WO2025046445A1

WO2025046445A1 - Surgical robotic system with motor assembly

Info

Publication number: WO2025046445A1
Application number: PCT/IB2024/058289
Authority: WO
Inventors: Alexander Probst
Original assignee: Covidien LP
Current assignee: Covidien LP
Priority date: 2023-08-29
Filing date: 2024-08-26
Publication date: 2025-03-06
Anticipated expiration: 2026-02-28

Abstract

A surgical robotic system includes a robotic arm, a surgical instrument, and a motor assembly. The robotic arm includes a first arm section, a second arm section, and a joint interconnecting the first arm section and the second arm section. The motor assembly is disposed in operative engagement with the joint and is configured to effect movement of the first arm section relative to the second arm section. The motor assembly includes a stator defining a central aperture, a rotor disposed at least partially within the central aperture of the stator and being rotatable relative to the stator, and a sleeve radially surrounding the stator. The sleeve is electrically connected to the stator and is configured to absorb stray current.

Description

SURGICAL ROBOTIC SYSTEM WITH MOTOR ASSEMBLY

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63/579,338, filed August 29, 2023, the entire content of which is incorporated herein by reference.

BACKGROUND

[0002] Surgical robotic systems are currently being used in minimally invasive medical procedures. Some surgical robotic systems include a console supporting a surgical robotic arm and a surgical instrument having at least one end effector (e.g., forceps or a grasping tool) mounted to the robotic arm. The robotic arm and an instrument drive unit provide power to the surgical instrument for its operation and movement.

[0003] Frameless motor kits including a rotor and a stator may be used to actuate portions of the robotic arms and instrument drive units. However, some frameless motor kits create a parasitic capacitance, which may provide an unwanted alternating current path. The parasitic or stray currents may then flow through this path and cause unwanted radiated emissions.

SUMMARY

[0004] This disclosure relates to a surgical robotic system including a robotic arm, a surgical instrument coupled to a portion of the robotic arm, and a motor assembly. The robotic arm includes a first arm section, a second arm section, and a joint interconnecting the first arm section and the second arm section. The motor assembly is disposed in operative engagement with the joint and is configured to effect movement of the first arm section relative to the second arm section. The motor assembly includes a stator defining a central aperture, a rotor disposed at least partially within the central aperture of the stator and being rotatable relative to the stator, and a sleeve radially surrounding the stator. The sleeve is electrically connected to the stator and is configured to absorb stray current.

[0005] In disclosed embodiments, the sleeve is cylindrical.

[0006] In disclosed embodiments, the sleeve forms a complete ring around the stator. [0007] In disclosed embodiments, the stator includes a printed circuit board, and the sleeve is electrically connected to a dedicated terminal on the printed circuit board.

[0008] In disclosed embodiments, the sleeve is made out of sheet metal.

[0009] In disclosed embodiments, the sleeve is spaced from the stator a distance of between about 0.05mm and about 0.15mm.

[0010] In disclosed embodiments, the sleeve is in direct contact with the stator.

[0011] In disclosed embodiments, the surgical robotic system includes a housing at least partially surrounding the motor assembly.

[0012] In disclosed embodiments, the motor assembly is affixed to the joint.

[0013] In disclosed embodiments, the surgical robotic system also includes a control device disposed in communication with the motor assembly, and configured to regulate movement of the rotor relative to the stator.

[0014] In disclosed embodiments, the motor assembly includes a hollow core motor.

[0015] The disclosure also relates to a surgical system including a robotic arm engaged with a movable cart, and a motor assembly disposed in mechanical cooperation with the robotic arm. The motor assembly is configured to effect movement of a surgical instrument that is coupled to the robotic arm. The motor assembly includes a stator having a circuit board, a rotor rotatably disposed relative to the stator, a cylindrical sleeve radially surrounding the stator, and a cable connecting the sleeve and the circuit board of the stator.

[0016] In disclosed embodiments, the cable electrically connects the sleeve to a dedicated terminal on the circuit board of the stator.

[0017] In disclosed embodiments, the motor assembly is affixed to a joint on the robotic arm.

[0018] In disclosed embodiments, the sleeve is in direct contact with the stator.

[0019] In disclosed embodiments, the surgical system also includes a control device disposed in communication with motor assembly, and configured to regulate movement of the rotor relative to the stator. [0020] In disclosed embodiments, the motor assembly includes a hollow core motor.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Embodiments of the present disclosure are described herein with reference to the accompanying drawings, wherein:

[0022] FIG. 1 is a schematic illustration of a surgical system configured for use in accordance with the disclosure;

[0023] FIG. 2 is a perspective view of a portion of the surgical system of FIG. 1 including a robotic arm having an interface, where the robotic arm is disposed on a movable cart and is engaged with a surgical instrument, in accordance with embodiments of the present disclosure;

[0024] FIG. 3 is a perspective, assembly view of a motor assembly for use with the surgical system of FIG. 1 ; and

[0025] FIG. 4 is a perspective view of the motor assembly of FIG. 3.

DETAILED DESCRIPTION

[0026] Embodiments of the presently disclosed surgical robotic systems are described in detail with reference to the drawings, in which like reference numerals designate identical or corresponding elements in each of the several views. As used herein the term “distal” refers to that portion of the surgical adapter assembly, or component thereof, farther from the clinician (and generally closer to the patient), while the term “proximal” refers to that portion of the surgical adapter assembly, or component thereof, closer to the clinician (and generally farther from the patient).

[0027] As used herein, the term “clinician” refers to a doctor, nurse, or other care provider and may include support personnel. In the following description, well-known functions or construction are not described in detail to avoid obscuring the present disclosure in unnecessary detail.

[0028] With reference to FIG. 1, a surgical system, such as, for example, a robotic surgical system is shown generally as surgical system 100. The surgical system 100 includes an interface 150 (e.g., a sterile interface module), a plurality of robotic arms 200, a control device 300, and an operating console 350 coupled with the control device 300. The operating console 350 includes a display device 370, which is set up in particular to display three- dimensional images, and may include manual input devices 380, 382, by means of which a person (not shown), for example a surgeon, is able to telemanipulate the robotic arms 200 in a first operating mode, as known in principle to a person skilled in the art.

[0029] The surgical system 100 is configured for use on a patient “P” lying on a patient table “T” to be treated in a minimally invasive manner by means of at least one surgical instrument 500. The surgical system 100 may also include more than the two illustrated robotic arms 200, where the additional robotic arms are likewise connected to the control device 300 and are telemanipulatable by means of the operating console 350.

[0030] As discussed in further detail below, the robotic arms 200 and/or the interface 150 may be driven by electric drives or motor assemblies 600 that are connected to or in communication with the control device 300. The control device 300 (e.g., a computer) is set up to activate the motor assemblies 600, in particular by means of a computer program, in such a way that the robotic arms 200, instrument drive units 400 associated therewith, and thus the surgical instrument 500 (including the end effector 530) execute a desired movement according to a movement defined by means of the manual input devices 380, 382. The control device 300 may also be set up in such a way that it regulates the movement of the robotic arms 200 and/or of the motor assemblies 600.

[0031] Referring now to FIG. 2, where a single robotic arm 200 is shown coupled to a movable cart 280, the robotic arm 200 is composed of a plurality of arm sections 210, 220, 230, etc., where each adjacent section is connected through joints 215, 225, etc., respectively. The surgical system 100 may also include an instrument drive unit 400 engaged with the end of each robotic arm 200. The surgical instrument 500, or portions thereof, may be attached or configured to be attached to the instrument drive unit 400, in accordance with the present disclosure. As shown in Fig. 2, an elongated portion 510 of the surgical instrument 500 defines a longitudinal axis “X-X.” While the figures depict a particular type of surgical system (i.e., a robotic surgical system), the present disclosure encompasses other types of surgical systems (i.e., non-robotic surgical systems).

[0032] With reference to FIGS. 3 and 4, a motor assembly 600 is shown. The motor assembly 600, or more than one motor assembly 600, may be positioned at any reasonable location within the surgical system 100 to effectuate movement, for instance within the joints 215 and 225 connecting the arm sections 210, 220, 230. At least one motor assembly 600 may also be positioned within the instrument drive unit 400 to cause movement (e.g., rotation) and/or actuation of the surgical instrument 500.

[0033] In disclosed embodiments, the motor assembly 600 includes integrated AC motors. In embodiments, the motor of the motor assembly 600 may be any suitable type of electric motor such as a frameless motor, an AC brushless motor, a DC brushed motor, a DC brushless motor, a direct drive motor, a servo motor, a stepper motor, or the like. It is contemplated, and within the scope of the present disclosure, that the motor of the motor assembly 600 is in the form of a hollow core motor, or the like. Other types of motors are also contemplated. It is also contemplated that a plurality of motor assemblies 600 are interlinked, thereby providing an increased range of motion of the arm sections 210, 220, 230 of the robotic arms 200, and of the instrument drive unit 400, for example.

[0034] With continued reference to FIGS. 3 and 4, the motor assembly 600 includes a stator 620, a rotor 640, and a sleeve 660. The stator 620 includes a cylindrical frame 621 defining a central aperture 622 and defining a stator axis “Y-Y.” The stator 620 includes an inner wall 624, an outer wall 626, an upper surface 628 interconnecting the inner wall 624 and the outer wall 626, and a lower surface (hidden from view in the accompanying figures) interconnecting the inner wall 624 and the outer wall 626. The stator 620 also includes a plurality of magnets 630 spaced along the inner wall 624, and a circuit board 632 disposed on the upper surface 628. While circuit board 632 is shown and described as being disposed on the upper surface 628 of the stator 620, it is understood that the motor assembly 600 may be inverted where the circuit board 632 is located on a lower surface of the stator 620. The circuit board 632 includes at least two terminals including a first terminal 634 for connection to and/or communication with the control device 300, and a second terminal 636 for connection to the sleeve 660, as discussed below. In embodiments, the circuit board 632 includes four terminals, where three of the terminals are configured for connection to and/or communication with the control device 300, and where the fourth terminal is configured for connection to the sleeve 660.

[0035] Additionally, in the illustrated embodiment, the stator 620 includes a plurality of windings 638 positioned along the outer wall 626. The windings 638 are used to deliver current to the plurality of magnets 630. [0036] The stator 620 is non-rotatably secured to a housing or carriage 670 (see FIG. 2) disposed on part of the robotic system 100, such as the joint 215 and/or the joint 225 of the robotic arm 200, for instance.

[0037] The rotor 640 is disposed within the central aperture 622 of the stator 620 and is rotatable about the stator axis “Y-Y” relative to the stator 620. The rotor 640 includes a cylindrical frame 641, and includes an outer wall 646 including a plurality of magnets 650 spaced along the outer wall 646.

[0038] The stator 620 may be configured to receive an electric current from a power source (not explicitly shown) to produce a rotating magnetic field that drives a rotation of the rotor 640 relative to the stator 620.

[0039] The rotor 640 may be configured as a permanent magnetic, an electromagnet, or any other suitable conductor.

[0040] With continued reference to FIGS. 3 and 4, the sleeve 660 is in the form of a cylindrical sleeve that radially surrounds the stator 620. The sleeve 660 is non-rotatably fixed to the stator 620, and includes a wire or cable 664 connecting the sleeve 660 to the stator 620. More particularly, the cable 664 interconnects the sleeve 660 with the second terminal 636 (e.g., a dedicated terminal) on the circuit board 632 of the stator 620. In embodiments, the cable 664 is soldered to the sleeve 660 and/or to the second terminal 636.

[0041] The sleeve 660 is made from a thin sheet of metal and may be constructed as a foil surrounding the stator 620. More particularly, the sleeve 660 can be made from any material that is suitable to form an electrode of a capacitor, such as sheet metal, copper, aluminum, etc. Additionally, while the sleeve 660 is illustrated as a cylindrical ring, the sleeve 600 may be any regular or irregular shape. Moreover, the shape of the sleeve 660 may be flexible or pliable in instances when the sleeve 660 includes a foil-like malleability where the sleeve 660 can conform to the shape of the stator 620. Further, the sleeve 660 may include a uniform wall thickness, or the wall thickness of the sleeve 660 may not be uniform. In embodiments, the wall thickness of the sleeve 660 can be thin (e.g., foil-like), which would only minimally increase the diameter of the stator 620 (or the stator 620/ sleeve 660 combination), thereby allowing the various design parameters of the stator 620 to remain unchanged or not significantly changed. [0042] In embodiments, the sleeve 660 is in contact with the stator 620 or with portions of the stator 620. In other embodiments, the sleeve 660 is spaced from the stator 620 a sufficient distance to maintain sufficient dielectric strength. For instance, the sleeve 660 may be spaced between about 0.05mm and about 0.15mm (e.g., equal to about 0.1mm) from the stator 620.

[0043] In typical motor assemblies without the disclosed sleeve 660, a parasitic capacitance is created between the carriage that houses the motor assembly and the stator of the motor assembly. This capacitance provides an unwanted AC current path that is sometimes routed in ineffective and/or inefficient ways in typical motor assemblies. The parasitic or stray currents that flow through this path can cause unwanted radiated emissions. Some product testing limits the amount of such radiated emissions that is permissible.

[0044] In the motor assembly 600 of the present disclosure, the sleeve 660 and its connection to the second terminal 636 of the stator 620 provide a path for the parasitic or stray current to be directed back to its source (e.g., the carriage 670/stator 620 engagement) such that the sleeve 660 absorbs the parasitic or stray current. This relatively short path that transmits the parasitic or stray current back to its source improves emissions that are radiated from the motor assembly 600.

[0045] Additionally, while the motor assembly 600 is described in connection with a surgical system (e.g., a robotic surgical system), the disclosed motor assembly 600 is usable in connection with other types of electro-mechanical systems without departing from the scope of the present disclosure. Moreover, the motor assembly 600 including the sleeve 660 can be used in a wide variety of industrial applications that utilize an electric motor such as a frameless motor kit, for instance.

[0046] The present disclosure also includes multiple motor assemblies 600 used together, such as in a stacked configuration. An example of stacked motor assemblies is disclosed in U.S. Patent Application Publication No. 2021/0212786, filed on February 23, 2021, the entire content of which is incorporated herein by reference.

[0047] The various embodiments disclosed herein may also be configured to work with robotic surgical systems and what is commonly referred to as “Telesurgery.” Such systems employ various robotic elements to assist the surgeon in the operating theater and allow remote operation (or partial remote operation) of surgical instrumentation. Various robotic arms, gears, cams, pulleys, electric and mechanical motors, etc. may be employed for this purpose and may be designed with a robotic surgical system to assist the surgeon during the course of an operation or treatment. Such robotic systems may include, remotely steerable systems, automatically flexible surgical systems, remotely flexible surgical systems, remotely articulating surgical systems, wireless surgical systems, modular or selectively configurable remotely operated surgical systems, etc.

[0048] The robotic surgical systems may be employed with one or more consoles that are next to the operating theater or located in a remote location. In this instance, one team of surgeons or nurses may prepare the patient for surgery and configure the robotic surgical system with one or more of the instruments disclosed herein while another surgeon (or group of surgeons) remotely control the instruments via the robotic surgical system. As can be appreciated, a highly skilled surgeon may perform multiple operations in multiple locations without leaving his/her remote console which can be both economically advantageous and a benefit to the patient or a series of patients.

[0049] The robotic arms of the surgical system are typically coupled to a pair of master handles by a controller. The handles can be moved by the surgeon to produce a corresponding movement of the working ends of any type of surgical instrument (e.g., end effectors, graspers, knifes, scissors, etc.) which may complement the use of one or more of the embodiments described herein. The movement of the master handles may be scaled so that the working ends have a corresponding movement that is different, smaller or larger, than the movement performed by the operating hands of the surgeon. The scale factor or gearing ratio may be adjustable so that the operator can control the resolution of the working ends of the surgical instrument(s).

[0050] The master handles may include various sensors to provide feedback to the surgeon relating to various tissue parameters or conditions, e.g., tissue resistance due to manipulation, cutting or otherwise treating, pressure by the instrument onto the tissue, tissue temperature, tissue impedance, etc. As can be appreciated, such sensors provide the surgeon with enhanced tactile feedback simulating actual operating conditions. The master handles may also include a variety of different actuators for delicate tissue manipulation or treatment further enhancing the surgeon’s ability to mimic actual operating conditions. [0051] Reference may be made to U.S. Patent No. 8,828,023, entitled “Medical Workstation,” the entire content of which is incorporated herein by reference, for a detailed discussion of the construction and operation of surgical system 2000.

[0052] It should be understood that the foregoing description is only illustrative of the disclosure. Various alternatives and modifications can be devised by those skilled in the art without departing from the disclosure. Accordingly, this disclosure is intended to embrace all such alternatives, modifications and variances. The embodiments described with reference to the attached drawing figures are presented only to demonstrate certain examples of the disclosure. Other elements, steps, methods and techniques that are insubstantially different from those described above and/or in the appended claims are also intended to be within the scope of the disclosure.

Claims

WHAT IS CLAIMED IS:

1. A surgical robotic system, comprising: a robotic arm including a first arm section, a second arm section, and a joint interconnecting the first arm section and the second arm section; a surgical instrument coupled to a portion of the robotic arm; and a motor assembly disposed in operative engagement with the joint and configured to effect movement of the first arm section relative to the second arm section, the motor assembly including a stator defining a central aperture, a rotor disposed at least partially within the central aperture of the stator and being rotatable relative to the stator, and a sleeve radially surrounding the stator, the sleeve being electrically connected to the stator and configured to absorb stray current.

2. The surgical robotic system according to claim 1, wherein the sleeve is cylindrical.

3. The surgical robotic system according to claim 1, wherein the sleeve forms a complete ring around the stator.

4. The surgical robotic system according to claim 1, wherein the stator includes a printed circuit board, and the sleeve is electrically connected to a dedicated terminal on the printed circuit board.

5. The surgical robotic system according to claim 1, wherein the sleeve is made out of sheet metal.

6. The surgical robotic system according to claim 1, wherein the sleeve is spaced from the stator a distance of between about 0.05mm and about 0.15mm.

7. The surgical robotic system according to claim 1, wherein the sleeve is in direct contact with the stator.

8. The surgical robotic system according to claim 1, further including a housing at least partially surrounding the motor assembly.

9. The surgical robotic system according to claim 1, wherein the motor assembly is affixed to the joint.

10. The surgical robotic system according to claim 1, further including a control device disposed in communication with the motor assembly, and configured to regulate movement of the rotor relative to the stator.

11. The surgical robotic system according to claim 1, wherein the motor assembly includes a hollow core motor.

12. A surgical system, comprising: a robotic arm engaged with a movable cart; and a motor assembly disposed in mechanical cooperation with the robotic arm and configured to effect movement of a surgical instrument that is coupled to the robotic arm, the motor assembly including a stator having a circuit board, a rotor rotatably disposed relative to the stator, a cylindrical sleeve radially surrounding the stator, and a cable connecting the sleeve and the circuit board of the stator.

13. The surgical system according to claim 12, wherein the cable electrically connects the sleeve to a dedicated terminal on the circuit board of the stator.

14. The surgical system according to claim 12, wherein the motor assembly is affixed to a joint on the robotic arm.

15. The surgical system according to claim 12, wherein the sleeve is in direct contact with the stator.

16. The surgical system according to claim 12, further including a control device disposed in communication with the motor assembly, and configured to regulate movement of the rotor relative to the stator.

17. The surgical system according to claim 12, wherein the motor assembly includes a hollow core motor.