Patent Publication Number: US-2023135275-A1

Title: System and method for mapping a borehole using lidar

Description:
FIELD OF THE DISCLOSURE 
     The present disclosure relates generally to mappings using light detection and ranging (LIDAR), and, more particularly, to a system and method for mapping a borehole using LIDAR. 
     BACKGROUND OF THE DISCLOSURE 
     In the oil and gas industry, the use of light beams has been limited to high power applications. Such high power applications are typically destructive, and so have been used for drilling, perforating, and descaling of boreholes, wells, casings, etc. Low power applications of light beams can include LIDAR. LIDAR can employ lasers. The low power applications are not destructive and are less costly to operate. However, such low power applications in the oil and gas industry have not included surface and downhole inspection and evaluation. 
     SUMMARY OF THE DISCLOSURE 
     According to an embodiment consistent with the present disclosure, a system and method map a borehole using LIDAR. 
     In an embodiment, a system comprises a tool and a mapping sub-system. The tool has a longitudinal length extending along a longitudinal axis of the tool, with the tool configured to be positioned in a borehole. The term ‘borehole’ refers to the inner wall of a well or surface pipelines, regardless of the media, and so can include the wall of a rock formation in an open-hole environment or a cased hole in which metallic or nonmetallic tubular structures line the hole. The tool includes an intermediate LIDAR sub-system and a distal LIDAR sub-system. The intermediate LIDAR sub-system is disposed at an intermediate position along the longitudinal length, with the intermediate LIDAR sub-system having an intermediate emitter and an intermediate receiver. The intermediate emitter emits light in a first direction which is towards an intermediate object in the borehole, and the intermediate receiver receives reflected light from the intermediate object to determine a characteristic of the intermediate object. The distal LIDAR sub-system is disposed at a distal position of the tool, with the distal LIDAR sub-system having a distal emitter and a distal receiver. The distal emitter emits light in a second direction which is towards a distal object in the borehole, and the distal receiver receives reflected light from the distal object to determine a characteristic of the distal object. The mapping sub-system has code therein configured to determine a position of the tool in the borehole from the characteristic of the distal object, to determine an inner surface of the borehole from the characteristic of the intermediate object, and to generate and output a map of the borehole from the position and the inner surface. 
     Either of the intermediate emitter and the distal emitter is omni-directional. The tool can rotate about the longitudinal axis as either of the intermediate emitter and the distal emitter emits the light. The intermediate object is a portion of the inner surface of the borehole. The mapping sub-system includes an output device configured to display the map to a user. 
     In another embodiment, a system comprises a tool and a mapping sub-system. The tool has a longitudinal length extending along a longitudinal axis of the tool, with the tool configured to be positioned in a borehole. As should be understood, positioning in a borehole includes positioning within the inner wall of a well or surface pipelines, regardless of the media, and so can include positioning within the wall of a rock formation in an open-hole environment or in a cased hole in which metallic or nonmetallic tubular structures line the hole. The tool includes an intermediate LIDAR sub-system and a distal LIDAR sub-system. The intermediate LIDAR sub-system is disposed at an intermediate position along the longitudinal length, with the intermediate LIDAR sub-system having an intermediate emitter and an intermediate receiver. The intermediate emitter emits light in a first direction which is towards an intermediate object in the borehole, and the intermediate receiver receives reflected light from the intermediate object to determine an intermediate distance of an intermediate portion of the tool from the intermediate object. The distal LIDAR sub-system is disposed at a distal position of the tool, with the distal LIDAR sub-system having a distal emitter and a distal receiver. The distal emitter emits light in a second direction which is towards a distal object in the borehole, and the distal receiver receives reflected light from the distal object to determine a distal distance of a distal portion of the tool from the distal object. The mapping sub-system has code therein configured to determine a position of the tool in the borehole from the distal distance, to determine an inner surface of the borehole from the intermediate distance of the intermediate object, and to generate and output a map of the borehole from the position and the inner surface. 
     Either of the intermediate emitter and the distal emitter is omni-directional. The tool can rotate about the longitudinal axis as either of the intermediate emitter and the distal emitter emits the light. The intermediate object is a portion of the inner surface of the borehole. The mapping sub-system includes an output device configured to display the map to a user. 
     In a further embodiment, a method comprises extending a tool in a borehole, emitting a plurality of light beams from the tool toward a plurality of objects in the borehole, receiving reflected light beams from the objects, determining a plurality of distances of the objects by multiplying the round trip travel times of the emitted light beams and the reflected light beams with one half of the value of the speed of light, mapping an inner surface of the borehole and the objects in the borehole using the distances to generate a map of the inner surface and the objects, generating a three-dimensional representation of the inner surfaces and objects using the map, and outputting the three-dimensional representation from an output device. 
     The light beams can be emitted omni-directionally. At least one object is a portion of the inner surface. The light beams are emitted from a LIDAR device on the tool. The LIDAR device can emit the light beams omni-directionally. The tool can rotate to direct the emitted light beams onto the objects positioned around the tool. 
     Any combinations of the various embodiments and implementations disclosed herein can be used in a further embodiment, consistent with the disclosure. These and other aspects and features can be appreciated from the following description of certain embodiments presented herein in accordance with the disclosure and the accompanying drawings and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    illustrates a logging tool in a borehole, according to an embodiment. 
         FIG.  2    illustrates a logging tool in a borehole, according to an alternative embodiment. 
         FIG.  3    is a schematic of a system using the logging tools of  FIGS.  1 - 2   . 
         FIG.  4    is a flowchart of operation of the system of  FIG.  3   . 
     
    
    
     It is noted that the drawings are illustrative and are not necessarily to scale. 
     DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS OF THE DISCLOSURE 
     Example embodiments consistent with the teachings included in the present disclosure are directed to a system and method for mapping a borehole using LIDAR. 
     Referring to  FIG.  1   , a tool  10  has a longitudinal length extending along a longitudinal axis of the tool  10 , with the tool  10  configured to be positioned in a borehole  12 . The tool  10  includes an intermediate LIDAR sub-system  14  emitting light  16 , and a distal LIDAR sub-system  18  emitting light  20 . The light  16 ,  20  can be laser light. The intermediate LIDAR sub-system  14  is disposed at an intermediate position along the longitudinal length of the tool  10 . The distal LIDAR sub-system  18  is disposed at a distal position of the tool  10 . The light  16  can be directed omni-directionally. The light  20  can be directed generally distally away from the tool  10 . 
     In an alternative embodiment shown in  FIG.  2   , a tool  30  has a longitudinal length extending along a longitudinal axis of the tool  30 , with the tool  30  configured to be positioned in a borehole  12 . The tool  30  includes an intermediate LIDAR sub-system  34  emitting light  36 , and a distal LIDAR sub-system  38  emitting light  40 . The light  36 ,  40  can be laser light. The intermediate LIDAR sub-system  34  is disposed at an intermediate position along the longitudinal length of the tool  30 . The distal LIDAR sub-system  38  is disposed at a distal position of the tool  30 . The light  36  is emitted in a limited arc from the tool  30 . The tool  30  can rotate about an axis  32 . In an alternative embodiment, the tool  30  can have a body which is stationary and does not rotate, while the sub-systems  34 ,  38  rotate about the axis  32 . 
     During rotation of the tool  30  or the sub-systems  34 ,  38 , the light  36  can sweep about the tool  30 , and so is directed omni-directionally from the tool  30 . The light  40  can be directed generally distally away from the tool  30  in a predetermined arc. During rotation of the tool  30 , the light  40  can be directed in an expanded arc about the distal end of the tool  30 , with the expanded arc being greater than the predetermined arc. Accordingly, using rotation of the tool  30  and movement of the tool  30  through the borehole  12 , the LIDAR sub-systems  34 ,  38  sweep a wide range of objects surrounding the tool  30 . Such sweeps of LIDAR from the tool  30  can form a spiral pattern of detection of objects in the borehole  12 . 
     Referring to  FIG.  3   , a system  50  includes an intermediate LIDAR sub-system  52 , such as described above, and a distal LIDAR sub-system  54 , such as described above. The intermediate LIDAR sub-system  52  and the distal LIDAR sub-system  54  are communicatively coupled to a mapping sub-system  56 . For example, the sub-systems  52 ,  54  can be connected to the mapping sub-system  56  by a transmission line extending through the longitudinal length of the tool  10 ,  30 . Alternatively, the sub-systems  52 ,  54  can be wirelessly connected to the mapping sub-system  56 . 
     The intermediate LIDAR sub-system  52  has an intermediate emitter  58  and an intermediate receiver  60 . The intermediate emitter  58  can be a laser. The intermediate receiver  60  can be a photodiode. The intermediate emitter  58  emits light in a first direction which is towards an intermediate object in the borehole  12 , and the intermediate receiver  60  receives reflected light from the intermediate object to determine a characteristic of the intermediate object. The distal LIDAR sub-system  54  has a distal emitter  62  and a distal receiver  64 . The distal emitter  62  can be a laser. The distal receiver  60  can be a photodiode. The distal emitter  62  emits light in a second direction which is towards a distal object in the borehole  12 , and the distal receiver  64  receives reflected light from the distal object to determine a characteristic of the distal object. 
     The mapping sub-system  56  includes a hardware processor  66 , a memory  68 , and an output device  70 . The hardware processor  66  has code therein configured to determine a position of the tool  10 ,  30  in the borehole  12  from the characteristic of the distal object, to determine an inner surface of the borehole  12  from the characteristic of the intermediate object, and to generate and output a map of the borehole  12  from the position and the inner surface. The hardware processor  66  can be a microprocessor. The memory  68  can store the code as well as data representing the position, information on the inner surface, and the map. The output device  70  can be a display which can output the position data, the information on the inner surface, and the map. 
     As shown in  FIG.  4   , a method  100  includes a LIDAR sub-system emitting a pulse of light toward objects in a borehole  12  in step  102 , and determining, using a programmed processor as described above, a travel time of the pulse of light from the emitter to the objects and back to a receiver in step  104 . The travel time is used to determine a plurality of distances of the objects by multiplying the round trip travel times of the emitted light beams and the reflected light beams with one half of the value of the speed of light. The method  100 , using a programmed processor, then determines a position of the tool  10 ,  30  in the borehole  12  in step  106 . The method  100  then collects the determined position data within a memory, as indicated at step  108 , and maps an inner surface and surroundings of the borehole  12  from the position data in step  110 , using code executing in the processor to arrange the position data in the positions so-determined. The method  100  also determines physical characteristics of the borehole  12  in step  112 . The physical characteristics can include the volume of portions of the borehole  12 . These determinations, like others, are done using a processor that is configured by code executing therein. The method  100  then generates and outputs a map which visually displays the borehole  12  and the determined physical characteristics of the borehole  12  in step  114 . The map is used to generate a three-dimensional representation of the inner surfaces and objects. The three-dimensional representation is output from the output device  70 . Such generation of a map and a three-dimensional representation of a borehole using LIDAR can be performed by a system and method as described in U.S. Patent Publication No. US 2021/0183224 A1, which is incorporated herein by reference. 
     Portions of the methods described herein can be performed by software or firmware in machine readable form on a tangible (e.g., non-transitory) storage medium. For example, the software or firmware can be in the form of a computer program including computer program code adapted to cause the system to perform various actions described herein when the program is run on a computer or suitable hardware device, and where the computer program can be embodied on a computer readable medium. Examples of tangible storage media include computer storage devices having computer-readable media such as disks, thumb drives, flash memory, and the like, and do not include propagated signals. Propagated signals can be present in a tangible storage media. The software can be suitable for execution on a parallel processor or a serial processor such that various actions described herein can be carried out in any suitable order, or simultaneously. 
     It is to be further understood that like or similar numerals in the drawings represent like or similar elements through the several figures, and that not all components or steps described and illustrated with reference to the figures are required for all embodiments or arrangements. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “contains”, “containing”, “includes”, “including,” “comprises”, and/or “comprising,” and variations thereof, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     Terms of orientation are used herein merely for purposes of convention and referencing and are not to be construed as limiting. However, it is recognized these terms could be used with reference to an operator or user. Accordingly, no limitations are implied or to be inferred. In addition, the use of ordinal numbers (e.g., first, second, third) is for distinction and not counting. For example, the use of “third” does not imply there is a corresponding “first” or “second.” Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” “having,” “containing,” “involving,” and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. 
     While the disclosure has described several exemplary embodiments, it will be understood by those skilled in the art that various changes can be made, and equivalents can be substituted for elements thereof, without departing from the spirit and scope of the invention. In addition, many modifications will be appreciated by those skilled in the art to adapt a particular instrument, situation, or material to embodiments of the disclosure without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, or to the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. 
     The subject matter described above is provided by way of illustration only and should not be construed as limiting. Various modifications and changes can be made to the subject matter described herein without following the example embodiments and applications illustrated and described, and without departing from the true spirit and scope of the invention encompassed by the present disclosure, which is defined by the set of recitations in the following claims and by structures and functions or steps which are equivalent to these recitations.