阅读说明：本技术 外科手术套管以及用于识别外科手术套管的相关系统和方法 (Surgical cannulas and related systems and methods for identifying surgical cannulas ) 是由 B·R·加伯斯 A·汤普森 J·克鲁姆 于 2015-03-17 设计创作，主要内容包括：本发明涉及外科手术套管以及用于识别外科手术套管的相关系统和方法,公开了一种用于外科手术系统的套管可以包括磁铁,该磁铁位于套管被安装到外科手术系统的位置、有待被外科手术系统感测的位置。磁铁的存在和磁铁的极性中的至少一个在套管的安装位置被感测到,以提供与套管相关的识别信息。示例性实施例进一步包括用于遥操作的外科手术系统的患者侧推车,该患者侧推车包括基座、主立柱以及与主立柱连接的臂。臂可以包括用于接收套管的座架以及用于感测套管中的识别装置的磁铁的读取器,以便接收与安装套管相关的识别信息。(A cannula for a surgical system may include a magnet at a location where the cannula is mounted to the surgical system, a location to be sensed by the surgical system. At least one of the presence of the magnet and the polarity of the magnet is sensed at the installed position of the cannula to provide identification information related to the cannula. Exemplary embodiments further include a patient side cart for a teleoperated surgical system, the patient side cart including a base, a main column, and an arm connected with the main column. The arm may comprise a mount for receiving the cannula and a reader for sensing a magnet of the identification means in the cannula in order to receive identification information relating to the mounting of the cannula.)

1. A cannula for a surgical system, comprising:

a magnet located at a position to be sensed by the surgical system where the cannula is mounted to the surgical system; and is

Wherein at least one of a presence of the magnet and a polarity of the magnet is sensed at a mounting location of the cannula, the at least one of the presence and the polarity indicating identification information associated with the cannula.

2. The cannula of claim 1, further comprising an attachment portion engageable with a portion of a surgical system to mount the cannula to the surgical system, wherein the magnet is located in the attachment portion.

3. The cannula of claim 2, wherein the attachment portion connects an arm of the surgical system at a location where the cannula is mounted to the surgical system.

4. The cannula of claim 1, wherein the polarity of the magnet is a predetermined magnetic pole of the magnet.

5. The cannula of claim 1, wherein the magnet is a samarium cobalt magnet.

6. The cannula of claim 1, wherein the magnet is exposed on a surface of the cannula.

7. The cannula of claim 1, wherein the magnet is covered by a portion of the cannula.

8. The cannula of claim 1, wherein the magnet is covered by a cover portion sealed to the cannula.

9. The cannula of claim 8, wherein the cover portion is made of metal.

10. The cannula of claim 1, further comprising an array of magnet locations, wherein the magnet is located at one of the magnet locations.

Technical Field

Aspects of the present disclosure relate to surgical cannulas and related systems and methods for identifying surgical cannulas.

Background

Remotely controlled surgical instruments, which can include teleoperated surgical instruments as well as manually operated (e.g., laparoscopic, thoracoscopic) surgical instruments, are often used for minimally invasive medical procedures. In a surgical procedure, a surgical instrument is extended through a cannula inserted into a patient's body and remotely manipulated to perform a procedure at a surgical site. For example, in teleoperated surgical systems, the cannula and surgical instruments can be mounted at a manipulator arm of a patient side cart and remotely manipulated via teleoperation at a surgeon console. The cannula may have different configurations useful for various types of surgical procedures. While these different cannula configurations are useful and effective for surgical procedures, further improvements to the cannula and surgical systems using the cannula, including improvements for automatically identifying the cannula, may be desired.

Disclosure of Invention

Exemplary embodiments of the present disclosure may address one or more of the above-described problems and/or may exhibit one or more of the above-described desirable features. Other features and/or advantages may become apparent from the following description.

According to at least one example embodiment, a cannula for a surgical system includes a magnet located at a position to be sensed by the surgical system at a location where the cannula is mounted to the surgical system. At least one of the presence of the magnet and the polarity of the magnet is sensed in the installed position of the cannula to provide identification information related to the cannula.

According to at least one exemplary embodiment, a patient side cart for a teleoperated surgical system includes a base, a main column, and an arm connected to the main column. The arm may comprise a mount for receiving the cannula and a reader for sensing a magnet of the identification device in the cannula to receive identification information relating to the mounting of the cannula.

Additional objects, features and/or advantages will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the disclosure and/or the claims. At least some of these objects and advantages may be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the claims. Rather, the claims and their equivalents should be accorded their full scope and breadth.

Drawings

The disclosure can be understood in light of the following detailed description (taken alone or in combination with the accompanying drawings). The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more exemplary embodiments of the present teachings and together with the description serve to explain certain principles and operations.

Fig. 1 is a perspective view of a patient side cart according to an exemplary embodiment.

Fig. 2 is a side view of a cannula according to an exemplary embodiment.

FIG. 3 is a side view of a cannula having a curved tube according to an exemplary embodiment.

FIG. 4 is a perspective view of a cannula and an arm to which the cannula is connected according to an exemplary embodiment.

Fig. 5 is a bottom perspective view of a cannula including an identification device according to an exemplary embodiment.

Fig. 6 is a partial side cross-sectional view of a cannula attachment portion connected to a patient side cart manipulator arm according to an exemplary embodiment.

FIG. 7 is a bottom perspective view of a cannula with an identification device according to another exemplary embodiment.

Fig. 8 is a top schematic view of an identification appliance according to an exemplary embodiment.

Fig. 9 is a top schematic view of a reader for use with an identification device according to an exemplary embodiment.

FIG. 10 is a top schematic view of a sensor group including four sensors according to an exemplary embodiment.

FIG. 11 is a voltage versus magnetic flux schematic for a Hall effect device according to an exemplary embodiment.

FIG. 12 is a top schematic view of a sensor group including three sensors according to an exemplary embodiment.

FIG. 13 is a top schematic view of a sensor group including two sensors according to an exemplary embodiment.

FIG. 14 is a top schematic view of a sensor group including one sensor, according to an example embodiment.

Fig. 15 is a perspective view of an identification appliance including an orientation magnet according to an exemplary embodiment.

Fig. 16 is a bottom perspective view of a cannula including an array of a plurality of magnet locations according to an exemplary embodiment.

Detailed Description

The description and drawings illustrating exemplary embodiments should not be taken to be limiting. Various mechanical, compositional, structural, electrical, and operational changes may be made without departing from the scope of the description and claims and their equivalents. In some instances, well-known structures and techniques have not been shown or described in detail to avoid obscuring the present disclosure. The same numbers in two or more drawings identify the same or similar elements. Additionally, elements and their associated features described in detail with reference to one embodiment may, in practice, be included in other embodiments not specifically shown or described. For example, if an element is described in detail with reference to one embodiment and not described with reference to the second embodiment, the element may still be said to be included in the second embodiment.

For the purposes of this specification and the appended claims, unless otherwise indicated, all numbers expressing quantities, percentages or proportions, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term "about" to the extent they have not been so modified. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

It is noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" and any singular use of any word include plural referents unless expressly and unequivocally limited to one referent. As used herein, the term "include" and grammatical variations thereof are intended to be non-limiting such that items recited in the list are not exclusive of other similar items that can be substituted or added to the listed items.

Additionally, the terminology of the present description is not intended to limit the present disclosure or claims. For example, spatially relative terms, such as "under," "below," "inferior," "above," "upper," "proximal," "distal," and the like, may be used to describe one element or feature's relationship to another element or feature as illustrated in the orientation of the figures. These spatially relative terms are intended to encompass: in addition to the positions and orientations shown in the figures, different positions (i.e., orientations) and orientations (i.e., rotational placements) of the device in use or operation are also encompassed. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "above" the other elements or features. Thus, the exemplary term "below" can encompass both a position and an orientation above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. The relative proximal and distal directions of the surgical instrument are labeled in the figures.

It may be desirable to provide a cannula identification system and method in which a cannula is automatically detected (e.g., determination of the presence of a cannula) and identified (e.g., determination of the type of cannula). For example, the surgical system may include a sensor that automatically detects identification information about the cannula when the cannula is used with the surgical system (such as when the cannula is attached to a component of the surgical system for use during a surgical procedure). The cannula may include means that allow for various numbers of unique combinations of identification information to be provided such that the identification information includes information about various aspects of the cannula. The device may include identification in a format that is mechanically automatically detected by the reader.

Various exemplary embodiments of the present disclosure contemplate identification devices, systems, and methods for identifying cannulas of a surgical system. The cannula may include a bowl portion forming a proximal end, a tube forming a distal end, and an attachment portion configured to connect to an arm of a patient side cart to connect the cannula to the patient side cart. The cannula may include an identification device that includes identification information about the cannula in a format that is automatically obtained (such as by a reader). According to one example, the identification means is located at the attachment portion. The identification means may comprise a magnet representing the identification information by a predetermined parameter of the magnet. The magnets may be samarium cobalt magnets or other permanent magnet materials known to those of ordinary skill in the art. The identification device may comprise a plurality of magnet locations and a magnet located in at least one of the magnet locations. The identification information may be represented by the presence or absence of a magnet in the magnet position and the polarity of the magnetic field of the magnet. The identification information may include at least one of a length of the tube, a diameter of the tube, a material of the cannula, whether the tube is straight or includes a curved portion, and/or whether the cannula is configured for use with a surgical instrument having an end effector or for use with an imaging instrument.

Various exemplary embodiments of the present disclosure also contemplate a patient side cart of a surgical system that includes a reader for obtaining identification information from an identification device of a cannula. The patient side cart includes a base, a main column, and an arm to which the cannula may be connected. The reader may be located in a patient side cart. The reader includes, for example, at least one sensor configured to detect a magnet, such as, for example, a hall effect device.

The reader may comprise at least one sensor group, wherein each sensor group comprises a plurality of sensors. In one example, each sensor group includes a full polarity sensor to detect the polarity of the magnet in the corresponding magnet position of the identification device. In another example, the sensor groups each include a presence sensor to detect the presence of a magnet in a corresponding magnet position of the identification device, and a polarity sensor to detect a selectively predetermined magnetic pole of the magnet. The sensor groups may each comprise a plurality of presence sensors and two polarity sensors, wherein one polarity sensor detects a north polarity magnetic field and one polarity sensor detects a south polarity magnetic field. The presence sensor may be a full polarity sensor and the polarity sensor may be a single polarity sensor. In another example, the sensor includes a magnetic field direction sensor configured to detect an angular orientation of a magnetic field of a magnet of the identification device.

While the readers of the exemplary embodiments described herein may be described as part of a surgical system (such as, for example, a manipulator arm of a patient side cart), the readers of the exemplary embodiments described herein may also be used as manual devices. For example, the reader is a handheld device that a user quickly identifies various cannulas without using a surgical system. For example, a user may want to identify cannulae before or after a surgical procedure in order to classify cannulae by type.

Referring now to fig. 1, an exemplary embodiment of a patient side cart 100 of a teleoperated surgical system is shown. The teleoperated Surgical System may further include a surgeon console (not shown) for receiving input from a user to control the instruments of the patient side cart 100, and auxiliary control/vision carts (not shown), for example as described in U.S. publication No. US2013/0325033 entitled "Multi-Port Surgical System Architecture" published on 12/5 2013 and U.S. publication No. US 20184 entitled "reduce Axis and grid of free for hard-Constrained Remote Robotic Manipulator" published on 12/5 2013, each of which is incorporated herein by reference in its entirety. Non-limiting exemplary embodiments of teleoperated Surgical systems that may utilize the principles of the present disclosure include da, available from Intuitive Surgical, Inc. of the Senecio, Calif

Si (model IS3000) daSi Surgical System、Single Site da

Surgical System or daXiSurgical System。

The patient side cart 100 includes a base 102, a main column 104, and a main support arm 106 connected to the main column 104. The patient side cart 100 may further comprise a plurality of arms 110, 111, 112, 113, the plurality of arms 110, 111, 112, 113 each being connected to the main arm 106. The arms 110, 111, 112, 113 each include an instrument mounting portion 120 to which an instrument 130 may be mounted, the instrument mounting portion 120 being illustrated as being attached to the arm 110. Portions of the arms 110, 111, 112, 113 may be manipulated during a surgical procedure according to commands provided by a user at a surgeon console. In an exemplary embodiment, the signal(s) or input(s) transmitted from the surgeon console may be transmitted to a control/vision cart that may interpret the input(s) and generate command(s) or output(s) to be transmitted to the patient side cart 100 to cause manipulation of the instrument 130 (only one such instrument is installed in fig. 1) and/or the portion of the arm 110 to which the instrument 130 is coupled at the patient side cart 100.

According to an exemplary embodiment, instrument mounting portion 120 includes an actuation interface fitting 122 and an attachment mount 124, wherein a shaft 132 of instrument 130 extends through attachment mount 124 (and onto a surgical site during a surgical procedure) and a force transmission mechanism 134 of instrument 130 is coupled with actuation interface fitting 122. Accessory mount 124 is configured to hold a cannula (not shown in fig. 1) through which shaft 132 of instrument 130 may extend to a surgical site during a surgical procedure. Actuation interface fitting 122 contains various drivers and other mechanisms that are controlled to respond to input commands at the surgeon's console and transmit forces to force transmission mechanism 134 to actuate instrument 130, as is well known to those skilled in the art.

For ease of viewing, while the exemplary embodiment of fig. 1 shows the instrument 130 attached only to the arm 110, the instrument may be attached to any and each of the arms 110, 111, 112, 113. The instrument 130 may be a surgical instrument having an end effector, or may be an endoscopic imaging instrument or other sensing instrument used during a surgical procedure to provide information (e.g., visualization, electrophysiological activity, pressure, fluid flow, and/or other sensed data) of a remote surgical site. In the exemplary embodiment of fig. 1, a surgical or imaging instrument having an end effector may be attached to any of the arms 110, 111, 112, 113 and used with any of the arms 110, 111, 112, 113. However, the embodiments described herein are not limited to the exemplary embodiment of fig. 1, and various other teleoperated surgical system configurations may be used with the exemplary embodiments described herein.

The cannula may have a number of different configurations useful for various types of surgical procedures. For example, the cannula may have different lengths, diameters, materials, curvatures, and configurations of other parameters based on the type of instrument used. Thus, many different configurations of the bushing are possible, especially when considering the possible combinations of various parameters of the bushing that may vary. In view of this consideration, it would be desirable to provide a system that is capable of automatically identifying different casing types. For example, it may be desirable to provide a teleoperated surgical system that is capable of automatically identifying different cannula types, such as when the cannula is mounted on an arm of a patient side cart. Additionally, it may be desirable for the identification means of the cannula to be durable and to withstand repeated use, including cleaning procedures.

Turning to fig. 2, a side view of an exemplary embodiment of a cannula 300 is shown. Cannula 300 may include an attachment portion 310, a bowl portion 302 forming a proximal end 304 of cannula 300, and a tube 306 extending from bowl portion 302 to a distal end 308 of cannula 300. The present disclosure contemplates a bowl portion having a funnel configuration with a wide opening at one end (e.g., at the proximal end 304) leading to a smaller opening at the end where the bowl portion is connected to the tube portion (e.g., toward the distal end 308). The proximal and distal directions are labeled with respect to the orientation of fig. 2. As in the exemplary embodiment of fig. 2, tube 306 may have a length L and distal end 308 may have a diameter D, each of which may vary depending on the desired application of cannula 300, as is well known to those of ordinary skill in the art. Additionally, as shown in the exemplary embodiment of fig. 2, tube 306 is straight, but the exemplary cannula embodiments described herein are not limited to a straight tube. For example, the sleeve 400 includes an attachment portion 410, a bowl portion 402, and a curved tube 404 (e.g., a tube having a curved longitudinal axis along all or a portion of its length), as shown in the exemplary embodiment of fig. 3.

Cannula 300 may be inserted through an opening in a patient's body to a surgical site. For example, the distal end 308 of the cannula may be inserted through an opening (such as, for example, an incision, natural orifice, or port) to a surgical site. A surgical instrument (such as instrument 160 in the exemplary embodiment of fig. 1) may be inserted through cannula 300 to a surgical site. For example, an instrument may be inserted into the proximal end 304 of the cannula and extend through the bowl portion 302, the tube 306, and the distal end 308 of the cannula 300 to the surgical site.

According to an exemplary embodiment, the cannula 300 may be attached to an accessory mount to connect the cannula to an arm of a patient side cart, such as the accessory mount 124 of the arm 110, 111, 112 or 113 of the patient side cart 100 of the exemplary embodiment of fig. 1. For example, the cannula 300 includes an attachment portion 310 to connect the cannula 300 to an accessory mount of an arm. According to an exemplary embodiment, the attachment portion 310 is, for example, a protrusion configured to be inserted into or retained by an accessory mount of the arm. As shown in the exemplary embodiment of fig. 2, attachment portion 310 is a portion of bowl portion 302 of sleeve 300 or is otherwise connected to bowl portion 302 of sleeve 300.

Turning to fig. 4, an exemplary embodiment of a portion of an arm 520 of a patient side cart and a cannula 500 in an unconnected state is shown. The arm 520 is, for example, one of the arms 110, 111, 112, 113 of the patient side cart 100 of the exemplary embodiment of fig. 1. The sleeve 500 may be configured according to various exemplary embodiments herein and may include, for example, an attachment portion 510, a bowl portion 502 forming a proximal end 504, and a tube portion 506 extending from the bowl portion 502 to a distal end 508. The sleeve 500 may be connected to the arm 520 by inserting the attachment portion 510 into an accessory mount 522 of the arm 520 (such as, for example, the accessory mount 124 in the exemplary embodiment of fig. 1).

According to an exemplary embodiment, the accessory mount 522 of the arm 520 includes a sterile adaptor 530. The sterile adaptor 530 may include a recess 532 into which the attachment portion 510 of the cannula 500 may be inserted for attaching the cannula 500 to the arm 520. Sterile adapter 530 may provide a boundary between a sterile field and a non-sterile field. For example, the sterile adapter 530 is positioned between the cannula 500, at least a portion of which is located in a sterile field during a surgical procedure, and the arm 520, which may be in a non-sterile field during a surgical procedure, thereby maintaining a barrier between the cannula 500 and the arm 520. According to an exemplary embodiment, the surgical drape 534 (a portion of which is schematically indicated in dashed lines in fig. 4) is connected to the sterile adapter 530 to form a barrier between the sterile side 536, at which at least a portion of the cannula 500 is located, and the non-sterile side 538, at which the arm 520 is located.

As discussed above, various parameters of the configuration of the casing may be varied, allowing for various possible combinations of parameters of the casing. Accordingly, it may be desirable for the cannula to include an identification device so that the cannula may be automatically identified by the surgical system, such as when the cannula is connected to the surgical system. The identification means comprises information about the configuration of the cannula, such that the information allows the mechanical reader to automatically obtain the information. For example, the identifying information may include information regarding the length, diameter, and material of the cannula, whether the cannula is straight or curved, whether the cannula is used with a surgical instrument having an end effector or with an imaging instrument, and/or other parameters. Turning to fig. 5, a perspective view of the sleeve 500 of the exemplary embodiment of fig. 4 is shown. According to an exemplary embodiment, the cannula 500 comprises an identification means in the attachment portion 510 of the cannula 500. For example, the identification device is located at the distal portion 512 of the attachment portion 510, but exemplary embodiments according to the present disclosure are not limited to identification devices located at the distal portion 512.

According to an exemplary embodiment, the identification means of the cannula interacts with a reader of the surgical system. For example, when the attachment portion of the cannula is attached to an arm of the surgical system, a reader located in the arm interacts with an identification device in the attachment portion and identification information about the cannula is automatically obtained from the identification device. Thus, when the attachment portion 510 of the cannula 500 is attached to the arm 520 in the exemplary embodiment of fig. 4, a reader located within the arm may obtain identification information about the cannula 500 from an identification device located in the attachment portion 510, such as through the surgical adapter 530.

Fig. 6 depicts a partial cross-sectional view showing the attachment portion 610 attached to the arm 620 of the patient side cart. The attachment portion 610 and the arm 620 may be arranged according to the exemplary embodiment of fig. 4, such as the attachment portion 510 and the arm 520 of the cannula 500. Thus, for simplicity, although the sterile adapter is not shown in the exemplary embodiment of fig. 6, the sterile adapter may be located between the attachment portion 610 and the arm 620, as described above with respect to the sterile adapter 530 and drape 534 of the exemplary embodiment of fig. 4, without altering the principles of operation of the identification device and reader as described below.

As shown in fig. 6, the attachment portion 610 may include an identification device 614 that provides identification information for the cannula. The arm 620 may include a reader 622 for receiving identification information from the identification device 614. According to an exemplary embodiment, the reader 622 includes a sensor 624 for receiving identification information from the identification device 614. Although the reader 622 may include a single sensor, such as, for example, the single sensor 624 for the identification device 614, the example embodiments described herein are not limited to a single sensor for the reader. Rather, according to an exemplary embodiment, the reader 622 includes one, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, fifteen, sixteen, or more sensors 624. For example, as will be discussed below, the reader 622 includes a plurality of sensors in an array. The reader 622 may further include one or more transmission lines 626 to transmit the signal(s) from the reader 622 to the surgical system, such as transmitting a signal including identification information obtained from the cannula.

An identification device according to an exemplary embodiment may provide identification information, such as in a format that is automatically read by a machine in various ways. According to an exemplary embodiment, the identification means comprises a magnet sensed by the reader, wherein a magnetic pole sensed by the reader is used as the identification information. For example, the magnet may be positioned in the sleeve such that a predetermined magnetic pole of the magnet faces the reader. According to an exemplary embodiment, the end of a magnet having a desired polarity (i.e., north or south) may be positioned on the sleeve to face the reader. As shown in the exemplary embodiment of fig. 7, the sleeve 700 includes a magnet 714 as an identification device 714. In fig. 7, the magnet 714 protrudes from a surface 716 of the attachment portion 710 such that when the attachment portion 710 is connected to an arm of a patient side cart, a predetermined pole of the magnet 714 faces a reader, such as the reader 622 in the exemplary embodiment of fig. 6. Although a single magnet 714 is shown protruding from the surface 716 in the exemplary embodiment of fig. 7, the identification device may include multiple magnets 714 protruding from the surface 716. For example, as depicted in the exemplary embodiment of fig. 16, the cannula 1600 may include an attachment portion 1610 having an array 1612 including a plurality of magnet locations 1614 for one or more magnets. Positioning the identification device 714 so as to protrude from the surface 716 may reduce interference between the identification device 714 and the ferrule 700, such as when the ferrule 700 is made of a magnetic metal (e.g., type 17-4 stainless steel). According to an exemplary embodiment, the identification device 714 is positioned such that approximately half of the identification device 714 is embedded within the sleeve 700 and approximately half of the identification device 714 protrudes from the surface 716. However, other locations of the magnets of the identification device are contemplated within the scope of the present disclosure.

In the exemplary embodiment of fig. 7, the identification device 714 is exposed. However, the exemplary embodiments described herein are not limited to exposed identification devices and may instead include identification devices that are not exposed. For example, the identification device 614 is covered, such as by a cover portion 612, as shown in the exemplary embodiment of fig. 6. When the identification device 614 is a magnet, the cover portion 612 may be made of metal. According to an exemplary embodiment, the cover portion 612 is made of a non-magnetic material, such as, for example, austenitic stainless steel. The cover portion 612 may be joined to the attachment portion 610 by, for example, welding, brazing, soldering, adhesives, or other joining methods known to those of ordinary skill in the art. According to an exemplary embodiment, the cover portion 612 is joined to the attachment portion 610 such that the cover portion 612 is sealed (e.g., has a liquid-tight seal) to the attachment portion 610.

The type of magnet used for the identification means can be selected according to various parameters. According to an exemplary embodiment, in a cannula including an array of magnets and a reader including a reader configured to detect each magnet, the magnets may be selected such that the magnetic field strength is sufficient for detection by a particular reader configured and positioned for the purpose of detecting the magnet, but insufficient for detection by another reader configured and positioned for the purpose of detecting a different magnet. Thus, the magnets of the various exemplary embodiments described herein may have a magnetic field strength of, for example, about 17 to about 19 gauss. According to an exemplary embodiment, the magnet may be selected to withstand repeated use in the cannula, including repeated sterilization procedures. The sterilization process may include autoclaving, which may subject the magnet to high temperatures, which may even exceed the curie temperature of the magnet. In view of this consideration, the magnets may be permanent magnets made of samarium cobalt alloy, neodymium alloy, or other permanent magnet iron materials known to those of ordinary skill in the art. An example of a permanent magnet is a samarium cobalt grade 1-5 magnet sold by McMaster-Carr corporation of Princeton, NJ.

As discussed above, the magnet may be used as an identification device to provide identification information for the cannula carrying the magnet. To provide a desired number of variable combinations corresponding to various parameters that may be included in the identification information for uniquely identifying a particular cannula type (such as, for example, cannula length, diameter, material, whether the cannula is straight or curved, whether the cannula is for a surgical instrument with an end effector or for an imaging instrument, and other parameters), a plurality of magnets may be used for the identification means of the exemplary embodiments described herein. For example, the identification device may include an array of magnets that are detected by a reader. Thus, not only can the magnetic polarity of the magnets used as identification devices be selectively predetermined to represent items of identification information, but the position of a particular magnet in the array can also be selectively predetermined so that the position of the magnet within the array also represents an item of information. When an array of magnets is present, the reader may be configured to determine not only whether a magnet is present in a particular orientation of the array, but also what the polarity of the magnet is. Thus, the presence or absence of a magnet at a particular location of the array of magnets and the polarity of the magnets may be associated with different parameters representing the identification information in a format that is detected by the reader. In this manner, the predetermined parameters of the one or more magnets may represent identification information for the cannula. For example, many combinations of presence, location, and polarity in the array may be implemented to provide multiple sets of unique identification information for different types of cannulae.

According to an exemplary embodiment, the presence or absence of a magnet at a given magnet position and the polarity of the magnet at the given magnet position can be used for unique identification information of the cannula (e.g., cannula material, cannula length, etc.), wherein the presence or absence of a magnet and the polarity of the magnet represent different values of a parameter of the identification information. According to another exemplary embodiment, the various values for the presence or absence of a magnet and the polarity of the magnet at various magnet positions of the identification device may be varied to provide various unique identifiers for different cannulas corresponding to a particular cannula. For example, rather than assigning a particular parameter of cannula identification information to a particular magnet position (e.g., changing the presence or absence at a particular location to indicate, for example, whether the cannula is made of metal or plastic), various values for the presence or absence and polarity of the magnet at various magnet positions of the identification device may be changed to provide a unique identifier that is similar to a unique serial number corresponding to a particular type of cannula. For example, a first unique combination of presence/absence and polarity (when present) of magnets at various magnet positions corresponds to a first sleeve type, a second unique combination of presence/absence and polarity (when present) of magnets at various magnet positions corresponds to a second sleeve type, and so on.

The array of magnets used in the identification devices of the example embodiments described herein may have a different number of magnets. Turning to fig. 8, an exemplary embodiment of an array 800 of four magnet positions 810 and 813 is shown for use with identification devices, such as, for example, the identification devices 614, 714 of the exemplary embodiments of fig. 6 and 7. Although the array 800 is described as including four magnet locations 810 and 813, the array 800 may include other numbers of magnet locations, such as, for example, two, three, five, six, seven, eight, or more magnet locations. Magnet locations 810 and 813 indicate locations where magnets may be positioned in array 800. In the exemplary embodiment of FIG. 8, array 800 includes a total of four magnets 820 and 823 located at respective magnet locations 810 and 813. The array 800 is located in the cannula, such as in an attachment portion of the cannula, such that the magnets 810 and 813 are detected by the reader to communicate identification information, as discussed above with respect to fig. 6.

According to an exemplary embodiment, each magnet position 810- "813 indicates a specific parameter that provides a portion of the identification information. Additionally, the presence or absence of a magnet at a particular magnet location may indicate a particular parameter that provides identifying information for the cannula. While a total of four magnets 820 & 823 are shown in the array 800 of the exemplary embodiment in FIG. 8, with the magnets 820 & 823 at respective magnet locations 810 & 813, the exemplary embodiments described herein are not limited to this embodiment. For example, various numbers of magnets may be located in an array comprising a plurality of magnet locations to indicate a parameter of the identification information using the presence or absence of a magnet at a particular magnet location. For example, a total of (n), (n-1), (n-2), (n-3), (n-4), (n-5) magnets, etc. may be used. According to an exemplary embodiment, the array of magnet locations comprises at least one magnet.

Additionally, the polarity of the magnet at each magnet location (when a magnet is present) may be predetermined to indicate a parameter of the identification information. For example, magnets 820 and 823, located at magnet positions 810 and 813, respectively, are all predetermined to have either a north or south polarity to be detected by the reader. According to an exemplary embodiment, when the reader detects the presence of north or south polarity for a particular magnet position, the reader thus also detects the presence of a magnet at the particular magnet position.

By varying the presence or absence of magnets and the polarity of the magnets at specific magnet locations in the array, various combinations of selection parameters can be generated to provide overall identification information of the cannula. For example, one magnet position may be used to indicate how many magnets are present in the array of magnets so that a surgical system including a reader can determine whether the correct number of magnets is detected. According to another example, various combinations of the presence/absence and polarity of the magnet may be used to provide a unique identifier similar to serial numbers of different cannula types. For example, in the arrangement of the exemplary embodiment of fig. 8, when considering four magnet positions 810 and 813 and three magnet states (e.g., magnet present in north polarity, magnet present in south polarity, or no magnet present), there are 81 possible unique combinations. The number of possible unique combinations may be modified according to the desired design. For example, it may be desirable to have a magnet present at all times so that at least one magnet can be detected to determine the presence of a cannula, which reduces the possible number of combinations by one because the combination of zero magnets present has been deleted.

By way of non-limiting example only, a possible explanation of how the magnet of fig. 8 can be similarly used for serial numbers to identify unique cannula types is provided below. In an exemplary embodiment, the array is designated to correspond to a standard disposable cannula when the magnet 821 is present at magnet location 811 and has a south polarity field and no magnet is located at any of the magnet locations 810, 812, or 813. The disposable sleeve may be made, for example, of plastic or other disposable sleeve materials known to those of ordinary skill in the art. For example, in one exemplary embodiment, the bowl portion 502, the tube portion 506, and the attachment portion 510 of the sleeve 500 of FIG. 5 are all made of a plastic material. According to an exemplary embodiment, a cannula made of plastic may include a single magnet to identify the cannula as a plastic cannula, such as a single magnet at location 811 (e.g., a magnet with a south polarity field). The magnet may be mounted on the plastic sleeve by, for example, overmolding the magnet with the plastic material of the sleeve, heat staking, adhesives, mounting a cap over the magnet, or other mounting methods known to those skilled in the art.

In another example, the array may be designated to correspond to a standard non-disposable sleeve when magnet 820 is present at magnet location 810 and has a south polarity field, magnet 821 is present at magnet location 811 and has a south polarity field, magnet 822 is present at magnet location 812 and has a south polarity field and no magnet is present at magnet location 813. In another example, the array is designated to correspond to a non-disposable sleeve having a long tube when magnet 820 is present at magnet location 810 and has a south polarity field, magnet 821 is present at magnet location 811 and has a north polarity field, magnet 822 is present at magnet location 812 and has a south polarity field and no magnet is present at magnet location 813. In another example, the array is designated to correspond to a standard non-disposable sleeve when magnet 820 is present at magnet location 810 and has a south polarity field, no magnet is present at the magnet location, magnet 822 is present at magnet location 812 and has a south polarity field, and magnet 823 is present at magnet location 813 and has a south polarity field.

Table 1 below provides the foregoing examples and additional examples where the magnet orientations correspond to the magnet orientations 810 and 813 of the exemplary embodiment of fig. 8. Table 1 includes examples of sensor signals from exemplary embodiments of readers that include sensors for detecting the presence/absence and polarity of magnets at each magnet. Thus, "N" in table 1 indicates the presence of a magnet having a north polarity, and "S" in table 1 indicates the presence of a magnet having a south polarity. "- - -" indicates the presence of no magnet.

TABLE 1

The configuration of the magnets in the array may be selected to minimize or eliminate interference. According to an exemplary embodiment, the page of FIG. 8 represents surfaces 616 and 716 in the exemplary embodiment of FIGS. 6 and 7, and the ends of magnets 820 and 823 are configured to extend out of the page of FIG. 8, such as along axis Z of FIG. 8. Extending the ends of the magnets 820-. The distances 814 and 816 along the respective axes X and Y may also be controlled in order to minimize or eliminate interference between the magnets 810 and 813, such as during manufacture of the cannula. For example, in an exemplary embodiment where no magnet is located at magnet position 810 but magnets 821 and 822 are located at magnet positions 811 and 812, respectively, magnet 821 at position 811 may be spaced a distance 814 from position 810 along axis X and magnet 822 at position 812 may be spaced a distance 816 from position 810 along axis Y to minimize false positive detection (positive detection) of the magnets at position 810 due to the magnetic fields of magnets 821 and 822. According to an exemplary embodiment, distances 814 and 816 are, for example, the distances between respective centers of magnet locations. According to an exemplary embodiment, distance 814 is a range from, for example, about 0.310 inches to about 0.330 inches, and distance 816 is a range from, for example, about 0.370 inches to about 0.390 inches.

Turning to fig. 9, an exemplary embodiment of a reader 900 is schematically illustrated. The reader 900 may be used with the exemplary embodiments described herein (such as the reader 622 of the exemplary embodiment of fig. 6 for a surgical system) to obtain identification information from an identification device. The reader 900 may be configured such that the reader is able to detect components of the identification device to obtain the identification information. For example, if the identification device contains an array of components having identification information (such as magnet 820-.

The reader 900 may contain one or more sensors for detecting components of the identification device. As discussed above with respect to the exemplary embodiment of fig. 6, reader 900 includes a single sensor to provide the functionality of the sensors described in the exemplary embodiments discussed herein. In another exemplary embodiment, reader 900 includes a plurality of sensors to provide the sensing functions discussed herein and described in the exemplary embodiments. For example, reader 900 includes a plurality of sensors, wherein respective sensors are configured to detect respective components of an identification device.

According to an exemplary embodiment, the reader 900 is configured to detect the magnets 820-. For example, when the cannula including the identification device 800 is connected to the arm of the surgical system, as discussed above with respect to the exemplary embodiment of fig. 4 and 6, the magnets 820-. Thus, the reader 900 may include four sensor sets 910- "913" corresponding to the four magnet positions 810- "813" of the identification device 800 in the exemplary embodiment of FIG. 8. However, the reader of the exemplary embodiments described herein is not limited to four sensor groups, and other numbers of sensor groups may be included according to the number of components of the identification device (such as the number of magnets). For example, the reader includes two, three, five, six, seven, eight, or more sensor groups. According to an exemplary embodiment, the distance 914 along axis X and the distance 916 along axis Y between the sensor sets in the exemplary embodiment of fig. 9 correspond to the distances 814 and 816, respectively, in the exemplary embodiment of fig. 8.

The reader may include one or more sensors in each sensor group of the reader. Although the sensor groups of various exemplary embodiments described herein may include a single sensor (including a single sensor to accomplish the various sensor functions described herein), each sensor group may instead include multiple sensors. As shown in the exemplary embodiment of FIG. 9, each sensor group 910-913 can include four sensors 920-923, although the exemplary embodiments described herein are not limited to readers that each include a sensor group having four sensors. Rather, each sensor group may include, for example, one, two, three, four, or more sensors. Turning to FIG. 10, an exemplary embodiment of a sensor cluster 1000 is schematically illustrated, the sensor cluster 1000 including four sensors 1010 and 1040. The sensor groups 1000 and sensors 1010-1040 are used, for example, in each of the sensor groups 910-913 of the exemplary embodiment of FIG. 9.

Because multiple types of identification information may be obtained from components of the identification device, the sensor group may include multiple sensors that perform multiple functions to obtain different types of identification information. For example, in the exemplary embodiment of FIG. 8, the presence or absence of the magnet 820-.

Accordingly, a sensor of a sensor group may be configured to detect whether a magnet is present at a magnet location, and other sensors of the sensor group may be configured to detect the polarity of the magnet present. For example, sensor 1010 in the exemplary embodiment of fig. 10 is a presence sensor configured to detect the presence of a magnet at the location of the magnet. According to an exemplary embodiment, in the event of a failure or malfunction of the sensor 1010, the sensor 1040 is also a presence sensor configured to detect the presence of a magnet to provide redundancy capabilities of the sensor group 1000 to detect the presence of a magnet. According to an exemplary embodiment, to detect the polarity of the magnet, sensor 1020 may be configured to detect a north polarity field and sensor 1030 may be configured to detect a south polarity field, or vice versa. While the sensors 1010, 1020, 1030, 1040 of the sensor group 1000 have been described above as having a particular function, the sensors 1010, 1020, 1030, 1040 can have different functions. For example, sensors 1010 and 1040 are polarity sensors and sensors 1020 and 1030 are presence sensors.

One type of sensor that may be used in a reader to detect a magnet is a hall effect device, as is well known to those of ordinary skill in the art. The hall effect device may be, for example, a hall effect sensor that may be configured to detect not only the presence of a magnet but also the polarity of a magnetic field. Hall effect sensors may include, for example, charge carriers (i.e., electrons and holes) flowing through a semiconductor (or conductor) that are deflected by an existing magnetic field, which deflection results in a potential difference that may be detected. Although various exemplary embodiments are described herein as using hall effect sensors, embodiments may use other hall effect devices and magnet sensors, such as, for example, magnetic loop sensors or hall effect switches configured to only detect the presence of a magnet, as well as other sensors known to those skilled in the art.

According to an exemplary embodiment, a Hall effect device for a reader (such as the sensors 1010, 1020, 1030, 1040 and 920-923 in the exemplary embodiments of FIGS. 9 and 10) may have a default high pressure state and a low pressure state, such as when a magnet is in proximity to the sensor. Turning to fig. 11, an exemplary embodiment of an output voltage (indicated by axis designation 1100) and a magnetic flux density (indicated by axis designation 1110) of a hall effect device is schematically illustrated.

Referring to fig. 11, when a magnet is not present in the hall effect device, the magnetic flux density 1110 is 0 and the hall effect device has a default voltage of 1120 (i.e., a "high" voltage state). Since the magnet with south polarity poles is adjacent to the hall effect device, as the magnetic flux density 1110 increases along path 1150, the output voltage remains high until the minimum operating point 1130 for the south polarity poles is reached. Once the minimum operating point 1130 is reached, the hall effect device can switch states to a voltage 1122 (i.e., a "low" voltage state). In fig. 11, the south polarity field is associated with magnetic flux on the right side, and the north polarity field is associated with magnetic flux on the left side, where the magnetic flux increases to 0 flux on the left and right sides for each polarity. A similar process occurs adjacent the north polar pole of the sensor, wherein as magnetic flux 1110 increases along path 1160, the voltage level remains high until the magnetic flux drops between the minimum operating point 1140 and the maximum operating point 1142 of the north polar pole, at which point the sensor switches to voltage 1122, such as along path 1162. Although the exemplary embodiment of fig. 11 shows the hall effect device switching to the voltage 1122 at the minimum operating point 1130 and at the minimum operating point 1140 along the path 1162 along the path 1152, the hall effect device may switch to the voltage 1122 at any amount of flux within a flux release band defined between the respective minimum operating point 1130, 1132 and maximum operating point 1140, 1142.

As the distance between the hall effect device and the magnetic pole increases, the magnetic flux 1110 decreases, such as by moving the magnetic pole away from the adjacent hall effect device, such as toward 0 magnetic flux along path 1154 for south polarity fields or path 1164 for north polarity fields. Once the magnetic flux 1110 drops to a value that drops within a release point band, such as between the maximum release point 1136 and the minimum release point 1134 of the south polarity field or between the maximum release point 1146 and the minimum release point 1144 of the north polarity field, the hall effect device returns to its default voltage 1120 ("high" voltage state), indicating that a magnetic field is not present. Although the exemplary embodiment of fig. 11 shows the hall effect device switching to the voltage 1120 at the minimum release point 1134 along path 1156 and the minimum release point 1166 along path 1166, the hall effect device may switch to the voltage 1120 at any magnetic flux value within a magnetic flux release band defined between the respective minimum release point 1134, 1136 and maximum release point 1144, 1146.

The exemplary embodiment of fig. 11 may be used for magnet presence sensors (such as sensors 1010 and 1040 of the exemplary embodiment of fig. 10) and magnetic pole sensors (such as sensors 1020 and 1030 of the exemplary embodiment of fig. 10). While these different types of sensors may exhibit different release point values, operating point values, and/or voltage values, as will be discussed below, in other respects will operate in the general manner discussed with respect to the exemplary embodiment of fig. 11. For example, when the hall effect device has a voltage 1122, the hall effect device indicates the presence of a magnet, such as when the sensor is one of the sensors 1010 and 1040 of the exemplary embodiment of fig. 10. When a hall effect device is configured to detect magnetic polarity (e.g., by using a hall effect sensor), such as devices 1020 and 1030 of the exemplary embodiment of fig. 10, voltage 1122 may be used to indicate the polarity of the sensed magnetic pole.

According to an exemplary embodiment, the hall effect devices used to detect the presence of a magnet (such as sensors 1010 and 1040 of the exemplary embodiment of fig. 10) are all-pole sensors that detect the presence of either a north-pole or south-pole. Thus, when a south polarity pole or a north polarity pole is adjacent to the sensor, the all-polarity presence sensor may follow path 1150 or 1160. In contrast, according to an exemplary embodiment, the sensor for detecting the polarity of the magnetic pole may be a single-polarity sensor configured to detect only one type of magnetic polarity. As discussed above with respect to the exemplary embodiment of fig. 10, sensor 1020 may be configured to detect a north-polarity field (rather than a south-polarity field) and thus follow path 1160 when a north-polarity magnet is proximate to sensor 1020, while sensor 1030 may be configured to detect a south-polarity field (rather than a north-polarity field) and follow path 1150 when a south-polarity magnet is proximate to sensor 1030. A single-polarity sensor will not respond to a magnetic field having a magnetic pole that is not designed for detection.

The release point value for the sensor may be selected to minimize or prevent interference from magnetic fields that do not originate from the magnet to be detected by the sensor. According to an exemplary embodiment, the presence sensor has a minimum release point 1134, 1144 that has a higher value than the minimum release point 1134, 1144 for the polarity sensor. In this way, although the detection of the magnetic field by the polarity sensor may inherently indicate the presence of a magnet, the presence sensor is less sensitive to the magnetic field from a source other than a magnet adjacent to the presence sensor, such as other magnets in the array of identification devices. According to an exemplary embodiment, because the polar sensor may have a lower release point value than the presence sensor, the controller receiving the signal from the reader may be configured to ignore the detection signal from the polar sensor unless the presence sensor (or all presence sensors if a redundant presence sensor is used, as in the exemplary embodiment of fig. 10 sensors 1010 and 1040) also indicate detection of a magnetic field. Thus, the presence sensor may be used to verify the presence of a magnet detected by the polarity sensor, wherein sensor detection by the polarity sensor is ignored unless at least one presence sensor in the same array also detects the magnet. According to an exemplary embodiment, the polarity sensor of the exemplary embodiments discussed herein has a value for the minimum release point 1134, 1144, for example, ranging from about 7 gauss to about 9 gauss. The presence sensors of the exemplary embodiments discussed herein have values for the minimum release points 1134, 1144, for example, ranging from about 11 gauss to about 13 gauss.

According to an exemplary embodiment, the presence sensors and polarity sensors of the exemplary embodiments discussed herein have maximum operating points 1132, 1142 ranging, for example, from about 50 gauss to about 60 gauss, although the presence sensors and polarity sensors may have different values for operating points 1130, 1132, 1140, 1142. Examples of presence sensors are Piano, Texas

Model AH1892, inc. Examples of unipolar sensors are Kyoto, Japan's model numbers BU52002GUL and BU52003GUL of ltd.

The detection signal from the sensor may be transmitted to and interpreted by a controller (such as by transmission line 626 of the exemplary embodiment of fig. 6), such as a controller of a surgical system. The surgical system may interpret the signals from the various sensors of the reader to determine what identification information has been obtained and then identify the type of cannula represented by the identification information. The signal from the sensor can also be analyzed for sensor errors. According to an exemplary embodiment, the signal from the sensor of the reader is also analyzed to determine whether the sensor provides an error signal or whether the sensor is malfunctioning. For example, a reader includes multiple presence sensors to provide redundancy in the presence detection capabilities of the reader such that if one presence sensor fails, another presence sensor detects a component of the identification device. Additionally, if the unipolar sensors are used to detect north or south polarity fields, the controller may determine that one of the unipolar sensors is malfunctioning when the unipolar sensors indicate the presence of a magnetic field. Conversely, if the presence sensor(s) of the reader indicate the presence of the magnet, but no polarity sensor indicates the polarity of the field of the magnet, this indicates that at least one unipolar sensor is malfunctioning.

The following table provides an example of sensor signals from an exemplary embodiment of a reader that includes four sensors, two of which are all-polar hall effect presence devices ("P/a" in table 2), such as devices 1010 and 1040 of the exemplary embodiment of fig. 10, one of which is a unipolar hall effect polarity sensor that detects a north polarity field ("north" in table 2), such as device 1020 in the exemplary embodiment of fig. 10, and one of which is a unipolar hall effect sensor that detects a south polarity field ("south" in table 2), such as device 1020 in the exemplary embodiment of fig. 10. A value of "1" indicates a high state (e.g., voltage 1120 of fig. 11), which is a default state indicating no detection, and a value of "0" indicates a low state (e.g., voltage 1122 of fig. 11), which is a detection state. An "X" indicates that either a "1" or a "0" may exist but that either value does not affect the generation of the result.

TABLE 2

P/A	P/A	Arctic sensor	Antarctic sensor	Results
					1	1	X	X	Absence of magnet
0	0	1	0	The magnet being present in the south pole
					0	0	0	1	The magnet being present at the north pole
1	0	X	X	Error: bad presence sensor
					0	1	X	X	Error: bad presence sensor
0	0	1	1	Error: bad polarity sensor
					0	0	0	0	Error: bad polarity sensor

According to an exemplary embodiment, feedback is provided to the user, such as by displaying the identification of the cannula to the user. According to an exemplary embodiment, the controller is programmed to expect a cannula having a particular identification for a surgical procedure, and if the identification information determined from the sensor signal does not match the programmed identification information, feedback may be provided to the user, such as by visual and/or audio feedback to inform the user of the unmatched identification information. According to an exemplary embodiment, the surgical system prevents use of the patient side cart, including the arm and the instrument connected to the arm of the patient side cart, when the determined identification information does not match the programmed identification information.

The various exemplary embodiments described herein include other uses for identification information for cannulas, including but not limited to, for example, verifying that a cannula is made of metal (e.g., such as when an electrosurgical instrument is used with a cannula), verifying that a cannula matches a cannula type to be used with a particular instrument, notifying a surgical system of the length of a cannula (e.g., notifying a surgical system of the cannula length), notifying a surgical system of the presence of a cannula so that safety features (e.g., patient side cart stabilization features and features for stabilizing a patient side cart) can be engaged, as well as other features related to cannulas used with a surgical system.

While the exemplary embodiments of fig. 8-10 have been discussed with respect to readers that include sensor groups that each include four sensors (such as sensors 920-923 of fig. 9 and sensors 1010, 1020, 1030, 1040 of fig. 10), the sensor groups of readers may include other numbers of sensors. Turning to fig. 12-14, various sensor groups 1200, 1300, 1400 are shown that can be used with the readers of the exemplary embodiments discussed above.

In fig. 12, an exemplary embodiment of a sensor group 1200 is shown that includes three sensors 1210, 1220, and 1230. According to an exemplary embodiment, two of the sensors 1210, 1220, and 1230 are unipolar sensors and two of the sensors 1210, 1220, and 1230 are unipolar sensorsOne of which is a full polarity presence sensor as discussed in the exemplary embodiment with respect to fig. 11. According to another exemplary embodiment, two of the sensors 1210, 1220, and 1230 are all-polar presence sensors to provide presence sensing redundancy, and one of the sensors 1210, 1220, and 1230 is a dual-output unipolar sensor that detects north and south polarity fields. According to an exemplary embodiment, while the dual-output unipolar sensor is capable of detecting north and south polarity fields due to its dual outputs, the minimum release points 1134, 1144 for the dual-output unipolar sensor have a lower value than the minimum release points 1134, 1144 for the unipolar sensor, making the dual-output unipolar sensor more sensitive to stray magnetic fields than a unipolar sensor without the dual outputs. An example of a dual output unipolar sensor is Allegro Microsystems, Inc. (Worcester, MA)

Model a1171 from Microsystems, inc.

In fig. 13, an exemplary embodiment of a sensor group 1300 is shown, which includes two sensors 1310 and 1320. One of the sensors 1310 and 1320 may be a full polarity presence sensor, as discussed above with respect to the exemplary embodiment of fig. 11, and the other of the sensors 1310 and 1320 may be a dual output single polarity sensor capable of detecting north and south polarity fields, as discussed above with respect to the exemplary embodiment of fig. 13. In fig. 14, an exemplary embodiment of a sensor group 1400 is shown that includes a single sensor 1410 that is a dual output single polarity sensor. A single sensor 1410 may be used without any confirmation from the presence sensor by interpreting the detection of either a north or south polarity field as indicating the presence of a magnet.

While identification and reader embodiments have been discussed above in terms of the use of magnets and sensors for detecting magnets, other types of identification devices and sensors may be used with the exemplary embodiments described herein. According to an exemplary embodiment, the identification means comprises a magnet having a predetermined orientation, the predetermined orientation representing identification information, the identification information being detected by the reader. Turning to fig. 15, an exemplary embodiment of a magnet 1510 is shown, the magnet 1510 protruding from a surface 1520, which may be the sleeve surface 616 or 716 in the exemplary embodiments of fig. 6 and 7. Magnet 1510 may be a cylindrical magnet that has been selectively oriented such that the magnetic field of magnet 1510 is oriented in a predetermined direction. According to an exemplary embodiment, magnet 1510 is oriented such that the magnetic field of the pole at magnet end 1516 is oriented along direction 1512 relative to predetermined reference direction 1514. The reader may include a sensor for detecting an angle 1518 between directions 1514 and 1516, wherein the identification angle conveys identification information to the reader. For example, the sensor detects the magnetic field direction of the magnet of the identification device. According to an exemplary embodiment, the sensor is capable of detecting an angle 1518 for the direction of the magnetic field. The magnetic field direction sensor may be, for example, a magnetic rotation sensor that includes one or more linear hall effect devices to detect the strength of a magnetic field in a particular direction and then analyze that particular direction to determine the angle of the magnetic poles relative to the magnetic field direction sensor. According to an exemplary embodiment, the magnetic field direction sensor uses mapping sensor angle values to correct for deviations in the field direction, such as due to the magnetic field of other magnets and/or other nearby magnet materials.

Another type of identification device that may be used in the exemplary embodiments described herein is a Radio Frequency Identification (RFID) device. According to an exemplary embodiment, the RFID device comprises a device located within the cannula, wherein the device comprises electronically stored identification information obtained by the reader. For example, the reader may emit an electromagnetic field that activates a device in the casing that in turn emits identification information to be detected by the reader.

Although the exemplary embodiments herein have been described for identifying a casing, the exemplary embodiments are used for identification of other objects than a casing. For example, the exemplary embodiments described herein are used to identify other surgical and non-surgical devices, such as, for example, devices that may be matched to a corresponding system in which the device is used.

While the readers of the exemplary embodiments described herein may be described as part of a surgical system, such as, for example, a robotic arm of a patient side cart, the readers of the exemplary embodiments described herein may also be used as manual devices. For example, the reader may be a handheld device that the user uses to quickly identify various cannulas without using the surgical system.

By providing the identification means with a cannula for a surgical system, the cannula is accurately identified, including a plurality of unique features of the particular cannula. The identification means identifies the bushing without using electronic parts on the bushing, so that the identification means is low in complexity and low in cost. In addition, the identification device is durable and can be used over the useful life of the cannula, even when the cannula is cleaned, such as by autoclaving.

Further modifications and alternative embodiments will become apparent to those skilled in the art in view of this disclosure. For example, the systems and methods may include additional components or steps that have been omitted from the figures and description for clarity of operation. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the present teachings. It should be understood that the various embodiments shown and described herein are to be considered exemplary. Elements and materials, and arrangements of such elements and materials, may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the present teachings may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of the description herein. Changes may be made in the elements described herein without departing from the spirit and scope of the disclosure and the following claims.

It is understood that the specific examples and embodiments set forth herein are not limiting and that modifications in structure, size, materials, and method may be made without departing from the scope of the disclosure.

Other embodiments in accordance with the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a full scope of the claims and their equivalents being granted.