TOOL GRIP CALIBRATION FOR ROBOTIC SURGERY

• US 20120083801A1
• Filed: 09/27/2011
• Published: 04/05/2012
• Est. Priority Date: 05/04/2004
• Status: Active Grant

• Current Assignee: Intuitive Surgical Incorporated (Intuitive Surgical Holdings, LLC)
• Original Assignee: Intuitive Surgical Incorporated (Intuitive Surgical Holdings, LLC)
• Inventors: Nixon, Tom
• Granted Patent: US 8,452,447 B2
• Time in Patent Office: Days
• US Class Current: 606/130
• 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

1-37. -37. (canceled)

38. An apparatus comprising:

an input handle having a first grip member movable relative to a second grip member;

an end effector comprising a first end effector element movable relative to a second end effector element;

a processor configured to generate a commanded torque to move the first end effector element relative to the second end effector element in response to the first grip member being moved relative to the second grip member, and further to monitor a nominal position of the first end effector element relative to the second end effector element; and

a memory storing an offset between an actual mutual engagement between the first and second end effector elements and a nominal mutual engagement between the first end second end effector elements;

wherein the processor is configured to map a position of mutual engagement between the first and second grip members to an actual position of mutual engagement between the first and second end effector elements using said stored offset.

39. The apparatus of claim 38, the processor further configured to determine said stored offset by monitoring the nominal position relative to the commanded torque during a calibration phase.

40. The apparatus of claim 39, the processor further configured to determine said stored offset by determining a nominal position associated with a relative increase in the commanded torque applied.

41. The apparatus of claim 39, the processor further configured to filter the commanded torque.

42. The apparatus of claim 40, the processor further configured to compute a second derivative of the command torque to determine the relative increase.

43. The apparatus of claim 38, wherein the input handle comprises a biasing means for increasing resistance to gripping of the handle at the nominal closed position.

44. The apparatus of claim 39, further comprising a manipulator releasably coupleable to an instrument comprising the end effector, the processor configured to commence said calibration phase upon detecting the instrument being coupled to the manipulator.

45. An apparatus comprising:

an input handle having a first grip member movable relative to a second grip member;

a manipulator operable to drive a releasably coupleable surgical instrument, the instrument comprising a first end effector element movable relative to a second end effector element;

a processor coupled to the manipulator, the processor configured to generate a commanded torque to move the first end effector element relative to the second end effector element in response to the first grip member being moved relative to the second grip member, and further to monitor a nominal position of the first end effector element relative to the second end effector element; and

a memory storing an offset between an actual mutual engagement between the first and second end effector elements and a nominal mutual engagement between the first end second end effector elements;

wherein the processor is configured to map a position of mutual engagement between the first and second grip members to an actual position of mutual engagement between the first and second end effector elements using said stored offset.

46. The apparatus of claim 45, the processor further configured to determine said stored offset by monitoring the nominal position relative to the commanded torque during a calibration phase.

47. The apparatus of claim 46, the processor further configured to determine said stored offset by determining a nominal position associated with a relative increase in the commanded torque applied.

48. The apparatus of claim 46, the processor further configured to filter the commanded torque.

49. The apparatus of claim 47, the processor further configured to compute a second derivative of the command torque to determine the relative increase.

50. The apparatus of claim 45, wherein the input handle comprises a biasing means for increasing resistance to gripping of the handle at the nominal closed position.

51. The apparatus of claim 46, the processor configured to commence said calibration phase upon detecting the instrument being coupled to the manipulator.