Tool grip calibration for robotic surgery

• US 9,085,083 B2
• Filed: 05/08/2014
• Issued: 07/21/2015
• Est. Priority Date: 05/04/2004
• Status: Active Grant

• Current Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Original Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Inventors: Nixon, Tom
• Primary Examiner(s): Marc, McDieunel
• Application Number:
  US14/272,862
• Publication Number:
  US 20140330434A1
• Time in Patent Office: 439 Days
• Field of Search: 700/45, 700/245, 700/247, 700/248, 700/251, 700/254, 700/259, 700/260, 700/261, 700/262, 700/263, 700/264, 901/8, 901/9, 901/14, 901/15, 901/21, 901/22, 901/24, 901/29, 901/30, 901/34, 901/36, 901/39, 901/40, 901/44, 901/45, 901/46, 901/48, 414/4, 414/5, 414/729, 414/730, 414/735, 414/744.5, 318/568.1, 318/568.11, 318/568.12, 318/568.18, 318/568.21, 318/568.24, 318/646, 128/897, 294/479.01, 606/1, 606/33, 606/130, 606/205, 623/62, 244/172.5, 294/28
• US Class Current: 1/1
• CPC Class Codes: A61B 17/29 Forceps for use in minimally invasive surgery
• CPC Class Codes: A61B 2017/00017 Electrical control of surgical instruments
• CPC Class Codes: A61B 2017/00207 with hand gesture control or hand gesture recognition
• CPC Class Codes: A61B 2017/00477 Coupling A61B2017/0046 takes precedence
• 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 2090/066 for measuring torque
• 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 34/70 Manipulators specially adapted for use in surgery
• CPC Class Codes: A61B 34/71 Manipulators operated by drive cable mechanisms
• CPC Class Codes: A61B 90/06 Measuring instruments not otherwise provided for
• CPC Class Codes: A61B 90/361 Image-producing devices, e.g. surgical cameras
• CPC Class Codes: B25J 9/1689 Teleoperation
• CPC Class Codes: B25J 9/1692 Calibration of manipulator
• CPC Class Codes: G05B 2219/45123 Electrogoniometer, neuronavigator, medical robot used by surgeon to operate
• CPC Class Codes: G05B 2219/49305 Store, memory on tool with control and maintenance data
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass
• CPC Class Codes: Y10S 901/39 Jaw structure
• CPC Class Codes: Y10S 901/40 : Vacuum or mangetic
• CPC Class Codes: Y10S 901/44 : inspection
• CPC Class Codes: Y10S 901/45 : Compliance
• CPC Class Codes: Y10S 901/46 : Sensing device

Abstract

Telerobotic, telesurgical, and surgical robotic devices, systems, and methods selectively calibrate end effector jaws by bringing the jaw elements into engagement with each other. Commanded torque signals may bring the end effector elements into engagement while monitoring the resulting position of a drive system, optionally using a second derivative of the torque/position relationship so as to identify an end effector engagement position. Calibration can allow the end effector engagement position to correspond to a nominal closed position of an input handle by compensating for wear on the end effector, the end effector drive system, then manipulator, the manipulator drive system, the manipulator/end effector interfacing, and manufacturing tolerances.

Claims

1. An apparatus comprising:

input grip handles;

a biasing element for increasing resistance to gripping of the input grip handles beginning at a nominal closed position;

a processor;

a memory storing instructions for causing the processor to;

identify mounting of an end effector on a manipulator controlled by the processor, the end effector comprising end effector elements;

drive one or more motors of the manipulator with a commanded torque to move the end effector elements relative to each other in response to gripping of the input grip handles;

monitor a joint position of the end effector elements relative to the commanded torque;

determine a joint position of mutual engagement of the end effector elements based on change in the commanded torque; and

set the nominal closed position of the input grip handles as corresponding to the joint position of mutual engagement of the end effector elements.

2. The apparatus of claim 1, the memory further storing instructions for causing the processor to:

increase the resistance to gripping of the input grip handles by commanding a motor to drive the bias element.

3. The apparatus of claim 1, the biasing means comprising a spring.

4. The apparatus of claim 1, the biasing means comprising a resilient bumper.

5. The apparatus of claim 1, the memory further storing instructions for causing the processor to:

identify mounting of a single-element end effector on the manipulator;

in response to identifying the mounting of the single-element end effector, forego the driving, monitoring, and determining the monitored position.

6. The apparatus of claim 1, the memory further storing instructions for causing the processor to:

store the determined position corresponding to mutual engagement of the mounted end effector elements in the memory;

apply the determined position as an offset between the position of input grip handles coupled to the processor and the position of the end effector elements when the end effector is remounted on the manipulator.

7. The apparatus of claim 1, the memory further storing instructions for causing the processor to:

store in the memory calibration offsets comprising at least one of offsets of the end effector, offsets of the manipulator, or interface offsets resulting from the combination of a tool interface with a holder; and

apply the calibration offsets during operation of the system.

8. The apparatus of claim 1, the memory further storing instructions for causing the processor to:

filter the commanded torque;

calculate a second derivative of the filtered commanded torque;

identify a minima or maxima of the second derivative; and

identify a joint position corresponding to the identified maxima or minima in the second derivative as corresponding to mutual engagement of the end effector elements.

9. The apparatus of claim 1, the memory further storing instructions for causing the processor to:

not calibrate movement of any other degree of freedom of the manipulator between the identified mounting of the end effector and operation of a robotic procedure.

10. The apparatus of claim 1, further comprising:

the manipulator.

11. A method comprising:

identifying mounting of an end effector on a manipulator controlled by the processor, the end effector comprising end effector elements;

driving one or more motors of the manipulator with a commanded torque to move the end effector elements relative to each other;

monitoring a joint position of the end effector elements relative to the commanded torque;

determining a monitored position as corresponding to a mutual engagement of the end effector elements based on a change in the commanded torque;

driving the one or more motors of the manipulator in response to movement of input grip handles coupled to the processor; and

applying a feedback force to the input grip handles when the position of the input grip handles corresponds to mutual engagement of the end effector elements.

12. The method of claim 11, further comprising:

applying the feedback force by increasing resistance to gripping of the input grip handles.

13. The method of claim 11, further comprising:

identifying mounting of a single-element end effector on the manipulator;

foregoing the driving, monitoring, and determining the monitored position in response to identifying the mounting of the single-element end effector.