Drill bit assembly imaging systems and methods

Drill bit assembly imaging systems and methods are disclosed herein. An example method disclosed herein includes directing light conveying an image of a target through a portion of a drill bit assembly and capturing the image via an image sensor disposed inside the drill bit assembly. The example method also include determining drilling information based on the image via an image processor disposed inside the drill bit assembly.

FIELD OF THE DISCLOSURE

This disclosure relates generally to drilling applications and, more particularly, to drill bit assembly imaging systems and methods.

BACKGROUND

A downhole drilling tool is often used to drill boreholes to locate and/or produce hydrocarbons. During drilling, information related to a subterranean formation and/or fluids produced via the subterranean formation may assist an operator of the downhole drilling tool. For example, the operator may adjust a trajectory and/or a speed of a drill bit of the downhole drilling tool based on a geological property of the subterranean formation.

SUMMARY

An example apparatus disclosed herein includes a drill bit assembly. The example apparatus also includes an image sensor and an image conduit disposed in the drill bit assembly. The image conduit is to direct light conveying an image to the image sensor. The example apparatus further includes an image processor disposed in the drill bit assembly. The image processor is to process the image to determine information related to a target in the image.

An example method disclosed herein includes directing an image of a target through a portion of a drill bit assembly and capturing the image via an image sensor disposed inside the drill bit assembly. The example method also include determining drilling information based on the image via an image processor disposed inside the drill bit assembly.

Another example apparatus disclosed herein includes a drill bit assembly operatively coupled to a downhole tool. The drill bit assembly includes an image conduit, an image sensor and an image processor. The image sensor is to capture an image of a target via the image conduit, and the image processor is to determine target information based on the image.

DETAILED DESCRIPTION

Drill bit assembly imaging systems and methods are disclosed herein. An example drill bit assembly includes a drill bit and an extension. The extension operatively couples the drill bit to a downhole tool. An example imaging system disclosed herein is disposed in the example drill bit assembly to capture images of targets inside and/or outside the drill bit assembly and to process the images downhole in the drill bit assembly during drilling. For example, the imaging system may determine target information. Target information is information related to one or more targets in one or more of the images. In some examples, the target information includes a size, a trajectory, a color, a texture, a shape, and/or any other information related to the target(s). In some examples, based on the target information, the imaging system determines drilling information. Drilling information is information related to a drilling operation. Drilling information may include, for example, a state and/or condition of a component of the drill bit assembly, penetration of a gas zone by the drill bit, a change in a geological property of a subterranean formation through which the drill bit assembly is drilling, and/or any other information related to the drilling operation. By processing the images downhole, the target information and/or the drilling information may be communicated uphole to a receiver in real time via a low bandwidth, wireless telemetry link.

The example imaging system may include an example image conduit in optical communication with an example image sensor. In some examples, the image sensor captures images at a high frame rate such as, for example, a frame rate of about 1000 frames per second. The example imaging system may also include an example image processor disposed in the drill bit assembly to process the images captured by the image sensor. In some examples, the image processor combines a plurality of images captured by the image sensor to generate one or more processed images having less or substantially no blur relative to the images captured by the image sensor. Based on the processed image(s), the image processor may determine the target information and/or the drilling information.

FIG. 1illustrates an example wellsite system in which the examples disclosed herein can be employed. The wellsite can be onshore or offshore. In this example system, a borehole11is formed in subsurface formations by rotary drilling in any appropriate manner. Examples can also use directional drilling, as will be described hereinafter.

A drill string12is suspended within the borehole11and has a bottom hole assembly100which includes a drill bit105at its lower end. The surface system includes platform and derrick assembly10positioned over the borehole or wellbore11, the assembly10including a rotary table16, a kelly17, a hook18and a rotary swivel19. The drill string12is rotated by the rotary table16, energized by means not shown, which engages the kelly17at the upper end of the drill string12. The drill string12is suspended from the hook18, attached to a traveling block (also not shown), through the kelly17and the rotary swivel19, which permits rotation of the drill string12relative to the hook18. In some examples, a top drive system could be used.

In the illustrated example, the surface system further includes drilling fluid or mud26stored in a pit27formed at the well site. A pump29delivers the drilling fluid26to the interior of the drill string12via a port in the swivel19, causing the drilling fluid26to flow downwardly through the drill string12as indicated by the directional arrow8. The drilling fluid26exits the drill string12via ports in the drill bit105, and then circulates upwardly through the annulus region between the outside of the drill string12and the wall of the borehole11, as indicated by the directional arrows9. In this manner, the drilling fluid26lubricates the drill bit105and carries formation cuttings up to the surface as it is returned to the pit27for recirculation.

The bottom hole assembly100of the illustrated example includes a logging-while-drilling (LWD) module120, one or more measuring-while-drilling (MWD) modules130, a roto-steerable system and a motor, and the drill bit105.

The example LWD module120is housed in a special type of drill collar and can contain one or a plurality of types of logging tools. It will also be understood that more than one LWD and/or MWD module can be employed, for example, as represented at120A. References throughout to a module at the position of120can mean a module at the position of120A as well. The LWD module120includes capabilities for measuring (e.g., information acquiring devices), processing, and storing information (e.g., an information storage device such as, for example, nonvolatile memory), as well as for communicating with the surface equipment such as for example, a logging and control unit160.

The example MWD module130is also housed in a special type of drill collar and can contain one or more devices for measuring characteristics of the drill string12and the drill bit105. The MWD tool further includes an apparatus (not shown) for generating electrical power to the downhole system. This may include a mud turbine generator powered by the flow of the drilling fluid26and/or other power and/or battery systems. In some examples, the MWD module includes one or more of the following types of measuring devices: a weight-on-bit measuring device, a torque measuring device, a vibration measuring device, a shock measuring device, a stick slip measuring device, a direction measuring device, and an inclination measuring device.

FIG. 2is a schematic of an example drill bit assembly200disclosed herein, which may be used to implement the example LWD tool120ofFIG. 1. The example drill bit assembly200ofFIG. 2includes a drill bit202and an extension204. In the illustrated example, the extension204operatively couples the drill bit202to a downhole tool206such as, for example, the measuring-while-drilling (MWD) tool130ofFIG. 1. The example drill bit assembly200may be used to drill a borehole and/or penetrate a subterranean formation. For example, a motor (not shown) operatively coupled to the drill bit assembly200may drive the drill bit202via a drive shaft (not shown). In some examples, drilling fluid is flowed into the borehole to lubricate the drill bit202and/or carry formation cuttings, debris, and/or fluid toward a surface of Earth. In some examples, the drilling fluid is flowed through the downhole tool206and exits the drill bit202via ports208,210. In other examples, the drilling fluid is flowed through the downhole tool206and exits the downhole tool206via a drive shaft channel (not shown) disposed uphole of the drill bit assembly200. In other examples, the drilling fluid is flowed into the borehole in other ways. In some examples, the downhole tool206and/or the drill bit assembly202ofFIG. 2is operated in a way described in U.S. Pat. No. 6,057,784, entitled “Apparatus and System for Making At-Bit Measurements While Drilling,” filed Sep. 2, 1997, which is hereby incorporated by reference herein in its entirety.

During drilling, one or more drilling events may occur. For example, the drill bit202may penetrate a gas zone, the drill bit202may penetrate a layer of a subterranean formation, the drill bit202may move past a first portion of a subterranean formation having a first geological property to a second portion of the subterranean formation having a second geological property, a component of the drill bit assembly200may operate (e.g., a valve may open or close, a turbine may rotate, a shaft may rotate, etc.) and/or one or more other drilling events or combinations of events may occur.

The example drill bit assembly200ofFIG. 2includes an example imaging system211to detect and/or monitor drilling events. In the illustrated example, the imaging system211includes an example image conduit212, an example image sensor214, an example image processor216, and an example first transceiver218. The example first transceiver218includes a transmitter and a receiver. In the illustrated example, the image conduit212substantially extends from an end or tip220of the drill bit202through the drill bit202and into the extension204. In other examples, the image conduit212is disposed in and/or extends between other portions of the example drill bit assembly200. Further, other examples include other numbers of image conduits (e.g., 2, 3, 4, etc.). Moreover, while the example image conduit212ofFIG. 2is substantially straight, the drill bit assembly200is implemented in other examples using one or more curved image conduits.

The example image conduit212ofFIG. 2is a fiber optic image conduit. In other examples, other image conduits such as, for example, lenses, filters, mirrors, and/or other image conduits are employed. A first end222of the example image conduit212ofFIG. 2is in optical communication with (e.g., has an optical field-of-view that includes) a target adjacent the tip220of the drill bit202. In the illustrated example, the target may be formation fluid, cuttings, one or more bubbles, debris, a portion of a subterranean formation, and/or any other target. In some examples, an optical window is disposed between the first end222of the image conduit212and the target. In some examples, the optical window is a sapphire window. In some examples, the optical window isolates, insulates and/or protects the image conduit212from drilling fluid, debris, cuttings, formation fluid, downhole conditions (e.g., high temperatures and/or pressures), etc. In some examples, the optical window includes a coating to protect the optical window and/or repel oil, water and/or other fluids and/or debris. In other examples, the first end222of the image conduit212is in contact with the target. For example, the first end222may be in contact with formation fluid flowing in the borehole. In some examples, the first end222includes a coating to protect the first end222and/or repel oil, water, and/or other fluids and/or debris from the first end222.

In the illustrated example, a second end224of the image conduit212is in optical communication with the image sensor214. The example image conduit212conveys or directs light conveying images from the first end222of the image conduit212to the image sensor214via the second end224. The example image sensor214captures the images at a high frame rate. For example, the image sensor214may capture the images at a frame rate of about 1000 frames per second. In other examples, the image sensor214captures the images at other frame rates. In some examples, the image sensor214is a video camera.

In some examples, flushing fluid is flowed through the ports208,210to project the flushing fluid into a field-of-view of the image sensor214. For example, the flushing fluid may be projected into an area of a borehole adjacent the drill bit assembly200such as, for example, at and/or near the first end222of the image conduit212. In some examples, the flushing fluid is a clear or substantially transparent liquid or gel. Thus, by projecting the flushing fluid into the field-of-view of the image sensor214, the field-of-view of the image sensor214is flushed of obstructions between the image sensor214and the target such as, for example, opaque fluids, debris, and/or other obstructions. As a result, the example image sensor214has an unobstructed field-of-view that includes the target. The example flushing fluid may also clean the target and/or the first end222of the image conduit212. In some examples, the flushing fluid is flowed through the ports208,210periodically or momentarily such as, for example, during a time when the image sensor214is capturing images. In some examples, the example drill bit assembly200uses flushing fluid as described in U.S. application Ser. No. 13/439,824, filed on Apr. 4, 2012, which is hereby incorporated by reference herein in its entirety.

During drilling, the drill bit assembly200moves relative to targets captured in the images. For example, if the target is a bubble, the bubble may flow past the first end222of the image conduit212and/or the drill bit assembly200may be rotating and/or vibrating as the images are captured. The example image processor216processes the images to increase a signal-to-noise ratio of the image sensor214and/or reduce, and/or minimize an effect of motion parallax such as blurring of the images. In the illustrated example, the image processor216combines images to generate a processed image having less or substantially no blur relative to the images captured by the image sensor214. In some examples, the image processor216performs motion and/or depth estimation of the target to generate the processed image. An example image processing technique which may be implemented by the example image processor216ofFIG. 2is described in Komuro et al.,High-S/N Imaging of a Moving Object using a High-frame-rate Camera,2008 IEEE International Conference on Image Processing (ICIP 2008) (San Diego, Oct. 13, 2008), pp. 517-520, which is hereby incorporated by reference herein in its entirety.

For example, noise of the image sensor214may include fixed-pattern noise, random noise, shot noise and/or quantization noise. Assuming that quantization noise is negligible and/or is included in random noise and/or shot noise, a luminance value L(x, y, t) at pixel (x, y) of the image sensor214in frame t may be presented by Equation 1 below:
L(x,y,t)=aI(x,y,t)Tc+
nf(x,y)+nr(x,y,t),  (1)
In equation 1, I(x, y, t) is a light intensity incident on the pixel (x, y) in frame t, Teis an exposure time, nfis fixed pattern noise and nris random noise in the combined image. If luminance does not vary after movement, a relationship can be written as shown in Equation 2:
I(u(x,y,t),v(x,y,t),t)=I(x,y,t0).  (2)
A combined image of F frames {circumflex over (L)}(x, y) is given by Equations 3-4:

If the target is a single plane, movement of the target may be estimated by feature point tracking and/or template matching. If the target is a three dimensional object, a motion map and a depth map may be determined substantially simultaneously. If initial values of the depth map are given, iteration processing may be used to estimate the motion and the depth map of the target alternately via estimation by template matching. In some examples, estimation of motion p(t) of the target and the depth map Z(x, y) is determined in terms of an optimization problem that minimizes the following equation:

⁢J=∑t⁢∑x,y⁢(1F⁢∑⁢L⁡(u,v,t′)-L⁡(u,v,t))2.(5)
If the target is assumed to be rigid, the motion of the target is expressed by the following parameters, including three rotation angles and three translational distances:

p⁡(t)=(θx⁡(t),θy⁡(t),θz⁡(t),tx⁡(t),ty⁡(t),tz⁡(t)).(6)
If p(t0)=0 in a first frame, a three dimensional position (X, Y, Z) of image coordinates (x, y) satisfies the following equations:
X(x,y)=xZ(x,y)/f(7)
Y(x,y)=yZ(x,y)/f(8)
In Equations 7 and 8, f is a focal length. Using Equations 7 and 8, image coordinates u(x, y, t), v(x, y, t) in frame t corresponding to image coordinates (x, y) in the first frame are determined as follows:

2) Obtain p(t) that minimizes the following equation:

4) Update {circumflex over (L)}(x, y) using the following equation:

5) Iterate 2)-4) of the algorithm flow a plurality of times.

For motion estimation, p(t) that minimizes J in Equation 11 is equal to p(t) that minimizes Equation 13 below because p(t) is involved in a partial sum for the frame t in Equation 11.

Jt=∑x,y⁢(L^⁡(x,y)-L⁡(u,v,t))2.(13)
In some examples, a solution to Equation 13 is determined using an iterative calculation shown in Equations 14-18 below in which a Lucas-Kanade method is applied to a perspective projection model.

For depth estimation, Z(x, y) that minimizes J in Equation 5 is equal to Z(x, y) that minimizes Equation 19 below and can be calculated for each (x, y):

⁢Jx,y=∑⁢(1F⁢∑⁢L⁡(u,v,t′)-L⁡(u,v,t))2(19)
This is a one-dimensional search. By using information of a plurality of frames in this manner, the depth may be estimated. In some examples, Jx,yis smoothed via a Gaussian filter before searching for Z(x, y) that minimizes Jx,y. In some examples, the depth map is smoothed for each iteration.

The example image processor216ofFIG. 2determines target information based on the sensed images and/or the processed image(s). In some examples, the image processor216determines target information such as, for example, object boundary information, a trajectory of the target, a shape of the target, a number of targets in the images and/or the processed image(s), a color of the target, a texture of the target, and/or other target information. In some examples, the image processor216is used to implement image-based downhole fluid analysis such as, for example, the image-based downhole fluid analysis implemented in U.S. Pat. No. 8,483,445, filed on Sep. 26, 2011, which is hereby incorporated by reference herein in its entirety.

In some examples, the image processor216analyzes and/or processes the target information to determine and/or detect a drilling event such as, for example, penetration of a gas zone, penetration of a layer of a subterranean formation, a change in a geological property of a subterranean formation through which the drill bit202is drilling, and/or any other drilling event. In some examples, the image processor216generates drilling information including a determination of the drilling event based on the target information. The example image processor216can, for example, compress, encrypt, modulate and/or filter the target information and/or the drilling information to format the target information and/or the drilling information. In some examples, formatted target information and/or formatted drilling information is communicated from the drill bit assembly200via the first transceiver218to a second transceiver226of the downhole tool206, and the formatted target information and/or the formatted drilling information is reported via a telemetry link228toward a surface of Earth. The example telemetry link228may be a modem or a low bandwidth telemetry link such as, for example, a mud-pulse telemetry link. Because the example image processor216processes the images downhole to determine the target information and/or the drilling information, which can include less data than the original image, the target information and/or the drilling information is communicated uphole to the surface of Earth via the telemetry link228in real-time. As a result, the example imaging system211enables an operator of the example downhole tool206to quickly and timely respond to the event. For example, based on the drilling information, the operator may adjust a speed of rotation of the drill bit202, a trajectory of the drill bit202, etc.

In the illustrated example, the first transceiver218and the second transceiver226enable communication between the example drill bit assembly200and the example downhole tool206. Thus, information may be communicated from the downhole tool206to the drill bit assembly200. In some examples, information from the surface is communicated to the drill bit assembly200in real time via the telemetry link228, the second transceiver226and the first transceiver218.

FIG. 3illustrates the example drill bit assembly200ofFIG. 2having the image conduit212extending from inside the extension204to a side300of the extension204. Thus, the example image conduit212ofFIG. 3may be used to capture images of targets adjacent the extension204such as, for example, a penetrated portion of a subterranean formation, formation fluid, cuttings, drilling fluid and/or any other target.

FIG. 4is a schematic of the example downhole tool206including an example drill bit assembly400having another example imaging system401disclosed herein. The example drill bit assembly400ofFIG. 4includes a drill bit402and an extension404. In the illustrated example, the imaging system401includes a first example image conduit406, a second example image conduit408and a third example image conduit410. Other examples have other numbers of image conduits. In the illustrated example, the first image conduit406extends from the extension404to an end or tip412of the drill bit402. The example second image conduit408is disposed in the extension404and extends to a first side414of the extension404. The example third image conduit410is disposed in the extension404and extends to a second side416of the extension404.

In the illustrated example, each of the first image conduit406, the second image conduit408and the third image conduit410includes an example imaging fiber bundle417and an example illumination fiber bundle418. The example imaging fiber bundles417enable images to be conveyed along lengths of the respective image conduits406,408,410. The example illumination fiber bundles418are disposed adjacent the imaging fiber bundles417. In some examples, the illumination fiber bundles418substantially surround the imaging fiber bundles417. In the illustrated example, the illumination fiber bundles418convey light generated from a light source419to, for example, illuminate areas adjacent the drill bit assembly400.

In the illustrated example, each of the first image conduit406, the second image conduit408and the third image conduit410direct the images to an example hemispherical mirror420disposed in the extension404. The example hemispherical mirror420ofFIG. 4reflects the images to an example image sensor421via a lens422disposed between the hemispherical mirror420and the image sensor421. Thus, in the illustrated example, the example image sensor421captures images of targets disposed in a plurality of positions or areas relative to the drill bit assembly400via the first image conduit406, the second image conduit408and the third image conduit410. In the illustrated example, the image sensor421captures the images at a high frame rate.

The example drill bit assembly400ofFIG. 4includes an example image processor424to process and/or analyze the images captured by the example image sensor421. In some examples, the image processor424processes the images to increase a signal-to-noise ratio of the image sensor421and/or reduce, and/or minimize an effect of motion parallax such as blurring of the images. In the illustrated example, the image processor424combines images of each the targets to generate processed images having less or substantially no blur relative to the images captured by the image sensor421. In some examples, the image processor424performs motion and/or depth estimation of the target to generate the processed image. An example image processing technique which may be implemented by the example image processor424ofFIG. 4is described in Komuro et al.,High-S/N Imaging of a Moving Object using a High-frame-rate Camera,2008 IEEE International Conference on Image Processing (ICIP 2008) (San Diego, Oct. 13, 2008), pp. 517-520, which is discussed above.

The example image processor424ofFIG. 4determines target information based on the sensed images and/or the processed image(s). In some examples, the image processor424determines object boundary information, trajectories of the targets, target shapes, numbers of targets, colors of the targets, textures of the targets, and/or other target information. In some examples, the image processor424determines target information by implementing image-based downhole fluid analysis such as, for example, the image-based downhole fluid analysis described in U.S. Pat. No. 8,483,445, filed on Sep. 26, 2011. For example, based on the images, the image processor424may characterize and/or identify formation fluids, quantify an amount of oil and/or water included in the formation fluids, and/or conduct other types of downhole fluid analyses. Other downhole fluid analysis techniques which may be implemented using the example image processor424are described in U.S. Publication No. 2007/0035736, filed on Aug. 15, 2005; U.S. Pat. No. 5,663,559, filed Jun. 7, 1995; U.S. Pat. No. 7,675,029, filed Aug. 26, 2004; and U.S. Pat. No. 5,410,391, filed Jun. 15, 1990. U.S. Publication No. 2007/0035736, U.S. Pat. No. 5,663,559, U.S. Pat. No. 7,675,029, and U.S. Pat. No. 5,410,391 are hereby incorporated herein by reference in their entireties.

In some examples, the image processor424analyzes and/or processes the target information to determine and/or detect a drilling event such as, for example, penetration of a gas zone, penetration of a layer of a subterranean formation, a change in a geological property of a subterranean formation through which the drill bit402is drilling, and/or any other drilling event. In some examples, if a drilling event is detected, the image processor424generates drilling information based on the target information. In some examples, the example image processor424formats the target information and/or the drilling information by compressing, encrypting, modulating and/or filtering the target information and/or the drilling information.

The target information and/or the drilling information is communicated from the example drill bit assembly400via a wireless transmitter426to the second transceiver226of the example downhole tool206. In some examples, the wireless transmitter426is included in a transceiver disposed on the drill bit assembly400. In the illustrated example, the target information and/or the drilling information is communicated from the downhole tool206toward a surface of earth via the telemetry link228. In some examples, the telemetry link228implements a low bandwidth telemetry link such as, for example, a mud-pulse telemetry link. By processing the target information and/or the drilling information downhole in the example drill bit assembly400, the target information may be communicated from example drill bit assembly400to the surface of Earth in real-time. As a result, an operator of the example drill bit assembly400may respond to the drilling information and/or the target information by, for example, by adjusting an operating parameter of the drill bit assembly400such as, for example, a speed of rotation of the drill bit402, an angle of trajectory of the drill bit402, etc.

In some examples, flushing fluid is flowed through ports428,430to project the flushing fluid into a field-of-view of the image sensor421. In some examples, the flushing fluid flushes away obstructions and/or cleans the targets, the first image conduit406, the second image conduit408and/or the third image conduit410. In some examples, the example drill bit assembly400implements techniques involving flushing fluid that are described in U.S. application Ser. No. 13/439,824, filed on Apr. 4, 2012.

FIG. 5is a schematic of the example downhole tool206having another example drill bit assembly500disclosed herein. In the illustrated example, the drill bit assembly500includes a drill bit502and an extension504. The example drill bit assembly500ofFIG. 5includes an example imaging system506that is used to detect and/or determine drilling information such as, for example, movement, a position and/or a condition of one or more components of the example drill bit assembly500. In the illustrated example, the imaging system506is used to monitor a valve508operatively coupled to a shaft510disposed in the example extension504. For example, the imaging system506may be used to detect a position of the valve508, a state of wear and/or a condition of one or more components of the valve, and/or other information. Although the following examples are described in conjunction with the example valve508ofFIG. 5, in other examples, the imaging system506is used to detect and/or monitor other components of the drill bit assembly500.

The example imaging system506includes an image conduit512disposed between the valve508and an example image sensor513. In the illustrated example, the image conduit512includes an example imaging fiber bundle514and an example illumination fiber bundle516. The example illumination fiber bundle516is illuminated via an example light source518to illuminate a field of view including at least a portion of the example valve508. In the illustrated example, the imaging fiber bundle514directs light conveyed images of the example valve508to the image sensor513via a lens520.

The example imaging system506ofFIG. 5includes an example image processor522to process and/or analyze the images captured by the example image sensor513. In some examples, the image processor522processes the images to increase a signal-to-noise ratio of the image sensor513and/or reduce and/or minimize an effect of motion parallax such as blurring of the images. For example, rotation of the valve508may cause an image of the valve508captured by the image sensor513to be blurred. In the illustrated example, the image processor522combines images to generate a processed image having less or substantially no blur relative to the images captured by the image sensor513. In some examples, the image processor522performs motion and/or depth estimation of a target in the image (e.g., a portion of the valve508) to generate the processed image. An example image processing technique which may be implemented by the example image processor522ofFIG. 5is described in Komuro et al.,High-S/N Imaging of a Moving Object using a High-frame-rate Camera,2008 IEEE International Conference on Image Processing (ICIP 2008) (San Diego, Oct. 13, 2008), pp. 517-520, which is discussed above.

The example image processor522ofFIG. 5determines target information based on the sensed images and/or the processed image(s). For example, the image processor522determines object boundary information, a shape of a target, a color of the target, a texture of the target, and/or other target information. In some examples, based on the target information, the image processor522determines drilling information such as, for example, movement of the valve508, a position of the valve508, a state of the valve (e.g., open or closed, operating, etc.), a condition of one or more components of the valve508, and/or other drilling information. In some examples, the example image processor522formats the target information and/or the drilling information by compressing, encrypting, modulating and/or filtering the target information and/or the drilling information.

The target information and/or the drilling information is communicated to the example downhole tool206via a wireless transmitter524. The target information and/or the drilling information is received by the second transceiver226and communicated to a surface of Earth via the telemetry link228. In some examples, the telemetry link228is a low bandwidth telemetry link such as, for example, a mud-pulse telemetry link. By processing the target information and/or the drilling information downhole in the example drill bit assembly500, the target information and/or the drilling information may be communicated to the surface of Earth in real-time. As a result, an operator of the example drill bit assembly500may determine if the example valve508is operating properly, if a component of the valve508is worn, etc.

FIG. 6is a schematic of an example image conduit600disclosed herein, which may be used to implement the example image conduit212ofFIGS. 2-3, the example first image conduit406ofFIG. 4, the example second image conduit408ofFIG. 4, the example third image conduit410ofFIG. 4, and/or the example image conduit512ofFIG. 5. In the illustrated example, the image conduit600includes an example imaging fiber bundle602having a plurality of imaging fibers604. The example imaging fibers604convey images from a first end606to a second end608of the example image conduit600.

The example image conduit600also includes an example illumination fiber bundle610having a plurality of illumination fibers612. Light is conveyed to a field-of-view via the example illumination fibers612. In the illustrated example, the illumination fibers612are disposed adjacent the imaging fiber bundle602. In some examples, the illumination fibers612substantially surround the imaging fiber bundle602. In some examples, the image conduit600is flexible and may be bent or curved during operation. In other examples, the image conduit600is rigid and/or substantially straight. Other example image conduits which may be used to implement the examples disclosed herein are described in U.S. patent application Ser. No. 13/654,408, filed on Oct. 17, 2012, which is hereby incorporated by reference herein in its entirety.

While example manners of implementing the example imaging system211, the example imaging system401, and the example imaging system506are illustrated inFIGS. 2-5, one or more of the elements, processes and/or devices illustrated inFIGS. 2-5may be combined, divided, re-arranged, omitted, and/or implemented in any other way. Further, the example image sensor214, the example image processor216, the example first transceiver218, the example second transceiver226, the example telemetry link228, the example light source419, the example image sensor421, the example image processor424, the example transmitter426, the example image sensor513, the example light source518, the example image processor522, the example transmitter524and/or, more generally, the example imaging system211ofFIGS. 2 and 3, the example imaging system401ofFIG. 4, and/or the example imaging system506ofFIG. 5may be implemented by hardware, software, firmware and/or any combination of hardware, software and/or firmware. Thus, for example, any of the example image sensor214, the example image processor216, the example first transceiver218, the example second transceiver226, the example telemetry link228, the example light source419, the example image sensor421, the example image processor424, the example transmitter426, the example image sensor513, the example light source518, the example image processor522, the example transmitter524and/or, more generally, the example imaging system211ofFIGS. 2 and 3, the example imaging system401ofFIG. 4, and/or the example imaging system506ofFIG. 5could be implemented by one or more analog or digital circuit(s), logic circuits, programmable processor(s), application specific integrated circuit(s) (ASIC(s)), programmable logic device(s) (PLD(s)) and/or field programmable logic device(s) (FPLD(s)). When reading any of the apparatus or system claims of this patent to cover a purely software and/or firmware implementation, at least one of the example image sensor214, the example image processor216, the example first transceiver218, the example second transceiver226, the example telemetry link228, the example light source419, the example image sensor421, the example image processor424, the example transmitter426, the example image sensor513, the example light source518, the example image processor522, the example transmitter524and/or, more generally, the example imaging system211ofFIGS. 2 and 3, the example imaging system401ofFIG. 4, and/or the example imaging system506ofFIG. 5is/are hereby expressly defined to include a tangible computer readable storage device or storage disk such as a memory, a digital versatile disk (DVD), a compact disk (CD), a Blu-ray disk, etc. storing the software and/or firmware. Further still, the example imaging system211ofFIGS. 2 and 3, the example imaging system401ofFIG. 4, and/or the example imaging system506ofFIG. 5may include one or more elements, processes and/or devices in addition to, or instead of, those illustrated inFIGS. 2-5, and/or may include more than one of any of the illustrated elements, processes and devices.

A flowchart representative of an example method that may be used to implement the example image sensor214, the example image processor216, the example first transceiver218, the example second transceiver226, the example telemetry link228, the example light source419, the example image sensor421, the example image processor424, the example transmitter426, the example image sensor513, the example light source518, the example image processor522, the example transmitter524, the example imaging system211ofFIGS. 2 and/or 3, the example imaging system401ofFIG. 4, and/or the example imaging system506ofFIG. 5is shown inFIG. 7. The method may be implemented using machine readable instructions that comprise a program for execution by a processor such as the processor812shown in the example processor platform800discussed below in connection withFIG. 8. The program may be embodied in software stored on a tangible computer readable storage medium such as a CD-ROM, a floppy disk, a hard drive, a digital versatile disk (DVD), a Blu-ray disk, or a memory associated with the processor812, but the entire program and/or parts thereof could be executed by a device other than the processor812and/or embodied in firmware or dedicated hardware. Further, although the example program is described with reference to the flowchart illustrated inFIG. 7, many other methods of implementing the example image sensor214, the example image processor216, the example first transceiver218, the example second transceiver226the example telemetry link228, the example light source419, the example image sensor421, the example image processor424, the example transmitter426, the example image sensor513, the example light source518, the example image processor522, the example transmitter524, the example imaging system211ofFIGS. 2 and/or 3, the example imaging system401ofFIG. 4, and/or the example imaging system506ofFIG. 5may be used. For example, the order of execution of the blocks may be changed, and/or some of the blocks described may be changed, omitted, or combined.

The example method700ofFIG. 7begins at block702by directing light conveying an image of a target through a portion of a drill bit assembly. For example, the image conduit212ofFIG. 2may direct light conveying an image of a portion of a subterranean formation through the drill bit202. In some examples, the image conduit512directs light conveying an image of a component of the drill bit assembly500through a portion of the drill bit502and/or the extension504. At block704, the image is captured via an image sensor disposed in the drill bit assembly. For example, the image sensor214may capture the image and/or a plurality of images of the subterranean formation at a high frame rate such as, for example, about 1000 frames per second. At block706, the image is processed via an image processor disposed in the drill bit assembly to generate a processed image. For example, the image processor216may combine the image with a plurality of previously captured images to generate a processed image having less or substantially no blur relative to the images captured by the image sensor214, thereby increasing a signal-to-noise ratio of the image sensor214. In some examples, the image processor216estimates motion and/or depth of the target based on the images captured by the image sensor214to generate the processed image.

At block708, target information is determined based on the processed image. The target information may include, for example, a color of the subterranean formation, a texture of the subterranean formation, and/or other information. In some examples, the target information includes object boundary information, a trajectory of the target, a size of the target, a shape of the target, and/or other target information.

At block710, drilling information is determined based on the target information. In some examples, determining the drilling information includes detecting a drilling event. Example drilling events include penetration of a gas zone by the drill bit, a change in a geological property of a subterranean formation, operation of a component of the drill bit assembly, etc. In some examples, the drilling information includes, a condition of the target (e.g., worn, functioning properly, etc.), a position of the target, a state of the target (e.g., stationary or moving, open or closed, etc.), and/or other drilling information. In some examples, the drilling information includes a characterization of one or more fluids.

At block712, at least one of the target information or the drilling information, or both, is wirelessly communicated uphole toward a surface of Earth. By processing the images downhole, the target information and/or the drilling information may be communicated to the surface of Earth in real time via a low bandwidth transmitter such as, for example, a mud-pulse telemetry link. For example, the first transceiver218may communicate the target information and/or the drilling information to the second transceiver226of the downhole tool206. In some examples, the telemetry link228then communicates the target information and/or the drilling information to the surface of Earth. An operator of the drill bit assembly may then use the target information and/or the drilling information to operate a downhole tool (e.g., the downhole tool206) including the drill bit assembly. The example method700then returns to block702.

FIG. 8is a block diagram of an example processor platform800capable of executing the example method700ofFIG. 7to implement the example imaging system211ofFIGS. 2-3, the example imaging system401ofFIG. 4, and/or the example imaging system501ifFIG. 5. The processor platform800can be, for example, a controller, a special-purpose computing device, a mobile device or any other type of computing device.

The processor platform800of the illustrated example includes a processor812. The processor812of the illustrated example is hardware. For example, the processor812can be implemented by one or more integrated circuits, logic circuits, microprocessors or controllers from any desired family or manufacturer.

The processor platform800of the illustrated example also includes an interface circuit820. The interface circuit820may be implemented by any type of interface standard, such as an Ethernet interface, a universal serial bus (USB), and/or a PCI express interface.

In the illustrated example, one or more input devices822are connected to the interface circuit820. The input device(s)822permit(s) a user to enter data and commands into the processor812. The input device(s) can be implemented by, for example, an audio sensor, a microphone, a camera (still or video), a keyboard, a button, a mouse, a touchscreen, a track-pad, a trackball, isopoint and/or a voice recognition system.

In some examples, one or more output devices824are also connected to the interface circuit820of the illustrated example.

The processor platform800of the illustrated example also includes one or more mass storage devices828for storing software and/or data. Examples of such mass storage devices828include floppy disk drives, hard drive disks, compact disk drives, Blu-ray disk drives, RAID systems, and digital versatile disk (DVD) drives.

The coded instructions832to implement the method(s) ofFIG. 7may be stored in the mass storage device828, in the volatile memory814, in the non-volatile memory816, and/or on a removable tangible computer readable storage medium such as a CD or DVD.

From the foregoing, it will be appreciated that the above disclosed methods, apparatus and articles of manufacture enable real time communication of drilling information while drilling a borehole. Some examples disclosed herein employ an imaging system having an image sensor that captures images at a high frame rate. In some examples, the images are processed downhole to reduce, minimize and/or alleviate effects of motion parallax such as blurring. By employing image processing, the examples disclosed herein determine diverse types of drilling information such as characteristics of a subterranean formation, characterizations of downhole fluids, conditions and/or states of components of a drill bit assembly, and/or other drilling information.