alignment of the master grip and the first alignment of the slave surgical instrument tip; and

using, by the ratcheting system, the new alignment error to control motion of the surgical instrument tip only if the new alignment error is smaller than the first alignment error.

22. The method of claim 21:

wherein the first alignment error comprises a first orientation error; and

wherein the new alignment error comprises a new orientation error.

23. The method of claim 22, wherein the first orientation error comprises an angle.

24. The method of claim 23:

wherein the angle (θ

_e) is expressed as;

θ

_e=cos<sup>−

1</sup>[0.5*(R<sub>Δ

11</sub>+R<sub>Δ

22</sub>+R<sub>Δ

33</sub>−

1)], and

wherein R<sub>Δ

11</sub>, R<sub>Δ

22</sub>, R<sub>Δ

33</sub> are diagonal elements of a relative rotation matrix R<sub>Δ

-first</sub>.

25. The method of claim 23, wherein the angle is one Euler angle in a set of Euler angles.

26. The method of claim 22, wherein the new orientation error comprises an angle.

27. The method of claim 26:

wherein the angle (θ

_e) is expressed as;

θ

_e=cos<sup>−

1</sup>[0.5*(R<sub>Δ

11</sub>+R<sub>Δ

22</sub>+R<sub>Δ

33</sub>−

1)], and

wherein R<sub>Δ

11</sub>, R<sub>Δ

22</sub>, R<sub>Δ

33</sub> are diagonal elements of a relative rotation matrix R<sub>Δ

-new</sub>.

28. The method of claim 26, wherein the angle is one Euler angle in a set of Euler angles.

29. The method of claim 21, further comprising:

constraining, by the ratcheting system, roll motion of the slave surgical instrument tip if a joint limit is reached during motion of the slave surgical instrument tip.

30. The method of claim 21, further comprising:

introducing, by the ratcheting system, a control system error in the new alignment error to speed up convergence of alignment between the slave surgical instrument tip and the master grip.

31. The method of claim 21, further comprising:

determining, by the ratcheting system, a first orientation solution closest to an orientation of the master grip from multiple orientation solutions; and

using the first orientation solution to determine the new alignment error.

32. The method of claim 21, the master grip comprising an unpowered master grip.

33. The method of claim 21, further comprising:

performing the determining and the using the new alignment error while the master grip is used to control the slave surgical instrument tip.