Patent Description:
Physical guides are often used to constrain surgical tools when drilling holes or placing screws. In some cases, physical guides constrain such surgical tools for the purpose of preparing joints to accept replacement implants. The time required to position and secure a physical guide to the patient can represent a significant portion of the overall time required to perform a surgical procedure.

Navigation systems (also referred to as tracking systems) can be used to properly align and secure jigs, as well as track a position and/or orientation of a surgical tool used to drill holes. Tracking systems typically employ one or more trackers associated with the tool and the tissue being drilled. A display can then be viewed by a user to determine a current position of the tool relative to a desired trajectory. The display may be arranged in a manner that requires the user to look away from the surgical site to visualize the tool's progress. This can distract the user from focusing on the surgical site. Also, it may be difficult for the user to place the tool in a desired manner.

Robotically assisted surgery typically relies on large robots with robotic arms that can move in six degrees of freedom (DOF). These large robots may be cumbersome to operate and maneuver in the operating room.

There is a need for systems and methods to address one or more of these challenges.

<CIT> discloses a method for verifying the positional accuracy of a tracking reference device that includes a tracking reference device attached to a bone. The bone is then registered with respect to a coordinate frame of the tracking reference device. A verification mark on the bone is then created where the position of the verification mark is recorded, by way of a tracking system, with respect to the tracking reference device. The positional accuracy of the tracking reference device is verified by instructing an end-effector of a robotic-assisted surgical device to align with the verification mark on the bone, and wherein if the end-effector does not align with the verification mark, the positional accuracy of the tracking reference device is compromised. A surgical system for performing the computerized method is also provided.

<CIT> discloses a method and system to align a pin or drill a tunnel along a single line in space with a two degree of freedom (<NUM>-DOF) surgical device in a patient. A plane is defined relative to a desired location for an implant or tunnel on a bone, where the implant or tunnel has an axis. An end-effector of the <NUM>-DOF surgical device is aligned coincident with the plane, and the <NUM>-DOF surgical device is moved side-to until a first indicator signals when the end-effector aligns with an entry point for the desired location for the implant or tunnel on the bone. A tip of the end-effector is anchored into the bone at the entry point; and the <NUM>-DOF surgical device is rotated about the anchored tip until a second indicator signals when the end-effector aligns with the axis of the implant or tunnel at the desired location.

<CIT> discloses a handheld robot for orthopedic surgery and a control method thereof. The handheld robot includes a main body, a grip, a kinematic mechanism, a tool connector, a tool, a force sensor and a positioning unit. The handheld robot combines the position/orientation information of the tool acquired by the positioning unit with the force/torque information acquired by the force sensor, and utilizes the combined information to adjust the position of the tool so as to keep the tool within the range/path of a predetermined operation plan.

The invention is defined by claims <NUM>, <NUM> and <NUM>.

One general aspect includes a hand-holdable body adapted to be freely holdable and moved by a hand of a user; and a trajectory assembly operatively connected with the hand-holdable body, the trajectory assembly including: a shaft extending from the hand-holdable body; a pivot frame coupled with the shaft. The trajectory assembly includes a guide member pivotally connected with the pivot frame; a support member outwardly extending from and connected with the guide member; two actuators coextending and substantially parallel to an axis of the shaft, each actuator pivotally connected with the support member. The trajectory assembly configured to convert linear movement of the actuators into pivotal movement of the guide member to adjust a trajectory axis, the actuators selectively configured to push and pull the support member connected with the guide member. The guide member is adjustable to a target trajectory with the actuators, adjusting the trajectory axis of the guide member in at least two degrees of freedom to align the trajectory axis with the target trajectory.

Implementations may include one or more of the following features. The guide member is configured to allow a surgical device to pass through during a surgical procedure. The pivot frame may include a recess along an inner surface of the pivot frame, a retainer is disposed within the recess, maintaining the guide member and pivot frame connection as the actuators adjust the guide member to the target trajectory. The pivot frame and the guide member may include a retention assembly, the retention assembly including a protrusion and a complimentary pocket. The retention assembly of the pivot frame may include a protrusion extending from the inner surface of the pivot frame, and the guide member may include a groove or pocket in an outer surface of the guide member that is complimentary to the protrusion. The retention assembly may restrict rotation of the guide member relative to the pivot frame, maintaining the target trajectory during actuation of the actuators. The actuators control pitch and roll of the guide member to align the guide member with the target trajectory.

The target trajectory may be set based on a surgical plan, such as planned implant location or may be set by a user, in accordance with a virtual boundary or object.

Another general aspect includes a robotically-assisted handholdable guide instrument. The robotically - assisted handholdable guide instrument also includes a hand-holdable body adapted to be freely held and moved by a hand of a user; a positioning assembly operatively connected to the hand-holdable body, the positioning assembly including a plurality of positioning actuators pivotally connected with the hand-holdable body; and a trajectory assembly operatively connected with the plurality of actuators of the positioning assembly, the trajectory assembly including: a shaft; a pivot frame connected with the shaft; a guide member pivotally connected with the pivot frame; a support member connected with the guide member; and two trajectory actuators pivotally connected to the support member. The instrument also includes where the plurality of positioning actuators operatively connect the positioning assembly with the trajectory assembly, the plurality of positioning actuators are configured to adjust a pose of the trajectory assembly in at least two degrees of freedom. The instrument also includes where trajectory assembly adjusts the guide member to a target trajectory with the trajectory actuators, adjusting a trajectory axis of the guide member in at least two degrees of freedom to align the trajectory axis with the target trajectory. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to perform the actions of the methods.

Any of the above aspects can be combined in full or in part. Any features of the above aspects can be combined in full or in part. Any of the above implementations for any aspect can be combined with any other aspect. Any of the above implementations can be combined with any other implementation whether for the same aspect or a different aspect.

Referring to <FIG>, a surgical system <NUM> is illustrated. The surgical system <NUM> is shown performing a shoulder procedure on a patient <NUM> to resect portions of the patient <NUM> so that the patient <NUM> can receive a shoulder joint implant IM. The surgical system <NUM> may be used to perform other types of surgical procedures, including procedures that involve guiding drills, screws, pins, or other forms of treatment. As seen in <FIG>, the surgical system <NUM> is shown performing a shoulder surgery. In some examples, the surgical procedure involves knee surgery, hip surgery, spine surgery, and/or ankle surgery, and may involve removing tissue to be replaced by surgical implants, such as knee implants, hip implants, shoulder implants, spine implants, and/or ankle implants. The robotic system <NUM> and techniques disclosed herein may be used to perform other procedures, surgical or non-surgical, and may be used in industrial applications or other applications where robotic systems are utilized.

Referring to <FIG>, the surgical system <NUM> includes a robotic guide instrument <NUM>. In some examples, a user manually holds and supports the guide instrument <NUM> (as shown in <FIG>). As best shown in <FIG>, the instrument <NUM> comprises a hand-held portion <NUM> for being manually grasped and/or supported by the user.

The instrument <NUM> may be freely moved and supported by a user without the aid of a guide arm, e.g., configured to be held by a human user while guiding the placement of a pin, screw, and/or drill such that the weight of the tool is supported solely by a hand of the user during the procedure. Put another way, the instrument <NUM> may be configured to be held such that the user's hand is supporting the instrument <NUM> against the force of gravity. The instrument <NUM> may weigh <NUM> lbs. or less, <NUM> lbs. or less, 5lbs. or less, or even 3lbs. <NUM> lbs ≈ <NUM>. The instrument <NUM> may have a weight corresponding to ANSI/AAMI HE75:<NUM>. The instrument <NUM> also comprises a trajectory assembly <NUM> for guiding the trajectory of a tool, such as a driver. The method for operating the instrument <NUM> may include a user suspending the weight of the instrument <NUM> without any assistance from a passive arm or robotic arm.

Referring to <FIG>, a guide member <NUM> couples to the hand-held portion <NUM> through the trajectory assembly <NUM> to align a trajectory of a surgical tool (such as a drill, screw, pin, driver, or the like) with the anatomy in certain operations of the surgical system <NUM> described further below. The guide member <NUM> may also be referred to as an end effector. The guide member <NUM> may be configured as a conduit with an open passage disposed through the conduit. In some examples, the guide member <NUM> may be configured as a tube with a constant inner diameter. In other examples, the guide member may have a larger inner diameter at a first end of the conduit and a second smaller diameter at a second end. The opening may be of any suitable size or shape to accommodate a surgical instrument such as a drill, a screw, a pin, a needle, the like, or a combination thereof. In other examples, the guide member <NUM> may have any shape capable of allowing a surgical instrument and/or surgical retainer, such as a pin or screw, to be passed through. In other examples, the guide member <NUM> may have a shape such as a "U" or a "C". The guide member <NUM> is coupled with a pivot frame <NUM>. The pivot frame <NUM> retains the guide member <NUM> while the guide member <NUM> is adjusted, constraining the guide member <NUM> to prevent rotation about the trajectory axis. In one example, the guide member <NUM> may be removable from the trajectory assembly <NUM> and pivot frame <NUM> such that new/different guide members <NUM> can be attached when needed. The guide member <NUM> may be designed to guide the trajectory of a driver or other surgical instrument into contact with the tissue of the patient <NUM>. In some examples, the surgical instrument may be a drill, or a driver as shown in <FIG>, or other type of accessory such as a biopsy needle. In other cases, the guide member may be replaced with a surgical tool. The surgical tool may be a drill, a driver, a tap, an ultrasonic instrument, a bur, a saw, or other cutting tool. In such instances, the robotic instrument would include a drive motor for the surgical tool.

An actuator assembly <NUM> comprising one or more actuators <NUM>, <NUM>, move the trajectory assembly <NUM> in two or more degrees of freedom relative to the hand-held portion <NUM> to provide robotic motion that assists in placing a surgical tool at a desired position and/or orientation (e.g., at a desired pose relative to the shoulder and/or spine during the surgical procedure), while the user manually holds the hand-held portion <NUM>. The actuator assembly <NUM> may comprise actuators <NUM>, <NUM>, that are arranged in parallel, in series, or both. In one example seen in <FIG>, the actuators <NUM>, <NUM> are arranged in parallel. In some examples, the actuators <NUM>, <NUM>, move the trajectory assembly <NUM> in two or more degrees of freedom relative to the hand-held portion <NUM>. In some examples, the actuator assembly <NUM> is configured to move the trajectory assembly <NUM> relative to the hand-held portion <NUM> in at least two degrees of freedom, such as pitch and roll. In some examples, such as shown herein, the actuators <NUM>, <NUM>, move the trajectory assembly <NUM> and its associated trajectory assembly coordinate system TCS in only two degrees of freedom relative to the hand-held portion <NUM> and its associated base coordinate system BCS. For example, the trajectory assembly <NUM> and its trajectory assembly coordinate system TCS may: rotate about its y-axis to provide pitch motion; and rotate about its x-axis to provide roll motion. It is contemplated to translate along an axis Z coincident with a z-axis of the base coordinate system BCS to provide z-axis translation motion. The allowed motions in pitch, roll, and z-axis translation are shown by arrows in <FIG> and in the schematic illustrations of <FIG>, <FIG>, <FIG>, <FIG>, and <FIG>, respectively. In some examples, actuators may move the trajectory assembly <NUM> in four or more degrees of freedom relative to the hand-held portion <NUM>.

Referring back to <FIG>, the constrain assembly <NUM> including a shaft <NUM> and a pivot frame <NUM> may be used to constrain movement of the trajectory assembly <NUM> relative to the hand-held portion <NUM> in the remaining degrees of freedom that are not controlled by the actuator assembly. The pivot frame <NUM> may comprise any suitable shape or configuration to constrain motion as described herein. In the example shown in <FIG>, the pivot frame <NUM> operates to limit motion of the trajectory assembly coordinate system TCS by: constraining rotation about the z-axis of the base coordinate system BCS to constrain yaw motion; constraining translation in the x-axis direction of the base coordinate system BCS to constrain x-axis translation; and constraining translation in the y-axis direction of the base coordinate system BCS to constrain y-axis translation. The actuator assembly <NUM> and pivot frame <NUM>, in certain situations described further below, are controlled to effectively control the trajectory of the instrument or device inserted through the guide tube, such as a drill or a pin driver.

Referring to <FIG>, an instrument controller <NUM>, or other type of control unit, is provided to control the instrument <NUM>. The instrument controller <NUM> may comprise one or more computers, or any other suitable form of controller that directs operation of the instrument <NUM> and motion of the trajectory assembly <NUM> (and guide member <NUM>) relative to the hand-held portion <NUM>. The instrument controller <NUM> may have a central processing unit (CPU) and/or other processors, memory, and storage (not shown). The instrument controller <NUM> is loaded with software as described below. The processors could include one or more processors to control operation of the instrument <NUM>. The processors can be any type of microprocessor, multi-processor, and/or multicore processing system. The instrument controller <NUM> may additionally, or alternatively, comprise one or more microcontrollers, field programmable gate arrays, systems on a chip, discrete circuitry, and/or other suitable hardware, software, or firmware that is capable of carrying out the functions described herein. The term processor is not intended to limit any embodiment to a single processor. The instrument <NUM> may also comprise a user interface UI with one or more displays and/or input devices (e.g., triggers, push buttons, foot switches, keyboard, mouse, microphone (voice-activation), gesture control devices, touchscreens, etc.).

The instrument controller <NUM> controls operation of the guide member <NUM>. The instrument controller <NUM> controls a state (e.g., position and/or orientation) of the trajectory assembly <NUM> and the guide member <NUM> with respect to the hand-held portion <NUM>. The instrument controller <NUM> can control velocity (linear or angular), acceleration, or other derivatives of motion of the guide member relative to the hand-held portion <NUM> and/or relative to the anatomy that is caused by the actuators <NUM>, <NUM>.

As shown in <FIG>, the instrument controller <NUM> may comprise a control housing <NUM> mounted to the hand-held portion <NUM> with one or more control boards <NUM> (e.g., one or more printed circuit boards and associated electronic components) located inside the control housing <NUM>. The control boards <NUM> may comprise microcontrollers, device drivers, memory, sensors, or other electronic components for controlling the actuators <NUM>, <NUM>, (e.g., via motor controllers). The instrument controller <NUM> may also comprise an off-board control console <NUM> in data and power communication with the control boards <NUM>. The sensors S, and/ or actuators <NUM>, <NUM> described herein may feed signals to the control boards <NUM>, which transmit data signals out to the console <NUM> for processing, and the console <NUM> may feed power and/or position commands back to the control boards <NUM> in order to power and control positioning of the actuators <NUM>, <NUM>. It is contemplated that the processing may also be performed on the control board(s) of the control housing. Of course, it is contemplated that no separate control housing is necessary.

In some versions, the console <NUM> may comprise a single console for powering and controlling the actuators <NUM>, <NUM> (and/ or actuators <NUM>, <NUM>, <NUM> described further below). In some versions, the console <NUM> may comprise one console for powering and controlling the actuators <NUM>, <NUM>. One such console for powering and controlling the drive motor M may be like that described in <CIT>. Flexible circuits, also known as flex circuits, may interconnect the actuators <NUM>, <NUM> and/or other components with the instrument controller <NUM>. For example, flexible circuits FC may be provided between the actuators <NUM>, <NUM>, and the control boards <NUM>. Other forms of connections, wired or wireless, may additionally, or alternatively, be present between components.

Referring briefly back to <FIG>, the surgical system <NUM> further includes a navigation system <NUM>. One example of the navigation system <NUM> is described in <CIT>. The navigation system <NUM> tracks movement of various objects. Such objects include, for example, the instrument <NUM>, the guide member <NUM> and the anatomy, e.g., the spine and shoulder. The navigation system <NUM> tracks these objects to gather state information of each object with respect to a (navigation) localizer coordinate system LCLZ. As used herein, the state of an object includes, but is not limited to, data that defines the position and/or orientation of the tracked object (e.g., coordinate systems thereof) or equivalents/derivatives of the position and/or orientation. For example, the state may be a pose of the object, and/or may include linear velocity data, angular velocity data, and the like.

The navigation system <NUM> may include a cart assembly <NUM> that houses a navigation controller <NUM>, and/or other types of control units. A navigation user interface UI is in operative communication with the navigation controller <NUM>. The navigation user interface UI includes one or more displays <NUM>. The navigation system <NUM> is capable of displaying graphical representations of the relative states of the tracked objects to the user using the one or more displays <NUM>. The navigation user interface UI further comprises one or more input devices to input information into the navigation controller <NUM> or otherwise to select/control certain aspects of the navigation controller <NUM>. Such input devices include interactive touchscreen displays. However, the input devices may include any one or more of push buttons, foot switches, a keyboard, a mouse, a microphone (voice-activation), gesture control devices, and the like.

The navigation system <NUM> also includes a navigation localizer <NUM> coupled to the navigation controller <NUM>. In one example, the localizer <NUM> is an optical localizer and includes a camera unit <NUM>. The camera unit <NUM> has an outer casing <NUM> that houses one or more optical sensors <NUM>. The localizer <NUM> may comprise its own localizer controller <NUM> and may further comprise a video camera VC.

The navigation system <NUM> includes one or more trackers. In some examples, the trackers include a pointer tracker PT, a tool tracker <NUM>, a first patient tracker <NUM>, and a second patient tracker <NUM>. In the illustrated example of <FIG>, the tool tracker <NUM> is firmly attached to the instrument <NUM>, the first patient tracker <NUM> is firmly affixed to the humerus H the patient <NUM>, and the second patient tracker <NUM> is firmly affixed to the scapula SC of the patient <NUM>. In this example, the patient trackers <NUM>, <NUM> are firmly affixed to sections of bone. The pointer tracker PT is firmly affixed to a pointer <NUM> used for registering the anatomy to the localizer coordinate system LCLZ and/or used for other calibration and/or registration functions. It is contemplated that the patient trackers could be coupled to other locations of a patient other than components of the shoulder, such as one or more vertebra, skin, bones of the leg, hip, etc..

The tool tracker <NUM> may be affixed to any suitable component of the instrument <NUM>, and in some versions may be attached to the hand-held portion <NUM>, the trajectory assembly18, directly to the guide member <NUM>, or a combination thereof. The trackers <NUM>, <NUM>, <NUM>, PT may be fixed to their respective components in any suitable manner, such as by fasteners, clamps, or the like. For example, the trackers <NUM>, <NUM>, <NUM>, PT may be rigidly fixed, flexibly connected (optical fiber), or not physically connected at all (ultrasound), as long as there is a suitable (supplemental) way to determine the relationship (measurement) of that respective tracker to the associated object. Any one or more of the trackers <NUM>, <NUM>, <NUM>, PT may include active markers. The active markers may include light emitting diodes (LEDs). Alternatively, the trackers <NUM>, <NUM>, <NUM>, PT may have passive markers, such as reflectors, which reflect light emitted from the camera unit <NUM>. Printed markers, or other suitable markers not specifically described herein, may also be utilized.

Various coordinate systems may be employed for purposes of tracking the objects. For instance, the coordinate systems may comprise the localizer coordinate system LCLZ, the trajectory assembly coordinate system TCS, the base coordinate system BCS, coordinate systems associated with each of the trackers <NUM>, <NUM>, <NUM>, PT, one or more coordinate systems associated with the anatomy, one or more coordinate systems associated with pre-operative and/or intra-operative images (e.g., CT images, MRI images, etc.) and/or models (e.g., 2D or 3D models) of the anatomy, and a TCP (tool center point) coordinate system. Coordinates in the various coordinate systems may be transformed to other coordinate systems using transformations upon establishing relationships between the coordinate systems, e.g., via registration, calibration, geometric relationships, measuring, etc..

As shown in <FIG>, in some examples, the TCP is a predetermined reference point or origin of the TCP coordinate system defined at the distal end of the guide member <NUM>. The geometry of the guide member <NUM> may be defined relative to the TCP coordinate system and/or relative to the trajectory assembly coordinate system TCS. The guide member <NUM> may comprise one or more geometric features, e.g., perimeter, circumference, radius, diameter, width, length, height, volume, area, surface/plane, range of motion envelope (along any one or more axes), etc. defined relative to the TCP coordinate system and/or relative to the trajectory assembly coordinate system TCS and stored in the navigation system <NUM>. In some examples, the guide member <NUM> has a trajectory (e.g., for placing screws) that will be described for convenience and ease of illustration, but is not intended to limit the guide member <NUM> to any particular form. Points, other primitives, meshes, other 3D models, etc., can be used to virtually represent the guide member <NUM>. The TCP coordinate system, the trajectory assembly coordinate system TCS, and the coordinate system of the tool tracker <NUM> may be defined in various ways depending on the configuration of the guide member <NUM>. For example, the pointer <NUM> may be used with calibration divots in the trajectory assembly <NUM> and/or in the guide member <NUM> for: determining (calibrating) a pose of the trajectory assembly coordinate system TCS relative to the coordinate system of the tool tracker <NUM>; determining a pose of the TCP coordinate system relative to the coordinate system of the tool tracker <NUM>; and/or determining a pose of the TCP coordinate system relative to the trajectory assembly coordinate system TCS. Other techniques could be used to measure the pose of the TCP coordinate system directly, such as by attaching and fixing one or more additional trackers/markers directly to the guide member <NUM>. In some versions, trackers/markers may also be attached and fixed to the hand-held portion <NUM>, the trajectory assembly <NUM>, or both.

Since the trajectory assembly <NUM> is movable in multiple degrees of freedom relative to the hand-held portion <NUM> via the actuators <NUM>, <NUM>, the instrument <NUM> may employ encoders, hall-effect sensors (with analog or digital output), and/or any other position sensing method, to measure a pose of the TCP coordinate system and/or trajectory assembly coordinate system TCS relative to the base coordinate system BCS. The instrument <NUM> may use measurements from sensors that measure actuation of the actuators <NUM>, <NUM> to determine a pose of the TCP coordinate system and/or trajectory assembly coordinate system TCS relative to the base coordinate system BCS, as described further below.

The localizer <NUM> monitors the trackers <NUM>, <NUM>, <NUM>, PT (e.g., coordinate systems thereof) to determine a state of each of the trackers <NUM>, <NUM>, <NUM>, PT, which correspond respectively to the state of the object respectively attached thereto. The localizer <NUM> may perform known triangulation techniques to determine the states of the trackers <NUM>, <NUM>, <NUM>, PT, and associated objects. The localizer <NUM> provides the states of the trackers <NUM>, <NUM>, <NUM>, PT to the navigation controller <NUM>. In some examples, the navigation controller <NUM> determines and communicates the states of the trackers <NUM>, <NUM>, <NUM>, PT to the instrument controller <NUM>.

The navigation controller <NUM> may comprise one or more computers, or any other suitable form of controller. Navigation controller <NUM> has a central processing unit (CPU) and/or other processors, memory, and storage (not shown). The processors can be any type of processor, microprocessor or multi-processor system. The navigation controller <NUM> is loaded with software. The software, for example, converts the signals received from the localizer <NUM> into data representative of the position and/or orientation of the objects being tracked. The navigation controller <NUM> may additionally, or alternatively, comprise one or more microcontrollers, field programmable gate arrays, systems on a chip, discrete circuitry, and/or other suitable hardware, software, or firmware that is capable of carrying out the functions described herein. The term processor is not intended to limit any embodiment to a single processor.

Although one example of the navigation system <NUM> is shown that employs triangulation techniques to determine object states, the navigation system <NUM> may have any other suitable configuration for tracking the instrument <NUM>, guide member <NUM>, and/or the patient <NUM>. In another example, the navigation system <NUM> and/or localizer <NUM> are ultrasound-based. For example, the navigation system <NUM> may comprise an ultrasound imaging device coupled to the navigation controller <NUM>. The ultrasound imaging device images any of the aforementioned objects, e.g., the instrument <NUM>, the guide member <NUM>, and/or the patient <NUM>, and generates state signals to the navigation controller <NUM> based on the ultrasound images. The ultrasound images may be 2D, 3D, or a combination of both. The navigation controller <NUM> may process the images in near real-time to determine states of the objects. The ultrasound imaging device may have any suitable configuration and may be different than the camera unit <NUM> as shown in <FIG>.

In another example, the navigation system <NUM> and/or localizer <NUM> are radio frequency (RF)-based. For example, the navigation system <NUM> may comprise an RF transceiver coupled to the navigation controller <NUM>. The instrument <NUM>, the guide member <NUM>, and/or the patient <NUM> may comprise RF emitters or transponders attached thereto. The RF emitters or transponders may be passive or actively energized. The RF transceiver transmits an RF tracking signal and generates state signals to the navigation controller <NUM> based on RF signals received from the RF emitters. The navigation controller <NUM> may analyze the received RF signals to associate relative states thereto. The RF signals may be of any suitable frequency. The RF transceiver may be positioned at any suitable location to track the objects using RF signals effectively. Furthermore, the RF emitters or transponders may have any suitable structural configuration that may be much different than the trackers <NUM>, <NUM>, <NUM>, PT shown in <FIG>.

In yet another example, the navigation system <NUM> and/or localizer <NUM> are electromagnetically based. For example, the navigation system <NUM> may comprise an EM transceiver coupled to the navigation controller <NUM>. The instrument <NUM>, the guide member <NUM>, and/or the patient <NUM> may comprise EM components attached thereto, such as any suitable magnetic tracker, electro-magnetic tracker, inductive tracker, or the like. The trackers may be passive or actively energized. The EM transceiver generates an EM field and generates state signals to the navigation controller <NUM> based upon EM signals received from the trackers. The navigation controller <NUM> may analyze the received EM signals to associate relative states thereto. Again, such navigation system <NUM> examples may have structural configurations that are different than the navigation system <NUM> configuration shown in <FIG>.

The navigation system <NUM> may have any other suitable components or structure not specifically recited herein. Furthermore, any of the techniques, methods, and/or components described above with respect to the navigation system <NUM> shown may be implemented or provided for any of the other examples of the navigation system <NUM> described herein. For example, the navigation system <NUM> may utilize solely inertial tracking or any combination of tracking techniques, and may additionally or alternatively comprise, fiber optic-based tracking, machine-vision tracking, and the like.

Referring to <FIG>, the surgical system <NUM> includes a control system <NUM> that comprises, among other components, the instrument controller <NUM> and the navigation controller <NUM>. The control system <NUM> further includes one or more software programs and software modules. The software modules may be part of the program or programs that operate on the instrument controller <NUM>, navigation controller <NUM>, or a combination thereof, to process data to assist with control of the robotic system <NUM>. The software programs and/or modules include computer readable instructions stored in memory <NUM> on the instrument controller <NUM>, navigation controller <NUM>, or a combination thereof, to be executed by one or more processors <NUM> of the controllers <NUM>, <NUM>. The memory <NUM> may be any suitable configuration of memory, such as non-transitory memory, RAM, non-volatile memory, etc., and may be implemented locally or from a remote database. Additionally, software modules for prompting and/or communicating with the user may form part of the program or programs and may include instructions stored in memory <NUM> on the instrument controller <NUM>, navigation controller <NUM>, or a combination thereof. The user may interact with any of the input devices of the navigation user interface UI or other user interface UI to communicate with the software modules. The user interface software may run on a separate device from the instrument controller <NUM> and/or navigation controller <NUM>. The instrument <NUM> may communicate with the instrument controller <NUM> via a power/data connection. The power/data connection may provide a path for the input and output used to control the instrument <NUM> based on the position and orientation data generated by the navigation system <NUM> and transmitted to the instrument controller <NUM>.

The control system <NUM> may comprise any suitable configuration of input, output, and processing devices suitable for carrying out the functions and methods described herein. The control system <NUM> may comprise the instrument controller <NUM>, the navigation controller <NUM>, or a combination thereof, and/or may comprise only one of these controllers, or additional controllers. The controllers may communicate via a wired bus or communication network as shown in <FIG>, via wireless communication, or otherwise. The control system <NUM> may also be referred to as a controller. The control system <NUM> may comprise one or more microcontrollers, field programmable gate arrays, systems on a chip, discrete circuitry, sensors, displays, user interfaces, indicators, and/or other suitable hardware, software, or firmware that is capable of carrying out the functions described herein.

In one exemplary configuration, the instrument <NUM> is best shown in <FIG>. The instrument <NUM> includes the hand-held portion <NUM> to be held by the user, the trajectory assembly <NUM> movably coupled to the hand-held portion <NUM> to support the guide member <NUM>, the actuator assembly <NUM> with the plurality of actuators <NUM>, <NUM> operatively interconnecting the trajectory assembly <NUM> and the hand-held portion <NUM> to move the trajectory assembly <NUM> in two degrees of freedom relative to the hand-held portion <NUM>, and the constraint assembly <NUM> having the pivot frame <NUM> operatively interconnecting the trajectory assembly <NUM> and the hand-held portion <NUM>.

The hand-held portion <NUM> comprises a grip <NUM> for being grasped by the user so that the user is able to manually support the instrument <NUM>. The hand-held portion <NUM> may be configured with ergonomic features such as a grip for a hand of a user to hold, a textured or mixed material coating for preventing a user's hand from slipping when wet and/or bloody. The hand-held portion <NUM> may include a taper to accommodate users with different hand sizes and contoured to mate with the contours of a user's hand and/or fingers. The hand-held portion <NUM> also comprises a base <NUM> to which the grip <NUM> is attached by one or more fasteners, adhesive, welding, or the like. The actuators <NUM>, <NUM> may be movably coupled to the base <NUM> at the joint supports <NUM>, <NUM> via joints described further below.

As best shown in <FIG>, <FIG>, and <FIG>, the trajectory assembly <NUM>, particularly the guide member <NUM>, comprises control arms <NUM>. Each control arm <NUM> including an actuator mount <NUM>, <NUM> at which the actuators <NUM>, <NUM> are to be movably coupled to the control arms <NUM> of the guide member <NUM> via joints, as described further below. The actuator mounts <NUM>, <NUM>, may comprise brackets, or the like, suitable to mount the actuators <NUM>, <NUM> such that the trajectory assembly <NUM> is able to move in at least two degrees of freedom relative to the hand-held portion <NUM>.

The actuators <NUM>, <NUM>, in the version shown, comprise electric, linear actuators that extend between the base <NUM> and the control arms <NUM> of the guide member <NUM>. When actuated, an effective length of the actuator <NUM>, <NUM> changes to vary a distance between the guide member <NUM> and the base <NUM> of the hand-held portion <NUM> along a corresponding axis of the actuator <NUM>, <NUM>. Accordingly, the actuators <NUM>, <NUM> work in concert to change their effective lengths and move the trajectory assembly <NUM> in at least two degrees of freedom relative to the hand-held portion <NUM>. In the version shown, two actuators <NUM>, <NUM> are provided, and may be referred to as first and second actuators <NUM>, <NUM> or trajectory assembly actuators <NUM>, <NUM>. The first and second actuators <NUM>, <NUM> are adjustable in effective length along a first active axis AA1 and a second active axis AA2 (see <FIG>). The first and second actuators <NUM>, <NUM> are independently adjustable in effective length to adjust one or more of a pitch orientation, a roll orientation, or both of the guide member <NUM> relative to the hand-held portion <NUM>, as previously described. More actuators may be provided in some examples described further below. The actuators <NUM>, <NUM> may comprise rotary actuators in some examples. The actuators <NUM>, <NUM> may comprise linkages having one or more links of any suitable size or shape. The actuators <NUM>, <NUM> may have any configuration suitable to enable movement of the guide member <NUM> relative to the hand-held portion <NUM> in at least two degrees of freedom.

In this version, the actuators <NUM>, <NUM> are coupled to the base <NUM> and the control arms <NUM> of the guide member <NUM> via a plurality of active joints. The active joints include a set of first active joints <NUM> that couple the actuators <NUM>, <NUM> to the base <NUM> at the actuator mounts <NUM>, <NUM>. In one version, as shown in <FIG>, the first active joints <NUM> comprises active spherical joints <NUM>. The spherical joints <NUM> comprise a socket connector <NUM>. The first socket connector <NUM> pivotally connects the actuator mounts <NUM>, <NUM> with a spherical stud <NUM> of the actuators <NUM>, <NUM>. As a result, the actuators <NUM>, <NUM> are able to move in at least two degrees of freedom relative to the base <NUM> of the hand-held portion <NUM>. Other types of active joints are also contemplated, such as active joint blocks comprising U-joints that receive pins.

Referring to <FIG>, the active joints also comprise a set of second active joints <NUM> coupling the trajectory actuators <NUM>, <NUM> to the control arms <NUM> of the guide member <NUM>. In the version shown, the second active joints <NUM> are supported at the joint supports <NUM>, <NUM>. In one example, each of the second active joints <NUM> comprises a spherical joint <NUM> arranged to pivot relative to the control arms <NUM> of the guide member <NUM>. Each spherical joint <NUM> has a ball stud <NUM> extending from the actuators <NUM>, <NUM> to pivotally engage the socket mount <NUM> in each of the control arms <NUM> at one of the joint supports <NUM>, <NUM> allowing the respective actuators <NUM>, <NUM> to pivot within its respective joint support <NUM>, <NUM> moving the guide member <NUM> relative to the hand-held portion <NUM>.

Referring to <FIG>, each of the actuators <NUM>, <NUM> comprises a housing <NUM>. The housing <NUM> comprises a canister <NUM> and a cap <NUM> threadably connected to the canister <NUM>. The ball studs <NUM> that form part of the first active joints <NUM> are fixed to the housings <NUM> such that the housings <NUM> and ball studs <NUM> are able to move together relative to the hand-held portion <NUM> via the first active joints <NUM>.

Each of the actuators <NUM>, <NUM> also comprises a motor <NUM> disposed in each housing <NUM>. The motor <NUM> has a casing <NUM> disposed in the housing <NUM> and a motor winding assembly <NUM> disposed within the casing <NUM>. Each motor <NUM> also has a rotor <NUM> fixed to the lead screw <NUM>. The lead screw <NUM> is supported for rotation in the housing <NUM> by one or more bushings and/or bearings <NUM>. The rotor <NUM> and associated lead screw <NUM> are configured to rotate relative to the housing <NUM> upon selective energization of the motor <NUM>. The lead screws <NUM> have fine pitch and lead angles to prevent backdriving (i.e., they are self-locking). As a result, a load placed on the trajectory assembly <NUM> does not easily back drive the motor <NUM>. In some examples, the lead screws <NUM> have an <NUM>-<NUM> class <NUM> thread that results in a lead of from <NUM> to <NUM> inches/revolution. Other thread types/sizes may also be employed.

Each of the actuators <NUM>, <NUM> may be controlled by a separate motor controller. Motor controllers may be wired separately to the actuators <NUM>, <NUM>, respectively, to individually direct each actuator <NUM>, <NUM> to a given target position. In some examples, the motor controllers are proportional integral derivative (PID) controllers. In some examples, the motor controllers can be integrated with or form part of the instrument controller <NUM>. For ease of illustration, the motor controllers shall be described herein as being part of the instrument controller <NUM>.

A power source provides, for example, <NUM> VDC power signals to the motors <NUM> via the console <NUM>. The <NUM> VDC signal is applied to the motors <NUM> through the instrument controller <NUM>. The instrument controller <NUM> selectively provides the power signal to each motor <NUM> to selectively activate the motors <NUM>. This selective activation of the motors <NUM> is what positions the guide member <NUM>. The motors <NUM> may be any suitable type of motor, including brushless DC servomotors, other forms of DC motors, or the like. The power source also supplies power to the instrument controller <NUM> to energize the components internal to the instrument controller <NUM>. It should be appreciated that the power source can provide other types of power signals such as, for example, <NUM> VDC, <NUM> VDC, <NUM> VDC, etc. Alternatively, the instrument may include a battery pack.

One or more sensors S (see also <FIG>) transmit signals back to the instrument controller <NUM> so that the instrument controller <NUM> can determine a current position of the associated actuator <NUM>, <NUM> (i.e., a measured position). The levels of these signals may vary as a function of the rotational position of the associated rotor <NUM>. In one implementation, the sensor(s) S may resolve the rotational position of the rotor <NUM> within a given turn at a high resolution. These sensors S may be Hall-effect sensors that output analog and/or digital signals based on the sensed magnetic fields from the rotor <NUM>, or from other magnets placed on the lead screw <NUM> (see, e.g., the <NUM>-pole magnet MG in <FIG>). A low voltage signal, e.g., <NUM> VDC, for energizing the Hall-effect sensors may be supplied from the motor controller associated with the motor <NUM> with which the Hall-effect sensors are associated. In some examples, two Hall-effect sensors are disposed in the housing <NUM> and spaced <NUM> degrees apart from each other around the rotor <NUM> to sense rotor position so that the instrument controller <NUM> is able to determine the position and count incremental turns of the rotor <NUM> (one such sensor S and magnets MG are shown in <FIG>). In some versions, the Hall-effect sensors output digital signals representing incremental counts. Various types of motors and sensor arrangements are possible. In some examples, the motors <NUM> are brushless DC servomotors and two or more internal Hall-effect sensors may be spaced <NUM> degrees, <NUM> degrees, or any other suitable spacing from each other around the rotor <NUM>. The sensors S may also comprise absolute or incremental encoders, which may be used to detect a rotational position of the rotor <NUM> and to count turns of the rotor <NUM>. Other type of encoders may be also used as the one or more sensors. The sensors may be placed at any suitable location on the actuator and its surrounding components suitable to determine the position of each actuator as it is adjusted, such as on the housing, nut, screw, etc. In yet another configuration, sensorless motor control may be utilized. In such an implementation, the position of each rotor may be determined by measuring the motor's back-emf and/or inductance. One suitable example may be found in <CIT>.

In some examples, output signals from the Hall-effect sensors are sent to the instrument controller <NUM>. The instrument controller <NUM> monitors the received signals for changes in their levels. Based on these signals the instrument controller <NUM> determines rotor position. Rotor position may be considered the degrees of rotation of the rotor <NUM> from an initial or home position. The rotor <NUM> can undergo plural <NUM>° rotations. The rotor position can therefore exceed <NUM>°. A scalar value referred to as a count is representative of rotor position from the home position. The rotors <NUM> rotate in both clockwise and counterclockwise directions. Each time the signal levels of the plural signals (analog or digital) undergo a defined state change, the instrument controller <NUM> increments or decrements the count to indicate a change in rotor position. For every complete <NUM>° rotation of the rotor <NUM>, the instrument controller <NUM> increments or decrements the value of the count by a fixed number of counts. In some examples, the count is incremented or decremented between <NUM> and <NUM>,<NUM> per <NUM>-degree revolution of the rotor <NUM>. In some examples, there are <NUM>,<NUM> positions (counts) per <NUM>-degree revolution of the rotor <NUM>, such as when an incremental encoder is used to monitor rotor position. Internal to the instrument controller <NUM> is a counter associated with each actuator <NUM>, <NUM>. The counter stores a value equal to the cumulative number of counts incremented or decremented. The count value can be positive, zero or negative. In some versions, the count value defines incremental movement of the rotor <NUM>. Accordingly, the rotors <NUM> of the actuators <NUM>, <NUM> may first be moved to known positions, referred to as their home positions (described further below), with the count values being used thereafter to define the current positions of the rotors <NUM>.

Each of the lead screws <NUM> are threadably connected with carriers <NUM>. The carriers <NUM> have the internally threaded bores <NUM> to receive the lead screws <NUM> so that each of the lead screws <NUM> may translate a corresponding one of the carriers <NUM> to adjust the effective length of a corresponding one of the plurality of actuators <NUM>, <NUM> and thereby vary the counts measured by the instrument controller <NUM>. The lead screws <NUM> rotate allowing the carriers <NUM> to extend and contract relative to the hand-held portion <NUM> and the actuator motor <NUM>. The carriers <NUM> are integrated into the ball stud <NUM> extending from each of the actuators <NUM>, <NUM>. Each of the housings <NUM> and corresponding carriers <NUM> are constrained from relative movement in at least one degree of freedom to allow the lead screws <NUM> to rotate relative to the carriers <NUM>. In some examples, as shown in <FIG>, the carrier includes one or more rails <NUM> which are received in complimentary slots <NUM> in the actuator motor housing <NUM>. The rails <NUM> and complimentary slots <NUM> allow the lead screws <NUM> to raise and lower the carriers <NUM> which are connected with the ball studs <NUM>, effectively translating each carrier <NUM> in the longitudinal direction when actuated (i.e. see directional arrow in <FIG>). More specifically, the lead screws <NUM> are able to rotate relative to the carriers <NUM> owing to: the ball studs <NUM> being unable to rotate about the associated active axes AA1, AA2 (i.e., the ball studs <NUM> are limited from such rotational movement by virtue of the configuration of the first active joints <NUM>, particularly retainer <NUM> within the socket mount <NUM> and complimentary groove <NUM> on ball stud <NUM> - see <FIG>, <FIG>); and the carriers <NUM> being unable to rotate about the associated active axes AA1, AA2 (i.e., the carriers <NUM> are limited from such rotational movement by virtue of the configuration of the rails <NUM> and complimentary slots <NUM>). In other examples, other methods of restraining rotational movement of the first active joint <NUM> and carriers <NUM> relative to the actuator motors <NUM> are contemplated.

As previously described, the actuators <NUM>, <NUM> are actively adjustable in effective length to enable movement of the trajectory assembly <NUM> relative to the hand-held portion <NUM>. One example of this effective length is labeled "EL" on t actuator <NUM> in <FIG>. Here, the effective length EL is measured from a center of the associated carrier <NUM> to a center of the associated first active joint <NUM>. As each actuator <NUM>, <NUM> is adjusted, the effective length EL changes, by varying how far the lead screw <NUM> has been threaded into or out of its associated carrier <NUM> and thereby changing the distance from the center of the associated carrier <NUM> to the center of the associated first active joint <NUM>. The actuators <NUM>, <NUM> are adjustable between minimum and maximum values of the effective length EL. The effective length EL of each actuator <NUM>, <NUM> can be represented/measured in any suitable manner to denote the distance between the guide member <NUM> and the hand-held portion <NUM> along the active axes AA1, AA2 that changes to cause various movements of the trajectory assembly <NUM> relative to the hand-held portion <NUM>.

The constraint assembly <NUM> works in concert with the actuators <NUM>, <NUM> to constrain the movement provided by the actuators <NUM>, <NUM>. The actuators <NUM>, <NUM> provide movement in two degrees of freedom, while the constraint assembly <NUM> constrains movement in three degrees of freedom. In the version shown, the constraint assembly <NUM> comprises the pivot frame <NUM>, as well as a shaft <NUM> that couples the pivot frame <NUM> to the base <NUM> of the hand-held portion <NUM>. The shaft <NUM> operatively interconnects the pivot frame <NUM> and the hand-held portion <NUM> independently of the actuators <NUM>, <NUM>.

In one version, as shown in <FIG> and <FIG>, the actuators <NUM>, <NUM> are displayed in different positions, showing the guide member <NUM> with different trajectories. In <FIG>, the actuators <NUM> and <NUM> are shown at a center position resulting in the guide member <NUM> being centered within the pivot frame <NUM> with a trajectory perpendicular to a bottom surface of the pivot frame <NUM>. <FIG> show actuators <NUM>, <NUM> moved into separate positions, adjusting the trajectory of the guide member <NUM>. As each actuator is energized, the actuator motor <NUM> rotates the lead screw <NUM> within the carriers <NUM>, pushing or pulling the ball studs <NUM>, and subsequently the control arms <NUM>, changing the trajectory of the guide member <NUM>. The pivot frame <NUM> allows the guide member <NUM> to pivot while preventing rotation of the guide member <NUM>. As a result, the guide member <NUM> is able to move in two degrees of freedom relative to the base <NUM> of the hand-held portion <NUM>.

The guide member <NUM> pivots within the pivot frame <NUM> when the actuators <NUM>, <NUM> are actuated. The guide member <NUM> is retained within the pivot frame <NUM> so that the guide member <NUM> does not rotate about the trajectory axis TA while adjusting its trajectory. In one example, as shown in <FIG>, the guide member <NUM> is retained into a bore of the pivot frame <NUM> and retained by a deformable seal and an anti-rotation assembly. The anti-rotation assembly may also be called a retention assembly. In one example, the deformable seal may be an O-ring and the anti-rotation assembly may be a protrusion extending into the bore of the pivot frame <NUM> with a complimentary receiver on the outer surface of the guide member (i.e. a finger and groove arrangement). The outer surface of the guide member may be shaped to contact and receive the deformable seal and the anti-rotation assembly. However, any suitable features for retaining the guide member within the pivot frame and preventing unconstrained rotation about the trajectory axis are contemplated.

In the version shown, the actuators <NUM>, <NUM> are arranged such that the active axes AA1, AA2 are in a parallel configuration in all positions of the actuators <NUM>, <NUM>, including when in their centered positions. Keeping the axes AA1, AA2 parallel generally keeps the actuator arrangement in a manner that allows for a slimmer base <NUM> and associated grip <NUM>. Other configurations are contemplated, including those in which the active axes AA1, AA2 are in a canted configuration.

Further configurations of the actuators, active joints, and constraint assembly are possible. In some versions, the constraint assembly may be absent and the trajectory assembly <NUM> of the instrument <NUM> may be able to move in additional degrees of freedom relative to the hand-held portion <NUM>. Furthermore, as mentioned above, the actuator assemblies described below may be used.

Turning to <FIG>, an alternative configuration of the instrument <NUM>' is shown, including a positioning assembly <NUM> including a plurality of positioning actuators <NUM>, <NUM>, <NUM> operatively connected with the hand-held portion <NUM>', the trajectory assembly <NUM>', including the trajectory actuators <NUM>', <NUM>, the constraint assembly <NUM>' with pivot frame <NUM>', and guide member <NUM>'. The positioning assembly <NUM> is configured to adjust a pose the trajectory assembly <NUM>' in at least three degrees of freedom, while the trajectory assembly <NUM>' is configured to adjust the guide member <NUM>' to a target trajectory with the trajectory actuators <NUM>', <NUM>, adjusting the trajectory axis of the guide member in at least two degrees of freedom to align the trajectory axis TA with the target trajectory.

Turning to <FIG> and <FIG>, the instrument <NUM>' includes the hand-held portion <NUM>' to be held by the user. The hand-held portion <NUM>' is the portion of the instrument <NUM>' which a user holds and manually supports through gripping the hand-holdable body <NUM>'. The hand-held portion <NUM>' allows the user to move and manipulate the instrument <NUM>' without constraint. The positioning assembly <NUM> is movably coupled to the hand-held body <NUM>'. A first positioning actuator <NUM> and a second positioning actuator <NUM>, along with a pivot member <NUM>, are located between the hand-held portion <NUM>' and an adjustment base <NUM>, operatively interconnecting the hand-held portion <NUM>' and the positioning assembly <NUM>. The positioning actuators <NUM>, <NUM> may be substantially similar in composition and function to the trajectory actuators <NUM>, <NUM> described above with reference to <FIG>. The positioning actuators <NUM>, <NUM> may be configured to adjust pitch and roll of the trajectory assembly <NUM>. The positioning actuators <NUM>, <NUM> are connected to the hand-held portion <NUM>' at active joints <NUM> and to the adjustment base <NUM> at active joints <NUM>. The pivot member <NUM> is fixed to hand-held portion <NUM> and does not move relative to the hand-held portion <NUM>'. Rather, the pivot member <NUM> is connected to the adjustment base <NUM> at active joint <NUM>, configured as a ball-and-socket connection, the connection end of the pivot member <NUM> having the ball, and the adjustment plate <NUM> having the receiving socket.

The positioning actuators <NUM>, <NUM>, in the version shown, comprise electric, linear actuators that extend between the hand-held portion <NUM> and the adjustment plate. When actuated, an effective length of the actuator <NUM>, <NUM> changes to vary a distance between the hand-held portion <NUM>' and the adjustment plate <NUM> along a corresponding axis of the positioning actuators <NUM>, <NUM> (<FIG>). Accordingly, the actuators <NUM>, <NUM> work in concert to change their effective lengths and move the positioning assembly <NUM> in at least three degrees of freedom relative to the hand-held portion <NUM>'. The positioning actuators <NUM>, <NUM> are adjustable in effective length along a first active axis AA1' and a second active axis AA2' (see <FIG>). The first and second positioning actuators <NUM>, <NUM> are independently adjustable in effective length to adjust one or more of a pitch orientation, and a roll orientation. The actuators <NUM>, <NUM> may comprise rotary actuators in some examples. The actuators <NUM>, <NUM> may comprise linkages having one or more links of any suitable size or shape. The positioning actuators <NUM>, <NUM> may have any configuration suitable to enable movement of the positioning assembly <NUM> to move the trajectory assembly <NUM>' relative to the hand-held portion <NUM>' in at least three degrees of freedom.

In this version, the positioning actuators <NUM>, <NUM> are coupled to the adjustment base <NUM> and the hand-held portion <NUM>' via a plurality of active joints <NUM>, <NUM>. The active joints include a set of first active joints <NUM> that couple the actuators <NUM>, <NUM> to the hand-held portion <NUM>' at the actuator mounts <NUM>. In one version, as shown in <FIG>, the first active joints <NUM> comprises active spherical joints. The spherical joints comprise a socket connector <NUM>. The socket connector <NUM> pivotally connects the actuator mounts <NUM> with a spherical stud <NUM> of the actuators <NUM>, <NUM>. As a result, the actuators <NUM>, <NUM> are able to move the positioning assembly <NUM> (and subsequently the trajectory assembly <NUM>) in at least three degrees of freedom relative to the hand-held portion <NUM>. Other types of active joints are also contemplated, such as active joint blocks comprising U-joints that receive pins.

Referring to <FIG>, the active joints also comprise a set of second active joints <NUM> coupling the positioning actuators <NUM>, <NUM> to the adjustment base <NUM>. In the version shown, the second active joints <NUM> are supported at the joint supports <NUM>. Each of the second active joints <NUM> comprises a spherical joint arranged to pivot relative to the adjustment base <NUM>. Each spherical joint has a ball stud <NUM> extending from the actuators <NUM>, <NUM> to pivotally engage the socket mount <NUM> in the adjustment base <NUM>, allowing the respective actuators <NUM>, <NUM> to pivot within the active joint <NUM> moving the positioning assembly <NUM> relative to the hand-held portion <NUM>', changing the position of the trajectory assembly <NUM>'.

As shown in <FIG>, the positioning actuators <NUM>, <NUM> and the pivot member <NUM> are arranged in a parallel configuration, canted relative to the hand-held portion <NUM> and the longitudinal axis of the instrument <NUM>. The positioning actuators <NUM>, <NUM> and pivot member <NUM> are arranged in a generally triangular shape with the pivot member <NUM> in a forward position and the positioning actuators <NUM>, <NUM> in rear positions. The positioning assembly further includes a translation actuator <NUM> arranged along the longitudinal axis of the instrument <NUM>. The translation actuator <NUM> is connected with the adjustment base <NUM>, opposite of the positioning actuators <NUM>, <NUM> and pivot member <NUM>. The translation actuator <NUM> may be configured to control the longitudinal translation of the trajectory assembly <NUM>'.

The positioning assembly <NUM> is configured to move the trajectory assembly <NUM>' in three degrees of freedom, changing the z-axis translation (longitudinal translation relative to the hand-held portion <NUM>'), pitch, and roll relative to the hand-held portion <NUM>'. The positioning assembly is connected to the trajectory assembly <NUM> through the translation actuator <NUM>. The translation actuator is substantially similar to the positioning actuators <NUM>, <NUM> and the trajectory actuators <NUM>', <NUM>, operating in a substantially similar fashion. The translation actuator <NUM> changes effective length EL along an active axis AA3 (<FIG>). The translation actuator <NUM> does not connect with an active joint, but rather is fixed between the positioning assembly and the trajectory assembly <NUM>', translating the trajectory assembly <NUM>' relative to the positioning assembly <NUM> and the hand-held portion <NUM>'.

As best shown in <FIG>, the trajectory assembly <NUM>' comprises a trajectory base <NUM> which is operatively connected to the translation actuator <NUM> of the positioning assembly <NUM>, as well as the constraint assembly <NUM>' and trajectory actuators <NUM>', <NUM>'.

As described above, the trajectory actuators <NUM>', <NUM>, in the version shown, comprise electric, linear actuators that extend between the trajectory base and the control arms <NUM>' of the guide member <NUM>'. When actuated, an effective length of the actuator <NUM>', <NUM>' changes to vary a distance between the guide member <NUM>' and a trajectory base <NUM> along a corresponding axis of the trajectory actuators <NUM>', <NUM>'. Accordingly, the actuators <NUM>', <NUM>' work in concert to change their effective lengths and move the trajectory assembly <NUM>' in at least two degrees of freedom relative to the hand-held portion <NUM>' and the positioning assembly. In the version shown, two trajectory actuators <NUM>', <NUM>' are provided, and may be referred to as first and second trajectory actuators <NUM>', <NUM>' or trajectory assembly actuators <NUM>', <NUM>'. The trajectory actuators <NUM>', <NUM>'are adjustable in effective length along active axis AA4 and active axis AA5 (see <FIG>). The first and second actuators <NUM>', <NUM>' are independently adjustable in effective length to adjust one or more of a pitch orientation and a roll orientation of the guide member <NUM>' relative to the hand-held portion <NUM>', as previously described. The actuators <NUM>', <NUM>' may comprise rotary actuators in some examples. The actuators <NUM>', <NUM>' may comprise linkages having one or more links of any suitable size or shape. The actuators <NUM>', <NUM>' may have any configuration suitable to enable movement of the guide member <NUM>' relative to the hand-held portion <NUM>' and the positioning assembly <NUM> in at least two degrees of freedom.

In this version, the trajectory actuators <NUM>', <NUM>' are coupled to the trajectory base <NUM> and the control arms <NUM>' of the guide member <NUM>' via a plurality of active joints. The active joints include a set of first active trajectory joints <NUM>' that couple the actuators <NUM>', <NUM>' to the trajectory base <NUM> at the actuator mounts <NUM>', <NUM>'. In one version, as shown in <FIG>, the first active joints <NUM>' comprises active spherical joints <NUM>'. The spherical joints <NUM>' comprise a socket connector <NUM>'. The first socket connector <NUM>' pivotally connects the actuator mounts <NUM>', <NUM>' with a spherical stud <NUM>' of the actuators <NUM>', <NUM>'. As a result, the actuators <NUM>', <NUM>' are able to move the guide member <NUM>' in at least two degrees of freedom relative to the translation actuator <NUM> and positioning assembly <NUM>. Other types of active joints are also contemplated, such as active joint blocks comprising U-joints that receive pins.

Referring to <FIG>, the active joints also comprise a set of second active joints <NUM>' coupling the trajectory actuators <NUM>', <NUM>' to the control arms <NUM>' of the guide member <NUM>'. In the version shown, the second active joints <NUM>' are supported at the joint supports <NUM>', <NUM>'. Each of the second active joints <NUM>' comprises a spherical joint <NUM>' arranged to pivot relative to the control arms <NUM>' of the guide member <NUM>'. Each spherical joint <NUM>' has a ball stud <NUM>' extending from the actuators <NUM>', <NUM>' to pivotally engage the socket mount <NUM>' in each of the control arms <NUM>' at one of the joint supports <NUM>', <NUM>' allowing the respective actuators <NUM>', <NUM>' to pivot within its respective joint support <NUM>', <NUM>' moving the guide member <NUM>' relative to the hand-held portion <NUM>' and positioning assembly <NUM>.

The constraint assembly <NUM>' works in concert with the trajectory actuators <NUM>', <NUM>' to constrain the movement of the guide member <NUM>' provided by the actuators <NUM>', <NUM>'. The actuators <NUM>', <NUM>' provide movement in two degrees of freedom, while the constraint assembly <NUM>' constrains movement in three degrees of freedom. In the version shown, the constraint assembly <NUM>' comprises the pivot frame <NUM>', as well as a shaft <NUM>' that couples the pivot frame <NUM>' to the base <NUM>' of the hand-held portion <NUM>'. The guide member <NUM>' comprises control arms <NUM>'. Each control arm <NUM>' including an actuator mount <NUM>', <NUM>' at which the actuators <NUM>', <NUM>' are to be movably coupled to the control arms <NUM>' of the guide member <NUM>' via joints. The actuator mounts <NUM>', <NUM>', may comprise brackets, or the like, suitable to mount the actuators <NUM>', <NUM>' such that the trajectory assembly <NUM>' is able to move in at least two degrees of freedom relative to the positioning assembly <NUM>.

As shown in <FIG>, the actuators <NUM>', <NUM>, <NUM>, <NUM>, <NUM> are displayed in different positions, showing the positioning assembly <NUM> and trajectory assembly <NUM>' in different positions. In <FIG>, the actuators <NUM>', <NUM>, <NUM>, <NUM>, <NUM> are shown at a center position resulting in a neutral position of the instrument <NUM>'. The guide member <NUM>' is centered within the pivot frame <NUM>' with a trajectory perpendicular to a bottom surface of the pivot frame <NUM>'.

The guide member <NUM>' pivots within the pivot frame <NUM>' when the actuators <NUM>', <NUM>' are actuated. The guide member <NUM>' is retained within the pivot frame <NUM>' so that the guide member <NUM>' does not rotate about the trajectory axis TA while adjusting its trajectory.

Referring back to <FIG>, the guide member <NUM> is retained into a bore of the pivot frame <NUM> and retained by a deformable seal <NUM> and an anti-rotation assembly <NUM>. In one example, the deformable seal <NUM> may be an O-ring and the anti-rotation assembly <NUM> may include a protrusion <NUM> extending into the bore <NUM> of the pivot frame <NUM> with a complimentary receiver <NUM> on the outer surface of the guide member <NUM>. The outer surface of the guide member <NUM> may be shaped to contact and receive the deformable seal <NUM> and the anti-rotation assembly <NUM>. However, any suitable features for retaining the guide member <NUM> within the pivot frame <NUM> and preventing rotation about the trajectory axis are contemplated.

In the version shown, the positioning actuators <NUM>, <NUM> and the trajectory actuators <NUM>', <NUM>' are arranged such that the active axes AA1', AA2' and AA4, AA5 are in a parallel configuration, respectively, in all positions, including when in the actuators are in the centered position. Keeping the axes AA1', AA2' and AA4, AA5 parallel generally keeps the actuator arrangement in line and allows for a slimmer base <NUM>'. Additionally, the configuration of the actuators <NUM>', <NUM>', <NUM>, <NUM> allows for greater adjustment of the trajectory assembly <NUM>' and guide member <NUM>'.

<FIG> show actuators <NUM>, <NUM> adjusting the position of the instrument <NUM>' into a right disposition. The positioning assembly <NUM> is moved to the right when actuator <NUM> is extended and actuator <NUM> is retracted. The positioning assembly <NUM> moves the adjustment base <NUM>, changing the position of the trajectory assembly <NUM>'. The trajectory actuators <NUM>', <NUM>' compensate for the right disposition, adjusting the trajectory of the guide member <NUM>' by extending actuator <NUM>' and retracting actuator <NUM>', causing the guide arms <NUM>' to adjust the guide member <NUM>' into a trajectory substantially matching the angle at which the hand-held portion <NUM> is positioned. Similarly, <FIG> show the instrument <NUM>' with a left disposition. The positioning assembly <NUM> has positioned the adjustment base <NUM> to the left by extending actuator <NUM> and retracting actuator <NUM>. The trajectory assembly <NUM>' adjusts actuator <NUM>' to retract, pulling one of the guide arms <NUM>' up and expands actuator <NUM>' pushing the other guide arm <NUM>' down. The guide member <NUM>' is subsequently moved to the desired trajectory relative to the position of the hand-held portion <NUM>'.

Turning to <FIG> and <FIG>, the positioning actuators <NUM>, <NUM> are in a centered position. Figures 18A-8C depict the translation actuator <NUM> in an extended position, causing the trajectory assembly to be tilted forward. To compensate for the forward tilt, the trajectory assembly actuators <NUM>', <NUM>' are retracted, adjusting the guide member <NUM>' towards the trajectory assembly <NUM>', maintaining a trajectory which is perpendicular. Similarly, <FIG> depict the translation actuator <NUM> in a fully retracted position causing the trajectory assembly <NUM>' to be tilted backwards. To compensate for the movement, the trajectory actuators <NUM>', <NUM>' are extended, pushing the control arms <NUM>' down, causing the guide member <NUM>' to adjust to a perpendicular trajectory.

Further configurations of the positioning assembly, trajectory assembly, actuators, active joints, and constraint assembly are possible. In some versions, the constraint assembly may be absent and the trajectory assembly <NUM>' of the instrument <NUM>' may be able to move in additional degrees of freedom relative to the hand-held portion <NUM>'.

The software employed by the control system <NUM> to control operation of the instrument <NUM> includes a boundary generator <NUM> (see <FIG>). The boundary generator <NUM> may be implemented on the instrument controller <NUM>, the navigation controller <NUM>, and/or on other components, such as on a separate controller. The boundary generator <NUM> may also be part of a separate system that operates remotely from the instrument <NUM>. Referring to Figure <NUM>, the boundary generator <NUM> is a software program or module that generates one or more virtual boundaries <NUM> for constraining movement and/or operation of the instrument <NUM>. Virtual boundaries <NUM> may be provided to delineate various operational/control regions as described below. The virtual boundaries <NUM> may be one-dimensional (1D), two-dimensional (2D), three-dimensional (3D), and may comprise a point, line, axis, trajectory, plane (an infinite plane or plane segment bounded by the anatomy or other boundary), volume or other shapes, including complex geometric shapes. The virtual boundaries <NUM> may be represented by pixels, point clouds, voxels, triangulated meshes, other 2D or 3D models, combinations thereof, and the like. The features described in <CIT> and <CIT> may be used to facilitate planning or execution of the surgical procedure.

The virtual boundaries <NUM> may be used in various ways. For example, the control system <NUM> may: control certain movements of the guide member <NUM> to stay inside the boundary; control certain movements of the guide member <NUM> to stay outside the boundary; control certain movements of the guide member <NUM> to stay on the boundary (e.g., stay on a point and/or trajectory); control certain movements of the guide member <NUM> to approach the boundary (attractive boundary) or to be repelled from the boundary (repulsive boundary); and/or control certain operations/functions of the instrument <NUM> based on a relationship of the instrument <NUM> to the boundary (e.g., spatial, velocity, etc.). Other uses of the boundaries <NUM> are also contemplated.

In some examples, one of the virtual boundaries <NUM> is a desired trajectory, as shown in <FIG>. The control system <NUM> will ultimately function to keep the guide member <NUM> on the desired trajectory in some versions. The virtual boundary <NUM> that controls positioning of the guide member <NUM> may also be a volumetric boundary, such as one having an area slightly larger than a drill, pedicle screw, and/or pin to constrain the guided utensil to stay within the boundary and on a desired trajectory, as shown in <FIG>. Therefore, the desired trajectory can be defined by a virtual line segment boundary, a virtual volumetric boundary, or other forms of virtual boundary. Virtual boundaries <NUM> may also be referred to as virtual objects. The virtual boundaries <NUM> may be defined with respect to an anatomical model AM, such as a 3D bone model (see <FIG>, which illustrates the anatomical model AM being virtually overlaid on the actual humerus H due to their registration). In other words, the points, lines, axes, trajectories, planes, volumes, and the like, that are associated with the virtual boundaries <NUM> may be defined in a coordinate system that is fixed relative to a coordinate system of the anatomical model AM such that tracking of the anatomical model AM (e.g., via tracking the associated anatomy to which it is registered) also enables tracking of the virtual boundary <NUM>.

The anatomical model AM is registered to the first patient tracker <NUM> such that the virtual boundaries <NUM> become associated with the anatomical model AM and associated coordinate system. The virtual boundaries <NUM> may be implant-specific, e.g., defined based on a size, shape, volume, etc. of an implant and/or patient-specific, e.g., defined based on the patient's anatomy. The virtual boundaries <NUM> may be boundaries that are created pre-operatively, intra-operatively, or combinations thereof. In other words, the virtual boundaries <NUM> may be defined before the surgical procedure begins, during the surgical procedure (including during tissue removal), or combinations thereof. The virtual boundaries <NUM> may be provided in numerous ways, such as by the control system <NUM> creating them, receiving them from other sources/systems, or the like. The virtual boundaries <NUM> may be stored in memory for retrieval and/or updating.

In some cases, such as when preparing the humerus H for receiving the shoulder implant IM as in <FIG>, the virtual boundaries <NUM> comprise multiple planar boundaries that can be used to delineate multiple trajectories (e.g., four trajectories to secure the implant to the scapula SC) for the shoulder implant IM, and are associated with a 3D model of the distal end of the scapula SC. In one example, such as in <FIG>, these multiple virtual boundaries <NUM> can be activated, one at a time, by the control system <NUM> to constrain cutting to one plane at a time.

The instrument controller <NUM> and/or the navigation controller <NUM> track the state of the guide member <NUM> relative to the virtual boundaries <NUM>. In one example, the state of the TCP coordinate system (e.g., pose of the guide member) is measured relative to the virtual boundaries <NUM> for purposes of determining target positions for the actuators <NUM>, <NUM> so that the guide member <NUM> remains in a desired state.

Referring back to <FIG>, two additional software programs or modules run on the instrument controller <NUM> and/or the navigation controller <NUM>. One software module performs behavior control <NUM>. Behavior control <NUM> is the process of computing data that indicates the next commanded/desired position and/or orientation (e.g., desired pose) for the guide member <NUM>. In some cases, only the desired position of the TCP is output from the behavior control <NUM>, while in some cases, the commanded pose of the guide member <NUM> is output. Output from the boundary generator <NUM> (e.g., a current position and/or orientation of the virtual boundaries <NUM> in one or more of the coordinate systems) may feed as inputs into the behavior control <NUM> to determine the next commanded position of the actuators <NUM>, <NUM> and/or orientation for the guide member <NUM>. The behavior control <NUM> may process this input, along with one or more other inputs described further below, to determine the commanded pose.

The instrument controller <NUM> may control the one or more actuators <NUM>, <NUM> by sending command signals to each actuator <NUM>, <NUM> to adjust the guide member <NUM> towards a desired pose. The instrument controller <NUM> may know the entire length that an actuator <NUM>, <NUM> may adjust the trajectory assembly18 relative to the hand-held portion <NUM>. In some examples, the instrument controller <NUM> knows the entire length which an actuator <NUM>, <NUM> is capable of adjusting and may send command signals to the actuators <NUM>, <NUM> to move a measured distance from position to position. A measured position may be a known position, or a distance between the present location of an actuator <NUM>, <NUM> and the actuator limits. Each position that the actuator <NUM>, <NUM> moves to may be a measured distance from a positive limit and a negative limit of actuator travel (i.e. a position between two ends of a lead screw). The instrument controller <NUM> may command the actuators <NUM>, <NUM> to and from measured positions as described below.

The instrument controller <NUM> may send command signals to each actuator <NUM>, <NUM> to move the actuators <NUM>, <NUM> from a first position to a commanded position which will place the guide member <NUM> into a desired pose. In some examples, the commanded position may be determined by the instrument controller <NUM> in conjunction with the navigation system <NUM> to determine the location of the guide member <NUM> and trajectory assembly <NUM> relative to the hand-held portion <NUM>, patient trackers PT, <NUM>, <NUM>, a virtual object, such as desired trajectory or a combination thereof and send a signal to the actuators <NUM>, <NUM> to adjust a certain distance in order to place the guide member <NUM> into the desired pose. The instrument controller may command the actuator <NUM>, <NUM> to a position in order to reach the desired adjustment of the guide member <NUM>. The instrument controller <NUM> may control the actuators <NUM>, <NUM> to linearly move a calculated distance to adjust the guide member <NUM> towards a desired pose to provide for a desired trajectory. In other examples, such as when absolute encoders are used, the instrument controller may send signals to the actuators <NUM>, <NUM> to place each actuator <NUM>, <NUM> into the desired position based on the known location of the trajectory assembly <NUM> relative to the hand-held portion <NUM> determined by the absolute encoder.

In some examples, when one or more of the actuators <NUM>, <NUM> have reached their limit, the instrument controller <NUM> may require the hand-held portion <NUM> to be adjusted in order to bring the guide member <NUM> back into a range where the actuators are capable of adjusting the guide member <NUM> towards the desired pose and trajectory. The instrument may include a user interface UI on the display <NUM>, an optional guidance array or both to signal to a user that the hand-held portion <NUM> needs to be moved in particular way to place the guide member <NUM> at the desired pose. In some examples, user interface UI on the display <NUM>, the optional guidance array, or both to signal to a user to move the hand-held portion <NUM> in the same fashion as if the actuators <NUM>, <NUM> were adjusting the guide member <NUM>, but relies on the user to correct the position of the guide member <NUM> by manipulating the hand-held portion <NUM> while the actuators remain in the target orientation holding the desired trajectory.

The second software module performs motion control <NUM>. One aspect of motion control <NUM> is the control of the instrument <NUM>. The motion control <NUM> receives data defining the target pose from the behavior control <NUM>. Based on these data, the motion control <NUM> determines the next rotor position of the rotors <NUM> of each actuator <NUM>, <NUM> (e.g., via inverse kinematics) so that the instrument <NUM> is able to position the guide member <NUM> as commanded by the behavior control <NUM>. In one version, the motion control <NUM> regulates the rotor position of each motor <NUM> and continually adjusts the torque that each motor <NUM> outputs to, as closely as possible, ensure that the motor <NUM> drives the associated actuator <NUM>, <NUM> to the target rotor position.

In some versions, the instrument controller <NUM>, for each actuator <NUM>, <NUM> determines the difference between a measured position and a target position of the rotor <NUM>. The instrument controller <NUM> outputs a target current (proportional to a torque of the rotor), changing the voltage to adjust the current at the actuator from an initial current to the target current. The target current effectuates a movement of the actuators <NUM>, <NUM> moving the guide member <NUM> from the measured pose to the target pose. This may occur after the target pose is converted to joint positions. In one example, the measured position of each rotor <NUM> may be derived from the sensor S described above, such as an encoder.

The boundary generator <NUM>, behavior control <NUM>, and motion control <NUM> may be sub-sets of a software program. Alternatively, each may be software programs that operate separately and/or independently in any combination thereof. The term "software program" is used herein to describe the computer-executable instructions that are configured to carry out the various capabilities of the technical solutions described. For simplicity, the term "software program" is intended to encompass, at least, any one or more of the boundary generator <NUM>, behavior control <NUM>, and/or motion control <NUM>. The software program can be implemented on the instrument controller <NUM>, navigation controller <NUM>, or any combination thereof, or may be implemented in any suitable manner by the control system <NUM>.

A clinical application <NUM> may be provided to handle user interaction. The clinical application <NUM> handles many aspects of user interaction and coordinates the surgical workflow, including pre-operative planning, implant placement and retention, registration, bone preparation visualization, and post-operative evaluation of implant fit, etc. The clinical application <NUM> is configured to output to the displays <NUM>. The clinical application <NUM> may run on its own separate processor or may run alongside the instrument controller <NUM> and/or the navigation controller <NUM>. In one example, the clinical application <NUM> interfaces with the boundary generator <NUM> after implant placement is set by the user, and then sends the virtual boundaries <NUM> returned by the boundary generator <NUM> to the instrument It should be appreciated that other types of feedback could be employed to help guide the user, such as audible, tactile (e.g., vibrations), or the like. Other types of visual feedback could also be employed, such as using augmented reality techniques, projecting light onto the anatomy, or the like.

In this application, including the definitions below, the term "controller" may be replaced with the term "circuit. " The term "controller" may refer to, be part of, or include: an Application Specific Integrated Circuit (ASIC); a digital, analog, or mixed analog/digital discrete circuit; a digital, analog, or mixed analog/digital integrated circuit; a combinational logic circuit; a field programmable gate array (FPGA); a processor circuit (shared, dedicated, or group) that executes code; a memory circuit (shared, dedicated, or group) that stores code executed by the processor circuit; other suitable hardware components that provide the described functionality; or a combination of some or all of the above, such as in a system-on-chip.

The controller(s) may include one or more interface circuits. In some examples, the interface circuit(s) may implement wired or wireless interfaces that connect to a local area network (LAN) or a wireless personal area network (WPAN). Examples of a LAN are Institute of Electrical and Electronics Engineers (IEEE) Standard <NUM>-<NUM> (also known as the WIFI wireless networking standard) and IEEE Standard <NUM>-<NUM> (also known as the ETHERNET wired networking standard). Examples of a WPAN are the BLUETOOTH wireless networking standard from the Bluetooth Special Interest Group and IEEE Standard <NUM>.

The controller may communicate with other controllers using the interface circuit(s). Although the controller may be depicted in the present disclosure as logically communicating directly with other controllers, in various configurations the controller may actually communicate via a communications system. The communications system includes physical and/or virtual networking equipment such as hubs, switches, routers, and gateways. In some configurations, the communications system connects to or traverses a wide area network (WAN) such as the Internet. For example, the communications system may include multiple LANs connected to each other over the Internet or point-to-point leased lines using technologies including Multiprotocol Label Switching (MPLS) and virtual private networks (VPNs).

In various configurations, the functionality of the controller may be distributed among multiple controllers that are connected via the communications system. For example, multiple controllers may implement the same functionality distributed by a load balancing system. In a further example, the functionality of the controller may be split between a server (also known as remote, or cloud) controller and a client (or, user) controller.

Some or all hardware features of a controller may be defined using a language for hardware description, such as IEEE Standard <NUM>-<NUM> (commonly called "Verilog") and IEEE Standard <NUM>-<NUM> (commonly called "VHDL"). The hardware description language may be used to manufacture and/or program a hardware circuit. In some configurations, some or all features of a controller may be defined by a language, such as IEEE <NUM>-<NUM> (commonly called "SystemC"), that encompasses both code, as described below, and hardware description.

The various controller programs may be stored on a memory circuit. The term memory circuit is a subset of the term computer-readable medium. The term computer-readable medium, as used herein, does not encompass transitory electrical or electromagnetic signals propagating through a medium (such as on a carrier wave); the term computer-readable medium may therefore be considered tangible and non-transitory. Non-limiting examples of a non-transitory computer-readable medium are nonvolatile memory circuits (such as a flash memory circuit, an erasable programmable read-only memory circuit, or a mask read-only memory circuit), volatile memory circuits (such as a static random access memory circuit or a dynamic random access memory circuit), magnetic storage media (such as an analog or digital magnetic tape or a hard disk drive), and optical storage media (such as a CD, a DVD, or a Blu-ray Disc).

The apparatuses and methods described in this application may be partially or fully implemented by a special purpose computer created by configuring a general purpose computer to execute one or more particular functions embodied in computer programs. The functional blocks and flowchart elements described above serve as software specifications, which can be translated into the computer programs by the routine work of a skilled technician or programmer.

The computer programs include processor-executable instructions that are stored on at least one non-transitory computer-readable medium. The computer programs may also include or rely on stored data. The computer programs may encompass a basic input/output system (BIOS) that interacts with hardware of the special purpose computer, device drivers that interact with particular devices of the special purpose computer, one or more operating systems, user applications, background services, background applications, etc..

The computer programs may include: (i) descriptive text to be parsed, such as HTML (hypertext markup language), XML (extensible markup language), or JSON (JavaScript Object Notation), (ii) assembly code, (iii) object code generated from source code by a compiler, (iv) source code for execution by an interpreter, (v) source code for compilation and execution by a just-in-time compiler, etc. As examples only, source code may be written using syntax from languages including C, C++, C#, Objective C, Swift, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl, Pascal, Curl, OCaml, JavaScript®, HTML5 (Hypertext Markup Language 5th revision), Ada, ASP (Active Server Pages), PHP (PHP: Hypertext Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, Visual Basic®, Lua, MATLAB, SENSORLINK, and Python® controller <NUM> for execution.

It should be understood that the combination of position and orientation of an object is referred to as the pose of the object. Throughout this disclosure, it is contemplated that the term pose may be replaced by position and/or orientation in one or more degrees of freedom and vice-versa to achieve suitable alternatives of the concepts described herein. In other words, any use of the term pose can be replaced with position and any use of the term position may be replaced with pose.

The methods in accordance with the present teachings is for example a computer implemented method. For example, all the steps or merely some of the steps (i.e. less than the total number of steps) of the method in accordance with the present teachings can be executed by a computer (for example, at least one computer). A configuration of the computer implemented method is a use of the computer for performing a data processing method. Further, in the present teachings, the methods disclosed herein comprise executing, on at least one processor of at least one computer (for example at least one computer being part of the navigation system), the following exemplary steps which are executed by the at least one processor.

The computer for example comprises at least one processor and for example at least one memory in order to (technically) process the data, for example electronically and/or optically. The processor being for example made of a substance or composition which is a semiconductor, for example at least partly n- and/or p-doped semiconductor, for example at least one of II-, III-, IV-, V-, Vl-semiconductor material, for example (doped) silicon and/or gallium arsenide. The calculating or determining steps described are for example performed by a computer. Determining steps or calculating steps are for example steps of determining data within the framework of the technical method, for example within the framework of a program. A computer is for example any kind of data processing device, for example electronic data processing device. A computer can be a device which is generally thought of as such, for example desktop PCs, notebooks, netbooks, etc., but can also be any programmable apparatus, such as for example a mobile phone or an embedded processor. A computer can for example comprise a system (network) of "sub-computers", wherein each sub-computer represents a computer in its own right. The term "computer" includes a cloud computer, for example a cloud server. The term computer includes a server resource. The term "cloud computer" includes a cloud computer system which for example comprises a system of at least one cloud computer and for example a plurality of operatively interconnected cloud computers such as a server farm. Such a cloud computer is preferably connected to a wide area network such as the world wide web (WWW) and located in a so-called cloud of computers which are all connected to the world wide web. Such an infrastructure is used for "cloud computing", which describes computation, software, data access and storage services which do not require the end user to know the physical location and/or configuration of the computer delivering a specific service. For example, the term "cloud" is used in this respect as a metaphor for the Internet (world wide web). For example, the cloud provides computing infrastructure as a service (laaS). The cloud computer can function as a virtual host for an operating system and/or data processing application which is used to execute the method of the present teachings. The cloud computer is for example an elastic compute cloud (EC2) as provided by Amazon Web Services™. A computer for example comprises interfaces in order to receive or output data and/or perform an analogue-to-digital conversion. For example, the present teachings may not involve or in particular comprise or encompass an invasive step which would represent a substantial physical interference with the body requiring professional medical expertise to be carried out and entailing a substantial health risk even when carried out with the required professional care and expertise. The data are for example data which represent physical properties and/or which are generated from technical signals. The technical signals are for example generated by means of (technical) detection devices (such as for example devices for detecting marker devices) and/or (technical) analytical devices (such as for example devices for performing (medical) imaging methods), wherein the technical signals are for example electrical or optical signals. The technical signals for example represent the data received or outputted by the computer. The computer is preferably operatively coupled to a display device which allows information outputted by the computer to be displayed, for example to a user. One example of a display device is a virtual reality device or an augmented reality device (also referred to as virtual reality glasses or augmented reality glasses. ) Another example of a display device would be a standard computer monitor comprising for example a liquid crystal display operatively coupled to the computer for receiving display control data from the computer for generating signals used to display image information content on the display device.

The present teachings also relate to a computer program comprising instructions which, when on the program is executed by a computer, cause the computer to carry out the method or methods, for example, the steps of the method or methods, described herein and/or to a computer-readable storage medium (for example, a non-transitory computer- readable storage medium) on which the program is stored and/or to a computer comprising said program storage medium and/or to a (physical, for example electrical, for example technically generated) signal wave, for example a digital signal wave, such as an electromagnetic carrier wave carrying information which represents the program, for example the aforementioned program, which for example comprises code means which are adapted to perform any or all of the method steps described herein. The signal wave is in one example a data carrier signal carrying the aforementioned computer program. The present teachings also relate to a computer comprising at least one processor and/or the aforementioned computer-readable storage medium and for example a memory, wherein the program is executed by the processor.

Within the framework of the present teachings, computer program elements can be embodied by hardware and/or software (this includes firmware, resident software, micro-code, etc.). Within the framework of the present teachings, computer program elements can take the form of a computer program product which can be embodied by a computer-usable, for example computer-readable data storage medium comprising computer-usable, for example computer-readable program instructions, "code" or a "computer program" embodied in said data storage medium for use on or in connection with the instruction executing system. Such a system can be a computer; a computer can be a data processing device comprising means for executing the computer program elements and/or the program in accordance with the present teachings, for example a data processing device comprising a digital processor (central processing unit or CPU) which executes the computer program elements, and optionally a volatile memory (for example a random access memory or RAM) for storing data used for and/or produced by executing the computer program elements. Within the framework of the present teachings, a computer-usable, for example computer-readable data storage medium can be any data storage medium which can include, store, communicate, propagate or transport the program for use on or in connection with the instruction-executing system, apparatus or device.

Several instances have been discussed in the foregoing description. However, the aspects discussed herein are not intended to be exhaustive or limit the disclosure to any particular form. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the disclosure. The terminology that has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations are possible in light of the above teachings and the disclosure may be practiced otherwise than as specifically described.

Claim 1:
A robotically-assisted handholdable guide instrument (<NUM>, <NUM>') for aligning a trajectory of a surgical device, the instrument comprising:
a hand-holdable body (<NUM>, <NUM>', <NUM>, <NUM>', <NUM>, <NUM>') adapted to be freely holdable and moved by a hand of a user; and
a trajectory assembly (<NUM>, <NUM>') operatively connected with the hand-holdable body (<NUM>, <NUM>', <NUM>, <NUM>', <NUM>, <NUM>'), the trajectory assembly (<NUM>, <NUM>') including:
a shaft (<NUM>, <NUM>') extending from the hand-holdable body (<NUM>, <NUM>', <NUM>, <NUM>', <NUM>, <NUM>');
a pivot frame (<NUM>, <NUM>') coupled with the shaft (<NUM>, <NUM>');
a guide member (<NUM>, <NUM>') pivotally connected with the pivot frame (<NUM>, <NUM>');
a support member (<NUM>, <NUM>') outwardly extending from and connected with the guide member (<NUM>, <NUM>');
two actuators (<NUM>, <NUM>', <NUM>, <NUM>') coextending and substantially parallel to an axis of the shaft (<NUM>, <NUM>'), each actuator (<NUM>, <NUM>', <NUM>, <NUM>') pivotally connected with the support member (<NUM>, <NUM>');
wherein the trajectory assembly (<NUM>, <NUM>') converts linear movement of the actuators (<NUM>, <NUM>', <NUM>, <NUM>') into pivotal movement of the guide member (<NUM>, <NUM>') to adjust a trajectory axis, the actuators (<NUM>, <NUM>', <NUM>, <NUM>') selectively configured to push and pull the support member (<NUM>, <NUM>') connected with the guide member (<NUM>, <NUM>'); and
wherein the guide member (<NUM>, <NUM>') is adjustable to a target trajectory with the actuators (<NUM>, <NUM>', <NUM>, <NUM>'), adjusting the trajectory axis of the guide member (<NUM>, <NUM>') in at least two degrees of freedom to align the trajectory axis with the target trajectory.