Patent Description:
Robotic arms may be coupled to a surgical table to provide power, data, and mechanical support to the arms. The functionality of the surgical table coupled to one or more robotic arms can be limited by the volume of space occupied by the robotic arms and which are generally fixed to the table and difficult to remove. Some conventional robotic arms require a technician having specialized training to connect and disconnect the robotic arms to the table such that changing and/or servicing a robotic arm is a time-consuming and expensive task. However, even trained technicians may drop and damage a robotic arm during a coupling or de-coupling operation because they do not force a user to support the arm during coupling or de-coupling. For these and other reasons, robotic arms coupled to a surgical table are considered generally fixed to each other. For example, robotic arms coupled to a surgical table should adhere to IPX4 requirements related to ingress protection against foreign objects (e.g., liquids). Adhering to this regulatory standard further complicates the design and cost of a robotic surgical arm.

Removal and reattachment of a robotic arm may introduce misalignment between the robotic arm and surgical table. In other words, conventional coupling mechanisms between a robotic arm and a surgical table do not register and/or provide confirmation that the robotic arm is positioned at a precise set of coordinates relative to the surgical table. Furthermore, some conventional robotic arm coupling mechanisms use removable components (e.g., bolts) that may be misplaced and result in misalignment and/or failure of an arm to table coupling. Additional apparatus and methods for coupling a robotic arm to a surgical table are desirable.

<CIT> describes a robot arm coupling device. Even if the coupling surface of an arm side attachment and a tool side attachment is directed in a direction other than the horizontal direction, the tool side attachment can be automatically separated and detached from the arm side attachment. When exchanging a tool, the worker does not have to forcibly pull out and detach a tool side attachment from an arm side attachment, a tool can be exchanged automatically, and the exchange work can be performed easily in a short period of time. When the cam member <NUM> is shifted from the unlocking position to the locking position, locking balls <NUM> which slide on locking inclined tapered surfaces <NUM> a to be shifted to the outside along the radius direction are engaged with engaging inclined tapered surface <NUM> a so as to mutually couple an arm side attachment <NUM> and a tool side attachment <NUM>. When the cam member <NUM> is shifted from the locking position to the unlocking position, the engagement of the locking balls <NUM> with respect to the engaging inclined tapered surfaces <NUM> a is released, and unlocking balls <NUM> which slide on thrusting inclined tapered surfaces <NUM> b to be shifted to the outside along the radius direction slide on the separating inclined tapered surfaces <NUM> b to enable to thrust the tool side attachment <NUM> from the arm side attachment <NUM>.

<CIT> describes a device for an automatic interchange and coupling of grippers on robots or manipulating devices which includes a mounting member connectable to a robot and a gripper-holding interchanging plate which is formed with recesses receiving locking balls or pins interpositioned between the interchanging plate and an actuation cone of an axially movable piston positioned in the mounting member. The movement of the piston causes the actuation cone to push the locking balls or pins to move radially outwardly into the recesses of the interchanging plate to lock the latter with the mounting member.

<CIT> describes a tool changer including male and female flanges for respectively connecting end effectors to robot arms and the like. A male flange assembly having a tapered projection is inserted into a tapered female flange member having a rod aligned along the diameter of the tapered opening. A rotatably mounted locking stud is aligned within an opening in the male tapered projection and is machined to provide a slot having locking grooves as its lower end. The stud is rotated through a <NUM> degree angle causing the male and female flanges to be drawn together until the cooperating tapers are seated together. A spring retains the flanges in the locked position. A cooperating pin and pin receiving socket respectively provided on the male and female flanges at locations displaced from the male and female tapers are utilized to assure the proper orientation between flanges and to prevent rotation of the flanges. Spring loaded electrical terminals provided on the male connecting flange firmly engage cooperating conductive terminals fixedly mounted upon the female flange to complete an electrical path between electrical sources and load utilization devices forming part of the end effectors. Pneumatic couplings are provided by means of tapered projections arranged on the male flange and cooperating tapered openings provided on the female flange. O-rings arranged on grooves on each of the tapered projections provide air-tight seals between the coupling.

<CIT> describes a robotic tool changer which comprises first and second units, operative to be separately attached to a robot and a robotic tool, and further operative to be selectively coupled together and decoupled. The first and second units are coupled and decoupled by an electric motor. Power from the electric motor may be applied to couple and decouple the first and second units in a variety of ways.

<CIT> describes a robot quick-release assembly which has a first joint member and a robot component mounted thereon, the first joint member has a first coupler and a second joint member, a robot arm mounted thereon, has a second coupler, a clamp, and a locking collar. The first coupler can be coaxially aligned with the second coupler and pressed into the second joint member, and detachably connected to the second joint member. The first mechanical coupler is detachably connected to the second mechanical coupler for transferring power across the quick-release assembly. The robot component can receive an additional electrical connector, the additional electrical connector supplying power to the robot component. The quick-release assembly coupling assembly further exerts large forces with the application of a relatively small torque to the locking collar by applying a two stage wedge engagement and can further include a sequencing system.

<CIT> describes an inherently safe robotic tool changer, in which a master unit couples to a tool unit via a first power source, and decouples from the tool unit using a separate, second power source. The second power source is only available when an attached tool is safely disposed in a tool stand. In embodiments where the first power source is not selectively applied, such as the constant bias provided by a spring, a detent mechanism maintains the master unit in a decoupled state when the master unit is removed from the tool unit. The detent mechanism allows the master unit to couple to a different tool unit upon physically abutting the new tool unit.

<CIT> describes a robotic tool coupler, in which a rotating cam surface ring having a plurality of surfaces formed therein urges a plurality of ball members in one tool coupling unit radially to contact a coupling surface in the other tool coupling unit. Mechanical energy captured and stored upon decoupling the units is used by an actuation mechanism, upon manual initiation, to at least partially automatically couple the two units by partially rotating the rotating cam surface ring. Further manual rotation of the cam member exerts a radial force through the ball members onto the coupling surface. A component of that force is directed by the coupling surface toward the opposite tool coupling unit, locking the two units together.

<CIT> describes a tool-holder B for gripping and changing tools for an industrial robot suitable for fixing to a rotary wrist-joint (<NUM>) of a robot arm, intended to carry one tool at a time. This tool-holder B comprises an upstream part Cable to be fixed to the wrist-joint (<NUM>), a downstream part D able to be fixed to a tool (El,. ) and remaining integral with the latter at each tool change, the two parts C and D being equipped with additional means for assembly and for rapid locking as well as unlocking and with detachable connectors (<NUM>, <NUM>; <NUM>, <NUM>) for supplying the tool (El) with fluid and electricity, the upstream part C containing a jack (<NUM>, <NUM>) capable of displacing the locking and unlocking components (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), and the downstream part D can be arranged in a tool magazine with the associated tool. The one-piece nature of the tool gripped in the tool-holder B ensures ease and speed of the robot's arm movements in space, maximum robot reliability, as well as rapid and powerful locking and unlocking.

The present invention is directed to an apparatus for coupling robotic arms to a surgical table having a table top on which a patient can be disposed are described herein. In some embodiments, the apparatus may allow a robotic arm to be securely coupled to and aligned with a surgical table. Methods described herein are not explicitly recited by the wording of the claims but are considered as useful for understanding the invention.

In some embodiments, the robotic arm may be quickly released from the surgical table (e.g., quick release, bail-out) such as for an emergency situation where access to the surgical table top is necessary. The robotic arm may include a first portion of a coupler and the surgical table may include a second portion of the coupler where the first portion complements the second portion. After inserting the first portion having a post into a ball bearing holder of the second portion, a user may rotate a handle to secure the coupling between the first and second portion. In some embodiments, the coupler can include kinematic mounts configured to precisely and repeatably align the first and second portions.

The above summary does not include an exhaustive list of all aspects of the present invention. It is contemplated that the invention includes all apparatuses pointed out in the claims filed with the application. Such combinations have particular advantages not specifically recited in the above summary.

The embodiments disclosed herein are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements.

In this section we shall explain several preferred embodiments with reference to the appended drawings. Whenever the shapes, relative positions and other aspects of the parts described in the embodiments are not clearly defined, the scope of the embodiments is not limited only to the parts shown, which are meant merely for the purpose of illustration. Also, while numerous details are set forth, it is understood that some embodiments may be practiced without these details. In other instances, well-known structures and techniques have not been shown in detail so as not to obscure the understanding of this description.

Apparatus and methods for providing a coupler to attach robotic arms to a surgical table having a table top on which a patient can be disposed are described herein. These apparatus and methods can be used to securely attach and align and/or quickly detach one or more robotic arms to a surgical table in a consistent manner, thereby increasing flexibility in configuring and customizing a surgical table with one or more robotic arms. For example, the coupling mechanisms described herein can be oriented and constrained in six degrees of freedom with high mechanical stiffness in the presence of external loads (e.g., robotic arm static and inertial loads during a surgical procedure).

As shown schematically in <FIG>, a surgical table <NUM> includes a table top <NUM>, a table support <NUM> and a table base <NUM>. The table top <NUM> has an upper surface on which a patient P can be disposed during a surgical procedure, as shown schematically in <FIG>. The table top <NUM> is disposed on the support <NUM>, which can be, for example, a pedestal, at a suitable height above the floor. The support <NUM> (also referred to herein as a pedestal) may provide for movement of the table top <NUM> in a desired number of degrees of freedom, such as translation in the Z-axis (height above the floor), Y-axis (along the longitudinal axis of the table), and/or X-axis (along the lateral axis of the table), and/or rotation about the Z, Y, and/or X-axes. The table top <NUM> may also include multiple sections that are movable relative to each other along / about any suitable axes, e.g., separate sections for each of the torso, one or both legs, and/or one or both arms, and a head support section. Movement of the table top <NUM> and/or its constituent sections may be performed manually, driven by motors, controlled remotely, or through any other suitable means. The support <NUM> for the table top may be mounted to the base <NUM>, which can be fixed to the floor of the operating room, or can be movable relative to the floor, e.g., by use of wheels on the base <NUM>. In some embodiments, the height of the support <NUM> can be adjusted, which together with, for example, the motion (e.g., axial (longitudinal) or lateral motion) of the table top <NUM>, can allow for the table top <NUM> to be positioned at a desired surgical site at a certain height above the floor (e.g., to allow surgeon access) and a certain distance from the support <NUM>. This also can allow robotic arms (e.g., arms <NUM> discussed below) coupled to the table <NUM> to reach a desired treatment target on a patient P disposed on the table top <NUM>.

In a robotically-assisted surgical procedure, one or more robotic arms <NUM> (shown schematically in <FIG>) can be disposed in a desired operative position relative to a patient disposed on the table top <NUM> of the surgical table <NUM> (also referred to herein as "table"). The robotic arm(s) can be used to perform a surgical procedure on a patient disposed on the surgical table <NUM>. In particular, the distal end of each robotic arm can be disposed in a desired operative position so that a medical instrument coupled to the distal end of the robotic arm can perform a desired function.

As shown schematically in <FIG>, each robotic arm <NUM> can include a distal end portion <NUM> and a proximal end portion <NUM>. The distal end portion <NUM> (also referred to herein as "operating end") can include or have coupled thereto a medical instrument or tool <NUM>. The proximal end portion <NUM> (also referred to herein as the "mounting end portion" or "mounting end") can include the coupling portion to allow the robotic arm <NUM> to be coupled to the table <NUM>. The robotic arm <NUM> can include two or more link members or segments <NUM> coupled together at joints that can provide for translation along and/or rotation about one or more of the X, Y and/or Z-axes (shown, for example, in <FIG>). The coupling portion of the robotic arm <NUM> can include a coupling mechanism <NUM>. The coupling mechanism <NUM> can be disposed at the mounting end <NUM> of the arm <NUM> and may be coupled to a segment <NUM> or incorporated within a segment <NUM>. The robotic arm <NUM> also includes a target joint J1 disposed at or near the mounting end <NUM> of the robotic arm <NUM> that can be included within the coupling mechanism <NUM> and/or the coupling portion or can be disposed on a link or segment <NUM> of the robotic arm <NUM> that is coupled to the coupling portion. The target joint J1 can provide a pivot joint to allow a distal segment of the robotic arm <NUM> to pivot relative to the table <NUM>. The robotic arm <NUM> can be moved between various extended configurations for use during a surgical procedure, as shown in <FIG>, and various folded or collapsed configurations for storage when not in use, as shown in <FIG>.

Various embodiments illustrating and describing apparatus and methods for coupling a robotic arm to a surgical table are disclosed herein. As described above and in accordance with various embodiments disclosed in more detail below, a robotic arm for use in performing a surgical procedure may be releasably coupled to a surgical table. In some embodiments, robotic arms can be coupled at a fixed location on the table or can be coupled such that the robotic arms can be movable to multiple locations relative to the table top. For example, as shown schematically in <FIG>, robotic arms <NUM> can be coupled to a table top <NUM> of a surgical table <NUM>. The surgical table <NUM> can be the same or similar in structure and function to the surgical table <NUM> described above. For example, the table top <NUM> has an upper surface on which a patient P can be disposed during a surgical procedure. In some embodiments, the robotic arms <NUM> can be permanently or releasably coupled, in a fixed or movable location, to an arm adapter that is coupled to or separate from the surgical table. For example, as shown schematically in <FIG>, an arm adapter <NUM> can be coupled to or separate from but engageable with or couplable to the table top <NUM>. The robotic arms <NUM> can be coupled to the arm adapter <NUM>.

As shown schematically in <FIG>, a coupler <NUM> may be provided to couple a robotic arm <NUM> to a surgical table <NUM>. The coupler <NUM> as described herein is usable with any of the surgical tables and robotic arms (e.g., surgical table <NUM>, <NUM>, robotic arms <NUM>, <NUM>), and methods described herein. The coupler <NUM> can include a first portion <NUM> (e.g., arm adapter) such as a terminal base portion A for a robotic arm. The coupler <NUM> can include a second portion <NUM> such as a base portion B for mounting to the surgical table <NUM>. The robotic arm <NUM> can be coupled to the first portion <NUM> and the table top <NUM> can be coupled to the second portion <NUM> prior to coupling of the first portion <NUM> to the second portion <NUM>. The coupling of the robotic arm <NUM> to the surgical table <NUM> can allow the robotic arm coupled to the table <NUM> to reach a desired treatment target on a patient disposed on the table top <NUM>. The first portion <NUM> and the second portion <NUM> may further include electrical power and data connectors. It should be appreciated that the first portion <NUM> and second portion <NUM> may be reversed such that the first portion <NUM> couples to the table <NUM> and the second portion <NUM> couples to the robotic arm <NUM>.

A surgical table <NUM> includes a table top <NUM>, a table support <NUM> and a table base <NUM>. The table top <NUM> has an upper surface on which a patient can be disposed during a surgical procedure, as shown schematically in <FIG>. The table top <NUM> is disposed on the support <NUM>, which can be, for example, a pedestal, at a suitable height above the floor. The support <NUM> may provide for movement of the table top <NUM> in a desired number of degrees of freedom, such as translation in the Z-axis (height above the floor), Y axis (along the longitudinal axis of the table), and/or X-axis (along the lateral axis of the table), and/or rotation about the Z, Y, and/or X axes. The support <NUM> for the table top <NUM> may be mounted to the base <NUM>, which can be fixed to the floor of the operating room, or can be movable relative to the floor, e.g., by use of wheels on the base <NUM>. In a robotically-assisted surgical procedure, one or more robotic arms <NUM> (shown schematically in <FIG>) can be disposed in a desired operative position relative to a patient disposed on the table top <NUM> of the surgical table <NUM>.

<FIG> is a side view of an embodiment of a coupler <NUM> including a first portion <NUM> and a second portion <NUM>. Coupling of the first portion <NUM> and second portion <NUM> forms a secure mating connection where six degrees of freedom are constrained. For example, the secure mating connection y-axisconstrains a translation in the Z-axis, a Y axis, and/or X-axis, and/or rotation about the Z, Y, and/or X-axes, of the first portion <NUM> with respect to the second portion <NUM>. The first portion <NUM> includes a handle <NUM> configured to lock and secure the coupling between the first portion <NUM> and second portion <NUM>, and a set of V-grooves <NUM> configured to contact a corresponding kinematic mount <NUM>, as described herein. The second portion <NUM> includes a post <NUM> (e.g., locking post) that may be translated along a Y axis to mate with the first portion <NUM>. Coupling the post <NUM> to the first portion <NUM> may constrain translation along the Y axis. <FIG> illustrates the X-axis, Y axis, and Z-axis relative to the coupler <NUM>.

The second portion <NUM> may further include a set of kinematic mounts <NUM> that may include at least three kinematic mounts that protrude from a surface of the second portion <NUM> and are configured to slide into and mate with a corresponding V-groove <NUM>. The kinematic mounts <NUM> and V-grooves <NUM> are configured to locate, constrain, and support the coupling between the first portion <NUM> and second portion <NUM>. The kinematic mounts <NUM> may include a spherical or semi-spherical shape. The kinematic mounts <NUM> may be equally spaced apart around the post <NUM> of the second portion <NUM>. The V-grooves <NUM> may form a V-shaped cut-out in the first portion <NUM> and may further include a groove at a vertex of the "V". The sphere-in-groove mating connection between the kinematic mounts <NUM> and V-grooves <NUM> may constrain translation in the X-axis and Z-axis and constrain rotation about the X-axis, Y axis, and Z-axis.

Some embodiments of the second portion <NUM> may include one or more alignment protrusions <NUM> configured to contact and slide into and mate with a corresponding hole (not shown) in the first portion <NUM>. The alignment protrusion <NUM> is asymmetrical in that alignment of the protrusion <NUM> with the first portion <NUM> is configured to prevent a user from inserting the first portion <NUM> incorrectly into the second portion <NUM>. This process may be referred to herein as registration. The shape of the alignment protrusion <NUM> shown is having a semispherical end, but is not particularly limited. The post <NUM> of the second portion <NUM> will not be translated along the Y axis sufficiently into the first portion <NUM> to engage coupling and locking of the first portion <NUM> to the second portion <NUM> when the alignment protrusion <NUM> is misaligned. For example, <FIG> illustrates the second portion <NUM> partially inserted into the first portion <NUM>. The alignment protrusion <NUM> and alignment hole <NUM> are oriented so as to permit the post <NUM> of the second portion <NUM> to be fully translated into the first portion <NUM>. Otherwise, the alignment protrusion <NUM> contacts the housing of the first portion <NUM> to create a gap between the first portion <NUM> and the second portion <NUM> that prevents their coupling.

<FIG> illustrates a perspective view of the first portion <NUM> aligned and having an initial engagement with the second portion <NUM>. The handle <NUM> (e.g., lock handle) is in a first position corresponding to a first position (e.g., unlocked position) of the coupler <NUM>. A user may rotate the handle <NUM> into a second position (e.g., locked position) to transition the coupler <NUM> from a first configuration (e.g., unlocked state or position) to a second configuration (e.g., locked state or position). <FIG> illustrates an alignment state of the first configuration where the post <NUM> is translated into first portion <NUM>, and the first portion <NUM> and second portion <NUM> are aligned, but without engaging a locking mechanism between the first portion <NUM> and the second portion <NUM>. In particular, each of the kinematic mounts <NUM> are aligned with and engaged to contact and mate with a corresponding V-groove <NUM>.

<FIG> is a cross-sectional side view of the initial translation of the second portion <NUM> into the first portion <NUM>. From this view, it can be seen that first portion <NUM> includes a first end <NUM> (the end that attaches to the robotic arm) and a second end <NUM> (the end that attaches to second portion <NUM>), and an interior cavity <NUM> formed within first portion <NUM>, between the first and second ends. An opening to the interior cavity is formed through the second end <NUM>. The first portion <NUM> further includes a ball bearing holder <NUM> (e.g., draw bar) coupled to a set of ball bearings <NUM>, which are positioned within interior cavity <NUM>. The set of ball bearings <NUM> may include four or more ball bearings equally spaced apart along a circumference of the ball bearing holder <NUM>. The handle <NUM> may be coupled to a pair of cams including a first face cam <NUM> and a second face cam <NUM>. A set of Belleville washers <NUM> may be coupled a shaft of the ball bearing holder <NUM>. The post <NUM> of the second portion <NUM> may include a first surface <NUM> (e.g., lead in taper) configured to permit misalignment during translation and sliding of the post <NUM> into the ball bearing holder <NUM>. The post may further include a second surface <NUM> (e.g., angled face) configured to press against the ball bearings <NUM> when the mating connection is locked. The first surface <NUM> and second surface <NUM> experience Hertzian stresses based on the curvature of the surfaces. The curvature and material properties, along with the ball bearing <NUM> diameter and material may be configured to generate contact conditions that do not deteriorate the surfaces.

The ball bearing holder <NUM> is configured to hold the ball bearings <NUM> and surround the post <NUM>. The ball bearing holder <NUM> is configured to translate along the Y axis relative to a housing of the first portion <NUM> when the face cams are rotated by the handle <NUM>. The translation of the ball bearing holder <NUM> into the first portion <NUM> presses the ball bearings <NUM> into surfaces in the first portion <NUM>, surfaces in the ball bearing holder <NUM>, and surfaces in the post <NUM>. As illustrated herein, the ball bearing holder <NUM> may include a lip on each ball bearing pocket configured to retain the ball bearing <NUM> within the holder <NUM> when the ball bearings <NUM> are not in contact with the post <NUM>. These surfaces experience Hertzian stresses based on the curvature of the surfaces. The curvature and material properties, along with the ball bearing <NUM> diameter and material may be configured to generate contact conditions that do not deteriorate the surfaces. The ball bearings <NUM> move within a predetermined range within the ball bearing holder <NUM> and serve as a locking mechanism to apply forces to both the first portion <NUM> and second portion <NUM> to securely lock them together and form a coupling between the first portion <NUM> and the second portion <NUM>.

<FIG> is a cross-sectional perspective view of the coupler <NUM> in a locked state (or locked position) illustrating the first face cam <NUM> and second face cam <NUM> in a maximally separated position where the ball bearing holder <NUM> is maximally translated into the first portion <NUM> and the ball bearings <NUM> have engaged the post <NUM> and housing <NUM> to securely lock and couple the first portion <NUM> to the second portion <NUM> (e.g., the locked position). The first face cam <NUM> and second face cam <NUM> are coupled to the ball bearing holder <NUM> such that translation of the face cams along the Y-axis also translates the ball bearing holder <NUM> along the Y-axis. Each of the face cams may include a profile that converts rotational motion (e.g., from motion of handle <NUM>) about the Y-axis into translational motion about the Y-axis. The handle <NUM> may be threaded directly into one of the face cams, thereby allowing for a torque advantage when the face cams are rotated into the locked position. The face cams may include a variable cam profile having a first and second profile. A first profile may be configured to permit relatively greater translation and a relatively lower axial force advantage. A second profile may be configured to permit a relatively lower translation and a relatively greater axial force advantage. For example, the first profile may be steep and a second profile may be shallow. In some embodiments, the varying cam profile may configured to permit a large translation (e.g., <NUM>") followed by a very small (e.g., <NUM>") translation. In some embodiments, the face cams may include a compound profile that decreases the pitch as the ball bearing holder reaches full engagement (e.g., as the ball bearing holder translates towards a lock position. In some embodiments, the face cams may include a thrust bearing to reduce friction on the outer surfaces of the face cam. In some embodiments, the face cams may include lobes configured to distribute pressure evenly. In some embodiments, different portions of the face cams may be made of different materials in order to variably change friction and/or strength of the face cams.

<FIG> are cross-sectional side views of the coupler <NUM> in various states (e.g., unlocked and locked). <FIG> illustrates an initial engagement state where surfaces of the post <NUM> are in contact with the ball bearing <NUM> within the ball bearing holder <NUM>. The handle <NUM> (not shown) and the face cams <NUM>, <NUM> are in an unlocked position. <FIG> illustrates a locked position of the coupler <NUM> after rotation of the handle <NUM> (not shown) to a locked position. The rotation of the handle <NUM> is converted into translational motion of the face cams <NUM>, <NUM> along the Y-axis such that the first face cam <NUM> and the second face cam <NUM> are maximally separated. The ball bearing holder <NUM> coupled to the face cams <NUM>, <NUM> is thereby translated along the Y-axis to bring the ball bearings <NUM> and second portion <NUM> further into the first portion <NUM>. The contact between the ball bearings <NUM> and the surfaces of the first portion <NUM> and the second portion <NUM> securely engage and lock the first portion <NUM> to the second portion <NUM>. <FIG> is a detailed view of the locking mechanism of the coupler <NUM>. The ball bearing holder <NUM> in a locked position translates the ball bearings <NUM> into the first portion <NUM> to make contact with a contact surface <NUM> of the first portion <NUM>, a ball bearing lip <NUM> of the ball bearing holder <NUM>, and a second surface <NUM> of the post <NUM>. These contact forces are sufficient to constrain the translation of the first portion <NUM> and the second portion along the Y-axis until the handle <NUM> is rotated to an unlocked position. In other words, the coupler <NUM> is self-locking in that the coupling will not become disengaged without user input.

<FIG> illustrates a set of Belleville washers <NUM> coupled to a threaded shaft of the ball bearing holder <NUM>. The Belleville washers <NUM> may be configured to apply a holding force to ball bearing holder <NUM>. In some embodiments, the Belleville washers may apply between about <NUM> force and about <NUM> force. <FIG> illustrates a spring <NUM> (e.g., compression spring) coupled between an end of the housing of the first portion <NUM> and the Belleville washers <NUM>. The spring <NUM> may be configured to provide the spring force to reset the position of the ball bearing holder <NUM> and hold the handle <NUM> in the unlocked position. The spring <NUM> may be configured to bias the ball bearing holder <NUM> into an unlocked position such that when a user rotates the handle <NUM> to an unlocked position, the ball bearing holder <NUM> will translate along the Y-axis towards an initial position such as shown in <FIG>. The Belleville washers <NUM> may be configured to vary a force of the lock.

<FIG> is a flowchart of a method <NUM> of coupling a robotic arm to a surgical table, such as by using any of the couplers described herein. The method <NUM> includes translating at <NUM> a second portion (e.g., robotic arm base portion) of a coupler into a first portion of the coupler (e.g., mounting portion of a surgical table top) (<FIG>). A post of the second portion may begin to align at <NUM> as the post moves into the first portion (<FIG>). The locking mechanism of the first portion (e.g., ball bearing holder, ball bearings, face cams, handle) will not engage if the alignment element(s) of the second portion are not aligned with the first portion. When the post is in an initial engagement state with the ball bearing holder (<FIG>), the handle may be rotated at <NUM> to rotate the two face cams. In some embodiments, the lock may rotate about <NUM> degrees from an unlocked position to a locked position. As the lock travels through its arc, the face cams move apart and translate the ball bearing holder further into the first portion (<FIG>). The ball bearing holder engages the set of ball bearings so as to press the ball bearings against surfaces of the first portion and the second portion (<FIG>). The pressing force locks at <NUM> the first and second portions together. As the ball bearing holder is translated into the first portion in response to handle rotation into the locked position, a set of kinematic mounts engage with corresponding V - grooves to precisely align the first and second portions (<FIG>). In order to decouple the coupler <NUM>, a user may rotate the handle at <NUM> towards the unlocked position. This rotates the face cams towards each other and translates the ball bearing holder towards the second portion, thereby releasing the force between the ball bearings and the housing of the first portion. With the lock disengaged, the second portion may be fully decoupled from the first portion by translating the second portion out of the first portion at <NUM>.

<FIG> are perspective views of an embodiment of a coupler <NUM> driven by a motor and having a manual coupling mechanism that may be used to couple and decouple in cases where power is lost and/or emergency operation. The coupler <NUM> may include a first portion <NUM> and a second portion <NUM>. Coupling of the first portion <NUM> and the second portion <NUM> forms a secure mating connection where six degrees of freedom are constrained. The second portion <NUM> may include a post <NUM> configured to surround the first portion <NUM>. The post <NUM> may be translated along a Y-axis to mate with the first portion <NUM> to constrain the translation along the Y-axis.

The first portion <NUM> may include a set of ball bearings <NUM>, a cam <NUM> coupled to a bushing <NUM>, and a shaft <NUM>. The set of ball bearings <NUM> may include four or more ball bearings equally spaced apart along a circumference of the first portion <NUM>. The set of ball bearings <NUM> may be moved by a locking mechanism configured to securely engage and lock the first portion <NUM> to the second portion <NUM>. The cam <NUM> is configured to translate along the Y-axis relative to a housing of the first portion <NUM> when driven by a motor and/or handle <NUM>. The post <NUM> and the cam <NUM> experience Hertzian stresses based on the curvature of those surfaces. The curvature and material properties, along with the ball bearing <NUM> diameter and material may be configured to generate contact conditions that do not deteriorate those surfaces. Movement of a cam <NUM> into a locked position will position the set of ball bearings <NUM> in holding contact force between surfaces of the post <NUM> of the second portion and surfaces of the cam <NUM>. The cam <NUM> and the bushing <NUM> may be configured to be slidable along the shaft <NUM>. Movement of the cam <NUM> along the shaft <NUM> may vary a contact force of the set of ball bearings <NUM> against a contact surface of the post <NUM> when the first portion <NUM> and the second portion <NUM> are translated into each other. A contact surface of the post <NUM> may include a post lip <NUM> configured to retain the ball bearings <NUM> within the second portion <NUM>. The ball bearings <NUM> move within a predetermined range first portion <NUM> and serve as a locking mechanism to apply forces to both the first portion <NUM> and second portion <NUM> to securely lock them together and form a coupling between the first portion <NUM> and the second portion <NUM>.

The cam <NUM> may be driven by a worm gear including a worm wheel <NUM> and worm <NUM>) using a motor <NUM> to couple and decouple the first portion <NUM> and the second portion <NUM>. The motor <NUM> may be, for example, a brushless DC motor. The first portion <NUM> may include a handle <NUM> configured to permit a user to actuate in order to slide the cam <NUM> along the shaft <NUM> and engage or release the set of ball bearings <NUM> from contact with a contact surface of the post <NUM>. The handle <NUM> may rotate between a locked position and an unlocked position and transition the coupler <NUM> between a locked configuration and an unlocked configuration. <FIG> illustrates a locked position of the coupler <NUM>. In the locked position, the contact between the ball bearings <NUM> and the post <NUM> of the second portion <NUM> and the cam <NUM> securely engage and lock the first portion <NUM> to the second portion <NUM>.

Rotation of the handle <NUM> towards the unlocked position is converted into translational motion of the cam <NUM> along the Y-axis to disengage contact between the ball bearings <NUM> and surfaces of the post <NUM> and the cam <NUM>. A spring <NUM> may be coupled between the bushing <NUM> and the worm wheel <NUM> and configured to provide the spring force to reset the position of the cam <NUM> into an unlocked position where the cam <NUM> is biased towards the worm gear.

As shown in <FIG>, the post <NUM> may include one or more relief cuts <NUM> that may be configured to provide a desired level of holding force between the first portion <NUM> and the second portion <NUM>. For example, a wider and/or longer gap in the relief cuts <NUM> may reduce the maximum holding force between the first portion <NUM> and the second portion <NUM>. The second portion <NUM> may further include a post lip <NUM>. In some embodiments, the coupler <NUM> may include kinematic mounts, V-grooves, and/or alignment elements as described herein.

In some embodiments, a rotational collet may be used to couple and decouple a first and second portion of a coupler. <FIG> is a cross-sectional perspective view of an embodiment of a coupler <NUM>. The coupler <NUM> includes a first portion <NUM> having an outer housing <NUM> and a first portion threading <NUM>. The coupler <NUM> also includes a second portion <NUM> having a post <NUM>. That may be translated along a Y-axis to mate with the first portion <NUM> to constrain translation along the Y-axis. Coupling of the first portion <NUM> and the second portion <NUM> forms a secure mating connection where six degrees of freedom are constrained. The first potion <NUM> may include a collet <NUM> configured to lock and secure the coupling between the first portion <NUM> and the second portion <NUM>. The first portion <NUM> includes a ball bearing holder <NUM> configured to receive, engage, and lock with the post <NUM>. The ball bearing holder <NUM> is configured to hold the ball bearings <NUM> and surround the post <NUM>. The ball bearing holder <NUM> is configured to translate along the Y-axis relative to a housing of the first portion <NUM> when the collet <NUM> is rotated. The translation of the ball bearing holder <NUM> into the first portion <NUM> presses the ball bearings <NUM> into the first portion <NUM>, the ball bearing holder <NUM>, and the post <NUM>. As illustrated herein, the ball bearing holder <NUM> may include a lip on each ball bearing pocket configured to retain the ball bearing <NUM> within the holder <NUM> when the ball bearings <NUM> are not in contact with the post <NUM>. These surfaces experience Hertzian stresses based on the curvature of the surfaces. The curvature and material properties, along with the ball bearing <NUM> diameter and material may be configured to generate contact conditions that do not deteriorate the surfaces. The ball bearings <NUM> move within a predetermined range within the ball bearing holder <NUM> and serve as a locking mechanism to apply forces to both the first portion <NUM> and second portion <NUM> to securely lock them together and form a coupling between the first portion <NUM> and the second portion <NUM>.

A set of Belleville washers <NUM>, a lock collar <NUM>, and a thrust bearing <NUM> may be coupled to the ball bearing holder <NUM>. The collet <NUM> may be configured to rotate about the first portion <NUM> so as to lock and unlock the post <NUM> from the ball bearing holder <NUM>. An outer surface of the collet <NUM> may be a locking knob that the user can rotate to couple and decouple the first portion <NUM> and second portion <NUM>.

<FIG> are cross-sectional side views of the coupler <NUM> in different coupling states. In the decoupled state shown in <FIG>, the set of Belleville washers <NUM> are compressed and the knob portion (of the collet <NUM>) is turned in. The second portion <NUM> is being translated into the first portion <NUM> but has not made contact with the ball bearing holder <NUM>. In <FIG>, the first portion <NUM> and second portion <NUM> have made an initial engagement where the post <NUM> contacts the ball bearing holder <NUM>. The collet <NUM> is in a first position corresponding to an unlocked position of the coupler <NUM>. The set of Belleville washers <NUM> are fully compressed and the knob portion of the collet <NUM> is turned in. In <FIG>, the collet knob is rotated so as to be turned out so as to draw the ball bearing holder <NUM> into the first portion <NUM> and lock the post <NUM> to the first portion <NUM>. The set of Belleville washers <NUM> are at a work load compression. Both the post <NUM> and the first portion <NUM> are held by a holding force using a set of ball bearings <NUM>. The set of ball bearings <NUM> may include four or more ball bearings equally spaced apart along a circumference of ball bearing holder <NUM>. In some embodiments, the coupler <NUM> may include kinematic mounts, V-grooves, and/or alignment elements as describe herein.

<FIG> is a cross-sectional side view of an embodiment of a coupler <NUM> driven by a motorized locking mechanism that may generate high forces to ensure the coupling is constrained and maintained in six degrees of freedom even in the presence of external loads (e.g., robotic arm static and inertial loads during a surgical procedure). The coupler <NUM> may include a first portion <NUM> and a second portion <NUM>. Coupling of the first portion <NUM> and second portion <NUM> forms a secure mating connection where six degrees of freedom are constrained. From this view, it can be seen that first portion <NUM> includes a first end <NUM> (the end coupled to the robotic arm) and a second end <NUM> (the end coupled to second portion <NUM>), and an interior cavity <NUM> formed within first portion <NUM>, between the first and second ends. An opening to the interior cavity <NUM> is formed through the second end <NUM>. The first portion <NUM> may include a locking mechanism coupled to a drive mechanism configured to lock and secure the coupling between the first portion <NUM> and the second portion <NUM>. The second portion includes a post <NUM> that may be translated along a Y-axis to mate with the first portion <NUM> to constrain translation along the Y-axis. The post <NUM> includes a lead screw <NUM> that may be coupled to a corresponding threaded portion <NUM> of a rotatable collet <NUM>. A motor <NUM> may drive the collet <NUM> to rotate about the lead screw <NUM> in a first direction so as to translate the lead screw <NUM> into the first portion <NUM> along the Y-axis. In this manner, the collet <NUM> may be engaged with the post <NUM> to securely lock and couple the first portion <NUM> to the second portion <NUM>. Rotation of the collet <NUM> in a second direction opposite the first direction may translate the lead screw <NUM> out of the first portion <NUM> along the Y-axis. In some embodiments, the pitch angle of the lead screw <NUM> may be between about <NUM> degrees and about <NUM> degrees. In some embodiments, the pitch angle of the lead screw <NUM> may be between about <NUM> degrees and about <NUM> degrees. In some embodiments, the pitch angle of the lead screw <NUM> may be configured to prevent the lead screw <NUM> from being backdriven.

The motor <NUM> may be coupled to a gearbox <NUM> and configured to rotate the collet <NUM>. The collet <NUM> may be coupled to one or more bearings <NUM>. The bearings <NUM> may be, for example, a deep groove ball bearing. The gearbox <NUM> may be, for example, a planetary or harmonic gear box and may have a gear ratio of about <NUM> to about <NUM>. The motor <NUM> may be, for example, a brushless DC motor. In some embodiments, the motorized locking mechanism may generate a force of at least <NUM> N. In some embodiments, the motorized locking mechanism may generate a force of at least <NUM> N.

The motor <NUM> may be coupled to a controller (not shown) configured to receive input commands from a user. For example, a robotic arm may include a switch that may input a coupling command to lock and unlock the first portion <NUM> from the second portion <NUM> by driving the lead screw in either direction, thereby attaching and detaching the robotic arm from a surgical table. The switch may be provided on a surgical table, medical cart, and/or portable computing device.

In some embodiments, the coupler <NUM> may include a connection sensor <NUM> configured to detect coupling and decoupling between the first portion <NUM> and the second portion <NUM>. In some embodiments, the connection sensor may include one or more of a force sensor, Hall effect sensor, and electrical switch located on either the first portion <NUM> and the second portion <NUM> (e.g., at an interface between the first portion <NUM> and the second portion <NUM>). In some embodiments, the connection sensor may include an encoder on the motor <NUM>. A controller may be configured to drive the collet <NUM> using the motor <NUM> until a coupling or decoupling has been detected.

In some embodiments, the coupler <NUM> may include kinematic mounts, V-grooves, and/or alignment elements as described herein. The motorized locking mechanism of coupler <NUM> may reduce user error in coupling the first portion <NUM> to the second portion <NUM> including partial coupling and decoupling, usability risk (e.g., non-intuitive use), and increase safety (e.g., robotic arm falling to the floor on onto a user's foot or leg).

<FIG> is a perspective side view of an embodiment of a coupler <NUM>. The coupler <NUM> can include a first portion <NUM> such as a base portion for mounting to a surgical table (e.g., surgical table <NUM>). The coupler <NUM> can include a second portion <NUM> (e.g., arm adapter) such as a terminal base portion for a robotic arm. Coupling of the first portion <NUM> and second portion <NUM> forms a secure mating connection where six degrees of freedom are constrained. The first portion <NUM> includes a handle <NUM> configured to lock and secure the coupling between the first portion <NUM> and second portion <NUM>, and an alignment protrusion <NUM> configured to contact a corresponding alignment hole (not shown), as described herein. The first portion <NUM> includes a cone <NUM> that may be translated along a Y-axis to mate with a conical receiving hole <NUM> (<FIG>) of the second portion <NUM> to constrain translation along the Y-axis. <FIG> illustrates the X-axis, Y-axis, and Z-axis relative to the coupler <NUM>. It should be appreciated that the first portion <NUM> and second portion <NUM> may be reversed such that the first portion <NUM> couples to a surgical table and the second portion <NUM> couples to a robotic arm.

The first portion <NUM> may include one or more alignment protrusions <NUM> configured to contact and slide into and mate with a corresponding alignment hole <NUM> in the second portion <NUM>. The alignment protrusion <NUM> is asymmetrical in that alignment of the protrusion <NUM> with the second portion <NUM> is configured to prevent a user from inserting the first portion <NUM> incorrectly into the second portion <NUM>. This process may be referred to herein as registration. The shape of the alignment protrusion <NUM> is shown having a cylindrical shape, but is not particularly limited. For example, the alignment protrusion <NUM> may include a spring loaded/split pin. When the alignment protrusion <NUM> is misaligned with the alignment hole <NUM>, the cone <NUM> of the first portion <NUM> will not be translated along the Y-axis sufficiently into the conical hole <NUM> of the second portion <NUM> to engage coupling and locking of the first portion <NUM> to the second portion <NUM>. For example, <FIG> illustrates the alignment protrusion <NUM> of the first portion <NUM> aligned with the alignment hole <NUM> of the second portion <NUM> so as to permit the cone <NUM> to be fully translated into the second portion <NUM>. Otherwise, the alignment protrusion <NUM> contacts the housing of the second portion <NUM> to create a gap between the first portion <NUM> and the second portion <NUM> that prevents their coupling.

The cone <NUM> is configured to provide a large surface area to form a mechanical coupling having rigidity. For example, the cone <NUM> is configured to couple the first portion <NUM> and second portion <NUM> so as to constrain translation in the X-axis and Y-axis, and constrain rotation about the X-axis and Z-axis. The surface of the cone <NUM> forms mating surfaces that may have tight tolerances and a surface finish ensuring proper contact with the second portion <NUM>. In some embodiments, the contact surface may include a surface roughness configured to increase friction between the first portion <NUM> and the second portion <NUM>. A taper angle of the cone <NUM> may be configured for low release forces while maintaining high rigidity of the coupling. In some embodiments, the cone <NUM> may have a taper angle of about <NUM> degrees.

In some embodiments, the cone <NUM> may include edges or planes that contact the alternating mating surface. In some embodiments, a pin <NUM> may be disposed at a nose of the cone <NUM> and may be configured to protrude from and recess into a surface of the cone <NUM>. When the handle <NUM> is rotated to an unlock position, the pin may be configured to protrude from the cone <NUM> to aid in the release and translation of the second portion <NUM> away from the first portion <NUM> by pushing the first portion <NUM> and second portion <NUM> away from each other in the event that they remain in contact due to friction.

<FIG> illustrates a side view of the first portion <NUM> and second portion <NUM>. The cone <NUM> may include two or more catches <NUM> configured to constrain translation of the second portion <NUM> along the Y-axis. For example, the catches <NUM> may be disposed along opposite lateral sides of the conical taper of the cone <NUM>. The catches <NUM> may be configured as an initial locking mechanism (e.g., spring catch) to prevent a robotic arm attached to the second portion <NUM> from falling out and away from the cone <NUM> of the first portion <NUM>. The catch <NUM> may include an angled, flat surface configured to slide easily over a surface of a conical hole <NUM>. The catch <NUM> may include a tapered portion configured to hold the first portion <NUM> against the second portion <NUM>. The second portion <NUM> includes a switch <NUM> having a corresponding catch <NUM> configured to move the catches <NUM> from a first configuration to a second configuration. The catches <NUM> may be biased to protrude from the cone <NUM> in the first configuration and be recessed into the cone <NUM> in the second configuration. <FIG> shows the second portion <NUM> being translated over the cone <NUM>. When the second portion <NUM> is translated over the cone <NUM>, the catches <NUM> make contact with the surface of the conical hole <NUM> and are recessed into the cone <NUM>. The catches <NUM> advanced over corresponding axial grooves <NUM> (<FIG>) allows the catches <NUM> to protrude out in the first configuration to thereby couple and secure the first portion <NUM> to the second portion <NUM> in an initial lock state, as shown in <FIG>. <FIG> is a perspective view of the first portion <NUM> and second portion <NUM> in the initial lock state. The handle <NUM> is in an unlocked state throughout the steps shown in <FIG>.

<FIG> and <FIG> shows a first surface <NUM> and a second surface <NUM> of the catch <NUM>. The first surface <NUM> may be an angled, flat surface having an angled similar to that of the taper angle of the cone <NUM>. The first surface <NUM> may be configured to permit the catch <NUM> to slide easily over a surface of a conical hole <NUM>. As the first surface <NUM> translates through the conical hole <NUM> of the second portion <NUM>, the catch <NUM> is recessed into the cone <NUM>. The second surface <NUM> may a tapered portion configured to hold the first portion <NUM> against the second portion <NUM>. The second surface <NUM> of the catch <NUM> may include an anti-release angle <NUM> configured to prevent the catch <NUM> from decoupling from the second portion <NUM> when the catch <NUM> is in a protruding configuration. The catches <NUM> may be configured to be biased towards the protruding configuration.

In some embodiments, the catches <NUM> may include a camming surface configured to contact a corresponding surf ace such that by wedging the catches outward rather than being pulled back, the first portion <NUM> and second portion <NUM> may be secured and locked together. For example, the camming surface may include an angle surface, a ball and socket surface, and/or the like.

<FIG> illustrates a set of Belleville washers <NUM> coupled to the catches <NUM> and shuttle <NUM>. The Belleville washers <NUM> may be configured to apply a holding force to the catch <NUM>. In some embodiments, the Belleville washers <NUM> may apply between about <NUM> force and about <NUM> force. The Belleville washers <NUM> may be configured to vary a force of the lock (e.g., handle <NUM>, cam <NUM>, and shuttle <NUM>). In some embodiments, a precompression force of the Belleville washers <NUM> may be adjusted using an auxiliary input.

The handle <NUM> coupled to the cam <NUM> is illustrated in <FIG> and <FIG>. The cam <NUM> is configured to rotate in response to rotation of the handle <NUM> between unlocked and locked positions. Rotation of the cam <NUM> towards a locked position applies contact forces to the shuttle <NUM> disposed within the cone <NUM>. As the handle <NUM> rotates through its arc, the cam <NUM> applies force against the shuttle <NUM> of the first portion <NUM> to bring the first portion <NUM> and second portion <NUM> together and securely lock the first portion <NUM> to the second portion <NUM> with high rigidity. When the handle <NUM> is in the locked position, the first portion <NUM> and second portion <NUM> are securely engaged and locked to each other. In some embodiments, the first portion may include a motorized locking mechanism as described herein, in place of the handle <NUM> and cam <NUM>. In some embodiments, the cam <NUM> may be rotated indirectly through, for example, a set of right angle gears or rotational motion about an axis separate from the cam <NUM> axis.

To release the second portion <NUM> from the initial lock state (where the handle <NUM> is in the unlocked position), the switch <NUM> may be actuated by being pressed in, thereby pressing in the catches <NUM> in a second configuration and allowing a user to translate the second portion <NUM> away from the first portion <NUM>. <FIG>-<FIG> illustrates front, side, top, and perspective views, respectively, of the switches <NUM>. A switch <NUM> may include a release point <NUM> configured to make contact with and push a corresponding axial switch <NUM> into the recessed second configuration. The switch <NUM> may rotate about a hinge <NUM> when actuated. In some embodiments, the switches <NUM> may be spaced apart by about <NUM>. This allows a user to engage both switches <NUM> simultaneously using one hand wrapped around second portion <NUM>, thereby naturally encouraging the placement of the user's hand in a position to support the arm (and reduce the likelihood of a dropped arm) when the second portion <NUM> is decoupled form the first portion <NUM>. Each switch <NUM> may include a torsion spring configured to bias the switch <NUM> to an initial, reset position.

In some embodiments, the first portion <NUM> and the second portion <NUM> may each include an electrical interface <NUM> to provide a power and/or data connection between the first portion <NUM> and the second portion <NUM>. The electrical interface may include one or more of a spring contact pin, wiping contacts, a fiber optic interface, transformers, or any other power and/or data connector. In some embodiments, the electrical interface of the first portion <NUM> may be disposed on the tapered surface of the cone <NUM> or on the base flange of the first portion <NUM> that supports the cone <NUM>. In some embodiments, one or more of the catches <NUM> may include an electrical interface since the catches <NUM> contact the second portion <NUM>.

In some embodiments, the coupler <NUM> may include one or more connection sensors <NUM>, as described herein, and configured to detect coupling and decoupling between the first portion <NUM> and the second portion <NUM>. For example, connection sensors may be configured to detect one or more of an amount of force the catches <NUM> are holding, a location of the catches <NUM> (e.g., amount that the catches have moved), and a contact state between the cone <NUM> and the second portion <NUM>.

In some embodiments, one or more of the first portion <NUM> and second portion <NUM> may include a dampener configured to vibrationally isolate the first portion <NUM> from the second portion <NUM>.

<FIG> is a flowchart of a method <NUM> of coupling a robotic arm to a surgical table, such as by using any of the couplers described herein. The method <NUM> includes translating at <NUM> a second portion (e.g., robotic arm base portion) of a coupler over a first portion of the coupler (e.g., mounting portion of a surgical table top) (<FIG>). A conical taper of the first portion may provide initial alignment. The second portion at <NUM> is further aligned with the first portion as the second portion is translated over a cone of the first portion by aligning corresponding alignment elements on each of the first and second portions. The locking mechanism of the first portion (e.g., catches) will not engage with the second portion if the alignment element(s) of the first portion are not aligned with the second portion. The catches are engaged with the second portion at <NUM> (<FIG>). This initial coupling of the catches to the second portion is self-locking in that the coupling will not become disengaged (e.g., released) without user input (e.g., user actuation of a switch). At this point, the first portion and second portion are coupled in an initial engagement state such that the second portion is unable to fall away from the first portion if the second portion was unsupported by a user.

While in the initial engagement state, a handle may be rotated at <NUM> to rotate a two position cam of the first portion to apply contact forces to a shuttle disposed within the cone. As the handle rotates through its arc, the cam applies force against the shuttle of the first portion to bring the first portion and second portion together and securely lock the first portion to the second portion with high rigidity. In some embodiments, the handle may rotate about <NUM> degrees from an unlocked position to a locked position. The first portion and second portion are locked at <NUM>.

To disengage the first portion from the second portion, the handle must be rotated to an unlock position before a catch switch is actuated. Accidental decoupling is reduced by required both locks to be decoupled by a user. The handle may be rotated at <NUM> towards an unlocked position to rotate the cam and decouple it from the shuttle. Rotation of the handle to the unlocked position does not fully decouple the first portion and second portion, and permits the user to support the mass of a robotic arm coupled to the second portion. Actuation of one or more switches at <NUM> recesses the catches into the cone and allows the second portion to translate at <NUM> out and away from the cone of the first portion.

<FIG>, <FIG>, and <FIG> are cross-sectional side views of embodiments of a coupler <NUM> including a first portion <NUM> and a second portion <NUM>. Coupling of the first portion <NUM> and second portion <NUM> forms a secure mating connection where six degrees of freedom are constrained. The first and second portion may each include an electrical interface <NUM> to provide power and data through the coupler <NUM>. The first portion <NUM> includes a ball bearing <NUM> coupled to a spring <NUM> configured to couple the first portion <NUM> to the second portion <NUM>. In some embodiments, a positive lock may be further coupled to spring <NUM> to prevent spring back. The second portion <NUM> includes a post <NUM> that may be translated along a Y-axis to mate with the first portion <NUM>. The second portion <NUM> may include a first surface <NUM> and a second surface <NUM>. The second surface <NUM> may have a steeper angle relative to the first surface <NUM>. A radial clamp <NUM> may be disposed around the second portion <NUM>. Coupling of the post <NUM> to the first portion <NUM> may constrain translation along the Y-axis.

<FIG> illustrates the first portion <NUM> aligned and having an initial engagement with the second portion <NUM>. The post <NUM> of the second portion <NUM> may include the first surface <NUM> (e.g., lead in taper) configured to permit misalignment during translation and sliding of the post <NUM> into the first portion <NUM>. The post <NUM> may further include a second surface <NUM> (e.g., angled face) configured to press against the ball bearings <NUM>. The first surface <NUM> and second surface <NUM> experience Hertzian stresses based on the curvature of the surfaces. The curvature and material properties, along with the ball bearing <NUM> diameter and material may be configured to generate contact conditions that do not deteriorate the surfaces.

The clamp <NUM> may be tightened to lock the first portion <NUM> to the second portion <NUM>. <FIG> are front cross-sectional view of the radial clamp <NUM> coupled to an actuator <NUM>. The actuator <NUM> may include a screw <NUM> and handle <NUM>. A user actuating the handle <NUM> may turn the screw <NUM> to vary a radial compression force of the clamp <NUM> on the second portion <NUM>. The actuator <NUM> may be pivoted or rotated. In some embodiments, the actuator <NUM> may be rotated a quarter turn to achieve a desired radial compression of clamp <NUM>. The clamp <NUM> may also include one or more reliefs <NUM> to distribute compression forces. The clamp compresses within a predetermined range and serve as a locking mechanism to apply forces to both the first portion <NUM> and second portion <NUM> to securely lock them together and form a coupling between the first portion <NUM> and the second portion <NUM>.

<FIG> illustrates a coupler <NUM> including a first collet <NUM> and a second collet <NUM>. The first collet <NUM> may be configured to couple to an end of the second portion <NUM> between the first portion <NUM> and the second portion <NUM>. The second collet <NUM> may be configured to couple to a base portion of the second portion <NUM> between the first portion <NUM> and the second portion <NUM>. The first collet <NUM> and second collet <NUM> are both coupled to a toggle <NUM> having a handle <NUM> for a user to translate along a Y-axis. The outer and inner surfaces of the collets may match an angle of respective first and second portions such that the collets may translate and compress between the first and second portions. In some embodiments, the collets may be coupled to a set of Belleville washers to provide a predetermined compression force. The first collet <NUM> and second collet <NUM> may each include one or more slits <NUM>, <NUM> (see <FIG>) such that translation of the toggle <NUM> towards the first portion <NUM> will compress the collets and secure the coupling between the first and second portions. The collets translate and compress within a predetermined range and serve as a locking mechanism to apply forces to both the first portion <NUM> and second portion <NUM> to securely lock them together and form a coupling between the first portion <NUM> and the second portion <NUM>. In some embodiments, compression of the collets at a predetermined force forms an electrical interface connection.

<FIG> illustrates a coupler <NUM> including a first clamp <NUM> and a second clamp <NUM>. The first clamp <NUM> may be configured to couple to and vary a radial compression force to an end of the second portion <NUM>. The second clamp <NUM> may be configured to couple and vary a radial compression force. In some embodiments, the first clamp <NUM> and second clamp <NUM> may be coupled to a respective first cam <NUM> and second cam <NUM>, as shown in <FIG>. Each of the cams may be coupled to a handle and actuated together to vary a radial compression force on the second portion <NUM>. The first cam <NUM> and second cam <NUM> may have different profiles and may be actuated using rotary or linear motion. In addition, cams <NUM>, <NUM> may allow for different timing, different compression and/or linear motion and clamping of the clamps <NUM>, <NUM>. Each of the clamps compresses within a predetermined range and serve as a locking mechanism to apply forces to both the first portion <NUM> and second portion <NUM> to securely lock them together and form a coupling between the first portion <NUM> and the second portion <NUM>. In some embodiments, compression of the radial clamp at a predetermined force forms an electrical interface connection.

<FIG> is a flowchart of a method <NUM> of coupling a robotic arm to a surgical table, such as by using any of the couplers described herein. The method <NUM> includes translating at <NUM> a second portion (e.g., robotic arm base portion) of a coupler into a first portion of the coupler (e.g., mounting portion of a surgical table top). A post of the second portion may begin to align at <NUM> as the post moves into the first portion. The locking mechanism of the first portion (e.g., radial clamp, handle, actuator, knob) will not engage if the alignment element(s) of the second portion are not aligned with the first portion. When the post is in an initial engagement state against a set of ball bearings, the handle may be rotated at <NUM> to compress the radial clamp. The pressing force of the radial clamp locks at <NUM> the first and second portions together. In order to decouple the coupler <NUM>, a user may rotate the handle at <NUM> towards the unlocked position. This decompresses the radial clamp, thereby releasing the force between the ball bearings and the housing of the second portion. With the lock disengaged, the second portion may be fully decoupled from the first portion by translating the second portion out of the first portion at <NUM>.

<FIG> are perspective views of embodiments of a coupler <NUM> including a first portion <NUM> and a second portion <NUM>. Coupling of the first portion <NUM> and second portion <NUM> forms a secure mating connection where six degrees of freedom are constrained. The first and second portion may each include an electrical interface to provide power and data through the coupler <NUM>. The post hole <NUM> may include a first electrical connector <NUM> shown in <FIG> configured to couple to a second electrical connector <NUM> shown in <FIG>.

The second portion <NUM> includes a post <NUM> that may be translated along a Y-axis to mate with the first portion <NUM>. The post <NUM> may include a set of catches <NUM> biased to protrude from the post <NUM> in the first configuration and be recessed into the post <NUM> in the second configuration. The first portion <NUM> includes a post hole <NUM> and a set of catch holes <NUM> corresponding to the set of catches <NUM> of the second portion <NUM>. The catches <NUM> may be driven by a lead screw <NUM> coupled to a motor <NUM>. As the lead screw <NUM> is translated along a Y-axis, a linear rack <NUM> coupled to the lead screw <NUM> translates along a Y-axis and rotates a catch <NUM> between the first and second configurations. This motorized locking mechanism may ensure a secure coupling between the first portion <NUM> and second portion <NUM>. The second portion <NUM> may include an access port <NUM> (see <FIG>) for a user to manually insert a tool (e.g., Allen wrench) to manually backdrive the linear rack <NUM> and enable decoupling of the robotic arm from the surgical table. The motor <NUM> may be, for example, a brushless DC motor.

<FIG> are exterior views of a linear rack assembly <NUM> including a linear rack <NUM> and catch <NUM>. The linear rack <NUM> may be dual sided in that the rack <NUM> of one side (see <FIG>) is interchangeable with that of the other side. In other words, the rack <NUM> of <FIG> may be flipped and mated to be symmetric. The linear rack <NUM> may include one or more Belleville washers to increase compliance for the catches <NUM> (e.g., rotating cam claws). A post may be provided at one end of each rack to allow each rack to press together. A washer <NUM> may be disposed between the mating surfaces of the racks <NUM> to add compliance and spring resistance. The catch <NUM> may include a spur gear <NUM> and a cam claw <NUM> separated in height by an offset <NUM> as illustrated by <FIG>. The catch <NUM> may rotate about an axis <NUM>. The cam claw <NUM> may mate with a corresponding surface of the first portion as the catch rotates.

<FIG> are internal perspective views of a coupler <NUM>, according to an embodiment. In some embodiments, the coupler <NUM> may include a set of three catches biased to protrude from the surface of a housing in the first configuration and be recessed into the housing in the second configuration. The catches <NUM>, <NUM>, <NUM> may be driven by a lead screw <NUM> coupled to a motor <NUM>. As the lead screw <NUM> is translated along a Y-axis, a linear rack <NUM> coupled to the lead screw <NUM> translates along a Y-axis and rotates the catch <NUM>, <NUM>, <NUM> between the first and second configurations. The coupler <NUM> may include an access port <NUM> for a user to manually insert a tool (e.g., Allen wrench) to manually backdrive the linear rack <NUM> and enable decoupling of the robotic arm from the surgical table. The motor <NUM> may be, for example, a brushless DC motor.

<FIG> is an internal and external view of a coupler <NUM> including a motorized locking mechanism. A first portion <NUM> may include a motor <NUM> coupled to a ball bearing <NUM> configured to apply a holding force against a release member <NUM> of a second portion <NUM>. The motor <NUM> applies a downward force within a predetermined range and serves as a vibration damper and locking mechanism to apply forces to both the first portion <NUM> and second portion <NUM> to securely lock them together and form a coupling between the first portion <NUM> and the second portion <NUM>. The release member <NUM> includes a bearing surface <NUM> configured to contact the ball bearing <NUM>. The bearing surface <NUM> includes a tapered or ramped surface to allow the bearing <NUM> to recess into the release member <NUM>. The release member <NUM> may rotate about a hinge <NUM>. A pin <NUM> may secure the release member <NUM>. However, when the pin <NUM> is released, the force of gravity and the downward pressure of the bearing <NUM> will cause the release member <NUM> to swing open so as to release the contact force between the first portion <NUM> and second portion <NUM>, thereby decoupling the first portion <NUM> and the second portion <NUM>.

<FIG> are schematic side views of a coupler <NUM> including a translation mechanism. A first portion <NUM> may include a carriage including a set of latches <NUM> to secure a post <NUM> of a second portion <NUM>. To couple the first portion <NUM> and second portion <NUM>, the post <NUM> is translated into the first portion <NUM>. To decouple the first portion <NUM> and second portion <NUM>, the post is further translated into the first portion <NUM> for a predetermined distance, and then may be retracted to decouple the first portion <NUM> and second portion <NUM>.

In <FIG>, a distal head <NUM> is translated into the first portion <NUM> to contact an angled first surface <NUM> of the latches <NUM>. The latches may be coupled to springs <NUM> biased to extend toward the other latch. The distal head <NUM> slides through the latches such that the latches <NUM> contact a second diameter portion <NUM> of the post <NUM>. At this point, the post <NUM> is prevented from retracting from the first portion <NUM> by the contact between the latch <NUM> and proximal end of the distal head <NUM>. The post <NUM> includes a sliding collar <NUM> that may slide along the second diameter portion <NUM> of the post <NUM>.

In <FIG>, the post <NUM> is further translated into the first portion <NUM> such that the latch <NUM> slides along the second diameter portion <NUM>. The first surface <NUM> of the latch <NUM> is configured to slide against the first surface <NUM> of the sliding collar <NUM> such that the latches <NUM> hold the sliding collar <NUM> in place. At this point, retraction of the post <NUM> away from the first portion <NUM> will translate the distal head <NUM> in a reverse direction while the sliding collar remains fixed with respect to the latches <NUM>. In other words, the sliding collar <NUM> will slide along the second diameter portion <NUM> from a proximal end to a distal end. When the sliding collar <NUM> contacts the distal head <NUM>, the opening of the latches <NUM> is of a diameter such that distal head <NUM> is not prevented from retracting away from the first portion <NUM>. In some embodiments, the distal head <NUM> at a proximal end may include a recess to hold the sliding collar <NUM>.

<FIG> are side views of a grasper <NUM> configured to surround and grasp a post of a coupler of any of the previous embodiments. The grasper <NUM> includes arms <NUM>, <NUM> operable to apply a lateral force to a longitudinal axis of the post (e.g., post <NUM>) of the coupler (e.g., coupler <NUM>).

While various embodiments have been described above, it should be understood that they have been presented by way of example only, and not limitation. Where methods described above indicate certain events occurring in certain order, the ordering of certain events may be modified. Additionally, certain of the events may be performed concurrently in a parallel process when possible, as well as performed sequentially as described above.

Where schematics and/or embodiments described above indicate certain components arranged in certain orientations or positions, the arrangement of components may be modified. While the embodiments have been particularly shown and described, it will be understood that various changes in form and details may be made. Any portion of the apparatus and/or methods described herein may be combined in any combination, except mutually exclusive combinations. The embodiments described herein can include various combinations and/or sub-combinations of the functions, components and/or features of the different embodiments described.

Claim 1:
A coupler (<NUM>) for coupling a robotic arm to a surgical table, the coupler (<NUM>) comprising:
a first portion (<NUM>) configured to couple to a robotic arm;
a second portion (<NUM>) configured to couple to a surgical table, the second portion (<NUM>) having a post (<NUM>) configured to translate along a first axis of the first portion (<NUM>) to couple the second portion (<NUM>) to the first portion (<NUM>); and
a locking mechanism configured to transition a coupling between the first portion (<NUM>) and the second portion (<NUM>) between a locked position and an unlocked position, wherein in the locked position, movement of the first portion (<NUM>) relative to the second portion (<NUM>) in six degrees of freedom is constrained; and
wherein the locking mechanism comprises a first cam (<NUM>), a second cam (<NUM>) and a ball bearing assembly (<NUM>, <NUM>) positioned within an interior cavity (<NUM>) of the first portion (<NUM>),
wherein the ball bearing assembly comprises a ball bearing holder (<NUM>) and a ball bearing (<NUM>), the ball bearing holder (<NUM>) comprising a receiving cavity which receives the post (<NUM>);
wherein the first cam <NUM> and second cam <NUM> are coupled to the ball bearing holder (<NUM>),
wherein rotation of the first and second cams (<NUM>, <NUM>) causes a translation of the first and second cams (<NUM>, <NUM>) along the first axis, so as to translate the ball bearing holder (<NUM>) along the first axis, thereby translating the post (<NUM>) along the first axis to the locked position or the unlocked position;
wherein the interior cavity (<NUM>) comprises an interior contact surface and the post (<NUM>) comprises an exterior contact surface, and the ball bearing (<NUM>) contacts the interior contact surface and the exterior contact surface in the locked position.