INSTRUMENT CARRIAGE ASSEMBLY FOR SURGICAL SYSTEM

• US 20130325034A1
• Filed: 05/31/2013
• Published: 12/05/2013
• Est. Priority Date: 06/01/2012
• Status: Active Grant

• Current Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Original Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Inventors: SCHENA, Bruce Michael, DACHS, Gregory W. II, SOLOMON, Todd
• Granted Patent: US 9,452,019 B2
• Time in Patent Office: Days
• US Class Current: 606/130
• CPC Class Codes: A61B 2017/00477 Coupling A61B2017/0046 takes precedence
• CPC Class Codes: A61B 2034/2059 Mechanical position encoders
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 34/30 Surgical robots
• CPC Class Codes: A61B 34/37 Master-slave robots A61B34/35 takes precedence
• CPC Class Codes: A61B 90/98 using electromagnetic means, e.g. transponders

Abstract

A robotic assembly is configured to support, insert, retract, and actuate a surgical instrument mounted to the robotic assembly. The robotic assembly includes an instrument holder base member, a motor housing moveably mounted to the instrument holder base member, a carriage drive mechanism operable to translate the motor housing along the instrument holder base member, a plurality of drive motors, and a plurality of output drive couplings driven by the drive motors. One or more of the drive motors includes one or more magnetic flux shields to inhibit magnetic interference with an adjacent drive motor and/or with an adjacent motor orientation sensor.

Claims

1. A robotic assembly configured to support, insert, retract, and actuate a surgical instrument mounted to the robotic assembly, the robotic assembly comprising:

an instrument holder base member;

a motor housing moveably mounted to the instrument holder base member;

a carriage drive mechanism operable to selectively translate the motor housing relative to the instrument holder base member along an insertion axis of the surgical instrument;

a plurality of drive motors, each of the drive motors being mounted to the motor housing, one or more of the drive motors including a magnetic flux shield; and

a plurality of output drive couplings, each of the output drive couplings being drivingly coupled with a corresponding one of the drive motors, each of the output drive couplings being configured to drivingly couple with a corresponding input drive coupling of the surgical instrument.

2. The robotic assembly of claim 1, wherein at least one of the drive motors includes a brushless component motor.

3. The robotic assembly of claim 2, wherein at least one of the drive motors includes a brushless component motor having a trapezoidal-commutation motor constant greater than or equal to 1.25 oz.-in/sqrt(Watt).

4. The robotic assembly of claim 1, wherein the magnetic flux shield includes a ring made of magnetically soft material containing at least one of iron, cobalt, or nickel.

5. The robotic assembly of claim 1, wherein at least one of the drive motors includes two magnetic flux shields that are disposed at opposite ends of the drive motor.

6. The robotic assembly of claim 1, wherein each of the drive motors includes two magnetic flux shields that are disposed at opposite ends of the drive motor.

7. The robotic assembly of claim 6, wherein each of the magnetic flux shields comprises a ferrous ring.

8. The robotic assembly of claim 1, wherein two of the drive motors are separated by less than 5 mm.

9. The robotic assembly of claim 8, wherein two of the drive motors are separated by less than 2 mm.

10. The robotic assembly of claim 1, wherein:

the drive motors include five drive motors; and

each of the five drive motors is separated from at least two of the other drive motors by less than 5 mm.

11. The robotic assembly of claim 10, wherein each of the five drive motors is separated from at least two of the other drive motors by less than 2 mm.

12. A robotic assembly configured to support, insert, retract, and actuate a surgical instrument mounted to the robotic assembly, the robotic assembly comprising:

an instrument holder base member;

a motor housing moveably mounted to the instrument holder base member;

a carriage drive mechanism operable to selectively translate the motor housing relative to the instrument holder base member along an insertion axis of the surgical instrument;

a plurality of drive motors, each of the drive motors being mounted to the motor housing;

a plurality of gear boxes, each of the gear boxes being drivingly coupled with one of the drive motors;

a plurality of output drive couplings, each of the output drive couplings being drivingly coupled with a corresponding one of the gear boxes, each of the output drive couplings being configured to drivingly couple with a corresponding input drive coupling of the surgical instrument; and

a sensor assembly that includes an orientation sensor, a sensor target, and a sensor shaft drivingly coupling the sensor target to a corresponding one of the output drive couplings through an aperture in an outer housing of the corresponding gear box;

the sensor shaft being driven by an output link of the corresponding gear box that rotates in unison with the corresponding output drive coupling.

13. The robotic assembly of claim 12, wherein the orientation sensor optically reads the sensor target.

14. The robotic assembly of claim 12, comprising a plurality of sensor assemblies, each of the sensor assemblies including an orientation sensor, a sensor target, and a sensor shaft drivingly coupling the sensor target to a corresponding one of the output drive couplings through an aperture in an outer housing of the corresponding gear box;

each sensor shaft being driven by an output link of the corresponding gear box that rotates in unison with the corresponding output drive coupling.

15. The robotic assembly of claim 12, wherein the gear ratio between the sensor shaft and output drive coupling is exactly 1:

1.

16. The robotic assembly of claim 12, wherein the gear ratio between at least one of the motors and the corresponding output drive coupling is less than 40:

1.

17. The robotic assembly of claim 12, wherein each of the output gear boxes have two or fewer gear reduction stages.

18. The robotic assembly of claim 14, wherein the drive motors are disposed between the orientation sensors and the output drive couplings.

19. The robotic assembly of claim 18, wherein each of the sensor shafts is drivingly coupled to the corresponding output drive coupling via a sensor shaft gear that extends through the aperture in the corresponding outer housing to engage an output gear that rotates in unison with the corresponding output drive coupling.

20. The robotic assembly of claim 19, wherein:

two of the sensor shaft gears overlap along a shaft direction parallel to rotational axes of the sensor shafts; and

one or more of the corresponding apertures and output gears is configured to accommodate the overlap of the sensor shaft gears along the shaft direction.

21. The robotic assembly of claim 12, the gear boxes include a planetary gear box.

22. The robotic assembly of claim 21, wherein the planetary gear box includes a shaft bearing configured to react moment so as to inhibit an axis of rotation of an inner race of the shaft bearing from becoming misaligned with an axis of rotation of an outer race of the shaft bearing.

23. The robotic assembly of claim 22, wherein the shaft bearing includes two rows of rolling elements.

24. The robotic assembly of claim 21, wherein the planetary gear box includes a carrier gear that has external gear teeth that are engaged by a sensor shaft gear extending through the aperture, the sensor shaft gear being drivingly coupled with the sensor shaft.

25. A robotic assembly configured to support, insert, retract, and actuate a surgical instrument mounted to the robotic assembly, the robotic assembly comprising:

an instrument holder base member;

a motor housing moveably mounted to the instrument holder base member;

a carriage drive mechanism operable to selectively translate the motor housing relative to the instrument holder base member along an insertion axis of the surgical instrument;

five drive motors, each of the drive motors being mounted to the motor housing, each of the drive motors including a magnetic flux shield;

five gear boxes, each of the gear boxes being drivingly coupled with one of the drive motors;

five output drive couplings, each of the output drive couplings being drivingly coupled with a corresponding one of the gear boxes, each of the output drive couplings configured to be drivingly coupled with a corresponding input drive coupling of the surgical instrument; and

five sensor assemblies, each sensor assembly including an orientation sensor and a sensor shaft drivingly coupling the orientation sensor to a corresponding one of the output couplings through an aperture in an outer housing of the corresponding gear box, the sensor shaft being driven by an output link of the corresponding gear box that rotates in unison with the corresponding output drive coupling.

26. The robotic assembly of claim 25, wherein one or more of the axes of the output drive couplings are substantially parallel to the insertion axis.

27. The robotic assembly of claim 25, wherein the output drive couplings are arranged in a pattern with four corner output drive couplings and a central output drive coupling disposed between the four corner output drive couplings.

28. The robotic assembly of claim 25, wherein a maximum of two output drive couplings are stacked in a width direction of the motor housing.

29. The robotic assembly of claim 25, further comprising a radio frequency identification (RFID) antenna module designed to read an instrument RFID tag at a range between 0 mm and approximately 20 mm separation distance.

30. The robotic assembly of claim 25, comprising a circuit board including the five orientation sensors of the five sensor assemblies.

31. The robotic assembly of claim 30, wherein the circuit board further includes five rotor orientation sensors, each rotor orientation sensor being configured to monitor angular orientation of a rotor of a corresponding one of the five drive motors.

32. The robotic assembly of claim 25, wherein each of two of the output drive couplings that are furthest away from the insertion axis are used to actuate a corresponding finger of a two-finger surgical instrument, where the relative motions of the two fingers combine to provide both grip and yaw motions of a surgical end effector of the two-finger surgical instrument.