Method for passively decoupling torque applied by a remote actuator into an independently rotating member

• US 9,095,362 B2
• Filed: 11/15/2011
• Issued: 08/04/2015
• Est. Priority Date: 11/15/2010
• Status: Active Grant

• Current Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Original Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Inventors: Dachs, Gregory W. II, Zabinski, John W., Brisson, Gabriel F., Murphy, Todd
• Primary Examiner(s): Dowe, Katherine
• Assistant Examiner(s): OBU, KENDRA NNEAMAKA
• Application Number:
  US13/297,158
• Publication Number:
  US 20120150192A1
• Time in Patent Office: 1,358 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 17/00 Surgical instruments, devices or methods, e.g. tourniquets A61B18/00 takes precedence; contraceptive devices, pessaries, or applicators therefor A61F6/00; eye surgery A61F9/007; ear surgery A61F11/00
• CPC Class Codes: A61B 17/28 Surgical forceps for holding suture needles or materials A61B17/0483; for removing or smashing calculi A61B17/221; surgical scissors A61B17/3201 ; obstetrical forceps A61B17/44; for inserting intraocular lenses A61F2/1662; hand-held gripping tools in general B25B7/00 ]
• CPC Class Codes: A61B 17/29 Forceps for use in minimally invasive surgery
• CPC Class Codes: A61B 2017/00367 Details of actuation of instruments, e.g. relations between pushing buttons, or the like, and activation of the tool, working tip, or the like
• CPC Class Codes: A61B 2017/00398 using powered actuators, e.g. stepper motors, solenoids
• CPC Class Codes: A61B 2017/00477 Coupling A61B2017/0046 takes precedence
• CPC Class Codes: A61B 2017/2901 Details of shaft
• CPC Class Codes: A61B 2017/2903 transferring rotary motion
• CPC Class Codes: A61B 2017/2929 with a head rotatable about the longitudinal axis of the shaft
• CPC Class Codes: A61B 2017/293 with means preventing relative rotation between the shaft and the actuating rod
• CPC Class Codes: A61B 2017/2932 Transmission of forces to jaw members
• CPC Class Codes: A61B 2017/2936 Pins in guiding slots
• CPC Class Codes: A61B 2017/2938 Independently actuatable jaw members, e.g. two actuating rods
• CPC Class Codes: A61B 2017/2943 Toothed members, e.g. rack and pinion
• CPC Class Codes: A61B 2034/2059 Mechanical position encoders
• CPC Class Codes: A61B 2034/301 for introducing or steering flexible instruments inserted into the body, e.g. catheters or endoscopes
• CPC Class Codes: A61B 2034/302 specifically adapted for manipulations within body cavities, e.g. within abdominal or thoracic cavities
• CPC Class Codes: A61B 2034/303 specifically adapted for manipulations within body lumens, e.g. within lumen of gut, spine, or blood vessels
• CPC Class Codes: A61B 2034/715 Cable tensioning mechanisms for removing slack
• CPC Class Codes: A61B 2090/067 for measuring angles
• CPC Class Codes: A61B 34/30 : Surgical robots
• CPC Class Codes: A61B 34/32 : operating autonomously
• 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

Abstract

Surgical assemblies and related methods are disclosed that provide for the transmission of high levels of actuation torque to a rotary mechanism of an end effector supported by an independently rotatable main shaft without causing undesirable rotation of the main shaft. An input drive shaft is coupled with both the rotary mechanism and the main shaft via a transmission and a rotational coupling so that the main shaft is passively subjected to a counteracting torque opposite in direction to the actuation torque transmitted to the rotary mechanism so as to inhibit rotational driving of the main shaft by the transmitted actuation torque.

Claims

1. A minimally invasive robotic surgical assembly comprising:

a base;

a main shaft assembly rotationally mounted to the base, the main shaft assembly including a main shaft, an end effector supported by the main shaft, and a first end effector drive shaft drivingly coupled to the end effector;

a main shaft drive rotationally driving the main shaft relative to the base;

a first input drive shaft transmitting a first input torque; and

a first transmission having a first input link rotationally coupled to the first input drive shaft, a first output link rotationally coupled with the first end effector drive shaft, and a first base link, the first transmission providing a first gear ratio between the first input link and the first output link so as to transmit a first output torque to the main shaft assembly in response to the first input torque, a first end effector torque being transmitted by the first end effector drive shaft to the end effector in response to the first output torque, the first base link rotationally coupled with the main shaft by a second gear ratio such that the first base link, in response to the first input torque, transmits a first counteracting torque to the main shaft that is opposite in direction from the first output torque such that the first counteracting torque inhibits rotational driving of the main shaft assembly by the first output torque.

2. The surgical assembly of claim 1, wherein the first counteracting torque has a magnitude that is within 10 percent of a magnitude of the first output torque.

3. The surgical assembly of claim 2, wherein the magnitude of the first counteracting torque is within 2 percent of the magnitude of the first output torque.

4. The surgical assembly of claim 1, wherein the first output link is coupled with the first end effector drive shaft via a rotational coupling providing a non-unity gear ratio.

5. The surgical assembly of claim 1, wherein the main shaft assembly has a back-driving torque threshold such that the main shaft back drives the main shaft drive when the main shaft assembly is subject to a net torque over the back-driving torque threshold and does not back drive the main shaft drive when the main shaft assembly is subject to a net torque under the back-driving torque threshold, the first counteracting torque having a magnitude that differs from a magnitude of the first output torque by a first net torque magnitude that is less than the back-driving torque threshold.

6. The surgical assembly of claim 5, wherein the first net torque magnitude is less than 50 percent of the back-driving torque threshold.

7. The surgical assembly of claim 6, wherein the first net torque magnitude is less than 25 percent of the back-driving torque threshold.

8. The surgical assembly of claim 7, wherein the first net torque magnitude is less than 10 percent of the back-driving torque threshold.

9. The surgical assembly of claim 1, wherein the first transmission comprises a first planetary gear box having a first sun gear, a first ring gear, and first planetary gears supported by a first carrier.

10. The surgical assembly of claim 9, wherein the first sun gear corresponds to the first input link, the first carrier corresponds to the first output link, and the first ring gear corresponds to the first base link.

11. The surgical assembly of claim 9, wherein the first carrier corresponds to the first input link, the first sun gear corresponds to the first output link, and the first ring gear corresponds to the first base link.

12. The surgical assembly of claim 9, wherein the first carrier or the first sun gear corresponds to the first base link.

13. The surgical assembly of claim 1, wherein a rotation of the main shaft induces a rotation of the first end effector drive shaft that is less than 10 percent of the rotation of the main shaft.

14. The surgical assembly of claim 13, wherein the induced rotation of the first end effector drive shaft is less than 5 percent of the rotation of the main shaft.

15. The surgical assembly of claim 1, further comprising:

a second end effector drive shaft drivingly coupled to the end effector and included in the main shaft assembly;

a second input drive shaft transmitting a second input torque; and

a second transmission having a second input link rotationally coupled to the second input drive shaft, a second output link rotationally coupled to the second end effector drive shaft, and a second base link, the second transmission providing a third gear ratio between the second input link and the second output link so as to transmit a second output torque to the main shaft assembly in response to the second input torque, a second end effector torque being transmitted by the second end effector drive shaft to the end effector in response to the second output torque, the second base link rotationally coupled with the main shaft by a fourth gear ratio such that the second base link, in response to the second input torque, transmits a second counteracting torque to the main shaft that is opposite in direction from the second output torque such that the second counteracting torque inhibits rotational driving of the main shaft assembly by the second output torque.

16. The surgical assembly of claim 15, wherein the second counteracting torque has a magnitude that is within 10 percent of a magnitude of the second output torque.

17. The surgical assembly of claim 16, wherein the magnitude of the second counteracting torque is within 2 percent of the magnitude of the second output torque.

18. The surgical assembly of claim 15, wherein the second output link is coupled with the second end effector drive shaft via a rotational coupling providing a non-unity gear ratio.

19. The surgical assembly of claim 15, comprising a common drive shaft through which the first and second base links are rotationally coupled with the main shaft.

20. The surgical assembly of claim 15, wherein the main shaft assembly has a back-driving torque threshold such that the main shaft back drives the main shaft drive when the main shaft assembly is subject to a net torque over the back-driving torque threshold and does not back drive the main shaft drive when the main shaft assembly is subject to a net torque under the back-driving torque threshold, of the second counteracting torque having a magnitude that differs from a magnitude of the second output torque by a second net torque magnitude that is less than the back-driving torque threshold.

21. The surgical assembly of claim 20, wherein the second net torque magnitude is less than 50 percent of the back-driving torque threshold.

22. The surgical assembly of claim 21, wherein the second net torque magnitude is less than 25 percent of the back-driving torque threshold.

23. The surgical assembly of claim 22, wherein the second net torque magnitude is less than 10 percent of the back-driving torque threshold.

24. The surgical assembly of claim 15, wherein the second transmission comprises a second planetary gear box having a second sun gear, a second ring gear, and second planetary gears supported by a second carrier.

25. The surgical assembly of claim 24, wherein the second sun gear corresponds to the second input link, the second carrier corresponds to the second output link, and the second ring gear corresponds to the second base link.

26. The surgical assembly of claim 24, wherein the second carrier corresponds to the second input link, the second sun gear corresponds to the second output link, and the second ring gear corresponds to the second base link.

27. The surgical assembly of claim 24, wherein the second carrier or the second sun gear corresponds to the second base link.

28. The surgical assembly of claim 24, wherein the first transmission comprises a first planetary gear box having a first sun gear, a first ring gear, and first planetary gears supported by a first carrier.

29. The surgical assembly of claim 28, wherein the first sun gear corresponds to the first input link, the first carrier corresponds to the first output link, and the first ring gear corresponds to the first base link.

30. The surgical assembly of claim 28, wherein the first carrier corresponds to the first input link, the first sun gear corresponds to the first output link, and the first ring gear corresponds to the first base link.

31. A method for preventing an actuation torque transmitted to an end effector from back driving a back-drivable main shaft during surgery, the method comprising:

rotating a first input link of a first transmission providing a first gear ratio between the first input link and a first output link of the first transmission, the first output link rotationally coupled with a main shaft assembly rotationally mounted to a base and including a main shaft and an end effector supported by the main shaft, a first output torque being transmitted by the first output link to the main shaft assembly and a first end effector torque being transmitted to the end effector in response to the first output torque, the first output torque being greater than a back-driving torque threshold for the main shaft assembly; and

transmitting torque from a first base link of the first transmission through a first rotational coupling between the first base link and the main shaft, the first rotational coupling providing a second gear ratio between the first base link and the main shaft such that a first counteracting torque is applied to the main shaft that is opposite in direction from the first output torque, the first counteracting torque inhibiting rotational driving of the main shaft assembly by the first output torque.

32. The method of claim 31, wherein the first net torque has a magnitude that is less than 50 percent of the back-driving torque threshold.

33. The method of claim 32, wherein the first net torque magnitude is less than 25 percent of the back-driving torque threshold.

34. The method of claim 33, wherein the first net torque magnitude is less than 10 percent of the back-driving torque threshold.

35. The method of claim 31, wherein the first counteracting torque has a magnitude that is within 10 percent of the magnitude of the first output torque.

36. The method of claim 35, wherein the magnitude of the first counteracting torque is within 2 percent of the magnitude of the first output torque.

37. The method of claim 31, wherein a first end effector drive shaft transmits the first end effector torque to the end effector and a rotation of the main shaft induces a rotation of the first end effector drive shaft that is less than 10 percent of the rotation of the main shaft.

38. The method of claim 37, wherein the induced rotation of the first end effector drive shaft is less than 5 percent of the rotation of the main shaft.

39. The method of claim 31, further comprising:

rotating a second input link of a second transmission providing a third gear ratio between the second input link and a second output link of the second transmission, the second output link rotationally coupled with the main shaft assembly so that a second output torque is transmitted by the second output link to the main shaft assembly and a second end effector torque is transmitted to the end effector in response to the second output torque, the second output torque being greater than the back-driving torque threshold; and

transmitting torque from a second base link of the second transmission through a second rotational coupling between the second base link and the main shaft, the second rotational coupling providing a fourth gear ratio between the second base link and the main shaft such that a second counteracting torque is applied to the main shaft that is opposite in direction from the second output torque, the second counteracting torque inhibiting rotational driving of the main shaft assembly by the second output torque.

40. The The method of claim 39, wherein the first and second rotational couplings share a common drive shaft.