Repositioning a supporting structure of a computer-assisted system

Abstract

A computer-assisted system includes a repositionable assembly configured to support and move one or more instruments. The computer-assisted system further includes a control system including one or more processors and communicatively coupled to the repositionable assembly. The control system is configured to determine a virtual point within a workspace. The control system is further configured to determine a first motion to move a first instrument supported by the repositionable assembly and determine movement of the virtual point resulting from the first motion. The control system is further configured to determine a second motion based on the movement of the virtual point and execute the second motion to reconfigure the repositionable assembly.

Description

REPOSITIONING A SUPPORTING STRUCTURE OF A COMPUTER-ASSISTED SYSTEMCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of the filing date of U.S. Provisional Patent Application 63 / 701,388 filed on September 30, 2024, which is hereby incorporated by reference herein in its entirety.BACKGROUNDField of Invention

[0002] The present invention generally provides improved computer-assisted devices, systems, and methods.Overview

[0003] Computer-assisted systems can be used to perform a task at a worksite. Example computer-assisted systems include industrial and recreational robotic systems. Example computer-assisted systems also include medical robotic systems used in procedures for diagnosis, non-surgical treatment, surgical treatment, etc. The computer-assisted system may include one or more robotic manipulators to manipulate instruments. An instrument may be an instrument for performing the task. An instrument may also be an instrument for viewing the performing of the task. The computer-assisted system may be equipped with any number of instruments of any type.

[0004] During use of the computer-assisted system, one or more of the instruments may be articulated. For example, one or more instruments may be articulated to manipulate or otherwise interact with the worksite, or, within a workspace at the worksite. Similarly, one or more instruments may be articulated to update the field of view available for viewing the task.

[0005] A field of view may visualize a region outside a reachable space of one or more instruments. In other words, an instrument may not be able to interact with a region of the workspace visualized in the field of view. Improved techniques for operating computer- assisted systems that adjust the reachable space of one or more instruments to coincide with the field of view.SUMMARY

[0006] In general, in one aspect, one or more embodiments relate to a computer- assisted system including a repositionable assembly configured to support and move one ormore instruments. The computer-assisted system further includes a control system including one or more processors and communicatively coupled to the repositionable assembly. The control system is configured to determine a virtual point within a workspace. The control system is further configured to determine a first motion to move a first instrument supported by the repositionable assembly and determine movement of the virtual point resulting from the first motion. The control system is further configured to determine a second motion based on the movement of the virtual point and execute the second motion to reconfigure the repositionable assembly.

[0007] In general, in one aspect, one or more embodiments relate to a method for controlling a computer-assisted system, the method performed by a control system of the computer-assisted system. The method including: determining a virtual point within a workspace; determining a first motion to move a first instrument supported by a repositionable assembly of the computer-assisted system; determining a movement of the virtual point resulting from the first motion; determining a second motion based on the movement of the virtual point; and executing the second motion to reconfigure the repositionable assembly.

[0008] In general, in one aspect, one or more embodiments relate to a non-transitory machine-readable medium comprising a plurality of machine-readable instructions executed by one or more processors associated with a computer-assisted system. The plurality of machine-readable instructions causing the one or more processors to perform a method. The method including: determining a virtual point within a workspace; determining a first motion to move a first instrument supported by a repositionable assembly of the computer-assisted system; determining a movement of the virtual point resulting from the first motion; determining a second motion based on the movement of the virtual point; and executing the second motion to reconfigure the repositionable assembly.

[0009] Other aspects of the invention will be apparent from the following description and the appended claims.BRIEF DESCRIPTION OF DRAWINGS

[0010] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures may be represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. In the drawings:

[0011] FIG. 1 shows an example repositionable assembly in accordance with one or more embodiments.

[0012] FIG. 2A shows an example computer-assisted system in accordance with one or more embodiments.

[0013] FIG. 2B shows an example system in accordance with one or more embodiments.

[0014] FIG. 3 shows an example repositionable assembly in accordance with one or more embodiments.

[0015] FIGs. 4A and 4B show example instruments in accordance with one or more embodiments.

[0016] FIGs. 5A-5D show examples of the field of view of an imaging instrument and the reachable space of another instrument, in accordance with one or more embodiments.

[0017] FIGs. 6A-6C show examples of a show examples of determining a virtual point based on, at least in part, a first instrument supported a repositionable assembly, and reconfiguring the repositionable assembly based on the virtual point in accordance with one or more embodiments.

[0018] FIGs. 7A-7C show examples of determining a virtual point based on the pose of two or more instruments supported by a repositionable assembly, and reconfiguring the repositionable assembly based on the virtual point in accordance with one or more embodiments.

[0019] FIG. 8 shows a flowchart describing an example method for reconfiguring the repositionable assembly in accordance with a determined motion, for example, to reposition a distal portion of a proximal repositionable structure, in accordance with one or more embodiments.DETAILED DESCRIPTION

[0020] Specific embodiments of the disclosure will now be described in detail with reference to the accompanying figures. Like elements in the various figures are denoted by like reference numerals for consistency.

[0021] In the following detailed description of embodiments of the disclosure, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to one of ordinary skill in the art that the invention may be practiced without these specific details. In other instances, well-knownfeatures have not been described in detail to avoid unnecessarily complicating the description.

[0022] Throughout the application, ordinal numbers (e.g., first, second, third, etc.) may be used as an adjective for an element (i.e., any noun in the application). The use of ordinal numbers is not to imply or create any particular ordering of the elements, and is not to limit any element to being only a single element unless expressly disclosed, such as by the use of the terms “before”, “after”, “single”, and other such terminology. Rather, the use of ordinal numbers is to distinguish between the elements. By way of an example, a first element is distinct from a second element, and the first element may encompass more than one element and succeed (or precede) the second element in an ordering of elements.

[0023] This disclosure describes various devices, elements, and portions of computer- assisted systems and elements in terms of their state in three-dimensional space. As used herein, the term “position” refers to the location of an element or a portion of an element (c.g, three degrees of translational freedom in a three-dimensional space, such as along Cartesian x-, y-, and z-coordinates). As used herein, the term “orientation” refers to the rotational placement of an element or a portion of an element (c.g, three degrees of rotational freedom in three-dimensional space, such as about roll, pitch, and yaw axes, represented in angle-axis, rotation matrix, quaternion representation, and / or the like). As used herein, and for a device with a kinematic series, such as with a repositionable structure with a plurality of links coupled by one or more joints, the term “proximal” refers to a direction toward a base of the kinematic series, and “distal” refers to a direction away from the base along the kinematic series.

[0024] As used herein, the term “pose” refers to the multi-degree of freedom (DOF) spatial position and orientation of a coordinate system of interest attached to a rigid body. In general, a pose includes a pose variable for each of the DOFs in the pose. For example, a full 6-DOF pose for a rigid body in three-dimensional space would include 6 pose variables corresponding to the 3 positional DOFs (e.g., x, y, and z) and the 3 orientational DOFs (e.g., roll, pitch, and yaw). A 3-DOF position only pose would include only pose variables for the 3 positional DOFs. Similarly, a 3-DOF orientation only pose would include only pose variables for the 3 rotational DOFs. Further, a velocity of the pose captures the change in pose over time (e.g., a first derivative of the pose). For a full 6-DOF pose of a rigid body in three-dimensional space, the velocity would include 3 translational velocities and 3 rotational velocities. Poses with other numbers of DOFs would have a corresponding number of velocities translational and / or rotational velocities.

[0025] Aspects of this disclosure are described in reference to computer-assisted systems, which can include devices that are teleoperated, externally manipulated, autonomous, semiautonomous, and / or the like. Further, aspects of this disclosure are described in terms of an implementation using a teleoperated surgical system, such as the da Vinci® Surgical System commercialized by Intuitive Surgical, Inc. of Sunnyvale, California. Knowledgeable persons will understand, however, that inventive aspects disclosed herein may be embodied and implemented in various ways, including teleoperated and nonteleoperated, and medical and non-medical embodiments and implementations. Implementations on da Vinci® Surgical Systems are merely exemplary and are not to be considered as limiting the scope of the inventive aspects disclosed herein. For example, techniques described with reference to surgical instruments and surgical methods may be used in other contexts. Thus, the instruments, systems, and methods described herein may be used for humans, animals, portions of human or animal anatomy, industrial systems, general robotic, or teleoperated systems. As further examples, the instruments, systems, and methods described herein may be used for non-medical purposes including industrial uses, general robotic uses, sensing or manipulating non-tissue work pieces, cosmetic improvements, imaging of human or animal anatomy, gathering data from human or animal anatomy, setting up or taking down systems, training medical or non-medical personnel, and / or the like. Additional example applications include use for procedures on tissue removed from human or animal anatomies (with or without return to a human or animal anatomy) and for procedures on human or animal cadavers. Further, these techniques can also be used for medical treatment or diagnosis procedures that include, or do not include, surgical aspects.

[0026] Referring now to the drawings, in which like reference numerals represent like parts throughout the several views, FIG. 1 shows an example repositionable assembly 100, in accordance with one or more embodiments.

[0027] FIG. 1 illustrates an example repositionable assembly 100 of a computer- assisted system. The repositionable assembly 100 includes a proximal repositionable structure 106 and one or more distal repositionable structures 102, 104, according to various embodiments. As shown in FIG. 1, a repositionable assembly 100 includes, without limitation, a proximal repositionable structure 106 that physically supports one or more distal repositionable structures (e.g., a first distal repositionable structure 102 and a second distal repositionable structure 104). The first distal repositionable structure 102 is configured to support a first instrument 122, and the second distal repositionable structure 104 is configured to support a second instrument 124. In various embodiments, each of the proximalrepositionable structure 106, the first and second distal repositionable structures 102, 104, and the first and second instruments 122, 124 can include any number of joints 144 of any type, and any number of links 142 of any geometry. While FIG. 1 shows a proximal repositionable structure 106 supporting two distal repositionable structures 102, 104 configured to support instruments 122 and 124, respectively, the proximal repositionable structure 106 can support any number of distal repositionable structures, and the distal repositionable structures 102, 104 can each support any number of instruments. Furthermore, the first instrument 122 and / or the second instrument 124 may include any number of links 142 and any number of joints 144. While FIG. 1 illustrates instrument 122 as an instrument with jawed end effectors and instrument 124 as an imaging instrument, such illustration is merely illustrative. In particular, the distal repositionable structures 102 and 104 may support any instrument type.

[0028] The combination of the first instrument 122 and the first distal repositionable structure 102 may have the same number of joints as the combination of the second instrument 124 and the second distal repositionable structure 104. Alternatively, as shown in FIG. 1, the combination of the first instrument 122 and the first distal repositionable structure 102 may have fewer joints than the combination of the second instrument 124 and the second distal repositionable structure 104.

[0029] In some embodiments, the motion of each of the proximal repositionable structure 106, first distal repositionable structure 102, first instrument 122 with jawed end effectors (not labeled), second distal repositionable structure 104, and second instrument 124 with an imaging device (not labeled) is relative to a corresponding reference. The corresponding references can be the same reference, or be different references. A reference can be, for example and without limitation, a reference point, a reference line or other geometric feature, a reference frame, etc. The reference can be fixed to the environment (e.g., a point, geometric feature, or frame of reference fixed to the environment or the earth; such a reference frame can be called a “world frame”), to a subject of a procedure such as a workpiece or part of a patient (e.g., a point, geometric feature, or frame of reference fixed to a patient feature and / or the like; such a reference frame can be called a “subject frame”), to a base of the robotic system (e.g., a base point, a base plane, frame of reference of the repositionable assembly or some other part of the robotic system), and / or the like. In some embodiments, the motions of the proximal repositionable structure 106, first distal repositionable structure 102, first instrument 122, second distal repositionable structure 104, and / or second instrument 124 are determined, controlled, or sensed relative to a samereference, or to different references. For example, the motion of the proximal repositionable structure 106 could be relative to a world frame while the motion of the first distal repositionable structure 102 and first instrument 122 could be relative to a reference point or reference frame fixed to the proximal repositionable structure 106.

[0030] In the example shown in FIG. 1, the bases of first distal repositionable structure 102 and second distal repositionable structure 104 are attached to a distal portion of the proximal repositionable structure 106, and motion of the proximal repositionable structure 106 moves the bases of first distal repositionable structure 102 and second distal repositionable structure 104. This “caused motion” of the bases of first distal repositionable structure 102 and second distal repositionable structure 104 can move distal portions of first distal repositionable structure 102 and / or second distal repositionable structure 104, and of any instruments or other elements attached to first distal repositionable structure 102 and second distal repositionable structure 104. In some embodiments, a caused motion (e.g., of the first distal repositionable structure 102 and first instrument 122 or of the second distal repositionable structure 104 and second instrument 124) is determined, responded to, or sensed relative to the same or a different reference as used for the motion of the proximal repositionable structure 106.

[0031] FIG. 2A illustrates an example computer-assisted system 200, according to various embodiments. As shown in FIG. 2A, the computer-assisted system 200 includes, without limitation, a repositionable assembly 210 and a user input system 250. In a teleoperation scenario, an operator (not shown) uses the user input system 250 to operate the repositionable assembly 210, such as in a leader-follower configuration (also often called teleoperation configuration or master-slave configuration in industry) of the computer- assisted system 200. In the leader-follower configuration, the user input system 250 is the leader, and the repositionable assembly 210 is the follower of the leader-follower configuration.

[0032] The repositionable assembly 210 can be used to introduce a set of instruments (not shown here; discussed below with reference to FIGs. 4A and 4B) to a work site through a port or entry guide 230 (a cannula is shown) inserted in an aperture. In a medical scenario, the work site can be on or within a body cavity of a patient, and the aperture can be a minimally invasive incision or a natural body orifice. When used, the port or entry guide 230 can be free-floating, held in place by a fixture separate from the repositionable assembly 210, or held by an entry guide supporting link 222 or other part of the repositionable assembly 210. The distal portion of the proximal repositionable structure, also referred to as amanipulator-supporting link 224 is coupled to additional joints and links 214, 220 of the repositionable assembly 210, and these additional joints and links 214, 220 are mounted on a base 212.

[0033] In accordance with one or more embodiments, FIG. 2A depicts a set of distal repositionable structures 226 coupled to the manipulator-supporting link 224. Each of the distal repositionable structures 226 includes a carriage (or other instrument-coupling link) configured to couple to an instrument, and each of the distal repositionable structures 226 include one or more joint(s) that can be driven to move the carriage. For example, a distal repositionable structure 226 can include a prismatic joint that, when driven, linearly moves the carriage and any instrument(s) coupled to the carriage. In some embodiments, this linear motion is along an insertion axis, as further described below with reference to FIGs. 4A and 4B. In this configuration the elements of the repositionable assembly 210 that are proximal to the distal repositionable structures 226 may be understood as the proximal repositionable structure as previously described in reference to FIG. 1.

[0034] In some embodiments, the additional joints and additional links 214 and 220 are used to position the port 230 at the aperture or another location. FIG. 2 A illustrates a prismatic joint for vertical adjustment (as indicated by arrow “A”) and a rotary joints for horizontal adjustment (as indicated by arrow “B”). In some embodiments, drivable joints are used to robotically pivot the port 230 (and the instruments disposed within it at the time) in yaw, pitch, and roll angular rotations about a remote center of motion as indicated by arrows C, D, and E, respectively. In some examples, the drivable joints of the plurality of joints of the repositionable assembly 210 provide redundant degrees of freedom, and coordinated motion of the drivable joints can cause part of the proximal and / or distal repositionable structure(s) to pivot about a software-centered remote center of motion (SWC). The location of the SWC can be moved relative to the base 212 part of the proximal repositionable structure and / or distal repositionable structure(s) 226 and is enabled by coordinated motion of the drivable joints. In some examples, the repositionable assembly 210 has a hardware remote center (HWC) that is maintained through the movement of one or more joints of the repositionable assembly 210 (e.g., a specific set of joints) without coordinated motion of the joints. In some examples, the repositionable assembly 210 includes drivable joints that provide redundant degrees of freedom that enable the repositionable assembly 110 to pivot part of the proximal and / or distal repositionable structure about a point other than the HWC and can switch between pivoting about a HWC or about a SWC. In review, these jointsproviding adjustments A, B, C, D, and E, may be considered part of the proximal repositionable structure as previously described in reference to FIG. 1.

[0035] In some embodiments, actuation of the degrees of freedom provided by joint(s) of the instrument(s) is provided by actuators disposed in, or whose motive force (e.g., linear force or rotary torque) is transmitted to, the instrument(s). Examples of actuators include rotary motors, linear motors, solenoids, and / or the like. The actuators drive transmission elements in the manipulators and / or in the instruments to control the degrees of freedom of the instrum ent(s). For example, the actuators can drive rotary discs of the distal repositionable structure(s) that couple with rotary discs of the instrument(s), where driving the rotary discs of the instruments drives transmission elements in the instrument that couple to move the joint(s) of the instrument, or to move the end effector(s) of the instrument, as further discussed below with reference to FIGs. 4A and 4B. Accordingly, the degrees of freedom of the instrument(s) are controlled by actuators that drive the instrument(s) in accordance with control signals determined based on inputs from the associated input devices (e.g., input devices 252 of the user input system 250). The control signals are determined in order to cause instrument motion or other actuation as indicated by movement of the input control devices or any other control signal. Furthermore, in some embodiments, appropriately positioned sensors, e.g., encoders, potentiometers, and / or the like, are provided to enable measurement of indications of the joint positions, or other data that can be used to derive joint position, such as joint velocity. The actuators and sensors are disposed in, transmit to, and / or receive signals from the distal repositionable structure(s) 226.

[0036] While a particular configuration of the repositionable assembly 210 is shown in FIG. 2A, those skilled in the art will appreciate that embodiments of the disclosure can be used with any design of repositionable assembly. For example, a repositionable assembly can have any number and any types of degrees of freedom, may or may not be configured to couple to a port, use a port other than a cannula, and / or other configuration different from what is shown in FIG 2 A.

[0037] In the embodiments shown in FIG 2A, the user input system 250 includes one or more input devices 252 operated by the operator (not shown). The one or more input devices 252 are contacted and manipulated by the hands of the operator, with one input device for each hand. Examples of such hand-input-devices include any type of device manually operable by human user, e.g., joysticks, trackballs, button clusters, and / or other types of haptic devices typically equipped with multiple degrees of freedom. Additionally, in some embodiments, position, force, and / or tactile feedback devices (not shown) are employedto transmit position, force, and / or tactile sensations from the instruments back to the operator's hands through the input devices 252.

[0038] The input devices 252 are supported by the user input system 250 and are shown as mechanically grounded, and in other implementations may be mechanically ungrounded. An ergonomic support 256 is provided in some implementations. For example, FIG. 2A shows an ergonomic support 256 including forearm rests on which the operator may rest his or her forearms while manipulating the input devices 252. In some examples, the operator performs tasks at a work site near the repositionable assembly 210 during a medical procedure by controlling the repositionable assembly 210 using the input devices 252. In some examples, a single input device 252 is used to control the repositionable assembly 210. In some examples, two input devices 252 are virtually linked such that movement in one input device is mimicked in the other, and / or that the relative position and orientation of the two input devices 252 can control different degrees of freedom of the repositionable assembly 210 and supported elements. For example, two virtually linked input devices 252 can be rotated about a center point between the two input devices 252 (e.g., like the movement of a steering wheel or handlebar), and this rotation can be mapped (e.g., to control) a degree of freedom of the repositionable assembly 210 and / or supported elements (e.g., roll or rotation of an instrument).

[0039] In some implementations, the input devices 252 consist of a kinematic series, such as with a repositionable structure with a plurality of links coupled by one or more joints. In general, sensors (e.g., encoders) are coupled to the components or joints of an input device to detect the position (and / or velocity, acceleration) of the components or joints throughout their respective degrees of freedom. Thus, the pose of an input device can be defined by the position and / or orientation of each of its components or joints along with a knowledge of the geometry and disposition of any interconnecting links between joints of the input device. The pose of the input device (or information regarding the position and orientation of each of its components and / or joints can be stored in a variety of mathematical or computational data structures such as a tensor. An input device consisting of a kinematic series may be configured to translate or rotate according to one or more degrees of freedom.

[0040] A display unit 254 is included in the user input system 250. The display unit 254 displays images for viewing by the operator. The display unit 254 provides the operator with a view of the workspace with which the repositionable assembly 210 interacts. The view can include, for example, stereoscopic images or three-dimensional images to provide a depth perception of the workspace and the instrum ent(s) of the repositionable assembly 210in the workspace. The display unit 254 can be moved in various degrees of freedom to accommodate the operator’s viewing position and / or to provide control functions. Where a display unit (such as the display unit 254 is also used to provide control functions, such as to command the repositionable assembly, the display unit also includes an input device (e.g., another input device 252).

[0041] When using the user input system 250, the operator can sit in a chair or other support in front of the user input system 250, position his or her eyes to see images displayed by the display unit 254, grasp and manipulate the input devices 252, and rest his or her forearms on the ergonomic support 256 as desired. In some implementations, the operator can stand at the workstation or assume other poses, and the display unit 254 and input devices 252 may differ in construction, be adjusted in position (height, depth, etc.), etc.

[0042] FIG. 2B illustrates an example system 270, according to various embodiments. The system 270 corresponds to the computer-assisted system 200 and includes one or more computing systems 272. A computing system 272 includes a processing system and is used to process input provided by the user input system 250, e.g., from the input device(s) 252 manipulated by an operator. In some embodiments, a computing system 272 is further used to provide an output, e.g., a video image to the display unit 274. Examples of display unit 274 include LCDs, LEDs, organic LED displays, projectors, etc. In some embodiments, one or more computing systems 272 are used to control the repositionable assembly 210.

[0043] In one or more embodiments, the computing system(s) 272 executes one or more control methods. The control methods include instructions for controlling one or more components of the repositionable assembly 210. In one or more embodiments, joint movements of the repositionable assembly 210 are controlled by one or more control methods driving one or more joints using actuators of the repositionable assembly 210, the joint movements being calculated by a processor of a processing system of the computing system(s) 272. The control methods process control signals from the user input system 250 or elsewhere, and / or sensor signals (e.g., positional encoder data from joint position sensors, image data from image instruments such as ultrasonic probes or cameras or endoscopes, and / or the like), to calculate commands for the joint actuators.

[0044] In some embodiments, the control methods perform at least some of the calculations of the joint commands using vectors and / or matrices, some of which have elements corresponding to positions, velocities, and / or forces / torques of the joints. The range of alternative joint configurations available to the control methods can be conceptualized as a joint space. For example, in some embodiments, the joint space has as many dimensions asthe repositionable assembly has degrees of freedom, and a particular configuration of the repositionable assembly represents a particular point in the joint space, with each coordinate corresponding to a joint state of an associated joint of the repositionable assembly.

[0045] As used herein, the term “state” of a joint or multiple joints refers to the control variables associated with the joint or the multiple joints, respectively. For example, the state of an angular joint refers to the angle defined by that joint within its range of motion, and / or to the angular velocity (or speed or direction) of the joint. Similarly, the state of an axial or prismatic joint refers to the joint's axial or linear position, and / or to its axial or linear velocity (or speed or direction). While one or more of the control methods described herein include position controllers, they often also have velocity control aspects. Alternative embodiments can rely primarily or entirely on velocity controllers, force controllers, acceleration controllers, and / or the like without departing from the disclosure. Various aspects of control systems that can be used in such devices are described in U.S. Pat. No. 6,699,177, which is incorporated herein by reference. In general, as long as the movements described are based on the associated calculations, the calculations of movements of the joints and movements of an end effector described herein are performed using a position control technique, a velocity control technique, an acceleration control technique, a force or torque control technique, a combination of some or all of the foregoing, and / or the like.

[0046] In some embodiments, the control modes include one or more other types of control modes. For example, during a robotic task being performed under the control of input devices 252 operated by a user, various joints of the repositionable assembly can be commanded to a same position and controlled to maintain static positions. However, in another control mode, one or more of the joints can be commanded to be “floating,” and facilitate motion of that joint due to externally applied force. For example, a joint held in place by a brake can be floated by partially or entirely releasing the brake. An example of such a joint includes a passive joint held in place by an electromagnetic brake. As another example, a joint driven by actuator(s) can be held in place by commanding the actuator(s) to hold the joint position and be floating by updating the command to the actuator(s) to the then- current position, velocity, and / or acceleration of the joint. As a result, a floating joint is readily reconfigured by an externally applied force or torque, without a control algorithm and / or a braking force seeking to counteract the reconfiguration caused by sufficient externally applied force or torque. In some embodiments, a floating joint is further controlled to exhibit other characteristics or provide additional responses, such as to provide a certain type or level of damping response. A floating joint can still be braked, actuated, or otherwisemanaged for friction or gravity compensation. Such compensation can be provided by, for example and without limitation, passive springs, actively driven actuators, and / or the like. Further, in some embodiments, joints that are not moved by actuators can still be gravity compensated, friction compensated, dampened, and / or the like by actuators.

[0047] In various embodiments, multiple different control modes are combined during operation of the repositionable assembly. For example, some joints could be controlled to maintain position and resist or rebound from attempted external articulation of those joints, while other joints could be controlled to be floating and facilitate external articulation of those other joints. Parameters such as joint position, velocity, or acceleration of the joints are detected by joint sensors. The sensor signals are used to provide kinematic information of the repositionable assembly.

[0048] The architecture of the control methods used for controlling the repositionable assembly can be of any appropriate form. As a specific example, the control architecture can be hierarchical, and could include a high-level controller and multiple joint controllers. A commanded movement is received by the high-level controller in, for example, a Cartesiancoordinate space (referred to herein as Cartesian-space). The commanded movement could be, for example, based on a movement command (e.g., in the form of a position and / or velocity) received from the user input system 250, or any other system that provides a movement command. The commanded movement is converted into commanded joint positions or joint velocities (e.g., linear or angular joint positions, linear or angular joint velocities). In some embodiments, the conversion is performed using an inverse kinematics algorithm. Subsequently, the joint controllers convert the received commanded joint positions or velocities into commanded currents to drive the actuators producing joint movements. The joint movements together produce a repositionable assembly movement that reflects the commanded movement.

[0049] In some embodiments, a joint controller controls a joint position. In some embodiments, the joint controller controls other variables such as joint velocity and / or joint force (linear force or angular torque). A joint controller receives a feedback signal in the form of a sensed joint state from an associated joint sensor, which it can use for closed-loop control. The sensed joint state includes, for example and without limitation, a joint position, a joint velocity (or component of velocity such as speed or direction), a joint acceleration (or component of acceleration), and / or the like, representing the joint movement. The sensed joint state is derived from the signals obtained from the joint sensor. A joint sensor can be, for example, an encoder, a potentiometer, an accelerometer, a hall effect sensor, and / or thelike. In some embodiments, a state observer or estimator (not shown) is used. Each joint controller can implement any appropriate control scheme, such as a proportional integral derivative (PID), proportional derivative (PD), full state feedback, sliding mode, and / or various other control schemes, without departing from the disclosure.

[0050] In one or more embodiments, the control methods further perform at least one of the steps described in FIG. 8 below.

[0051] A computing system 272 may include, without limitation, one or more computer processors, non-persistent storage (e.g., volatile memory, such as random access memory (RAM), cache memory), persistent storage (e.g., a hard disk, an optical drive such as a compact disk (CD) drive or digital versatile disk (DVD) drive, a flash memory, etc.), a communication interface (e.g., Bluetooth interface, infrared interface, network interface, optical interface, etc.), and / or numerous other elements and functionalities. In some embodiments, a computer processor of a computing system 272 is an integrated circuit for processing instructions. For example, the computer processor can be one or more cores or micro-cores of a processor.

[0052] In some embodiments, a communication interface of a computing system 272 includes an integrated circuit for connecting the computing system 272 to a network (not shown) and / or to another device, such as another computing system 272. Further, in some embodiments, the computing system 272 includes one or more output devices, such as a display unit 274, a printer, a speaker, external storage, or any other output device. Software instructions in the form of computer readable program code to perform embodiments of the disclosure are stored, in whole or in part, temporarily or permanently, on non-transitory computer readable medium. Specifically, the software instructions correspond to computer readable program code that, when executed by a processor(s), is configured to perform one or more embodiments of the disclosure. In some embodiments, a computing system 272 is connected to or configured to be a part of a network. The network may include multiple nodes. Each node corresponds to a different computing system, group of computing systems, group of nodes, and / or the like.

[0053] In some embodiments, the repositionable assembly 210 couples to an instrument when used to perform a procedure. The instrument can include an imaging device, e.g., an endoscope or an ultrasonic probe, usable to capture images of the workspace and output the captured images to an auxiliary system 280. In some embodiments, the auxiliary system 280 processes the captured images using one or more image processing techniques prior to any subsequent display. For example, the auxiliary system 280 canoverlay the captured images with a virtual control interface prior to displaying the combined images to the operator via the user input system 250. In some embodiments, one or more separate display units 274 are coupled with a computing system 272 and / or the auxiliary system 280 for local and / or remote display of images, such as images of the procedure site or other related images.

[0054] FIG. 3 illustrates another example repositionable assembly 300 of a computer- assisted system such as a robotic system, according to various embodiments. As shown in FIG. 3, a repositionable assembly 300 includes, without limitation, a proximal repositionable structure 306 that forms a common mechanical base for a first distal repositionable structure 312 and a second distal repositionable structure 314. The first distal repositionable structure 312 supports a first instrument 302, and the second distal repositionable structure 314 supports a second instrument 304. Each of the first distal repositionable structure 312, second distal repositionable structure 314, proximal repositionable structure 306, the first instrument 302, and second instrument 304 includes any number of joints (e.g., joints 344 and 346) of any type and / or any number of links (e.g., links 342) of any geometry.

[0055] As shown in FIG. 3, the first instrument 302 is equipped with a first end effector 322 and the second instrument 304 is equipped with a second end effector 324. As described below, various types of end effectors can be used. In some implementations, the end effector is considered part of an instrument. In such instances, an instrument can be defined or categorized based on its end effector.

[0056] As shown in FIG. 3, the proximal repositionable structure 306 provides a movable support for the first distal repositionable structure 312 and second distal repositionable structure 314. Further, in the example of FIG. 3, the first distal repositionable structure 312 and second distal repositionable structure 314 include prismatic joints 346 that enable translational movement of the first instrument 302 and the second instrument 304 relative to the proximal repositionable structure 306. While two distal repositionable structures (the first distal repositionable structure 312 and the second distal repositionable structure 314) are shown in FIG. 3, any number of distal repositionable structures can be included in the repositionable assembly 300.

[0057] In some embodiments, the repositionable assembly 300 is part of a medical robotic system. For example, the repositionable assembly 300 can be configured as a tableside-installed medical robotic system. The proximal repositionable structure 306 could be attached to a base of a surgical or examination table. Further, the medical robotic system could include one or more additional sets of drivable joints with the same or a differentdesign. For example, the repositionable assembly 300 can be installed on one side of the table, and a same or different repositionable assembly can be installed on the same side, or another side, of the table.

[0058] FIG. 4A illustrates an example instrument 400 (also referred to herein as an instrument 400), according to various embodiments. The instrument 400 in Figure 4A includes, without limitation, a shaft 410, and an end effector located at a first end of the instrument 400. A housing 430, arranged to releasably couple the instrument 400 to a distal repositionable structure (shown, for example, in FIG 2A), is located at a second end of the instrument 400. In some embodiments, the shaft 410 is rotatably coupled to the housing 430 to enable angular displacement of the shaft 410 relative to the housing 430, as indicated by arrows 448. In contrast, in some embodiments, the shaft 410 is not rotatably coupled to the housing 430 and the shaft 410 cannot be angularly displaced relative to the housing 430.

[0059] Various types of end effectors 440 can be used. For example, the end effector 440 can include one finger, two fingers (e.g., jaws 442 that may open and close), or three or more fingers. Examples of end effectors include, but are not limited to, scissors, forceps, staplers, cutting and cautery instruments, and / or the like. As another example, an end effector can further include an imaging device, e.g., an endoscope or an ultrasonic probe, to capture images of the workspace.

[0060] In some embodiments, an end effector 440 is actuated by transmission elements (e.g., cables, metal bands, screws, tubes, push rods, etc.) that connect parts of the instrument to drive elements (e.g., pulleys, capstans, spools, nuts, linear slides, or the like) (not shown) in the housing 430. Movement (e.g., translation or rotation) of the drive elements thereby controls the position of the end effector, or other degrees of freedom such as jaw opening, such that the end effector may translate or rotate, the jaws may open and close, and / or the like. In some embodiments, upon coupling of an instrument 400 on a distal repositionable structure, the drive elements engage with actuators of the distal repositionable structure, such as by engaging with transmission elements coupled to the actuators. As an example, a description of the control of an instrument like the instrument 400 can be found in U.S. Pat. No. 6,394,998, entitled “Surgical Tools for Use in Minimally Invasive Telesurgical Applications,” which is incorporated herein by reference.

[0061] In the example shown in FIG. 4 A, the joints of the instrument 400 include, without limitation, a wrist 420 proximal to the end effector 440 and two shaft offset joints 422, 424 proximal to the wrist 420. The wrist 420 may enable rotation of the end effector 440 in one or more directions. The shaft offset joints 422, 424 can enable, for example, atranslational offset 426 of the end effector 440 relative to the insertion axis 412 using the additional link serially coupled between the instrument shaft 410 and the end effector 440, in addition to the rotating provided by the wrist 420. The shaft offset joints 422, 424 may, thus, increase the workspace reachable by the end effector 440 of the instrument 400. Like the end effector 440, the wrist 420 and the shaft offset joints 422, 424 may be actuated by control cables.

[0062] FIG. 4B illustrates an example instrument or instrument 450, according to various other embodiments. Instruments 400 and 450 can be used for robotic procedures such as robotic medical procedures (e.g., surgeries), in accordance with one or more embodiments.

[0063] The instrument 450 shown in FIG. 4B includes, without limitation, various elements of the instrument 400 shown in FIG. 4A and operates in a substantially similar manner to the instrument 400 shown in FIG. 4A. Specifically, the instrument 450 includes a shaft 460 and a wrist 470 proximal to an end effector 490. Further, the instrument 450 has an insertion axis 462 for insertion / retraction of the instrument 450. The instrument 450 also allows angular displacement of the shaft 460 relative to the housing 480 as indicated by the arrows 498. Unlike the instrument 400 in FIG. 4A, the instrument 450 is not equipped with shaft offset joints. Accordingly, the instrument 450 cannot achieve a translational offset of the end effector 440 relative to the insertion axis 462 as can the instrument 400. For example, the shaft 460 without shaft offset joints could be made more rigid, could be configured to allow the transmission of higher forces or torques, could be configured to transmit forces and torques with reduced friction, and / or the like, compared to a similar shaft that includes shaft offset joints (e.g., shaft 410). An example of an instrument that generally utilizes transmission of a higher forces compared to other instruments is a tissue stapler (“stapler”). Additionally, in various implementations, an instrument without shaft offset joints could be less costly, easier to service, maintain and / or clean than a comparable instrument with shaft offset joints. An instrument without shaft offset joints may be said to be “joggle-less” or have a reduced number of degrees of freedom relative to an instrument with shaft offset joints.

[0064] While FIGs. 4A and 4B show particular configurations of instruments, designed to engage with a particular type of distal repositionable structure, other configurations of instruments are within the scope of the disclosure. For example, embodiments of instruments 400 and 450 could have multi-degree-of-freedom wrists (e.g., pitch and yaw degrees of freedom), single-degree-of-freedom wrists (e.g, pitch or jaw), or nowrists. Also, various embodiments of instruments could have any suitable type of end effector including, for example, scissors, forceps, staplers, irrigation nozzles, hooks, scissors, blunt dissection instruments, needle drivers, imaging devices, and / or the like. Further, different housings can also be used to interface with different types of distal repositionable structure or different structures altogether (e.g., direct interface with the proximal repositionable structure).

[0065] The subsequently discussed figures illustrate a repositionable assembly that is controlled by a computer-assisted system to move or reposition the distal portion of a proximal repositionable structure. For example, the distal portion of the proximal repositionable structure can be repositioned about a remote center of motion. As another example, the distal portion of the proximal repositionable structure can be moved along an insertion axis of the repositionable assembly to alter the relative position of the distal portion to, say, an aperture. A prismatic joint of a distal repositionable structure can be actuated to move or reposition the distal repositionable structure and / or an attached instrument, e.g., in response to movement of the distal portion along the insertion axis.

[0066] The distal portion of the proximal repositionable structure can support, or serve as a common mechanical base (e.g., manipulator-supporting link) for one or more distal repositionable structures each configured to support one or more instruments. Thus, movement or repositioning of the distal portion of the proximal repositionable structure can move, or affect, supported instruments. Movement or repositioning of the distal portion of the proximal repositionable assembly can be effectuated through a reconfiguration of the repositionable assembly. For example, the state of one or more joints of the repositionable assembly can be adjusted (i.e., a reconfiguration) to reposition the distal portion of the proximal repositionable structure. Similarly, use of one or mor degrees of freedom of a distal repositionable structure can be considered under the configuration or reconfiguration of the repositionable assembly.

[0067] In some instances, the position and orientation of an instrument is maintained with respect to a world frame (i.e., using a reference fixed to the environment), e.g., through use of degrees of freedom of the instrument, in view of a reconfiguration of the repositionable assembly. An instrument with an end effector that has a position (and, in some instances, an orientation) that is maintained within or relative to a workspace (i.e., relative to a world frame) in view of other movements (e.g., repositioning of the proximal repositionable structure) may be said to be “anchored.” As an example, methods for coordinating movements of multiple instruments of a repositionable assembly are described in furtherdetail in International Patent Publication No. WO2022 / 046787A1, entitled “Method and System for Coordinated Multiple-Tool Movement Using a Drivable Assembly,” which is incorporated herein by reference. Anchoring of an instrument can include a change to one or more degrees of freedom or joints of the instrument. That is, during a reconfiguration of the repositionable assembly (e.g., repositioning the distal portion of a proximal repositionable structure) an anchored instrument can execute compensatory adjustments to maintain its position (and, in some instances, orientation) in the workspace (z.e., relative to a world frame). In some instances, anchoring is achieved using an instrument equipped with shaft offset joints as described with respect to FIG. 4A, where the shaft offset joints, in addition to other instrument joints such as a wrist and a rotatably coupled shaft, provide sufficient degrees of freedom to the instrument to maintain its position and orientation during reconfiguration of the repositionable assembly.

[0068] The subsequently discussed figures illustrate the field of view of an imaging instrument (i.e., an instrument with an end effector including an imaging device), or at least the determination of a virtual point, and a reachable space of one or more additional instruments supported by and manipulated with a repositionable assembly. In general, the reachable space of one or more instruments is associated with the position and / or pose of a proximal repositionable structure of the repositionable assembly. For example, in one or more embodiments, the proximal repositionable assembly supports one or more distal repositionable structures (e.g., manipulators) each configured to support one or more instruments. Further, the repositionable assembly can undergo a reconfiguration to move or reposition the distal portion of the proximal repositionable structure from which the one or more distal repositionable structures are supported. This “caused motion” of the distal repositionable structures can, in turn, cause motion of any instruments or other elements attached to distal repositionable structures. The instruments can further use their degrees of freedom to adjust their poses. Herein, the reachable space of one or more instruments is a space accessible to the distal portion(s) or end effector(s) of the one or more instruments using the degrees of freedom of the instruments and / or the distal repositionable structure(s). For example, an instrument with shaft offset joint and / or a wrist assembly can use those degrees of freedom to move within a workspace. As another example, a distal repositionable structure can be used to insert and retract an attached instrument into the workspace. And, in some instances, the proximal repositionable assembly can be reconfigured, e.g., to move the distal portion of the proximal repositionable assembly about a remote center, defined by the range of motion of the instruments. That is, in one or more embodiments, the reachablespace of an instrument can be defined by degrees of freedom of the instrument and / or degrees of freedom associated with, for example, the distal repositionable structure to which the instrument is attached. In some instances, the reachable space of an instrument may further consider one or more degrees of freedom of the proximal repositionable structure, e.g., to extend the reach (or exhibit “reach assist behavior”) without exceeding the scope of this disclosure. However, even in consideration of these cases, it may still be said that the reachable space of one or more instruments is associated with the position and / or pose of a proximal repositionable structure of the repositionable assembly. For example, reconfiguration of the repositionable assembly to move or reposition the distal portion of the proximal repositionable structure affects the reachable space of the supported instruments. One or more supported instrument may be anchored such that during a reconfiguration of the repositionable assembly (e.g., repositioning the distal portion of a proximal repositionable structure) an anchored instrument executes compensatory adjustments to maintain its position (and, in some instances, orientation) in the workspace (i.e., relative to a world frame), however, the reachable space of the instrument can be affected by the reconfiguration. In some instances, reconfiguration of the repositionable assembly moves the reachable space of an anchored instrument such that a boundary of the reachable space coincides with the position of the anchored instrument. In these instances, it may be said that the anchored instrument is at a range of motion limit where one or more of its degrees of freedom have realized a limit to maintain the position (and, sometimes, the orientation) of the instrument.

[0069] In one or more embodiments, the range of motion of an instrument can be realized without a user’s knowledge as to which degrees of freedom are used in the motion of the instrument. For example, in a teleoperation scenario, an operator using the user input system 250 to operate the repositionable assembly 210 can command motion of a distal portion of an instrument where the motion is realized using one or more of the degrees of freedom of the instrument, the distal repositionable structure, and the proximal repositionable structure. As will be illustrated in the following figures and the method as described in reference to FIG. 8, a distal portion of a repositionable assembly can be moved to reposition the reachable space of one or more instruments. In some embodiments, the adjusted position and orientation of the distal portion of the repositionable assembly is based on a field of view provided by an imaging instrument.

[0070] FIGs. 5A-5D show examples of possible fields of view, using an instrument equipped as an imaging device, and reachable spaces of one or more additional instruments supported by and manipulated with a repositionable assembly. In the examples, arepositioning of an instrument using a movement of a manipulator-supporting link proximal to two instruments is shown.

[0071] As shown in FIGs. 5 A-5D, a repositionable assembly includes a proximal repositionable structure, which is or includes a manipulator-supporting link 502 that supports multiple distal repositionable structures 550 and 552 coupled to multiple instruments 504 and 510. In other words, the manipulator-supporting link 502 forms a common mechanical base for the manipulators 550, and 552 that support the instruments 504 and 510. It is emphasized that the common mechanical “base” provided by the manipulator-supporting link 502 is distinct from the “base” 212 of the repositionable assembly. In some embodiments, the manipulator-supporting link 502 corresponds to the manipulator-supporting link of a proximal repositionable structure as previously introduced with reference to FIG 2A. That is, in some embodiments, the manipulator-supporting link can be considered the distal portion of a proximal repositionable structure. Hereafter, for concision, the distal repositionable structures 550 and 552 will be referred to as a first distal repositionable structure 550 and a second distal repositionable structure 552. The first distal repositionable structure 550 can correspond to the first distal repositionable structure 102, 312 of FIG. 1 and FIG. 3, respectively. Similarly, the second distal repositionable structure 552 can correspond to the second distal repositionable structure 104, 314 of FIG. 1 and FIG. 3, respectively. Likewise, instruments 504 and 510 are hereafter referred to as a first instrument 504 and a second instrument 510, where these instruments can correspond to the first instrument 122, 302 and second instrument 124, 304 of FIGs. 1 and 3, respectively. In the example of FIGs. 5A-5D, the first instrument 504 is an imaging instrument (in other words, an instrument with an end effector including an imaging device). The first instrument is associated with a field of view 506. Field of view is used herein as a general term intended to indicate the extent of the observable world that is “seen” by a sensor (e.g., a camera).

[0072] In the example of FIGs. 5A-5D, the first instrument 504 and second instrument 510 are inserted through a cannula 530 toward a workspace 598 containing a target 596, and the cannula 530 is inserted through an aperture 592 in a barrier 594. In a medical scenario, the barrier 594 could be a body wall of a patient, and the aperture 592 could be a minimally invasive incision or a natural body orifice of the patient, and the target 596 could be an anatomical structure of interest.

[0073] In one or more embodiments, the proximal repositionable structure can define an insertion axis 590. Movement of one or more joints of the proximal repositionable structure, for example, results in movement of the manipulator-supporting link 502. Whenthe manipulator-supporting link 502 is moved, the insertion axis 590 and portions of the first distal repositionable structure 550 and second distal repositionable structure 552 attached to the manipulator-supporting link 502 can also be moved. Such caused motion of the insertion axis 590, first distal repositionable structure 550, and second distal repositionable structure 552 can cause motion of the first instrument 504 and the second instrument 510. For example, if the first distal repositionable structure 550 and second distal repositionable structure 552 are held fixed in configuration, then the movement of the manipulatorsupporting link 502 also moves the first instrument 504 and the second instrument 510.

[0074] In one or more embodiments, the manipulator-supporting link 502 can be pivoted about a remote center of motion 540 (also called “remote center” 540). In the example shown in FIGs. 5A-5D, the repositionable assembly has been positioned, and / or is controlled, such that the remote center of motion 540 is located approximately centrally in the aperture 592.

[0075] FIGs. 5A-5D further illustrate a reachable space 507 of one or more supported instruments. As described above, the reachable space 507 of one or more instruments is the space accessible to the distal portion(s) or end effector(s) of the one or more instruments using the degrees of freedom of the instruments and / or the distal repositionable structure(s). In some instances, it may be said that the reachable space is a space enclosed by the range of motion of the instruments. The range of motion of an instrument can be provided by degrees of freedom of the instrument and also degrees of freedom associated with, for example, the distal repositionable structure to which the instrument is attached. For example, an instrument can use its degrees of freedom to adjust its pose where the reachable space 507 encloses the position of the end effector of the instrument in all of the instrument’s available poses (constraints may limit the number of available poses). FIGs. 5A-5D depict the reachable space 507 associated with the second instrument 510. As depicted in these figures, in general, the reachable space 507 can move with, or can be affected by, the position and orientation of the proximal repositionable structure (or, in other words, the pose of the repositionable assembly). That is, the reachable space 507 can move or be altered with movement of the manipulator-supporting link 502. This includes instances where the reachable space 507 considers at least some movement of the proximal repositionable structure and / or one or more distal repositionable structures (e.g., using degrees of freedom of the proximal repositionable structure for reach assist). That is, turning to the examples of FIGs. 5 A-5D, even in instances where the reachable space 507 encloses positions of the end effector 512 of the second instrument 510 where associated poses are achieved using at leastone degree of freedom external to the second instrument 510 (e.g., a degree of freedom of the proximal repositionable structure), the reachable space 507 can still be dependent on, or move with, movements of the proximal repositionable structure (e.g., manipulator supporting link). In other words, whether a position and orientation of an end effector of an instrument is achieved using degrees of freedom of the instrument, degrees of freedom of the distal or proximal repositionable structures, or both, the reachable space 507 generally tends to move with the distal portion of the proximal repositionable structure (e.g., manipulator-supporting link 502).

[0076] The reachable space 507 depicted in FIGs. 5A-5D is substantially conical, however this need not be the case. In general, the reachable space 507 can be asymmetrical, be bounded by non-differentiable surfaces, etc. Further, while the reachable space 507 of FIGs. 5A-5D is depicted as having vertex or origin at the remote center 540, this also need not be the case.

[0077] As discussed above, an instrument with an end effector that has a position (and, in some instances, an orientation) that is maintained within or relative to a workspace in view of other movements (e.g., pivoting of the manipulator-supporting link 502 about the remote center 540) may be said to be “anchored.” The reachable space 507 of one or more instruments can be constrained by one or more other instruments that are “anchored.” An example of a constraint on the repositioning of the manipulator-supporting link 502 due to an anchored instrument, and thus a constraint on the movement or repositioning of the reachable space, is shown in FIG. 6C.

[0078] As previously discussed, instruments can have various degrees of freedom. In the example of FIGs. 5A-5D, the second instrument 510 lacks shaft offset joints while the first instrument 504 includes shaft offset joints 508. Various instruments may comprise or lack joints for various degrees of freedom. For example, the first instrument 504 or the second instrument 510 could lack joints to support movement about a roll degree of freedom about a respective roll axis. As another example, an instrument may not include an articulated wrist. Also, the target 596 can be any kind of object (e.g., anatomical structure), and an instrument (e.g., second instrument 510) can be any kind of instrument equipped with an end effector suitable to interact with the target 596. For example, in a surgical scenario, the end effector could include forceps, and the target could include tissue.

[0079] In FIGs. 5A-5D, the first instrument 504 is an imaging instrument having a field of view 506. FIG. 5A depicts an instance where the field of view 506 and the reachable space 507 are substantially aligned or coincident. In one or more embodiments, an alignmentmetric can be computed for the field of view 506 and the reachable space 507. Consider a case where the field of view 506 is said to capture a first area and the reachable space encloses an equivalent second area. In one or embodiments, an alignment metric is computed as the intersection over union of the first area and the second area. Thus, in these instances, a field of view 506 and a reachable space 507 having an intersection over union score approaching a value of 1 are aligned. In other embodiments, an alignment metric is computed as the ratio of the intersection of the first area and the second area over the first area. That is, instances where the reachable space 507 encloses the field of view 506 may also be considered aligned. Notably, determination of an alignment metric is not required to execute one or more embodiments described herein. Thus, discussion of an alignment metric is to promote an understanding of an aligned field of view 506 and reachable space 507.

[0080] In accordance with one or more embodiments, the field of view 506 captured using the first instrument 504 is provided to an operator as a video or image, for example, on the display unit 254 included in the user input system 250. Thus, the field of view 506 provides the operator with a view of the workspace with which the repositionable assembly interacts. A benefit of a substantially aligned field of view 506 and reachable space 507 is that the portion of the workspace visualized or captured according to the field of view 506 is readily accessible by one or more instruments. For example, in FIG. 5A, the second instrument 510 is movable to regions of the workspace viewed by the first instrument 504.

[0081] FIG. 5B depicts an instance where the first instrument 504 using, for example, a wrist assembly of the first instrument 504, has been articulated to better view the target 596. That is, with respect to FIG. 5A, the first instrument 504 in FIG. 5B has been repositioned such that the field of view 506 captures or encloses the target 596. In the example of FIG. 5B, although the field of view 506 includes the target 596 the target 596 cannot be interacted with using the second instrument 510 as indicated by the target 596 residing outside of the reachable space 507 in FIG. 5B.

[0082] FIG. 5C depicts an instance where manipulator-supporting link 502 has undergone a pivoting motion 532 with respect to the remote center 540. During the pivoting motion 532 the first instrument 504 executed compensatory adjustments to maintain its position in the workspace whereas the second instrument 510 moved with the manipulatorsupporting link 502. In other instances, the second instrument 510 maintains its position (and / or orientation) in the workspace throughout a repositioning of the manipulatorsupporting link 502. In the example of FIG. 5C, the repositioned proximal repositionablestructure brought the reachable space 507 and the field of view 506 into alignment and further made the target 596 accessible by the second instrument 510.

[0083] FIG. 5D depicts an instance where the first instrument has again been repositioned without a movement or repositioning of the proximal repositionable structure (e.g., manipulator-supporting link 502). As seen in FIG. 5D, the field of view 506 and the reachable space 507 are not aligned.

[0084] As demonstrated in FIGs. 5A-5D, the repositionable assembly can be operated by the computer-assisted system to move or pivot the distal portion of the proximal repositionable structure (e.g., manipulator-supporting link 502), for example, about a remote center 540. Movement, or repositioning, of the distal portion of the proximal repositionable structure can move, or affect, the reachable space 507 of one or more supported instruments. It is noted that some of the one or more instruments may have a distal portion that remains fixed with respect to an absolute frame of reference during movement of the reachable space 507 by the repositionable assembly (i.e., anchored). That is, the degrees of freedom of the instruments themselves may be used to maintain an absolute position of the instruments even as their position relative to the reachable space 507 is altered through movement of the reachable space 507 itself by the repositionable assembly.

[0085] Embodiments of the disclosure relate to automatically adjusting the pose of the repositionable assembly, or, more specifically, the position and orientation of the distal portion of the proximal repositionable structure (i.e., automatic adjustment of the proximal repositionable structure). In some instances, the automatic adjustments of the pose of the repositionable assembly (e.g., to reposition the distal portion of the proximal repositionable structures) are performed to position the reachable space 507 of one or more instruments supported by the repositionable assembly. In some embodiments, automatic adjustments (i.e., a reconfiguration) of the pose of the repositionable assembly includes, or induces, a general alignment of the reachable space 507 with a field of view 506 produced by an imaging instrument. That is, the general alignment of the field of view 506 and the reachable space 507 is realized by reconfiguring the repositionable assembly (e.g., repositioning the distal portion of the proximal repositionable structure). As an example, the pose of a portion of the repositionable assembly (e.g., the proximal repositionable structure) can be automatically adjusted based on changes to a pose (e.g., position and / or orientation) of a distal portion of a first instrument (e.g., an imaging device, a camera) such that the automatic adjustments cause a reachable space of one or more other instruments to be moved based on changes to the pose of the first instrument. In other embodiments, and as described below,automatic adjustments of the pose of the repositionable assembly (e.g., adjustment of the proximal repositionable structure) are based on the positions (or poses), or relative positions (or relative poses), of two or more instruments supported by the repositionable assembly.

[0086] In accordance with one or more embodiments, automatic adjustment of the proximal repositionable structure is performed in a manner such that a distance, c, between a specified axis (e.g., insertion axis 590) and a virtual point is reduced. Thus, in one or more embodiments, a virtual point is determined within the workspace. The virtual point can be determined according to a placement procedure described in greater detail below.

[0087] Similar to FIGs. 5A-5C, FIGs. 6A-6C and 7A-7C depict a first instrument 504 supported by a first distal repositionable structure 550 and a second instrument 510 supported by a second distal repositionable structure 552 inserted through a cannula 530 toward a workspace 598. The cannula 530 is inserted through an aperture 592 in a barrier 594. Like elements are given the same numeric labels in FIGs. 6A-6C and FIGs. 7A-7C as in FIGs. 5A- 5C. To avoid cluttering of the figures and to promote clarity, numeric labels for some elements are omitted in FIGs. 6A-6C and FIGs. 7A-7C.

[0088] FIGs. 6A-6C depict the determination of a virtual point and a repositioning of the distal portion of the proximal repositionable structure (e.g., manipulator-supporting link 502) based on a distance, c, between the virtual point and a specified axis (e.g., insertion axis 590), where the virtual point is determined according to a first placement procedure. FIGs. 7A-7C depict a similar example as that of FIGs. 6A-6C, however, in the example of FIGs. 7A-7C the virtual point is determined according to a second placement procedure.

[0089] FIGs. 6A-6C depict a first instrument 504 as an imaging instrument and a second instrument 510. The first instrument 504 defines a field of view axis 604. In the given example, the first instrument is equipped with offset joints 508. Departing from FIGs 5A-5C, in FIGs. 6A-6C the second instrument is also provided with offset joints 609. FIG. 6A illustrates the determination of a virtual point 602 in the workspace according to a first placement procedure. In the first placement procedure the location of the virtual point 602 is given with respect, at least, the field of view axis 604. In accordance with one or more embodiments, the virtual point 602 is offset from the distal end of the first instrument 504 by a first offset 606, Ai, along the field of view axis 604. In one or more embodiments, the first offset 606 is set equal to the length of the most distal link of the first instrument 504, e.g., the link between the offset joints 508. The virtual point 602 can further be offset from the field of view axis 604 by a second offset 608, A2. In one or more embodiments, the second offset 608 is along a line orthogonal to the field of view axis 604 and intersecting the insertion axis590. In some implementations the second offset 608 is set equal to zero such that the virtual point 602 resides on the field of view axis 604. In other implementations the second offset 608 is equal to the first offset 606.

[0090] In the example of FIGs. 6A-6C the virtual point 602 is positioned relative to the position and orientation of the first instrument 504. Specifically, the position of the virtual point 602 in the workspace is given according to a first offset 606 and a second offset 608 that reference the field of view axis 604 defined by the first instrument 504, where the field of view axis 604 moves with the first instrument 504. FIG. 6B depicts an instance where the first instrument 504 has been repositioned such that the field of view 506 that it provides captures the target 596. As seen in FIG. 6B, the virtual point 602 has also been repositioned accordingly due to the motion of the first instrument 504.

[0091] FIG. 6B also depicts a distance 610, e, between the virtual point 602 and the insertion axis 590. The distance 610 between the virtual point 602 and the insertion axis 590 can be computed in a variety of ways. In one example, the distance 610 is the length of a line connecting the virtual point 602 and the insertion axis 590 where the line is orthogonal to the insertion axis 590. In another example, the distance 610 is the length of the shortest line that connects the virtual point 602 and the insertion axis 590 (z.e., orthogonality of the line and the insertion axis 590 is not required).

[0092] In accordance with one or more embodiments, automatic adjustment of the proximal repositionable structure is enacted by repositioning the distal portion of the proximal repositionable structure (e.g., manipulator-supporting link 502) to reduce the distance 610, e. FIG. 6C depicts an instance where the manipulator-supporting link 502 has undergone a pivoting motion 532 relative to the remote center 540 to reduce the distance 610 between the virtual point 602 and the insertion axis 590. In the example of FIG. 6C, the second instrument 510 is anchored during the pivoting motion 532. That is, during the pivoting motion 532 the second instrument 510 executed compensatory adjustments to maintain its position in the workspace. Further, in the example depicted by FIG. 6C, the second instrument 510 is at a boundary of the reachable space 507 indicating that the second instrument 510 is at a limit of its range of motion. That is, in maintaining its position, the second instrument 510 has reached a limit in its range of motion due to the pivoting motion 532 of the manipulator-supporting link 502. Additional movement of the manipulatorsupporting link 502 to further reduce the distance 610 between the virtual point 602 and the insertion axis 590 would necessitate a change in the position of the second instrument 510 (i.e., the second instrument 510 would no longer remain anchored). In one or moreembodiments, repositioning of the distal portion of the proximal repositionable structure (e.g., pivoting motion 532) is constrained according to the anchoring requirements of any anchored instruments supported by the repositionable assembly (e.g., second instrument 510). As in the example of FIG. 6C, the pivoting motion 532 of the distal portion of the proximal repositionable structure has reduced the distance 610 between the virtual point 602 and the insertion axis 590 however the distance is non-zero and cannot be further reduced due to an anchoring requirement imposed by the second instrument 510. That said, the repositioning of the distal portion of the proximal repositionable structure by the pivoting motion 532 to reduce the distance 610 is advantageous because, as depicted in FIG. 6C, the field of view 506 is encompassed by the reachable space 507. Thus, in one or more embodiments, the field of view 506 and the reachable space 507 are considered aligned and the proximal repositionable structure is said to have been automatically adjusted (or, adjusted with respect to the imposed constraints).

[0093] In review, FIG. 6A depicts an instances where a virtual point 602 is determined based on the pose of the first instrument 504 (z.e., first placement procedure). Specifically, the first instrument 504 is an imaging instrument and the virtual point 602 is positioned within the workspace according to a first offset 606 and a second offset 608 with respect to the first instrument 504 and a field of view axis 604 of the first instrument 504. FIG. 6B depicts a first motion to move the first instrument 504 supported by the repositionable assembly. As seen, the first motion can affect the position of the virtual point 602 in the workspace. Thus, movement of the virtual point 602 is determined resulting from or based on the first motion. In response to movement of the virtual point 602, a second motion based on the movement of the virtual point 602 can be determined. The second motion can be executed to reposition the distal portion of the proximal repositionable structure (e.g., manipulator-supporting link 502). In one or more embodiments, and as depicted in FIG. 6C, the second motion can reduce the distance 610 between the virtual point 602 and the insertion axis 590. In other words, determining the second motion includes determining a pose of the proximal repositionable structure, and possibly one or more distal repositionable structures, that reduces the distance 610 subject to any given constraints, e.g., one or more anchored instruments.

[0094] Turning to FIGs. 7A-7C, FIGs. 7A-7C depict an example where the virtual point 602 is determined according to a second placement procedure. In the example of FIGs. 7A-7C, the first instrument 504 is not an imaging instrument. Similarly, the second instrument 510 is not an imaging instrument. In the second placement procedure the locationof the virtual point 602 is determined based on the poses of the first and second instruments 504, 510. Specifically, in the example of FIGs. 7A-7C, the virtual point 602 is determined to be the centroid of the positions of the first instrument 504 and the second instrument 510. FIGs. 7A-7C depict a connecting line 702 between wrists of the first and second instruments 504, 510. In this example, the centroid of the first and second instruments 504, 510 resides along and at the midpoint of the connecting line 702.

[0095] Consider the workspace as a three-dimensional space, the space referenced using a Cartesian coordinate system with x, y, and z axes. Then, and in accordance with one or more embodiments, the centroid of a set of N instruments, where N is an integer greater than or equal to one, is given asEQ. 1 where xc, yc, and zcare coordinates of the centroid in the x, y, and z axes, respectively, the xc, yc, and zccoordinates forming a triplet that defines the location of the centroid in the three-dimensional space, and x£,y£, and z£represent the x, y, and z coordinate of the ithinstrument, respectively.

[0096] In the example of FIGs. 7A-7C the virtual point 602 is positioned based on the poses of the first and second instruments 504, 510. Thus, if the first instrument 504, second instrument 510, or both, undergo a change in pose (e.g., motion, repositioning, etc.) the position of the virtual point 602 in the workspace can also change. FIG. 7B depicts an instance where the first instrument 504 has been repositioned. As seen in FIG. 7B, the virtual point 602 has also been repositioned accordingly due to the motion of the first instrument 504.

[0097] FIG. 7B also depicts a distance 610, e, between the virtual point 602 and the insertion axis 590. The distance 610 between the virtual point 602 and the insertion axis 590 can be computed in a variety of ways. In one example, and as depicted in FIG. 7B, the distance 610 is the length of a line connecting the virtual point 602 and the insertion axis 590 where the line is orthogonal to the insertion axis 590. In another example, the distance 610 is the length of the shortest line that connects the virtual point 602 and the insertion axis 590 (z.e., orthogonality of the line and the insertion axis 590 is not required).

[0098] In accordance with one or more embodiments, automatic adjustment of the proximal repositionable structure is enacted by repositioning the distal portion of theproximal repositionable structure (e.g., manipulator-supporting link 502) to reduce the distance 610, e. FIG. 7C depicts an instance where the manipulator-supporting link 502 has undergone a pivoting motion 532 relative to the remote center 540 to reduce the distance 610 between the virtual point 602 and the insertion axis 590. In the example of FIG. 7C, the first instrument 504 and the second instrument 510 are anchored during the pivoting motion 532. That is, during the pivoting motion 532 the first instrument 504 and the second instrument 510 execute compensatory adjustments to maintain their positions in the workspace. In the example of FIG. 6C, the proximal repositionable structure (e.g., manipulator-supporting link 502) has been repositioned such that the insertion axis 590 intersects the virtual point 602. A benefit of positioning the proximal repositionable structure in this way is that the reachable space 507 of the first and second instruments 504, 510 is centered, or substantially aligned with, the centroid of the instruments.

[0099] In review, FIG. 7A depicts an instances where a virtual point 602 is determined based on the poses of the first instrument 504 and the second instrument 510 (i.e., second placement procedure). Specifically, the virtual point 602 is determined to coincide with the centroid of the first instrument 504 and the second instrument 510. FIG. 7B depicts a first motion to move the first instrument 504 supported by the repositionable assembly. As seen, the first motion can affect the position of the virtual point 602 in the workspace. Thus, movement of the virtual point 602 is determined based on the first motion. In response to movement of the virtual point 602, a second motion based on the movement of the virtual point 602 can be determined. The second motion can be executed to reconfigure the repositionable assembly (e.g., proximal repositionable structure, manipulator-supporting link 502). In one or more embodiments, and as depicted in FIG. 67C, the second motion reduces the distance 610 between the virtual point 602 and the insertion axis 590. In other words, determining the second motion includes determining a pose of the repositionable assembly (e.g., to reposition the distal portion of the proximal repositionable structure) that reduces the distance 610 subject to any given constraints, e.g., one or more anchored instruments.Adjusting the pose the repositionable assembly can include adjustment, or movement, of one or more distal repositionable structures.

[0100] Additional placement procedures can be applied without departing from the scope of this disclosure. In some implementations, the virtual point 602 is determined relative to the insertion axis 590. For example, the virtual point 602 can be determined to reside at a predefined offset along the insertion axis 590 and another predefined offset from the insertion axis 590, e.g., toward a specified instrument such as an imaging instrument. Inthis case, the virtual point 602 can move with the insertion axis 590 and a distance 610 between the virtual point and a field of view axis 604 of an imaging instrument (e.g., first instrument 504 in FIG. 6A) can be determined. Thus, in accordance with one or more embodiments, the repositionable assembly can be reconfigured, or commanded to a new pose (e.g., to reposition the distal portion of the proximal repositionable structure), in response to a movement of the imaging instrument resulting in a non-zero value for the distance 610 between the virtual point 602 and the insertion axis 590. That is, in this case automatic adjustment or reconfiguration of the repositionable assembly is performed in a manner such that a distance, c, between a specified axis (the field of view axis 604) and a virtual point is reduced.

[0101] Continuing with the concept of additional placement procedures, in some implementations the virtual point 602 is determined to coincide with a centroid of a set of instruments selected by an operator of the repositionable assembly. For example, an operator may select or specify two instruments that are used to determine the centroid, and thus the virtual point 602, in a scenario where the repositionable assembly supports more than two instruments. Further, in some implementations, the virtual point 602 is determined to coincide with a centroid determined according to a weighting scheme (i.e., a weighted centroid) of one or more selected or specified instruments. Again, considering the workspace as a three-dimensional space referenced using a Cartesian coordinate system with x, y, and z axes the weighted centroid of a set of N selected instruments (A > 1) is given asEQ. 2 where xc, yc, and zcare coordinates of the weighted centroid in the x, y, and z axes, respectively, the xc, yc, and zccoordinates forming a triplet that defines the location of the weighted centroid in the three-dimensional space, x^yi, and ztrepresent the x, y, and z coordinate of the ithinstrument, respectively, and wi x, wi y, and wi zrepresent the weight given to the ithinstrument in the x, y, and z directions, respectively. The weight of an instrument can be invariant to the direction or coordinate system axis. In this case, wi x= wi y= wi zsuch that the weight of the ithinstrument can simply be given as wt. Further, whenreduces to EQ. 1.

[0102] The weight of a given instrument in determining a weighted centroid of one or more instruments can depend on: a type of the given instrument; a pose of the giveninstrument; the relative pose of the given instrument to other instruments; a proximity of the given instrument to a patient or patient anatomy (e.g., the relative “depth” of the instrument); a proximity of the given instrument to a limit on its range of motion; a state of the given instrument (e.g., active, energized, etc.); a state of a procedure conducted with the computer- assisted system; and other factors not listed. Similarly, in instances where the virtual point 602 is determined with use of one or more offsets (e.g., first offset 606, second offset 608), the values of the offsets may depend on a type or types of instruments supported by the repositionable assembly, a state of a procedure conducted with the computer-assisted system, etc.

[0103] It is noted that while FIGs. 6A-6C and 7A-7C use a two-dimensional view and depict the use of two instruments, embodiments of the instant disclosure are not limited to use in two-dimensional spaces or with only two instruments. In general, the virtual point 602 is determined in a three-dimensional space comprised by the workspace. Further, embodiments disclosed herein are readily applicable to scenarios where the repositionable assembly supports one instrument, two instruments, or three or more instruments.

[0104] As discussed, embodiments disclosed herein relate to determining a virtual point within a workspace, determining a first motion to move a first instrument supported by the repositionable assembly and determining the movement of the virtual point during the first motion, and determining a second motion based on the movement of the virtual point where execution of the second motion repositions the distal portion of the proximal repositionable structure of a repositionable assembly. The second motion, in general, reduces a distance between the insertion axis defined by the proximal repositionable structure and the virtual point. In accordance with one or more embodiments, the second motion or the repositioning of the distal portion of the proximal repositionable structure is implemented at a given velocity, vprs, where the subscript “prs” refers to the proximal repositionable structure, or, in some instances, the distal portion of the proximal repositionable structure (e.g., manipulator-supporting link). In one or more embodiments, the velocity, vprs, of the proximal repositionable structure to minimize is given asVprs f CVid)^>EQ. 3 where e is the distance between the virtual point and a specified axis (e.g., insertion axis), vidis the velocity of an input device associated with the movement of one or more instruments associated with the virtual point according to the placement procedure, (■) is a function, and is a gain factor (or unit conversion factor). For example, the input device can be part of theuser input system configured to teleoperationally control and operate the repositionable assembly. For example, the input device and an instrument supported by the repositionable assembly can be coupled in a leader-follower configuration (also often called teleoperation configuration or master-slave configuration in industry) where manipulation of the input device by the user can command or cause movement of the coupled instrument.

[0105] In some embodiments, the function (■) is the identity function such that f(.vid) =vid- Insome embodiments, the function (■) simply returns a constant such as the value 1 (i.e., the function (■) has no effect on the output of EQ. 1). In some embodiments, the function f(-) is a threshold function such as f= 7J 70otherwise is a magnitude of the input device velocity and t is a velocitythreshold. In other embodiments, the function (■) non-linear. In some embodiments still, the function / (■) is dependent on, or otherwise parameterized by other factors or variables such as the distance e, a state of a procedure enacted with the computer-assisted system, etc. In some embodiments, is not constant and is dependent on one or more parameters such as the placement procedure, a mode of the computer-assisted system, the distance e, and a distance of the distal portions of the instruments from the remote center (z.e., an insertion depth, whether the procedure is “shallow,” etc.).

[0106] In general, the gain factor X configures the strength of coupling between the first motion and the second motion, or the “responsiveness” of the second motion in view of the first motion. For example, relatively large gain factors result in a second motion occurring substantially concurrently with the first motion. That is, the distal portion of the proximal repositionable structure is repositioned relatively quickly in response to a movement of the virtual point (and a non-zero distance, e, between the virtual point and the specified axis), where the virtual point is moved due to a first motion of an associated instrument. In contrast, relatively small gain factors may result in a slow second motion or sluggish response of the distal portion of the proximal repositionable structure. In one or more embodiments, another “first motion” can be determined and implemented (or, at least initiated) before completion of an initial “second motion.” In such cases, the “second motion” (or new pose of the repositionable assembly to reposition the distal portion of the proximal repositionable structure) is updated based on the updated distance, e, between the virtual point and the specified axis. In one or more embodiments, another “first motion” can be determined before completion of an original first motion. In these cases, the another firstmotion can be added (e.g., vector addition) to the original first motion such that the original first motion and the another first motion are performed together. Thus, the second motion can be determined based on the summation of first motions. In general, multiple (e.g., two, three, or more) “first motions” can be summed or otherwise aggregated to determine the second motion. Further, the first motion can be considered to occur over a first period and the second motion over a second period. A latter segment of the first period can overlap with an initial segment of the second period such that the first motion and the second motion at least partially overlap. In other words, at least a portion of the first and second motions can occur simultaneously. In one or more embodiments, determination of the second motion is performed by monitoring the movement of the virtual point during the first motion.

[0107] In one or more embodiments, the steps of determining a virtual point within a workspace, determining a first motion to move a first instrument supported by the repositionable assembly and monitoring the movement of the virtual point during the first motion, and determining a second motion based on the monitored movement of the virtual point where execution of the second motion repositions (and / or reorients) the distal portion proximal repositionable structure of a repositionable assembly, are performed continuously (e.g., in a loop) and in real-time. The aforementioned steps may be implemented using a computing system of the computer-assisted system.

[0108] As discussed, embodiments disclosed herein relate to systems and methods for repositioning a distal portion of a proximal repositionable structure (i.e., a second motion) of a repositionable assembly of a computer-assisted system in response to a monitored movement of a virtual point in a workspace, the virtual point determined based on at least one instrument supported by the repositionable assembly. Determination of the virtual point can make use of one or more predefined parameters and relationships (e.g. EQ. 1, EQ. 2) (e.g., A1(A2, weights (w1;w2, . . . , ww), etc.). Similarly, determination of the velocity of the proximal repositionable structure, vprs, can make use of one or more predefined parameters (e.g., ) and relationships (e.g., EQ. 3), where these relationships may also make use of or be parameterized by one or more parameters. The above-listed parameters can be collectively considered as a set of configurable parameters.

[0109] In one or more embodiments, one or more of the configurable parameters and relationships (e.g., A1(A2, wt, , / (■)) depend on one or more of a type of instrument s) controlled by the computer-assisted system; a pose of one or more instruments; a proximity of instrument s) to a range of motion limit; a state of instrument(s) (e.g., active, energized,etc.) a and a state e.g., current state) of a procedure or process performed with the computer- assisted system. One or more of the listed elements on which one or more of the configurable parameters and relationships depend (e.g., type of instrument, state of procedure, proximity to a range of motion limit, etc.) can be referenced as situation data. That is, in one or more embodiments situation data is acquired, the situation data indicative of one or more of: a type of instrument; a state of a procedure; a pose of one or more instruments; a proximity of one or more instruments to a patient or patient anatomy (e.g., whether a procedure is “shallow,” etc.),- a proximity of instrum ent(s) to a range of motion limit; and a state of instrum ent(s) e.g., active, energized, etc.). For example, in the context of a computer-assisted system as a medical system, various medical instruments can be attached to and manipulated by the repositionable assembly. Examples of such medical instruments can include, but are not limited to, clip appliers, needle drivers, suction and / or irrigation tools, graspers, scissors, staplers, endoscopes, and energy-emitting devices e.g., electrocautery or ablation instruments). As such, for example, first offset Axand the second offset A2can be dependent on the type of instrument(s) operated with the computer-assisted system. As another example, the value of the parameter may depend on a type of procedure conducted with the computer-assisted system, where a smaller value for may be beneficial for situations where an imaging instrument may explore the workspace without frequent adjustment of other instruments. As yet another example, an input device velocity threshold, t, can depend on the state of an instrument (e.g., energized).

[0110] In some embodiments the identification of instrument types, determination of range of motion limit proximity, etc., and the resulting tuning of one or more configurable parameters (e.g., A1(A2, , t, etc.) is performed continuously (e.g., in a loop) to enable dynamic or live adjustments as needed or desirable.

[0111] Turning to FIG. 8, a flowchart in accordance with one or more embodiments is shown. The flowchart of FIG. 8 depicts a method 800 for computer-assisted systems. The method 800 may be used to reconfigure (i.e., alter a pose) a supporting structure of a computer-assisted system. One or more of the steps in FIG. 8 may be performed by various components of systems, previously described with reference to FIGs. 1, 2A, 2B, 3, 4A, 4B, and 5A-5D. While these figures illustrate particular configurations of computer assisted systems, the method is equally applicable to other configurations. The method may be executed on one or more processors, e.g., of the control system of the computer-assisted system.

[0112] While the various steps in the flowchart are presented and described sequentially, one of ordinary skill will appreciate that some or all of the steps may be executed in different orders, may be combined or omitted, and some or all of the steps may be executed in parallel. Additional steps may further be performed. Furthermore, the steps may be performed actively or passively. For example, some steps may be performed using polling or be interrupt driven in accordance with one or more embodiments of the invention.

[0113] The subsequently described steps may be performed for repositionable assemblies as previously described or any other repositionable assemblies. In some embodiments, the repositionable assembly supports multiple instruments (e.g., two, three, or more instruments), each having multiple links. In some examples, a repositionable assembly may comprise a proximal repositionable structure and one or more distal repositionable structures. The one or more distal repositionable structures may each support or couple to one or more instruments. Examples of repositionable assemblies and instruments disposed on the repositionable assemblies include but are not limited to those previously discussed in reference to FIGS. 1, 2A, 2B, 3, 4A, and 4B. A reachable space of one or more instruments supported by the repositionable assembly may be affected, e.g., moved, by movement of a distal portion of the proximal repositionable structure comprised by a reconfiguration of the repositionable assembly. The subsequently described steps may be used to determine a virtual point in a workspace and reconfigure the repositionable assembly based on the virtual point.

[0114] As stated, the method 800 may be used to reconfigure a supporting structure of a computer-assisted system. In one or more embodiments, the computer-assisted system includes a repositionable assembly. The repositionable assembly is configured to support and move at least one instrument. The repositionable assembly can be used to perform a procedure or operation in a workspace. The repositionable assembly can include a proximal repositionable structure configured to support one or more distal repositionable structures. A distal repositionable structure, in turn, can support one or more instruments. In some implementations, an instrument is directly supported by the proximal repositionable structure without an intermediary distal repositionable structure. The proximal repositionable structure can define an insertion axis.

[0115] Turning to the method 800, in Step 802, a virtual point within the workspace of the repositionable assembly is determined. The virtual point is determined according to a placement procedure. In general, a placement procedure considers the pose of at least one instrument supported by the repositionable assembly such that determination of the virtualpoint may be said to be based on the pose of at least one instrument. For example, in some implementations, the virtual point is determined relative to a first instrument that is an imaging instrument (i.e., including an imaging device). The spatial relationship between the position and orientation of the first instrument and the virtual point can include one or more offsets. That is, the virtual point may be offset from the first instrument. In other implementations, the virtual point is determined using the positions of two or more instruments. For example, the virtual point may be determined to reside at a centroid of the two or more instruments. The placement procedure defines the procedure for determining the virtual point. The placement procedure may be selected by an operator of the computer- assisted system or may be selected, or known, based on situation data related to the use and operation of the computer-assisted system. The situation data can include, for example, an indication of a type of procedure performed, or to be performed, using the computer-assisted system, a state of a procedure enacted using the computer-assisted system, a type of one or more instruments employed by the computer-assisted system, a proximity of instruments to a patient or patient anatomy, among other things. The placement procedure can make use of one or more parameters and relationships such as one or more offset values. These parameters and relationships (i.e., configurable parameters) can similarly depend on the situation data.

[0116] In Step 804, a first motion to move a first instrument supported by the repositionable assembly is determined. Movement of the first instrument can affect the position of the virtual point. In one or more embodiments the first instrument is an imaging instrument and the first motion, when performed, adjusts a field of view of the first instrument.

[0117] In Step 806, movement of the virtual point during the first motion is determined. In one or more embodiments, the real-time position of the virtual point in the workspace of the repositionable assembly is tracked (e.g., monitored), where the position of the virtual point is subject to change with movement of the first instrument. The movement of the virtual point may induce a distance between the virtual point and a specified axis (e.g., insertion axis of the proximal repositionable structure).

[0118] In Step 808, a second motion is determined based on the monitored movement of the virtual point. The second motion includes motion, or a command, to reconfigure the repositionable assembly (e.g., to reposition the distal portion of the proximal repositionable structure). In one or more embodiments, the second motion is based on a distance between the virtual point and a specified axis (e.g., insertion axis of the proximal repositionablestructure). For example, the second motion, when executed, can be performed to reduce the distance between the virtual point and the specified axis. Determination of the second motion can include processing the position of the virtual point, or a distance between the virtual point and a specified axis, with a function. In one or more embodiments, the function indicates a velocity at which the second motion, or repositioning of the distal portion of the proximal repositionable structure, occurs. The function can accept additional inputs and / or be parameterized by one or more configurable parameters. The configurable parameters can be selected based on, or computed according to, situation data. For example, in some embodiments, the function accepts as an input the velocity of an input device configured to teleoperationally control at least a portion of the computer-assisted system (e.g, the first instrument). In one or more embodiments, the velocity at which the second motion is performed is proportional to the velocity of an input device that controls the first instrument (i.e., is responsible for the first motion). For example, manipulation of the input device by an operator of the computer-assisted system can command or induce movement of the first instrument (i.e., the first motion). Then, the second motion, or reconfiguration of the repositionable assembly (e.g, to reposition the distal portion of the proximal repositionable structure), as determined by the monitored movement of the virtual point with the first instrument, is performed at a velocity based on the velocity of the input device.

[0119] In Step 810, the second motion to reconfigure the repositionable assembly is executed. Notably, Steps 802 through 810 can be performed substantially concurrently, e.g., in a continuous loop. In some instances, the second motion need not be fully realized before determination of new “second motion” based on the monitored movement of the virtual point due to one or more “first motions.” That is, the second motion can be continually updated, e.g., in real time, based on the movement of the virtual point due to a first motion, where the first motion can be temporally long-lasting. For example, another “first motion” can be determined before completion of an original first motion. In these cases, the another first motion can be added (e.g., vector addition) to the original first motion such that the original first motion and the another first motion are performed together. Thus, the second motion can be determined based on the summation of first motions. In general, multiple (e.g., two, three, or more) “first motions” can be summed or otherwise aggregated to determine the second motion. Further, the first motion can be considered to occur over a first period and the second motion over a second period. A latter segment of the first period can overlap with an initial segment of the second period such that the first motion and the second motion at least partially overlap. In other words, at least a portion of the first and second motions canoccur simultaneously. In one or more embodiments, determination of the second motion is performed by monitoring the movement of the virtual point during the first motion.

[0120] In one or more embodiments, the method 800 is performed using a computing system of the computer-assisted system. The computing system can include a non-transitory computer-readable (or machine-readable) medium storing instructions thereon that when executed using one or more computer processors perform, or cause to be performed, the steps of the method 800.

[0121] In accordance with one or more embodiments, execution of the second motion serves to reconfigure the repositionable assembly (e.g., reposition a distal portion of a proximal repositionable structure of the repositionable assembly of the computer-assisted system) to an adjusted pose. In some implementations, e.g., depending on the use case of the computer-assisted system and / or the placement procedure, the adjusted pose of the repositionable assembly aligns the reachable space of one or more instruments supported by the repositionable assembly and a field of view. A stated benefit of this behavior, as realized according to embodiments disclosed herein, is that an operator of the computer-assisted system can reasonably expect to be able to reach, or interact with, using an instrument supported by the repositionable assembly, an item or target viewable in the field of view. In other words, and in accordance with one or more embodiments, an operator can adjust a field of view for visualizing a region of the workspace and the repositionable assembly is automatically reconfigured such that instruments supported by the repositionable assembly can access the visualized region (i.e., the region captured by the field of view), as allowed by any imposed constraints. In other implementations, the automatically adjusted pose of the repositionable assembly centers the reachable space of one or more instruments with respect to the one or more instruments, themselves.

[0122] Although only a few example embodiments have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from this invention. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims.

Claims

CLAIMSWhat is claimed is:

1. A computer-assisted system comprising: a repositionable assembly configured to support and move one or more instruments; and a control system comprising one or more processors, the control system configured to: determine a virtual point within a workspace; determine a first motion to move a first instrument supported by the repositionable assembly; determine movement of the virtual point based on the first motion; determine a second motion based on the movement of the virtual point; and execute the second motion to reconfigure the repositionable assembly.

2. The computer-assisted system of claim 1, wherein a segment of the first motion and a segment of the second motion occur simultaneously.

3. The computer-assisted system of claim 1, wherein: the control system is further configured to: determine another first motion to move the first instrument; and aggregate the first motion and the another first motion; the movement of the virtual point is based on the aggregated first motion.

4. The computer-assisted system of claim 1, the control system further configured to: obtain situation data, wherein one or more of the virtual point, first motion, and second motion are based on the situation data.

5. The computer-assisted system according to claim 4, wherein the situation data comprises one or more of: a type of the first instrument; a pose of the first instrument; a proximity of the first instrument to a patient or patient anatomy; a proximity of the first instrument to a range of motion limit; a state of the first instrument; or a state of procedure performed using the computer-assisted system.

6. The computer-assisted system of claim 1, wherein: determining the second motion comprises determining a distance between the virtual point and an axis defined by the repositionable assembly; and executing the second motion reduces the distance.

7. The computer-assisted system of claim 6, wherein: determining the second motion further comprises determining a velocity of the second motion; and the velocity of the second motion is based on the distance.

8. The computer-assisted system of claim 7, wherein the velocity of the second motion is further based on a gain factor.

9. The computer-assisted system of claim 1, further comprising an input device configured to receive user input, wherein: determining the first motion to move the first instrument is based on user input received from the input device.

10. The computer-assisted system of claim 9, wherein determining the second motion further comprises determining a velocity of the second motion and the velocity of the second motion is based on a velocity of the input device.

11. The computer-assisted system of claim 10, wherein: the control system is further configured to determine the velocity of the input device; and the velocity of the second motion is zero in response to a determination that a magnitude of the velocity of the input device is less than a velocity threshold.

12. The computer-assisted system of claim 1, wherein the virtual point is determined based on a pose of the first instrument.

13. The computer-assisted system of any of claims 1-12, wherein: the first instrument comprises an imaging device; the imaging device defines a field of view axis; and the virtual point is determined relative to the field of view axis by a first offset and a second offset.

14. The computer-assisted system of claim 13 wherein: the first instrument further comprises a distal link proximal to the imaging device; and the first offset is equal to a length of the distal link.

15. The computer-assisted system of any of claims 1-12, wherein: the repositionable assembly defines an insertion axis; and the virtual point is determined relative to the insertion axis by a first offset and a second offset.

16. The computer-assisted system of any of claims 1-12, wherein the repositionable assembly further supports a second instrument.

17. The computer-assisted system of claim 16, wherein the control system is further configured to: determine whether the second instrument is anchored, and constrain, in response to the determination that the second instrument is anchored, the second motion based on a position of the second instrument.

18. The computer-assisted system of claim 16, wherein the virtual point is further determined based on a position of the second instrument.

19. The computer-assisted system of claim 18, wherein the virtual point is coincident with a centroid of a position of first instrument and the position of the second instrument.

20. A method for controlling a computer-assisted system, the method performed by a control system of the computer-assisted system and comprising: determining a virtual point within a workspace; determining a first motion to move a first instrument supported by a repositionable assembly of the computer-assisted system; determining a movement of the virtual point based on the first motion; determining a second motion based on the movement of the virtual point; and executing the second motion to reconfigure the repositionable assembly.

21. The method of claim 20, wherein a segment of the first motion and a segment of the second motion occur simultaneously.

22. The method of claim 20, further comprising:determining another first motion to move the first instrument; and aggregating the first motion and the another first motion, wherein the movement of the virtual point is based on the aggregated first motion.

23. The method of claim 20, further comprising: obtaining situation data, wherein one or more of the virtual point, first motion, and second motion are based on the situation data.

24. The method according to claim 23, wherein the situation data comprises one or more of a type of the first instrument; a pose of the first instrument; a proximity of the first instrument to a patient or patient anatomy; a proximity of the first instrument to a range of motion limit; a state of the first instrument; or a state of procedure performed using the computer-assisted system.

25. The method of claim 20, wherein: determining the second motion comprises determining a distance between the virtual point and an axis defined by the repositionable assembly; and executing the second motion reduces the distance.

26. The method of claim 25, wherein: determining the second motion further comprises determining a velocity of the second motion; and the velocity of the second motion is based on the distance.

27. The method of claim 26, wherein the velocity of the second motion is further based on a gain factor.

28. The method of claim 20, further comprising: receiving a user input from an input device of the computer-assisted system, wherein determining the first motion to move the first instrument is based on the user input.

29. The method of claim 28, wherein determining the second motion further comprises determining a velocity of the second motion and the velocity of the second motion is based on a velocity of the input device.

30. The method of claim 29, further comprising: determining the velocity of the input device, wherein the velocity of the second motion is zero in response to a determination that a magnitude of the velocity of the input device is less than a velocity threshold.

31. The method of claim 20, wherein the virtual point is determined based on a pose of the first instrument.

32. The method of any of claims 20-31, wherein: the first instrument comprises an imaging device; the imaging device defines a field of view axis; and the virtual point is determined relative to the field of view axis by a first offset and a second offset.

33. The method of claim 32 wherein: the first instrument further comprises a distal link proximal to the imaging device; and the first offset is equal to a length of the distal link.

34. The method of any of claims 20-31, wherein: the repositionable assembly defines an insertion axis; and the virtual point is determined relative to the insertion axis by a first offset and a second offset.

35. The method of any of claims 20-31, wherein the repositionable assembly further supports a second instrument.

36. The method of claim 35, further comprising: determining whether the second instrument is anchored, and constraining, in response to the determination that the second instrument is anchored, the second motion based on a position of the second instrument.

37. The method of claim 35, wherein the virtual point is further determined based on a position of the second instrument.

38. The method of claim 37, wherein the virtual point is coincident with a centroid of a position of first instrument and the position of the second instrument.

39. A non-transitory machine-readable medium comprising a plurality of machine-readable instructions executed by one or more processors associated with a computer-assisted system, the plurality of machine-readable instructions causing the one or more processors to perform the method of any of claims 20 to 38.

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