阅读说明：本技术 根据端部执行器的关节运动角度控制外科缝合和切割器械的马达速度的系统和方法 (System and method for controlling motor speed of a surgical stapling and severing instrument as a function of an articulation angle of an end effector ) 是由 F·E·谢尔顿四世 D·C·耶茨 J·L·哈里斯 于 2018-05-16 设计创作，主要内容包括：本发明公开了一种机动化外科器械。该外科器械包括位移构件、马达、控制电路和位置传感器。该位移构件被构造成能够平移。该马达联接到位移构件以使该位移构件平移。该控制电路联接到该马达。该位置传感器联接到控制电路。该位置传感器被配置为能够测量位移构件的位置并且测量端部执行器相对于纵向延伸轴的关节运动角度。该控制电路被配置为能够确定端部执行器和纵向延伸轴之间的关节运动角度并且基于关节运动角度设定马达速度。(The invention discloses a motorized surgical instrument. The surgical instrument includes a displacement member, a motor, a control circuit, and a position sensor. The displacement member is configured to translate. The motor is coupled to the displacement member to translate the displacement member. The control circuit is coupled to the motor. The position sensor is coupled to the control circuit. The position sensor is configured to measure a position of the displacement member and to measure an articulation angle of the end effector relative to the longitudinally extending shaft. The control circuit is configured to determine an articulation angle between the end effector and the longitudinally extending shaft and set a motor speed based on the articulation angle.)

1. A surgical instrument, comprising:

a displacement member;

a motor coupled to the displacement member to translate the displacement member;

a control circuit coupled to the motor;

a position sensor coupled to the control circuit, the position sensor configured to measure a position of the displacement member and configured to measure an articulation angle of an end effector relative to a longitudinally extending shaft;

wherein the control circuitry is configured to be capable of:

determining the articulation angle between the end effector and the shaft;

selecting a force threshold based on the articulation angle;

setting a motor speed based on the articulation angle;

determining a force on the displacement member; and

adjusting the motor speed when the force on the displacement member is greater than the force threshold.

2. The surgical instrument of claim 1, wherein the control circuit is configured to determine an actual position of the displacement member.

3. The surgical instrument of claim 1, wherein the control circuit is configured to determine an end of a firing stroke of the displacement member.

4. The surgical instrument of claim 1, wherein the control circuit is configured to compare the force on the displacement member to the force threshold.

5. The surgical instrument of claim 1, further comprising a timer/counter circuit coupled to the control circuit, the timer/counter circuit configured to measure elapsed time;

wherein the control circuitry is configured to be capable of:

setting the motor speed;

receiving an initial position of the displacement member from the position sensor;

receiving a reference time t corresponding to the initial position of the displacement member from the timer/counter circuit ₁(ii) a And

determining the displacement member at time t based on the motor speed ₂The expected location of the device.

6. The surgical instrument of claim 5, wherein the control circuit is configured to:

receiving the displacement member at the time t from the position sensor ₂The actual position of (a);

displacing the member at the time t ₂With the displacement member at the time t ₂Comparing the expected locations of; and

based on the displacement member at the time t ₂And the displacement member at the time t ₂To determine a force on the displacement member.

7. The surgical instrument of claim 1, wherein the control circuit is configured to reduce the motor speed until a force on the displacement member is less than the force threshold.

8. A surgical instrument, comprising:

a displacement member;

a motor coupled to a proximal end of the displacement member to translate the displacement member;

a control circuit coupled to the motor;

a position sensor coupled to the control circuit, the position sensor configured to measure a position of the displacement member relative to an end effector and configured to measure an articulation angle of the end effector relative to a longitudinally extending axis;

wherein the control circuitry is configured to be capable of:

determining the articulation angle between the end effector and the longitudinally extending shaft; and

setting a motor speed based on the articulation angle.

9. The surgical instrument of claim 8, wherein the control circuit is configured to determine an actual position of the displacement member.

10. The surgical instrument of claim 8, wherein the control circuit is configured to determine an end of a firing stroke of the displacement member.

11. The surgical instrument of claim 8, wherein the control circuit is configured to compare the articulation angle to a previous articulation angle.

12. The surgical instrument of claim 11, wherein the control circuit is configured to adjust the set motor speed based on the new articulation angle.

13. The surgical instrument of claim 8, further comprising a timer/counter circuit coupled to the control circuit, the timer/counter circuit configured to measure elapsed time;

wherein the control circuitry is configured to be capable of:

setting the motor speed;

receiving an initial position of the displacement member from the position sensor;

receiving a reference time t corresponding to the initial position of the displacement member from the timer/counter circuit ₁(ii) a And

determining the displacement member at time t based on the set motor speed ₂The expected location of the device.

14. The surgical instrument of claim 13, wherein the control circuit is configured to:

receiving the displacement member at the time t from the position sensor ₂The actual position of (a);

displacing the member at the time t ₂With the I-beam member at said time t ₂Comparing the expected locations of; and

based on the displacement member at the time t ₂And the displacement member at the time t ₂To determine a force on the displacement member.

15. A method of controlling motor speed in a surgical instrument, the surgical instrument comprising a displacement member, a motor coupled to the displacement member to translate the displacement member, a control circuit coupled to the motor, and a position sensor coupled to the control circuit, the position sensor configured to measure a position of the displacement member and configured to measure an articulation angle of an end effector relative to a longitudinally extending shaft, the method comprising:

determining, by the control circuit, an articulation angle between the end effector and the longitudinally extending shaft; and

setting, by the control circuit, a motor speed based on the articulation angle.

16. The method of claim 15, further comprising:

selecting, by the control circuit, a force threshold based on the articulation angle;

determining, by the control circuit, a force on the displacement member; and

adjusting, by the control circuit, the motor speed when the force on the displacement member is greater than the force threshold.

17. The method of claim 15, further comprising determining, by the control circuit, an actual position of the displacement member.

18. The method of claim 15, further comprising determining, by the control circuit, an end of a firing stroke of the displacement member.

19. The method of claim 15, further comprising comparing, by the control circuit, the articulation angle to a previous articulation angle.

20. The method of claim 19, further comprising adjusting, by the control circuit, the motor speed based on the new articulation angle.

Technical Field

The present disclosure relates to surgical instruments and, in various instances, to surgical stapling and cutting instruments and staple cartridges therefor that are designed for stapling and cutting tissue.

Background

In motorized surgical stapling and cutting instruments, it may be useful to control the speed of the cutting member or to control the speed of articulation of the end effector. The velocity of the displacement member may be determined by measuring the elapsed time of a predetermined interval of positions of the displacement member or measuring the position of the displacement member at a predetermined interval of time. The control may be open loop or closed loop. Such measurements may be used to assess tissue conditions such as tissue thickness, and to adjust the speed of the cutting member during the firing stroke to account for the tissue conditions. The tissue thickness may be determined by comparing the expected speed of the cutting member with the actual speed of the cutting member. In some cases, it may be useful to articulate the end effector at a constant articulation speed. In other cases, it may be useful to drive the end effector at an articulation speed that is different from a default articulation speed at one or more regions within the scanning range of the end effector.

The firing force or load experienced by the cutting member or firing member during use of the motorized surgical stapling and severing instrument may vary or increase based on the articulation angle of the end effector. Accordingly, it may be desirable to vary the firing speed of the cutting member or firing member depending on the articulation angle of the end effector to reduce the force of the firing load on the cutting member or firing member due to increasing the articulation angle of the end effector.

Disclosure of Invention

In one aspect, the present disclosure provides a surgical instrument. The surgical instrument includes a displacement member configured to translate; a motor coupled to the proximal end of the displacement member to translate the displacement member; a control circuit coupled to the motor; a position sensor coupled to the control circuit, the position sensor configured to measure a position of the displacement member and configured to measure an articulation angle of the end effector relative to the longitudinally extending shaft; wherein the control circuitry is configured to be capable of: determining an articulation angle between the end effector and the longitudinally extending shaft; selecting a force threshold based on the articulation angle; setting a motor speed based on the articulation angle; determining a force on the displacement member; and adjusting the motor speed when the force on the displacement member is greater than the force threshold.

In another aspect, the surgical instrument comprises: a displacement member configured to translate; a motor coupled to the displacement member to translate the displacement member; a control circuit coupled to the motor; a position sensor coupled to the control circuit, the position sensor configured to measure a position of the displacement member relative to the end effector and configured to measure an articulation angle of the end effector relative to the longitudinally extending shaft; wherein the control circuitry is configured to be capable of: determining an articulation angle between the end effector and the longitudinally extending shaft; and setting a motor speed based on the articulation angle.

In another aspect, the present invention provides a method of controlling motor speed in a surgical instrument including a displacement member configured to translate, a motor coupled to the displacement member to translate the displacement member, a control circuit coupled to the motor, and a position sensor coupled to the control circuit, the position sensor configured to measure a position of the displacement member and configured to measure an articulation angle of an end effector relative to a longitudinally extending shaft, the method comprising: determining, by the control circuit, an articulation angle between the end effector and the longitudinally extending shaft; and setting, by the control circuit, a motor speed based on the articulation angle.

Drawings

The novel features believed characteristic of the aspects described herein are set forth with particularity in the appended claims. These aspects, however, both as to organization and method of operation, may best be understood by reference to the following description taken in conjunction with the accompanying drawings.

Fig. 1 is a perspective view of a surgical instrument having an interchangeable shaft assembly operably coupled thereto according to one aspect of the present disclosure.

Fig. 2 is an exploded assembly view of a portion of the surgical instrument of fig. 1, according to one aspect of the present disclosure.

FIG. 3 is an exploded assembly view of portions of an interchangeable shaft assembly according to one aspect of the present disclosure.

FIG. 4 is an exploded view of an end effector of the surgical instrument of FIG. 1 according to one aspect of the present disclosure.

Fig. 5A-5B are block diagrams of control circuitry of the surgical instrument of fig. 1 spanning two pages according to one aspect of the present disclosure.

Fig. 6 is a block diagram of the control circuit of the surgical instrument of fig. 1 illustrating the handle assembly and the power assembly and the interface between the handle assembly and the interchangeable shaft assembly according to one aspect of the present disclosure.

Fig. 7 illustrates a control circuit configured to control aspects of the surgical instrument of fig. 1, according to one aspect of the present disclosure.

Fig. 8 illustrates a combinational logic circuit configured to control aspects of the surgical instrument of fig. 1, according to one aspect of the present disclosure.

Fig. 9 illustrates sequential logic circuitry configured to control aspects of the surgical instrument of fig. 1, according to one aspect of the present disclosure.

Fig. 10 is a schematic diagram of an absolute positioning system of the surgical instrument of fig. 1, wherein the absolute positioning system includes a controlled motor drive circuit arrangement including a sensor arrangement, according to one aspect of the present disclosure.

Fig. 11 is an exploded perspective view of a sensor arrangement of an absolute positioning system, showing a control circuit board assembly, and the relative alignment of elements of the sensor arrangement, according to one aspect of the present disclosure.

FIG. 12 is a schematic diagram of a position sensor including a magnetic rotary absolute positioning system according to one aspect of the present disclosure.

FIG. 13 is a cross-sectional view of the end effector of the surgical instrument of FIG. 1 illustrating the firing member stroke relative to tissue grasped within the end effector, according to one aspect of the present disclosure.

Fig. 14 illustrates a block diagram of a surgical instrument programmed to control distal translation of a displacement member according to one aspect of the present disclosure.

Fig. 15 shows a graph plotting two example displacement member strokes performed in accordance with an aspect of the present disclosure.

FIG. 16 is a partial perspective view of a portion of an end effector of a surgical instrument showing an elongate shaft assembly in a non-articulating orientation with portions thereof omitted for clarity in accordance with an aspect of the present disclosure.

FIG. 17 is another perspective view of the end effector of FIG. 16 showing the elongate shaft assembly in an unarticulated orientation, according to one aspect of the present disclosure.

Fig. 18 is an exploded assembly perspective view of the end effector of fig. 16, illustrating elongate shaft assembly aspects, according to one aspect of the present disclosure.

FIG. 19 is a top view of the end effector of FIG. 16 showing the elongate shaft assembly in an unarticulated orientation, according to one aspect of the present disclosure.

FIG. 20 is another top view of the end effector of FIG. 16 showing the elongate shaft assembly in a first articulation orientation in accordance with an aspect of the present disclosure.

FIG. 21 is another top view of the end effector of FIG. 16 showing the elongate shaft assembly in a second articulation orientation in accordance with an aspect of the present disclosure.

FIG. 22 is a graph of displacement member velocity as a function of end effector articulation angle in accordance with one or more aspects of the present disclosure.

FIG. 23 is a graph of displacement member force as a function of firing stroke displacement of the displacement member in accordance with one or more aspects of the present disclosure.

FIG. 24 is a graph of displacement member force as a function of firing stroke displacement of the displacement member in accordance with one or more aspects of the present disclosure.

Fig. 25 is a graph of displacement member velocity as a function of linear displacement stroke displacement of the displacement member according to one or more aspects of the present disclosure.

FIG. 26 is a logic flow diagram depicting a process of a control program or logic configuration for controlling the velocity of a displacement member (such as an I-beam member) based on an articulation angle of an end effector in accordance with one or more aspects of the present disclosure.

FIG. 27 is a logic flow diagram depicting a process of a control routine or logic configuration for controlling the rate of a displacement member (such as an I-beam member) based on an articulation angle of an end effector in accordance with one or more aspects of the present disclosure.

Detailed Description

The applicant of the present application owns the following patent applications filed concurrently with the present application and each incorporated herein by reference in its entirety:

attorney docket No. END8191USNP/170054 entitled "MOTOR speed CONTROL OF surgical stapling and severing INSTRUMENT BASED ON ARTICULATION ANGLE" (CONTROL OF MOTOR vehicle OF surgical system STAPLING AND CUTTING insertion base ON ANGLE OF ARTICULATION) "filed by inventor Frederick e.shelton, IV et al ON 2017 ON 20/6.

The attorney docket No. END8192USNP/170055 entitled "SURGICAL INSTRUMENT WITH VARIABLE DURATION trigger arrangement (SURGICAL INSTRUMENT WITH VARIABLE DURATION trigger arrangement)" filed by inventor Frederick e.shelton, IV et al on 2017 at 20/6.

The system and method FOR controlling the movement OF a displacement MEMBER OF a SURGICAL stapling and severing INSTRUMENT filed 2017 on 20.6.7 by Frederick E.Shelton, IV et al, entitled "System and method FOR controlling the movement OF a displacement MEMBER OF a SURGICAL stapling and severing INSTRUMENT" (SYSTEMS AND METHODS FOR controlling tissue positioning OF A SURGICAL STAPLING AND CUTTING INSTRUMENT) "attorney docket No. END8193 USNP/170056.

The attorney docket number END8195USNP/170058 entitled "system and method FOR CONTROLLING motor speed OF SURGICAL stapling and severing INSTRUMENT" (SYSTEMS AND METHODS FOR CONTROLLING motor rotation OF a SURGICAL stapling STAPLING AND CUTTING INSTRUMENT) "filed by Frederick e.shelton, IV et al on 2017, month 6 and 20.

The attorney docket No. END8196USNP/170059 entitled "SURGICAL INSTRUMENT with controlled joint movement velocity (SURGICAL INSTRUMENT with controlled articulation velocity)" filed by inventor Frederick e.shelton, IV et al on 2017, month 6 and 20.

The system and method entitled "controlling the speed OF a displacement MEMBER OF a SURGICAL stapling and severing instrument (SYSTEMS AND METHODS FOR controlling the displacement OF A DISPLACEMENT MEMBER OF A SURGICAL STAPLING AND CUTTING NSTRUMENT)" filed by inventor Frederick E.Shelton, IV et al on 2017, 20.6.8, attorney docket number END8197 USNP/170060.

The attorney docket number END8198USNP/170061 entitled "system and method FOR CONTROLLING the speed of a SURGICAL INSTRUMENT displacement member" (SYSTEMS AND METHODS FOR CONTROLLING the displacement of a SURGICAL INSTRUMENT, display device VELOCITY FOR a SURGICAL INSTRUMENT) filed by inventor Frederick e.shelton, IV et al on 2017, month 6 and 20.

The attorney docket No. END8222USNP/170125 entitled "MOTOR speed CONTROL OF surgical stapling and severing INSTRUMENT BASED ON ARTICULATION ANGLE" (CONTROL OF MOTOR vehicle OF surgical system OF STAPLING AND CUTTING insertion base ON ANGLE) filed by inventor Frederick e.shelton, IV et al ON 2017 ON 20/6 months.

Attorney docket No. END8199USNP/170062M entitled "ADAPTIVE CONTROL technique FOR controlling motor speed OF SURGICAL stapling and CUTTING INSTRUMENT" (TECHNIQUES FOR ADAPTIVE CONTROL OF A SURGICAL STAPLING AND CUTTING INSTRUMENT), filed by inventor Frederick e.shelton, IV et al on 2017, month 6, and 20.

Attorney docket number END8275USNP/170185M entitled "technique FOR CLOSED LOOP CONTROL OF SURGICAL stapling and CUTTING INSTRUMENT motor speed" (TECHNIQUES FOR CLOSED LOOP CONTROL OF MOTORVELEMENT OF A SURGICAL STAPLING AND CUTTING INSTRUMENT) "filed on 20.6.2017 by inventor Raymond E.

A attorney docket No. END8268USNP/170186 entitled "CLOSED LOOP FEEDBACK CONTROL OF MOTOR SPEED OF SURGICAL SETTING AND CUTTING INSTRUMENT BASED ON METHOD OF CONTRACTIVE OF VELOCITY MEASUREMENT", filed 2017, 20/6/7 by Raymond E.Parfett et al.

The inventor's Jason L.Harris et al, filed 2017 on 20.6, entitled "CLOSED LOOP feedback control OF Motor speed OF SURGICAL stapling and severing INSTRUMENT based on TIME MEASURED OVER specified displacement distance (CLOSED Loop feedback control OF Motor speed STAPLING AND CUTTING INSTRUMENTS BASED MEASURED TIME OVER A SPECIFIED DISPLACEMENT DISTANCE)", attorney docket number END8276 USNP/170187.

Shelton, IV et al, Frederick E.Shorton, U.S. 2017, attorney docket number END8266USNP/170188 entitled "CLOSED LOOP FEEDBACK CONTROL OF MOTOR speed OF SURGICAL STAPLING and cutting INSTRUMENT BASED ON MEASURED displacement distance traveled OVER specified time interval (CLOSED LOOP FEEDBACK CONTROL OF A SURGICAL STAPLING AND DCUTING INSTRUMENTS BASED DISPLACEMENT DISTANCE TRAVELED OVER ASPECIFIED TIME INTERVAL)".

The attorney docket No. END8267USNP/170189 entitled "CLOSED loop feedback CONTROL OF MOTOR speed OF SURGICAL stapling and cutting instrument BASED ON MEASURED TIME OVER specified NUMBER OF shaft rotations (CLOSED loop feedback system MEASURED TIME OVER A SPECIFIED NUMBER OF short procedure) filed by inventor Frederick e.shelton, IV et al ON 2017 ON 20.6.7.

An attorney docket No. END8269USNP/170190 entitled "system and method FOR CONTROLLING and DISPLAYING motor speed of SURGICAL INSTRUMENT" (SYSTEMS AND METHODS FOR CONTROLLING display motor speed FOR SURGICAL INSTRUMENT) filed by inventor Jason l harris et al on 20/6/2017.

The system and method FOR CONTROLLING MOTOR speed in accordance with USER INPUT TO a SURGICAL INSTRUMENT (SYSTEMS AND METHODS FOR CONTROLLING MOTOR speed FOR USER INPUT FOR a MOTOR speed instrment) filed by inventor Jason l.harris et al on 20.6.2017, attorney docket number END8270 USNP/170191.

The attorney docket number END8271USNP/170192 entitled "CLOSED LOOP FEEDBACK control OF MOTOR speed OF SURGICAL stapling and severing INSTRUMENT BASED on System CONDITIONS" filed by Frederick E.Shelton, IV et al on 2017 on 20.6.7.

The applicant of the present application owns the following U.S. design patent applications filed concurrently with the present application and each incorporated herein by reference in its entirety:

the attorney docket number END8274USDP/170193D entitled "graphical user interface for display or portion thereof (GRAPHICAL USER INTERFACE FOR A DISPLAY OR PORTION THEREOF)" filed by inventor Jason l harris et al on 20.6.2017.

The attorney docket number END8273USDP/170194D entitled "graphical user interface for display or portion thereof (GRAPHICAL USER INTERFACE FOR A DISPLAY OR PORTION THEREOF)" filed by the inventor on 20.6.2017 by Jason l.

The attorney docket number END8272USDP/170195D entitled "graphical user interface for display or portion thereof (GRAPHICAL USER INTERFACE FOR A DISPLAY OR PORTIONTHEREOF)" filed by inventor Frederick e.shelton, IV et al on 2017 on month 6 and 20.

Certain aspects are shown and described to provide an understanding of the structure, function, manufacture, and use of the disclosed apparatus and methods. Features illustrated or described in one example may be combined with features of other examples, and modifications and variations are within the scope of the disclosure.

The terms "proximal" and "distal" are relative to a clinician manipulating a handle of a surgical instrument, where "proximal" refers to a portion closer to the clinician and "distal" refers to a portion farther from the clinician. For convenience, the spatial terms "vertical," "horizontal," "upward," and "downward" used with respect to the drawings are not intended to be limiting and/or absolute, as the surgical instrument may be used in many orientations and positions.

Example devices and methods are provided for performing laparoscopic and minimally invasive surgical procedures. However, such devices and methods may be used for other surgical procedures and applications, including, for example, open surgical procedures. The surgical instrument may be inserted through a natural orifice or through an incision or puncture formed in the tissue. The working portion or end effector portion of the instrument can be inserted directly into the body or through an access device having a working channel through which the end effector and elongate shaft of the surgical instrument can be advanced.

Fig. 1-4 depict a motor-driven surgical instrument 10 for cutting and fastening that may or may not be reusable. In the illustrated example, the surgical instrument 10 includes a housing 12 including a handle assembly 14 configured to be grasped, manipulated and actuated by a clinician. The housing 12 is configured for operable attachment to an interchangeable shaft assembly 200 having an end effector 300 operably coupled thereto that is configured to perform one or more surgical tasks or procedures. In accordance with the present disclosure, various forms of interchangeable shaft assemblies may be effectively employed in connection with robotically controlled surgical systems. The term "housing" may encompass a housing or similar portion of a robotic system that houses or otherwise operably supports at least one drive system configured to generate and apply at least one control motion usable to actuate the interchangeable shaft assembly. The term "frame" may refer to a portion of a hand-held surgical instrument. The term "frame" may also refer to a portion of a robotically-controlled surgical instrument and/or a portion of a robotic system that may be used to operably control a surgical instrument. The interchangeable shaft assemblies may be employed WITH various robotic systems, INSTRUMENTS, components and methods disclosed in U.S. patent No. 9,072,535 entitled SURGICAL STAPLING instrument WITH ROTATABLE STAPLE deployment arrangement (SURGICAL STAPLING INSTRUMENTS WITH ROTATABLE stage deplayments), which is hereby incorporated by reference in its entirety.

Fig. 1 is a perspective view of a surgical instrument 10 having an interchangeable shaft assembly 200 operably coupled thereto according to one aspect of the present disclosure. The housing 12 includes an end effector 300, the end effector 300 including a surgical cutting and fastening device configured to operably support a surgical staple cartridge 304 therein. Housing 12 can be configured to be used in conjunction with an interchangeable shaft assembly that includes an end effector that is adapted to support different sizes and types of staple cartridges, having different shaft lengths, sizes, and types. Housing 12 may be employed with a variety of interchangeable shaft assemblies, including assemblies configured to apply other motions and forms of energy, such as Radio Frequency (RF) energy, ultrasonic energy, and/or motions, to end effector arrangements suitable for use in connection with various surgical applications and procedures. The end effector, shaft assembly, handle, surgical instrument, and/or surgical instrument system may utilize any suitable fastener or fasteners to fasten tissue. For example, a fastener cartridge including a plurality of fasteners removably stored therein can be removably inserted into and/or attached to an end effector of a shaft assembly.

The handle assembly 14 may include a pair of interconnectable handle housing segments 16, 18 that may be interconnected by screws, snap features, adhesives, or the like. The handle housing sections 16, 18 cooperate to form a pistol grip 19 that can be grasped and manipulated by a clinician. The handle assembly 14 operably supports a plurality of drive systems configured to generate and apply control motions to corresponding portions of an interchangeable shaft assembly operably attached thereto. A display may be provided under the cover 45.

Fig. 2 is an exploded assembly view of a portion of the surgical instrument 10 of fig. 1, according to one aspect of the present disclosure. The handle assembly 14 may include a frame 20 that operably supports a plurality of drive systems. The frame 20 operably supports a "first" or closure drive system 30, which "first" or closure drive system 30 can impart closing and opening motions to the interchangeable shaft assembly 200. The closure drive system 30 may include an actuator, such as a closure trigger 32, pivotally supported by the frame 20. The closure trigger 32 is pivotally coupled to the handle assembly 14 by a pivot pin 33 such that the closure trigger 32 can be manipulated by a clinician. The closure trigger 32 may pivot from a start or "unactuated" position to an "actuated" position and more specifically to a fully compressed or fully actuated position when the clinician grasps the pistol grip 19 of the handle assembly 14.

The handle assembly 14 and the frame 20 can operably support a firing drive system 80, the firing drive system 80 configured to apply firing motions to corresponding portions of the interchangeable shaft assembly attached thereto. The firing drive system 80 may employ an electric motor 82 located in the pistol grip portion 19 of the handle assembly 14. For example, the electric motor 82 may be a DC brushed motor with a maximum rotational speed of about 25,000 RPM. In other configurations, the motor may comprise a brushless motor, a cordless motor, a synchronous motor, a stepper motor, or any other suitable electric motor. The electric motor 82 may be powered by a power source 90, which power source 90 may include a removable power pack 92. The removable power pack 92 may include a proximal housing portion 94 configured to attach to a distal housing portion 96. The proximal housing portion 94 and the distal housing portion 96 are configured to operably support a plurality of batteries 98 therein. Batteries 98 may each include, for example, a Lithium Ion (LI) or other suitable battery. The distal housing portion 96 is configured for removable operative attachment to a control circuit board 100 operatively coupled to the electric motor 82. A number of batteries 98 connected in series may power the surgical instrument 10. The power source 90 may be replaceable and/or rechargeable. The display 45 located below the cover 43 is electrically coupled to the control circuit board 100. The cover 45 may be removed to expose the display 43.

The electric motor 82 may include a rotatable shaft (not shown) operably interfacing with a gear reducer assembly 84, the gear reducer assembly 84 being mounted in meshing engagement with a set or rack of drive teeth 122 on a longitudinally movable drive member 120. The longitudinally movable drive member 120 has a rack of drive teeth 122 formed thereon for engagement with the corresponding drive gear 86 of the gear reducer assembly 84.

In use, the polarity of the voltage provided by the power source 90 may operate the electric motor 82 in a clockwise direction, wherein the polarity of the voltage applied by the battery to the electric motor may be reversed to operate the electric motor 82 in a counterclockwise direction. When the electric motor 82 is rotated in one direction, the longitudinally movable drive member 120 will be driven axially in the distal direction "DD". When the electric motor 82 is driven in the opposite rotational direction, the longitudinally movable drive member 120 will be driven axially in the proximal direction "PD". The handle assembly 14 may include a switch that may be configured to reverse the polarity applied to the electric motor 82 by the power source 90. The handle assembly 14 may include a sensor configured to detect the position of the longitudinally movable drive member 120 and/or the direction of movement of the longitudinally movable drive member 120.

Actuation of the electric motor 82 is controlled by a firing trigger 130 pivotally supported on the handle assembly 14. The firing trigger 130 may be pivotable between an unactuated position and an actuated position.

Returning to fig. 1, the interchangeable shaft assembly 200 includes an end effector 300, the end effector 300 including an elongate channel 302 configured to operably support a surgical staple cartridge 304 therein. The end effector 300 may include an anvil 306, with the anvil 306 being pivotally supported relative to the elongate channel 302. The interchangeable shaft assembly 200 can include an articulation joint 270. The construction and operation of end effector 300 and ARTICULATION joint 270 is set forth in U.S. patent application publication No. 2014/0263541 entitled "ARTICULATABLE SURGICAL INSTRUMENT COMPLEMENTING AN ARTICULATION LOCK INCLUDING ARTICULATED LOCK," which is hereby incorporated by reference in its entirety. The interchangeable shaft assembly 200 can include a proximal housing or nozzle 201 comprised of nozzle portions 202, 203. The interchangeable shaft assembly 200 can include a closure tube 260 extending along a shaft axis SA, which closure tube 260 can be used to close and/or open the anvil 306 of the end effector 300.

Returning to FIG. 1, for example, in response to actuation of the closure trigger 32 in the manner described in the aforementioned referenced U.S. patent application publication No. 2014/0263541, the closure tube 260 is translated distally (direction "DD") to close the anvil 306. The anvil 306 is opened by translating the closure tube 260 proximally. In the anvil open position, the closure tube 260 is moved to its proximal position.

Fig. 3 is another exploded assembly view of portions of an interchangeable shaft assembly 200 according to one aspect of the present disclosure. The interchangeable shaft assembly 200 can include a firing member 220 supported for axial travel within the spine 210. The firing member 220 includes an intermediate firing shaft 222 configured to be attached to a distal cutting portion or knife bar 280. The firing member 220 may be referred to as a "second shaft" or "second shaft assembly". The intermediate firing shaft 222 can include a longitudinal slot 223 in a distal end, the longitudinal slot 223 configured to receive a tab 284 on a proximal end 282 of the knife bar 280. The longitudinal slot 223 and the proximal end 282 may be configured to allow relative movement therebetween and may include a slip joint 286. The slip joint 286 can allow the intermediate firing shaft 222 of the firing drive member 220 to articulate the end effector 300 about the articulation joint 270 without moving, or at least substantially without moving, the knife bar 280. Once the end effector 300 has been properly oriented, the intermediate firing shaft 222 can be advanced distally until the proximal side wall of the longitudinal slot 223 contacts the tab 284 to advance the knife bar 280 and fire a staple cartridge positioned within the channel 302. The spine 210 has an elongated opening or window 213 therein to facilitate assembly and insertion of the intermediate firing shaft 222 into the spine 210. Once the intermediate firing shaft 222 has been inserted into the shaft frame, the top frame segment 215 may be engaged with the shaft frame 212 to enclose the intermediate firing shaft 222 and knife bar 280 therein. Operation of the firing member 220 can be seen in U.S. patent application publication No. 2014/0263541. The spine 210 may be configured to slidably support a firing member 220 and a closure tube 260 that extends around the spine 210. The spine 210 slidably supports an articulation driver 230.

The interchangeable shaft assembly 200 can include a clutch assembly 400, the clutch assembly 400 configured to selectively and releasably couple the articulation driver 230 to the firing member 220. The clutch assembly 400 includes a lock collar or lock sleeve 402 positioned about the firing member 220, wherein the lock sleeve 402 is rotatable between an engaged position, wherein the lock sleeve 402 couples the articulation driver 230 to the firing member 220, and a disengaged position, wherein the articulation driver 230 is not operably coupled to the firing member 220. When the locking sleeve 402 is in the engaged position, distal movement of the firing member 220 can move the articulation driver 230 distally, and correspondingly, proximal movement of the firing member 220 can move the articulation driver 230 proximally. When the locking sleeve 402 is in the disengaged position, movement of the firing member 220 is not transmitted to the articulation driver 230, and thus, the firing member 220 may move independently of the articulation driver 230. The nozzle 201 may be used to operably engage and disengage an articulation drive system from a firing drive system in a variety of ways as described in U.S. patent application publication No. 2014/0263541.

Interchangeable shaft assembly 200 can include a slip ring assembly 600, for example, slip ring assembly 600 can be configured to conduct electrical power to and/or from end effector 300, and/or transmit signals to and/or receive signals from end effector 300. Slip ring assembly 600 may include a proximal connector flange 604 and a distal connector flange 601 positioned within slots defined in nozzle portions 202, 203. The proximal connector flange 604 may comprise a first face and the distal connector flange 601 may comprise a second face positioned adjacent to and movable relative to the first face. The distal connector flange 601 is rotatable relative to the proximal connector flange 604 about an axis SA-SA (FIG. 1). The proximal connector flange 604 may include a plurality of concentric or at least substantially concentric conductors 602 defined in a first face thereof. The connector 607 may be mounted on the proximal face of the distal connector flange 601 and may have a plurality of contacts, each of which corresponds to and is in electrical contact with one of the conductors 602. Such a configuration allows for relative rotation between the proximal connector flange 604 and the distal connector flange 601 while maintaining electrical contact therebetween. For example, the proximal connector flange 604 may include an electrical connector 606, which electrical connector 606 may place the conductor 602 in signal communication with the shaft circuit board. In at least one example, a wire harness including a plurality of conductors may extend between the electrical connector 606 and the shaft circuit board. The electrical connector 606 may extend proximally through a connector opening defined in the chassis mounting flange. U.S. patent application publication 2014/0263551 entitled "STAPLE CARTRIDGE TISSUETHICKNESS SENSOR SYSTEM" is hereby incorporated by reference in its entirety. U.S. patent application publication 2014/0263552 entitled "STAPLE CARTRIDGE TISSUE THICKNESS SENSOR SYSTEM" is hereby incorporated by reference in its entirety. More details regarding slip ring assembly 600 may be found in U.S. patent application publication 2014/0263541.

The interchangeable shaft assembly 200 can include a proximal portion that can be fixedly mounted to the handle assembly 14, and a distal portion that is rotatable about a longitudinal axis. The rotatable distal shaft portion may be rotated relative to the proximal portion about the slip ring assembly 600. The distal connector flange 601 of the slip ring assembly 600 may be positioned within the rotatable distal shaft portion.

Fig. 4 is an exploded view of one aspect of the end effector 300 of the surgical instrument 10 of fig. 1, according to one aspect of the present disclosure. The end effector 300 may include an anvil 306 and a surgical staple cartridge 304. The anvil 306 may be coupled to the elongate channel 302. Apertures 199 may be defined in the elongate channel 302 to receive pins 152 extending from the anvil 306 to allow the anvil 306 to pivot from an open position to a closed position relative to the elongate channel 302 and the surgical staple cartridge 304. The firing bar 172 is configured to longitudinally translate into the end effector 300. The firing bar 172 may be constructed from one solid section or may comprise a laminate material comprising a stack of steel plates. The firing bar 172 includes an I-beam 178 and a cutting edge 182 at a distal end thereof. Distal protruding ends of the firing bar 172 may be attached to the I-beam 178 to assist in spacing the anvil 306 from the surgical staple cartridge 304 positioned in the elongate channel 302 when the anvil 306 is in the closed position. The I-beam 178 may include a sharp cutting edge 182 to sever tissue as the I-beam 178 is advanced distally through the firing bar 172. In operation, the I-beam 178 may alternatively fire the surgical staple cartridge 304. The surgical staple cartridge 304 can comprise a molded cartridge body 194 that holds a plurality of staples 191 disposed on staple drivers 192 located in respective upwardly opening staple cavities 195. The wedge sled 190 is driven distally by the I-beam 178 to slide over the cartridge tray 196 of the surgical staple cartridge 304. The wedge sled 190 cams staple drivers 192 upward to extrude staples 191 into deforming contact with the anvil 306 while the cutting edge 182 of the I-beam 178 severs the clamped tissue.

The I-beam 178 may include an upper pin 180 that engages the anvil 306 during firing. The I-beam 178 can include intermediate pins 184 and feet 186 to engage portions of the cartridge body 194, the cartridge tray 196, and the elongate channel 302. When the surgical staple cartridge 304 is positioned within the elongate channel 302, the slot 193 defined in the cartridge body 194 can be aligned with the longitudinal slot 197 defined in the cartridge tray 196 and the slot 189 defined in the elongate channel 302. In use, the I-beam 178 can be slid through the aligned longitudinal slots 193, 197, and 189, as shown in fig. 4, wherein the foot 186 of the I-beam 178 can engage a groove extending along the bottom surface of the elongate channel 302 along the length of the slot 189, the middle pin 184 can engage the top surface of the cartridge tray 196 along the length of the longitudinal slot 197, and the upper pin 180 can engage the anvil 306. The I-beam 178 can separate or limit relative movement between the anvil 306 and the surgical staple cartridge 304 as the firing bar 172 is advanced distally to fire the staples from the surgical staple cartridge 304 and/or to incise tissue trapped between the anvil 306 and the surgical staple cartridge 304. The firing bar 172 and the I-beam 178 can be retracted proximally, thereby allowing the anvil 306 to be opened to release the two stapled and severed tissue portions.

Fig. 5A-5B are block diagrams of control circuitry 700 of the surgical instrument 10 of fig. 1 spanning two drawings in accordance with an aspect of the present disclosure. Referring primarily to fig. 5A-5B, the handle assembly 702 can include a motor 714, the motor 714 can be controlled by a motor driver 715 and can be used by a firing system of the surgical instrument 10. In various forms, the motor 714 may be a DC brushed driving motor with a maximum rotational speed of about 25,000 RPM. In other arrangements, the motor 714 may include a brushless motor, a cordless motor, a synchronous motor, a stepper motor, or any other suitable electric motor. The motor driver 715 may include, for example, an H-bridge driver including a Field Effect Transistor (FET) 719. The motor 714 may be powered by a power assembly 706, which power assembly 706 is releasably mounted to the handle assembly 200 for providing control power to the surgical instrument 10. The power assembly 706 may include a battery that may include a plurality of battery cells connected in series that may be used as a power source to power the surgical instrument 10. In some cases, the battery cells of power component 706 may be replaceable and/or rechargeable. In at least one example, the battery cell may be a lithium ion battery that is detachably coupleable to the power assembly 706.

Shaft assembly 704 can include a shaft assembly controller 722 that can communicate with safety and power management controller 716 through an interface when shaft assembly 704 and power assembly 706 are coupled to handle assembly 702. For example, the interface can include a first interface portion 725 and a second interface portion 727, wherein the first interface portion 725 can include one or more electrical connectors for coupling engagement with corresponding shaft assembly electrical connectors and the second interface portion 727 can include one or more electrical connectors for coupling engagement with corresponding power assembly electrical connectors, thereby allowing electrical communication between the shaft assembly controller 722 and the power management controller 716 when the shaft assembly 704 and the power assembly 706 are coupled to the handle assembly 702. One or more communication signals may be transmitted over the interface to communicate one or more power requirements of the attached interchangeable shaft assembly 704 to the power management controller 716. In response, power management controller may adjust the power output of the battery of power assembly 706 as a function of the power requirements of attachment shaft assembly 704, as described in more detail below. The connector may include switches that may be activated after the handle assembly 702 is mechanically coupled to the shaft assembly 704 and/or power assembly 706 to allow electrical communication between the shaft assembly controller 722 and the power management controller 716.

For example, the interface may facilitate the transmission of one or more communication signals between the power management controller 716 and the shaft assembly controller 722 by routing such communication signals through the main controller 717 located in the handle assembly 702. In other instances, when the shaft assembly 704 and the power assembly 706 are coupled to the handle assembly 702, the interface may facilitate a direct communication link between the power management controller 716 and the shaft assembly controller 722 through the handle assembly 702.

The main controller 717 may be any single-core or multi-core processor, such as those sold under the trade name "ARM Cortex" by Texas instruments, Inc. (Texas instruments). In one aspect, the master controller 717 may be, for example, an LM4F230H5QR ARM Cortex-M4F processor core available from Texas instruments, Inc., which includes: 256KB of single cycle flash or other non-volatile memory (up to 40MHz) on-chip memory, prefetch buffers to improve performance beyond 40MHz, 32KB of single cycle Serial Random Access Memory (SRAM), load with Internal Read Only Memory (ROM) in software, Electrically Erasable Programmable Read Only Memory (EEPROM) in 2KB, one or more Pulse Width Modulation (PWM) modules, one or more Quadrature Encoder Input (QEI) analog, one or more 12-bit analog-to-digital converters (ADCs) with 12 analog input channels, and other features readily available.

The safety controller may be a safety controller platform comprising two controller-based families, such as TMS570 and RM4x, also known by texas instruments under the trade name "Hercules ARM Cortex R4". The safety controller can be configured to be dedicated to IEC 61508 and ISO 26262 safety critical applications, among others, to provide advanced integrated safety features while delivering scalable performance, connectivity, and memory options.

The power component 706 may include a power management circuit that may include a power management controller 716, a power modulator 738, and a current sensing circuit 736. When shaft assembly 704 and power assembly 706 are coupled to handle assembly 702, the power management circuitry may be configured to be capable of adjusting the power output of the battery based on the power requirements of shaft assembly 704. The power management controller 716 may be programmed to control a power modulator 738 of the power output of the power component 706, and a current sensing circuit 736 may be used to monitor the power output of the power component 706 to provide feedback to the power management controller 716 regarding the power output of the battery so that the power management controller 716 may adjust the power output of the power component 706 to maintain a desired output. Power management controller 716 and/or shaft assembly controller 722 may each include one or more processors and/or memory units that may store a plurality of software modules.

The surgical instrument 10 (fig. 1-4) may include an output device 742, and the output device 742 may include a device for providing sensory feedback to a user. Such devices may include, for example, visual feedback devices (e.g., LCD display screens, LED indicators), audio feedback devices (e.g., speakers, buzzers), or tactile feedback devices (e.g., haptic actuators). In some cases, the output device 742 can include a display 743, which display 743 can be included in the handle assembly 702. The shaft assembly controller 722 and/or the power management controller 716 can provide feedback to a user of the surgical instrument 10 via an output device 742. The interface may be configured to connect the shaft assembly controller 722 and/or the power management controller 716 to an output device 742. Alternatively, the output device 742 may be integrated with the power component 706. In such instances, when the shaft assembly 704 is coupled to the handle assembly 702, communication between the output device 742 and the shaft assembly controller 722 may be achieved through an interface.

The control circuit 700 includes a circuit segment configured to control the operation of the powered surgical instrument 10. The safety controller section (section 1) includes a safety controller and a main controller 717 section (section 2). The safety controller and/or the main controller 717 is configured to be able to interact with one or more additional circuit segments, such as an acceleration segment, a display segment, a shaft segment, an encoder segment, a motor segment, and a power segment. Each of the circuit segments may be coupled to a safety controller and/or a main controller 717. The main controller 717 is also coupled to a flash memory. The main controller 717 also includes a serial communication interface. The main controller 717 includes a plurality of input devices coupled to, for example, one or more circuit segments, a battery, and/or a plurality of switches. The segmented circuit may be implemented by any suitable circuit, such as a Printed Circuit Board Assembly (PCBA) within the powered surgical instrument 10. It is to be understood that the term "processor" as used herein includes any microprocessor, processor, microcontroller, controller or other basic computing device that combines the functions of a computer's Central Processing Unit (CPU) onto one integrated circuit or at most a few integrated circuits. The main controller 717 is a multipurpose programmable device that receives digital data as input, processes the input according to instructions stored in its memory, and then provides the result as output. Because the processor has internal memory, it is an example of sequential digital logic. The control circuit 700 may be configured to implement one or more of the processes described herein.

The acceleration segment (segment 3) includes an accelerometer. The accelerometer is configured to detect movement or acceleration of the powered surgical instrument 10. Inputs from the accelerometer can be used to transition to and from sleep mode, identify the orientation of the powered surgical instrument, and/or identify when the surgical instrument has been dropped. In some examples, the acceleration segment is coupled to a safety controller and/or a main controller 717.

The display segment (segment 4) includes a display connector coupled to a main controller 717. The display connector couples the main controller 717 to the display through one or more integrated circuit drivers for the display. The integrated circuit driver of the display may be integrated with the display and/or may be located separately from the display. The display may include any suitable display, such as an Organic Light Emitting Diode (OLED) display, a Liquid Crystal Display (LCD), and/or any other suitable display. In some examples, the display segment is coupled to a safety controller.

The shaft segment (segment 5) includes controls for coupling to the interchangeable shaft assembly 200 (fig. 1 and 3) of the surgical instrument 10 (fig. 1-4) and/or one or more controls for coupling to the end effector 300 of the interchangeable shaft assembly 200. The shaft section includes a shaft connector configured to couple the main controller 717 to the shaft PCBA. The shaft PCBA includes a low power microcontroller having a Ferroelectric Random Access Memory (FRAM), an articulation switch, a shaft release hall effect switch, and a shaft PCBA EEPROM. The shaft PCBA EEPROM includes one or more parameters, routines and/or programs that are specific to the interchangeable shaft assembly 200 and/or the shaft PCBA. The shaft PCBA may be coupled to the interchangeable shaft assembly 200 and/or integral with the surgical instrument 10. In some examples, the shaft segment includes a second shaft EEPROM. The second shaft EEPROM includes a plurality of algorithms, routines, parameters, and/or other data corresponding to one or more shaft assemblies 200 and/or end effectors 300 that may interface with the powered surgical instrument 10.

The position encoder section (section 6) comprises one or more magnetic angular rotary position encoders. The one or more magnetic angular rotational position encoders are configured to identify the rotational position of the motor 714, interchangeable shaft assembly 200 (fig. 1 and 3), and/or end effector 300 of the surgical instrument 10 (fig. 1-4). In some examples, a magnetic angular rotational position encoder may be coupled to the safety controller and/or the main controller 717.

The motor circuit section (section 7) includes a motor 714 configured to control movement of the powered surgical instrument 10 (fig. 1-4). The motor 714 is coupled to the main microcontroller processor 717 through an H-bridge driver comprising one or more H-bridge Field Effect Transistors (FETs) and a motor controller. The H-bridge driver is also coupled to the safety controller. A motor current sensor is coupled in series with the motor for measuring a current draw of the motor. The motor current sensor is in signal communication with the main controller 717 and/or the safety controller. In some examples, the motor 714 is coupled to a motor electromagnetic interference (EMI) filter.

The motor controller controls the first motor flag and the second motor flag to indicate the state and position of the motor 714 to the main controller 717. The main controller 717 provides a Pulse Width Modulation (PWM) high signal, a PWM low signal, a direction signal, a synchronization signal, and a motor reset signal to the motor controller through the buffer. The power segment is configured to be capable of providing a segment voltage to each of the circuit segments.

The power section (section 8) includes a battery coupled to a safety controller, a main controller 717 and additional circuit sections. The battery is coupled to the segmented circuit by a battery connector and a current sensor. The current sensor is configured to be able to measure the total current consumption of the segmented circuit. In some examples, the one or more voltage converters are configured to be capable of providing a predetermined voltage value to the one or more circuit segments. For example, in some examples, the segmented circuit may include a 3.3 volt voltage converter and/or a 5 volt voltage converter. The boost converter is configured to be able to provide a boost voltage of up to a predetermined amount, such as up to 13V. The boost converter is configured to be able to provide additional voltage and/or current during power intensive operations and to be able to prevent a reduced voltage condition or a low power condition.

A plurality of switches are coupled to the safety controller and/or the main controller 717. The switch may be configured to control operation of the surgical instrument 10 (fig. 1-4), the segmented circuit, and/or indicate a status of the surgical instrument 10. The panic door switch and the hall effect switch for panic are configured to be capable of indicating the status of the panic door. A plurality of articulation switches, such as a left articulation switch, a left right articulation switch, a left center-to-center articulation switch, a right left articulation switch, a right center-to-right articulation switch, and a right center-to-center articulation switch, are configured to control articulation of the interchangeable shaft assembly 200 (fig. 1 and 3) and/or the end effector 300 (fig. 1 and 4). The left hand and right hand commutation switches are coupled to a main controller 717. The left switches (including a left articulation switch, a left right articulation switch, a left center articulation switch, and a left reversing switch) are coupled to the main controller 717 through a left flex connector. The right switches (including the right left articulation switch, the right articulation switch, the right center articulation switch, and the right reversing switch) are coupled to the master controller 717 through a right flex connector. The cocking switch, clamp release switch, and shaft engagement switch are linked to the main controller 717.

Any suitable mechanical switch, electromechanical switch, or solid state switch may be used in any combination to implement the plurality of switches. For example, the switch may be a limit switch operated by movement of a component associated with the surgical instrument 10 (fig. 1-4) or the presence of an object. Such switches may be used to control various functions associated with the surgical instrument 10. Limit switches are electromechanical devices consisting of an actuator mechanically connected to a set of contacts. When an object comes into contact with the actuator, the device operates the contacts to make or break the electrical connection. The limit switch is durable, simple and convenient to install, reliable in operation and suitable for various applications and environments. The limit switches can determine the presence or absence, the passage, the location, and the end of travel of the object. In other embodiments, the switches may be solid state switches that operate under the influence of a magnetic field, such as hall effect devices, Magnetoresistive (MR) devices, Giant Magnetoresistive (GMR) devices, magnetometers, and others. In other embodiments, the switch may be a solid state switch that operates under the influence of light, such as an optical sensor, an infrared sensor, an ultraviolet sensor, and others. Likewise, the switches may be solid state devices such as transistors (e.g., FETs, junction FETs, metal oxide semiconductor FETs (mosfets), bipolar transistors, etc.). Other switches may include wireless switches, ultrasonic switches, accelerometers, inertial sensors, and others.

Fig. 6 is a block diagram of a control circuit 700 of the surgical instrument of fig. 1 illustrating a handle assembly 702 and a power assembly 706 and an interface between the handle assembly 702 and an interchangeable shaft assembly 704 according to one aspect of the present disclosure. The handle assembly 702 may include a main controller 717, a shaft assembly connector 726, and a power assembly connector 730. The power component 706 may include a power component connector 732, a power management circuit 734, the power management circuit 734 may include a power management controller 716, a power modulator 738, and a current sensing circuit 736. The shaft assembly connectors 730, 732 form an interface 727. Power management circuit 734 may be configured to adjust the power output of battery 707 based on the power requirements of interchangeable shaft assembly 704 when interchangeable shaft assembly 200 and power assembly 706 are coupled to handle assembly 702. The power management controller 716 may be programmed to control the power modulator 738 to adjust the power output of the power component 706, and the current sensing circuit 736 may be used to monitor the power output of the power component 706 to provide feedback to the power management controller 716 regarding the power output of the battery 707, such that the power management controller 716 may adjust the power output of the power component 706 to maintain a desired output. The shaft assembly 704 includes a shaft processor 719 coupled to a non-volatile memory 721 and a shaft assembly connector 728 to electrically couple the shaft assembly 704 to the handle assembly 702. The shaft assembly connectors 726, 728 form an interface 725. The main controller 717, the axis processor 719, and/or the power management controller 716 may be configured to be capable of implementing one or more of the processes described herein.

The surgical instrument 10 (fig. 1-4) may include an output device 742 to provide sensory feedback to the user. Such devices may include visual feedback devices (e.g., LCD display screens, LED indicators), audible feedback devices (e.g., speakers, buzzers), or tactile feedback devices (e.g., haptic actuators). In some cases, the output device 742 can include a display 743, which display 743 can be included in the handle assembly 702. The shaft assembly controller 722 and/or the power management controller 716 can provide feedback to a user of the surgical instrument 10 via an output device 742. The interface 727 may be configured to enable connection of the shaft assembly controller 722 and/or the power management controller 716 to the output device 742. The output device 742 may be integrated with the power component 706. When the interchangeable shaft assembly 704 is coupled to the handle assembly 702, communication between the output device 742 and the shaft assembly controller 722 can be accomplished through the interface 725. Having described the control circuit 700 (fig. 5A-5B and 6) for controlling the operation of the surgical instrument 10 (fig. 1-4), the present disclosure now turns to various configurations of the surgical instrument 10 (fig. 1-4) and the control circuit 700.

Fig. 7 shows a control circuit 800, the control circuit 800 configured to control aspects of the surgical instrument 10 (fig. 1-4) according to one aspect of the present disclosure. The control circuitry 800 may be configured to implement various processes described herein. The control circuit 800 may include a controller including one or more processors 802 (e.g., microprocessors, microcontrollers) coupled to at least one memory circuit 804. The memory circuit 804 stores machine-executable instructions that, when executed by the processor 802, cause the processor 802 to execute machine instructions to implement the various processes described herein. The processor 802 may be any of a variety of single-core or multi-core processors known in the art. The memory circuit 804 may include volatile storage media and non-volatile storage media. The processor 802 may include an instruction processing unit 806 and an arithmetic unit 808. The instruction processing unit may be configured to be able to receive instructions from the memory circuit 804.

Fig. 8 illustrates a combinational logic circuit 810, the combinational logic circuit 810 configured to control aspects of a surgical instrument 10 (fig. 1-4) according to an aspect of the present disclosure. The combinational logic circuit 810 may be configured to implement the various processes described herein. The circuit 810 may comprise a finite state machine including combinatorial logic circuitry 812 configured to receive data associated with the surgical instrument 10 at an input 814, process the data through the combinatorial logic 812, and provide an output 816.

Fig. 9 illustrates a sequential logic circuit 820, the sequential logic circuit 820 configured to control aspects of the surgical instrument 10 (fig. 1-4) according to one aspect of the present disclosure. Sequential logic 820 or combinational logic 822 may be configured to implement the various processes described herein. Circuitry 820 may include a finite state machine. The sequential logic circuit 820 may include, for example, a combinational logic circuit 822, at least one memory circuit 824, and a clock 829. The at least one memory circuit 820 may store a current state of the finite state machine. In some cases, sequential logic circuit 820 may be synchronous or asynchronous. The combinational logic circuit 822 is configured to receive data associated with the surgical instrument 10 from the inputs 826, process the data through the combinational logic circuit 822 and provide the outputs 828. In other aspects, the circuitry may comprise a combination of the processor 802 and a finite state machine to implement the various processes herein. In other aspects, the finite state machine may comprise a combination of combinational logic circuit 810 and sequential logic circuit 820.

Aspects may be implemented as an article of manufacture. An article of manufacture may comprise a computer-readable storage medium arranged to store logic, instructions, and/or data for performing various operations of one or more aspects. For example, an article of manufacture may comprise a magnetic disk, optical disk, flash memory, or firmware, including computer program instructions adapted to be executed by a general-purpose processor or a special-purpose processor.

Fig. 10 is a schematic diagram of an absolute positioning system 1100 of the surgical instrument 10 (fig. 1-4) according to one aspect of the present disclosure, wherein the absolute positioning system 1100 includes a controlled motor drive circuit arrangement that includes a sensor arrangement 1102. The sensor arrangement 1102 for the absolute positioning system 1100 provides a unique position signal corresponding to the position of the displacement member 1111. Turning briefly to fig. 2-4, in one aspect, displacement member 1111 represents a longitudinally movable drive member 120 (fig. 2) that includes a rack of drive teeth 122 for meshing engagement with a corresponding drive gear 86 of gear reducer assembly 84. In other aspects, the displacement member 1111 represents a firing member 220 (fig. 3), which firing member 220 can be adapted and configured as a rack including drive teeth. In yet another aspect, the displacement member 1111 represents the firing bar 172 (FIG. 4) or the I-beam 178 (FIG. 4), each of which may be adapted and configured as a rack including drive teeth. Accordingly, as used herein, the term displacement member is used to generally refer to any movable member of the surgical instrument 10 (such as the drive member 120, the firing member 220, the firing bar 172, the I-beam 178, or any displaceable element). In one aspect, the longitudinally movable drive member 120 is coupled to the firing member 220, the firing bar 172, and the I-beam 178. Thus, absolute positioning system 1100 may actually track the linear displacement of I-beam 178 by tracking the linear displacement of longitudinally movable drive member 120. In various other aspects, displacement member 1111 may be coupled to any sensor suitable for measuring linear displacement. Thus, the longitudinally movable drive member 120, the firing member 220, the firing bar 172, or the I-beam 178, or a combination thereof, may be coupled to any suitable linear displacement sensor. The linear displacement sensor may comprise a contact displacement sensor or a non-contact displacement sensor. The linear displacement sensor may comprise a Linear Variable Differential Transformer (LVDT), a Differential Variable Reluctance Transducer (DVRT), a sliding potentiometer, a magnetic sensing system comprising a movable magnet and a series of linearly arranged hall effect sensors, a magnetic sensing system comprising a fixed magnet and a series of movable linearly arranged hall effect sensors, an optical sensing system comprising a movable light source and a series of linearly arranged photodiodes or photodetectors, an optical sensing system comprising a fixed light source and a series of movable linearly arranged photodiodes or photodetectors, or any combination thereof.

The electric motor 1120 may include a rotatable shaft 1116 that operably interfaces with a gear assembly 1114, the gear assembly 1114 being mounted in meshing engagement with a set or rack of drive teeth on the displacement member 1111. The sensor element 1126 may be operably coupled to the gear assembly 1114 such that a single rotation of the sensor element 1126 corresponds to some linear longitudinal translation of the displacement member 1111. The arrangement of the transmission and sensor 1118 may be connected to a linear actuator via a rack and pinion arrangement, or to a rotary actuator via a spur gear or other connection. A power source 1129 provides power to the absolute positioning system 1100 and an output indicator 1128 may display the output of the absolute positioning system 1100. In fig. 2, displacement member 1111 represents a longitudinally movable drive member 120, the longitudinally movable drive member 120 including a rack of drive teeth 122 formed thereon for meshing engagement with a corresponding drive gear 86 of gear reducer assembly 84. The displacement member 1111 represents the longitudinally movable firing member 220, the firing bar 172, the I-beam 178, or a combination thereof.

A single rotation of sensor element 1126 associated with position sensor 1112 is equivalent to a longitudinal linear displacement d1 of displacement member 1111, where d1 is the longitudinal linear distance that displacement member 1111 moves from point "a" to point "b" after a single rotation of sensor element 1126 coupled to displacement member 1111. Sensor arrangement 1102 may be connected via a gear reduction that causes position sensor 1112 to complete one or more rotations for a full stroke of displacement member 1111. Position sensor 1112 may complete multiple rotations for a full stroke of displacement member 1111.

A series of switches 1122 a-1122 n (where n is an integer greater than one) may be employed alone or in conjunction with gear reduction to provide unique position signals for more than one rotation of position sensor 1112. The state of the switches 1122 a-1122 n is fed back to the controller 1104, and the controller 1104 applies logic to determine a unique position signal corresponding to the longitudinal linear displacement d1+ d2+ … dn of the displacement member 1111. The output 1124 of the position sensor 1112 is provided to the controller 1104. The position sensor 1112 of the sensor arrangement 1102 may include a magnetic sensor, an analog rotation sensor (e.g., a potentiometer), an array of analog hall effect elements that output a unique combination of position signals or values.

Absolute positioning system 1100 provides the absolute position of displacement member 1111 upon instrument power up, and does not retract or advance displacement member 1111 to a reset (clear or home) position as may be required by conventional rotary encoders, which simply count the number of forward or backward steps taken by motor 1120 to infer the position of the device actuator, drive rod, knife, etc.

The controller 1104 may be programmed to perform various functions, such as precise control of the tool and the speed and position of the articulation system. In one aspect, the controller 1104 includes a processor 1108 and a memory 1106. The electric motor 1120 may be a brushed DC motor having a gearbox and mechanical linkage to an articulation or knife system. In one aspect, the motor drive 1110 can be a3941 available from Allegro Microsystems, Inc. Other motor drives can be readily substituted for use in absolute positioning system 1100. More detailed description of the absolute positioning system 1100 is described in U.S. patent application No. 15/130,590 entitled "system and method for CONTROLLING a SURGICAL stapling and severing INSTRUMENT (SYSTEMS AND method for CONTROLLING a SURGICAL stapling a SURGICAL STAPLING AND CUTTING INSTRUMENT," filed on 15.4.2016, the entire disclosure of which is incorporated herein by reference.

The controller 1104 may be programmed to provide precise control of the speed and position of the displacement member 1111 and the articulation system. The controller 1104 can be configured to calculate a response in software of the controller 1104. The calculated response is compared to the measured response of the actual system to obtain an "observed" response, which is used for the actual feedback decision. The observed response is a favorable tuning value that equalizes the smooth continuous nature of the simulated response with the measured response, which can sense external influences on the system.

The absolute positioning system 1100 may include and/or may be programmed to implement feedback controllers such as PID, state feedback, and adaptive controllers. The power source 1129 converts the signal from the feedback controller into a physical input, in this case a voltage, to the system. Other examples include Pulse Width Modulation (PWM) of voltage, current, and force. In addition to the position measured by position sensor 1112, other sensor(s) 1118 may be provided to measure physical parameters of the physical system. In a digital signal processing system, the absolute positioning system 1100 is coupled to a digital data acquisition system, wherein the output of the absolute positioning system 1100 will have a limited resolution and sampling frequency. The absolute positioning system 1100 may include comparison and combination circuitry to combine the calculated response with the measured response using an algorithm (such as a weighted average and a theoretical control loop) that drives the calculated response toward the measured response. The calculated response of the physical system takes into account characteristics such as mass, inertia, viscous friction, inductive resistance to predict the state and output of the physical system by knowing the inputs. The controller 1104 may be the control circuit 700 (fig. 5A-5B).

The driver 1110 may be a3941 available from Allegro microsystems. The a3941 driver 1110 is a full-bridge controller for use with an external N-channel power Metal Oxide Semiconductor Field Effect Transistor (MOSFET) specifically designed for inductive loads, such as brushed DC motors. Driver 1110 includes a unique charge pump voltage regulator that provides full (>10V) gate drive for battery voltages as low as 7V and allows a3941 to operate at reduced gate drive as low as 5.5V. A bootstrap capacitor may be used to provide the above-mentioned battery supply voltage required for the N-channel MOSFET. The internal charge pump of the high-side drive allows for direct current (100% duty cycle) operation. The full bridge may be driven in fast decay mode or slow decay mode using diodes or synchronous rectification. In slow decay mode, current recirculation can pass through either the high-side or low-side FETs. The power FET is protected from breakdown by a resistor adjustable dead time. The integrated diagnostics provide an indication of undervoltage, overheating, and power bridge faults, and may be configured to protect the power MOSFETs under most short circuit conditions. Other motor drives can be readily substituted for use in absolute positioning system 1100.

Having described a general architecture for implementing aspects of the absolute positioning system 1100 with respect to the sensor arrangement 1102, the present disclosure now turns to fig. 11 and 12 to obtain a description of one aspect of the sensor arrangement 1102 of the absolute positioning system 1100. FIG. 11 is an exploded perspective view of a sensor structure 1102 of an absolute positioning system 1100 showing the relative alignment of elements of a circuit 1205 and the sensor structure 1102, according to one aspect. The sensor arrangement 1102 of the absolute positioning system 1100 comprises a position sensor 1200, a magnet 1202 sensor element, a magnet holder 1204 that rotates once per full stroke of the displacement member 1111, and a gear assembly 1206 that provides a gear reduction. Referring briefly to fig. 2, displacement member 1111 represents a longitudinally movable drive member 120, the longitudinally movable drive member 120 including a rack of drive teeth 122 for meshing engagement with a corresponding drive gear 86 of gear reducer assembly 84. Returning to fig. 11, structural elements, such as a bracket 1216, are provided to support the gear assembly 1206, magnet holder 1204, and magnet 1202. The position sensor 1200 includes a magnetic sensing element (such as a hall element) and is placed in proximity to the magnet 1202. As the magnet 1202 rotates, the magnetic sensing element of the position sensor 1200 determines the absolute angular position of the magnet 1202 over one revolution.

The sensor arrangement 1102 may include any number of magnetic sensing elements, such as magnetic sensors that are classified according to whether they measure the total magnetic field of the magnetic field or vector components of the magnetic field. The techniques for producing the two types of magnetic sensors described above encompass a number of aspects of physics and electronics. Technologies for magnetic field sensing include detection coils, flux gates, optical pumps, nuclear spins, superconducting quantum interferometers (SQUIDs), hall effects, anisotropic magnetoresistance, giant magnetoresistance, magnetic tunnel junctions, giant magnetoimpedances, magnetostrictive/piezoelectric composites, magnetodiodes, magnetotransistors, optical fibers, magneto-optical, and magnetic sensors based on micro-electromechanical systems, among others.

The gear assembly includes a first gear 1208 and a second gear 1210 in meshing engagement to provide a 3: 1 gear ratio connection. Third gear 1212 rotates about shaft 1214. Third gear 1212 is in meshing engagement with displacement member 1111 (or 120 shown in fig. 2) and rotates in a first direction when displacement member 1111 is advanced in distal direction D and rotates in a second direction when displacement member 1111 is retracted in proximal direction P. The second gear 1210 also rotates about the axis 1214, and thus, rotation of the second gear 1210 about the axis 1214 corresponds to longitudinal translation of the displacement member 1111. Thus, one full stroke of displacement member 1111 in the distal direction D or the proximal direction P corresponds to three rotations of second gear 1210 and a single rotation of first gear 1208. Since magnet holder 1204 is coupled to first gear 1208, magnet holder 1204 makes one full rotation with each full stroke of displacement member 1111.

The position sensor 1200 is supported by a position sensor holder 1218 and is precisely aligned with a magnet 1202 rotating below within the magnet holder 1204, which defines a bore 1220 adapted to contain the position sensor 1200. The clamp is coupled to bracket 1216 and circuit 1205 and remains stationary as magnet 1202 rotates with magnet holder 1204. A hub 1222 is provided to mate with the first gear 1208 and the magnet holder 1204. Also shown are a second gear 1210 and a third gear 1212 coupled to the shaft 1214.

Fig. 12 is a diagram of a position sensor 1200 of an absolute positioning system 1100, the absolute positioning system 1100 including a magnetic rotary absolute positioning system, according to one aspect of the present disclosure. The position sensor 1200 may be implemented AS an AS5055EQFT monolithic magnetic rotary position sensor, available from Austria Microsystems, AG. The position sensor 1200 interfaces with a controller 1104 to provide an absolute positioning system 1100. The position sensor 1200 is a low voltage and low power component and includes four hall effect elements 1228A, 1228B, 1228C, 1228D in a region 1230 of the position sensor 1200 located above the magnet 1202 (fig. 15 and 16). A high resolution ADC1232 and an intelligent power management controller 1238 are also provided on the chip. CORDIC processor 1236 (for coordinate rotation Digital Computer (coordinate rotation Digital Computer)), also known as the bitwise and Volder algorithms, is provided to perform simple and efficient algorithms to compute hyperbolic and trigonometric functions, requiring only addition, subtraction, bit shifting and table lookup operations. The angular position, alarm bits, and magnetic field information are transmitted to the controller 1104 over a standard serial communication interface, such as SPI interface 1234. The position sensor 1200 provides 12 or 14 bit resolution. The position sensor 1200 may be an AS5055 chip provided in a small QFN 16-pin 4 × 4 × 0.85mm package.

The hall effect elements 1228A, 1228B, 1228C, 1228D are located directly above the rotating magnet 1202 (fig. 11). The hall effect is a well-known effect and will not be described in detail herein for convenience, however, in general, the hall effect produces a voltage difference (hall voltage) across an electrical conductor with a current in the conductor and a magnetic field perpendicular to the current. The hall coefficient is defined as the ratio of the induced electric field to the product of the current density and the applied magnetic field. It is a property of the material from which the conductor is made, as its value depends on the type, number and properties of the charge carriers that make up the current. In the AS5055 position sensor 1200, the hall effect elements 1228A, 1228B, 1228C, 1228D can generate a voltage signal that indicates the absolute position of the magnet 1202 in terms of the angle of the magnet 1202 after a single rotation. This value of the angle, which is a unique position signal, is calculated by CORDIC processor 1236 and stored on board the AS5055 position sensor 1200 in a register or memory. In various techniques, such as upon power up or upon request by the controller 1104, the controller 1104 is provided with a value of the angle that indicates the position of the magnet 1202 over one rotation.

The AS5055 position sensor 1200 requires only a few external components to be operable when connected to the controller 1104. A simple application using a single power source requires six wires: two wires are used for power and four wires 1240 are used for SPI interface 1234 with controller 1104. A seventh connection may be added to send an interrupt to the controller 1104 to inform that a new valid angle can be read. At power up, the AS5055 position sensor 1200 performs a full power up sequence, including an angle measurement. The completion of this cycle is represented as the INT output 1242 and the angle value is stored in an internal register. Once this output is set, the AS5055 position sensor 1200 pauses into the sleep mode. The controller 1104 can respond to an INT request at INT output 1242 by reading the angle value from AS5055 position sensor 1200 through SPI interface 1234. Once the controller 1104 reads the angle value, the INT output 1242 is cleared again. Sending a "read angle" command by controller 1104 to position sensor 1200 through SPI interface 1234 also automatically powers up the chip and initiates another angle measurement. As soon as the controller 1104 completes reading the angle value, the INT output 1242 is cleared and the new result is stored in the angle register. Completion of the angle measurement is again indicated by setting the INT output 1242 and the corresponding flag in the status register.

Due to the measurement principle of the AS5055 position sensor 1200, only a single angular measurement is performed in a very short time (600 μ s) after each power-up sequence. AS soon AS the measurement of an angle is completed, the AS5055 position sensor 1200 is suspended to a power-down state. On-chip filtering of angle values according to digital averaging is not performed, as this would require more than one angle measurement and thus longer power-up time, which is undesirable in low power applications. Angular jitter may be reduced by averaging the number of angular samples in the controller 1104. For example, averaging four samples may reduce jitter by 6dB (50%).

Fig. 13 is a cross-sectional view of the end effector 2502 of the surgical instrument 10 (fig. 1-4) illustrating the firing stroke of the I-beam 2514 relative to tissue 2526 grasped within the end effector 2502 according to one aspect of the present disclosure. The end effector 2502 is configured to operate with the surgical instrument 10 illustrated in fig. 1-4. The end effector 2502 includes an anvil 2516 and an elongate channel 2503, with a staple cartridge 2518 positioned in the elongate channel 2503. The firing rod 2520 can be translated distally and proximally along the longitudinal axis 2515 of the end effector 2502. When the end effector 2502 is not articulated, the end effector 2502 is in-line with the axis of the instrument. An I-beam 2514 including a cutting edge 2509 is illustrated at a distal portion of the firing bar 2520. A wedge sled 2513 is positioned in the staple cartridge 2518. As the I-beam 2514 translates distally, the cutting edge 2509 contacts and can cut tissue 2526 located between the anvil 2516 and the staple cartridge 2518. Also, the I-beam 2514 contacts the wedge sled 2513 and pushes it distally, causing the wedge sled 2513 to contact the staple driver 2511. The staple drivers 2511 can be driven upwardly into the staples 2505 such that the staples 2505 are advanced through the tissue and into pockets 2507 defined in the anvil 2516, the pockets 2507 forming the staples 2505.

An example I-beam 2514 firing member stroke is shown by a chart 2529 aligned with the end effector 2502. Alignment of exemplary tissue 2526 with the end effector 2502 is also shown. The firing member stroke may include a stroke start position 2527 and a stroke end position 2528. During the I-beam 2514 firing member stroke, the I-beam 2514 may be advanced distally from a start of stroke position 2527 to an end of stroke position 2528. The I-beam 2514 is illustrated at one example position of a stroke start position 2527. The I-beam 2514 firing member stroke chart 2529 illustrates five firing member stroke zones 2517, 2519, 2521, 2523, 2525. In the first firing stroke zone 2517, the I-beam 2514 may begin to advance distally. In the first firing stroke zone 2517, the I-beam 2514 may contact the wedge sled 2513 and begin moving it distally. However, in the first region, the cutting edge 2509 may not contact the tissue and the wedge sled 2513 may not contact the staple drivers 2511. After the static friction force is overcome, the force driving the I-beam 2514 in the first region 2517 may be substantially constant.

In the second firing member stroke zone 2519, the cutting edge 2509 can begin to contact and cut tissue 2526. Also, the wedge sled 2513 can begin to contact the staple drivers 2511 to drive the staples 2505. The force driving the I-beam 2514 may begin to rise. As shown, due to the manner in which the anvil 2516 pivots relative to the staple cartridge 2518, tissue initially encountered may be compressed and/or thinned. In the third firing member stroke zone 2521, the cutting edge 2509 can continuously contact and cut tissue 2526, and the wedge sled 2513 can repeatedly contact the staple drivers 2511. The force driving the I-beam 2514 may be smoothed in the third region 2521. Through the fourth firing stroke region 2523, the force driving the I-beam 2514 may begin to fall. For example, tissue in the portion of the end effector 2502 corresponding to the fourth firing region 2523 may be compressed less than tissue proximate to the pivot point of the anvil 2516, requiring less cutting force. Also, the cutting edge 2509 and wedge slide 2513 can reach the end of tissue 2526 while in the fourth region 2523. When the I-beam 2514 reaches the fifth region 2525, the tissue 2526 may be severed completely. The wedge sled 2513 can contact one or more staple drivers 2511 at or near the end of the tissue. The force urging the I-beam 2514 through the fifth region 2525 may be reduced, and in some examples, may be similar to the force driving the I-beam 2514 in the first region 2517. At the end of the firing member stroke, the I-beam 2514 can reach an end-of-stroke position 2528. The positioning of the firing member stroke regions 2517, 2519, 2521, 2523, 2525 in FIG. 18 is but one example. In some examples, the different regions may begin at different locations along the end effector longitudinal axis 2515, e.g., based on the positioning of tissue between the anvil 2516 and the staple cartridge 2518.

As described above, referring now to fig. 10-13, the electric motor 1122 positioned within the handle assembly of the surgical instrument 10 (fig. 1-4) can be utilized to advance and/or retract the firing system of the shaft assembly (including the I-beam 2514) relative to the end effector 2502 of the shaft assembly in order to staple and/or incise tissue captured within the end effector 2502. The I-beam 2514 can be advanced or retracted at a desired speed or within a desired speed range. The controller 1104 may be configured to control the speed of the I-beam 2514. The controller 1104 may be configured to be able to predict the speed of the I-beam 2514 based on, for example, various parameters of the power supplied to the electric motor 1122 (such as voltage and/or current) and/or other operating parameters or external influences of the electric motor 1122. The controller 1104 may be configured to predict a current speed of the I-beam 2514 based on previous values of current and/or voltage supplied to the electric motor 1122 and/or previous states of the system (e.g., speed, acceleration, and/or position). The controller 1104 may be configured to sense the velocity of the I-beam 2514 using an absolute positioning sensor system as described herein. The controller may be configured to be able to compare the predicted speed of the I-beam 2514 to the sensed speed of the I-beam 2514 to determine whether the power of the electric motor 1122 should be increased in order to increase the speed of the I-beam 2514 and/or decreased in order to decrease the speed of the I-beam 2514. U.S. patent No. 8,210,411 entitled "MOTOR-driving MOTOR braking actuation," which is incorporated herein by reference in its entirety. U.S. patent No. 7,845,537 entitled "SURGICAL INSTRUMENT HAVINGREGECORDING CAPABILITIES," which is incorporated herein by reference in its entirety.

Various techniques may be used to determine the force acting on the I-beam 2514. The force of the I-beam 2514 may be determined by measuring the current of the motor 2504, wherein the current of the motor 2504 is based on the load experienced by the I-beam 2514 as it advances distally. The force of the I-beam 2514 can be determined by positioning strain gauges on the drive member 120 (fig. 2), the firing member 220 (fig. 2), the I-beam 2514 (I-beam 178, fig. 20), the firing bar 172 (fig. 2), and/or on the proximal end of the cutting edge 2509. The force of the I-beam 2514 may be determined by: monitoring the I-beam 1 for a predetermined elapsed time period T ₁Followed by an actual position moved at a desired speed based on the current set speed of motor 2504, and based on motor 2504 over time period T ₁The current set-speed at the end compares the actual position of the I-beam 2514 with respect to the expected position of the I-beam 2514. Thus, if the actual position of the I-beam 2514 is less than the expected position of the I-beam 2514, the force on the I-beam 2514 is greater than the nominal force. Conversely, if the actual position of the I-beam 2514 is greater than the expected position of the I-beam 2514, the force on the I-beam 2514 is less than the nominal force. The difference between the actual position and the expected position of the I-beam 2514 is proportional to the force on the I-beam 2514 from the nominal force. Such techniques are described in attorney docket number END8195USNP, which is incorporated by reference herein in its entirety.

Fig. 14 illustrates a block diagram of a surgical instrument 2500 programmed to control distal translation of a displacement member according to one aspect of the present disclosure. In one aspect, the surgical instrument 2500 is programmed to control distal translation of a displacement member 1111, such as an I-beam 2514. The surgical instrument 2500 includes an end effector 2502, which end effector 2502 can include an anvil 2516, an I-beam 2514 (including a sharp cutting edge 2509), and a removable staple cartridge 2518. The end effector 2502, anvil 2516, I-beam 2514, and staple cartridge 2518 may be configured as described herein, for example, with reference to fig. 1-13.

The position, movement, displacement, and/or translation of the linear displacement member 1111 (e.g., the I-beam 2514) may be measured by the absolute positioning system 1100, the sensor arrangement 1102, and the position sensor 1200, as shown in fig. 10-12, and represented in fig. 14 as the position sensor 2534. Since the I-beam 2514 is coupled to the longitudinally movable drive member 120, the position of the I-beam 2514 can be determined by measuring the position of the longitudinally movable drive member 120 using the position sensor 2534. Thus, in the following description, the position, displacement, and/or translation of the I-beam 2514 may be achieved by the position sensor 2534 as described herein. The control circuit 2510 (such as the control circuit 700 depicted in fig. 5A and 5B) may be programmed to control translation of a displacement member 1111 (such as the I-beam 2514), as described in connection with fig. 10-12. In some examples, the control circuitry 2510 can include one or more microcontrollers, microprocessors, or other suitable processors for executing instructions that cause the one or more processors to control the displacement member (e.g., the I-beam 2514) in the manner described. In one aspect, the timer/counter circuit 2531 provides an output signal, such as an elapsed time or a digital count, to the control circuit 2510 to correlate the position of the I-beam 2514 as determined by the position sensor 2534 with the output of the timer/counter circuit 2531, such that the control circuit 2510 can determine the position of the I-beam 2514 relative to a starting position at a particular time (t). The timer/counter circuit 2531 may be configured to be able to measure elapsed time, count external events, or time external events.

The control circuit 2510 can generate a motor set point signal 2522. The motor set point signal 2522 may be provided to the motor controller 2508. The motor controller 2508 can include one or more circuits configured to provide motor drive signals 2524 to the motor 2504 to drive the motor 2504, as described herein. In some examples, motor 2504 may be a brushed DC electric motor, such as motor 82, motor 714, motor 1120 shown in fig. 1, 5B, 10. For example, the speed of motor 2504 may be proportional to the voltage of motor drive signal 2524. In some examples, the motor 2504 can be a brushless Direct Current (DC) electric motor, and the motor drive signals 2524 can include Pulse Width Modulated (PWM) signals provided to one or more stator windings of the motor 2504. Also, in some examples, the motor controller 2508 may be omitted, and the control circuit 2510 may generate the motor drive signal 2524 directly.

Motor 2504 may receive power from energy source 2512. The energy source 2512 may be or include a battery, a super capacitor, or any other suitable energy source 2512. The motor 2504 may be mechanically coupled to the I-beam 2514 via a transmission 2506. The transmission 2506 may include one or more gears or other linkage components to couple the motor 2504 to the I-beam 2514. The position sensor 2534 may sense the position of the I-beam 2514. The position sensor 2534 may be or include any type of sensor capable of generating position data indicative of the position of the I-beam 2514. In some examples, the position sensor 2534 can comprise an encoder configured to provide a series of pulses to the control circuit 2510 as the I-beam 2514 translates distally and proximally. The control circuit 2510 may track pulses to determine the position of the I-beam 2514. Other suitable position sensors may be used, including, for example, proximity sensors. Other types of position sensors may provide other signals indicative of the movement of the I-beam 2514. Also, in some examples, position sensor 2534 may be omitted. In the case where the motor 2504 is a stepper motor, the control circuit 2510 can track the position of the I-beam 2514 by aggregating the number and direction of steps that the motor 2504 has been commanded to perform. The position sensor 2534 can be located in the end effector 2502 or at any other portion of the instrument.

The control circuitry 2510 can communicate with one or more sensors 2538. The sensors 2538 can be positioned on the end effector 2502 and adapted to operate with the surgical instrument 2500 to measure various derivative parameters, such as gap distance versus time, tissue compression versus time, and anvil strain versus time. The sensors 2538 can include, for example, magnetic sensors, magnetic field sensors, strain gauges, pressure sensors, force sensors, inductive sensors (such as eddy current sensors), resistive sensors, capacitive sensors, optical sensors, and/or any other suitable sensors for measuring one or more parameters of the end effector 2502. The sensor 2538 may include one or more sensors.

The one or more sensors 2538 can comprise a strain gauge, such as a micro-strain gauge, configured to measure a magnitude of strain in the anvil 2516 during a clamped condition. The strain gauge provides an electrical signal whose magnitude varies with the magnitude of the strain. The sensor 2538 can comprise a pressure sensor configured to detect pressure generated by the presence of compressed tissue between the anvil 2516 and the staple cartridge 2518. The sensor 2538 can be configured to detect the impedance of a section of tissue located between the anvil 2516 and the staple cartridge 2518, which is indicative of the thickness and/or degree of filling of the tissue located therebetween.

The sensor 2538 can be configured to measure the force exerted by the closure drive system 30 on the anvil 2516. For example, one or more sensors 2538 can be positioned at the point of interaction between the closure tube 260 (FIG. 3) and the anvil 2516 to detect the closing force applied to the anvil 2516 by the closure tube 260. The force exerted on the anvil 2516 may be indicative of tissue compression experienced by a section of tissue trapped between the anvil 2516 and the staple cartridge 2518. One or more sensors 2538 can be positioned at various interaction points along the closure drive system 30 (FIG. 2) to detect the closure force applied to the anvil 2516 by the closure drive system 30. One or more sensors 2538 may be sampled in real time by the processor during the gripping operation, as described in fig. 5A-5B. The control circuit 2510 receives real time sample measurements to provide and analyze time based information and evaluates the closing force applied to the anvil 2516 in real time.

A current sensor 2536 may be used to measure the current drawn by the motor 2504. The force required to advance the I-beam 2514 may correspond to, for example, the current drawn by the motor 2504. The force is converted to a digital signal and provided to the control circuit 2510.

Using the physical characteristics of the instrument disclosed herein in connection with fig. 1-14, and with reference to fig. 14, the control circuit 2510 can be configured to be able to simulate the response of the actual system of the instrument in the software of the controller. The displacement member may be actuated to move the I-beam 2514 in the end effector 2502 at or near a target speed. The surgical instrument 2500 may include a feedback controller, which may be one of any feedback controller including, but not limited to, for example, a PID, status feedback, LQR, and/or adaptive controller. Surgical instrument 2500 may include a power source to, for example, convert signals from a feedback controller into physical inputs such as a housing voltage, a Pulse Width Modulated (PWM) voltage, a frequency modulated voltage, a current, a torque, and/or a force.

The actual drive system of the surgical instrument 2500 is configured to drive the displacement member, cutting member, or I-beam 2514 through a brushed DC motor having a gearbox and mechanical link to an articulation and/or knife system. Another example is an electric motor 2504 that operates a displacement member and articulation driver, e.g., an interchangeable shaft assembly. External influences are unmeasured, unpredictable effects of things such as tissue, surrounding body and friction on the physical system. Such external influences may be referred to as drag forces acting against the electric motor 2504. External influences such as drag forces may cause the operation of the physical system to deviate from the desired operation of the physical system.

Before explaining aspects of the surgical instrument 2500 in detail, it should be noted that the example aspects are not limited in their application or use to the details of construction and arrangement of parts illustrated in the accompanying drawings and description. The illustrative aspects may be implemented alone, in combination with other aspects, variations and modifications, and may be practiced or carried out in various ways. Furthermore, unless otherwise indicated, the terms and expressions employed herein have been chosen for the purpose of describing the illustrative aspects for the convenience of the reader and are not for the purpose of limiting the invention. Moreover, it should be understood that expressions of one or more of the aspects, and/or examples described below may be combined with any one or more of the expressions of the other aspects, and/or examples described below.

Various example aspects relate to a surgical instrument 2500 that includes an end effector 2502 with a motorized surgical stapling and severing implementation. For example, the motor 2504 can drive the displacement member distally and proximally along the longitudinal axis of the end effector 2502. The end effector 2502 can comprise a pivotable anvil 2516, and when deployed for use, the staple cartridge 2518 is positioned opposite the anvil 2516. The clinician may grasp tissue between the anvil 2516 and the staple cartridge 2518 as described herein. When the instrument 2500 is ready to be used, the clinician may provide a firing signal, such as by depressing a trigger of the instrument 2500. In response to the firing signal, the motor 2504 can drive the displacement member distally along the longitudinal axis of the end effector 2502 from a proximal stroke start position to an end of stroke position distal to the stroke start position. As the displacement member is translated distally, the I-beam 2514 with the cutting element positioned at the distal end can cut tissue between the staple cartridge 2518 and the anvil 2516.

In various examples, the surgical instrument 2500 can include a control circuit 2510, which control circuit 2510 is programmed to control distal translation of a displacement member (such as an I-beam 2514) based on one or more tissue conditions. The control circuit 2510 can be programmed to sense a tissue condition, such as thickness, directly or indirectly, as described herein. The control circuit 2510 can be programmed to select a firing control program based on tissue conditions. The firing control routine may describe distal movement of the displacement member. Different firing control programs may be selected to better address different tissue conditions. For example, when thicker tissue is present, the control circuit 2510 can be programmed to translate the displacement member at a lower speed and/or at a lower power. When thinner tissue is present, the control circuit 2510 can be programmed to translate the displacement member at a higher speed and/or at a higher power.

In some examples, the control circuit 2510 can operate the motor 2504 in an open-loop configuration for the first open-loop portion of the stroke of the displacement member initially. Based on the response of the instrument 2500 during the open loop portion of the stroke, the control circuit 2510 can select a firing control program. The response of the instrument may include the translation distance of the displacement member during the open loop portion, the time elapsed during the open loop portion, the energy provided to motor 2504 during the open loop portion, the sum of the pulse widths of the motor drive signals, and the like. After the open loop portion, the control circuit 2510 can implement the selected firing control program for the second portion of the displacement member stroke. For example, during the closed-loop portion of the stroke, the control circuit 2510 can modulate the motor 2504 based on translation data that describes the position of the displacement member in a closed-loop manner to translate the displacement member at a constant speed.

Fig. 15 shows a graph 2580 plotting two example displacement member strokes performed in accordance with an aspect of the present disclosure. Fig. 2580 includes two axes. Horizontal axis 2584 indicates elapsed time. The vertical axis 2582 indicates the position of the I-beam 2514 between the start of stroke position 2586 and the end of stroke position 2588. On the horizontal axis 2584, the control circuit 2510 may receive a firing signal and begin at t ₀An initial motor setting is provided. The open loop portion of the stroke of the displacement member being available at t ₀And t ₁An initial period of time elapsed in between.

A first example 2592 illustrates the response of the surgical instrument 2500 when thick tissue is positioned between the anvil 2516 and the staple cartridge 2518. During the open-loop part of the displacement member stroke, e.g. at t ₀And t ₁During an initial period in between, the I-beam 2514 may traverse from a stroke start position 2586 to a position 2594. The control circuit 2510 can determine that the position 2594 corresponds to a firing control routine that advances the I-beam 2514 at a selected constant velocity (Vslow), defined by t ₁Slope indications of the following example 2592 (e.g., in a closed loop portion). The control circuit 2510 can drive the I-beam 2514 to a speed Vslow to maintain Vslow by monitoring the position of the I-beam 2514 and modulating the motor setpoint 2522 and/or motor drive signal 2524. A second example 2590 illustrates the response of the surgical instrument 2500 when thin tissue is positioned between the anvil 2516 and the staple cartridge 2518.

At t ₀And t ₁During an initial period (e.g., an open loop period) in between, the I-beam 2514 may traverse from a stroke start position 2586 to a position 2596. The control circuitry may determine that position 2596 corresponds to a firing control program that advances the displacement member at a selected constant speed (Vfast). Because the tissue in example 2590 is thinner than the tissue in example 2592, it may provide less resistance to movement of the I-beam 2514. As a result, the I-beam 2514 may traverse a larger portion of the stroke during the initial period of time. Additionally, in some examples, thinner tissue (e.g., initiallyA greater portion of the displacement member stroke traversed during the time period) may correspond to a higher displacement member velocity after the initial time period.

Fig. 16-21 illustrate the end effector 2300 of the surgical instrument 2010, showing how the end effector 2300 may be articulated about an articulation joint 2270 relative to the elongate shaft assembly 2200, according to one aspect of the present disclosure. FIG. 16 is a partial perspective view of a portion of the end effector 2300 showing the elongate shaft assembly 2200 in an unarticulated orientation with portions thereof omitted for clarity. FIG. 17 is a perspective view of the end effector 2300 of FIG. 16, showing the elongate shaft assembly 2200 in an unarticulated orientation. FIG. 18 is an exploded assembly perspective view of the end effector 2300 of FIG. 16, showing an elongate shaft assembly 2200. FIG. 19 is a top view of the end effector 2300 of FIG. 16, showing the elongate shaft assembly 2200 in an unarticulated orientation. FIG. 20 is a top view of the end effector 2300 of FIG. 16, showing the elongate shaft assembly 2200 in a first articulation orientation. FIG. 21 is a top view of the end effector 2300 of FIG. 16, showing the elongate shaft assembly 2200 in a second articulation orientation.

Referring now to fig. 16-21, the end effector 2300 is adapted to cut and staple tissue and includes a first jaw in the form of an elongate channel 2302 configured to operably support a surgical staple cartridge 2304 therein. The end effector 2300 also includes a second jaw in the form of an anvil 2310 that is supported on the elongate channel 2302 for movement relative thereto. The elongate shaft assembly 2200 includes an articulation system 2800 that employs an articulation lock 2810. The articulation lock 2810 can be configured and operated to selectively lock the surgical end effector 2300 in various articulation positions. Such an arrangement enables the surgical end effector 2300 to rotate or articulate relative to the shaft closure sleeve 260 when the articulation lock 2810 is in its unlocked state. With particular reference to fig. 18, the elongate shaft assembly 2200 includes a spine 210, the spine 210 being configured to (1) slidably support a firing member 220 therein, and (2) slidably support a closure sleeve 260 (fig. 16) extending around the spine 210. The shaft closure sleeve 260 is attached to an end effector closure sleeve 272, which end effector closure sleeve 272 is pivotably attached to the closure sleeve 260 by a double pivot closure sleeve assembly 271.

The spine 210 also slidably supports a proximal articulation driver 230. The proximal articulation driver 230 has a distal end 231, the distal end 231 configured to operably engage an articulation lock 2810. The articulation lock 2810 also includes a shaft frame 2812 that attaches to the spine 210 in the various ways disclosed herein. The shaft frame 2812 is configured to movably support the proximal portion 2821 of the distal articulation driver 2820 therein. The distal articulation driver 2820 is movably supported within the elongate shaft assembly 2200 for selective longitudinal travel in the distal direction DD and the proximal direction PD along an articulation actuation axis AAA that is laterally offset from and parallel to the shaft axis SA-SA in response to articulation control motions applied thereto.

In fig. 17 and 18, the shaft frame 2812 includes a distal end portion 2814 having a pivot pin 2818 formed thereon. The pivot pin 2818 is adapted to be pivotally received within a pivot hole 2397 formed in a pivot base portion 2395 of the end effector mounting assembly 2390. The end effector mounting assembly 2390 is attached to the proximal end 2303 of the elongate channel 2302 by a spring pin 2393 or equivalent. The pivot pin 2818 defines an articulation axis B-B that is transverse to the shaft axis SA-SA to facilitate pivotal travel (i.e., articulation) of the end effector 2300 about the articulation axis B-B relative to the shaft frame 2812.

As shown in fig. 18, a link pin 2825 is formed on the distal end 2823 of the distal articulation link 2820 and is configured to be received within the aperture 2904 in the proximal end 2902 of the cross link 2900. The cross-link 2900 extends transversely across the shaft axis SA-SA and includes a distal end portion 2906. A distal link aperture 2908 is disposed through the distal end portion 2906 of the cross-link 2900 and is configured to pivotably receive a base pin 2398 therein that extends from the bottom of a pivot base portion 2395 of an end effector mounting assembly 2390. The base pin 2395 defines a link axis LA that is parallel to the articulation axis B-B. Fig. 17 and 20 illustrate the surgical end effector 2300 in an unarticulated position. The end effector axis EA defined by the elongate channel 2302 is aligned with the shaft axis SA-SA. The term "aligned with …" may mean "coaxially aligned with" or parallel to the shaft axis SA-SA. Movement of the distal articulation driver 2820 in the proximal direction PD will cause the cross-link 2900 to pull the surgical end effector 2300 in a counterclockwise CCW direction about the articulation axis B-B, as shown in fig. 19. Movement of the distal articulation driver 2820 in the distal direction DD will cause the cross-link 2900 to move the surgical end effector 2300 in a counterclockwise CCW direction about the articulation axis B-B, as shown in fig. 21. As shown in fig. 21, cross-link 2900 has a curved shape that allows cross-link 2900 to bend about articulation pin 2818 as surgical end effector 2300 is articulated in that direction. The articulation angle 2700 between the end effector axis EA and the shaft axis SA-SA is about sixty-five degrees (65 °) when the surgical end effector 2300 is in the fully articulated position on either side of the shaft axis SA-SA. Thus, the range of articulation on either of the shaft axes is one degree (1 °) to sixty-five degrees (65 °).

Fig. 19 illustrates the articulation joint 2270 in an upright position, i.e., at a zero angle θ with respect to the longitudinal direction depicted as the shaft axis SA, according to an aspect ₀. FIG. 20 illustrates the articulation joint 2270 of FIG. 19 at a first angle θ defined between the shaft axis SA and the end effector axis EA, according to one aspect ₁Articulation is performed in one direction. FIG. 21 illustrates the articulation joint 2270 of FIG. 19 at a second angle θ defined between the shaft axis SA and the end effector axis EA ₂Articulation is performed in the other direction.

The surgical end effector 2300 of fig. 16-21 includes a surgical cutting and stapling device that employs a firing member 220 of the various types and configurations described herein. However, the surgical end effector 2300 may comprise other forms of surgical end effectors that do not cut and/or staple tissue. The intermediate support member 2950 is pivotally and slidably supported relative to the spine 210. In FIG. 18, the intermediate support member 2950 includes a slot 2952, the slot 2952 being adapted to receive a pin 2954 therein, the pin 2954 protruding from the spine 210. This enables the intermediate support member 2950 to pivot and translate relative to the pin 2954 as the surgical end effector 2300 is articulated. A pivot pin 2958 protrudes from the underside of the intermediate support member 2950 to be pivotally received within a corresponding pivot hole 2399 provided in a base portion 2395 of the end effector mounting assembly 2390. The intermediate support member 2950 also includes a slot 2960 for receiving the firing member 220 therethrough. The intermediate support member 2950 serves to provide lateral support to the firing member 220 as the firing member 220 flexes to accommodate articulation of the surgical end effector 2300.

The surgical instrument can also be configured to determine the angle of orientation of the end effector 2300. In various aspects, the position sensor 1112 of the sensor arrangement 1102 can include, for example, one or more magnetic sensors, analog rotation sensors (such as potentiometers), analog hall effect sensor arrays that output a unique combination of position signals or values. In one aspect, the articulation joint 2270 of the aspect illustrated in fig. 16-21 can further include an articulation sensor arrangement configured to determine an angular position (i.e., an articulation angle) of the end effector 2300 and provide a unique position signal corresponding thereto.

The articulation sensor arrangement may be similar to the sensor arrangement 1102 described above and shown in fig. 10-12. In this regard, the articulation sensor arrangement may include a position sensor and a magnet that is operably coupled to the articulation joint 2270 such that it rotates in unison with the rotation of the articulation joint 2270. The magnet may be coupled to the pivot pin 2818, for example. The position sensor includes one or more magnetic sensing elements, such as hall effect sensors, and is positioned near the magnet, within or adjacent to the articulation joint 2270. Thus, as the magnet rotates, the magnetic sensing element of the position sensor determines the absolute angular position of the magnet. When the magnet is coupled to the articulation joint 2270, the angular position of the magnet relative to the position sensor corresponds to the angular position of the end effector 2300. Thus, the articulation sensor arrangement is capable of determining the angular position of the end effector as the end effector is articulated.

In another aspect, the surgical instrument is configured to be able to determine the angle at which the end effector 2300 is positioned in an indirect manner by monitoring the absolute position of the articulation driver 230 (fig. 3). When the position of the articulation driver 230 corresponds to the angle at which the end effector 2300 is oriented in a known manner, the absolute position of the articulation driver 230 can be tracked and then translated to the angular position of the end effector 2300. In this regard, the surgical instrument includes an articulation sensor arrangement configured to be capable of determining an absolute linear position of the articulation driver 230 and providing a unique position signal corresponding thereto. In some aspects, the articulation sensor arrangement or a controller operably coupled to the articulation sensor arrangement is additionally configured to translate or calculate the angular position of the end effector 2300 based on the unique position signals.

In this regard, the articulation sensor arrangement may likewise be similar to the sensor arrangement 1102 described above and shown in fig. 10-12. In one aspect similar to that shown in fig. 10 with respect to displacement member 1111, the articulation sensor arrangement includes a position sensor and a magnet that rotates once per full stroke of the longitudinally movable articulation driver 230. The position sensor includes one or more magnetic sensing elements (such as hall effect sensors) and is placed in proximity to the magnet. Thus, as the magnet rotates, the magnetic sensing element of the position sensor determines the absolute angular position of the magnet through one revolution.

In one aspect, a single rotation of the sensor element associated with the position sensor is equivalent to the longitudinal linear displacement d1 of the longitudinally movable articulation driver 230. In other words, d1 is the longitudinal linear distance that the longitudinal movable articulation driver 230 moves from point "a" to point "b" after a single rotation of the sensor element coupled to the longitudinal movable articulation driver 230. The articulation sensor arrangement may be connected via a gear reduction, which allows the position sensor to complete only one revolution for the full stroke of the longitudinally movable articulation driver 230. In other words, d1 may be equal to the full stroke of articulation driver 230. The position sensor is configured to be able to then transmit a unique position signal corresponding to the absolute position of the articulation driver 230 to the controller 1104, such as in those aspects depicted in fig. 10. Upon receiving the unique position signal, the controller 1104 is then configured to execute logic to determine the angular position of the end effector corresponding to the linear position of the articulation driver 230 by: for example, querying a lookup table that returns values for the pre-calculated angular position of the end effector 2300, calculating the angular position of the end effector 2300 via an algorithm using the linear position of the articulation drive 230 as an input, or performing any other such method known in the art.

In various aspects, any number of magnetic sensing elements may be employed on the articulation sensor arrangement, such as magnetic sensors that are categorized according to whether they measure the entire magnetic field or vector components of the magnetic field. The number of magnetic sensing elements utilized corresponds to the desired resolution sensed by the articulation sensor arrangement. In other words, the greater the number of magnetic sensing elements used, the finer the degree of articulation that can be sensed by the articulation sensor arrangement. The techniques for producing the two types of magnetic sensors described above encompass a number of aspects of physics and electronics. Technologies for magnetic field sensing include detection coils, flux gates, optical pumps, nuclear spins, superconducting quantum interferometers (SQUIDs), hall effects, anisotropic magnetoresistance, giant magnetoresistance, magnetic tunnel junctions, giant magnetoimpedances, magnetostrictive/piezoelectric composites, magnetodiodes, magnetotransistors, optical fibers, magneto-optical, and magnetic sensors based on micro-electromechanical systems, among others.

In one aspect, the position sensors of various aspects of the articulation sensor arrangement may be implemented in a manner similar to the positioning system shown in FIG. 12 for tracking the position of displacement member 1111. In one such aspect, the articulation sensor arrangement may be implemented AS an AS5055EQFT monolithic magnetic rotary position sensor, available from Austria Microsystems, AG. The position sensor interfaces with the controller to provide an absolute positioning system for directly or indirectly determining the absolute angular position of the end effector 2300. The position sensor is a low voltage and low power component and includes four hall effect elements 7128A, 7128B, 7128C, 7128D located in a region 1230 of the position sensor 1200 above the magnet 1202 (fig. 11). A high resolution ADC1232 and an intelligent power management controller 1238 are also provided on the chip. CORDIC processor 1236 (for Coordinate Rotation digital computer (CORDIC)), also known as the bitwise and Volder algorithms, is provided to perform simple and efficient algorithms to compute hyperbolic and trigonometric functions, requiring only addition, subtraction, bit shifting and table lookup operations. The angular position, alarm bits, and magnetic field information are transmitted to the controller 1104 over a standard serial communication interface, such as SPI interface 1234. The position sensor 1200 provides 12 or 14 bit resolution. The position sensor 1200 may be an AS5055 chip provided in a small QFN 16-pin 4 × 4 × 0.85mm package.

Referring to fig. 1-4 and 10-21, the absolute position feedback signal/value from absolute positioning system 1100 may be used to determine the position of articulation joint 2270 and the position of I-beam 178 (fig. 4). In one aspect, the articulation angle θ may be determined fairly accurately based on the drive member 120 of the surgical instrument 10. As described above, movement of the longitudinally movable drive member 120 (fig. 2) may be tracked by the absolute positioning system 1100, wherein the absolute positioning system 1100 may actually track movement of the articulation system by the drive member 120 when the articulation driver is operably coupled to the firing member 220 (fig. 3) by, for example, the clutch assembly 400 (fig. 3). As a result of tracking the movement of the articulation system, the controller of the surgical instrument may track the articulation angle θ of the end effector 2300 (e.g., the end effector 2300). In various circumstances, as a result, the articulation angle θ may be determined from the longitudinal displacement DL of the drive member 120. Since the longitudinal displacement DL of the drive member 120 can be accurately determined based on the absolute position signal/value provided by the absolute positioning system 1100, the articulation angle θ can be determined from the longitudinal displacement DL.

In another aspect, the articulation angle θ may be determined by positioning a sensor on the articulation joint 2270. The sensor may be configured to sense rotation of the articulation joint 2270 using an absolute positioning system 1100 adapted to measure absolute rotation of the articulation joint 2270. For example, the sensor arrangement 1102 includes a position sensor 1200, a magnet 1202, and a magnet holder 2270 adapted to sense rotation of the articulation joint 1204. The position sensor 1200 includes one or more magnetic sensing elements (such as hall elements) and is placed in proximity to the magnet 1202. The position sensor 1200 depicted in fig. 12 may be adapted to measure the angle of rotation of the articulation joint 2270. Thus, as the magnet 1202 rotates, the magnetic sensing element of the position sensor 1200 determines the absolute angular position of the magnet 1202 located on the articulation joint 2270. This information is provided to the microcontroller 1104 to calculate the articulation angle of the articulation joint 2270. Accordingly, the articulation angle of the end effector 2300 may be determined by an absolute positioning system 1100 adapted to measure the absolute rotation of the articulation joint 2270.

In one aspect, the firing rate or speed of the I-beam 178 may be varied depending on the articulation angle of the end effector 2300 to reduce the firing force on the firing drive system 80, and in particular, to reduce the firing force of the I-beam 80 among other components of the firing drive system 178 discussed herein. To accommodate the variable firing force of the I-beam 178 as a function of the articulation angle of the end effector 2300, a variable motor control voltage may be applied to the motor 82 to control the speed of the motor 82. The speed of the motor 82 may be controlled by comparing the firing force of the I-beam 178 to a different maximum threshold based on the articulation angle of the end effector 2300. The speed of the electric motor 82 may be varied by adjusting, for example, the voltage, current, Pulse Width Modulation (PWM), or duty cycle (0% to 100%) applied to the motor 82.

Having described techniques for measuring the articulation angle of the articulation joint 2270 and driving the longitudinally movable drive member 120, the firing member 220, the firing bar 172, or the I-beam 178 with the firing drive system 80 of the surgical instrument 10 (fig. 1-4), the present specification now turns to fig. 13, 14, and 22-27 for describing various techniques for controlling the firing rate or speed of the I-beam 2514 or the firing bar 2520 based on the articulation angle of the end effector 2502.

FIG. 22 is a graph 4500 of firing rate (speed) of an I-beam 2514 as a function of articulation angle of the end effector 2502 according to one or more aspects of the present disclosure. The horizontal axis 4502 represents the end effector 2502 articulation angle, which varies, for example, from-65 to +65 degrees, and the vertical axis 4504 represents the I-beam 2514 firing rate from 0mm/sec to 1.0Y mm/sec, where Y is a scaling factor. For example, when Y is 20, vertical axis 4504 scales from 0mm/sec to 20 mm/sec. The curve 4506 illustrates that the firing rate of the I-beam 2514 varies non-linearly and symmetrically about 0 ° as the articulation angle of the end effector 2502 changes from-65 ° to +65 °. A maximum I-beam 2514 firing rate of 1.0Y occurs at an end effector 2514 articulation angle of 0 °, in other words, when the end effector axis EA and the shaft axis SA are aligned. When the end effector 2502 is articulated from 0 ° to +65 ° or from either 0 ° to-65 °, the firing rate of the I-beam 2514 decreases non-linearly from 1.0Y to 0.5Y.

FIG. 23 is a graphical illustration 4510 of an I-beam 2514 firing force as a function of firing stroke displacement of the I-beam 2514 according to one or more aspects of the present disclosure. The horizontal axis 4512 represents the firing stroke displacement of the I-beam 2514 from 0mm (beginning of firing stroke) to 1.0Xmm (end of firing stroke), where X is a scaling factor associated with the nominal length of the staple cartridge. For example, the nominal length of the staple cartridge is in the range of 10mm to 60 mm. The vertical axis 4514 represents an I-beam 2514 firing force from 0N to 1.00Y N (newtons), where Y is the scaling factor. In one aspect, the force of firing member 2520 varies from 0N to 900N (0 lbf to 202.328 lbf). The graph 4510 shows three curves 4516, 4518, 4520. When the I-beam 2514 is advanced distally at a constant speed, the first curve 4516 represents the I-beam 2514 firing force according to the firing stroke displacement of the I-beam 2514 at an end effector 2502 articulation angle (end effector axis EA and shaft axis SA aligned) of 0 °. The second curve 4518 represents the I-beam 2514 firing force according to the firing stroke displacement of the I-beam 2514 at an end effector 2502 articulation angle of ± 65 ° as the I-beam 2514 advances distally at a constant speed. In other words, the speed of the motor 2504 is not changed according to the articulation angle of the end effector 2502. As shown in the second curve 4520 relative to the first curve 4516, the I-beam force as a function of the firing stroke displacement of the I-beam 2514 is greater as the I-beam 2514 is advanced distally at a constant speed at an articulation angle of the end effector 2502 of + -65 deg.. For example, as shown in FIG. 22, the third curve 4520 illustrates an overall lower I-beam 2514 firing force as a function of firing stroke displacement of the I-beam 2514, such as by varying the speed of the motor 2504 from + -65 deg. depending on the articulation angle of the end effector 2502.

Various techniques may be used to determine the force acting on firing member 2520. In one aspect, the firing member force can be determined by measuring the motor 2504 current, wherein the motor 2504 current is based on the load experienced by the firing member 2520 as it advances distally. In another aspect, the I-beam 2514 firing force can be determined by positioning a strain gauge on the drive member 120 (fig. 2), the firing member 220 (fig. 2), the firing member 2520, the firing bar 172 (fig. 2), and/or the I-beams 2514, 178 (fig. 4). In another aspect, the I-beam 2514 firing force may be determined by: monitoring the I-beam 2514 for a predetermined elapsed time period T ₁Followed by an actual position moved at a desired speed based on the current set speed of motor 2504, and based on motor 2504 over time period T ₁The current set-speed at the end compares the actual position of the I-beam 2514 with respect to the expected position of the I-beam 2514. Thus, if the actual position of the I-beam 2514 is less than the expected position of the I-beam 2514, the force on the I-beam 2514 is greater than the nominal force. Conversely, if the actual position of the I-beam 2514 is greater than the expected position of the I-beam 2514, the force on the I-beam 2514 is less than the nominal force. The difference between the actual position and the expected position of the I-beam 2514 is proportional to the force on the I-beam 2514 from the nominal force. The latter technique is described in detail in commonly owned attorney docket number END8195USNP filed on even date herewith, which is incorporated by reference in its entirety. As the firing force of the I-beam 2514 varies depending on the articulation angle of the end effector 2502,varying the control voltage applied to the motor 2504 can be employed to control the speed of the motor 2504 through different maximum current thresholds related to the articulation angle of the end effector 2502 to generally reduce the firing force on the I-beam 2514 and the force with which the I-beam 2514 is fired. This technique is described below in conjunction with fig. 23.

FIG. 24 is a graphical illustration 4530 of an I-beam 2514 firing force as a function of firing stroke displacement of the I-beam 2514 according to one or more aspects of the present disclosure. Horizontal axis 4532 represents a firing stroke displacement from 0mm to 1.0X mm, where X is a scaling factor associated with the nominal length of the staple cartridge. For example, the nominal length of the staple cartridge is in the range of 10mm to 60 mm. The vertical axis 4534 represents an I-beam 2514 firing force from 0N to 1.00Y N, where Y is the scaling factor. In one aspect, the I-beam 2514 firing force varies from 0N to 900N (0 lbf to 202.328 lbf). The graph 4530 illustrates three curves 4536, 4538, 4540 and two thresholds 4542, 4544 based on the articulation angle of the end effector 2502 to reduce the firing force and force fired on the I-beam 2514. A first curve 4536 represents the I-beam 2514 firing force displaced according to the firing stroke at an end effector 2502 articulation angle of 0 ° (end effector axis EA and shaft axis SA aligned) as the I-beam 2514 advances distally at a constant speed. The second curve 4538 represents the I-beam 2514 firing force displaced in accordance with the firing stroke of the I-beam 2514 at an end effector 2502 articulation angle of 65 ° as the firing member advances distally at a variable speed set by the articulation angle. The third curve 4540 represents the I-beam 2514 firing force at a firing stroke displacement of the I-beam 2514 according to an end effector 2502 articulation angle of 65 ° when the I-beam 2514 is advanced at a constant desired speed with a practical battery capacity (V-a) limit.

The graph 4530 also illustrates variable I-beam 2514 firing force trigger thresholds 4542, 4544 based on the articulation angle of the end effector 2502, which results in a variable I-beam 2514 firing rate throughout the I-beam 2514 firing stroke. The upper threshold 4542 is for an end effector 2502 articulation angle of 65 ° and the lower threshold 4544 is for an end effector 2502 articulation angle of 0 °. With the end effector 2502 articulation angle set to 65 °, the I-beam 2514 advances at a variable speed until the I-beam 2514 firing force crosses the upper threshold 4542, at which point an algorithm adjusts the speed of the motor 2504 to a desired speed until the firing force of the I-beam 2514 drops below the upper threshold 4542 of the firing force of the I-beam 2514 and then maintains the speed of the motor 2054 constant. The I-beam 2514 is then advanced distally at a constant desired speed. With the articulation angle of the end effector 2502 set to 0 °, the I-beam 2514 advances at a variable speed until the firing force of the I-beam 2514 crosses the lower threshold 4544 at which point an algorithm adjusts the speed of the motor 2504 to a constant desired speed. The I-beam 2514 is advanced distally at a constant desired speed. This operation is further described below in conjunction with fig. 24. The upper and lower threshold values 4542, 4544, as well as intervening threshold values therebetween that vary based on the articulation angle of the end effector 2502, are non-linear over the firing stroke displacement of the staple cartridge 2518. In other aspects, the thresholds 4542, 4544 may be straight line constants, or may be straight lines having a slope. Regardless of how the firing force of the I-beam 2514 is determined, the thresholds 4542, 4544 represent the firing force of the I-beam 2514.

As described above, the I-beam 2514 firing force may be determined by the motor 2504 current, a strain gauge, or by subjecting the I-beam 2514 to a predetermined time period t ₁Is expressed relative to an expected position of the I-beam 2514 advanced distally at a set motor 2514 speed. In the latter configuration, referring also to fig. 25, the surgical instrument further includes a timer/counter circuit 2531 coupled to the control circuit 2510, wherein the timer/counter circuit 2531 is configured to measure elapsed time. The control circuit 2510 is configured to set a speed of the motor 2504, receive an initial position of the I-beam 2514 from the position sensor 2534, receive a reference time t1 corresponding to the initial position of the I-beam 2514 from the timer/counter circuit 2531, and determine the I-beam 2514 at the time t based on the set speed of the motor 2504 ₂The expected location of the device. The control circuit 2510 is further configured to receive the I-beam 2514 from the position sensor 2534 at time t ₂At time t, the I-beam 2514 is brought into position ₂In factPosition and I-Beam 2514 at time t ₂Is compared and based on the I-beam 2514 at time t ₂With the I-beam 2514 at time t ₂The difference between the expected positions to determine the firing force on the I-beam 2514.

Fig. 25 is a graph 4550 of an I-beam 2514 firing rate as a function of firing stroke displacement of the I-beam 2514 according to one or more aspects of the present disclosure. The horizontal axis 4552 represents the firing stroke displacement of the I-beam 2514 from 0mm to 1.0X mm, where X is a scaling factor associated with the nominal length of the staple cartridge. For example, the nominal length of the staple cartridge is in the range of 10mm to 60 mm. The vertical axis 4554 represents an I-beam 2514 firing rate from 0N to 1.00Y N, where Y is the zoom factor. In one aspect, the force of the I-beam 2514 varies from 0mm/sec to 20 mm/sec. The graph 4550 shows three curves 4556, 4558, 4559. The first curve 4556 is the I-beam 2514 velocity set at an end effector articulation angle of 0 °. The firing rate of the I-beam 2514 increases over the initial displacement and remains constant throughout the remaining stroke with the motor 2504 set to a constant speed. A second curve 4558 is the firing rate of the I-beam 2514 at a 65 deg. end effector 2502 articulation angle setting. The firing rate of the I-beam 2514 increases over the initial displacement and remains constant throughout the remaining stroke, with the motor 2504 set to a variable speed based on the articulation angle of the end effector 2502. The third curve 4559 is the firing rate of the I-beam 2514 at a 65 ° end effector 2502 articulation angle setting. The I-beam 2514 increases in initial displacement and varies throughout the remaining stroke, and the motor 2504 is set to a constant desired speed with a practical battery capacity (V-a) limit.

Fig. 26 is a logic flow diagram depicting a process 4560 for a control program or logic configuration for controlling the velocity of a displacement member (such as an I-beam 2514) based on the articulation angle of the end effector 2502 in accordance with one or more aspects of the present disclosure. In the following description of process 4560 in fig. 26, reference should also be made to fig. 15 to 25. Accordingly, the control circuit 2510 determines 4562 the current articulation angle of the end effector 2502 based on the information received from the position sensor 2534. The control circuit 2510 sets 4564 the speed of the motor 2504 based on the articulation angle. The control circuit 2510 compares 4565 the current articulation angle with the previous articulation angle. If the articulation angle has not changed, the process 4560 continues along the "No" branch (N) and the control circuit 2510 determines 4562 the articulation angle while maintaining the speed of the motor 2504 constant. If the articulation angle of the end effector 2502 changes, the process 4560 continues along the "yes" branch (Y) and the control circuit 2501 adjusts the speed of the 4566 motor 2504 based on the new articulation angle. The control circuit 2510 compares 4567 the actual position of the I-beam 2514 with the end of the firing stroke position. If the I-beam 2514 is at the end of the firing stroke, the process 4560 continues along the YES branch (Y) and ends 4568. If the I-beam 2514 has not reached the end of the firing stroke, the process 4560 continues along the "No" branch (N) and the articulation angle is determined 4562. The process 4560 continues until the position of the I-beam 2514 reaches the end of the firing stroke of the 4569I-beam 2514.

Fig. 27 is a logic flow diagram depicting a process 4570 of a control program or logic configuration for controlling the velocity of a displacement member, such as an I-beam 2514, based on the articulation angle of the end effector 2502 in accordance with one or more aspects of the present disclosure. In the following description of process 4570 in fig. 27, reference should also be made to fig. 15 to 25. Accordingly, the control circuit 2510 determines 4572 the articulation angle of the end effector 2502 based on the information received from the position sensor 2534. In examples where the displacement member is an I-beam 2514, the control circuit 2510 selects 4574 a force threshold for the I-beam 2514 based on the articulation angle of the end effector 2502. The control circuit 2510 provides a motor set point signal 2522 to the motor controller 2508, which motor controller 2508 provides a motor drive signal 2524 to set 4576 the speed of the motor 2504 based on the angle of articulation of the end effector 2502. The control circuit 2510 determines 4578 the actual position of the I-beam 2514 and determines 4580 the firing force of the I-beam 2514 and compares 4582 the firing force of the I-beam 2514 to a threshold. If the firing force of the I-beam 2514 exceeds the threshold, the process continues along the YES (Y) branch and the speed of the motor 2504 is reduced 4584 until the firing force of the I-beam 2514 drops below the firing force threshold of the I-beam 2514. If the firing force of the I-beam 2514 is less than the threshold, the process continues along the NO branch and continues to determine 4578 the actual position of the I-beam 2514, determine 4580 the firing force of the I-beam 2514, and compare 4582 the firing force of the I-beam 2514 to the threshold until the firing force of the I-beam 2514 exceeds the threshold. The motor drive signal 2524 may be a varying voltage or current signal, a Pulse Width Modulation (PWM) signal, and/or a variable duty cycle signal. The control circuit 2510 compares the actual position of the I-beam 2514 to the end of the firing stroke position of the I-beam 2514. If the I-beam 2514 is at the end of the firing stroke, the process 4570 continues along the YES branch (Y) and ends 4588. If the I-beam 2514 has not reached the end of the firing stroke, the process 4570 continues along the NO branch (N) and the articulation angle of the end effector 2502 is determined 4572. The process 4570 continues until the I-beam 2514 reaches the end of the firing stroke.

The functions or processes 4560, 4570 described herein may be performed by any processing circuit described herein, such as the control circuit 700 described in connection with fig. 5-6, the circuits 800, 810, 820 described in fig. 7-9, the microcontroller 1104 described in connection with fig. 10 and 12, and/or the control circuit 2510 described in fig. 14.

Aspects of the motorized surgical instrument may be practiced without the specific details disclosed herein. Some aspects have been shown in block diagrams rather than in detail. Components of the present disclosure may be presented in terms of instructions to operate on data stored in a computer memory. An algorithm is a self-consistent sequence of steps leading to a desired result, where "step" refers to the manipulation of physical quantities which can take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. These signals may be referred to as bits, values, elements, symbols, characters, terms, numbers. These and similar terms may be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities.

In general, the aspects described herein, which may be implemented individually and/or collectively by a variety of hardware, software, firmware, or any combination thereof, may be viewed as being comprised of multiple types of "electronic circuitry". Thus, "electronic circuitry" includes electronic circuitry having at least one discrete circuit, electronic circuitry having at least one integrated circuit, electronic circuitry having at least one application specific integrated circuit, electronic circuitry forming a general purpose computing device configured by a computer program (e.g., a computer program that performs at least in part the processes described herein and/or a general purpose computer or processor configured by apparatus described herein), electronic circuitry forming memory means (e.g., forming random access memory), and/or electronic circuitry forming communication means (e.g., a modem, a communication switch, or an optoelectronic device). These aspects may be implemented in analog or digital form or a combination thereof.

The foregoing description has set forth aspects of the devices and/or processes using block diagrams, flowcharts, and/or examples that may include one or more functions and/or operations. Each function and/or operation within such block diagrams, flowcharts, or examples may be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or virtually any combination thereof. In one aspect, portions of the subject matter described herein may be implemented via Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), Digital Signal Processors (DSPs), Programmable Logic Devices (PLDs), circuits, registers, and/or software components (e.g., programs, subroutines, logic, and/or combinations of hardware and software components, logic gates, or other integrated formats). Aspects disclosed herein may be equivalently implemented in integrated circuits, in whole or in part, as one or more computer programs running on one or more computers (e.g., as one or more programs running on one or more computer systems), as one or more programs running on one or more processors (e.g., as one or more programs running on one or more microprocessors), as firmware, or as virtually any combination thereof, and designing the electronic circuits and/or writing the code for the software and/or hardware would be well within the skill of one of skill in the art in light of this disclosure.

The mechanisms of the subject matter disclosed herein are capable of being distributed as a program product in a variety of forms, and that an illustrative aspect of the subject matter described herein applies regardless of the particular type of signal bearing media used to actually carry out the distribution. Examples of signal bearing media include the following: recordable media such as floppy disks, hard disk drives, Compact Disks (CDs), Digital Video Disks (DVDs), digital tapes, computer memory, etc.; and a transmission-type medium such as a digital and/or analog communication medium (e.g., a fiber optic cable, a waveguide, a wired communications link, a wireless communication link (e.g., transmitter, receiver, transmission logic, reception logic), etc.).

The foregoing description of these aspects has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Modifications or variations are possible in light of the above teachings. The aspects were chosen and described in order to explain the principles and practical application, to thereby enable others skilled in the art to utilize the aspects and with various modifications as are suited to the particular use contemplated. The claims as filed herewith are intended to define the full scope.

Various aspects of the subject matter described herein are set forth in the following numbered examples: