Patent Publication Number: US-2015060141-A1

Title: Downhole motor sensing assembly and method of using same

Description:
BACKGROUND 
     This present disclosure relates generally to techniques for performing wellsite operations. More specifically, the present disclosure relates to techniques, such as drilling motors, for drilling wellbores. 
     Oilfield operations may be performed to locate and gather valuable downhole fluids. Oil rigs are positioned at wellsites, and downhole equipment, such as drilling tools, are deployed into the ground by a drill string to reach subsurface reservoirs. At the surface, an oil rig is provided to deploy stands of pipe into the wellbore to form the drill string. Various surface equipment, such as a top drive, or a Kelly and a rotating table, may be used to apply torque to the stands of pipe, to threadedly connect the stands of pipe together, and to rotate the drill bit. A drill bit is mounted on the lower end of the drill string, and advanced into the earth by the surface equipment to form a wellbore. 
     The drill string may be provided with various downhole components, such as a bottom hole assembly (BHA), drilling motor, measurement while drilling, logging while drilling, telemetry and other downhole tools, to perform various downhole operations. The drilling motor may be provided to drive the drill bit and advance the drill bit into the earth. Examples of drilling motors are provided in U.S. Pat. Nos. 7,419,018, 7,461,706, 6,439,318, 6,431,294, 2007/0181340, and 2011/0031020, the entire contents of which are hereby incorporated by reference herein. 
     SUMMARY 
     In at least one aspect, the disclosure relates to a downhole sensing assembly for sensing motor parameters of a downhole motor positionable in a wellbore penetrating a subterranean formation. The downhole motor has a stator and a rotor rotatable within the stator. The rotor extension is operatively connectable to the rotor and movable therewith. The marker is positionable about the at least one rotor extension. The motor sensor is positionable about the downhole tool and operatively coupled to the at least one marker to detect movement of the at least one marker whereby motor parameters comprising rotational speed of the motor are detectable. 
     At least one of the rotor extension, the marker and the motor sensor are positioned outside of the downhole motor. The marker is integral with the rotor extension. The marker is operatively connectable to the rotor extension. The rotor extension includes a rotor catch. The rotor extension includes a rod threadedly connectable to an end of the rotor. The rotor extension extends from an uphole end of the rotor. The rotor extension extends from the rotor and into a sub adjacent to the motor. The rotor extension includes a handle with a plurality of members extending therefrom. The members are integral with the marker. The marker is integral with the rotor extension. The marker is operatively connectable to the rotor extension. 
     The rotor extension includes an integral or a modular body. The rotor includes an upper portion and a lower portion threadly connectable to the rotor. The marker is positionable about the lower portion. The marker includes a magnet generating a magnetic field detectable by the sensor. The motor sensor includes at least one of a magnetic, electromagnetic, proximity, optical, electro-magnetic, acoustic, fluxgate, magneto-resistive, magnetometer, and Hall Effect sensor. The downhole sensing assembly may also include at least one downhole sensor comprising at least one of a temperature, pressure, vibration, force, and gyroscope sensor. 
     In another aspect, the disclosure relates to a drilling system for drilling a wellbore in a subterranean formation. The drilling system includes a downhole motor positionable in a downhole drilling tool disposable in the wellbore (the downhole motor includes a stator and a rotor), and a downhole sensing assembly. The downhole sensing assembly includes at least one rotor extension operatively connectable to the rotor and movable therewith, at least one marker positionable about the rotor extension, and at least one motor sensor positionable about the downhole tool and operatively coupled to the one marker to detect movement of the marker whereby motor parameters comprising rotational speed of the motor are detectable. 
     The drilling system may also include a surface unit and/or a downhole unit operatively connected to the downhole sensing assembly, telemetry operatively coupling the surface unit and the downhole sensing assembly, and/or a top sub operatively connected to the downhole motor. The rotor extension, the marker and/or the at least one motor sensor may be positioned in the top sub. 
     Finally, in another aspect, the disclosure relates to a method of sensing parameters of a motor of a downhole tool positionable in a wellbore penetrating a subterranean formation. The motor includes a stator and a rotor. The method involves providing the motor with a downhole sensing assembly. The downhole sensing assembly includes at least one rotor extension operatively connectable to the rotor and movable therewith, at least one marker positionable about the rotor extension, and at least one motor sensor positionable about the downhole tool and operatively coupled to the marker to detect movement of the marker. The method further involves detecting the at least one marker with the at least one marker sensor, determining downhole parameters comprising revolutions per minute of the motor based on the detecting, and determining downhole parameters with at least one downhole sensor. The method may also involve selectively adjusting drilling based on at least one of drilling parameters determined from the detecting, downhole parameters determined with the at least one downhole sensor, and known parameters. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the above recited features and advantages of the present disclosure can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof that are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments and are, therefore, not to be considered limiting of its scope. The Figures are not necessarily to scale and certain features, and certain views of the Figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness. 
         FIG. 1  depicts a schematic view, partially in cross-section of a downhole drilling tool deployed into a wellbore, the downhole drilling tool having a drilling motor with a motor sensing assembly. 
         FIG. 2  depicts a cross-sectional view of a portion of the downhole drilling assembly depicting the drilling motor and motor sensing assembly. 
         FIGS. 3A-3C  depict cross-sectional, end and perspective views of a motor sensing assembly. 
         FIGS. 4A-4C  depict cross-sectional, end and perspective views of another motor sensing assembly. 
         FIG. 5  depicts a flow chart of a method of sensing parameters of a motor. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The description that follows includes exemplary apparatus, methods, techniques, and/or instruction sequences that embody techniques of the present subject matter. However, it is understood that the described embodiments may be practiced without these specific details. 
     The present disclosure relates to a motor sensing assembly usable for sensing parameters, such as rotation, of a motor in a downhole tool. The motor sensing assembly may include a rotor extension (e.g., a rotor catch) coupled to a rotor of the motor, a marker positionable about the rotor extension, and a motor sensor coupled to a fixed portion of the downhole tool. The motor sensor may be used to detect changes in magnetic fields caused by rotation of the rotor. The marker may be detectable by the motor sensor to provide, for example, rotational speed of the drilling motor (e.g., revolutions per minute (RPMs) of a stator relative to a rotor of the drilling motor) and/or movement of the rotor (e.g., wobble or whirl). 
     The motor sensing assembly may be positioned outside of the motor and isolated from motion and/or vibration therein. The rotor extension may extend from the rotor and/or motor to facilitate access to the rotor and/or to provide measurements therefrom. The motor sensor may be positioned outside the drilling motor and in a non-rotating portion of the downhole tool to facilitate access to components of the assembly, transfer of measurement, and/or collection of data. The motor sensing assembly may be used for measurement of bit RPM through the motor. The measurements may be used for detection of bit stick/slip, motor performance, and mechanical specific energy (MSE), as well as other info. 
       FIG. 1  depicts an example environment in which a downhole motor with a motor sensing assembly may be used. While a land-based drilling rig with a specific configuration is depicted, the motor sensing assembly may be usable with a variety of land based or offshore applications. In each version, a drilling system  100  includes a rig  101  positionable at a wellsite  102  for performing various wellbore operations, such as drilling. 
       FIG. 1  depicts a schematic view, partially in cross-section, of the wellsite  102 . The drilling system  100  also includes a drill string  103  with a downhole tool (or bottom hole assembly (BHA))  108  and a drill bit  104  at an end thereof. The drill string  103  may include drill pipe, drill collars, coiled tubing or other tubing used in drilling operations. The drill bit  104  is advanced into a subterranean formation  105  to form a wellbore  106 . 
     Various surface (or rig) equipment  107 , such as a Kelly, rotary table, top drive, elevator, etc., may be provided at the rig  101  to rotate the drill bit  104 . A surface unit  112   a  is also provided at the surface to operate the drilling system. Downhole equipment, such as the downhole tool  108 , is deployed from the surface equipment  107  and into the wellbore  106  by the drill string  103  to perform downhole operations. 
     The downhole tool  108  is at a lower end of the drill string  103  and contains various downhole equipment for performing downhole operations. Such equipment may include, for example, measurement while drilling, logging while drilling, telemetry, processors and/or other downhole tools. As shown, the downhole tool  108  includes a downhole unit  112   b  for communication between the downhole tool  108  and the surface unit  112   a . One or more units  112   a,b  may be provided. 
     The downhole tool  108  may also be provided with various devices, such as motor  111  for operating downhole equipment, such as the drill bit  104 . The downhole tool  108  may be provided with one or more motors  111  for rotating the drill bit  104 . As shown, a single motor  111  is positioned between the drill string  103  and the drill bit  104 . The motor  111  may be used to convert hydraulic energy from the mud passing therethrough into rotational energy. The rotational energy may be used to power and/or drive components of the downhole tool  108 . 
     The motor  111  may be any motor with moving parts, such as a moineau motor including a helical rotor  124  rotationally positionable in a helical stator  122  and driven by the flow of mud therethrough. The helical stator  122  may have a number of lobes along an inner surface. The helical rotor  124  may have a number of lobes along a cross-section of an outer surface thereof, with the number of rotor lobes being less than the number of stator lobes. An example of a moineau motor that may be usable is provided in U.S. Pat. No. 7,419,018 previously incorporated by reference herein. The motor  111  may be capable of providing rotation to the bit  104 . 
     The rotor  124  may be attached to a bottom of the motor  111  and allowed to spin relative to a top portion of the motor  111 . The top portion of the motor  111  may be attached to a top sub  126 . The top sub  126  may perform a secondary function of retaining the rotor  124  in case of some type of failure. The motor  111  may be provided with a downhole sensing assembly  119  for detecting downhole parameters, such as rotation of the rotor, as will be described more fully herein. 
     A mud pit  110  may be provided at the surface for passing mud through the drill string  103 , the downhole tool  108  and out the bit  104  as indicated by the arrows. The motor  111  may be activated by fluid flow from the mud pit  110  and through the drill string  103 . Flow of mud from pit  110  may be used to activate the motor  111  during drilling, for example by rotationally driving the motor  111  and/or other downhole components. Pressurized mud flowing through the motor  111  may be used to increase relative RPM from the stator  122  to the rotor  124 . 
       FIG. 2  depicts a portion of the downhole tool  108  of  FIG. 1  with a downhole sensing assembly  219  operatively connected to the motor  111 . As shown in this view, the motor  111  includes a drill collar  220  with a helical stator  222  and helical rotor  224  therein. The top sub  126  includes a drill collar  228  operatively connected to the drill collar  220  of the motor  111  uphole therefrom. 
     The downhole sensing assembly  219  includes a rotor extension  230 , a marker  232 , a motor sensor  234 , and units  112   a,b . The rotor extension  230  is operatively connected to the rotor  224 . As shown, the rotor extension  230  is connected to an uphole end of the rotor  224 , but may be at other locations. As also shown, the rotor extension  230  is positioned in the motor  111 , and extends into the sub  126 . 
     As depicted in  FIG. 2 , the marker  232  and motor sensor  234  are positioned in the sub  126  outside of the motor  111 . The position of the sensing assembly  219  and its components may be selected based on need. For example, the components of the sensing assembly  219  may be positioned outside the motor  111  to isolate such components from movement of the motor  111  and/or fluid turbulence passing therethrough. In at least some cases, components of the sensing assembly  219 , such as the rotor extension  230 , may be positioned outside the motor  111  to prevent interference with the motor  111 . Components of the sensing assembly  219  may also be positioned outside the motor  111  and/or in sub  126  where additional space may be provided for accessing the downhole sensing assembly  219 . 
     The rotor extension  230  may be any device positionable about the rotor  224  and movable therewith for supporting the marker  232 . The rotor extension  230  may be, for example, a rotor catch or handle operatively connected (e.g., threadedly connected) to the rotor  224 . Rotor catches may be used, for example, to access and grip the rotor  224  for retrieval from the motor  111 . The rotor extension  230  may perform other functions associated with the motor  111  and/or downhole tool  108 , such as facilitating removal of the rotor  224 , affecting movement of the rotor  224 , extending the rotor  224  outside of the motor  111 , among others. 
     The marker  232  may be positioned on, in or about the rotor extension  230 . The marker  232  may optionally be a portion of the rotor extension  230  itself and/or be formed integrally therewith. The marker  232  is positioned offset from a central axis A of the rotor  224 . The marker  232  may be identifiable by the motor sensor  234  for measuring various downhole parameters, such as motor parameters of the motor  111 . 
     In an example, the marker  232  may be a magnetic device (such as a magnet, electromagnetic, Hall Effect sensor, etc.) generating a magnetic field M detectable by the motor sensor  234 . As the rotor  224  rotates during operation, the marker  232  moves with the rotor  224  such that the marker  232  is detectable by the motor sensor  234 . The motor sensor  234  may be used, for example, to count the number of times the marker  232  passes by the motor sensor  234 . The frequency with which the magnetic field M changes may be used to calculate, for example, angular rotation rate of the motor  111 . This information may be used, for example, to provide revolutions per minute (RPM) of the rotor  224  and/or torsional vibration of the motor  111 . 
     The motor sensor  234  is positioned along a fixed location along the downhole tool  108 , such as in the drill collar  228  or the stator  222 . The motor sensor  234  may be, for example, removably embedded in the drill collar  228  with a portion extending therefrom. The motor sensor  234  may be positioned for operative coupling with the marker  232 . The motor sensor  234  may also be positioned on a shoulder  236  of the drill collar  228  of the sub  126 . The location of the motor sensor  234  may be in a top, side, and/or bottom portion of the drill collar  228 . The motor sensor  234  may be positioned so that the motor sensor  234  monitors any location of the marker  232 . The motor sensor  234  may also provide other information, such as the location of the motor  111  and/or motor and/or downhole parameters. 
     The motor sensor  234  may be any sensor, such as a proximity sensor with magnetic, electromagnetic, proximity, optical or other capabilities, capable of detecting the marker  224 . The motor sensors  234  may include, for example, a sensor that senses a changing magnetic field, such as an electro-magnetic, acoustic, fluxgate, magneto-resistive, or magnetometer (e.g., Hall Effect) type sensor. For example, the sensor may be a magnetometer (scalar or vector) that may be used to measure a change in magnetic field strength. The motor sensor  234  may also be a distance sensor, such as electro-magnetic or acoustic sensor, that is designed to measure the distance or stand-off of the marker  232  from the motor sensor  234 . 
     Additional sensors, such as downhole sensors S 1  and S 2  may be provided to measure other downhole parameters, such as temperature, pressure, vibration, forces (e.g., torque, bending force, weight on bit), motor dynamics, and other measurements. As shown, downhole sensor S 1  is positioned in the rotor and downhole sensor S 2  is positioned in the rotor extension  230 , and be positioned in any location about motor  111  and/or downhole tool  108 . 
     Measurements made by the motor sensor  234  and the downhole sensors S 1  and S 2  may be analyzed to understand performance and operation of the motor  111  and associated equipment. In an example, the downhole sensors S 1  and/or S 2  may be a gyroscope to provide an ‘earth reference’ and/or position in 3D space. The earth reference may be associated with the RPMs of the motor sensor  234 . The earth reference and RPMs may be analyzed to determine, for example, motor stalling, string driven stick slip dynamics, mechanical specific energy (MSE), among others. The earth reference may also be used to differentiate motor stalling and string driven stick slip dynamics. 
     The motor sensor  234  and downhole sensors S 1  and S 2  may be operatively connected to the surface unit  112   a  and/or a downhole unit  112   b  as schematically depicted. The motor sensing assembly  219  may be wired or wireless coupled to the surface and downhole units  112   a,b  for interaction therewith. Data and/or other signals may be passed between the motor sensor  234  and the surface and/or downhole units  112   a,b . The motor sensor  234  may be used, for example, to count revolutions of the rotor  224  as the marker  232  moves relative to the motor sensor  234 . The revolutions counted may be passed to the surface and/or downhole units  112   a,b . The data may be collected and/or analyzed to provide motor parameters, such as RPM, speed of rotation, vibration, pressure, etc. 
     Based on the data received, various equipment at the wellsite may be selectively activated. For example, based on the RPMs detected by the motor sensors  234 , the mud flow through the downhole tool, torque applied at the rig, and/or other operating parameters may be selectively adjusted. Optimum operational (e.g., drilling) and/or operational parameters may be determined and/or selected based on the measurements taken using the sensing assembly  219 . 
     The surface and/or downhole units  112   a,b  may be provided with, for example, a processor (e.g., central processing unit (CPU)), filters, memory, and/or other devices for communicating, collecting, processing, analyzing and/or otherwise using the data collected by one or more sensors. Other communication and/or processing devices, such as a telemetry device (e.g., wired-drill pipe, mud pulse, electro-magnetic, acoustic, and/or inductive coupling), transceivers, and antennas may also be coupled to the motor sensor  234 . For example, the drill collars may be wired for wired telemetry through the drill string such that data may be passes through the wired telemetry system. 
     The data taken from the various sensors may be filtered with the filter (e.g., a low-pass, high-pass, or bandpass filter). The filtered data may then be acquired by an analog-to-digital converter, frequency-counter, or digital input. The acquired data may then be passed to the CPU (e.g., a microcontroller or other processor). The CPU may use the acquired data to determine an increase in RPM from the top sub  126  of the motor  111  to the rotor  224  of the motor  111 . An increase in rotation rate may be saved to internal or external memory. The increase in rotation rate may be passed to the surface using telemetry. 
     The increase in rotation rate may also be combined with additional RPM measurements taken at or above the top sub  126  of the motor  111 . Adding these measurements together may result in the total RPM of the rotor  224  of the motor  111 . Measured RPM of the motor  111  may be combined with other measurements for comparison and/or evaluation. Other measurements may be used for further analysis. For example, RPM may also be determined at the drill bit (e.g.,  104  of  FIG. 1 ) by measuring RPM and recording the data to memory for comparison and/or analysis with the RPM measurements of the rotor extension  230 . In another example, bit RPM through the motor, MSE, bit stick/slip, and motor performance may be determined. 
     Based on the data received from the sensors and/or other sources, the units  112   a, b  may also be capable of sending signals to operate, activate, adjust, or otherwise control operation of the wellsite. The motor  111  and/or downhole tool  108  (as well as other wellsite components) may be selectively activated based on control signals received from the units  112   a,b.    
     As demonstrated by  FIGS. 3A-4C , the rotor extension  230  may take various forms, such as a unitary or modular configuration shaped as desired to achieve the desired function. The rotor extension  230  may be removable and/or replaceable so that various rotor extensions  230  may be tailored for use with specific applications. 
       FIGS. 3A-3C  depict various views of an example downhole sensing assembly  319  usable with the downhole tool  108  of  FIG. 2 .  FIG. 3A  shows the downhole sensing assembly  319  positioned in the downhole tool  108  about the downhole motor  111 .  FIG. 3B  shows a top view of the downhole sensing assembly  319 .  FIG. 3C  shows a perspective view of a rotor extension  330  of the downhole sensing assembly  419 . The rotor extension in this version may be a rotor extension  330  with a unitary body. 
     The rotor extension  330  has a rotor end  340  threadedly connected to an uphole end of a rotor  224 . The rotor extension  330  has an elongate body  342  extending from the rotor end  340  to a flow end  344 . A shoulder portion  343  extends radially about the elongate body  342  adjacent the rotor end  340 . 
     The rotor extension  330  also has a handle  346  at the flow end  344 . The handle  346  may be secured to the body  342  by a bolt  345 . The handle  346  has a generally elliptical shape with radial members  350  extending therefrom and with the flow holes  348  for the passage of fluid therethrough. Flow holes  348  through the handle  346  may allow flow through the motor  111  without much flow restriction. The handle  346  may be in the form of a spinning disk (or hub) with interrupted outer diameter or a series of the members (or splines)  350  extending from the handle  346  either above or below a motor end of the top sub  126 . 
     The members  350  of the rotor extension  330  may be modified to increase resolution and/or accuracy of the measurement. The members  350  may be expanded to reach further out toward the wall of the drill collar  228  of the sub  126 . Additional members  350  may be added to rotor extension  330 . The members  350  may be individual spokes extending from the hub of the handle  346 . In another example, the members  350  may be contoured lobes extending from a central portion of the handle  346 . 
     Portions of the rotor extension  330 , such as members  350 , may be used as a marker  332  with or without additional markers  232 . In this version, the members  350  may act as the marker  332  detectable by the motor sensor  234 . The members  350  may be made of a metal (e.g., steel) that changes a magnetic field of the sensor. The members  350  may also have additional magnetism added thereon, for example, in a form of a magnet. The additional magnetism may be specifically polarized to allow for a north and/or south pole at various specific members  350  in various orders to allow for rotation direction determination. A separate marker (e.g.,  232  of  FIG. 2 ) may optionally be provided with or without the member  350  as the marker  332 . 
     The members  350  and/or markers  332 ,  232  may be positioned above, below, or through a motor end of the top sub  126 . The motor sensor  234  may be positioned facing uphole, downhole, or perpendicular to the centerline A of the rotor  224  with these members  350  extending off the handle  346 . The spinning handle  346  with members  350 /markers  332  may take the place of the extensions or interrupted geometry of the handle  346 . Various embodiments of members  350 , markers  332 , or other interrupted geometry are possible. 
     The motor sensor  234  may be capable of detecting the members  350  and/or marker  232  as they pass adjacent the motor sensor  234  as shown in  FIG. 3B . The members  350  may be counted to determine rotation of the handle  346 , and thereby the RPMs of the rotor  224  relative to the stator  222 . Motor sensor  234  and units  112   a,b  may be provided in the sub  126  as previously described. 
     The motor sensor  234  may be positioned and adjusted to provide a desired standoff between the marker  332  and the motor sensor  234 . The motor sensor  234  may be positioned in the sub  126  and view the members  350  of the handle  346  as they pass by the motor sensor  234 . 
       FIGS. 4A-4C  depict various views of an example downhole sensing assembly  419  usable with the downhole tool  108  of  FIG. 2 .  FIG. 4A  shows the downhole sensing assembly  419  positioned in the downhole tool  108  about the downhole motor  111  ( FIG. 1 ).  FIG. 4B  shows a top view of the downhole sensing assembly  419 .  FIG. 4C  shows a perspective view of a rotor extension  430  of the downhole sensing assembly  419 . The rotor extension  430  may be a rotor catch with a modular body. 
     As shown in  FIG. 4A , the rotor extension  430  has a rotor end  440  threadedly connected to an uphole end of a rotor  224 . As shown in  FIGS. 4A and 4B , the rotor extension  430  has a lower body portion  443  and an upper elongate body portion  445  extending from the rotor end  440  to a flow end  444 . The lower body portion  443  has a flanged end  447  extending radially therefrom. 
     The upper body portion  445  has a threaded connection end  449  threadedly connected to the flanged end  447 . The upper body portion  445  also has an elongate body  451  extending from the connection end  449  to the flow end  444 , and a handle  456  at the flow end  444 . The handle  456  may be secured to the body  451  by a bolt  445 . 
     As shown in the top view of  FIG. 4B , the flanged end  447  has a generally elliptical shape with radial members  450  extending therefrom. In this version, the flanged end  447  acts as a marker  432 . The members  450  and/or marker  432  may be similar to the members  350  and/or marker  332  of  FIGS. 3A-3C . Additional markers  232  may also be provided. 
     The motor sensor  234  is positioned in the drill collar  228  adjacent the flanged end  447 . The motor sensor  234  is capable of detecting the members  450  as they pass adjacent the motor sensor  234  as shown in  FIG. 4B . The members  450  may be counted to determine rotation of the handle  456 , and thereby the RPMs of the rotor  224  in the stator  222 . Motor sensor  234  and units  112   a,b  may be provided in the sub  126  as described herein. 
       FIG. 5  is a flow chart depicting a method of sensing parameters of a motor. The motor may be the motor  111  of a downhole tool  108  and having a rotor and stator as provided herein. The method involves  560 —providing the motor with a downhole sensing assembly. The downhole sensing assembly includes at least one rotor extension operatively connectable to the rotor and movable therewith, at least one marker positionable about the rotor extension, and at least one marker sensor positionable about the downhole tool and operatively coupled to the marker. The method also involves  562 —detecting the marker(s) with the marker sensor (s). 
     The method may also involve  564 —determining downhole parameters (e.g., revolutions per minute) of the motor based on the detecting,  566 —determining downhole parameters with at least one downhole sensor, and/or  568 —selectively adjusting drilling based on drilling parameters determined from the detecting, downhole parameters determined with downhole sensor, and/or other known parameters. The method may be performed in any order, and repeated as desired. 
     It will be appreciated by those skilled in the art that the techniques disclosed herein can be implemented for automated/autonomous applications via software configured with algorithms to perform the desired functions. These aspects can be implemented by programming one or more suitable general-purpose computers having appropriate hardware. The programming may be accomplished through the use of one or more program storage devices readable by the processor(s) and encoding one or more programs of instructions executable by the computer for performing the operations described herein. The program storage device may take the form of, e.g., one or more floppy disks; a CD ROM or other optical disk; a read-only memory chip (ROM); and other forms of the kind well known in the art or subsequently developed. The program of instructions may be “object code,” i.e., in binary form that is executable more-or-less directly by the computer; in “source code” that requires compilation or interpretation before execution; or in some intermediate form such as partially compiled code. The precise forms of the program storage device and of the encoding of instructions are immaterial here. Aspects of the invention may also be configured to perform the described functions (via appropriate hardware/software) solely on site and/or remotely controlled via an extended communication (e.g., wireless, internet, satellite, etc.) network. 
     While the embodiments are described with reference to various implementations and exploitations, it will be understood that these embodiments are illustrative and that the scope of the inventive subject matter is not limited to them. Many variations, modifications, additions and improvements are possible. For example, one or more motor sensing assemblies, motor sensors, markers, members, and/or other features provided herein may be utilized about the motor and/or downhole tool. 
     Plural instances may be provided for components, operations or structures described herein as a single instance. In general, structures and functionality presented as separate components in the exemplary configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the inventive subject matter.