Cross bore detector for horizontal drilling machine and method

Abstract

A cross bore detector for a horizontal drilling machine to detect presence of a cross bore in an underground borehole comprises; a radar signal generator and radar signal receiver for generating a radar signal, a transmitting antenna coupled to the radar signal generator for transmitting the radar signal, the transmitting antenna including a planar base structure, a radiating element disposed on the planar base structure, and a magneto-dielectric antenna cover that covers the radiating element, multiple receiving antennas for receiving reflections of the radar signal; and an elongate downhole sensor housing having a longitudinal axis, the downhole sensor housing configured to receive the transmitting antenna, the multiple receiving antennas, and the radar signal generator therein. A method operates a cross bore detector system including the cross bore detector.

Description

Attorney Docket No: 489825-0012-W001CROSS BORE DETECTOR FOR HORIZONTAL DRILLING MACHINE AND METHODRELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 685,469, filed August 21, 2024, the entire content of which is hereby incorporated by reference.BACKGROUND

[0002] The arrangement relates to horizontal directional drilling (HDD) systems that are configured to drive a drill rod string into the ground for trenchless underground uti 1 ity installation. Although HDD systems allow steering of the drill head to avoid creating cross bores with existing underground utility installations, cross bores may be created when HDD drilling is performed in an area with an unknown existing underground utility installation. Confirming that cross bores have not been created by the new HDD drill bore can be burdensome, leading to increased job time and cost.

[0003] The arrangement provides improvements to and differs from commonly owned U.S. Patent No. 11.473,418 (the '418 patent), which is disclosed and incorporated by reference in its entirety.SUMMARY

[0004] In one aspect, a cross bore detector for a horizontal drilling machine to detect presence of a cross bore in an underground borehole comprises: a radar signal generator and receiver for generating a radar signal; a transmitting antenna coupled to the radar signal generator for transmitting the radar signal, the transmitting antenna including a planar base structure, a radiating element disposed on the planar base structure, and a magneto-dielectric antenna cover that covers the radiating element; multiple receiving antennas for receiving reflections of the radar signal; and an elongate downhole sensor housing having a longitudinal axis, the downhole sensor housing configured to receive the transmitting antenna, the multiple receiving antennas, and the radar signal generator therein.Attorney Docket No: 489825-0012-US01

[0005] In another aspect, a cross bore detection system for a horizontal drilling machine to detect presence of a cross bore in an underground borehole, comprises a cross bore detector. The cross bore detector includes: a transmitting antenna for transmitting radar signals; multiple receiving antennas for receiving reflections from the transmitted radar signals emitted from the transmitting antenna to provide data to an electronic module; an electronic module configured to receive the data from the receiving antennas and process the data for transmission in a data stream; and a downhole PLC module for transmitting the data stream. The cross bore detection further includes an uphole PLC module for receiving the data stream from the downhole module and transmitting the data stream; and a cloud-based device configured to receive the data stream of the reflected radar signals and process the data to detect presence or absence of a cross bore.

[0006] In one aspect, a method of operating a cross bore detector for a horizontal drilling machine to detect presence of a cross bore in an underground borehole comprises: transmitting radar signals from a transmitting antenna; receiving reflected radar signals emitted from the transmitting antenna using receiving antennas; providing a data stream from the received reflected radar signals; determining whether the cross bore detector is stationary to: prevent transmitting of the data stream of the radar signals to an external electronic processor when stationary, and transmit the data stream to the external electronic processor when the cross bore detector is moving. The method uses the data stream to detect presence of a cross bore at the external electronic processor.

[0007] In another aspect, a method of operating a cross bore detector for a horizontal drilling machine to detect presence of a cross bore in dry' and wet environments of an underground borehole comprises: selecting one from a group consisting of: a wet bore configuration for frequency band and frequency step points, and a dry bore configuration for frequency band and frequency step points, wherein the wet bore configuration is different from the dry bore configuration. The method moves the cross bore detector through an underground bore hole while: transmitting radar signals from the selected group from a transmitting antenna; receiving reflections from the transmitted radar signals emitted from the transmitting antenna using receiving antennas to provide a data stream; transmitting the data stream to anAttorney Docket No: 489825-0012-US01 electronic processor; and processing the data stream with the electronic processor to detect presence or absence of a cross bore.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Fig. 1 is a perspective view of a cross bore detector with the elongate downhole sensor housing removed, according to some examples.

[0009] Fig. 2 is a perspective view of a cross bore detector with the camera end cap and end cap components removed for purposes of illustration, according to some examples.

[0010] Fig. 3 is a perspective view of the cross bore detector with the camera end cap, circuit board carrier, receiving antennas carrier, and transmitting antenna carrier separated, according to some examples.

[0011] Fig. 4 is a perspective view of the cross bore detector 20 shown in Fig. 3, with receiving antennas and transmitting antenna removed from the receiving antennas carrier and the transmitting antenna carrier, respectively.

[0012] Figs. 5(A)-5(C) show perspective views of a construction of a receiving antenna / transmitting antenna, according to some examples.

[0013] Fig. 6 is a broken and cross-sectional view of the downhole sensor housing and the circuit board carrier, according to some examples.

[0014] Fig. 7 is a block diagram of a cross bore detection system that includes the cross bore detector and uphole components, according to some examples.

[0015] Fig. 8 is a detailed block diagram of the electronic module shown in Fig. 7, according to some examples.

[0016] Fig. 9 is a flow chart showing an operation of the cross bore detection system that prevents the transmission of a data stream when the cross bore detector is not moving, according to some examples.

[0017] Fig. 10 is a flow chart show ing a user operation of the cross bore detection system that accounts for a wet or dry bore hole, according to some examples.Attorney Docket No: 489825-0012-US01

[0018] Fig. 11 is a flow chart showing an operation of the cross bore detection system that accounts for a wet or dry bore hole, according to some examples.

[0019] Fig. 12 is a flow chart showing an operation of the cross bore detection system that automatically determines and accounts for a wet or dry bore hole, according to some examples.DETAILED DESCRIPTION

[0020] Before any examples, aspects, or features are explained in detail, it is to be understood that those examples, aspects and features are not limited in their application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. Other examples, aspects, and features are possible and are capable of being practiced or of being earned out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

[0021] Fig. 1 illustrates a cross bore detector 20 for horizontal directional drilling (HDD). A HDD machine operable to perform trenchless, directional-controlled underground drilling between two points, e.g., for utility installations, such as gas lines is disclosed in the '418 patent. A plurality of drill rod assemblies are sequentially connected end-to-end on the HDD machine to form a drill string. The drill string is driven into the ground by the HDD machine as described in the 418 patent.

[0022] The cross bore detector 20 shown in Fig. 1 includes a twisted pair of insulated wires 24 for power line communication (PLC). PLC refers to the method of transferring electrical power and data for communication through the same network of wires from one end to the other end. A utility connection 28 is provided at a first end for connection to a utility or other device. The utility connection 28 is screwed into a camera end cap 30.

[0023] The camera end cap 30 shown with parts separated in Fig. 2 includes a first camera 34 having a first lens 36 and four light emitting diodes 38 embedded in the camera end cap. The camera end cap 30 includes a second camera 44 having aAttorney Docket No: 489825-0012-US01 second lens 46. The camera end cap 30 includes apertures 48 for receiving the wires 24. The camera end cap 30 is secured to close an end of an elongate downhole sensor housing 50. The elongate downhole sensor housing 50 accounts for the protection of the interior devices. Further, the elongate downhole sensor housing 50 has a casing material which permits electromagnetic waves of the antenna to pass through.

[0024] In Fig. 1, the cross bore detector 20 includes a circuit board carrier 54, a receiving antennas carrier 58, and a transmitting antenna carrier 60. In Fig. 1 the carriers 54, 58, 60 are secured to each other. The circuit board carrier 54 includes a shell internal to an outer composite shell which holds all electronic components in place and secures to the camera end cap 30. The circuit board carrier manages wires to prevent data corruption from a motor of a cooling fan, from the transmitting and receiving antennas, and from cables to the light emitting diodes 38.

[0025] A drill string connection 68 and a second end cap 70 closes the other end of the elongate downhole sensor housing 50 that encloses the carriers 54, 58, 60. End cap 70 seals components within the elongate downhole sensor housing 50. A direction illustrated in Fig. 1 represents a pull back direction P for an assembled cross bore detector 20.

[0026] Fig. 3 shows the circuit board carrier 54, the receiving antennas carrier 58, and the transmitting antenna carrier 60 of the cross bore detector 20 as separated unassembled elements. The end of the camera end cap 30 shows electrical connectors 64 to supply electrical power and data to the circuit board carrier 54. The circuit board carrier 54 has slots 66 on one end to receive the electrical connectors 64, which are then attached by screws 69.

[0027] Fig. 3 shows that an opposing end of the circuit board earner 54 has slots 76 to receive electrical connectors 74 projecting outwardly from a first end of the receiving antennas carrier 58. Screws 78 attach the electrical connectors 74 to electrical contacts in the slots 76. An opposing end of the receiving antennas carrier 58 shows four receiving antennas 80, 82, 84, 86 projecting longitudinally to form a rectangular box shape with openings at comers thereof. The transmitting antenna carrier 60 includes a rounded receiver portion 88 having an inner opening configured to mate with the four receiving antennas 80, 82, 84, 86 of the receiving antennasAttorney Docket No: 489825-0012-US01 carrier 58 to join the receiving antennas carrier 58 with the transmitting antenna earner 60 as shown in Fig. 1. Thus, the receiving antennas 80, 82, 84, 86 have an end projecting outwardly and longitudinally from an end of the receiving antennas carrier 58. The receiving antennas carrier 58 interlocks with the transmitting antenna carrier 60 oriented in a direction defined by the longitudinal axis.

[0028] Fig. 4 shows the cross bore detector 20 with the four receiving antennas 80, 82, 84, 86 removed from the receiving antennas carrier 58. The four receiving antennas 80, 82, 84, 86 fit into slots in the receiving antennas carrier 58. The receiving antenna 80 is oriented transverse to the adjacent receiving antennas 82, 86 and parallel to the receiving antenna 84. Thus, the receiving antennas 80, 82, 84. 86 forming a box shape are oriented to cover a 360 degree field of view as each receiving antenna faces a different direction. The four receiving antennas are also spaced equidistantly from a longitudinal axis defined in a center of the elongate downhole sensor housing 50 and moving along the length thereof in a direction P shown in Fig. 1.

[0029] Fig. 3 also shows a transmitting antenna 90 disposed in the transmitting antenna carrier 60. The transmitting antenna 90 is at an angle offset from the receiving antennas 80, 82, 84, 86 relative to a longitudinal axis of the elongate downhole sensor housing 50. Fig. 4 shows the transmitting antenna 90 removed from the transmitting antenna carrier 60. Slots formed in the transmitting antenna carrier 60 receive the transmitting antenna 90. When assembled as shown in Fig. 1, the receiving antennas 80, 82, 84, 86 are almost adjacent the transmitting antenna 90 along a longitudinal axis / direction of the cross bore detector 20 corresponding to the pull back direction P shown in Fig. 1.

[0030] Fig. 5(A) illustrates in detail the transmitting antenna 90. The transmitting antenna 90 includes a planar base structure 92. In one example, the planar base structure 92 is generally a flat rectangular layer of glass epoxy. In another example, the planar base structure 92 is a thermoset plastic laminate, such as FR-4 that is electrically insulative. Other substrates or structures are contemplated.

[0031] The transmitting antenna 90 includes a transmission line 94 that connects to a radiating element 95. The radiating element 95 represents a grated monopoleAttorney Docket No: 489825-0012-US01 radiating element in one example. The transmission line 94 and the radiating element95 are formed from copper in one example. Other type of antennas, such as a dipole antenna are contemplated.

[0032] The transmitting antenna 90 includes an antenna cover 96 shown in Fig. 5(A) that is a magneto-dielectric antenna cover in one example. The antenna cover96 sandwiches the radiating element 95 between itself and the planar base structure 92 as shown in Fig. 5(B). The antenna cover 96 is fixed or bonded to the planar base structure 92, e.g., by epoxy or other adhesive. The antenna cover 96 is made from a high impedance laminate. In one example, the antenna cover 96 is made from a low loss, high resistivity ceramic filler and a high temperature thermoplastic matrix.Other materials are contemplated. The thickness of the antenna cover loads the transmitting antenna 90 to attempt to match the impedance with a drilling fluid (water, bentonite, or bentonite mixture with polymer). The magneto-dielectric antenna cover 96 is a substrate, superstrate, or both in this design. The elongate downhole sensor housing 50 is also made of a dielectric material or a magnetodielectric material in some examples.

[0033] The back of the transmitting antenna shown in Fig. 5(C) shows a U- shaped grounding plane 98. The grounding plane 98 is copper in one example. Other shapes are contemplated.

[0034] The receiving antennas 80, 82, 84, 86 correspond to the antenna structures shown in Figs. 5(A)-5(C) in one example. Multiple receiving antennas are contemplated. Four receiving antennas 80, 82, 84, 86 allow- for a symmetrical array of antennas w ith a box configuration to provide 360 degree reception and for direction finding. This specific orientation shown in Figs. 1, 3, and 4 minimizes the coupling between the transmitting antenna 90 and the receiving antennas 80, 82, 84, 86 (by inverting them to align their ground planes). Each of the receiving antennas 80, 82, 84, 86 is oriented parallel to an opposing non-adjacent receiving antenna.

[0035] Placing cross bore detector 20 including the receiving antennas 80, 82, 84, 86 and the transmitting antenna 90 inside the elongate downhole sensor housing 50 made of a dielectric material and placing downhole sensor housing 50 in fluid (water, bentonite) show s an improvement in the s-parameters compared to the downholeAttorney Docket No: 489825-0012-US01 sensor housing 50 being in freespace with the antennas 80, 82, 84, 86, 90 inside. This configuration shows more stability in the antenna parameters when the cross bore detector 20 (antennas, magneto-dielectric material and downhole dielectric sensor housing) is in the dielectric medium (water, bentonite) inside a borehole. Better stabi 1 i ty includes better impedance matching with the drilling fluid (w ater, bentonite, or bentonite mixture with polymer).

[0036] The cross bore detector 20 can be used on a drill head as a forwardlooking radar. The transmitting antenna w ould comprise the arrangement show n in Figs. 5(A)-5(C) followed by a hard ceramic cover (examples include zircona or alumina). On the backside of the transmitting antenna a magneto-dielectric material is provided and a reflector (drill cavity). To enhance bandwidth, split ring resonators are added to the radiating element of the transmitting antenna 90 in one example. This combination of split ring resonators, magneto-dielectric material and the dielectric protective cover can be used to miniaturize the antennas 80, 82. 84. 86. 90 and match the impedance to the drilling fluid for performance. Such an arrangement is useful in both a side looking and forw ard looking radar with a directional antenna. For a forward looking radar, the transmitting antennas 80, 82, 84, 86, 90 and the receiving antennas are oriented in a forward direction as a look-ahead transmitting antenna and as look-ahead receiving antennas

[0037] CIRCUIT BOARD CARRIER

[0038] Fig. 6 shows the circuit board carrier 54 disposed within a cross section of the downhole sensor housing 50. The circuit board carrier 54 supports multiple components including a downhole pow er line communication module 100 provided on a power line communication input / output board 102. Further, a heat sink 106 is provided to remove or transfer heat from components on various circuit boards within the circuit board carrier 54.

[0039] A radar signal generator and receiver 108 is provided on a circuit board. An electronic module 110 is provided on another electronic module circuit board 112. A cooling fan 114 is provided above the electronic module. The cooling fan 114 may include a heatsink.

[0040] CROSS BORE DETECTION SYSTEMAttorney Docket No: 489825-0012-US01

[0041] Fig. 7 is a block diagram illustration of a cross bore detector system 120, according to some examples. The cross bore detector 20 includes components shown in a broken line box. The cross bore detector includes receiving antennas 80, 82, 84, 86 for receiving reflected radar signals transmitted by the transmitting antenna 90. The radar signal generator and radar signal receiver 108 provides a radar signal to the transmitting antenna 90 and processes the reflected radar signals received by the receiving antennas 80, 82, 84, 86. The radar signal generator and radar signal receiver 108 can support a frequency range between 100 MHz and 6 GHz as well as various antenna configurations.

[0042] Fig. 7 shows an electronic module circuit board 112 that supports the electronic module 110, which is in communication with the radar signal generator and radar signal receiver 108, the downhole power line communication module 100, inertial measurement units 124, 126, a cooling fan 114, and light emitting diodes 38 for providing light for the cameras 34. 44, which communicate with the downhole power line communication module 100. In one example, the cooling fan 114 is a pulse width modulated (PWM) cooling fan.

[0043] The inertial measurement units 124, 126 are specialized as an attitude heading reference system for determining an accurate orientation of the cross bore detector 20. When paired with the linear displacement encoder 136 and other elements, the relative shape or geometry of the borehole can be determined. The inertial measurement units 124, 126 can also provide data streams from their respective onboard accelerometers, gyroscopes, and magnetometers. Thus, the inertial measurement units 124, 126 disposed in the elongate downhole sensor housing provide data to locate a position / orientation of the cross bore detector 20.

[0044] Besides the components of the cross bore detector 20 set forth above, the cross bore detector system 120 shown in Fig. 7 includes an uphole power line communication (PLC) module and processing device 130, a power supply 132, a linear displacement encoder 136, and data that is received from a horizontal directional drilling machine 138. Further, the uphole PLC module and processing device 130 communicates via a user interface device 140 to a cloud-based device 150. In another arrangement, the uphole PLC module and processing device 130 communicates wirelessly directly with a cloud-based device 150.Attorney Docket No: 489825-0012-US01

[0045] The user interface device 140 displays data about the bore site and from the cross bore detector 20. The user interface device 140 also acts as a controller of the cross bore detector system 120 by controlling toggling of a recording state in one example. The user interface device 140 also acts as a telematics device for providing data to and from the cloud-based device 150 in another example. The user interface device 140 is a tablet, a portable laptop, a desktop computer, a cell phone or other computing device having an electronic processor and a display in some examples.

[0046] The cloud-based device 150 can include one or more of computer devices, servers, external electronic processors, etc. In one example, MCAP files are used to store time stamped data received from the cross bore detector 20 in the cloud. YAML is a data serialization language that can be used in another example.

[0047] The linear displacement encoder 136 determines movement of the cross bore detector 20 from movement of the twisted pair of wires 24 connected to a spool above ground. Thus, the linear displacement encoder 136 determines when the cross bore detector 20 is or is not moving. Thereafter, the uphole PLC module and processing device 130 prevents sending of bore hole data to the cloud-based device 150 when there is no movement.

[0048] FIG. 8 illustrates the electronic module 110 for the cross bore detector 20 that includes an electronic processor 160 and one or more non-transitory, computer- readable memory modules, according to some examples. In the example of FIG. 8, the electronic module 110 includes a random access memory (“RAM7’) 164 and a read-only memory (“ROM”) 168. The electronic module 110 also includes an input / output interface 170 that transmits and receives data over a controller area network (“CAN”) bus or other electrical connections / links including ethemet to other devices and modules. It should be understood that the electronic module 110 can include multiple processors, additional computer-readable memories, multiple I / O interfaces, and / or additional components or modules (e.g., hardware, software, or a combination thereol).

[0049] The electronic processor 160 receives information from the I / O interface 170 and processes the information by executing instructions for one or more software modules (which may also be referred to as a “controller” or “controllers”) stored to aAttorney Docket No: 489825-0012-US01 memory of the electronic module 110, such as the read only memory (ROM) 168. The electronic processor 160 stores information to and retrieves information from the random access memory (RAM) 164 (e.g., information received from other subsystems or sensors through the controller area network (CAN) bus or ethemet and information generated by modules executed by the electronic processor 160). The non-transitory computer readable memory of the electronic module 110 includes volatile memory, non-volatile memory, or a combination thereof and. in various constructions, may also store operating system software, applications / instructions data, and combinations thereof.

[0050] The downhole power line communication module 100, the radar signal generator and radar signal receiver 108, and the uphole PLC module and processing device 130 each may include an electronic processor, a random access memory', a read-only memory, and an input / output interface in a similar manner as the electronic module 110 for communication therebetween and various separate constructions, including operating system software, applications / instructions data, and combinations thereof.

[0051] BASIC OPERATION

[0052] The uphole PLC module and processing device 130 supplies power from the power supply 132 to cross bore detector 20 including the downhole PLC module 100, the radar signal generator and radar signal receiver 108, the electronic module 110, the cameras 34, 44, and the inertial measurement units 124, 126. The power is further provided to other components. Data communication is also provided over the tw isted pair of insulated wires 24 providing the power.

[0053] In the illustrated example, the cameras 34. 44 are digital Ethemet cameras such that the system is provided as a video monitoring system. The camera 34, 44 allows direct observation of the borehole, and this can be implemented for providing real time uphole video monitoring, although the video data may also be recorded and saved. Further details are discussed in the 418 patent.

[0054] The downhole PLC module 100 is connected to the cameras 34, 44 through Ethemet connections in one example. As such, the downhole PLC module 100 is operable to receive the data output (e.g., video of a suitable format) of theAttorney Docket No: 489825-0012-US01 cameras 34, 44 and transform the data for transmission to the uphole PLC module and processing device 130 throughout a pullback operation in one example. In this example, the cross bore detector 20 is attached to a drill string at an exit point for detecting cross bores during pullback of the drill string.

[0055] Simultaneously with the camera, the radar signal generator and radar signal receiver 108 operates to provide a step frequency continuous wave (SFCW) that is transmitted via the transmitting antenna 90. The step frequencies can be configured for different boreholes without changing the transmitting antenna 90. Since the radar and antenna are ultra-wide band, multiple frequency bands can be configured for different borehole conditions without swapping antennas. Radar has the capability to operate from 100 MHz to 6GHz. In one example, the transmitting antenna 90 transmits in the 400 MHz to 1.2 GHz band with the monopole transmitting antenna. Thus, ultra-wide band signals are utilized. With another transmitting antenna, a range of 400 MHz to 6 GHz is provided.

[0056] The receiving antennas 80, 82, 84, 86 receive reflections from the transmitted radar signals emitted from the transmitting antenna 90 to provide data to the electronic module 110. The electronic module 110 processes and in some examples, time stamps the data to provide a data stream. The electronic module 110 also receives data streams from the inertial measurement units 124, 126 that is processed to provide a data stream. The electronic module also provides device operational status information for the various components of the cross bore detector 20. The data streams are transmitted via the downhole PLC module 100 to the uphole PLC module and processing device 130. As discussed above the PLC module and processing device 130 transfers the data streams and data to the user interface device 140 directly in one example. The user interface device 140 transfers the data streams and data to the cloud-based device 150 via a wireless connection. The wireless connection includes cellular and satellite connections, for example.

[0057] In another example, the uphole PLC module and processing device 130 wirelessly transfers the data streams and data to the cloud-based device 150 directly. The cloud-based device 150 communicates with the user interface device 140.Attorney Docket No: 489825-0012-US01

[0058] In one example, the data stream and / or data is processed by the cloudbased device 150 to detect the presence of a cross bore. In other examples, processing of the camera and radar data may be performed by the downhole PLC module 100, by the uphole PLC module and processing device 130, or by the electronic module 110. The camera and radar data may be processed in real-time or may be post processed after the pull back operation is complete or a drilling of a bore hole with a drill head is completed.

[0059] In another example, an electronic processor interprets the radar signals from the antennas 80, 82, 84, 86 in order to create a borehole map, besides operating to “see’?the borehole, e.g.. in order to detect a presence or absence of a cross bore. The system may also include bore-mapping hardware useful for producing an as-built three dimensional bore map which can be synchronized with the cross bore detector system 120 to produce a cross bore location.

[0060] OPERATING ARRANGEMENTS

[0061] Fig. 9 shows one operating method for the cross bore detector system 120 that prevents the transmission of a data stream when the cross bore detector 20 is not moving, according to some examples. In operation, at step 204 the radar signal generator and radar signal receiver 108 provides a radar signal to the transmitting antenna 90 for transmission therefrom. Thereafter, at step 208 the reflected radar signals are received by the receiving antennas 80, 82, 84, 86. The receiving antennas 80, 82, 84, 86 provide the reflected radar signals to the radar signal generator and radar signal receiver 108. The radar signal generator and radar signal receiver 108 provides a data stream to the electronic module 110. The data stream is provided to the downhole PLC module 100 for sending to the cloud-based device 150.

[0062] After the data stream is obtained at step 208, the method advances to decision step 212. At step 212, the cross bore detector system 120 determines whether the cross bore detector 10 is moving at a given useful speed such that a cross bore hole can be determined from the data stream. When the cross bore detector 20 is not moving, the arrangement advances to step 216. In one example, the cross bore detector 20 is not moving when a position determining device provides a position data stream corresponding to a position of the cross bore detector 20 moving in theAttorney Docket No: 489825-0012-US01 underground bore hole. In one instance, the position determining device is the linear displacement encoder 136 that does not detect changes corresponding to movement thereof. In another example, the cross bore detector 20 is not moving when the positioning device is an inertial measurement unit 126 does not detect movement thereof. In another example, the position determining device is part of a drilling machine that provides drilling data as to a position of the cross bore detector.

[0063] At step 216, the cross bore detector system 120 prevents transmission of the data stream. In one example, the preventing of the transmission of the data stream of the radar signals to an external electronic processor of the cloud-based device 150 occurs for time periods when the linear displacement encoder 136 does not detect changes corresponding to movement of the cross bore detector 20.

[0064] In another example at step 216, the preventing of the transmission of the data stream of the radar signals to the external electronic processor of the cloud-based device 1 0 occurs for time periods when the inertial measurement unit 126 does not detect movement of the cross bore detector 20. In another example, the time periods are when the drilling data from the drilling machine does not indicate a change in position of the cross bore detector 20.

[0065] Returning to decision step 212, when the cross bore detector system 120 determines that the cross bore detector 20 is moving using one or more of the arrangements set forth above, the method advances to step 220. At step 220, the data stream is transmitted via the radar signal generator and radar signal receiver 108, the electronic module 110, the downhole PLC module 100, and the user interface device 140 to an external electronic processor of the cloud-based device 150. Thus, the external electronic processor is remote from the cross bore detector 20.

[0066] After step 220, the method advances to step 224. At step 224, the external processor of the cloud-based device 150 detects the presence or absence of a cross bore based on the data stream of reflected radar signals.

[0067] Besides preventing the transmission of the data stream, the method is provided to delete or overwrite the data stream as the data stream does not change when the cross bore is stationary or not moving.Attorney Docket No: 489825-0012-US01

[0068] OPERATION IN WET / DRY ENVIRONMENT

[0069] Fig. 10 shows a flow chart of a method of manually programming operation of a radar signal generator and radar signal receiver 108, according to some examples. In a first step 254, a user interacts with an input keyboard or touchscreen of the user interface device 140 to select providing of parameters for use by the radar signal generator and radar signal receiver 108.

[0070] The algorithm or program stored in the user interface device 140 then advances to step 258. At step 258, the user selects or adjusts a frequency band value. Advancing to step 262, the user selects frequency step points. Thereafter, at step 266, the user selects a resolution bandwidth for use by the radar signal generator and radar signal receiver 108.

[0071] After advancing to step 270, the user selections are saved by the user interface device 140 and transferred to the cross bore detector 20 for storage in memory in either of the electronic module 110 and the radar signal generator and radar signal receiver 108.

[0072] The frequency band, the frequency step points and the resolution bandwidth are selected based on whether the borehole is wet or dry. The frequency step points are selected frequency values that provide the accurate results for the wet or dry conditions expected in the borehole. The desired frequency band, the frequency step points, and the resolution bandwidth differ depending on whether the borehole is wet or dry. Thus, different values are loaded and stored for the different environment modes.

[0073] Fig. 1 1 shows a flow chart 280 wherein a user determines the conditions of a borehole, according to some examples. In a first step 284, a user interacts with an input keyboard or touchscreen of the user interface device 140 to begin operation of the cross bore detector system 120. The program advances to step 288 wherein a user selects either a wet condition or a dry condition environment mode for the borehole. Depending on the selection, at step 292 the user interface device 140 provides mode specific configuration for frequency band, frequency step points, and resolution bandwidth that are retrieved from a memory of the user interface device 140. One instance is a wet bore configuration for frequency band, frequency steps,Attorney Docket No: 489825-0012-US01 and resolution bandwidth. Another selection is a dry bore configuration for frequency band, frequency steps, and resolution bandwidth. Thereafter, at step 296, the radar signal generator and radar signal receiver 108 of the cross bore detector 20 loads the selected radar configuration for operation at the frequency band, frequency step points and resolution bandwidth provided therewith.

[0074] When loaded, the user operates the user interface device 140 to direct the cross bore detector system 120 to begin outputting radar signals at the step points from the transmitting antenna 90 in the selected mode / configuration. The multiple receiving antennas 80, 82, 84, 86 receive reflected radar signals and the cross bore detector system 120 detects the presence or absence of cross bores as discussed above and as shown in Fig. 9 and elsewhere.

[0075] AUTOMATIC DEVICE ENVIRONMENT MODE

[0076] Fig. 12 shows a flow chart 300 wherein a wet bore hole or dry bore hole is automatically and initially determined by the cross bore detector system 120, according to some examples. In a first step 304, a user interacts with an input keyboard or touchscreen of the user interface device 140 to select an automatic device environment detection mode for operation of the cross bore detector system 120. No further inputs are provided by a user.

[0077] The radar signal generator and radar signal receiver 108 outputs a radar signal. The cross bore detector system 120 determines from the data received whether the bore hole is wet or dry at step 308. Thereafter, at decision step 312, when a target signal corresponding to a specific frequency band, frequency step points, and resolution bandwidth for one from the group consisting of a wet borehole configuration or a dry borehole configuration is selected / determined, the arrangement advances to step 316 wherein the frequency step points are executed.

[0078] In an instance when a wet or dry bore hole is not determined at decision step 312. the method returns to step 308 and receives additional data from a different radar signal as a different target to again attempt determine whether the borehole is wet or dry.Attorney Docket No: 489825-0012-US01

[0079] Upon a correct determination, the mode operation is complete at step 316 and the wet bore configuration or dry bore configuration is automatically provided to the radar signal generator and radar signal receiver 108 of the cross bore detector system 120 to automatically operate the system. Each configuration includes an appropriate frequency band, frequency steps, and resolution bandwidth.

[0080] In conclusion, after a user selects an automatic device environment detection mode, the cross bore detector system 120 operates to select one from a group consisting of: a wet bore configuration and a dry bore configuration performed by initially determining from the radar data received by the receiving antennas that an underground drilling borehole is wet or dry. and thereafter automatically selecting the wet bore or dry bore configuration depending on the initial determination. When an initial determination fails, the automatic device environment detection mode reattempts at a different radar frequency to determine a status of the bore hole.

[0081] OTHER FEATURES

[0082] One example includes a cross bore detection system 120 to be used during a utility installation pull back operation, with design considerations to improve radar functionality in a wet bore hole and maintain dry bore hole functionality.

[0083] In some examples, processing camera data and radar data streams may be performed on the downhole PLC module 100. on the uphole PLC module and processing device 130, or on another system such as a cloud-based device 150. The camera data and radar data stream may be processed in real-time or may be post processed after the pull back operation is complete. Thus, in some instances, the camera data and radar data stream are stored by the cross bore detection system 120 for later uploading to the cloud-based device 150.

[0084] Examples of additional sensors for the cross bore detector 20 that are not shown herein include: strain gauge(s), pressure transducer(s), and temperature sensor(s). Such instruments and / or sensors may be used in crossbore detection and / or for separate purposes.

[0085] In view of the accuracy of the cross bore detector system 120 including the radar signal generator and radar signal receiver 108. in one example the cross boreAttorney Docket No: 489825-0012-US01 detector 20 is free from having a camera 34, 44 disposed therein. In this example, the cameras 34, 44 and light emitting diodes 38 are not provided. The camera end cap 30 continues to provide electrical connections for the transfer of power and data therethrough.

[0086] In another example, a dipole antenna design is used in dry borehole environments. The dipole antennas are used for radar frequencies between 3 GHz and 6 GHz. In one example, two dipole transmitting antennas and four dipole receiving antennas are used. In this arrangement, the dipole transmitting and receiving antennas are provided in transmitting and receiving carriers that replace the receiving antennas carrier 58 and the transmitting antenna carrier 60 within the elongate downhole sensor housing 50.

[0087] In another example, the cross bore detector 20 includes a radar configured as a MIMO (Multiple Input and Multiple Output) radar for imaging inside a borehole utilizing at least 2 transmitting antennas with vertical and horizontal polarization and multiple receiving antennas. In another example, the multiple receiving antennas are each defined as an independent channel and process each in-phase signal and quadrature signal for every frequency step point for each of the receiving antennas 80, 82, 84, 86.

[0088] In another example, data from the linear displacement encoder 136 is used in conjunction with the inertial measurement units 124, 126, and the data stream of the radar signals (used to facilitate bore map creation) is transferred to the uphole power line communication module and processing device 130. From there, all data is transferred to the user interface device 140, which transfers all the raw data to the cloud-based device 150 via a cellular connection. The data is stored in data tables in the cloud and used for cross bore detection processing and bore map creation. The processed data, including a simple representation of any detected cross bores and associated cross bore locations on the bore map, is then transferred from the cloudbased device 150 to the user interface device 140 for review;

[0089] In addition, unless the context of their usage unambiguously indicates otherwise, the articles “a” and “an’’ should not be interpreted as meaning “one” orAttorney Docket No: 489825-0012-US01“only one.” Rather these articles should be interpreted as meaning “at least one” or “one or more.”

[0090] Also, it should be understood that the illustrated components, unless explicitly described to the contrary, may be combined or divided into separate software, firmware, and / or hardware. For example, instead of being located within and performed by a single electronic processor, logic and processing described herein may be distributed among multiple electronic processors. Similarly, one or more memory7modules and communication channels or networks may be used even if examples described or illustrated herein have a single such device or element. Also, regardless of how they are combined or divided, hardware and software components may be located on the same computing device or may be distributed among multiple different devices. Accordingly, in this description and in the claims, if an apparatus, method, or system is claimed, for example, as including a controller, control module, control unit, electronic processor, computing device, logic element, module, memory module, communication channel or network, or other element configured in a certain manner, for example, to perform multiple functions, the claim or claim element should be interpreted as meaning one or more of such elements where any one of the one or more elements is configured as claimed, for example, to make any one or more of the recited multiple functions, such that the one or more elements, as a set. perform the multiple functions collectively.

[0091] Although certain examples, features, and aspects have been described and illustrated, variations and modifications exist within the scope and spirit of the subject matter explained and shown.

Claims

Attorney Docket No: 489825-0012-US01CLAIMSWhat is claimed is:

1. A cross bore detector for a horizontal drilling machine to detect presence of a cross bore in an underground borehole comprising: a radar signal generator and radar signal receiver for generating a radar signal; a transmitting antenna coupled to the radar signal generator for transmitting the radar signal, the transmitting antenna including a planar base structure, a radiating element disposed on the planar base structure, and a magneto-dielectric antenna cover that covers the radiating element; multiple receiving antennas for receiving reflections of the radar signal; and an elongate downhole sensor housing having a longitudinal axis, the downhole sensor housing configured to receive the transmitting antenna, the multiple receiving antennas, and the radar signal generator therein.

2. The cross bore detector of claim 1. wherein the radiating element is a grated monopole radiating element.

3. The cross bore detector of claim 1, wherein the multiple receiving antennas each include a planar base structure, a radiating element, and a magneto-dielectric antenna cover that covers the radiating element.

4. The cross bore detector of claim 3, wherein the radiating element of the multiple receiving antennas is a grated monopole radiating element.

5. The cross bore detector of claim 1, wherein the multiple receiving antennas include four receiving antennas symmetrically disposed from the longitudinal axis.

6. The cross bore detector of claim 5. wherein the four receiving antennas are spaced equidistantly from the longitudinal axis.

7. The cross bore detector of claim 6, wherein the receiving antennas are disposed transverse to adjacent ones of the receiving antennas.Attorney Docket No: 489825-0012-US018. The cross bore detector of claim 7, wherein each said receiving antenna is oriented parallel to an opposing non-adjacent receiving antenna.

9. The cross bore detector of claim 5, wherein the four receiving antennas are disposed in a receiving antennas carrier that is disposed in the elongate downhole sensor housing, and wherein the transmitting antenna is disposed in a transmitting antenna carrier.

10. The cross bore detector of claim 9, wherein the receiving antennas carrier interlocks with the transmitting antenna carrier oriented in a direction defined by the longitudinal axis.

11. The cross bore detector of claim 5, wherein the transmitting antenna is a first transmitting antenna and the cross bore detector includes a second transmitting antenna.

12. The cross bore detector of claim 1, including an inertial measurement unit disposed in the elongate downhole sensor housing for providing data to locate a position / orientation of the elongate downhole sensor housing in an underground borehole.

13. The cross bore detector of claim 1, including a circuit board carrier supporting a pow er line communication module, the radar signal generator and radar signal receiver on a circuit board, a heat sink, and a cooling fan, wherein the circuit board carrier is disposed in the elongate downhole sensor housing.

14. The cross bore detector of claim 13, wherein the cooling fan transfers heat to a surface of the elongate downhole sensor housing.

15. The cross bore detector of claim 1, including an electronic module for receiving the radar signals from the multiple receiving antennas and providing the radar signals to an external electronic processor via pow er line communication over a pair of insulated wires.Attorney Docket No: 489825-0012-US0116. The cross bore detector of claim 1, including attaching the elongate dow nhole sensor housing to a drill head to detect a cross bore during drilling of a bore hole, and wherein the transmitting antenna and the receiving antennas are oriented in a forward direction as a look-ahead transmitting antenna and as look-ahead receiving antennas.

17. The cross bore detector of claim 1, wherein the cross bore detector is attached to a drill string at an exit point for detecting cross bores during pullback of the drill string.

18. The cross bore detector of claim 1, wherein the cross bore detector is free from having a camera.

19. A cross bore detection system for a horizontal drilling machine to detect presence of a cross bore in an underground borehole, comprising: a cross bore detector including: a transmitting antenna for transmitting radar signals; multiple receiving antennas for receiving reflections from the transmitted radar signals emitted from the transmitting antenna to provide data to an electronic module; an electronic module configured to receive the data from the receiving antennas and process the data for transmission in a data stream; and a downhole PLC module for transmitting the data stream, an uphole PLC module for receiving the data stream from the downhole module and transmitting the data stream; and a cloud-based device configured to receive the data stream of the reflected radar signals and process the data to detect presence or absence of a cross bore.

20. The cross bore detection system of claim 19, further including a user interface device for receiving the data stream from the uphole PLC module and wirelessly transmitting the data stream to the cloud-based device.

21. The cross bore detection system of claim 20, wherein the uphole PLC module receives a position data stream from a position determining device that detects a position of the cross bore detector moving through an underground bore hole.Attorney Docket No: 489825-0012-US0122. The cross bore detection system of claim 21 . wherein the position determining device is a linear displacement encoder.

23. The cross bore detection system of claim 21, wherein the position determining device is part of a drilling machine that provides drilling data as to a position of the cross bore detector.

24. The cross bore detection system of claim 20, wherein the user interface device is one from a group consisting of a computer tablet and a laptop computer.

25. The cross bore detection system of claim 20, wherein the cross bore detector includes a radar signal generator and radar signal receiver for generating the transmitted radar signals, the transmitted radar signal having a frequency band and frequency step points.

26. The cross bore detection system of claim 25, wherein the multiple receiving antennas include four receiving antennas for receiving reflections of the radar signal.

27. The cross bore detection system of claim 20, wherein a radar signal generator and radar signal receiver receives the reflected radar signals from each of the multiple receiving antennas defined as an independent channel and processes each in-phase signal and quadrature signal for every frequency step point for each of the receiving antennas.

28. A method of operating a cross bore detector for a horizontal drilling machine to detect presence of a cross bore in an underground borehole comprising: transmitting radar signals from a transmitting antenna; receiving reflected radar signals emitted from the transmitting antenna using receiving antennas; providing a data stream from the received reflected radar signals; determining whether the cross bore detector is stationary to: prevent transmitting of the data stream of the radar signals to an external electronic processor when stationary, andAttorney Docket No: 489825-0012-US01 transmit the data stream to the external electronic processor when the cross bore detector is moving; and detecting presence of a cross bore at the external electronic processor.

29. The method of claim 28, wherein the external electronic processor is a cloudbased device.

30. The method of claim 28, wherein the preventing of transmission of the data stream of the radar signals to the external electronic processor occurs for time periods when a linear displacement encoder does not detect changes corresponding to movement of the cross bore detector.

31. The method of claim 30, wherein a radar signal generator and radar signal receiver receives and separates the reflected radar signals from each of the receiving antennas into an independent channel and processes each in-phase signal and quadrature signal for every frequency step point for each of the receiving antennas to form the data stream.

32. The method of claim 30, wherein the external electronic processor receives and separates the reflected radar signals from each of the receiving antennas into an independent channel and processes each in-phase signal and quadrature signal for every' frequency step point for each of the receiving antennas to form the data stream.

33. The method of claim 30, wherein an electronic module receives and separates the reflected radar signals from each of the receiving antennas into an independent channel and processes each in-phase signal and quadrature signal for every frequency step point for each of the receiving antennas to form the data stream.

34. The method of claim 28, wherein the cross bore detector includes an inertial measurement unit for determining movement of the cross bore detector, and wherein the preventing transmitting of the data stream of the radar signals to the external electronic processor occurs for time periods when the inertial measurement unit does not detect movement of the cross bore detector.Attorney Docket No: 489825-0012-US0135. The method of claim 28, wherein the radar signals are ultra-wide band signals.

36. A method of operating a cross bore detector for a horizontal drilling machine to detect presence of a cross bore in dry and wet environments of an underground borehole comprising: selecting one from a group consisting of: a wet bore configuration for frequency band and frequency step points, and a dry bore configuration for frequency band and frequency step points, wherein the wet bore configuration is different from the dry bore configuration; and moving the cross bore detector through an underground bore hole while: transmitting radar signals from the selected group from a transmitting antenna; receiving reflections from the transmitted radar signals emitted from the transmitting antenna using receiving antennas to provide a data stream; transmitting the data stream to an electronic processor; and processing the data stream with the electronic processor to detect presence or absence of a cross bore.

37. The method of claim 36, wherein the selecting of the group is provided by a manual input by a user of the cross bore detector.

38. The method of claim 36, wherein the selecting of the group is provided by a user selecting an automatic device environment detection mode, wherein the selecting one from a group consisting of: a wet bore configuration and a dry bore configuration is performed by a cross bore detector system initially determining from the data received by the receiving antennas that an underground drilling borehole is wet or dry , and automatically selecting the wet bore or dry bore configuration depending on the initial determination.

39. The method of claim 36, wherein the receiving antennas include four antennas.

40. The method of claim 39, wherein a radar signal generator and radar signal receiver receives and separates the reflected radar signals from each of the receivingAttorney Docket No: 489825-0012-US01 antennas into an independent channel and processes each in-phase signal and quadrature signal for every frequency step point for each of the receiving antennas to form the data stream.

41. The method of claim 36, wherein the radar signals are ultra-wide band signals.

42. The method of claim 36, wherein the transmitting antenna is a first transmitting antenna and the cross bore detector includes a second transmitting antenna.

43. The method of claim 36, including an inertial measurement unit for providing data to locate a position of the cross bore detector in an underground borehole.

44. The method of claim 36, wherein the electronic processor is an external processor remote from the cross bore detector.

45. The method of claim 36, wherein the electronic processor is a cloud-based device.

46. The method of claim 45, the method including: storing the data from the receiving antennas for later delivery to the electronic processor when a communication link to the cloud-based device is not available.

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