Configurable transmitter arrays for electromagnetic tracking systems

Abstract

A magnetic tracking system is configured to determine an object pose of a tracked object in an environment of the magnetic tracking system. The tracking system includes a transmitter accessory, which includes a transmitter coil configured to generate a magnetic signal indicating an object pose of the tracked object with respect to the transmitter accessory and a mark that visually identifies a pose of the transmitter accessory with respect to a camera device. The camera device captures at least one image of the transmitter accessory. A computing device determines a pose of the transmitter accessory in the image based on the image. Based on the magnetic signal and the pose associated with the transmitter accessory, the computing device determines the object pose of the tracked object in the environment.

Description

Technical Field

[0001] The present disclosure relates to tracking one or more objects in a magnetic field, and more particularly to a system for tracking a surgical instrument using electromagnetic (EM) signals. Background Art

[0002] Electromagnetic tracking (EMT) systems are used to aid in the positioning of instruments and anatomy during medical procedures.Such systems can determine the position of a receiver based on the measured field lines of a transmitted magnetic field. Summary of the invention

[0003] Electromagnetic tracking (EMT) systems (also referred to as magnetic tracking systems) can be used to track equipment for a variety of applications, such as for medical applications during endoscopic surgery or other types of surgical procedures. The EMT system (also referred to as a magnetic tracking system) includes at least one transmitter and at least one receiver. The transmitter, for example, emits a magnetic signal, and the receiver receives the magnetic signal and measures the magnetic signal. The measured magnetic signal provides information that the magnetic tracking system uses to determine the relative positioning of the transmitter with respect to the receiver (or vice versa). If the transmitter or receiver is attached to another device (e.g., a tracked device), the magnetic tracking system can determine the relative positioning of the tracked device in the environment of the magnetic tracking system. In some embodiments, the magnetic tracking system can detect distortion of the magnetic signal caused by metal objects in the environment. A variety of additional applications for tracking objects are known.

[0004] The magnetic tracking system described herein includes a plurality of transmitter accessories. The magnetic tracking system is configured to determine the location of one or more objects with respect to the transmitter accessories, such as by detecting a magnetic signal emitted by one or more of the plurality of transmitter accessories. The transmitter accessories are placed at different positions with respect to a receiver of the magnetic tracking system. The magnetic tracking system determines the location of the transmitter accessory relative to the transmitter by one or more non-magnetic techniques, such as by visual techniques, ultrasound, radio signals, etc. Once the location of the transmitter accessory is known, the magnetic tracking system can determine the position and orientation of the receiver.

[0005] Each conveyor accessory can be uniquely tagged so that the non-magnetic tracking system can distinguish between each of the plurality of conveyor accessories. The conveyor accessories can be reconfigured (e.g., moved around) in the environment of the magnetic tracking system to improve the quality (e.g., accuracy) of the position determination of the tracked object by the magnetic tracking system.

[0006] The technology described herein includes one or more of the following advantages. A transmitter accessory can be placed very close to an area of ​​interest in the environment of a magnetic tracking system, which area of ​​interest can vary for different applications of the magnetic tracking system. For example, the transmitter accessory can include a patch that is attached to a patient during endoscopic surgery. The patch can be moved / rearranged during surgery to keep the patch close to the surgical area of ​​the patient. This can be described as reducing or eliminating the distance between the transmitter accessory and the area of ​​interest. The proximity of the transmitter accessory to the area of ​​interest reduces distortion caused by metal objects in the environment, such as metal operating tables, non-surgical equipment, and the like. For example, the transmitter accessory can be placed along a catheter path in a patient's body so that magnetic tracking of the catheter is improved.

[0007] The transmitter accessory can also be rearranged to be strategically placed for a specific application. For example, if an x-ray image of a patient is taken, the patch can be temporarily removed for the imaging procedure and reapplied after the imaging is completed without requiring recalibration of the magnetic tracking system for continued use.

[0008] These methods reduce or eliminate the need to perform compensation for distortions encountered in typical environments for each situation where the environment of the system varies.

[0009] In one aspect, a magnetic tracking system includes a plurality of transmitter accessories. At least one transmitter accessory includes: a transmitter coil configured to generate a magnetic signal of the transmitter accessory, the magnetic signal indicating an object pose of the tracked object with respect to the transmitter accessory; based on a marker that visually identifies a pose of the transmitter accessory with respect to a camera device. The camera device is configured to capture at least one image of the plurality of transmitter accessories, the image including a representation of the marker on at least one of the transmitter accessories. The computing device is configured to perform operations including: determining a pose of at least one of the transmitter accessories in the image based on an image including a representation of the marker on at least one transmitter accessory; receiving each magnetic signal from the transmitter accessory; determining an object pose of the tracked object in the environment based on each magnetic signal and a pose associated with each transmitter accessory; and outputting a representation of the object pose.

[0010] In some embodiments, at least one of the plurality of transporter accessories is configured to move from a first location in the environment to a second location in the environment during operation of the magnetic tracking system, and wherein the computing device is configured to update a posture associated with the transporter accessory.

[0011] In some embodiments, the indicia comprises an icon. The indicia of the transmitter accessory comprises an outer shape of the transmitter accessory, the outer shape being different from other outer shapes of other transmitter accessories in the plurality of transmitter accessories. In some embodiments, the indicia comprises an infrared reflector, and wherein the camera device comprises an infrared light source.

[0012] In some embodiments, at least one of the plurality of transmitter accessories includes: a memory configured to store calibration data associated with the transmitter accessory; a processing device configured to control transmission of magnetic signals from the transmitter accessory; a communication interface for sending data and receiving data from the computing device or other transmitter accessories in the plurality of transmitter accessories; and a power supply configured to provide power to the memory, the processing device, and the communication interface. The memory may be configured to store calibration data associated with a receiver accessory.

[0013] In some embodiments, at least one of the plurality of transmitter accessories is configured to wirelessly communicate with the computing device. In some embodiments, at least one of the plurality of transmitter accessories includes an adhesive configured to removably attach the transmitter accessory to another surface in the environment.

[0014] In some embodiments, the tracked object includes one of a catheter, an endoscope, or a surgical instrument.

[0015] In some embodiments, the computing device is configured to control the plurality of transmitter accessories to generate magnetic signals. Controlling the plurality of transmitter accessories may include performing time segment multiplexing on each transmitter accessory, the time segment multiplexing causing each of the plurality of transmitter accessories to sequentially transmit the magnetic signals at different times. In some embodiments, controlling the plurality of transmitter accessories includes performing frequency multiplexing on each transmitter accessory, the frequency multiplexing being configured to cause each of the plurality of transmitters to transmit magnetic signals at different frequency values.

[0016] In some embodiments, the plurality of transmitter accessories are connected to the computing device in parallel. In some embodiments, the plurality of transmitter accessories are connected to the computing device in sequence. In some embodiments, at least one transmitter accessory of the plurality of transmitter accessories is modular, wherein the computing device is configured to update a tracking algorithm in response to detecting that the modular transmitter accessory has been removed. In some embodiments, the magnetic tracking system includes a receiver accessory configured to measure magnetic signals from one or more of the transmitter accessories, the receiver accessory including a receiver marker that visually identifies a posture of the receiver accessory with respect to the camera device.

[0017] In some implementations, the computing device is configured to determine a distortion of the magnetic signal based on a first pose associated with the receiver accessory and a second pose associated with a transmitter accessory of the plurality of transmitter accessories.

[0018] In one aspect, a transmitting coil is configured to generate a magnetic signal in response to receiving an electric current; includes a first surface of at least one marker configured to identify a posture of the transmitter accessory relative to a camera device; and is configured to be removably attached to a second surface of another object.

[0019] In some embodiments, the transmitter accessory includes a memory configured to store calibration data associated with the transmitter accessory; a processing device configured to control the transmission of magnetic signals from the transmitter accessory; a communication interface for sending data to and receiving data from a remote device; and a power supply configured to provide power to the memory, the processing device, and the communication interface. In some embodiments, the communication interface is configured to communicate wirelessly with the remote device.

[0020] In some embodiments, the power source is rechargeable. In some embodiments, the marker comprises one of an ArUco pattern, a ChArUco pattern, an infrared reflector, a light source, an ultrasound source, a radio signal source, and an external shape of the transmitter accessory.

[0021] The details of one or more embodiments of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the subject matter will be apparent from the description, drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1A-1B A block diagram of an example of a magnetic tracking system including multiple reconfigurable conveyor accessories is shown.

[0023] Figure 2A Shows Figure 1A-1B Different views of an example conveyor assembly from among multiple conveyor assemblies of FIG.

[0024] Figure 2B Shows Figure 1A-1B Different views of an example receiver assembly for a magnetic tracking system.

[0025] Figure 3A-3B A block diagram of an example transmitter assembly is shown.

[0026] Figure 3C-3D A block diagram of an example receiver assembly is shown.

[0027] Figure 4 A block diagram of an example transmitter array with various transmitter accessories is shown.

[0028] Figure 5 A block diagram of an example magnetic tracking system including different types of conveyor accessories is shown.

[0029] Figure 6 It is used to utilize Figure 1A-5 A flow chart of the process of performing magnetic tracking for a magnetic tracking system and conveyor accessories.

[0030] Figure 7 is a block diagram of an example computer system.

[0031] Like reference numbers in the various drawings indicate like elements. DETAILED DESCRIPTION

[0032] Electromagnetic tracking (EMT) systems (also referred to as magnetic tracking systems) can be used to track objects (e.g., tracked objects) in various environments such as medical facilities. For example, in a surgical facility, an EMT system can be used to track medical equipment (e.g., surgical tools) used for one or more purposes (e.g., endoscopic surgery), thereby allowing the three-dimensional position (e.g., location) and orientation of the object to be known by a medical professional (e.g., surgeon) during a medical procedure. Typically, the magnetic tracking system 100 is configured to track an object within the body to assist a medical professional in performing an operation performed by the medical professional.

[0033] The magnetic tracking system described herein includes a plurality of transmitter accessories. The magnetic tracking system is configured to determine the location of one or more objects about the transmitter accessory, such as by detecting a magnetic signal emitted by one or more of the plurality of transmitter accessories. The transmitter accessories are arranged in different positions / orientations with respect to the receiver of the magnetic tracking system. The magnetic tracking system determines the location of the transmitter accessory about the transmitter by one or more non-magnetic means, such as by visual means, ultrasound, radio signals, etc. Once the location of the transmitter assembly is known, the magnetic tracking system can determine the location and orientation of those objects by tracking their receivers. This can be described as tracking the object (e.g., the tracked object). Relative to the determination of the location and orientation of the object according to the transmitter signal arranged farther away, when the transmitter accessory 106 is placed relatively close to the tracked object (e.g., a few inches away), a more accurate determination result of the location and orientation (e.g., posture) of the object can be determined. This is partly because the distortion caused by the environment of the magnetic tracking system can be reduced or eliminated by arranging the transmitter accessory close to the tracked object.

[0034] Steering Figure 1A, an example magnetic tracking system 100 is shown. The magnetic tracking system 100 includes a computing device 102, a user interface 104, an amplifier 112, a receiver 108, a camera device 110, and one or more transmitter accessories 106.

[0035] The magnetic tracking system 100 is configured to track the position(s) and orientation(s) of one or more tracked objects (not shown) within the environment of the magnetic tracking system 100. In a medical context, the tracked object typically includes a medical device or a portion of a medical device. For example, the magnetic tracking system 100 can be used to track objects such as surgical instruments, probes, endoscopes, catheters, etc. while they are inside the human body. The tracked object includes a receiver that senses signals from one or more of the transmitter accessories 106. As described in more detail later, the magnetic tracking system 100 can determine the position of the receiver of the tracked object based on these signals.

[0036] The magnetic tracking system 100 is configured to transmit a magnetic signal (e.g., a magnetic field) from each of a plurality of transmitter accessories 106. The receiver 108 is configured to measure the magnetic field and send the measured signal to the computing device 102. In some embodiments, an amplifier 112 is included to amplify the signal measured by the receiver 108. The amplifier 112 generally has a positive gain and is configured to amplify any signal received from the receiver 108 so that the computing device 102 can receive the amplified signal as an input. The receiver 108 may include one or more elements, such as a magnetometer, a coil, etc., for measuring the magnetic signal emitted by each of the transmitter accessories 106. In order to perform tracking of the tracked object, the computing device 102 uses the measurement of the field from the transmitter accessories 106 to calculate the position and orientation of the receiver 108. The position and orientation of the transmitter accessories 106 are known by observing the transmitter accessories 106 using a camera 110 or equivalent.

[0037] Each of the transmitter accessories 106 is configured to emit a magnetic signal. A transmitter accessory such as the transmitter accessory 114 includes a transmission element, such as a transmitter coil 116, configured to generate a magnetic signal. Although the transmitter accessories 106 are described collectively, each of the transmitter accessories can be slightly different (or even unique) from one or more other transmitter accessories in the plurality of transmitter accessories. For example, each of the transmitter accessories 106 can be configured to transmit the magnetic signal using a different modulation frequency. In some embodiments, each coil 116 has slightly different magnetic properties. The computing device 102 can store information characterizing the magnetic properties of each of the transmitter accessories 106.

[0038] During operation of the magnetic tracking system 100, each of the transmitter accessories 106 is configured to emit a magnetic signal that can be measured by the receiver 108. The signal from each of the transmitter accessories 106 can be distinguished from other transmitter accessories in the plurality of transmitter accessories. As previously mentioned, this can be achieved by having each transmitter accessory include unique magnetic properties. In some embodiments, each of the transmitter accessories 106 is configured to emit magnetic signals at different times known to the computing device 102. In some embodiments, each of the transmitter accessories 106 is configured to emit magnetic signals at different frequencies known to the computing device 102. Control of the transmitter accessories 106 is described subsequently.

[0039] Each of the transmitter accessories 106 is configured to be identifiable by non-magnetic means to determine the position and orientation of each of the transmitter accessories. The non-magnetic means may include one or more of optical means, ultrasonic means, radio means, etc. Typically, each transmitter accessory includes one or more optical markers 118, such as fiducial markers. The computing device 102 is configured to recognize the marker, distinguish the marker from other markers, and determine the position and orientation of the marker (and therefore the position and orientation of the transmitter accessory) based on the image of the marker.

[0040] The camera 110 is positioned to view the transmitter accessory 106 and provide an image of the transmitter accessory to the computing device 102. The computing device 102 receives the image and determines the position and orientation of each of the transmitter accessories 106 based on the image. The camera 110 is positioned to view the transmitter accessories 106, wherever they are arranged for a given application. For example, in a medical scenario, the camera 110 is placed above the patient and the transmitter 106 is placed on and around the patient. The camera 110 is configured to capture images of the patient and the transmitter accessories 106 on and around the patient to determine the position and orientation of the transmitter accessories with respect to the receiver 108.

[0041] In some embodiments, the camera 110 may be a stereo camera including two cameras such as cameras 110a and 110b that are displaced from each other. The cameras 110a, 110b are configured to capture images from different angles with respect to the conveyor assembly 106. The images from the stereo cameras 110a and 110b may be used to determine not only the planar “x, y” position data and the rotation angle of the conveyor assembly 106, but also the depth “z” position of the conveyor assembly 106 and the roll and pitch of each of the conveyor assemblies 106 with respect to the cameras 110a and 110b.

[0042] Data representing the relative position and orientation of the transmitter accessory 106 is used by the computing device 102 to determine how to interpret the magnetic signal received from the receiver 108. The magnetic signal indicates the position and orientation of the tracked device relative to the transmitter accessory 106. To determine the absolute position and orientation of the tracked device, the position and orientation of the transmitter accessory 106 having a known position and orientation with respect to the patient is determined.

[0043] The receiver 108 is configured to measure the magnetic signal transmitted by the transmitter accessory 106 to determine the position and orientation of the tracked object with respect to the transmitter accessory. The position of the tracked object can be measured relative to any global reference point such as the receiver 108. The computing device 102 is configured to convert the measured magnetic signal into position and orientation data. In some embodiments, the position data can be expressed as a position vector of position coordinates (e.g., x, y, z coordinates). In this example, the receiver 108 uses a Cartesian coordinate system (with x, y, and z coordinates) to represent positioning in space; however, other types of coordinate systems (e.g., cylinders, spheres, etc.) can be used.

[0044] The orientation of a tracked object refers to the direction the tracked device is facing with respect to a global reference point (e.g., receiver 108), and can be similarly expressed using a coordinate system and represented, for example, as orientation coordinates (e.g., azimuth (ψ), altitude (θ) and roll (θ)). The transmitter accessories 106 operate as up to six degrees of freedom (6DoF) measurement systems that are configured to allow measurement of position and orientation information related to forward / backward position, up / down position, left / right position, azimuth, altitude, and roll. For example, if the receiver 108 includes a single receive coil, a minimum set of at least five transmitter accessories 106 can provide five degrees of freedom (e.g., no roll). In one example, if the receiver 108 includes at least two receive coils, a minimum set of at least six transmitter accessories 106 can provide data sufficient for the six degrees of freedom to be determined. Additional transmitter accessories can be added to the plurality of transmitter accessories 106 to improve tracking accuracy or allow for larger tracking volumes.

[0045] The computing device 102 includes one or more processors and is configured to receive position data, orientation data, and motion data measured by the camera 110 of the transmitter accessory 106. The computing device 102 receives magnetic signals from the receiver 108 and converts the magnetic signals into position data and orientation data for the receiver 108. The computing device 102 may include input ports and output ports to send and receive both analog data and digital data. The computing device 102 may include a waveform generator (not shown) for driving the transmitter accessory 106. Aspects and examples of the computing device 102 are further described with respect to Figure 7 Give a description.

[0046] Computing device 102 is configured to determine one or both of the position and orientation of the tracked device based on the magnetic signal received at receiver 108 from transmitter accessory 106 and based on image data from camera 110. Computing device 102 may distinguish between the position data and the orientation data using a device identifier that specifies the tracked object, such as for situations where more than one object is being tracked.

[0047] The computing device 102 may include circuitry for driving the transmitter accessories 106 and controlling the operation of the transmitter accessories 106. For example, the computing device 102 may include a controller configured to control each of the transmitter accessories 106. The transmitter accessories 106 may be configured to transmit magnetic signals at different times or frequencies in a measurement cycle. For example, the computing device 102 may be configured to control each of the transmitter accessories 106 to transmit magnetic signals at specific times in the measurement cycle, transmit magnetic signals in a specific order, and so on, to cycle through each of the transmitter accessories 106. The receiver 108 measures each of the magnetic signals. If a timing mechanism is used, the computing device 102 may associate the received magnetic signal with a specific transmitter accessory based on when the computing device 102 receives the magnetic signal from the receiver 108. The controller may control the transmitter accessories 106 using time segment multiplexing, frequency multiplexing, and the like.

[0048] The transmitter accessories 106 can be individually calibrated. In some embodiments, each transmitter accessory includes one or more properties that are different from other transmitter accessories in the plurality of transmitter accessories. For example, each of the transmitter accessories 106 can be calibrated using modeling parameters, magnetic domain mapping from magnetic signals, spherical harmonics, closed form solutions, etc. The calibration data can be stored by the computing device 102. The calibration data for the transmitter accessories can be stored locally on the local storage with the corresponding transmitter accessory. In one aspect, the calibration data can be sent (e.g., wired or wirelessly) to the computing device 102 to help the computing device 102 determine the position and orientation of the transmitter accessory. As previously mentioned, each of the transmitter accessories 106 can be configured to operate at different frequencies from each other, turn on at different times, and so on.

[0049] Each of the transmitter accessories 106 is configured to be modular. For example, more transmitter accessories 106 can be added to or removed from the plurality of transmitter accessories 106 for different applications. A control algorithm is updated accordingly (e.g., automatically) for the computing device 102 based on a determination of how many transmitter accessories are included in the plurality of transmitter accessories 106. Although a single transmitter accessory can provide some data about the tracked device, the magnetic tracking system 100 typically includes at least 5 transmitter accessories to ensure that five degrees of freedom measurements can be made and includes at least 6 transmitter accessories to ensure that six degrees of freedom measurements can be made.

[0050] Computing device 102 may be configured to determine the position and orientation of the tracked object in a variety of ways. For example, a least squares solution may be used to determine the position and orientation of receiver 108 with respect to transmitter accessory 106. In another example, a Kalman filter or one or more other digital methods may be used to determine the position and orientation of receiver 108 with respect to transmitter accessory 106.

[0051] As is known in the art, the reverse configuration of the previously described magnetic tracking system 100 can be used to track the tracked object. In this example, multiple receiver coils with optical tracking can be paired with a miniaturized transmitter accessory. The transmitter accessory is tracked using magnetic signals received at the multiple receivers.

[0052] The user interface 104 may include a display for reporting the position and orientation of the tracked object to a user of the magnetic tracking system 100. The position and orientation reported to the user may be used to assist the user in one or more applications, such as performing a medical procedure. For example, the user interface may report the position and orientation as a visual representation of the tracked object as a portion of the magnetic tracking system 100, report the coordinates of the tracked object, superimpose the tracked object in an image captured by the camera 110, and the like.

[0053] The user interface 104 may be configured to control the operation of the transmitter accessories 106. The user interface 104 may include one or more controls (software controls, hardware controls, etc.). The controls may be configured to enable a user to turn the transmitter accessories 106 on or off, change the operating frequency of one or more of the transmitter accessories, cause the transmitter accessories to upload calibration data, and the like.

[0054] The computing device 102, the transmitter accessory 106, the camera 110, the amplifier 112, and the user interface 104 can communicate with each other via a wired or wireless connection. For example, the transmitter accessory 106 can be wired into a port of the computing device 102. In such a configuration, the computing device 102 can provide a power signal to drive each transmitter accessory 106, and the transmitter accessories can each include passive electronic devices. In another example, each of the transmitter accessories 106 can be equipped with a data transceiver that is configured to wirelessly transmit data (e.g., calibration information) to the computing device and receive data (e.g., control signals) from the computing device 102.

[0055] The transmitter accessories 106 can be re-deployed during use of the magnetically operated system 100, and the new position and orientation of each transmitter accessory can be determined by the computing device 102 using information from the camera 110. For example, while a tracked object (e.g., a catheter) is moved around in an environment (e.g., within a patient's body), the transmitter accessories 106 can be moved during a surgical procedure to ensure that one or more of the transmitter accessories are within inches of the tracked object. Thus, the transmitter accessories 106 can be reconfigured without requiring recalibration of the magnetic tracking system 100.

[0056] In some embodiments, the transmitter accessory 106 comprises an adhesive patch that can be attached to one or more surfaces of the environment of the magnetic tracking system 100. For example, the transmitter accessory 106 can be attached to the subject of a medical operation (e.g., a patient). For example, as an endoscope navigates inside the patient's body, the transmitter accessory 106 can be unstuck from a first position and moved to a second position that is proximate to (e.g., within 2-3 inches) the path of the endoscope. In some embodiments, the transmitter accessory 106 can be placed directly on the patient's skin above the surgical area. If imaging of the surgical area is required, the patch including the transmitter accessory 106 can be removed, the image captured, and the patch rearranged without recalibrating the magnetic tracking system 100.

[0057] Steering Figure 1B, shows an example of a magnetic tracking system 100 that includes a reconfigurable receiver accessory 120 in addition to a reconfigurable transmitter accessory 106. The receiver accessory 120 is configured to detect signals emitted by the transmitter accessory 106 in a manner similar to the receiver 108 used to track the tracked object. The location of the receiver accessory 120 (or multiple receiver accessories 120) on or near the patient can enable the magnetic tracking system 100 to determine the magnetic field distortion of the magnetic field emitted by the transmitter accessory 106. The (multiple) magnetic fields measured at one or more locations on or near the patient can be compared with the (multiple) optical positions and (multiple) orientations of the receiver accessory 120 to estimate the distortion of the magnetic field near the tracked object. Both the position and orientation of the transceiver transmitting the signal and the position of the receiver can be optically measured from the image of the camera 110. As a result, the computing device 102 can calculate a compensation measure (e.g., an error value) for each transmitter accessory. A magnetic field distortion map can be generated for the system 100 to improve the accuracy of the position estimate of the tracked object. In some embodiments, signals generated by transmitter assemblies 106 that are too close to receiver assemblies 120 (e.g., within 2 inches, within 5 inches, within 10 inches, etc.) may be ignored or filtered for purposes of determining distortion because these signals may saturate receiver 120.

[0058] Similar to receiver 108, receiver accessory 120 includes a receiving coil 128. Receiver accessory 120 may include electronics for processing received signals, such as amplifier 124. Similar to transmitter accessory 106, receiver accessory 120 includes optical indicia 126, which includes an icon, logo, or other content that can be optically distinguished in an image captured by camera 110. Computing device 102 recognizes receiver accessory 120 in the image of camera 110. Computing device 102 is configured to determine the position and orientation of receiver accessory 120 based on the indicia, shape, or other optical properties of receiver accessory 120 in a manner similar to transmitter accessory 106. Receiver accessory 120 may be wired or wireless. Receiver 120 may include additional electronics, such as a battery, memory, data transmitter, and the like.

[0059] The receiver 120 can measure the magnetic field signal emitted by each transmitter assembly 106. Figure 1B, but in some embodiments, the receiver assembly 120 may include one or more other sensing devices, such as a magnetometer, a gravity gradiometer, etc. on an integrated circuit. In some embodiments, multiple coils 128 may be included on each receiver assembly 120. Each sensor coil may have known magnetic properties, or the system 100 may be calibrated to reduce sensor-specific errors. For example, the calibration data may be stored in a memory (e.g., Figure 3C-3D The received signal may be stored locally in each receiver 120 (e.g., in the memory 308). Figure 3C-3D The processed signal may be processed locally by the processing device 304 and sent to the computing device 102.

[0060] In some embodiments, multiple transmitter accessories 106 and receiver accessories 120 can be connected together to form a larger accessory. For example, a rigid flex accessory or an interconnect / daisy chain configuration can be used. For example, each of the transmitter accessories 106 and receiver accessories 120 can be connected wired or wirelessly as an array of additional transmitters and / or receivers of the magnetic tracking system 100. In some embodiments, transmitters and receivers can coexist on a single accessory (e.g., a single accessory 106 or 120). In such a configuration, the transmitter on the accessory can be deactivated while the receiver is active to avoid saturation of the receiver.

[0061] The combination of the receiver accessory 120 and the transmitter accessory 106 can act as a distortion indicator or distortion mapping system for the environment. The magnetic tracking system 100 can use the difference between the optical determination of the optical attitude of each accessory determined and the EM determination of the attitude as an indication of the distortion present in the environment. The magnetic tracking system 100 can therefore perform distortion compensation. For example, data collected by the external receiver accessory 120, including magnetic field measurements and attitude, distortion data, optical data (real), and gradient data (estimated by differences in the field as the sensor moves), can be used to correct for distortion. The distortion can be modeled using a physical model. These models can include curve fitting (e.g., for magnetic signals and for attitude solution), splines, trigonometric calculations, radial basis functions, and the use of machine learning methods.

[0062] The receiver accessory 120 can be placed where needed during operation and easily moved / adjusted during operation. For example, the receiver accessory 120 can be moved during operation to minimize interference with the x-rays. The receiver accessory 120 can be arranged along the path of the catheter / guidewire so as to have continuous distortion indication and / or compensation on the tracking volume. The receiver accessory is placed on the patient's body in close proximity to the working tracking volume. Similar to the transmitter accessory 106, the receiver accessory 120 can be rechargeable (wired or wireless) and / or disposable.

[0063] The receiver of the receiver assembly 120 may be associated with a memory configured to store calibration data for the receiver similar to the calibration data for the transmitter. The calibration data is updated based on the determined distortions in the environment due to hardware transformations of each receiver, etc.

[0064] Receiver accessory 120 can be positioned on or near the patient for tracking the tracked object. In some embodiments, multiple receiver accessories including receiver accessory 120 can be used. As described above, depending on how many receiver accessories and transmitter accessories are used in the magnetic tracking system, five or six degrees of freedom (DoF) can be achieved for tracking system 100. Figure 2B and Figure 3C-3D The receiver assembly 120 is described in greater detail.

[0065] Steering Figure 2A , shows a conveyor accessory 200 (e.g., Figure 1A-1B 1. The transmitter accessory 200 is an example of a transmitter accessory 106 of the present invention. The transmitter accessory 200 is configured to be simple, low-cost and modular. The transmitter accessory 200 includes a first side 202 and a second side 204. In some embodiments, an adhesive patch 206 can be attached to one side (such as the first side 202) to form a stack 212. For different applications of the magnetic tracking system 100, the first side 202 is generally the bottom side facing away from the camera 110. The second side 204 is generally the top side that can be observed in the image captured by the camera 110.

[0066] The first side 202 of the transmitter accessory 200 may include a bottom surface of the transmitter accessory. The first side 202 of the transmitter accessory 200 includes a transmitter coil 210 (which is substantially similar to the transmitter coil 210 described above). Figure 1A-1B Coil 210 may emit a magnetic signal that is received by a receiver of magnetic tracking system 100 (eg, receiver 108 ).

[0067] The second side 204 of the transmitter accessory 200 may include a top surface of the transmitter accessory that is exposed to the camera 110 of the magnetic tracking system 100. The second surface 204 typically includes one or more indicia, such as icons 208a, 208b, and 208c (collectively referred to as icons 208). The icons 208 can each be different from each other, allowing the computing device 102 to distinguish between the icons. The position of the icons 208 relative to each other indicates to the computing device 102 how the transmitter device 200 is located and oriented relative to the camera 110, receiver 108, or other portion of the magnetic tracking system 100. For example, if icon 208b appears in a positive direction along the y-axis with respect to icon 208c, the computing device can determine that the transmitter accessory 200 is rotated at a particular rotation angle (e.g., rotated about the plane of the camera 110). Alternatively, as is known in the art, computer vision or machine learning methods can be used to track the transmitter accessory 200. The icon 208 may be selected from a library of icons, wherein the computing device 102 is configured to identify and assign icons in the library to different ones of the plurality of transmitter accessories. For example, the computing device 102 may identify a particular transmitter accessory 200 based on which icon 208 is on the transmitter accessory. The computing device 102 associates the received magnetic signal with the transmitter accessory 200 to assist in position and orientation calculations. In other words, the computing device 102 uses the icon 208 to obtain which transmitter accessory 200 is associated with which magnetic signal, even after the transmitter accessory 106 is reconfigured. The computing device 102 may then determine an updated position and orientation of the transmitter accessory 106 and, therefore, the tracked object.

[0068] Camera device 110 may include a stereo camera that provides distance information to computing device 102. Computing device 102 may use this distance information (determined at computing device 110 or calculated at computing device 102) to determine the position of conveyor accessory 200 in three dimensions. Camera device 110 may include a single camera that may determine distances, such as distance D1 between icons 208a and 208b, and distance D2 between icons 208b and 208c, based on the use of multiple icons 208 and their known geometry.

[0069] The transmitter accessory 200 includes icons 208a, 208b and 208c for determining the posture of the transmitter accessory 200. The icon 208 is generally configured to be recognized for computer vision recognition. The icon may include any image, such as a barcode, QR code, symbol, etc. In the example of the transmitter accessory 200, the icon 208 is a pixelated symbol. Although three icons are included in this example, additional icons may be added to determine the posture. In addition to being an icon, the transmitter accessory 200 may also include other means of marking the transmitter accessory 200. For example, the logo may include a reflector configured for infrared excitation.

[0070] The transmitter coil 210 is configured to generate a magnetic signal that is received by the receiver 108. The coil 210 can emit a signal (e.g., a magnetic field) that is unique to a particular transmitter accessory 200. For example, the transmitter accessory 200 can modulate the magnetic signal using a specific frequency. The coil 210 can be a single-turn or multi-turn coil. The coil 210 can include any geometric structure that is capable of generating a magnetic field when an electric current is provided. The coil 210 can be part of the circuitry of the transmitter accessory 200 (e.g., a printed circuit board (PCB), or the coil can be separately attached to the transmitter accessory).

[0071] The transmitter accessory 200 may include a layered stack 212, such as a first side 202 and a second side 204, which may form a first layer and a second layer, respectively. The transmitter accessory 200 may include an adhesive layer 206 applied to a first side (e.g., a coil side) of the transmitter accessory 200. The adhesive layer is configured to adhere the transmitter accessory 200 to another surface such as the patient's skin. The surface is not required to be flat or regular. The adhesive layer 206 may include an adhesive, glue, a suction cup or other sticky surface. The adhesive layer 206 is typically configured to be removable and repeatedly reapplied to the surface. The adhesive layer 206 does not obscure the second side 204 including the icon 208.

[0072] The transmitter accessory 200 may not include active circuitry. The coil 210 may be driven from a remote source, such as a waveform generator of the computing device 102. The transmitter accessory 200 may be configured to be plugged into the computing device 102 (or another device) to drive a magnetic signal. In some embodiments, the transmitter accessory 200 may be configured to be connected to one or more other transmitter accessories, such as in a daisy-chain manner. In another example, the transmitter accessory 200 may be connected in parallel with one or more other transmitter accessories.

[0073] Steering Figure 2B , showing a receiver assembly 220 (e.g., Figure 1B 120). The top view of the receiver assembly 220 shows the upper surface 230 of the receiver assembly. Figure 2A The transmitter accessory 200 of the embodiment of the present invention, the receiver accessory 220 may include an optical marker 226 to distinguish a specific receiver accessory from other receiver accessories and / or transmitter accessories. The receiver accessory 220 may include one or more receiving sensors, such as coils L1, L2, and L3. More coils can increase the number of degrees of freedom of measurement.

[0074] A perspective view of a receiver assembly 220 is shown, which includes layers 224 and 230. Layer 224 can be a backing layer configured to be adhered to another surface such as an operating table or a patient. Layer 230 includes indicia 226 and receiver 222. In some embodiments, receiver assembly 220 does not include active circuitry. However, as described later with respect to Figure 1B and 3C -3D, the receiver assembly 220 may include active circuitry.

[0075] Steering Figure 3A-3B , shows a block diagram of an example transmitter assembly. The block diagram shows an example of a transmitter assembly that may be included in Figure 1A-2A The electronic components in the transmitter assembly 106 described in.

[0076] exist Figure 3A , the electronics of a transmitter accessory 300 are shown. The electronics of the transmitter accessory may include active electronics. For example, the transmitter accessory may include its own processing device 304, waveform generator 306, memory 308, and an interface 302 for sending and receiving data, such as through a connector 314. A system on a chip 316 may combine the waveform generator 306, the processing device 304, the interface 302, and the memory 308 into a single module that can be added to or removed from the transmitter accessory. As previously described, in some embodiments, the electronics of the module 316 may be included in the computing device 102.

[0077] Processing device 304 may be configured to control transmitter accessory 300. Processing device 304 may control waveform generator 306, interface 302, and memory 308. Processing device 304 is configured to communicate with computing device 102 and / or other transmitter accessories.

[0078] The memory 308 is configured to store data local to the transmitter accessory 300. For example, the memory 308 may store calibration data associated with the transmitter accessory 300. In some implementations, the memory 308 may store instructions for the processing device 304.

[0079] The waveform generator 306 is configured to drive the coil 210 of the transmitter assembly 300. The frequency and amplitude of the magnetic signal are set from the processing device 304. The waveform generator 306 generates a current configured to cause the desired magnetic signal from the coil 210. The waveform generator 306 sends the generated signal through the amplifier 310, which amplifies the signal and sends the current signal to the coil 210. The coil 210 generates a magnetic signal (e.g., a magnetic field) from the coil. The waveform generator 306 can be configured to generate any waveform required to generate a magnetic signal, such as a sine wave, a pulsed direct current (DC) wave, a quadratic wave, etc.

[0080] The transmitter accessory 300 may include a power source 312. The power source provides local power to the device of module 316 and the amplifier. The power source may include a battery such as a button cell or any other such power source. The power source 3123 may be rechargeable (wired or wireless). In some embodiments, the power source 312 is configured for a single use before the power source is discarded. In some embodiments, assuming that cost is not a constraint, the transmitter accessory 300 is configured for a single use before disposal.

[0081] The interface 302 is configured for wired or wireless communication with other transmitter accessories 106 and computing devices 102. In some implementations, the interface is configured to transmit and receive instructions to and from the transmitter accessory 300.

[0082] Steering Figure 3B , a variation 320 of the transmitter accessory 300 is shown. The transmitter accessory 320 includes an additional connector 318. The connectors 314, 318 can connect the transmitter accessory 320 to other transmitter accessories and the computing device 102 (or other parts of the magnetic tracking system 100). The connector 314 is connected to the connector 318 using a pass-through connection. This allows multiple transmitter accessories 320 to be daisy-chained together. In some embodiments, the electronics of block 316 (which alternatively may not be part of the same chip) can be excluded from the transmitter accessory 320, and common electronics can be used to power, control and drive the magnetic signals of each transmitter accessory 106. Such a configuration is Figure 4 Shown in.

[0083] Steering Figure 3C-3D , a block diagram of an example receiver assembly 330, 340 is shown. The block diagram shows an example of an example receiver assembly 330, 340 that may be included in the Figure 1B and 2B The electronics in the receiver assembly 120 are described. The interface 302, processing device 304, memory 308, amplifier 310, and power supply 312 may all be used in conjunction with the Figure 3A-3B304. The receiver accessories 330, 340 may each include an analog-to-digital converter 332 configured to convert an analog magnetic signal measured by the receiver coil 222 into a digital signal suitable for processing by the processing device 304. As with the transmitter devices 300, 320, the receiver accessories may be connected using connectors 314, 318. In some embodiments, multiple receivers 340 may be connected together (e.g., in a daisy chain configuration). The connectors 314, 318 may allow the receiver accessories 330, 340 to communicate with each other. In addition, the connectors 314, 318 allow for easy connection and disconnection, so that each receiver accessory is modular with other receiver and transmitter accessories and the computing device 102. The accessories 330, 340 may be connected and disconnected for debugging, ease of connection, disposal after use, and other such purposes. In some embodiments, the connected accessories 330, 340 may have a common electronic unit for processing, wireless, and memory capabilities.

[0084] Steering Figure 4 , a block diagram of an example transmitter array 400 is shown having various transmitter assemblies 404, 406, 408, 410, 412, and 414. The transmitter assemblies of array 400 may be controlled, powered, and driven by a single electronics assembly 402. In some embodiments, the electronics assembly is related to Figure 1A-1B A portion of computing device 102 is depicted.

[0085] The array 400 includes a plurality of conveyor assemblies 106 connected together. The conveyor assemblies 106 can be connected together in a daisy chain manner, such as Figure 4 As shown, or connected in parallel to the electronics assembly 402. In some embodiments, the array can be a rigid curved assembly. In some embodiments, the transmitter assembly 106 is wirelessly connected to the array 400.

[0086] Apart from Figure 2A In addition to or in lieu of icon 208, each of teleporter accessories 404, 406, 408, 410, 412, and 414 may have a unique geometry (e.g., shape) to distinguish a particular teleporter accessory from other teleporters in the array. For example, teleporter accessory 404 is a square, teleporter accessory 406 is a circle, teleporter accessory 408 is a triangle, and so on. Camera device 110 and computing device 102 are configured as described above to determine the pose of each of teleporter accessories 404, 406, 408, 410, 412, and 414 in a similar manner.

[0087] Figure 5A block diagram of an example magnetic tracking system 500 including different types of conveyor accessories and camera devices 110 is shown. The magnetic tracking system 500 is similar to the magnetic tracking system 500 described above. Figure 1A-1B The magnetic tracking system 500 is described. Figure 5 In magnetic tracking system 500 , camera 110 is configured to capture images of different types of conveyor accessories, such as conveyor accessory 200 , conveyor accessory 506 , conveyor accessory 508 , and conveyor accessory 510 .

[0088] As previously described, the camera 110 is configured to track all of the plurality of transmitter accessories 106. Images from the camera device 110 can provide information to the computing device 102 to identify which transmitter accessories 106 are part of the active system. The computing device 102 can use the images from the camera device 110 to track the movement of each transmitter accessory 106 and automatically adjust the tracking algorithm. For example, the movement of the transmitter accessory 106 due to the respiration of the patient to which the transmitter accessory is attached can be taken into account. For example, the computing device 102 can determine that the transmitter accessory 106 is moving in a pattern and correct the posture trajectory so that the transmitter accessory 106 is considered to be stationary. Periodic motion, motion that follows a pattern, or motion that is less than a threshold can all be corrected using a prediction and correction algorithm. If too much movement is detected, a warning can be sent to the user interface 104 to notify the user that there may be errors in the tracking of the transmitter accessory 106.

[0089] As previously described, the indicia of each transmitter accessory 200, 506, 508, and 510 may vary so long as they distinguish the corresponding transmitter accessory from other transmitter accessories in the plurality of transmitter accessories. In addition, the transmitter accessories 200, 506, 508, and 510 generally convey sufficient information to determine the pose based on the image or other measurement data of the transmitter accessory. For example, the indicia may include an ArUco or ChArUco pattern 208a, 208b, and 208c. For example, the indicia may include a passive reflector that responds to infrared (IR) excitation from an IR source 504 near the (multiple) camera apertures 110a and 110b. The transmitter accessory 106 may include an active indicia 508 that transmits an optical signal, radio frequency data, an ultrasonic signal, or other pose information. As described with respect to Figure 4 As described, the conveyor accessory 106 itself can be used for pose determination, such as for the conveyor accessory 506 .

[0090] Steering Figure 6 , showing the use of Figure 1A-5 Flowchart of a process 600 for performing magnetic tracking of a magnetic tracking system and a conveyor assembly. Process 600 illustrates a magnetic tracking system (e.g., Figure 1A-1BThe invention relates to a magnetic tracking system 100 of the present invention and how it is configured to determine an object pose of a tracked object in an environment of the magnetic tracking system. The magnetic tracking system 100 includes a plurality of transmitter accessories. Each transmitter accessory includes a transmitter coil configured to generate a magnetic signal for the transmitter accessory. The received magnetic signal indicates an object pose of the tracked object relative to the transmitter accessory. Each transmitter accessory includes a marking that visually identifies the pose of the transmitter accessory relative to a camera device. The camera device is configured to capture at least one image of the plurality of transmitter accessories, including a representation of the marking on each transmitter accessory.

[0091] The camera is configured to capture (602) images of a plurality of conveyor accessories. Process 600 includes, by a computing device (e.g., Figure 1A-1B The computing device 102 of the embodiment of the present invention determines (604) a pose of each transmitter accessory in the image based on the image including a representation of the indicia on each transmitter accessory. The computing device 102 is configured to receive (606) each magnetic signal from the receiver. The computing device 102 is configured to determine (608) an object pose of the tracked object in the environment based on each of the magnetic signals and the pose associated with each transmitter accessory. The computing device is configured to output a representation of the object pose, such as to a user interface.

[0092] In some embodiments, at least one of the plurality of transporter accessories is configured to move from a first location in the environment to a second location in the environment during operation of the magnetic tracking system, and wherein the computing device is configured to update a posture associated with the transporter accessory.

[0093] Typically, the indicia comprises at least three icons at a predetermined distance from each other. The indicia of the transmitter accessory may comprise an outer shape of the transmitter accessory that is different from other outer shapes of other transmitter accessories in the plurality of transmitter accessories. The indicia comprises an infrared reflector, and wherein the camera device comprises an infrared light source.

[0094] Typically, at least one of the plurality of transmitter accessories includes a memory configured to store calibration data associated with the transmitter accessory, a processing device configured to control the transmission of magnetic signals from the transmitter accessory; a communication interface for sending data and receiving data from the computing device or other transmitter accessories in the plurality of transmitter accessories; and a power supply configured to provide power to the memory, the processing device, and the communication interface.

[0095] In some embodiments, at least one of the plurality of transmitter accessories is configured to wirelessly communicate with the computing device. In some embodiments, at least one of the plurality of transmitter accessories includes an adhesive configured to removably attach the transmitter accessory to another surface in the environment. As previously described, the tracked object includes one of a catheter, an endoscope, or a surgical instrument.

[0096] In one aspect, the computing device is configured to control the plurality of transmitter accessories to generate the magnetic signal. Controlling the plurality of transmitter accessories may include performing time segment multiplexing of each transmitter accessory, the time segment multiplexing causing each of the plurality of transmitter accessories to sequentially transmit the magnetic signal at different times. Controlling the plurality of transmitter accessories may include performing frequency multiplexing of each transmitter accessory, the frequency multiplexing being configured to cause each of the plurality of transmitters to transmit the magnetic signal at different frequency values.

[0097] In one aspect, the plurality of transmitter accessories are connected to the computing device in parallel. In one aspect, the plurality of transmitter accessories are connected to the computing device sequentially.

[0098] In some implementations, at least one of the plurality of conveyor accessories is modular.The computing device is configured to update the tracking algorithm in response to detecting that the modular conveyor accessory has been removed.

[0099] The transmitter accessory may include a transmitter coil configured to generate a magnetic signal in response to receiving an electric current; a first surface including at least one mark, the at least one mark configured to identify the posture of the transmitter accessory with respect to the camera device; and a second surface configured to be removably attached to another object. In one aspect, the transmitter accessory includes a memory configured to store calibration data related to the transmitter; a processing device configured to control the transmission of magnetic signals from the transmitter accessory; a communication interface for sending data to a remote device and receiving data; and a power source configured to interface power to the memory, the processing device, and the communication device. In some embodiments, the communication interface is configured to communicate wirelessly with the remote device. In some embodiments, the power source is rechargeable.

[0100] In some embodiments, the marker comprises one of an ArUco pattern, a ChArUco pattern, an infrared reflector, a light source, an ultrasound source, a radio signal source, and an external shape of a transmitter accessory.

[0101] Figure 7 is a block diagram of an example computer system 700 . Figure 1A-1BThe computing device 102 of the present invention can be an example of a computer system 700 described herein. The system 700 may include a processor 710, a memory 720, a storage device 730, and an input / output device 740. Each of the components 710, 720, 730, and 740 may be interconnected, for example, using a system bus 750. The processor 710 is capable of processing instructions for execution within the system 700. The processor 710 may be a single-threaded processor, a multi-threaded processor, or a quantum computer. The processor 710 is capable of processing instructions stored in the memory 720 or on the storage device 730. The processor 710 may perform operations such as causing the EMT system 100 to determine the location and / or orientation of the tracked device 102.

[0102] The memory 720 stores information within the system 700. In some implementations, the memory 720 is a computer-readable medium. The memory 720 may be, for example, a volatile memory unit or a non-volatile memory unit.

[0103] The storage device 730 can provide mass storage for the system 700. In one aspect, the storage device 730 is a non-transient computer readable medium. The storage device 730 may include, for example, a hard disk device, a spectrum device, a solid state hard disk, a flash memory, a magnetic tape, or some other large capacity storage device. The storage device 730 may alternatively be a cloud storage device, for example, a logical storage device including multiple physical storage devices distributed on a network and accessed using the network. In some embodiments, the information stored on the memory 720 is also or additionally stored on the storage device 730.

[0104] The input / output device 740 provides input / output operations for the system 700. In some examples, the input / output device 740 includes one or more network interface devices (e.g., Ethernet card), serial communication devices (e.g., RS-232 10 ports), and / or wireless interface devices (e.g., short-range wireless communication devices, 602.11 cards, 3G wireless modems, or 4G wireless modems). Typically, the input / output device 740 includes a driver device configured to receive input data and send output devices to other input / output devices, such as keyboards, printers, and display devices. In some implementations, mobile computing devices, mobile communication devices, and other devices are used.

[0105] System 700 may include a microcontroller. A microcontroller is a device that contains multiple elements of a computer system in a single electronic package. For example, the single electronic package may contain a processor 710, a memory 720, a storage device 730, and an input / output device 740.

[0106] Although already Figure 7An example computing system is described in the specification, but the subject matter and implementation of the functional operations described above may be implemented in other types of digital electronic circuits, or in computer software, firmware, or hardware, including the structures disclosed in this specification or their structural equivalents, or in a combination of one or more of them. Implementations of the subject matter described in this specification may be implemented as one or more computer program products, i.e., one or more modules of computer program instructions encoded on a tangible computer carrier, such as a computer readable medium, to be executed by a processing system or to control the operation of the processing system. The computer readable medium may be a machine-readable storage device, a machine-readable storage substrate, a memory device, a material composition that affects a machine-readable propagated signal, or a combination of one or more of them.

[0107] The term "computer system" may include all devices, apparatuses, and machines for processing data, including, by way of example, a programmable processor, a computer, or multiple processors or computers. In addition to hardware, a processing system may include code that creates an execution environment for the computer program in question, such as code constituting processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them.

[0108] A computer program (also referred to as a program, software, software application, script, executable logic, or code) can be written in any form of programming language, including compiled or interpreted languages, or declarative or procedural languages, and can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file in a file system. A program can be stored in a portion of a file that stores other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple collaborative files (e.g., files storing one or more modules, subroutines, or code portions). A computer program can be deployed to execute on one computer or on multiple computers located in the same location or distributed across multiple locations and interconnected by a communication network.

[0109] Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile or volatile memory, media and memory devices, including, by way of example, semiconductor memory devices and devices, such as EPROM, EEPROM and flash memory devices; magnetic disks, such as internal hard disks and removable disks or tapes; magnetic optical disks; and CD-ROM and DVD-ROM disks. The processor and memory may be supplemented with or integrated into dedicated logic circuitry. The components of the system may be interconnected by any form or medium of digital data communication, such as a communication network. Examples of communication networks include local area networks ("LANs") and wide area networks ("WANs"), such as the Internet.

[0110] A number of embodiments have been described. However, it will be understood that various modifications may be made without departing from the spirit and scope of the subject matter described herein. Other such embodiments are within the scope of the following claims.

Claims

1. A magnetic tracking system for determining an object pose of a tracked object in an environment of the magnetic tracking system, the magnetic tracking system comprising: A plurality of conveyor accessories, at least one conveyor accessory comprising: a transmit coil configured to generate a magnetic signal of the transmitter accessory, the magnetic signal being indicative of an object pose of a tracked object relative to the transmitter accessory, wherein the transmitter accessory is not attached to the tracked object; and indicia that visually identifies a posture of the transmitter accessory relative to the camera device; wherein the camera device is configured to capture at least one image of the plurality of transmitter accessories, the at least one image comprising a representation of a logo on the at least one transmitter accessory of the plurality of transmitter accessories; and A computing device configured to perform operations including: determining a pose of the at least one of the plurality of conveyor accessories in the image based on the image including the representation of the indicia on each of the plurality of conveyor accessories; receiving each of the magnetic signals from the at least one transmitter assembly of the plurality of transmitter assemblies; determining the object pose of the tracked object in the environment based on each of the magnetic signals and the pose associated with the at least one of the plurality of transmitter accessories; and A representation of the pose of the object is output.

2. The magnetic tracking system according to claim 1, wherein: At least one of the plurality of transporter accessories is configured to move from a first location in the environment to a second location in the environment during operation of the magnetic tracking system, and wherein the computing device is configured to update a pose associated with the transporter accessory.

3. The magnetic tracking system according to claim 1, wherein: The logo includes an icon.

4. The magnetic tracking system of claim 1, wherein: The indicia of a conveyor accessory comprises an outer shape of the conveyor accessory that is different from other outer shapes of other conveyor accessories in the plurality of conveyor accessories.

5. The magnetic tracking system of claim 1, wherein: The marker includes an infrared reflector, and wherein the camera device includes an infrared light source.

6. The magnetic tracking system of claim 1, wherein: At least one of the plurality of conveyor accessories comprises: a memory configured to store calibration data associated with the transmitter assembly; a processing device configured to control transmission of the magnetic signal from the transmitter assembly; a communication interface for sending data to and receiving data from the computing device or other transmitter assemblies of the plurality of transmitter assemblies; and A power supply is configured to provide power to the memory, the processing device, and the communication interface.

7. The magnetic tracking system of claim 1, wherein: At least one transmitter accessory of the plurality of transmitter accessories is configured to communicate wirelessly with the computing device.

8. The magnetic tracking system of claim 1, wherein: At least one conveyor accessory of the plurality of conveyor accessories includes an adhesive configured to removably attach the conveyor accessory to another surface in the environment.

9. The magnetic tracking system of claim 1, wherein: The tracked object is a surgical instrument.

10. The magnetic tracking system of claim 9, wherein: The surgical instrument includes one of a catheter or an endoscope.

11. The magnetic tracking system of claim 1 , wherein: The computing device is configured to control the plurality of transmitter accessories to generate the magnetic signal.

12. The magnetic tracking system of claim 11, wherein: Controlling the plurality of transmitter assemblies includes performing time-segment multiplexing of each of the plurality of transmitter assemblies, the time-segment multiplexing causing each of the plurality of transmitter assemblies to sequentially transmit the magnetic signal at different times.

13. The magnetic tracking system of claim 11, wherein: Controlling the plurality of transmitter assemblies includes performing frequency multiplexing on each of the plurality of transmitter assemblies, the frequency multiplexing configured such that each of the plurality of transmitter assemblies transmits magnetic signals at different frequency values.

14. The magnetic tracking system of claim 1, wherein: The plurality of transmitter assemblies are connected in parallel to the computing device.

15. The magnetic tracking system of claim 1, wherein: The plurality of transmitter assemblies are sequentially connected to the computing device.

16. The magnetic tracking system of claim 1, wherein: At least one of the plurality of conveyor accessories is modular, wherein the computing device is configured to update the tracking algorithm in response to detecting that the modular conveyor accessory has been removed.

17. The magnetic tracking system of claim 1, further comprising a receiver accessory configured to measure the magnetic signal from one or more transmitter accessories of the plurality of transmitter accessories, the receiver accessory comprising a receiver marker that visually identifies a posture of the receiver accessory relative to the camera device.

18. The magnetic tracking system of claim 17, wherein: The computing device is configured to determine a distortion of the magnetic signal based on a first pose associated with the receiver accessory and a second pose associated with a transmitter accessory of the plurality of transmitter accessories.

19. A transmitter assembly for generating a magnetic signal, comprising: a transmitting coil configured to generate a magnetic signal in response to receiving the electric current; a first surface comprising at least one marking configured to identify a pose of the transmitter accessory relative to a camera device; as well as A second surface is configured to be removably attached to another object other than the object to be tracked by the conveyor assembly.

20. The conveyor accessory of claim 19, further comprising: a memory configured to store calibration data associated with the transmitter assembly; a processing device configured to control transmission of the magnetic signal from the transmitter assembly; A communication interface for sending and receiving data to a remote device; and A power source configured to provide power to the memory, the processing device, and the communication interface.

21. The conveyor accessory of claim 20, wherein: The communication interface is configured to communicate wirelessly with the remote device.

22. The conveyor accessory of claim 20, wherein: The power source is rechargeable.

23. The conveyor accessory of claim 19, wherein: The marker comprises one of the following: an ArUco pattern, a ChArUco pattern, an infrared reflector, a light source, an ultrasonic source, a radio signal source, and an external shape of the transmitter accessory.

24. A method for determining an object pose of an object being tracked in the environment of a magnetic tracking system, comprising: acquiring a magnetic signal from each of the one or more transmitter accessories, the magnetic signal indicating an object pose of a tracked object relative to the transmitter accessory, wherein each of the one or more transmitter accessories is not attached to the tracked object; acquiring image data representing indicia on each of the one or more conveyor accessories; determining a pose of each of the one or more conveyor accessories based on the image data representing indicia on each of the one or more conveyor accessories; determining an object pose of a tracked object in the environment based on the magnetic signal of each of the one or more transmitter accessories and the pose associated with each of the corresponding one or more transmitter accessories; and A representation of the object pose of the tracked object is output.

25. The method according to claim 24, wherein: At least one of the one or more transporter accessories is configured to move from a first location in the environment to a second location in the environment during operation of the magnetic tracking system, and wherein the computing device is configured to update a pose associated with the at least one transporter accessory.

26. The method according to claim 24, wherein: The logo includes an icon.

27. The method according to claim 24, wherein: The indicia of a conveyor accessory comprises an outer shape of the conveyor accessory that is different from other outer shapes of other conveyor accessories in a plurality of conveyor accessories.

28. The method of claim 24, wherein: The marker includes an infrared reflector.

29. The method of claim 24, wherein: At least one of the one or more conveyor accessories comprises: a memory configured to store calibration data associated with the transmitter assembly; a processing device configured to control transmission of the magnetic signal from the transmitter assembly; a communication interface for sending data to and receiving data from the computing device or other transmitter assemblies of the plurality of transmitter assemblies; and A power supply is configured to provide power to the memory, the processing device, and the communication interface.

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