Tool grip calibration for robotic surgery

• US 20050251110A1
• Filed: 05/04/2004
• Published: 11/10/2005
• Est. Priority Date: 05/04/2004
• Status: Active Grant

• Current Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Original Assignee: Intuitive Surgical Incorporated (Intuitive Surgical Holdings, LLC)
• Inventors: Nixon, Tom
• Granted Patent: US 7,386,365 B2
• Time in Patent Office: Days
• US Class Current: 606/1
• 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. A telesurgical system comprising:

an input handle having a first grip member movable relative to a second grip member in response to a hand gripping the handle;

a plurality of end effectors, each end effector comprising surgical jaws with a first end effector element movable relative to a second end effector element;

a manipulator transmitting a signal in response to mounting thereon of an end effector, the mounted end effector being from the plurality of end effectors; and

a processor coupling the input device to the manipulator, the processor configured to calibrate the mounted end effector and manipulator in response to the signal by effecting a calibration movement of at least one of the elements so as to bring the elements into mutual engagement, the processor configured to effect articulation of the jaws of the mounted end effector in response to the gripping of the handle per the calibration.

2. The telesurgical system of claim 1;

wherein an input linkage supports the handle and a robotic arm of the manipulator supports the mounted end effector, the input linkage and the robotic arm each having a plurality of degrees of freedom, the processor effecting movement of the robotic arm in response to articulation of the input linkage;

wherein the processor effects the calibration in response to mounting of the mounted end effector onto the robotic arm and before use of the end effector in a robotic surgical procedure; and

wherein the processor does not determine calibration from a calibration movement of at least one degree of freedom of the robotic arm between mounting of the mounted end effector and the robotic procedure, so that the processor selectively calibrates articulation of the jaws.

3. The telesurgical system of claim 2, and wherein the processor does not effect a calibration movement of any degree of freedom of the robotic arm between mounting of the mounted end effector and the robotic procedure other than articulation of the jaws.

4. The telesurgical system of claim 1, wherein the calibration compensates for manipulator offset and wear, surgical instrument offset and wear, and manipulator/surgical interfacing.

5. The telesurgical system of claim 1, wherein the processor comprises programming to effect calibration by monitoring commanded torque signals to at least one motor of the manipulator, by monitoring position of a drive system coupled to the end effector, and by identifying a change in the commanded torque and the drive position.

6. The telesurgical system of claim 5, wherein the processor comprises a filter, the processor determining the relationship by applying the filter to the commanded torque.

7. The telesurgical system of claim 5, wherein the processor determines an end-effector element initial engagement configuration using a second derivative of the commanded torque.

8. The telesurgical system of claim 7, wherein the input device applies a feedback force to the hand at a nominal closed position of the handle, and wherein the processor effects the calibration so that the end effector initial engagement configuration corresponds to the nominal closed position of the handle.

9. The telesurgical system of claim 7, wherein the handle comprises a biasing means for increasing resistance to gripping of the handle at the nominal closed position.

10. The telesurgical system of claim 1, further comprising a single element end-effector, wherein a signal is transmitted by the manipulator when the single element end-effector is mounted thereon, and wherein the processor effects no grip calibration in response to the signal.

11. The telesurgical system of claim 1, wherein the processor is configured to effect the calibration once per robotic surgical procedure for each end-effector mounted on the manipulator.

12. A telerobotic system comprising:

an input having a linkage supporting a handle, the handle having a first grip member that moves relative to a second grip member when a hand grips the handle, the linkage articulable for repositioning of the handle;

a plurality the end effectors, each end effector comprising articulable jaws with a first end effector element movable relative to a second end effector element;

a manipulator having a robotic arm movably supporting a mounted end effector from among the plurality of end effectors; and

a processor coupling the input device to the manipulator, the processor determining a calibration of the mounted end effector by effecting a calibration movement of the end effector elements into mutual engagement, the processor effecting articulation of the jaws of the mounted end effector in response to the gripping of the handle per the calibration.

13. A telesurgical method comprising:

mounting a first surgical end effector to a manipulator, the end effector comprising jaws with a first end effector element movable relative to a second end effector element;

calibrating the mounted first end effector and manipulator by moving at least one of the end effector elements so as to bring the elements into mutual engagement;

gripping a handle with a hand so that a first grip member moves relative to a second grip member;

computing an articulation signal in response to the gripping of the handle per the calibration; and

articulating the jaws in response to the articulation signal so that the jaws of the first end effector move in correlation with the gripping of the handle.

14. The telesurgical method of claim 13, wherein the calibration is performed in response to mounting of the first end effector onto the manipulator and before use of the fist end effector in a robotic surgical procedure, and further comprising:

articulating an input linkage supporting the handle by moving the handle with the hand, and robotically moving an arm of the manipulator supporting the mounted first end effector in response to movement of the handle, the input linkage and the robotic arm each moving with a plurality of degrees of freedom;

wherein the processor does not effect a calibration movement of at least one degree of freedom of the robotic arm between mounting of the first end effector and the robotic procedure, so that the calibration comprises selective calibrates of jaw articulation.

15. The telesurgical method of claim 14, and wherein the processor does not effect a calibration movement of any degree of freedom of the robotic arm between mounting of the fist end effector and the robotic procedure other than articulation of the jaws.

16. The telesurgical method of claim 13, wherein the calibration compensates for manipulator offset and wear, surgical instrument offset and wear, and manipulator/surgical interfacing.

17. The telesurgical method of claim 13, wherein the calibration comprises transmitting commanded torque signals to at least one motor of the manipulator, monitoring movement of a drive system coupled to the first end effector, and identifying an end-effector element initial engagement drive position from a change in a relationship between the commanded torque and the movement.

18. The telesurgical method of claim 17, wherein the change is identified at least in part by filtering torque/position data.

19. The telesurgical method of claim 17, identifying the change comprises determining a second derivative of torque/position data.

20. The telesurgical method of claim 17, wherein the handle applies a feedback force to the hand at a nominally closed configuration of the handle, and wherein calibration is performed so that the end effector engagement position corresponds to the nominal closed position of the handle.

21. The telesurgical method of claim 20, further comprising increasing resistance to gripping of the handle at the nominal closed position during the surgical procedure.

22. The telesurgical method of claim 13, wherein the calibration is effected at least in part in response to a signal transmitted from the manipulator in response to mounting of the first end effector thereon, and further comprising removing the first end effector from the manipulator and mounting a second end effector having a single end effector element to the manipulator, wherein a single element end effector signal is transmitted by the manipulator when the second end effector is mounted thereon, and wherein no grip calibration is performed in response to the single element end effector signal.

23. The telesurgial method of claim 13, further comprising performing the calibration once per robotic procedure for each end-effector mounted on the manipulator.