Systems and methods for implementing multi-turn rotation concepts in actuator mechanisms of surgical robotic arms

Abstract

A surgical robot arm of a surgical robot system including articulating segments mechanically and operably coupled together to form one or more joints, the articulating segment including a rotational actuation mechanism having a male segment assembly having one or more structural components rotatable about its longitudinal axis by one or more cables and rotatable to greater than 360 degrees, and a female segment assembly sized and configured to seat and operably couple with the male segment assembly.

Description

[Technical field]

[0001] The present invention is directed to minimally invasive surgical devices and related methods, and more particularly to robotic surgical systems that are inserted into a patient to perform selected surgical procedures on the patient. [Background technology]

[0002] Since its introduction in the early 1990s, the field of minimally invasive surgery has expanded rapidly. Minimally invasive surgery greatly improves patient outcomes, but this improvement comes at the expense of the surgeon's ability to operate with precision and ease. During laparoscopic surgery, surgeons must insert laparoscopic instruments through small incisions in the patient's abdominal wall. The nature of the insertion of the instruments through the abdominal wall constrains the motion of the laparoscopic instruments as they cannot be moved side to side without damage to the abdominal wall. Standard laparoscopic instruments are limited to four axes of motion. These four axes of motion are the movement of the instrument in and out of the trocar (axis 1), the rotation of the instrument within the trocar (axis 2), and the angular movement of the trocar in two planes while maintaining a pivot point for the entry of the trocar into the abdominal cavity (axis 3 and 4). For over 20 years, the majority of minimally invasive surgical procedures have been performed with only these four degrees of motion.

[0003] Existing robotic surgical devices have attempted to solve many of these problems. Some existing robotic surgical devices replicate non-robotic laparoscopic surgery with additional degrees of freedom at the end of the instrument. However, even with many costly modifications to the surgical procedure, existing robotic surgical devices have failed to provide improved patient outcomes in the majority of procedures in which they are used. In addition, existing robotic devices create an increased separation between the surgeon and the surgical end effector. This increased separation causes injuries due to the surgeon's misinterpretation of the motions and forces applied by the robotic device. Because the multiple degrees of freedom of many existing robotic devices are unfamiliar to human operators, such as surgeons, surgeons typically undergo extensive training on a robotic simulator before operating on a patient to minimize the possibility of inadvertently causing injury to the patient. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent No. 10,285,765 [Patent Document 2] US Patent Application Publication No. 2019 / 0076199 [Patent Document 3] US Patent Application Publication No. 2018 / 0221102 Summary of the Invention [Problem to be solved by the invention]

[0005] To control existing robotic devices, the surgeon sits at a console and controls manipulators with his hands and feet. In addition, the robotic camera remains in a semi-fixed position and is moved by combined foot and hand movements from the surgeon. These semi-fixed cameras with limited field of view make visualization of the surgical field difficult.

[0006] Other robotic devices have two robotic manipulators inserted through a single incision. These devices often reduce the number of incisions required to a single incision at the umbilicus. However, existing single incision robotic devices have significant drawbacks that stem from their actuator design. Existing single incision robotic devices include servo motors, encoders, gearboxes, and all other actuation devices within the in vivo robot. This decision to include the motors and gearboxes within the patient's body has resulted in large robots with limited capabilities. Such large robots must be inserted through large incisions, thus increasing the risk of hernias, the risk of infection, pain, and general morbidity. Furthermore, the size of these devices is unlikely to be significantly reduced so far by the inclusion of motors, gears, etc. within the in vivo devices. This increase in incision size significantly increases the damage to the patient and greatly reduces the utility of existing devices.

[0007] Existing single incision devices also have limited degrees of freedom, some of which are non-intuitive to humans, such as extending the arm during the procedure, requiring a user interface that forces the surgeon to perform similar non-intuitive learning movements as existing multi-incision devices.

[0008] In previous Vicarious Surgical robotic systems, the robotic arm has articulating segments or sections and end effectors that can be manipulated and moved in multiple degrees of freedom using selected mechanical arrangements. Specifically, the robotic arm can employ pulleys and associated cables or wires that traverse along an elongated shaft and can connect various sections of the robotic arm. A drive assembly coupled to the cables can be used to provide actuation forces to the cables to actuate and / or manipulate the arm sections and end effectors of the instruments. The drive assembly can be mounted on the robotic arm or coupled to another portion of the surgical robotic system that is controlled by the surgeon to move the robotic arm in various degrees of freedom.

[0009] Additionally, any rotating joint of a robotic arm has a limited range of motion determined by the amount of drive cable that can be wound, or usually by the amount of extra slack in the electrical wires that typically pass through each joint of a robotic arm to carry signals such as joint angle measurements back to the controller and surgeon. When the rotation of the various joints reaches or exceeds its mechanical limits, there is typically a mechanical failure of the electrical wires and / or drive cables. [Means for solving the problem]

[0010] The present invention is directed to a cable-driven rotary joint of a robotic arm of a surgical robotic system that is capable of multiple rotations (e.g., at least two rotations in either direction) with hard stops formed at each end of the joint travel, but at the same time has the ability to precisely determine the number of rotations or turns of the joint via a series of sensors, as well as the specific angle of rotation of the joint during initiation and use of the surgical robotic system. Thus, the revolute joint is capable of rotating about a longitudinal axis to an extent of greater than 360 degrees.

[0011] The present invention is therefore directed to a surgical robotic system employing a robotic arm having an articulating segment including a male segment assembly seated within and rotatable relative to a female segment assembly. The articulating segment may be located at and form part of a joint of the robotic arm, such as a shoulder joint, an elbow joint, or a wrist joint. The male segment assembly includes a structure including a groove, such as a helical or spiral groove, formed on an outer surface. The female segment assembly includes a structure including a slot that mounts a shuttle assembly including a magnet. The shuttle assembly moves linearly or axially within the slot as the male segment assembly rotates. The position of the shuttle assembly and the sensing magnet may be determined by a series of sensors mounted relative to the slot and the shuttle assembly to sense the position of the shuttle magnet and the sensing magnet. The surgical robotic system may then determine the number of turns of the articulating segment and the rotation angle of the articulating segment (partial turn position) based on the position of the shuttle and the sensing magnet.

[0012] The present invention is directed to a surgical robot arm of a surgical robot system having a plurality of articulating segments mechanically and operably coupled together to form one or more joints. The articulating segments can include a rotational actuation mechanism having a male segment assembly rotatable about its longitudinal axis by one or more cables and having one or more structural components rotatable to greater than 360 degrees, and a female segment assembly sized and configured to seat and operably couple with the male segment assembly.

[0013] The female segment assembly includes a linear slot, and the structural component can include a groove, such as a helical groove, and the robotic arm further includes a shuttle assembly having a shuttle element sized and configured to contact the groove such that the shuttle element moves linearly within the slot as the male segment component rotates. The robotic arm can also include a first sensor assembly configured to sense a linear position of the shuttle element within the slot and generate first sensor data, according to one embodiment. The first sensor data is processed to determine one or more of a number of turns of the one or more structural components of the male segment assembly and a rotational angular position of the one or more structural components. The robotic arm can include an optional second sensor assembly configured to sense a rotational angular position of the structural component of the male segment assembly and generate second sensor data. The first sensor data and the second sensor data can be processed by a computing unit to determine a rotational position of the joint.

[0014] According to another embodiment of the present invention, a surgical robotic arm can include a sensor assembly coupled to either the male segment assembly or the female segment assembly for sensing a rotational position of a structural component of the male segment assembly. The sensing assembly can include a first plurality of sensors for generating first sensor data indicative of a number of rotations of the one or more structural components of the male segment assembly and a second plurality of sensors for generating second sensor data indicative of a rotational angular position of the one or more structural components of the male segment assembly. The first sensor data and the second sensor data can be processed to determine a rotational position of the structural component of the male segment assembly.

[0015] The structural component of the male segment assembly can have a groove formed therein for seating a shuttle element configured to travel along the path. The groove has a first hard stop formed at one end of the path and a second hard stop formed at an opposite end of the path, and the shuttle element is movable within or along the groove greater than 360 degrees as the male segment assembly rotates. The first hard stop and the second hard stop determine a maximum number of rotations of one or more structural components of the male segment assembly. According to one embodiment, the shuttle element can include a bearing element and the groove can be a circular groove or a spiral groove.

[0016] According to one embodiment, the groove is a helical groove and the female segment assembly has a slot formed therein configured and positioned to communicate with at least a portion of the groove. A shuttle assembly seated within the slot may be provided, which may include a shuttle element, a first magnet coupled to one end of the shuttle element, and a bearing element coupled to an opposite end of the shuttle element for contacting the groove. The shuttle assembly is configured to move linearly within the slot. The robotic arm may include a first plurality of sensors configured to sense a position of the first magnet within the slot and generate in response to first sensor data. The robotic arm may optionally include a second magnet coupled to a structural component of the male segment assembly and rotatable therewith. An optional second plurality of sensors may be configured to sense a rotational angular position of the second magnet and generate second sensor data.

[0017] The one or more structural components of the male segment may include a rotating shaft element having a body with an outer surface and an engagement member coupled to the outer surface of the rotating shaft element. The engagement member has an outer surface with a groove formed therein. The female segment assembly may include an outer housing element disposed about at least a portion of the engagement element and having a slot formed therein exposing at least a portion of the groove. The female segment assembly may further include an optional abutment element for axially separating the engagement element from a bearing element disposed about a portion of the outer surface of the rotating shaft element.

[0018] The present invention is also directed to a surgical robot arm of a surgical robot system including a plurality of articulating segments mechanically and operably coupled together. The articulating segments can include a rotational actuation mechanism including a male segment assembly having a rotating shaft element with a body having an outer surface, and an engagement element coupled to the outer surface of the rotating shaft member and having a helical groove formed therein. The rotational actuation mechanism also includes a female segment assembly having an outer housing element disposed about at least a portion of the engagement element and having a slot formed therein exposing at least a portion of the groove. The robot arm can further include a shuttle assembly mounted within a slot formed in the outer housing element such that a portion of the shuttle assembly seats within the groove of the engagement element. The male segment assembly is disposed within the female segment assembly and is rotatable relative thereto about a longitudinal axis, rotatable to an extent of greater than about 360 degrees.

[0019] The robotic arm of the present invention also optionally includes one or more of a bearing element disposed about a portion of an outer surface of the rotating shaft element, a flange element formed at one end of the rotating shaft element, and a skirt element formed at one end of the engaging element. The female segment assembly can optionally include an abutment element positioned axially of the skirt element of the engaging element and the bearing element for axially separating the engaging element from the bearing element.

[0020] The robotic arm of the present invention can also include a first sensor assembly configured to sense the position of the shuttle assembly in the slot and generate first sensor data. The first sensor data can be processed, for example, by a computing unit to determine the number of turns of the male segment assembly and / or the rotational angular position of the male segment assembly. The surgical robotic arm of the present invention can also include an optional second sensor assembly configured to sense the rotational angular position of the male segment assembly and generate second sensor data. The computing unit can be used to process the first sensor data and the second sensor data to determine the rotational position of the joint.

[0021] According to another embodiment, the surgical robotic arm can include a sensor assembly coupled to the male segment assembly or the female segment assembly for sensing a rotational position of the male segment assembly. The sensing assembly can include a first plurality of sensors for generating first sensor data indicative of a number of rotations of the male segment assembly and a second plurality of sensors for generating second sensor data indicative of a rotational angular position of the male segment assembly. The first sensor data and the second sensor data can be processed to determine the rotational position of the male segment assembly.

[0022] The groove has a first hard stop formed at one end and a second hard stop formed at an opposing end. The shuttle assembly is movable in the groove to greater than 360 degrees upon rotation of the male segment assembly, the first hard stop and the second hard stop determining a maximum number of rotations of one or more structural components of the male segment assembly. The shuttle assembly can include a bearing element sized and configured to communicate with the groove, a shuttle element having a first end with a recess formed therein for seating a first portion of the bearing element, and a shuttle magnet coupled to a second opposing end of the shuttle element. A first plurality of sensors can be associated with a slot formed in the outer housing element for sensing a linear position of the shuttle magnet within the slot and generating first sensor data. The first plurality of sensors can include a first slot sensor associated with one end of the slot and a second slot sensor associated with an opposing end of the slot, the first sensor data being indicative of a number of rotations of the male segment assembly and can be processed to determine a rotational angular position of the male segment assembly.

[0023] The surgical robotic arm can also include an optional annular sensing magnet rotatably coupled to the rotating shaft element or the engaging element of the male segment assembly. The arm can include an optional second plurality of sensors circumferentially disposed about the annular sensing magnet for sensing a rotational angular position of the annular sensing magnet and generating second sensor data indicative of the rotational angular position of the male segment assembly.

[0024] The present invention is also directed to a method for rotating an articulated portion of a surgical robot arm of a surgical robot system, the method including: providing a robot arm having one or more articulating segments mechanically and operably coupled together to form a joint, the articulating segment including a male segment assembly having one or more rotatable structural components and a female segment assembly sized and configured for seating the male segment assembly; rotating the structural component of the male segment assembly with one or more cables about its longitudinal axis, the structural component being rotatable to a degree of greater than about 360 degrees; and sensing a rotational position of the structural component of the male segment assembly with a sensor assembly coupled to one or more of the male segment assembly and the female segment assembly.

[0025] The method may also include generating first sensor data with the sensor assembly and determining a number of rotations of the structural component of the male segment assembly from the first sensor data. Additionally, the method may determine a rotational angular position of the structural component of the male segment assembly from the first sensor data.

[0026] The present invention may also include generating first sensor data with a sensor assembly, determining a number of rotations of a structural component of the male segment assembly from the first sensor data, generating second sensor data with the sensor assembly, and determining a rotational angular position of the structural component of the male segment assembly from the second sensor data. The first sensor data and the second sensor data may be processed to determine the rotational position.

[0027] The method of the present invention may further include providing a groove in a structural component of the male segment assembly for seating a shuttle element configured to travel along a path, the groove having a first hard stop formed at one end of the path and a second hard stop formed at an opposite end of the path, and moving the shuttle element in greater than 360 degrees upon rotation of the structural component. The first hard stop and the second hard stop may determine a maximum number of rotations of one or more structural components of the male segment assembly. The method also includes associating a first magnet with the shuttle element and sensing a position of the first magnet in the groove with a sensor assembly. An optional second magnet may be coupled to the structural member of the male segment assembly, and a rotational angular position of the second magnet may be determined by the sensor assembly.

[0028] These and other features and advantages of the present invention will be more fully understood by reference to the following detailed description in conjunction with the accompanying drawings, in which like reference characters refer to like elements throughout the various views, the drawings illustrate the principles of the invention and, although not to scale, show relative dimensions. [Brief description of the drawings]

[0029] [Figure 1] FIG. 1 is a schematic diagram of a surgical robot system of the present invention. [Figure 2A] FIG. 2 is a perspective view of a robot arm of a robot unit in accordance with the teachings of the present invention. [Figure 2B] FIG. 2 is a perspective view of a robot arm of a robot unit in accordance with the teachings of the present invention. [Figure 3A] FIG. 1 is a schematic partial cross-sectional view of an articulating segment (rotary actuator section) of a robotic arm, showing, for example, a male segment assembly, in accordance with the teachings of the present invention. [Figure 3B] 1 is a schematic partial cross-sectional view of an articulation segment showing, for example, a female segment assembly in accordance with the teachings of the present invention; [Figure 4]FIG. 2 is a schematic partial cross-sectional perspective view of an articulating segment of a robotic arm showing a shuttle assembly employed therein in accordance with the teachings of the present invention; [Figure 5A] FIG. 2 is a schematic partial cross-sectional perspective view of an articulating segment of a robotic arm showing the shuttle assembly disposed in a first hard stop position in accordance with the teachings of the present invention. [Figure 5B] FIG. 2 is a partial cross-sectional view of an articulating segment of a robotic arm showing the shuttle assembly disposed in a first hard stop position in accordance with the teachings of the present invention. [Figure 6] FIG. 1 is a schematic partial cross-sectional perspective view of an articulating segment of a robotic arm showing the shuttle assembly position after one full rotation of the male segment assembly in accordance with the teachings of the present invention. [Figure 7] FIG. 1 is a schematic partial cross-sectional perspective view of an articulating segment of a robotic arm showing the shuttle assembly position after two full rotations of the male segment assembly in accordance with the teachings of the present invention. [Figure 8] FIG. 1 is a schematic partial cross-sectional perspective view of the rotational actuator section of the robotic arm showing the shuttle assembly position after three full rotations of the male segment assembly in accordance with the teachings of the present invention. [Figure 9] FIG. 1 is a schematic partial cross-sectional perspective view of a rotational actuator section of a robotic arm showing a shuttle assembly disposed in a second hard stop position after four full rotations of a male segment assembly in accordance with the teachings of the present invention. [Figure 10] 1 is a schematic partial cross-sectional view of a rotational actuator section of a robotic arm showing incremental or sensing magnetic elements employed therein for determining the rotational position of an articulation segment in accordance with the teachings of the present invention. [Figure 11] 1 is a schematic partial cross-sectional view of an articulating segment of a robotic arm showing incremental magnetic elements and associated printed circuit boards having sensors in accordance with the teachings of the present invention; [Figure 12] FIG. 2 is a perspective view of a printed circuit board and associated sensors utilized by an articulating segment of a robotic arm in accordance with the teachings of the present invention. [Figure 13A] 1 is a simplified partial cross-sectional view of a portion of an articulation segment illustrating the position of a shuttle assembly within a slot formed in a female segment assembly in accordance with the teachings of the present invention. FIG. [Figure 13B] FIG. 13 is a schematic partial top view of a portion of an articulation segment illustrating the position of a shuttle assembly within a slot formed in the female segment assembly in accordance with the teachings of the present invention; [Figure 14A] FIG. 11 is a schematic, pictorial, partial cross-sectional view of a portion of an articulation segment showing the position of a second embodiment of a shuttle assembly within a slot formed in the female segment assembly, illustrating the use of a single sensor in accordance with the teachings of the present invention. [Figure 14B] FIG. 13 is a schematic, pictorial, partial top view of a portion of an articulation segment illustrating the position of a second embodiment of a shuttle assembly within a slot formed in the female segment assembly, illustrating the use of a single sensor in accordance with the teachings of the present invention. [Figure 15] FIG. 11 is a partial perspective view of a second embodiment of the multi-turn concept of the present invention. [Figure 16] 1 illustrates yet another embodiment of the multi-turn concept of the present invention. [Figure 17] 1 is a schematic cross-sectional view illustrating the path of movement of a ball bearing within a groove as a male segment assembly rotates in accordance with the teachings of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] In the following description, numerous specific details are described with respect to the systems and methods of the present invention, and the environments in which the systems and methods may operate, to provide a thorough understanding of the disclosed subject matter. However, it will be apparent to those skilled in the art that the disclosed subject matter may be practiced without such specific details, and that certain features well known in the art have not been described in detail to avoid complexity and enhance clarity of the disclosed subject matter. Additionally, any examples provided below are merely illustrative and should not be construed in a limiting manner, and it will be understood that other systems, apparatuses, and / or methods may be used to implement or accomplish the teachings of the present invention and are considered to be within the scope of the present invention.

[0031] Although the systems and methods of the present invention may be designed for use with one or more surgical robotic systems used as part of a virtual reality surgical system, the surgical robotic systems of the present invention may be used in connection with any type of surgical system including, for example, robotic surgical systems, linear stick surgical systems, and laparoscopic systems. In addition, the systems of the present invention may be used in other non-surgical systems where a user requires access to a myriad of information while controlling a device or apparatus.

[0032] The surgical robotic system 10 of the present invention employs a robotic subsystem 20 including a robotic unit 50 that can be inserted into a patient via a trocar through a single incision point or site. The robotic unit 50 is small enough to be deployed in vivo at a surgical site and sufficiently maneuverable when inserted to be movable within the body to perform various surgical procedures at multiple different points or sites. The robotic unit 50 includes multiple separate robotic arms that can be deployed within the patient along different or separate axes. Additionally, a surgical camera assembly can also be deployed along a separate axis and form part of the robotic unit 50. Thus, the robotic unit 50 employs multiple different components, such as a pair of robotic arms and a surgical or robotic camera assembly, each of which can be deployed along a different axis and can be separately steerable, steerable, and movable. A robotic arm and a camera assembly that can be disposed along separate steerable axes is referred to herein as a split-arm (SA) architecture. The SA architecture is designed to simplify and increase efficiency of insertion of robotic surgical instruments through a single trocar at a single insertion site while also assisting in deployment of the surgical instruments to a surgery-ready state and subsequent removal of the surgical instruments through the trocar. As an example, surgical instruments may be inserted through the trocar to access a patient's abdominal cavity and perform surgery in vivo. In some embodiments, a variety of surgical instruments may be utilized, including, but not limited to, robotic surgical instruments and other surgical instruments known in the art.

[0033] The systems and methods disclosed herein may be incorporated into and utilized with, for example, the robotic surgical devices and associated systems disclosed in U.S. Patent No. 5,399,623 and PCT Patent Application No. PCT / US20 / 39203, and / or the camera assemblies and systems disclosed in U.S. Patent No. 5,399,623, the entire contents and teachings of which are incorporated herein by reference. The robotic unit 50 forming part of the present invention may form part of a robotic subsystem 20 which in turn forms part of a surgical robotic system 10 including a surgeon or user workstation including suitable sensor and display units and a robotic support system (RSS) for interacting with and supporting the robotic unit of the present invention. The robotic subsystem 20 may, in one embodiment, include portions of the RSS, such as, for example, motor assemblies and associated mechanical linkages, and the surgical robotic unit 50 may include one or more robotic arms and one or more camera assemblies. The surgical robotic unit 50 may provide multiple degrees of freedom such that the robotic unit may be maneuvered to a single position or multiple different positions within a patient. In one embodiment, the robotic support system may be mounted directly to the operating table or to the floor or ceiling within the operating room. In another embodiment, attachment is accomplished by a variety of fastening means, including but not limited to clamps, screws, or combinations thereof. In yet other embodiments, the structure may be freestanding, transportable, or mobile. The robotic support system can mount a motor assembly that is coupled to the surgical robotic unit and can include gears, motors, drive trains, electronics, etc., for powering the components of the surgical robotic unit.

[0034] The robotic arm and camera assembly are capable of multiple degrees of freedom of movement. According to one practice, when the robotic arm and camera assembly are inserted into a patient through a trocar, they are capable of moving in at least axial, yaw, pitch, and roll directions. The robotic arm assembly is designed to incorporate and utilize a multi-degree of freedom of movement robotic arm having an end effector region attached to its distal end that corresponds to a user's wrist and hand region or joint. In other embodiments, the working end (e.g., end effector end) of the robotic arm is designed to incorporate and utilize other robotic surgical instruments, such as, for example, the surgical instruments described in U.S. Patent No. 6,399,333, the contents of which are incorporated herein by reference.

[0035] 1 is a schematic block diagram of a surgical robotic system 10 in accordance with the teachings of the present invention. The system 10 includes a display unit or unit 12, a virtual reality (VR) computing unit 14, a sensing and tracking unit 16, a computing unit 18, and a robotic subsystem 20. The display unit 12 can be any selected type of display for displaying information, images, or videos generated by the VR computing unit 14, the computing unit 18, and / or the robotic subsystem 20. The display unit 12 can include or form part of, for example, a head mounted display (HMD), a screen or display, a three-dimensional (3D) screen, etc. The display unit can form part of a surgeon's or user's workstation.

[0036] The display unit 12 may also include an optional sensor and tracking unit 16A, such as may be found in a commercially available head mounted display. The sensing and tracking units 16 and 16A may include one or more sensors or detectors coupled to a user of the system, such as, for example, a nurse or a surgeon. The sensors may be coupled to the user's arms, and if a head mounted display is not used, additional sensors may be coupled to the user's head and / or neck regions. The sensors in this arrangement are represented by the sensor and tracking unit 16. If the user uses a head mounted display, eye, head and / or neck sensors and associated tracking technology may be incorporated or used within that device and thus form part of the optional sensor and tracking unit 16A. The sensors of the sensor and tracking unit 16 coupled to the surgeon's arms may preferably be coupled to selected regions of the arm, such as, for example, the shoulder region, elbow region, wrist or hand region, and, if desired, the fingers. According to one practice, the sensors from part of a pair of hand controllers operated by the surgeon. The sensors generate position data indicative of the position of the selected part of the user. The sensing and tracking unit 16 and / or 16A may be utilized to control the movement of the camera assembly 44 and the robotic arm 42 of the robotic subsystem 20. The position data 34 generated by the sensors of the sensor and tracking unit 16 may be communicated to the computing unit 18 for processing by the processor 22. The computing unit 20 may determine or calculate the position and / or orientation of each part of the surgeon's arm from the position data 34 and communicate this data to the robotic subsystem 20. According to an alternative embodiment, the sensing and tracking unit 16 may use sensors coupled to the surgeon's torso or any other body part. Furthermore, the sensing and tracking unit 16 may use, in addition to the sensors, an inertial momentum unit (IMU) having, for example, an accelerometer, a gyroscope, a magnetometer, and a motion processor. The addition of a magnetometer is standard practice in the field, since a magnetic orientation can reduce sensor drift around the vertical axis.Alternative embodiments include sensors located within surgical materials such as gloves, surgical scrubs, or surgical gowns. The sensors may be reusable or disposable. Additionally, the sensors may be disposed external to the user, such as in a fixed location in a room such as an operating room. The external sensors may generate external data 36 that may be processed by the computing unit and thus used by the system 10. In other embodiments, there are sensors located on mechanical linkages that are operated by the user. The sensors generate signals that serve as inputs that are processed by the computing unit. According to another embodiment, when the display unit 12 is a head mounted display with an associated sensor and tracking unit 16A, the device generates tracking and position data 34A that is received and processed by the VR computing unit 14. Additionally, the sensor and tracking unit 16 includes a hand controller, if desired. The display, sensing and tracking unit, VR computing unit, etc. may form part of the surgeon or a remote workstation.

[0037] In embodiments where the display unit is an HMD, the display unit 12 may be, for example, a virtual reality head mounted display such as Oculus Rift, Varjo VR-1, or HTC Vive Pro Eye. The HMD may provide the user with a display unit that is coupled or attached to the user's head, lenses that allow for a focused view of the display unit, and a sensor and / or tracking system 16A that provides tracking of the position and orientation of the display unit. The position and orientation sensor system may include, for example, accelerometers, gyroscopes, magnetometers, motion processors, infrared tracking, eye tracking, computer vision, emitting and sensing alternating magnetic fields, and any other method of tracking at least one of position and orientation, or any combination thereof. As is known, the HMD may provide image data from a camera assembly 44 to the right and left eyes of the surgeon. To maintain a virtual reality experience for the surgeon, the sensor system may track the position and orientation of the surgeon's head and then relay the data to the VR computing unit 14 and, if desired, to the computing unit 18. The computing unit 18 can further adjust the pan and tilt of the robot's camera assembly 44 to follow the movements of the user's head.

[0038] When associated with an HMD, such as associated with the display unit 12 and / or tracking unit 16A, sensor or position data 34A generated by the sensors may be communicated to the computing unit 18, either directly or via the VR computing unit 14. Similarly, tracking and position data 34 generated by other sensors in the system, such as the sensing and tracking unit 16, which may be associated with the user's arms and hands, may be communicated to the computing unit 18. The tracking and position data 34, 34A may be processed by the processor 22 and stored, for example, in the storage unit 24. The tracking and position data 34, 34A may also be used by the control unit 26, which may responsively generate control signals to control the movement of one or more portions of the robotic subsystem 20. The surgical robotic system 10 may include a surgeon or user workstation, a robotic support system (RSS), and a robotic subsystem 20, which may include an implantable robotic unit 50 including a motor unit 40 and one or more robotic arms 42 and one or more camera assemblies 44. According to another embodiment, the motor unit 40 can form part of a robotic support system. The implantable robotic arm 42 and the camera assembly 44 can form part of a single support axis robotic unit or subsystem as disclosed and described in U.S. Patent Application No. PCT / US20 / 39203, or can form part of a split-arm (SA) architecture robotic system as disclosed and described in PCT Patent Application No. PCT / US20 / 39203.

[0039] The control signals generated by the control unit 26 may be received by a motor unit 40 of the robot subsystem 20. The motor unit 40 may include a series of servo motors and gears configured to separately drive a robot arm 42 and a camera assembly 44 of the robot subsystem 50. The robot arm 42 may be controlled to follow the reduced movement or motion of the surgeon's arm sensed by associated sensors. The robot arm 42 may have parts or regions associated with shoulder, elbow, and wrist joints as well as movements that may be associated with a user's fingers. For example, a robot elbow joint may follow the position and orientation of a human elbow and a robot wrist joint may follow the position and orientation of a human wrist. The robot arm 42 may also be associated with a terminal region that may terminate in an end effector or gripping device that follows the movement of one or more fingers of a user, such as, for example, an index finger when the user pinches the index finger and thumb together. The robot shoulder is fixed in position while the robot arm follows the movement of the user's arm. In one embodiment, the position and orientation of the user's torso is subtracted from the position and orientation of the user's arm. This subtraction allows the user to move the torso without the robot arm moving.

[0040] The robotic camera assembly 44 is configured to provide the surgeon with image data 48, such as, for example, a live video feed of the operation or surgical site, as well as to allow the surgeon to operate and control the cameras forming part of the camera assembly 44. The camera assembly 44 preferably includes a pair of cameras whose optical axes are axially separated by a selected distance, known as the inter-camera distance, to provide a stereoscopic view or image of the surgical site. The surgeon can control the movement of the cameras through the movement of a head mounted display, or through sensors coupled to the surgeon's head, or using a hand controller or sensors that track the movement of the user's head or arm, thereby allowing the surgeon to intuitively and naturally obtain a desired view of the surgical site. The cameras are movable in multiple directions, including, for example, yaw, pitch, and roll, as is known. The components of the stereoscopic camera can be configured to provide a natural and comfortable user experience. In some embodiments, the inter-camera distance between the axes can be modified to adjust the depth of the surgical site perceived by the user.

[0041] According to one embodiment, the camera assembly 44 may be actuated by the movement of the surgeon's head. For example, during surgery, if the surgeon wishes to view an object located above the current field of view (FOV), the surgeon looks upward, which causes the stereoscopic camera to be rotated upward about the pitch axis from the user's perspective. The image or video data 48 generated by the camera assembly 44 may be displayed on the display unit 12. If the display unit 12 is a head-mounted display, the display may include an embedded tracking and sensor system 16A that obtains raw orientation data in the yaw, pitch and roll directions of the HMD, as well as position data in Cartesian space (x,y,z) of the HMD. However, alternative tracking systems may be used to provide supplemental position and orientation tracking data for the display instead of or in addition to the HMD's embedded tracking system.

[0042] Image data 48 generated by the camera assembly 44 may be communicated to the virtual reality (VR) computing unit 14 and processed by the VR or image rendering unit 30. The image data 48 may include still photographic or image data as well as video data. The VR rendering unit 30 may include suitable hardware and software for processing the image data and then rendering the image data for display by the display unit 12, as known in the art. Additionally, the VR rendering unit 30 may combine the image data received from the camera assembly 44 with information associated with the position and orientation of the cameras in the camera assembly and with information associated with the position and orientation of the surgeon's head. With this information, the VR rendering unit 30 may generate an output video or image rendering signal and transmit this signal to the display unit 12. That is, the VR rendering unit 30 renders a reading of the position and orientation of the hand controllers and the surgeon's head position for display on the display unit, such as, for example, on an HMD worn by the surgeon.

[0043] The VR computing unit 14 may also include a virtual reality (VR) camera unit 38 for generating one or more virtual reality (VR) cameras for use or placement in the VR world displayed in the display unit 12. The VR camera unit 38 may generate one or more virtual cameras in the virtual world, which may be used by the system 10 to render images for the head mounted display. This ensures that the VR camera always renders the same view that a user wearing the head mounted display would see in the cubemap. In one embodiment, a single VR camera may be used, while in another embodiment, separate left and right eye VR cameras may be used to render onto separate left and right eye cubemaps in the display to provide a stereo view. The FOV settings of the VR camera may self-configure relative to the FOV exposed by the camera assembly 44. In addition to providing a contextual background for the live camera view or image data, the cubemap may be used to generate dynamic reflections on virtual objects. This effect allows reflective surfaces on the virtual objects to pick up reflections from the cubemap, making it appear as if these objects are actually reflecting their real world environment.

[0044] The robot unit 50 may employ multiple different robot arms 42 that may be deployed along different or separate axes. Additionally, the camera assembly 44 that may employ multiple different camera elements may also be deployed along a common separate axis. Thus, the robot unit 50 employs multiple different components, such as a pair of separate robot arms and camera assemblies 44 that may be deployed along different axes. Additionally, the robot arms 42 and camera assemblies 44 are separately operable, steerable, and movable. The robot subsystem 20, including the robot arms and camera assemblies, may be disposed along separate operable axes to form an SA architecture. The SA architecture is designed to simplify and increase the efficiency of the insertion of a robotic surgical instrument through a single trocar at a single insertion point or site, while also aiding in the deployment of the surgical instrument into a surgical-ready state, as well as the subsequent removal of the surgical instrument through the trocar. As an example, a surgical instrument may be inserted through a trocar to access a patient's body cavity and perform an in vivo procedure. In some embodiments, a variety of surgical instruments may be utilized, including, but not limited to, robotic surgical instruments and other surgical instruments known in the art.

[0045] In some embodiments, the robotic subsystem 20 of the present invention is supported by the RSS with multiple degrees of freedom so that the robotic arm 42 and camera assembly 44 can be maneuvered within the patient to a single location or multiple different locations. In one embodiment, the robotic subsystem 20 can be directly attached to the RSS. In other embodiments, the RSS of the surgical robotic system 10 can optionally include a motor unit 40 coupled at one end to the robot unit 50 and coupled at an opposite end to an adjustable support member or element. Alternatively, as shown herein, the motor unit 40 can form a part of the robotic subsystem 20. The motor unit 40 can include gears, one or more motors, drive trains, electronics, etc. for powering and driving one or more components of the robotic arm and camera assembly (e.g., the robotic unit 50). The robotic unit 50 can be selectively coupled to the motor unit 40. According to one embodiment, the RSS can include a support member having the motor unit 40 coupled to its distal end. The motor unit 40 can be coupled to each of the camera assembly 44 and the robotic arm 42. The support members may be configured and controlled to cause one or more components of the robotic unit 50 to move in a linear manner, or in any other selected direction or orientation.

[0046] The motor unit 40 can also provide mechanical power, power, mechanical communication, and electrical communication to the robotic unit 50 and can further include an optional controller for processing input data from one or more of the system components (e.g., the display 12, the sensing and tracking unit 16, the robotic arm 42, the camera assembly 44, etc.) and generating control signals in response thereto. The motor unit 40 can also include a memory element for storing data. Alternatively, the motor unit 40 can be controlled by the computing unit 18. Thus, the motor unit 40 can generate signals for controlling one or more motors that can control and drive the robotic arm 42, including, for example, the position and orientation of each articulating joint of each arm, as well as the camera assembly 44. The motor unit 40 can further provide translational or linear degrees of freedom that are primarily utilized to insert and remove each component of the robotic unit 50 through a suitable medical device, such as a trocar 108. The motor unit 40 can also be used to adjust the insertion depth of each robotic arm 42 as it is inserted into the patient 100 through the trocar 108.

[0047] The present invention is directed to the ability to easily and efficiently replace tools that form the end effectors of the robotic arms of the present invention. The ability to easily replace tools allows a user, such as a surgeon, to only remove and replace the end effector portion of the robotic arm, rather than replacing the entire robotic arm, which typically has a dedicated tool attached to it. Removal and replacement of tool elements can be done inside or outside the patient. By not having to replace the entire robotic arm, the robotic arm of the present invention reduces costs and waste as the user does not have to use the entire suite of robotic arms and associated tools.

[0048] 2A and 2B show a general design of selected components of a robotic arm 42 of a surgical robotic unit 50 according to the teachings of the present invention. The illustrated robotic arm may be cable driven by a suitable cable and employs an end effector 52 at an end effector region or portion of the arm 42. The end effector provides a highly functional and easy to use mechanical connection that allows for grasping and manipulation of devices or tissue. For simplicity, only a single robotic arm 42 is shown, but a second or subsequent robotic arm may be similar or identical in form and function. The illustrated robotic arm 42 may include a series of articulating segments 56 that form joint sections corresponding to the joints of a human arm. For example, articulating section 54A of the robotic arm 42 forms a wrist joint, articulating section 54B forms an elbow joint, and articulating section 54C forms a shoulder joint. In this manner, the articulating segments 56 may be constructed and combined to provide rotational and / or hinged movement to mimic the joints of a human arm. The articulating segments 56 of the robotic arm 42 are constructed to provide, for example, cable-driven rotational movement, but within reasonable rotational limits. The articulating segments 56 are configured to provide maximum torque and speed with minimum size. The articulating segments 56 are mechanically coupled together and terminate at an end effector portion or segment 52. FIG. 2B shows that the end effector portion 52 and adjacent arm segment 56 form a wrist joint 54A of the robotic arm 42.

[0049] 3A-9, one or more of the articulating segments 56 of the robotic arm 42 may be constructed from multiple mechanical components forming a rotational actuation mechanism that can rotate relative to one another to achieve rotational movement of the segment or joint. The articulating segments 56 may be constructed such that the computing unit 18 can easily and simply determine the rotational position of a portion of the articulating segment. The articulating segments 56 include a body 60 that includes two main functional component groups, namely a male segment assembly 62 and a female segment assembly 82 for forming the rotational actuation mechanism. The male segment assembly 62 and the female segment assembly 82 are housed within a main housing 120. The male segment assembly 62 has a degree of freedom to rotate relative to the female assembly 72, similar to the function of a bearing. The male segment assembly is rotated by a suitable cable coupled thereto, as known in the art. The illustrated male segment assembly 62 may include a rotating shaft element 64 having a body with an outer surface 66. The rotating shaft element 64 also has a flange element 68 formed at one end and has an inner chamber 70. The inner chamber 70 allows wires and cables to pass through the articulation segment. The male segment assembly 62 also includes an engagement element 72 that seats on and contacts the outer surface 66 of the rotating shaft element 64 through known mechanical interference and fastening techniques, such as brazing, welding, adhesives, etc., such that the engagement element 72 is rotatably coupled to the shaft element 64. The engagement element 72 has an outer surface that includes a groove 74 formed therein at one end and an opposing skirt element 76 formed at an opposing end. The groove 74 can be any selected type of groove, and is preferably a helical or helical shaped groove. In this regard, the groove 74 can be formed in a spiral shape around a portion of the outer surface of the engagement element 72, the groove 74 being configured to form stop elements 74A, 74B at one end of the groove in FIG. 4. The articulation segment 56 further includes a rear bearing element 110 mounted about the outer surface 66 of the rotating shaft element 64. The bearing element 82 is disposed adjacent to and preferably contacts the flange 68 of the rotating shaft element 64.The articulation segment 56 also includes a front bearing element 112 disposed about the outer surface 66 of the rotating shaft member at an end opposite the flange 68. The flange element 112 is disposed adjacent an axial end portion of the engagement element 72. The bearing elements 110, 112 help the male segment assembly 62 to rotate easily when mounted within the female segment assembly 82 and main housing 120. The male segment assembly may be rotated by one or more cables.

[0050] The illustrated female segment assembly 82 is sized and dimensioned to accommodate the male segment assembly 62. The female segment assembly 82 can include an outer housing element 84 that seats around an outer surface of the engagement element 72. The outer housing element 84 can include a tail portion 88 disposed at an end portion that covers the skirt element 76 of the engagement element 72. The outer housing element 84 forms an outer portion of the female segment assembly 82 and can include a space or slot 86 formed in the outer surface for seating a shuttle assembly 98. The shuttle assembly 98 is configured to move linearly or axially within the slot 86 as the male segment assembly 62 rotates. The shuttle assembly can be any component or series of components configured to communicate with or contact a portion of a groove to travel along it. According to one embodiment, the shuttle assembly 98 includes a shuttle element 100 having a magnet 102 coupled thereto at one end. The shuttle element 100 also includes groove contacting elements, such as bearings 104, sized and configured to seat within the groove 74 and within the shuttle element 100 at opposing ends. According to an alternative embodiment, the shuttle assembly 98 simply includes a shuttle element, without the need for bearings or magnets, to contact the groove 74 and move or ride along the groove as the male segment assembly 62 rotates. The shuttle element can have any selected shape, size, or configuration suitable for direct or indirect communication with the groove 74 and / or slot 86. Rotational movement of the male segment assembly 62 translates into linear or longitudinal movement of the shuttle assembly 98 as the bearings 104 track or move along the groove 74 as the male segment assembly 62 rotates. Stop elements 74A, 74B formed along the endpoints of the groove 74 function as groove end indicators to define the range of movement of the bearing within the groove 74 and therefore the range of axial movement of the shuttle assembly 98 within the slot 86. The stop elements also function as endpoints that define the maximum number of rotations of the male segment assembly.The female segment assembly 82 also includes an abutment element 90 axially disposed between the bearing element 110 and an outermost end surface of the skirt element 76 of the engagement element 72. The abutment element 90 functions as a mechanical separator to separate the bearing element 110 from the rotatable engagement element 72. The outer housing element 84, which may be coupled to one or more proximal components of the robotic arm 42, and the rotating shaft element 64 of the male assembly 62, may be attached to one or more distal components of the robotic arm 42.

[0051] 3A-3B and 10-12, the articulating segment 56 may further include other structures such as, for example, a sensing magnet 114 coupled to the rotating shaft element 64 of the male assembly 62 and rotating therewith. The sensing magnet 114 is used by the system to sense and determine the incremental rotation angle of the male segment assembly 62. Specifically, the male segment assembly 62 may rotate a selected number of turns, each turn corresponding to a full and complete 360 ​​degrees. The articulating segment 56 may also include a printed circuit board (PCB) 160 coupled to the outer housing element 84 of the female assembly 82 for mounting and positioning a series of sensor elements including sensors and magnets to measure relative rotational movement or motion within the joint formed by the articulating segment 56. For example, the PCB 160 may employ a series of position sensors 162 to generate sensor data indicative of the relative rotational position of the sensing magnet 114 rotating with the rotating shaft element 64. The sensors 162 may be any selected type of sensor and may include Hall effect sensors. When the PCB 160 is attached to the female segment assembly 82, the sensor 162 is generally circumferentially aligned with the annular sensing magnet 114 so as to sense the rotational position of the magnet 114. As a simple example, the sensing magnet 114 rotates with the rotating shaft element 64, and the sensor 162 positioned around the magnet 114 senses the rotational or angular position of the magnet. The sensor 162 generates sensor data in response to the position of the magnet 114 received by the computing unit 18, which determines the particular rotational angle or position of the magnet, and therefore that of the male segment assembly 62 (e.g., partial rotation position). Thus, when the male segment assembly 62 and associated sensing magnet 114 make a quarter turn, the sensor 162 senses the inward or partial rotation angular position of the magnet 114, and the computing unit 18 correlates the sensed electromagnetic strength of the sensing magnet 114 to a particular rotation angle, 90 degrees in the current example.

[0052] The PCB 160 may also include an additional sensor 164, such as a Hall effect sensor, mounted on a section 170 of the PCB 160. The PCB section 170 may be mounted adjacent to the slot 86, with the sensors 164A and 164B mounted thereon positioned at opposite ends of the slot 86, i.e., opposite ends of the groove 74. The shuttle element 100 and associated magnet 102 interact with the sensors 164A, 164B to measure the relative position of the magnet 102 between the sensors 164A, 164B. The magnet 102 moves along a linear path within the slot 86 between the additional sensors 164A, 164B and is driven by the relative motion between the male assembly 62 and the female assembly 82. The linear travel of the shuttle assembly 98 is proportional to the full multi-turn range of motion (e.g., + / - 2 turns from a neutral position) of the rotating shaft member 64 and associated engagement element 72. In addition, one skilled in the art will readily recognize that the linear travel of the shuttle assembly can correspond to any selected number of full rotations of the male segment assembly, and preferably exceeds one full rotation. The slot 86 allows the shuttle assembly 98 to move back and forth within the linear slot 86 as the bearings 104 travel within and along the grooves 74 as the engagement members rotate. Thus, relative motion of the surfaces of the male segment assembly 62 and the female segment assembly 82 rotates the grooves 74 in a selected direction, linearly moving the shuttle assembly 98 within the slot, similar to a ball screw mechanism. The sensors 164A, 164B sense the relative position of the magnets 102 of the shuttle assembly 98 within the slot 86 as the shuttle assembly approaches either of the hard stops 74A, 74B, and this information is processed by the computing unit 18 to determine the absolute rotational position of the rotating shaft element 64 of the male assembly 62 as well as the number of turns of a full rotation. Specifically, the position of the shuttle assembly 98 within the slot 86 may be correlated to the position of the bearing 104 within the groove 74 , which may be correlated to the rotational position or number of rotations of the male segment assembly 62 .According to another embodiment, only the linear position of the shuttle element 100 can be used to calculate the rotational position of the rotating shaft member 64 within its full range of motion (>360 degrees). According to yet another embodiment, the accuracy of the measurement or determination of the rotational position can be improved by including the rotational position data received from the sensing magnet 114 and its associated sensor 162. In this embodiment, the calculated rotational position, and the associated signal from the sensor 162, is periodic within one full rotation of the joint and therefore cannot sense the rotational position of the male assembly beyond one full turn. Thus, rotating the rotating shaft element 64, and therefore the joint, beyond one full rotation can cause the signal to "wrap" or reset, making the absolute rotational position unknown. This is overcome by incorporating sensor data generated by the slot sensors 164A, 164B, which can be utilized by the computing unit 18 to determine the number of full rotations of the male segment assembly or its components. The computing unit 18 can process the sensor data from the sensor 164 indicating the number of full rotations of the male segment assembly 62, as well as the sensor data from the sensor 162 indicating the partial rotations of the male segment assembly, and generate an absolute rotational position of the male segment assembly based thereon. The sensor data can be correlated with the number of rotational turns by comparing the measured signal strength from each sensor to pre-stored measurements, or by using simple algorithms and device geometry. The articulating segment 56 can employ incremental sensing assemblies including sensing magnets 114 and associated sensors 162, which in combination can provide relatively high resolution joint rotation angle information to the computing unit 18 within a single rotation, but typically do not determine the exact number of rotational turns and turn count of the associated joint. In this way, the incremental sensors (e.g., sensors 114 and 162) can assist in determining the relative rotational angles of the joints of a robotic arm, but cannot assist in determining the specific number of rotations of the robotic arm.Combining this information with the sensory data provided by the additional sensor 164 allows the system to determine the specific number of rotations of the male segment assembly 62, and therefore the joint. Those skilled in the art will readily recognize that the sensor data generated by the sensor 164 can also be used to determine the rotation angle of the male segment assembly, and thus the sensor 162 and sensing magnet 114 can be any component of the surgical robotic arm.

[0053] 4-10 and 13A-13B illustrate the relative movement of the bearing 104 in the helical or spiral groove 74. Specifically, as the male segment assembly 62 rotates relative to the female segment assembly 82, the bearing 104 moves along the helical groove 74 in a direction relative to or opposite to the direction of rotation of the male segment assembly. The bearing 104 is coupled to the shuttle element 100, such that the rotational movement of the rotating shaft element 64 and associated engagement member 66, along with the movement of the bearing 104 within the helical groove 74, converts or translates the rotational movement of the male segment assembly (e.g., the rotating shaft element 64 and associated engagement element 72) into linear movement of the shuttle assembly 98. In this manner, the shuttle assembly 98 moves linearly or axially back and forth within the slot 86 along a linear path 106. The male segment assembly 62 can rotate a sufficient number of turns such that the bearing 104 reaches a hard stop 74B formed within the groove 74, as shown in FIGS. 5A and 5B. In this position, the shuttle element 100 and associated magnet 102 are positioned immediately adjacent to the sensor 164B and sensing magnet 114. In this position, the sensor 164B senses the strongest magnetic force and associated polarity from the magnet 102, and the sensor 164B generates sensor data indicative of the position of the magnet and therefore the position of the shuttle assembly. The sensor data can be processed such that the system 10 can determine from the sensor data that the joint has been rotated to a maximum rotation position and amount of turns in a selected direction. The male segment assembly 62 may then be rotated in the opposite direction to move the ball bearing 104 away from the hard stop 74B and correspondingly move the shuttle element 100 and magnet 102 away from the sensor 164B and toward the opposing sensor 164A. The system can store preselected information such that the system can determine that the maximum sensor signal from either of the sensors 164A and 164B indicates or corresponds to a rotation position corresponding to approximately two full turns from a neutral or center position (e.g., ±2 full turns).A signal from sensor 164B having a bearing 104 located at stop 74B indicates that the articulation segment 56 has been rotated to a maximum extent. According to one embodiment, the male segment assembly rotates two full turns from a center or neutral position. The sensor data generated by sensors 164A, 164B cannot be utilized by the computing unit 18 to determine the rotational angle of the male segment assembly 62. In this manner, the system 10 can use the sensor 162 and the sensing magnet 114 to determine the rotational position of the male segment assembly 62 within a single turn (e.g., a partial angle of rotation).

[0054] FIG. 6 shows the position of the shuttle assembly 98 after one full rotation of the male assembly 62 in the opposite direction. In this position, the bearing 104 is positioned in the second row of the helical groove 74. The shuttle assembly 98 can move from this position in either direction along the slot 86 depending on the direction of rotation of the male segment assembly 62. FIG. 7 illustrates the position of the bearing 104 in the third row of the helical groove 74 after two full rotations of the male segment assembly 62. The illustrated position corresponds to or may be considered as a net neutral or mid-rotation position since it is located at the midpoint between stops 74A and 74B. Thus, the shuttle assembly 98 is moved linearly along the linear path 106 further away from the sensor 164B and closer to the sensor 164A. FIGS. 8, 13A and 13B show the position of the bearing 104 after three full rotations of the male segment assembly 62. After four full rotations of the male segment assembly 62, the bearing 104 reaches or contacts the opposing hard stop 74A, as shown in FIG. 9. In this position, the shuttle element 100 and magnet 102 are positioned immediately adjacent to the sensor 164A. The sensor data generated by the sensors 164A, 164B, indicating the relative linear position of the magnet 102, can be correlated by the computing unit 18 with a particular number of turns or revolutions of the male segment assembly 62. For example, when the sensor 164A generates a signal having a maximum strength or magnitude, the system 10 can determine from the magnitude of the signal that the articulation segment 56 has been rotated to a maximum extent in that particular direction. The signal strength or magnitude from the sensors 164A, 164B can be correlated with the position of the ball bearing 104 and therefore the number of revolutions or turns of the male segment assembly 62.

[0055] According to another embodiment of the present invention, the number of turns or revolutions of the male segment assembly 62 as calculated by the computing unit 18 can be used to directly determine the total absolute rotation angle of the male assembly, where the absolute rotation angle may point to one of two hard stop positions and is equal to about 900 degrees from the respective hard stop positions. Still further, the sensor 162 and the incremental or sensing magnet 114 can be used to determine the incremental rotation angle position of the male segment assembly 62 within a single rotation turn with greater accuracy. Thus, the magnet 102 and the slot sensor 164A, 164B can determine the absolute number of turns or revolutions of the male segment assembly 62, and the incremental sensing magnet 114 and associated sensor 162 can determine the specific incremental rotation angle or position of the assembly 62 within a single rotation turn. In other similar embodiments, the data from the sensor 162 and the incremental magnet element 114, as well as the data from the magnet 102 and the sensors 164A and 164B can be combined by utilizing a filtering algorithm, such as a Kalman filter or other known filtering algorithms, as known in the art. The combination of two sensor data sources has the advantage of significantly increasing the accuracy of the estimate or determination of the rotational angular position of the revolute joint. Overall, this highly accurate rotational position determination methodology of the present invention allows the system 10 to determine the position of the revolute joint at any point, particularly at start-up.

[0056] 14A and 14B illustrate another embodiment of an articulating segment 56 in accordance with the teachings of the present invention. As shown, the articulating segment 56 may use only a single sensor 164C associated with the slot 86. Data generated by the sensor 164C and indicative of the relative linear position or location of the magnet 102 may be correlated by the computing unit 18 with a particular number of turns or revolutions of the male segment assembly 62. A potential disadvantage of using only the single sensor 164C compared to using the opposed dual sensors 164A and 164B is a reduction in overall accuracy. However, the information generated by the single sensor 164C is suitable for use.

[0057] FIG. 15 illustrates another embodiment of the multi-turn rotation actuation mechanism of the present invention. The illustrated rotation actuation mechanism 130 may be used by the articulation segment 56 of the present invention to implement multi-turn rotation of one or more components of the male segment assembly 62, for example, while using or incorporating hard stops in grooves formed therein. The illustrated actuation mechanism 130 includes a housing 132 including a plurality of bearings 134 housed therein. The housing 132 includes an engagement mechanism 136 for engaging with, for example, the rotating shaft member 64 or the engagement element 72 of the male segment assembly 62. The illustrated rotation actuation mechanism 130 may incorporate any selected number of rotations by adding stages, for example, as shown in FIG. 16, and preferably allows the components to rotate over a range of 540 degrees. The bearings 134 of the actuation mechanism 130 allow the male segment assembly to rotate relative to the main body 132. The engagement mechanism 136 may include an inner contour 138A and an outer contour 138B having different radii. Hard stop B indicates the maximum extent or degree that the rotary actuation mechanism can rotate.

[0058] A simplified embodiment of a hard stop design for the rotary actuation mechanism 130 is illustrated in FIG. 17. FIG. 17 shows an inner contour 138A and an outer contour 138B in which a single ball bearing 150 is positioned and allowed to move freely in or along a circular groove 152 forming a circular path 154. The inner contour 138A includes an inner protrusion 156A and the outer contour 138B includes an outer protrusion 156B. The opposing surfaces of the outer protrusion 156B form first and second hard stop elements including hard stop B, where the inner protrusion 156A engages the bearing 150 when rotated, forcing it to move along the circular path 154. In combination, the inner contour 138A, the outer contour 138B constitute one stage of the rotary actuation mechanism 130. The theoretical maximum range of 720 degrees for the current mechanism is typically not achieved due to mechanical constraints and the overlap required to accommodate the ball bearing 150. Hard stop limits above 720 degrees can be achieved by adding additional stages, which can be arranged radially inward or axially in series, as needed. In the illustrated embodiment, there is a 40 degree section of the outer contour 138B formed by the outer protrusion 156B offset radially inward, and there is a 40 degree section of the inner contour 138A formed by the inner protrusion 156A offset radially outward. The angle of the offset section can be chosen at will. Thus, about 40 degrees is chosen, suitable for the total range of circular or rotary motion. The inner contour 138A rotates about the bearing axis (i.e., the axis perpendicular to the ring of bearing balls) relative to the outer contour 138B. As inner contour 138A rotates approximately 320 degrees counterclockwise (step 3), inner protrusion 156A contacts or engages bearing 150 and begins to move the bearing along circular path 154 in a counterclockwise direction until the inner and outer 40 degree sections formed by protrusions 156A, 156B are aligned. As inner contour 138A continues to rotate counterclockwise, protrusion 156A continues to push ball bearing 150 counterclockwise within groove 152 along circular path 154.As inner contour 138A and bearing 150 rotate another 305 degrees, bearing 150 contacts outer protrusion 156B at a second or other hard stop at point B, as shown in step 5. Thus, the total range of motion between the two hard stops formed by outer protrusion 156B can be calculated as follows: 2N-N*(θi+θo+2θb) Equation 1 where N equals the number of steps, θi equals the angle of the inner section, θo equals the angle of the outer section, and θb equals the angle that the bearing 150 takes up in the profile.

[0059] FIG. 16 is yet another embodiment of the multi-turn rotary actuation mechanism of the present invention. The present invention includes a rotary assembly 140 that may be incorporated into the articulating segment 56, including a rotary element 142 having a series of concentric rotary grooves or steps 144 formed therein. The grooves 144 of the rotary element 142 may include one or more hard stop elements 146A, 146B. The grooves 144 mirror in some respects the inner contours 138A, 138B, respectively, of the actuation mechanism 130. To extend the range of motion to four full rotations, the inner contours 138A, 138B are repeated by the concentric nature of the grooves 144. This creates hard stops at either end of the rotation range. Additional steps may be added to extend the range of hard stops.

[0060] It is therefore believed that the present invention efficiently attains the objects set forth above in what has become apparent from the foregoing description. It is intended that all matter contained in the above description or shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense, since certain changes may be made in the above construction without departing from the scope of the invention.

[0061] It is also to be understood that the following claims are intended to cover all the general and specific features of the invention described herein, as well as all statements of the scope of the invention that are said to apply as a matter of language.

[0062] Having thus described the invention, what is new and desired to be claimed and secured by Letters Patent is as follows:

Claims

1. A surgical robot arm of a surgical robot system comprising a plurality of articulated motion segments mechanically and operatively coupled together, wherein one or more of the plurality of articulated motion segments:

1. A male segment assembly comprising: a rotating shaft element having a body with an outer surface; an engaging element coupled to the outer surface of the rotatable shaft member and having a helical groove formed thereon; and a female segment assembly having an outer housing element disposed about at least a portion of the engaging element and having a slot formed therein exposing at least a portion of the groove; a shuttle assembly mounted in the slot formed in the outer housing element, a portion of the shuttle assembly seated in the groove of the engagement element; A surgical robotic arm, wherein the male segment assembly is disposed within the female segment assembly and is rotatable relative to the female segment assembly about a longitudinal axis and is rotatable greater than about 360 degrees.

2. A surgical robot arm as described in claim 1, further comprising a bearing element disposed around a portion of the outer surface of the rotating shaft element.

3. A surgical robot arm as described in claim 2, wherein the rotating shaft element has a flange element formed at one end, the engaging element has a skirt element formed at one end, and the female segment assembly further comprises an abutment element axially positioned between the skirt element of the engaging element and the bearing element to axially separate the engaging element from the bearing element.

4. A surgical robot arm as described in claim 1, further comprising a first sensor assembly configured to sense the position of the shuttle assembly within the slot and generate first sensor data.

5. A surgical robot arm as described in claim 4, wherein the first sensor data is processed to determine one or more of a number of turns of the male segment assembly and a rotational angular position of the male segment assembly.

6. A surgical robot arm as described in claim 4, further comprising a second sensor assembly configured to sense a rotational angular position of the male segment assembly and generate second sensor data.

7. The surgical robot arm of claim 6, further comprising a computing unit for processing the first sensor data and the second sensor data to determine a rotational position of the joint.

8. The surgical robot arm of claim 1, further comprising a sensor assembly coupled to one or more of the male segment assembly and the female segment assembly for sensing the rotational position of the male segment assembly.

9. The sensing assembly, a first plurality of sensors for generating first sensor data indicative of a number of rotations of the male segment assembly; 9. The surgical robot arm of claim 8, comprising: a second plurality of sensors for generating second sensor data indicative of a rotational angular position of the male segment assembly, the first sensor data and the second sensor data being processable to determine the rotational position of the male segment assembly.

10. A surgical robot arm as described in claim 9, wherein the groove has a first hard stop formed at one end and a second hard stop formed at an opposing end, the shuttle assembly is movable within the groove to an extent greater than 360 degrees upon rotation of the male segment assembly, and the first hard stop and second hard stop determine a maximum number of rotations of the one or more structural components of the male segment assembly.

11. The surgical robot arm of claim 1, wherein the shuttle assembly comprises: a bearing element sized and configured to communicate with the groove; a shuttle element having a first end with a recess formed therein for seating a first portion of the bearing element; and a shuttle magnet coupled to a second opposing end of the shuttle element.

12. The surgical robot arm of claim 11, further comprising a first plurality of sensors associated with the slots formed in the outer housing element for sensing a linear position of the shuttle magnet within the slots and generating first sensor data.

13. The surgical robot arm of claim 12, wherein the first plurality of sensors comprises a first slot sensor associated with one end of the slot and a second slot sensor associated with an opposing end of the slot.

14. The surgical robot arm of claim 13, wherein the first sensor data indicates a rotation speed of the male segment assembly.

15. The surgical robot arm of claim 14, wherein the first sensor data is processed to determine a rotational angular position of the male segment assembly.

16. The surgical robot arm of claim 14, further comprising an annular sensing magnet rotatably coupled to the rotating shaft element or the engaging element of the male segment assembly.

17. The surgical robot arm of claim 16, further comprising a second plurality of sensors arranged circumferentially around the annular sensing magnet for sensing a rotational angular position of the annular sensing magnet and generating second sensor data indicative of a rotational angular position of the male segment assembly.

18. A surgical robot arm as described in claim 14, wherein the groove has a first stop element formed at a first end of the groove and a second stop element formed at an opposing second end of the groove, the first and second stop elements defining a maximum number of rotations of the male segment assembly.

19. 1. A surgical robot arm of a surgical robot system, comprising a plurality of articulating segments mechanically and operably coupled together to form one or more joints, wherein one or more of the plurality of articulating segments comprises: a male segment assembly, the male segment assembly being rotatable about its longitudinal axis by one or more cables and having one or more structural components that are rotatable to greater than 360 degrees; a rotational actuation mechanism having a male segment assembly seated therein and a female segment assembly sized and configured to be operably coupled with the male segment assembly.

20. 20. The surgical robotic arm of claim 19, wherein the female segment assembly includes a linear slot, and the one or more structural components include a groove, further comprising a shuttle assembly having a shuttle element sized and configured to contact the groove such that the shuttle element moves linearly within the slot as the male segment component rotates.

21. The surgical robot arm of claim 20 , further comprising a first sensor assembly configured to sense a linear position of the shuttle element within the slot and generate first sensor data.

22. 22. The surgical robot arm of claim 21, wherein the first sensor data is processed to determine one or more of a number of turns of the one or more structural components of the male segment assembly and a rotational angular position of the one or more structural components.

23. 22. The surgical robot arm of claim 21, further comprising a second sensor assembly configured to sense a rotational angle of the one or more structural components of the male segment assembly and generate second sensor data.

24. The surgical robotic arm of claim 23, further comprising a computing unit for processing the first sensor data and the second sensor data to determine a rotational position of the joint.

25. 20. The surgical robot arm of claim 19, further comprising a sensor assembly coupled to one or more of the male segment assembly and the female segment assembly for sensing a rotational position of the one or more structural components of the male segment assembly.

26. the sensing assembly comprising: a first plurality of sensors for generating first sensor data indicative of a number of rotations of the one or more structural components of the male segment assembly; 26. The surgical robot arm of claim 25, comprising: a second plurality of sensors for generating second sensor data indicative of a rotational angular position of the one or more structural components of the male segment assembly, wherein the first sensor data and the second sensor data can be processed to determine the rotational position of the one or more structural components of the male segment assembly.

27. 27. The surgical robot arm of claim 26, wherein the one or more structural components of the male segment assembly include a groove formed therein for seating a shuttle element configured to move along a path, the groove having a first hard stop formed at one end of the path and a second hard stop formed at an opposing end of the path, the shuttle element is movable within the groove to an extent greater than 360 degrees upon rotation of the male segment assembly, and the first hard stop and the second hard stop determine a maximum number of rotations of the one or more structural components of the male segment assembly.

28. The surgical robot arm of claim 27 , wherein the shuttle element is a bearing.

29. The surgical robot arm of claim 27, wherein the groove is a circular groove or a spiral groove.

30. 28. The surgical robot arm of claim 27, wherein the groove is a spiral groove and the female segment assembly includes a slot formed therein, the slot configured and positioned to communicate with at least a portion of the groove.

31. 31. The surgical robot arm of claim 30, further comprising the shuttle element, a first magnet coupled to one end of the shuttle element, and a bearing coupled to an opposing end of the shuttle element for contacting the groove, wherein the shuttle assembly is configured to move linearly within the slot.

32. The surgical robot arm of claim 31 , wherein the first plurality of sensors are configured to sense a position of the first magnet within the slot and generate the first sensor data.

33. 33. The surgical robot arm of claim 32, further comprising a second magnet coupled to and rotatable with the one or more structural components of the male segment assembly, the second plurality of sensors configured to sense a rotational angular position of the second magnet and generate the second sensor data.

34. The surgical robot system includes a computing unit, the computing unit comprising: configured to receive the first sensor data and determine the number of rotations of the one or more structural components of the male segment assembly based on the first sensor data; 27. The surgical robot of claim 26, configured to receive the second sensor data and determine the rotational angular position of the one or more structural components of the male segment assembly based on the second sensor data.

35. The one or more structural components of the male segment assembly include: a rotating shaft element having a body with an outer surface; 33. The surgical robot of claim 32, comprising: an engagement member coupled to the outer surface of the rotating shaft member, the engagement member having the outer surface with the groove formed therein.

36. 36. The surgical robot arm of claim 35, wherein the female segment assembly comprises an outer housing element disposed about at least a portion of the engaging element and having a slot formed therein exposing at least a portion of the groove.

37. 37. The surgical robot arm of claim 36, wherein the female segment assembly further comprises an abutment element for axially separating the engagement element from a bearing element disposed about a portion of the outer surface of the rotating shaft element.

38. 1. A method for rotating a joint portion of a surgical robot arm of a surgical robot system, comprising: providing the robotic arm having one or more articulating segments mechanically and operably coupled together to form the joint, the articulating segment including a male segment assembly having one or more rotatable structural components, and a female segment assembly sized and configured to seat the male segment assembly; rotating the structural component of the male segment assembly about its longitudinal axis with one or more cables, the structural component being rotatable to a degree greater than about 360 degrees; and sensing a rotational position of the structural component of the male segment assembly with a sensor assembly coupled to one or more of the male segment assembly and the female segment assembly.

39. generating first sensor data at the sensor assembly; 40. The method of claim 38, further comprising: determining a number of rotations of the structural component of the male segment assembly from the first sensor data.

40. 40. The method of claim 39, further comprising determining a rotational angular position of the structural component of the male segment assembly from the first sensor data.

41. generating first sensor data at the sensor assembly; determining a number of rotations of the structural component of the male segment assembly from the first sensor data; generating second sensor data with the sensor assembly; determining a rotational angular position of the structural component of the male segment assembly from the second sensor data; 40. The method of claim 38, wherein the first sensor data and the second sensor data can be processed to determine the rotational position.

42. providing a groove in the structural component of the male segment assembly for seating a shuttle element configured to travel along a path, the groove having a first hard stop formed at one end of the path and a second hard stop formed at an opposing end of the path; and moving the shuttle element within the groove greater than 360 degrees upon rotation of the structural component; 42. The method of claim 41, wherein the first hard stop and the second hard stop determine a maximum number of rotations of the one or more structural components of the male segment assembly.

43. associating a first magnet with the shuttle element; 43. The method of claim 42, further comprising sensing a position of the first magnet within the groove with the sensor assembly.

44. coupling a second magnet to the structural member of the male segment assembly; 44. The method of claim 43, further comprising sensing a rotational angular position of the second magnet with the sensor assembly.

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