Patent Publication Number: US-2022225986-A1

Title: Mechanisms for compensating for drivetrain failure in powered surgical instruments

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application claiming priority under 35 U.S.C. § 120 to U.S. patent application Ser. No. 16/567,469, titled MECHANISMS FOR COMPENSATING FOR DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, filed Sep. 11, 2019, now U.S. Patent Application Publication No. 2020/0000471, which is a divisional application claiming priority under 35 U.S.C. § 121 to U.S. patent application Ser. No. 15/043,259, titled MECHANISMS FOR COMPENSATING FOR DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, filed Feb. 12, 2016, which issued on Oct. 22, 2019 as U.S. Pat. No. 10,448,948, the entire disclosures of which are hereby incorporated by reference herein. 
     This application is related to commonly-owned U.S. patent application Ser. No. 15/043,254 and titled MECHANISMS FOR DETECTING DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,258,331, U.S. patent application Ser. No. 15/043,275 and titled MECHANISMS FOR DETECTING DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2017/0231627, U.S. patent application Ser. No. 15/043,289 and titled MECHANISMS FOR DETECTING DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2017/0231628, each of which is incorporated herein by reference in its entirety. 
     Commonly-owned U.S. patent application Ser. No. 14/984,488 and titled MECHANISMS FOR COMPENSATING FOR BATTERY PACK FAILURE IN POWERED SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,292,704, U.S. patent application Ser. No. 14/984,552 and titled SURGICAL INSTRUMENTS WITH SEPARABLE MOTORS AND MOTOR CONTROL CIRCUITS, now U.S. Pat. No. 10,265,068, and U.S. patent application Ser. No. 14/984,525 and titled MECHANISMS FOR COMPENSATING FOR DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,368,865, are also incorporated herein by reference in their entireties. 
    
    
     BACKGROUND 
     The present invention relates to surgical instruments and, in various arrangements, to surgical stapling and cutting instruments and staple cartridges for use therewith that are designed to staple and cut tissue. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The features of the various aspects are set forth with particularity in the appended claims. The various aspects, however, both as to organization and methods of operation, together with advantages thereof, may best be understood by reference to the following description, taken in conjunction with the accompanying drawings as follows: 
         FIG. 1  is a perspective, disassembled view of an electromechanical surgical system including a surgical instrument, an adapter, and an end effector, according to the present disclosure; 
         FIG. 2  is a perspective view of the surgical instrument of  FIG. 1 , according to at least one aspect of the present disclosure; 
         FIG. 3  is perspective, exploded view of the surgical instrument of  FIG. 1 , according to at least one aspect of the present disclosure; 
         FIG. 4  is a perspective view of a battery of the surgical instrument of  FIG. 1 , according to at least one aspect of the present disclosure; 
         FIG. 5  is a top, partially-disassembled view of the surgical instrument of  FIG. 1 , according to at least one aspect of the present disclosure; 
         FIG. 6  is a front, perspective view of the surgical instrument of  FIG. 1  with the adapter separated therefrom, according to at least one aspect of the present disclosure; 
         FIG. 7  is a side, cross-sectional view of the surgical instrument of  FIG. 1 , as taken through  7 - 7  of  FIG. 2 , according to at least one aspect of the present disclosure; 
         FIG. 8  is a top, cross-sectional view of the surgical instrument of  FIG. 1 , as taken through  8 - 8  of  FIG. 2 , according to at least one aspect of the present disclosure; 
         FIG. 9  is a perspective, exploded view of a end effector of  FIG. 1 , according to at least one aspect of the present disclosure; 
         FIG. 10A  is a top view of a locking member, according to at least one aspect of the present disclosure; 
         FIG. 10B  is a perspective view of the locking member of  FIG. 10A , according to at least one aspect of the present disclosure; 
         FIG. 11  is a schematic diagram of the surgical instrument of  FIG. 1 , according to at least one aspect of the present disclosure; 
         FIG. 12  is a perspective view, with parts separated, of an electromechanical surgical system, according to at least one aspect of the present disclosure; 
         FIG. 13  is a rear, perspective view of a shaft assembly and a powered surgical instrument, of the electromechanical surgical system of  FIG. 12 , illustrating a connection therebetween, according to at least aspect of the present disclosure; 
         FIG. 14  is a perspective view, with parts separated, of the shaft assembly of  FIG. 13 , according to at least aspect of the present disclosure; 
         FIG. 15  is a perspective view, with parts separated of a transmission housing of the shaft assembly of  FIG. 13 , according to at least aspect of the present disclosure; 
         FIG. 16  is a perspective view of a first gear train system that is supported in the transmission housing of  FIG. 15 , according to at least aspect of the present disclosure; 
         FIG. 17  is a perspective view of a second gear train system that is supported in the transmission housing of  FIG. 15 , according to at least aspect of the present disclosure; 
         FIG. 18  is a perspective view of a third drive shaft that is supported in the transmission housing of  FIG. 15 , according to at least aspect of the present disclosure; 
         FIG. 19  is a perspective view of a surgical instrument, according to at least one aspect of the present disclosure; 
         FIG. 20  is a circuit diagram of various components of the surgical instrument of  FIG. 19 , according to at least one aspect of the present disclosure; 
         FIG. 21  is a circuit diagram including a microphone in communication with a plurality of filters coupled to a plurality of logic gates in accordance with at least one aspect of the present disclosure; 
         FIG. 22  is a graph of a microphone&#39;s output in volts versus time in seconds, the graph representing is a vibratory response of a properly functioning surgical instrument of  FIG. 19  recorded by the microphone during operation of the surgical instrument in accordance with at least one aspect of the present disclosure; 
         FIG. 22A  is a filtered signal of the microphone output of  FIG. 22  in accordance with at least one aspect of the present disclosure; 
         FIG. 23  is a graph of a microphone&#39;s output in volts versus time in seconds, the graph representing is a vibratory response of a malfunctioning surgical instrument of  FIG. 19  recorded by the microphone during operation of the surgical instrument in accordance with at least one aspect of the present disclosure; 
         FIG. 23A  is a filtered signal of the microphone output of  FIG. 23  in accordance with at least one aspect of the present disclosure; 
         FIG. 24  is a circuit diagram including a sensor of the surgical instrument of  FIG. 19  coupled to a plurality of filters in communication with a microcontroller via a multiplexer and an analogue to digital converter in accordance with at least one aspect of the present disclosure; 
         FIG. 24A  is a circuit diagram including a sensor of the surgical instrument of  FIG. 19  coupled to a plurality of filters in communication with a microcontroller via a multiplexer and an analogue to digital converter in accordance with at least one aspect of the present disclosure; 
         FIGS. 24B-24D  illustrate structural and operational characteristics of a Band-pass filter of the surgical instrument of  FIG. 19  in accordance with at least one aspect of the present disclosure; 
         FIG. 25  is graph representing a filtered signal of a sensor output of the surgical instrument of  FIG. 19  in accordance with at least one aspect of the present disclosure; 
         FIG. 26  is a graph representing a processed signal of a sensor output of the surgical instrument of  FIG. 19  in accordance with at least one aspect of the present disclosure; 
         FIG. 27  is a graph representing the force needed to fire (FTF) the surgical instrument of  FIG. 19  in relation to a displacement position of a drive assembly of the surgical instrument from a starting position in accordance with at least one aspect of the present disclosure; 
         FIG. 28  is a graph representing the velocity of a drive assembly of the surgical instrument of  FIG. 19 , during a firing stroke, in relation to the displacement position of the drive assembly from a starting position in accordance with at least one aspect of the present disclosure; 
         FIG. 29  is a graph that represents acceptable limit modification based on zone of stroke location during a firing stroke of the surgical instrument of  FIG. 19  in accordance with at least one aspect of the present disclosure; 
         FIG. 30  is a graph that represents a processed signal of the output of a sensor of the surgical instrument of  FIG. 19  showing a shift in the frequency response of the processed signal due to load and velocity changes experienced by a drive assembly during a firing stroke in accordance with at least one aspect of the present disclosure; 
         FIG. 31  is a graph that represents a processed signal of vibrations captured by a sensor of the surgical instrument of  FIG. 19  during a zone of operation, the graph illustrating and acceptable limit, marginal limit, and critical limit for the zone of operation in accordance with at least one aspect of the present disclosure; 
         FIG. 32  is a logic diagram of the surgical instrument of  FIG. 19  in accordance with at least one aspect of the present disclosure; 
         FIG. 33  is a graph that represents a processed signal of vibrations captured by a sensor of the surgical instrument of  FIG. 19  in accordance with at least one aspect of the present disclosure; 
         FIG. 34  is a graph that represents a processed signal of vibrations captured by a sensor of the surgical instrument of  FIG. 19  in accordance with at least one aspect of the present disclosure; and 
         FIG. 35  is a graph that represents a processed signal of vibrations captured by a sensor of the surgical instrument of  FIG. 19  in accordance with at least one aspect of the present disclosure. 
     
    
    
     DESCRIPTION 
     Before explaining various forms of mechanisms for compensating for drivetrain failure in powered surgical instruments in detail, it should be noted that the illustrative forms are not limited in application or use to the details of construction and arrangement of parts illustrated in the accompanying drawings and description. The illustrative forms may be implemented or incorporated in other forms, variations and modifications, and may be practiced or carried out in various ways. Further, unless otherwise indicated, the terms and expressions employed herein have been chosen for the purpose of describing the illustrative forms for the convenience of the reader and are not for the purpose of limitation thereof. 
     Further, it is understood that any one or more of the following-described forms, expressions of forms, examples, can be combined with any one or more of the other following-described forms, expressions of forms, and examples. 
     Various forms are directed to mechanisms for compensating for drivetrain failure in powered surgical instruments. In one form, the mechanisms for compensating for drivetrain failure in powered surgical instruments may be configured for use in open surgical procedures, but has applications in other types of surgery, such as laparoscopic, endoscopic, and robotic-assisted procedures. 
       FIGS. 1-18  depict various aspects of a surgical system that is generally designated as  10 , and is in the form of a powered hand held electromechanical instrument configured for selective attachment thereto of a plurality of different end effectors that are each configured for actuation and manipulation by the powered hand held electromechanical surgical instrument. The aspects of  FIGS. 1-18  are disclosed in U.S. Patent Application Publication No. 2014/0110453, filed Oct. 23, 2012, and titled SURGICAL INSTRUMENT WITH RAPID POST EVENT DETECTION, now U.S. Pat. No. 9,265,585, U.S. Patent Application Publication No. 2013/0282052, filed Jun. 19, 2013, and titled APPARATUS FOR ENDOSCOPIC PROCEDURES, now U.S. Pat. No. 9,480,492, and U.S. Patent Application Publication No. 2013/0274722, filed May 10, 2013, and titled APPARATUS FOR ENDOSCOPIC PROCEDURES, now U.S. Pat. No. 9,492,146. 
     Referring to  FIGS. 1-3 , a surgical instrument  100  is configured for selective connection with an adapter  200 , and, in turn, adapter  200  is configured for selective connection with an end effector or single use loading unit or reload  300 . As illustrated in  FIGS. 1-3 , the surgical instrument  100  includes a handle housing  102  having a lower housing portion  104 , an intermediate housing portion  106  extending from and/or supported on lower housing portion  104 , and an upper housing portion  108  extending from and/or supported on intermediate housing portion  106 . Intermediate housing portion  106  and upper housing portion  108  are separated into a distal half-section  110   a  that is integrally formed with and extending from the lower portion  104 , and a proximal half-section  110   b  connectable to distal half-section  110   a  by a plurality of fasteners. When joined, distal and proximal half-sections  110   a,    110   b  define a handle housing  102  having a cavity  102   a  therein in which a circuit board  150  and a drive mechanism  160  is situated. 
     Distal and proximal half-sections  110   a,    110   b  are divided along a plane that traverses a longitudinal axis “X” of upper housing portion  108 , as seen in  FIGS. 2 and 3 . Handle housing  102  includes a gasket  112  extending completely around a rim of distal half-section and/or proximal half-section  110   a,    110   b  and being interposed between distal half-section  110   a  and proximal half-section  110   b.  Gasket  112  seals the perimeter of distal half-section  110   a  and proximal half-section  110   b.  Gasket  112  functions to establish an air-tight seal between distal half-section  110   a  and proximal half-section  110   b  such that circuit board  150  and drive mechanism  160  are protected from sterilization and/or cleaning procedures. 
     In this manner, the cavity  102   a  of handle housing  102  is sealed along the perimeter of distal half-section  110   a  and proximal half-section  110   b  yet is configured to enable easier, more efficient assembly of circuit board  150  and a drive mechanism  160  in handle housing  102 . 
     Intermediate housing portion  106  of handle housing  102  provides a housing in which circuit board  150  is situated. Circuit board  150  is configured to control the various operations of surgical instrument  100 . 
     Lower housing portion  104  of surgical instrument  100  defines an aperture (not shown) formed in an upper surface thereof and which is located beneath or within intermediate housing portion  106 . The aperture of lower housing portion  104  provides a passage through which wires  152  pass to electrically interconnect electrical components (a battery  156 , as illustrated in  FIG. 4 , a circuit board  154 , as illustrated in  FIG. 3 , etc.) situated in lower housing portion  104  with electrical components (circuit board  150 , drive mechanism  160 , etc.) situated in intermediate housing portion  106  and/or upper housing portion  108 . 
     Handle housing  102  includes a gasket  103  disposed within the aperture of lower housing portion  104  (not shown) thereby plugging or sealing the aperture of lower housing portion  104  while allowing wires  152  to pass therethrough. Gasket  103  functions to establish an air-tight seal between lower housing portion  106  and intermediate housing portion  108  such that circuit board  150  and drive mechanism  160  are protected from sterilization and/or cleaning procedures. 
     As shown, lower housing portion  104  of handle housing  102  provides a housing in which a rechargeable battery  156 , is removably situated. Battery  156  is configured to supply power to any of the electrical components of surgical instrument  100 . Lower housing portion  104  defines a cavity (not shown) into which battery  156  is inserted. Lower housing portion  104  includes a door  105  pivotally connected thereto for closing cavity of lower housing portion  104  and retaining battery  156  therein. 
     With reference to  FIGS. 3 and 5 , distal half-section  110   a  of upper housing portion  108  defines a nose or connecting portion  108   a.  A nose cone  114  is supported on nose portion  108   a  of upper housing portion  108 . Nose cone  114  is fabricated from a transparent material. A feedback indicator such as, for example, an illumination member  116  is disposed within nose cone  114  such that illumination member  116  is visible therethrough. Illumination member  116  is may be a light emitting diode printed circuit board (LED PCB). Illumination member  116  is configured to illuminate multiple colors with a specific color pattern being associated with a unique discrete event. 
     Upper housing portion  108  of handle housing  102  provides a housing in which drive mechanism  160  is situated. As illustrated in  FIG. 5 , drive mechanism  160  is configured to drive shafts and/or gear components in order to perform the various operations of surgical instrument  100 . In particular, drive mechanism  160  is configured to drive shafts and/or gear components in order to selectively move tool assembly  304  of end effector  300  (see  FIGS. 1 and 9 ) relative to proximal body portion  302  of end effector  300 , to rotate end effector  300  about a longitudinal axis “X” (see  FIG. 2 ) relative to handle housing  102 , to move anvil assembly  306  relative to cartridge assembly  308  of end effector  300 , and/or to fire a stapling and cutting cartridge within cartridge assembly  308  of end effector  300 . 
     The drive mechanism  160  includes a selector gearbox assembly  162  that is located immediately proximal relative to adapter  200 . Proximal to the selector gearbox assembly  162  is a function selection module  163  having a first motor  164  that functions to selectively move gear elements within the selector gearbox assembly  162  into engagement with an input drive component  165  having a second motor  166 . 
     As illustrated in  FIGS. 1-4 , and as mentioned above, distal half-section  110   a  of upper housing portion  108  defines a connecting portion  108   a  configured to accept a corresponding drive coupling assembly  210  of adapter  200 . 
     As illustrated in  FIGS. 6-8 , connecting portion  108   a  of surgical instrument  100  has a cylindrical recess  108   b  that receives a drive coupling assembly  210  of adapter  200  when adapter  200  is mated to surgical instrument  100 . Connecting portion  108   a  houses three rotatable drive connectors  118 ,  120 ,  122 . 
     When adapter  200  is mated to surgical instrument  100 , each of rotatable drive connectors  118 ,  120 ,  122  of surgical instrument  100  couples with a corresponding rotatable connector sleeve  218 ,  220 ,  222  of adapter  200  as shown in  FIG. 6 . In this regard, the interface between corresponding first drive connector  118  and first connector sleeve  218 , the interface between corresponding second drive connector  120  and second connector sleeve  220 , and the interface between corresponding third drive connector  122  and third connector sleeve  222  are keyed such that rotation of each of drive connectors  118 ,  120 ,  122  of surgical instrument  100  causes a corresponding rotation of the corresponding connector sleeve  218 ,  220 ,  222  of adapter  200 . 
     The mating of drive connectors  118 ,  120 ,  122  of surgical instrument  100  with connector sleeves  218 ,  220 ,  222  of adapter  200  allows rotational forces to be independently transmitted via each of the three respective connector interfaces. The drive connectors  118 ,  120 ,  122  of surgical instrument  100  are configured to be independently rotated by drive mechanism  160 . In this regard, the function selection module  163  of drive mechanism  160  selects which drive connector or connectors  118 ,  120 ,  122  of surgical instrument  100  is to be driven by the input drive component  165  of drive mechanism  160 . 
     Since each of drive connectors  118 ,  120 ,  122  of surgical instrument  100  has a keyed and/or substantially non-rotatable interface with respective connector sleeves  218 ,  220 ,  222  of adapter  200 , when adapter  200  is coupled to surgical instrument  100 , rotational force(s) are selectively transferred from drive mechanism  160  of surgical instrument  100  to adapter  200 . 
     The selective rotation of drive connector(s)  118 ,  120  and/or  122  of surgical instrument  100  allows surgical instrument  100  to selectively actuate different functions of end effector  300 . Selective and independent rotation of first drive connector  118  of surgical instrument  100  corresponds to the selective and independent opening and closing of tool assembly  304  of end effector  300 , and driving of a stapling/cutting component of tool assembly  304  of end effector  300 . Also, the selective and independent rotation of second drive connector  120  of surgical instrument  100  corresponds to the selective and independent articulation of tool assembly  304  of end effector  300  transverse to longitudinal axis “X” (see  FIG. 2 ). Additionally, the selective and independent rotation of third drive connector  122  of surgical instrument  100  corresponds to the selective and independent rotation of end effector  300  about longitudinal axis “X” (see  FIG. 2 ) relative to handle housing  102  of surgical instrument  100 . 
     As mentioned above and as illustrated in  FIGS. 5 and 8 , drive mechanism  160  includes a selector gearbox assembly  162 ; and a function selection module  163 , located proximal to the selector gearbox assembly  162 , that functions to selectively move gear elements within the selector gearbox assembly  162  into engagement with second motor  166 . Thus, drive mechanism  160  selectively drives one of drive connectors  118 ,  120 ,  122  of surgical instrument  100  at a given time. 
     As illustrated in  FIGS. 1-3 , handle housing  102  supports a control assembly  107  on a distal surface or side of intermediate housing portion  108 . The control assembly  107  is a fully-functional mechanical subassembly that can be assembled and tested separately from the rest of the instrument  100  prior to coupling thereto. 
     Control assembly  107 , in cooperation with intermediate housing portion  108 , supports a pair of finger-actuated control buttons  124 ,  126  and a pair rocker devices  128 ,  130  within a housing  107   a.  The control buttons  124 ,  126  are coupled to extension shafts  125 ,  127  respectively. In particular, control assembly  107  defines an upper aperture  124   a  for slidably receiving the extension shaft  125 , and a lower aperture  126   a  for slidably receiving the extension shaft  127 . 
     The control assembly  107  and its components (e.g., control buttons  124 ,  126  and rocker devices  128 ,  130 ) my be formed from low friction, self-lubricating, lubricious plastics or materials or coatings covering the moving components to reduce actuation forces, key component wear, elimination of galling, smooth consistent actuation, improved component and assembly reliability and reduced clearances for a tighter fit and feel consistency. This includes the use of plastic materials in the bushings, rocker journals, plunger bushings, spring pockets, retaining rings and slider components. Molding the components in plastic also provides net-shape or mesh-shaped components with all of these performance attributes. Plastic components eliminate corrosion and bi-metal anodic reactions under electrolytic conditions such as autoclaving, steam sterilizations and cleaning Press fits with lubricious plastics and materials also eliminate clearances with minimal strain or functional penalties on the components when compared to similar metal components. 
     Suitable materials for forming the components of the control assembly  107  include, but are not limited to, polyamines, polyphenylene sulfides, polyphthalamides, polyphenylsulfones, polyether ketones, polytetrafluoroethylenes, and combinations thereof. These components may be used in the presence or absence of lubricants and may also include additives for reduced wear and frictional forces. 
     Reference may be made to a U.S. patent application Ser. No. 13/331,047, now U.S. Pat. No. 8,968,276, the entire contents of which are incorporated by reference herein, for a detailed discussion of the construction and operation of the surgical instrument  100 . 
     The surgical instrument  100  includes a firing assembly configured to deploy or eject a plurality of staples into tissue captured by the end effector  300 . The firing assembly comprises a drive assembly  360 , as illustrated in  FIG. 9 . The drive assembly  360  includes a flexible drive beam  364  having a distal end which is secured to a dynamic clamping member  365 , and a proximal engagement section  368 . Engagement section  368  includes a stepped portion defining a shoulder  370 . A proximal end of engagement section  368  includes diametrically opposed inwardly extending fingers  372 . Fingers  372  engage a hollow drive member  374  to fixedly secure drive member  374  to the proximal end of beam  364 . Drive member  374  defines a proximal porthole  376   a  which receives a connection member of drive tube  246  ( FIG. 1 ) of adapter  200  when end effector  300  is attached to distal coupling  230  of adapter  200 . 
     When drive assembly  360  is advanced distally within tool assembly  304 , an upper beam  365   a  of clamping member  365  moves within a channel defined between anvil plate  312  and anvil cover  310  and a lower beam  365   b  moves over the exterior surface of carrier  316  to close tool assembly  304  and fire staples therefrom. 
     Proximal body portion  302  of end effector  300  includes a sheath or outer tube  301  enclosing an upper housing portion  301   a  and a lower housing portion  301   b.  The housing portions  301   a  and  301   b  enclose an articulation link  366  having a hooked proximal end  366   a  which extends from a proximal end of end effector  300 . Hooked proximal end  366   a  of articulation link  366  engages a coupling hook (not shown) of adapter  200  when end effector  300  is secured to distal housing  232  of adapter  200 . When drive bar  258  of adapter  200  is advanced or retracted as described above, articulation link  366  of end effector  300  is advanced or retracted within end effector  300  to pivot tool assembly  304  in relation to a distal end of proximal body portion  302 . 
     As illustrated in  FIG. 9  above, cartridge assembly  308  of tool assembly  304  includes a staple cartridge  305  supportable in carrier  316 . The cartridge can be permanently installed in the end effector  300  or can be arranged so as to be removable and replaceable. Staple cartridge  305  defines a central longitudinal slot  305   a,  and three linear rows of staple retention slots  305   b  positioned on each side of longitudinal slot  305   a.  Each of staple retention slots  305   b  receives a single staple  307  and a portion of a staple pusher  309 . During operation of instrument  100 , drive assembly  360  abuts an actuation sled and pushes actuation sled through cartridge  305 . As the actuation sled moves through cartridge  305 , cam wedges of the actuation sled sequentially engage staple pushers  309  to move staple pushers  309  vertically within staple retention slots  305   b  and sequentially eject staples  307  therefrom for formation against anvil plate  312 . 
     The hollow drive member  374  includes a lockout mechanism  373  that prevents a firing of previously fired end effectors  300 . The lockout mechanism  373  includes a locking member  371  pivotally coupled within a distal porthole  376   b  via a pin  377 , such that locking member  371  is pivotal about pin  377  relative to drive member  374 . 
     With reference to  FIGS. 10A and 10B , locking member  371  defines a channel  379  formed between elongate glides  381  and  383 . Web  385  joins a portion of the upper surfaces of glides  381  and  383 . Web  385  is configured and dimensioned to fit within the porthole  376   b  of the drive member  374 . Horizontal ledges  389  and  391  extend from glides  381  and  383  respectively. As best shown in  FIG. 9 , a spring  393  is disposed within the drive member  374  and engages horizontal ledge  389  and/or horizontal ledge  391  to bias locking member  371  downward. 
     In operation, the locking member  371  is initially disposed in its pre-fired position at the proximal end of the housing portions  301   a  and  301   b  with horizontal ledge  389  and  391  resting on top of projections  303   a,    303   b  formed in the sidewalls of housing portion  301   b.  In this position, locking member  371  is held up and out of alignment with a projection  303   c  formed in the bottom surface of housing portion  301   b,  distal of the projection  303   a,    303   b,  and web  385  is in longitudinal juxtaposition with shoulder  370  defined in drive beam  364 . This configuration permits the anvil  306  to be opened and repositioned onto the tissue to be stapled until the surgeon is satisfied with the position without activating locking member  371  to disable the disposable end effector  300 . 
     Upon distal movement of the drive beam  364  by the drive tube  246 , locking member  371  rides off of projections  303   a,    303   b  and is biased into engagement with housing portion  301   b  by the spring  393 , distal of projection  303   c.  Locking member  371  remains in this configuration throughout firing of the apparatus. 
     Upon retraction of the drive beam  364 , after at least a partial firing, locking member  371  passes under projections  303   a,    303   b  and rides over projection  303   c  of housing portion  301   b  until the distal-most portion of locking member  371  is proximal to projection  303   c.  The spring  393  biases locking member  371  into juxtaposed alignment with projection  303   c,  effectively disabling the disposable end effector when an attempt is made to reactuate the apparatus, loaded with the existing end effector  300 , the locking member  371  will abut projection  303   c  of housing portion  301   b  and will inhibit distal movement of the drive beam  364 . 
     Another aspect of the instrument  100  is shown in  FIG. 11 . The instrument  100  includes the motor  164 . The motor  164  may be any electrical motor configured to actuate one or more drives (e.g., rotatable drive connectors  118 ,  120 ,  122  of  FIG. 6 ). The motor  164  is coupled to the battery  156 , which may be a DC battery (e.g., rechargeable lead-based, nickel-based, lithium-ion based, battery etc.), an AC/DC transformer, or any other power source suitable for providing electrical energy to the motor  164 . 
     The battery  156  and the motor  164  are coupled to a motor driver circuit  404  disposed on the circuit board  154  which controls the operation of the motor  164  including the flow of electrical energy from the battery  156  to the motor  164 . The driver circuit  404  includes a plurality of sensors  408   a,    408   b,  . . .  408   n  configured to measure operational states of the motor  164  and the battery  156 . The sensors  408   a - n  may include voltage sensors, current sensors, temperature sensors, pressure sensors, telemetry sensors, optical sensors, and combinations thereof. The sensors  408   a - 408   n  may measure voltage, current, and other electrical properties of the electrical energy supplied by the battery  156 . The sensors  408   a - 408   n  may also measure rotational speed as revolutions per minute (RPM), torque, temperature, current draw, and other operational properties of the motor  164 . RPM may be determined by measuring the rotation of the motor  164 . Position of various drive shafts (e.g., rotatable drive connectors  118 ,  120 ,  122  of  FIG. 6 ) may be determined by using various linear sensors disposed in or in proximity to the shafts or extrapolated from the RPM measurements. In aspects, torque may be calculated based on the regulated current draw of the motor  164  at a constant RPM. In further aspects, the driver circuit  404  and/or the controller  406  may measure time and process the above-described values as a function thereof, including integration and/or differentiation, e.g., to determine rate of change of the measured values and the like. 
     The driver circuit  404  is also coupled to a controller  406 , which may be any suitable logic control circuit adapted to perform the calculations and/or operate according to a set of instructions. The controller  406  may include a central processing unit operably connected to a memory which may include transitory type memory (e.g., RAM) and/or non-transitory type memory (e.g., flash media, disk media, etc.). The controller  406  includes a plurality of inputs and outputs for interfacing with the driver circuit  404 . In particular, the controller  406  receives measured sensor signals from the driver circuit  404  regarding operational status of the motor  164  and the battery  156  and, in turn, outputs control signals to the driver circuit  404  to control the operation of the motor  164  based on the sensor readings and specific algorithm instructions. The controller  406  is also configured to accept a plurality of user inputs from a user interface (e.g., switches, buttons, touch screen, etc. of the control assembly  107  coupled to the controller  406 ). A removable memory card or chip may be provided, or data can be downloaded wirelessly. 
     Referring to  FIG. 12-18 , a surgical system  10 ′ is depicted. The surgical system  10 ′ is similar in many respects to the surgical system  10 . For example, the surgical system  10 ′ includes the surgical instrument  100 . Upper housing portion  108  of instrument housing  102  defines a nose or connecting portion  108   a  configured to accept a corresponding shaft coupling assembly  514  of a transmission housing  512  of a shaft assembly  500  that is similar in many respects to the shaft assembly  200 . 
     The shaft assembly  500  has a force transmitting assembly for interconnecting the at least one drive member of the surgical instrument to at least one rotation receiving member of the end effector. The force transmitting assembly has a first end that is connectable to the at least one rotatable drive member and a second end that is connectable to the at least one rotation receiving member of the end effector. When shaft assembly  500  is mated to surgical instrument  100 , each of rotatable drive members or connectors  118 ,  120 ,  122  of surgical instrument  100  couples with a corresponding rotatable connector sleeve  518 ,  520 ,  522  of shaft assembly  500  (see  FIGS. 13 and 15 ). In this regard, the interface between corresponding first drive member or connector  118  and first connector sleeve  518 , the interface between corresponding second drive member or connector  120  and second connector sleeve  520 , and the interface between corresponding third drive member or connector  122  and third connector sleeve  522  are keyed such that rotation of each of drive members or connectors  118 ,  120 ,  122  of surgical instrument  100  causes a corresponding rotation of the corresponding connector sleeve  518 ,  520 ,  522  of shaft assembly  500 . 
     The selective rotation of drive member(s) or connector(s)  118 ,  120  and/or  122  of surgical instrument  100  allows surgical instrument  100  to selectively actuate different functions of an end effector  400 . 
     Referring to  FIGS. 12 and 14 , the shaft assembly  500  includes an elongate, substantially rigid, outer tubular body  510  having a proximal end  510   a  and a distal end  510   b  and a transmission housing  212  connected to proximal end  210   a  of tubular body  510  and being configured for selective connection to surgical instrument  100 . In addition, the shaft assembly  500  further includes an articulating neck assembly  530  connected to distal end  510   b  of elongate body portion  510 . 
     Transmission housing  512  is configured to house a pair of gear train systems therein for varying a speed/force of rotation (e.g., increase or decrease) of first, second and/or third rotatable drive members or connectors  118 ,  120 , and/or  122  of surgical instrument  100  before transmission of such rotational speed/force to the end effector  501 . As seen in  FIG. 15 , transmission housing  512  and shaft coupling assembly  514  rotatably support a first proximal or input drive shaft  524   a,  a second proximal or input drive shaft  526   a,  and a third drive shaft  528 . 
     Shaft drive coupling assembly  514  includes a first, a second and a third biasing member  518   a,    520   a  and  522   a  disposed distally of respective first, second and third connector sleeves  518 ,  520 ,  522 . Each of biasing members  518   a,    520   a  and  522   a  is disposed about respective first proximal drive shaft  524   a,  second proximal drive shaft  526   a,  and third drive shaft  228 . Biasing members  518   a,    520   a  and  522   a  act on respective connector sleeves  518 ,  520  and  522  to help maintain connector sleeves  218 ,  220  and  222  engaged with the distal end of respective drive rotatable drive members or connectors  118 ,  120 ,  122  of surgical instrument  100  when shaft assembly  500  is connected to surgical instrument  100 . 
     Shaft assembly  500  includes a first and a second gear train system  540 ,  550 , respectively, disposed within transmission housing  512  and tubular body  510 , and adjacent coupling assembly  514 . As mentioned above, each gear train system  540 ,  550  is configured and adapted to vary a speed/force of rotation (e.g., increase or decrease) of first and second rotatable drive connectors  118  and  120  of surgical instrument  100  before transmission of such rotational speed/force to end effector  501 . 
     As illustrated in  FIGS. 15 and 16 , first gear train system  540  includes first input drive shaft  524   a,  and a first input drive shaft spur gear  542   a  keyed to first input drive shaft  524   a.  First gear train system  540  also includes a first transmission shaft  544  rotatably supported in transmission housing  512 , a first input transmission spur gear  544  a keyed to first transmission shaft  544  and engaged with first input drive shaft spur gear  542   a,  and a first output transmission spur gear  544   b  keyed to first transmission shaft  544 . First gear train system  540  further includes a first output drive shaft  546   a  rotatably supported in transmission housing  512  and tubular body  510 , and a first output drive shaft spur gear  546   b  keyed to first output drive shaft  546   a  and engaged with first output transmission spur gear  544   b.    
     In at least one instance, the first input drive shaft spur gear  542   a  includes 10 teeth; first input transmission spur gear  544   a  includes 18 teeth; first output transmission spur gear  544   b  includes 13 teeth; and first output drive shaft spur gear  546   b  includes 15 teeth. As so configured, an input rotation of first input drive shaft  524   a  is converted to an output rotation of first output drive shaft  546   a  by a ratio of 1:2.08. 
     In operation, as first input drive shaft spur gear  542   a  is rotated, due to a rotation of first connector sleeve  558  and first input drive shaft  524   a,  as a result of the rotation of the first respective drive connector  118  of surgical instrument  100 , first input drive shaft spur gear  542   a  engages first input transmission spur gear  544   a  causing first input transmission spur gear  544   a  to rotate. As first input transmission spur gear  544   a  rotates, first transmission shaft  544  is rotated and thus causes first output drive shaft spur gear  546   b,  that is keyed to first transmission shaft  544 , to rotate. As first output drive shaft spur gear  546   b  rotates, since first output drive shaft spur gear  546   b  is engaged therewith, first output drive shaft spur gear  546   b  is also rotated. As first output drive shaft spur gear  546   b  rotates, since first output drive shaft spur gear  546   b  is keyed to first output drive shaft  546   a,  first output drive shaft  546   a  is rotated. 
     The shaft assembly  500 , including the first gear system  540 , functions to transmit operative forces from surgical instrument  100  to end effector  501  in order to operate, actuate and/or fire end effector  501 . 
     As illustrated in  FIGS. 15 and 17 , second gear train system  550  includes second input drive shaft  526   a,  and a second input drive shaft spur gear  552   a  keyed to second input drive shaft  526   a.  Second gear train system  550  also includes a first transmission shaft  554  rotatably supported in transmission housing  512 , a first input transmission spur gear  554   a  keyed to first transmission shaft  554  and engaged with second input drive shaft spur gear  552   a,  and a first output transmission spur gear  554   b  keyed to first transmission shaft  554 . 
     Second gear train system  550  further includes a second transmission shaft  556  rotatably supported in transmission housing  512 , a second input transmission spur gear  556   a  keyed to second transmission shaft  556  and engaged with first output transmission spur gear  554   b  that is keyed to first transmission shaft  554 , and a second output transmission spur gear  556   b  keyed to second transmission shaft  556 . 
     Second gear train system  550  additionally includes a second output drive shaft  558   a  rotatably supported in transmission housing  512  and tubular body  510 , and a second output drive shaft spur gear  558   b  keyed to second output drive shaft  558   a  and engaged with second output transmission spur gear  556   b.    
     In at least one instance, the second input drive shaft spur gear  552   a  includes 10 teeth; first input transmission spur gear  554   a  includes 20 teeth; first output transmission spur gear  554   b  includes 10 teeth; second input transmission spur gear  556   a  includes 20 teeth; second output transmission spur gear  556   b  includes 10 teeth; and second output drive shaft spur gear  558   b  includes 15 teeth. As so configured, an input rotation of second input drive shaft  526   a  is converted to an output rotation of second output drive shaft  558   a  by a ratio of 1:6. 
     In operation, as second input drive shaft spur gear  552   a  is rotated, due to a rotation of second connector sleeve  560  and second input drive shaft  526   a,  as a result of the rotation of the second respective drive connector  120  of surgical instrument  100 , second input drive shaft spur gear  552   a  engages first input transmission spur gear  554   a  causing first input transmission spur gear  554   a  to rotate. As first input transmission spur gear  554   a  rotates, first transmission shaft  554  is rotated and thus causes first output transmission spur gear  554   b,  that is keyed to first transmission shaft  554 , to rotate. As first output transmission spur gear  554   b  rotates, since second input transmission spur gear  556   a  is engaged therewith, second input transmission spur gear  556   a  is also rotated. As second input transmission spur gear  556   a  rotates, second transmission shaft  256  is rotated and thus causes second output transmission spur gear  256   b,  that is keyed to second transmission shaft  556 , to rotate. As second output transmission spur gear  556   b  rotates, since second output drive shaft spur gear  558   b  is engaged therewith, second output drive shaft spur gear  558   b  is rotated. As second output drive shaft spur gear  558   b  rotates, since second output drive shaft spur gear  558   b  is keyed to second output drive shaft  558   a,  second output drive shaft  558   a  is rotated. 
     The shaft assembly  500 , including second gear train system  550 , functions to transmit operative forces from surgical instrument  100  to end effector  501  in order rotate shaft assembly  500  and/or end effector  501  relative to surgical instrument  100 . 
     As illustrated in  FIGS. 15 and 18 , the transmission housing  512  and shaft coupling assembly  514  rotatably support a third drive shaft  528 . Third drive shaft  528  includes a proximal end  528   a  configured to support third connector sleeve  522 , and a distal end  528   b  extending to and operatively connected to an articulation assembly  570 . 
     As illustrated in  FIG. 14 , elongate, outer tubular body  510  of shaft assembly  500  includes a first half section  511  a and a second half section  511   b  defining at least three longitudinally extending channels through outer tubular body  510  when half sections  511   a,    511   b  are mated with one another. The channels are configured and dimensioned to rotatably receive and support first output drive shaft  546   a,  second output drive shaft  558   a,  and third drive shaft  528  as first output drive shaft  546   a,  second output drive shaft  558   a,  and third drive shaft  528  extend from transmission housing  512  to articulating neck assembly  530 . Each of first output drive shaft  546   a,  second output drive shaft  558   a,  and third drive shaft  528  are elongate and sufficiently rigid to transmit rotational forces from transmission housing  520  to articulating neck assembly  530 . 
     Turning to  FIG. 14 , the shaft assembly  500  further includes an articulating neck assembly  530 . The articulating neck assembly  530  includes a proximal neck housing  532 , a plurality of links  534  connected to and extending in series from proximal neck housing  532 ; and a distal neck housing  536  connected to and extending from a distal-most link of the plurality of links  534 . It is contemplated that, in any of the aspects disclosed herein, that the shaft assembly may have a single link or pivot member for allowing the articulation of the end effector. It is contemplated that, in any of the aspects disclosed herein, that the distal neck housing can be incorporated with the distal most link. 
     The entire disclosures of: 
     U.S. Patent Application Publication No. 2014/0110453, filed Oct. 23, 2012, and titled SURGICAL INSTRUMENT WITH RAPID POST EVENT DETECTION, now U.S. Pat. No. 9,265,585; 
     U.S. Patent Application Publication No. 2013/0282052, filed Jun. 19, 2013, and titled APPARATUS FOR ENDOSCOPIC PROCEDURES, now U.S. Pat. No. 9,480,492; and 
     U.S. Patent Application Publication No. 2013/0274722, filed May 10, 2013, and titled APPARATUS FOR ENDOSCOPIC PROCEDURES, now U.S. Pat. No. 9,492,146, are hereby incorporated by reference herein. 
     Referring to  FIGS. 19-20 , a surgical instrument  10  is depicted. The surgical instrument  10  is similar in many respects to the surgical instrument  100 . For example, the surgical instrument  10  is configured for selective connection with the end effector or single use loading unit or reload  300  via the adapter  200 . Also, the surgical instrument  10  includes a handle housing  102  that includes a lower housing portion  104 , an intermediate housing portion  106 , and an upper housing portion  108 . 
     Like the surgical instrument  100 , the surgical instrument  10  includes a drive mechanism  160  which is configured to drive shafts and/or gear components in order to perform the various operations of surgical instrument  10 . In at least one instance, the drive mechanism  160  includes a rotation drivetrain  12  (See  FIG. 20 ) configured to rotate end effector  300  about a longitudinal axis “X” (see  FIG. 2 ) relative to handle housing  102 . The drive mechanism  160  further includes a closure drivetrain  14  (See  FIG. 20 ) configured to move the anvil assembly  306  relative to the cartridge assembly  308  of the end effector  300  to capture tissue therebetween. In addition, the drive mechanism  160  includes a firing drivetrain  16  (See  FIG. 20 ) configured to fire a stapling and cutting cartridge within the cartridge assembly  308  of the end effector  300 . 
     As described above, referring primarily to  FIGS. 7, 8, and 20 , the drive mechanism  160  includes a selector gearbox assembly  162  that can be located immediately proximal relative to adapter  200 . Proximal to the selector gearbox assembly  162  is the function selection module  163  which includes the first motor  164  that functions to selectively move gear elements within the selector gearbox assembly  162  to selectively position one of the drivetrains  12 ,  14 , and  16  into engagement with the input drive component  165  of the second motor  166 . 
     Referring to  FIG. 20 , the motors  164  and  166  are coupled to motor control circuits  18  and  18 ′, respectively, which are configured to control the operation of the motors  164  and  66  including the flow of electrical energy from a power source  156  to the motors  164  and  166 . The power source  156  may be a DC battery (e.g., rechargeable lead-based, nickel-based, lithium-ion based, battery etc.), an AC/DC transformer, or any other power source suitable for providing electrical energy to the surgical instrument  10 . 
     The surgical instrument  10  further includes a microcontroller  20  (“controller”). In certain instances, the controller  20  may include a microprocessor  36  (“processor”) and one or more computer readable mediums or memory units  38  (“memory”). In certain instances, the memory  38  may store various program instructions, which when executed may cause the processor  36  to perform a plurality of functions and/or calculations described herein. The power source  156  can be configured to supply power to the controller  20 , for example. 
     The processor  36  can be in communication with the motor control circuit  18 . In addition, the memory  38  may store program instructions, which when executed by the processor  36  in response to a user input  34 , may cause the motor control circuit  18  to motivate the motor  164  to generate at least one rotational motion to selectively move gear elements within the selector gearbox assembly  162  to selectively position one of the drivetrains  12 ,  14 , and  16  into engagement with the input drive component  165  of the second motor  166 . Furthermore, the processor  36  can be in communication with the motor control circuit  18 ′. The memory  38  may also store program instructions, which when executed by the processor  36  in response to a user input  34 , may cause the motor control circuit  18 ′ to motivate the motor  166  to generate at least one rotational motion to drive the drivetrain engaged with the input drive component  165  of the second motor  166 , for example. 
     The controller  20  and/or other controllers of the present disclosure may be implemented using integrated and/or discrete hardware elements, software elements, and/or a combination of both. Examples of integrated hardware elements may include processors, microprocessors, microcontrollers, integrated circuits, ASICs, PLDs, DSPs, FPGAs, logic gates, registers, semiconductor devices, chips, microchips, chip sets, microcontrollers, SoC, and/or SIP. Examples of discrete hardware elements may include circuits and/or circuit elements such as logic gates, field effect transistors, bipolar transistors, resistors, capacitors, inductors, and/or relays. In certain instances, the controller  20  may include a hybrid circuit comprising discrete and integrated circuit elements or components on one or more substrates, for example. 
     In certain instances, the controller  20  and/or other controllers of the present disclosure may be an LM 4F230H5QR, available from Texas Instruments, for example. In certain instances, the Texas Instruments LM4F230H5QR is an ARM Cortex-M 4 F Processor Core comprising on-chip memory of 256 KB single-cycle flash memory, or other non-volatile memory, up to 40 MHz, a prefetch buffer to improve performance above 40 MHz, a 32 KB single-cycle SRAM, internal ROM loaded with StellarisWare® software, 2 KB EEPROM, one or more PWM modules, one or more QEI analog, one or more 12-bit ADC with 12 analog input channels, among other features that are readily available. Other microcontrollers may be readily substituted for use with the present disclosure. Accordingly, the present disclosure should not be limited in this context. 
     In various instances, one or more of the various steps described herein can be performed by a finite state machine comprising either a combinational logic circuit or a sequential logic circuit, where either the combinational logic circuit or the sequential logic circuit is coupled to at least one memory circuit. The at least one memory circuit stores a current state of the finite state machine. The combinational or sequential logic circuit is configured to cause the finite state machine to the steps. The sequential logic circuit may be synchronous or asynchronous. In other instances, one or more of the various steps described herein can be performed by a circuit that includes a combination of the processor  36  and the finite state machine, for example. 
     In various instances, it can be advantageous to be able to assess the state of the functionality of a surgical instrument to ensure its proper function. It is possible, for example, for the drive mechanism, as explained above, which is configured to include various motors, drivetrains, and/or gear components in order to perform the various operations of the surgical instrument  10 , to wear out over time. This can occur through normal use, and in some instances the drive mechanism can wear out faster due to abuse conditions. In certain instances, a surgical instrument  10  can be configured to perform self-assessments to determine the state, e.g. health, of the drive mechanism and it various components. 
     For example, the self-assessment can be used to determine when the surgical instrument  10  is capable of performing its function before a re-sterilization or when some of the components should be replaced and/or repaired. Assessment of the drive mechanism and its components, including but not limited to the rotation drivetrain  12 , the closure drivetrain  14 , and/or the firing drivetrain  16 , can be accomplished in a variety of ways. The magnitude of deviation from a predicted performance can be used to determine the likelihood of a sensed failure and the severity of such failure. Several metrics can be used including: Periodic analysis of repeatably predictable events, Peaks or drops that exceed an expected threshold, and width of the failure. 
     In various instances, a signature waveform of a properly functioning drive mechanism or one or more of its components can be employed to assess the state of the drive mechanism or the one or more of its components. One or more vibration sensors can be arranged with respect to a properly functioning drive mechanism or one or more of its components to record various vibrations that occur during operation of the properly functioning drive mechanism or the one or more of its components. The recorded vibrations can be employed to create the signature waveform. Future waveforms can be compared against the signature waveform to assess the state of the drive mechanism and its components. 
     In at least one aspect, the principles of acoustics can be employed to assess the state of the drive mechanism and its components. As used herein, the term acoustics refers generally to all mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound (sound waves with frequencies higher than the upper audible limit of human hearing), and infrasound (low-frequency sound, lower in frequency than 20 Hz [hertz] or cycles per second, hence lower than the “normal” limit of human hearing). Accordingly, acoustic emissions from the drive mechanism and its components may be detected with acoustic sensors including vibration, sound, ultrasound, and infrasound sensors. In one aspect, the vibratory frequency signature of a drive mechanism  160  can be analyzed to determine the state of one or more of the drivetrains  12 ,  14 , and/or  16 . One or more vibration sensors can be coupled to one or more of the drivetrains  12 ,  14 , and/or  16  in order to record the acoustic output of the drivetrains when in use. 
     Referring again to  FIG. 20 , the surgical instrument  10  includes a drivetrain failure detection module  40  configured to record and analyze one or more acoustic outputs of one or more of the drivetrains  12 ,  14 , and/or  16 . The processor  36  can be in communication with or otherwise control the module  40 . As described below in greater detail, the module  40  can be embodied as various means, such as circuitry, hardware, a computer program product comprising a computer readable medium (for example, the memory  38 ) storing computer readable program instructions that are executable by a processing device (for example, the processor  36 ), or some combination thereof. In some aspects, the processor  36  can include, or otherwise control the module  40 . 
     The module  40  may include one or more sensors  42  can be employed by the module  40  to detect drivetrain failures of the surgical instrument  10 . In at least one instance, as illustrated in  FIG. 21 , the sensors  42  may comprise one or more acoustic sensors or microphones, for example. In at least one instance, as illustrated in  FIG. 24 , the sensors  42  may comprise one or more accelerometers. 
     Various types of filters and transforms can be used on the output of a sensor  42  to generate a waveform that represents the operational state of a drivetrain, for example, of the surgical instrument  10 . As illustrated in  FIG. 21 , a plurality of Band-pass filters can be configured to communicate with a sensor  42  in order to process an output thereof. In the example shown in  FIG. 21 , there are four Band-pass filters, BPF 1 , BPF 2 , BPF 3 , and BPF 4 , used to filter the output of the sensor  42 . These filters are used to determine the various thresholds used to assess the health of a surgical instrument  10 , including acceptable limits, marginal limits, and critical limits, for example. In one example, a series of low pass filters as illustrated in  FIG. 24  can be used on the output of the sensor  42 . 
     In one aspect, as illustrated in  FIG. 21 , logic gates can be employed with the filters to process the output of the sensors  42 . Alternatively, a processor such as, for example, the processor  36  can be employed with the filters to process the output of the sensors  42 , as illustrated in  FIGS. 24 and 24A .  FIGS. 24B, 24C, and 24D  depict an example structure and operational details of a Band-pass filter used to filter the output of the sensor  42 . In at least one instance, one or more of the filters employed in filtering the output the sensor  42  is a Dual Low-Noise JFET-Input General-Purpose Operational Amplifier. 
     While various frequencies can be used, the exemplary frequencies of the filters shown in  FIG. 21  are 5 kHz, 1 kHz, 200 Hz, and 50 Hz. The output of each filter is shown in  FIG. 25 , which illustrates the voltage amplitude at the frequency of each filter. The peak amplitude of the output of each filter is shown in  FIG. 26 . These values can be used to determine the health of the surgical instrument  10  by comparison against threshold values stored in the memory  38 , for example. As illustrated in  FIG. 24 , a multiplexer  44  and an analogue to digital converter  46  can be employed to communicate the output of the filters to the processor  36 . 
     In at least one instance, an output of a sensor  42  can be recorded when a motor is running during a known function having repeatable movement. For example, the output can be recorded when the motor  166  is running to retract or reset a drivetrain such as, for example the firing drivetrain  16  to an original or starting position. The recorded output of the sensor  42  can be used to develop a signature waveform of that movement. In one example, the recorded output of the sensor  42  is run through a fast Fourier transform to develop the signature waveform. 
     Further to the above, the amplitude of key regions of the resulting signature waveform can be compared to predetermined values stored in the memory  38 , for example. In at least one instance, the memory  38  may include program instructions which, when executed by the processor  36 , may cause the processor  36  to compare the amplitudes of the key regions to the predetermined values stored in the memory  38 . When the amplitudes exceed those stored values, the processor  36  determines that one or more components of the surgical instrument  10  is no longer functioning properly and/or that the surgical instrument  10  has reached the end of its usable life. 
       FIG. 22  illustrates a vibratory response from a drivetrain that is functioning properly. The output in volts from a microphone that is positioned on or in close proximity to the drivetrain is recorded over time. The frequency response of that output is determined using a fast Fourier transform, as shown in  FIG. 22A , to develop a signature waveform for a properly functioning drivetrain. The signature waveform of the properly functioning drivetrain can be employed to detect any malfunction in the same drivetrain or other similar drivetrains. For example,  FIG. 23  illustrates a vibratory response from a drivetrain that is not functioning properly. The microphone output is used to determine the frequency response of the malfunctioning drivetrain, as illustrated in  FIG. 23A . The deviation of the frequency response of the malfunctioning drivetrain from the signature waveform of the properly functioning drivetrain indicates a malfunction in the drivetrain. 
     In at least one instance, stored values of key regions of a frequency response of a properly functioning drivetrain, as shown in  FIG. 22A , are compared against recorded values of corresponding regions of a frequency response of an examined drivetrain, as shown in  FIG. 23A . In the event the stored values are exceeded by the recorded values, it can be concluded that a malfunction is detected in the examined drivetrain. In response, various safety and remedial steps can be taken as described in greater detail in commonly-owned U.S. patent application Ser. No. 14/984,525, titled MECHANISMS FOR COMPENSATING FOR DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, and filed Dec. 30, 2015, now U.S. Pat. No. 10,368,865, which is incorporated herein by reference in their entireties. 
     There can be various stages of operation of the surgical instrument  10  as the components are moved to effect a function at an end effector of the surgical instrument  10  such as, for example capturing tissue, firing staples into the captured tissue, and/or cutting the captured tissue. The vibrations generated by the drive mechanism  160  of the surgical instrument  10  can vary depending on the stage of operation of the surgical instrument  10 . Certain vibrations can be uniquely associated with certain stages of operation of the surgical instrument  10 . Accordingly, taking into consideration the stage or zone of operation of the surgical instrument  10  allows for selectively analyzing the vibrations that are associated with that stage or zone of operation while ignoring other vibrations that are not relevant to that stage or zone of operation. Various sensors such as, for example, position sensors can be employed by the processor  36  to determine the stage of operation of the surgical instrument  10 . 
     In one example, various stages of operation of the instrument  10  are represented in the graph of  FIG. 27 , which illustrates the force needed to fire (FTF) the surgical instrument  10  in relation to a displacement position of the drive assembly  360  from a starting or original position during a firing sequence or stroke of the surgical instrument  10 . In zone  1 , an end effector  300  of the surgical instrument  10  has clamped onto tissue, as described above, but has not affected the tissue. In zone  2 , a load is being applied to move an actuation sled of the surgical instrument  10  to allow the end effector  300  to affect the tissue by, for example, cutting and stapling the tissue. In zone  3 , the tissue has been cut and stapled by the end effector  300  of the surgical instrument  10 . Depending on which zone the surgical instrument  10  is in during capture and processing of the vibrations made by the various drivetrains, the vibrations can either be compared to threshold frequency values or can be disregarded or not considered. For vibrations captured by a sensor  42  in block  48  and block  50  of  FIG. 27 , certain portions of the captured vibrations can be disregarded or not considered for the purposes of determining the health of the surgical instrument  10 . 
     In at least one instance, any vibrations captured below the threshold line  52  can be disregarded or not considered. In at least one instance, the ratio of the minimum threshold  52  to a maximum FTF during a firing sequence or stroke of the surgical instrument  10  is any value selected from a range of about 0.001 to about 0.30, for example. In at least one instance, the ratio is any value selected from a range of about 0.01 to about 0.20, for example. In at least one instance, the ratio is any value selected from a range of about 0.01 to about 0.10, for example. 
     In addition, any vibrations captured within the block  48  and block  50  can also be disregarded or not considered as long as the events within those blocks are not a catastrophic event. In the event of a catastrophic failure, a drive mechanism  160  is rendered inoperable, and certain bailout steps are taken to ensure, among other things, a safe detachment of the surgical instrument  10  from the tissue being treated. Alternatively, In the event of an acute drivetrain failure, the drivetrain may still be operated to complete a surgical step or to reset the surgical instrument  10 ; however, certain precautionary and/or safety steps can be taken to avoid or minimize additional damage to the drivetrain and/or other components of the surgical instrument  10 . 
     Referring again to  FIG. 27 , in at least one instance, vibrations detected at the beginning and/or the end of the firing stroke of the surgical instrument  10  are disregarded or not considered for the purposes of assessing a damage/function status of the surgical instrument  10 . In one example, only vibrations detected at a central segment of the firing stroke of the surgical instrument  10  are considered for the purposes of assessing a damage/function status of the surgical instrument  10 . In at least one instance, vibrations detected at the beginning of zone  1  and/or at the end of  2 one  2  of the firing stroke of the surgical instrument  10 , as illustrated in  FIG. 27 , are disregarded or not considered for the purposes of assessing a damage/function status of the surgical instrument  10 . 
     A limited increase in noise could indicate increased wear or a non-catastrophic failure of parts of the gears, for example. A significant increase in the magnitude of the noise in chronic fashion could indicate continuing erosion of the transmission but could be used to predict the life of the instrument  10  and it performance degradation allowing the completion of certain jobs, for example. An acute dramatic increase in magnitude or number of peaks could indicate a substantial or catastrophic failure causing the instrument to initiate more immediate and final reaction options, for example. 
       FIG. 28  illustrates the velocity of the drive assembly  360  of the surgical instrument  10  in relation to a displacement position of the drive assembly  360  from a starting or original position. Point A, shown in  FIGS. 27 and 28 , represents an initial contact with tissue, increasing the force to advance the drive assembly  360  of the surgical instrument  10 , as shown in  FIG. 27 , and decreasing the velocity of drive assembly  360 , as shown in  FIG. 28 . Point B, also shown in  FIGS. 27 and 28 , represents a contact with the thickest portion of the tissue during the stapling and cutting. Accordingly, the FTF at point B is at maximum, as shown in  FIG. 27 , and the velocity at point B is at its lowest point, as shown in  FIG. 28 . One or more sensors such as, for example, force sensors can be configured to measure the FTF as the drive assembly  360  is advanced. In addition, one or more position sensors can be configured to detect the position of the drive assembly  360  during a firing sequence of the surgical instrument  10 . 
     In at least one instance, the memory  38  includes program instructions which, when executed by the processor  36 , causes the processor  36  to employ one or more sensors  42  positioned near one or more components of the drive mechanism  160  of the surgical instrument  10  to selectively capture or record vibrations generated by the one or more components of the drive mechanism  160  during a predetermined section of the firing sequence. In at least one instance, the sensors  42  are activated by the processor  36  at a starting point of the predetermined section and deactivated at an end point of the predetermined section of the firing sequence or stroke so that the sensors  42  may only capture or record vibrations generated by during the predetermined section. 
     The predetermined section may have a starting point after the firing sequence is begun and an end point before the firing sequence is completed. Said another way, the processor  36  is configured to cause the sensors  42  to only record vibrations at a central section of the firing sequence. As illustrated in  FIG. 28 , the processor  36  can be configured to cause the sensors  42  to start capturing or recording vibrations during a downward slope of the velocity of the drive assembly  360 , and stop recording vibrations during an upward slope of the velocity of the drive assembly  360 . Alternatively, the sensors  42  can be active during the entire firing sequence of the surgical instrument  10  while the processor  36  ignores or excludes vibrations recorded outside the predetermined section of the firing sequence or stroke. 
       FIG. 29  illustrates acceptable limit modifications based on the zone of the stroke location. Limit profiles for both zone  1  and zone  2  are shown. The threshold limits for zone  2  are higher than zone  1  due to the load of the tissue on the surgical instrument  10 . As the velocity of the instrument decreases as the instrument moves from zone  1  to zone  2 , the power spectrum will shift down in frequency. As shown in  FIG. 30 , which represents voltage amplitude versus frequency at various bandwidth represented by the filters shown in  FIG. 24  for points A and B of  FIGS. 27 and 28 , the frequency lines associated with point B for each filter bandwidth are lower than the frequency lines associated with point A due to the load on the instrument  10  from the tissue at point B and the velocity change due to the stroke zone. 
     Thus, these limits can be used to assess potential damage to the surgical instrument  10 . Using the captured vibrations from the various drivetrains of the surgical instrument  10 , the vibrations can be processed using the processor  36  shown in  FIG. 21  to determine when the frequency of the vibrations is above certain threshold values stored in memory  38  associated with the processor  36  while taking into account the zone of operation of the surgical instrument  10  during the time of the capture of the vibrations. When the surgical instrument  10  is determined to be defective in some way, the instrument  10  can be repaired or replaced before sterilization or its subsequent use. Various other safety and/or remedial steps can also be taken. 
     In another aspect, the magnitude of the noise produced by the surgical instrument  10  can be compared to predefined system harmonics to assess potential damage to the surgical instrument  10 , and the severity of that damage. As shown in  FIG. 31 , the output from the sensor  42  from one or more drivetrains of the surgical instrument  10  is presented as a voltage signal for zone  1 , for example. Each frequency, as captured during the processing of the signal through the filters, such as those shown in  FIG. 24 , can have its own threshold profile. 
     For example, as shown in  FIG. 31 , each frequency may have its own acceptable limit  54 , marginal limit  56 , and critical limit  58  for each zone of operation of the surgical instrument  10 . Based on the example shown in  FIG. 31 , all the frequencies are acceptable and represent a properly functioning surgical instrument  10  except for the frequency represented by A′. In at least one instance, this causes a processor, such as the processor  36  shown in  FIG. 24 , to conclude that an acute but not catastrophic drivetrain failure had occurred. 
     Further to the above, in at least one instance, the processor  36  is configured to conclude that a catastrophic drivetrain failure had occurred when any one frequency is equal to or exceeds the critical limit  58 . Alternatively, the processor  36  may be configured to conclude that a catastrophic drivetrain failure had occurred only when a plurality of frequencies is equal to or exceeds the critical limit  58 , for example. Alternatively, the processor  36  may be configured to conclude that a catastrophic drivetrain failure had occurred only when all frequencies, as captured during the processing of the signal through the filters, are equal to or exceed the critical limit  58 , for example. 
     Further to the above, in at least one instance, the processor  36  is configured to conclude that an acute drivetrain failure had occurred when any one frequency is equal to or exceeds the marginal limit  56  but is below the critical limit  58 , as illustrated in  FIG. 31 . Alternatively, the processor  36  may be configured to conclude that an acute drivetrain failure had occurred only when a plurality of frequencies is equal to or exceeds the marginal limit  56  but below the critical limit  58 , for example. Alternatively, the processor  36  may be configured to conclude that an acute drivetrain failure had occurred only when all frequencies, as captured during the processing of the signal through the filters, are equal to or exceed the marginal limit  56  but below the critical limit  58 , for example. 
     Referring to  FIG. 32 , a logic diagram  21  represents possible operations that can be implemented by the surgical instrument  10  in response to detected drivetrain failures. The memory  38  may include program instructions, which when executed by the processor  36 , may cause the processor  36  to assess the severity of a drivetrain failure based on input from the sensors  42 , and activate appropriate responses depending on the determined severity. The memory  38  may include program instructions, which when executed by the processor  36 , may cause the processor  36  to respond to a detected  23  acute drivetrain failure by activating a safe mode  22  of operation, for example. In addition, the memory  38  may include program instructions, which when executed by the processor  36 , may cause the processor  36  to respond to a detected catastrophic drivetrain failure by activating a recovery or bailout mode  22 . When no drivetrain failures are detected, the processor  36  may permit the surgical instrument  10  to continue  27  with normal operations until a drivetrain failure is detected. 
     Referring again to  FIG. 32 , the safe mode  22  may comprise one or more steps such as, for example, a motor modulation step which can be employed by the processor  36  to limit the speed of an active drivetrain. For example, when the firing drivetrain  16  is being actively driven by the motor  166  during a firing sequence, a detection of an acute drivetrain failure by the module  40  may cause the processor  36  to communicate to the motor drive circuit  18 ′ ( FIG. 20 ) instructions to cause the mechanical output of the motor  166  to be reduced. A reduction in the mechanical output of the motor  166  reduces the speed of the active drivetrain  16  which ensures safe completion of the firing sequence and/or resetting of the active drivetrain  16  to an original or starting position. 
     In another aspect, a frequency comparison of a cumulative magnitude of noise with respect to a predetermined minimum and/or maximum threshold is used to assess potential damage to the surgical instrument  10 . In at least one instance, a minimum threshold defines an acceptable limit  54 . A cumulative magnitude of noise that is below the minimum threshold is construed by the processor  36  as an acceptable limit  54 . In addition, a maximum threshold can be employed to define a critical limit  58 . A cumulative magnitude of noise that is above the minimum threshold is construed by the processor  36  as a critical limit  58 . A marginal limit  56  can be defined by the minimum and maximum thresholds. In one example, a cumulative magnitude of noise that is above the minimum threshold but below the maximum threshold is construed by the processor  36  as a marginal limit  56 . 
       FIG. 33  is a representation of a processed signal of the output of a sensor  42  that was filtered by four Band-pass filters, BPF 1 , BPF 2 , BPF 3 , and BPF 4 . The processed signal is represented within frequency bandwidths a 1 , a 2 , a 3 , and a 4  that correspond to the bandwidths of the four Band-pass filters, BPF 1 , BPF 2 , BPF 3 , and BPF 4 . 
       FIG. 33  illustrates a graph of voltage amplitude versus frequency of the processed signal. The peal voltage amplitudes of the processed signal at the center frequencies of the Band-pass filters, BPF 1 , BPF 2 , BPF 3 , and BPF 4  are represented by solid vertical lines A, A′, A″, and A′″, respectively. In addition, a baseline threshold value  60  is used to allow for a predictable amount of noise to be disregarded or not considered. Additional noise can be either taken into consideration or disregarded depending on where it falls in the frequency spectrum. 
     In the example illustrated in  FIG. 33 , the voltage amplitude Z 2  is discounted as it is below the baseline threshold value  60  that represented an acceptable level of noise, and Z 4  is discounted as it falls outside the predetermined bandwidths a 1 , a 2 , a 3 , and a 4 . As Z, Z 1 , and Z 3  fall above the baseline threshold value  60  and are within the predetermined bandwidths a 1 , a 2 , a 3 , and a 4 , these voltage amplitudes are considered with A, A′, A″, and A″′ in defining the cumulative magnitude of noise and, in turn, determining the potential damage to the instrument  10 . 
     In at least one instance, the Voltage amplitude values at the center frequencies A, A′, A″, and A″′ are summed to generate the cumulative magnitude of noise, as represented by voltage amplitude, that is then employed to assess whether a failure had occurred, and when so, the severity of that failure. In another instance, the Voltage amplitude values at the center frequencies A, A′, A″, and A″′ and any voltage amplitude within the predetermined bandwidths a 1 , a 2 , a 3 , and a 4  are summed to generate the cumulative magnitude of noise, as represented by voltage amplitude, that is then employed to assess whether a failure had occurred, and when so, the severity of that failure. In another instance, the Voltage amplitude values at the center frequencies A, A′, A″, and A″′ and any voltage amplitude values greater than the baseline threshold value  60  and within the predetermined bandwidths a 1 , a 2 , a 3 , and a 4  are summed to generate the cumulative magnitude of noise, as represented by voltage amplitude, that is then employed to assess whether a failure had occurred, and when so, the severity of that failure. 
     In various instances, a comparison between a present noise signal and a previously recorded noise signal, which may be stored in the memory  38 , can be employed by the processor  36  to determine a damage/function status of the surgical instrument  10 . A noise signal that is recorded by the sensor  42  during a normal operation of the surgical instrument  10  can be filtered and processed by the processor  36  to generate normal processed signal that is stored in the memory  38 . Any new noise signal recorded by the sensor  42  can be filtered and processed in the same manner as the normal noise signal to generate a present processed signal which can be compared to normal processed signal stored in the memory  38 . 
     A deviation between the present processed signature and the normal processed signal beyond a predetermined threshold can be construed as potential damage to the surgical instrument  10 . The normal processed signal can be set the first time the instrument is used, for example. Alternatively, a present processed signal becomes the normal processed signal against the next present processed signal. 
       FIG. 34  is a representation of two processed signals of the output of a sensor  42  that was filtered by four Band-pass filters, BPF 1 , BPF 2 , BPF 3 , and BPF 4 . The processed signals are represented within frequency bandwidths a 1 , a 2 , a 3 , and a 4  that correspond to the bandwidths of the four Band-pass filters, BPF 1 , BPF 2 , BPF 3 , and BPF 4 .  FIG. 34  illustrates a graph of voltage amplitude versus frequency of the processed signal. 
     The voltage amplitudes of the normal and present processed signals are represented by solid vertical lines. The normal processed signal is in the solid lines while the present processed signal is in the dashed lines represents a present/current processed signal, as described above. There is a baseline threshold value  60  that is used to allow for a predictable amount of noise to be disregarded, similar to the baseline threshold  60  of  FIG. 33 . The difference between the two iterations are calculated and shown as δ 1 , δ 2 , and δ 3  in  FIG. 34 . There are various threshold values that are compared to the various δ values to determine the damage of the surgical instrument  10 , indicating an acceptable δ, a marginal δ, or a critical δ that would indicate the need to replace or repair the instrument  10 . 
     In at least one instance, one or more voltage amplitudes are compared to corresponding voltage amplitudes in a previously recorded noise pattern to assess any damage of the surgical instrument  10 . The difference between a present voltage amplitude and a previously-stored voltage amplitude can be compared against one or more predetermined thresholds, which can be stored in the memory  38 , to select an output of an acceptable, marginal, or critical status. 
     In at least one instance, the differences between the present voltage amplitudes and the previously stored voltage amplitudes are summed and compared to one or more predetermined thresholds stored in the memory  38 , for example, to select an output of an acceptable, marginal, or critical status. Magnitude of deviance could be compared range to range to indicate shear change in a local event. 
     In various instances, one or more algorisms, which may be stored in the memory  38 , can be employed by the processor  36  to determine a damage/function status of the surgical instrument  10  based on the processed signal of the output of the sensor  42 . Different noise signals that are recorded by the sensor  42  can be construed to represent different damage/function statuses of the surgical instrument  10 . During normal operation, a normal or expected noise signal is recorded by the sensor  42 . When an abnormal noise signal is recorded by the sensor  42 , it can be further evaluated by the processor  36 , using one or more of the algorisms stored in the memory  38 , to determine a damage/function status of the surgical instrument  10 . The abnormal signal may comprise unique characteristics that can be used to assess the nature of the damage to the surgical instrument  10 . For example, the unique characteristics of the abnormal signal may be indicative of damage to a particular component of the surgical instrument  10 , which can be readily replaced. 
     In certain instances, one or more algorisms are configured to assess normal wear in one or more components of the surgical instrument  10  based on the processed signal of the output of the sensor  42 . Normal wear can be detected by identifying a noise signal indicative of potential debris, for example. When the debris, as measured by its recorded noise signs, reaches or exceeds a predetermined threshold stored in the memory  38 , for example, the processor  36  can be configured to issue an alert that surgical instrument  10  is nearing the end of its life or requires maintenance, for example. 
     Furthermore, one or more algorisms can be configured to determine potential damage to one or more gear mechanisms such as, for example, a planet gear mechanism within the drive mechanism  160  based on the processed signal of the output of a sensor  42 . During normal operation, the planet gear may produce a normal noise signal as recorded by the sensor  42 . When the planet gear is damaged due to a broken tooth, for example, an abnormal noise signal is recorded by the sensor  42 . The abnormal signal may comprise unique characteristics indicative of a damaged planet gear, for example. 
       FIG. 35  is a representation of a processed signal of the output of a sensor  42  that was filtered by four Band-pass filters, BPF 1 , BPF 2 , BPF 3 , and BPF 4 . The processed signal is represented within frequency bandwidths a 1 , a 2 , a 3 , and a 4  that correspond to the bandwidths of the four Band-pass filters, BPF 1 , BPF 2 , BPF 3 , and BPF 4 . Various algorisms, as described above, can be applied to the processed signal of  FIG. 35  to determine a damage/function status of the surgical instrument  10 . 
     Like  FIG. 33 ,  FIG. 35  illustrates a graph of voltage amplitude versus frequency of the processed signal. The voltage amplitudes of the processed signal are represented by solid vertical lines. Within each of the bandwidths a 1 , a z , a 3 , and a 4 , the processed signal is evaluated within an expected range defined by an amplitude threshold and a sub-bandwidth threshold. Expected ranges E 1 , E 2 , E 3 , and E 4  correspond to the bandwidths a 1 , a z , a 3 , and a 4 , respectively. 
     In the example illustrated in  FIG. 35 , a first event indicative of potential planet damage is observed. The observed first event includes a processed signal that comprises two voltage amplitude readings that are indicative of potential planet damage. The two voltage amplitude readings are a first voltage amplitude reading that exceeds the expected range E 1  at the center frequency of the bandwidth a 1 , and a second voltage amplitude reading at a frequency that falls between but outside the bandwidths a 1  and a 2 . A first algorism may be configured to recognize the observed event as indicative of potential planet damage. The processor  36  may employ the first algorism to conclude that potential planet damage is detected. 
     Also, in the example illustrated in  FIG. 35 , a second event indicative of a unique potential damage in connection with a hub of the surgical instrument  10  is observed. The second event includes a processed signal that comprises a voltage amplitude reading that falls below the expected voltage amplitude threshold at the center frequency of the bandwidth a 2 . In addition, the processed signal comprises voltage amplitude readings Z 1  and Z 2  that exceed the baseline threshold value  60 , and are within the bandwidth a z , but fall outside the sub-bandwidth threshold of the Expected range E 2 . A second algorism may be configured to recognize the observed second event as indicative of a unique potential damage. The processor  36  may employ the second algorism to conclude that potential damage in connection with a hub of the surgical instrument  10  is detected. 
     Also, in the example illustrated in  FIG. 35 , a third event indicative of potential debris indicative of wear associated with one or more components of the surgical instrument  10  is observed. The third event includes a processed signal that comprises a voltage amplitude reading that exceeds the expected voltage amplitude threshold at the center frequency of the bandwidth a 4 . A third algorism may be configured to recognize the observed third event as indicative of potential debris. The processor  36  may employ the third algorism to evaluate the severity of the potential debris based on the difference between the observed voltage amplitude and the expected voltage amplitude threshold, for example. 
     While various details have been set forth in the foregoing description, it will be appreciated that the various aspects of the mechanisms for compensating for drivetrain failure in powered surgical instruments may be practiced without these specific details. For example, for conciseness and clarity selected aspects have been shown in block diagram form rather than in detail. Some portions of the detailed descriptions provided herein may be presented in terms of instructions that operate on data that is stored in a computer memory. Such descriptions and representations are used by those skilled in the art to describe and convey the substance of their work to others skilled in the art. In general, an algorithm refers to a self-consistent sequence of steps leading to a desired result, where a “step” refers to a manipulation of physical quantities which may, though need not necessarily, take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It is common usage to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like. These and similar terms may be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. 
     Unless specifically stated otherwise as apparent from the foregoing discussion, it is appreciated that, throughout the foregoing description, discussions using terms such as “processing” or “computing” or “calculating” or “determining” or “displaying” or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system&#39;s registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices. 
     It is worthy to note that any reference to “one aspect” or “an aspect,” means that a particular feature, structure, or characteristic described in connection with the aspect is included in at least one aspect. Thus, appearances of the phrases “in one aspect” or “in an aspect” in various places throughout the specification are not necessarily all referring to the same aspect. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more aspects. 
     Although various aspects have been described herein, many modifications, variations, substitutions, changes, and equivalents to those aspects may be implemented and will occur to those skilled in the art. Also, where materials are disclosed for certain components, other materials may be used. It is therefore to be understood that the foregoing description and the appended claims are intended to cover all such modifications and variations as falling within the scope of the disclosed aspects. The following claims are intended to cover all such modification and variations. 
     Some or all of the aspects described herein may generally comprise technologies for mechanisms for compensating for drivetrain failure in powered surgical instruments, or otherwise according to technologies described herein. In a general sense, those skilled in the art will recognize that the various aspects described herein which can be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or any combination thereof can be viewed as being composed of various types of “electrical circuitry.” Consequently, as used herein “electrical circuitry” includes, but is not limited to, electrical circuitry having at least one discrete electrical circuit, electrical circuitry having at least one integrated circuit, electrical circuitry having at least one application specific integrated circuit, electrical circuitry forming a general purpose computing device configured by a computer program (e.g., a general purpose computer configured by a computer program which at least partially carries out processes and/or devices described herein, or a microprocessor configured by a computer program which at least partially carries out processes and/or devices described herein), electrical circuitry forming a memory device (e.g., forms of random access memory), and/or electrical circuitry forming a communications device (e.g., a modem, communications switch, or optical-electrical equipment). Those having skill in the art will recognize that the subject matter described herein may be implemented in an analog or digital fashion or some combination thereof. 
     The foregoing detailed description has set forth various aspects of the devices and/or processes via the use of block diagrams, flowcharts, and/or examples. Insofar as such block diagrams, flowcharts, and/or examples contain one or more functions and/or operations, it will be understood by those within the art that each function and/or operation within such block diagrams, flowcharts, or examples can be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or virtually any combination thereof. In one aspect, several 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), or other integrated formats. Those skilled in the art will recognize, however, that some aspects of the aspects disclosed herein, in whole or in part, can be equivalently implemented in integrated circuits, 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 that designing the circuitry and/or writing the code for the software and or firmware would be well within the skill of one of skill in the art in light of this disclosure. In addition, those skilled in the art will appreciate that the mechanisms of the subject matter described 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 medium used to actually carry out the distribution. Examples of a signal bearing medium include, but are not limited to, the following: a recordable type medium such as a floppy disk, a hard disk drive, a Compact Disc (CD), a Digital Video Disk (DVD), a digital tape, a computer memory, etc.; and a transmission type medium such as a digital and/or an 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.), etc.). 
     All of the above-mentioned U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications, non-patent publications referred to in this specification and/or listed in any Application Data Sheet, or any other disclosure material are incorporated herein by reference, to the extent not inconsistent herewith. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material. 
     One skilled in the art will recognize that the herein described components (e.g., operations), devices, objects, and the discussion accompanying them are used as examples for the sake of conceptual clarity and that various configuration modifications are contemplated. Consequently, as used herein, the specific exemplars set forth and the accompanying discussion are intended to be representative of their more general classes. In general, use of any specific exemplar is intended to be representative of its class, and the non-inclusion of specific components (e.g., operations), devices, and objects should not be taken limiting. 
     With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations are not expressly set forth herein for sake of clarity. 
     The herein described subject matter sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely exemplary, and that in fact many other architectures may be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being “operably connected,” or “operably coupled,” to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being “operably couplable,” to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components, and/or wirelessly interactable, and/or wirelessly interacting components, and/or logically interacting, and/or logically interactable components. 
     Some aspects may be described using the expression “coupled” and “connected” along with their derivatives. It should be understood that these terms are not intended as synonyms for each other. For example, some aspects may be described using the term “connected” to indicate that two or more elements are in direct physical or electrical contact with each other. In another example, some aspects may be described using the term “coupled” to indicate that two or more elements are in direct physical or electrical contact. The term “coupled,” however, also may mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other. 
     In some instances, one or more components may be referred to herein as “configured to,” “configurable to,” “operable/operative to,” “adapted/adaptable,” “able to,” “conformable/conformed to,” etc. Those skilled in the art will recognize that “configured to” can generally encompass active-state components and/or inactive-state components and/or standby-state components, unless context requires otherwise. 
     While particular aspects of the subject matter described herein have been shown and described, it will be apparent to those skilled in the art that, based upon the teachings herein, changes and modifications may be made without departing from the subject matter described herein and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of the subject matter described herein. It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that when a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to claims containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. 
     In addition, even when a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that typically a disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms unless context dictates otherwise. For example, the phrase “A or B” will be typically understood to include the possibilities of “A” or “B” or “A and B.” 
     With respect to the appended claims, those skilled in the art will appreciate that recited operations therein may generally be performed in any order. Also, although various operational flows are presented in a sequence(s), it should be understood that the various operations may be performed in other orders than those which are illustrated, or may be performed concurrently. Examples of such alternate orderings may include overlapping, interleaved, interrupted, reordered, incremental, preparatory, supplemental, simultaneous, reverse, or other variant orderings, unless context dictates otherwise. Furthermore, terms like “responsive to,” “related to,” or other past-tense adjectives are generally not intended to exclude such variants, unless context dictates otherwise. 
     In certain cases, use of a system or method may occur in a territory even when components are located outside the territory. For example, in a distributed computing context, use of a distributed computing system may occur in a territory even though parts of the system may be located outside of the territory (e.g., relay, server, processor, signal-bearing medium, transmitting computer, receiving computer, etc. located outside the territory). 
     A sale of a system or method may likewise occur in a territory even when components of the system or method are located and/or used outside the territory. Further, implementation of at least part of a system for performing a method in one territory does not preclude use of the system in another territory. 
     Although various aspects have been described herein, many modifications, variations, substitutions, changes, and equivalents to those aspects may be implemented and will occur to those skilled in the art. Also, where materials are disclosed for certain components, other materials may be used. It is therefore to be understood that the foregoing description and the appended claims are intended to cover all such modifications and variations as falling within the scope of the disclosed aspects. The following claims are intended to cover all such modification and variations. 
     In summary, numerous benefits have been described which result from employing the concepts described herein. The foregoing description of the one or more aspects has been presented for purposes of illustration and description. It is not intended to be exhaustive or limiting to the precise form disclosed. Modifications or variations are possible in light of the above teachings. The one or more aspects were chosen and described in order to illustrate principles and practical application to thereby enable one of ordinary skill in the art to utilize the various aspects and with various modifications as are suited to the particular use contemplated. It is intended that the claims submitted herewith define the overall scope. 
     Various aspects of the subject matter described herein are set out in the following numbered clauses: 
     1. A surgical apparatus, comprising an end effector configured to interact with a tissue; and a surgical instrument, comprising at least one drive mechanism operable to effect at least one motion in the end effector; and one or more vibration sensors configured to record vibrations generated by the at least one drive mechanism, wherein the one or more vibration sensors are configured to generate an output signal based on the sensed vibrations, and wherein the output signal is employed to select between an acceptable status, a marginal status, and a critical status of the surgical instrument. 
     2. The surgical apparatus of clause 1, further comprising at least one frequency filter configured to receive the output signal of the one or more vibration sensors, wherein the at least one frequency filter is configured to generate a filtered signal based on the received output signal. 
     3. The surgical apparatus of any one of clauses 1-2, further comprising a memory storing predetermined threshold values associated with the acceptable status, the marginal status, and the critical status; and a processor in communication with the at least one frequency filter. 
     4. The surgical apparatus of any one of clauses 1-3, wherein the memory includes program instructions which, when executed by the processor, cause the processor to generate a processed signal based on the filtered signal. 
     5. The surgical apparatus of any one of clauses 1-4, wherein the memory includes program instructions which, when executed by the processor, cause the processor to employ a fast Fourier transform to develop the processed signal. 
     6. The surgical apparatus of any one of clauses 1-4, wherein the program instructions, when executed by the processor, cause the processor to compare the predetermined threshold values to corresponding values of the processed signal. 
     7. The surgical apparatus of any one of clauses 1-4 or 6, wherein the program instructions, when executed by the processor, cause the processor to detect a critical malfunction of the surgical instrument when the predetermined threshold values associated with the critical status are equal to or less than the corresponding values of the processed signal. 
     8. The surgical apparatus of any one of clauses 1-4, 6 or 7, wherein the program instructions, when executed by the processor, cause the processor to detect an acute malfunction of the surgical instrument when the predetermined threshold values associated with the critical status are greater than the corresponding values of the processed signal, and the predetermined threshold values associated with the marginal status are equal to or less than the corresponding values of the processed signal. 
     9. The surgical apparatus of any one of clauses 1-3, wherein the predetermined threshold values are generated from a test output signal of the one or more vibration sensors. 
     10. The surgical apparatus of any one of clauses 1-3 or 9, wherein the test output signal is based on test vibrations recorded by the one or more vibration sensors during a testing procedure of the surgical instrument. 
     11. The surgical apparatus of any one of clauses 1-3, wherein the predetermined threshold values are generated from a previously processed signal. 
     12. A method for assessing performance of a surgical instrument including one or more drivetrains, the method comprising sensing via one or more vibration sensors vibrations generated during operation of the one or more drivetrains of the surgical instrument; generating an output signal based on the sensed vibrations; filtering the output signal to generate a filtered signal of the sensed vibrations from the one or more drivetrains; processing the filtered signal to generate a processed signal of the sensed vibrations from the one or more drivetrains; and comparing predetermined threshold values for each of an acceptable status, a marginal status, and a critical status of the surgical instrument to corresponding values of the processed signal. 
     13. The method of clause 12, further comprising detecting a critical malfunction of the surgical instrument when the predetermined threshold values associated with the critical status are equal to or less than the corresponding values of the processed signal. 
     14. The method of clause 12, further comprising detect an acute malfunction of the surgical instrument when the predetermined threshold values associated with the critical status are greater than the corresponding values of the processed signal, and the predetermined threshold values associated with the marginal status are equal to or less than the corresponding values of the processed signal. 
     15. The method of any one of clauses 12-13, wherein the predetermined threshold values are generated from a test output signal. 
     16. The method of any one of clauses 12-13, wherein the test output signal is based on vibrations sensed by the one or more vibration sensors during a testing procedure of the surgical instrument. 
     17. The method of clause 12, wherein the predetermined threshold values are generated from a previously processed signal. 
     18. A surgical stapler, comprising a staple cartridge comprising a plurality of staples deployable into tissue; at least one drive mechanism operable to deploy the plurality of staples into the tissue during a firing sequence of the surgical stapler; and one or more vibration sensors configured to record vibrations generated by the at least one drive mechanism, wherein the one or more vibration sensors are configured to generate an output signal based on the sensed vibrations, and wherein the output signal is employed to select between an acceptable status, a marginal status, and a critical status of the at least one drive mechanism. 
     19. The surgical stapler of clause 18, further comprising at least one frequency filter configured to receive the output signal of the one or more vibration sensors, wherein the at least one frequency filter is configured to generate a filtered signal based on the received output signal. 
     20. The surgical stapler of any one of clauses 18-19, further comprising a memory storing predetermined threshold values associated with the acceptable status, the marginal status, and the critical status; and a processor in communication with the at least one frequency filter.