# US 2013/0153299 A1 · Establishing positions of locating field detectors and path mapping in underground boring tool applications > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0153299 A1 - Document ID: US20130153299A1 - Status: Published application - Kind: A1 - Application number: 13/765,544 - Filed: 2013-02-12 - Published: 2013-06-20 - Earliest claimed: 1997-04-16 - Assignees: Merlin Technology, Inc. - Inventors: Guenter W. Brune; Peter H. Hambling; John E. Mercer; Lloyd A. Moore; Shiu S. Ng; Rudolf Zeller - Web page: https://patentgrep.com/patent/US20130153299A1 ## CPC - B82Y 25/00: Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance - E21B 47/0232: at least one of the energy sources or one of the detectors being located on or above the ground surface - E21B 7/046: {horizontal drilling (drilling with mechanical conveying means E21B7/003)} - G01R 33/093: {using multilayer structures, e.g. giant magnetoresistance sensors (thin magnetic films H01F10/00)} - G01V 3/081: {the magnetic field is produced by the objects or geological structures (characterised by the method of magnetic field measurement G01R33/00)} - G01V 3/38: Processing data, e.g. for analysis, for interpretation, for correction - H01Q 1/04: Adaptation for subterranean or subaqueous use - H01Q 1/36: Structural form of radiating elements, e.g. cone, spiral, umbrella; {Particular materials used therewith}(H01Q1/08, H01Q1/14 take precedence) - H01Q 1/38: formed by a conductive layer on an insulating support {(patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142)} - H01Q 7/00: Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop - H01Q 21/205: {providing an omnidirectional coverage (turnstile aerials H01Q21/26)} - H01Q 21/28: Combinations of substantially independent non-interacting antenna units or systems {(multiple beam H01Q25/00)} - H01Q 21/29: Combinations of different interacting antenna units for giving a desired directional characteristic (H01Q25/00 takes precedence) - G01V 3/165: operating with magnetic or electric fields produced or modified by the object or by the detecting device (with electromagnetic waves G01V3/17) - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) - H01Q: ANTENNAS, i.e. RADIO AERIALS (radiators or antennas for microwave heating H05B6/72) ## Abstract Specific apparatus and associated methods are described for use in establishing the positions of locating field detectors and for path mapping within a region for the purpose of tracking and/or guiding the movement of an underground boring tool. In one aspect, an improvement is provided forming part of an arrangement for tracking the position and/or guiding the boring tool using an electromagnetic locating signal which is transmitted from the boring tool as the boring tool moves through the ground. At least two detectors are located at fixed positions within the region, each being operable in a transmit mode and in a receive mode such that each one of the detectors in the transmit mode is able to transmit a relative locating signal to the other detector for use in determining the relative position of one detector in relation to the other and such that both detectors receive the electromagnetic locating signal in the receive mode for use in determining the position of the boring tool within the region. Provisions are also described for extending drilling range by using additional detectors by moving a limited number of detectors. In another aspect, a system is provided including at least two above ground detectors for sensing the locating signal. The detectors are located at initial positions in the region. Electromagnetic data is generated by the detectors with the boring tool at multiple positions to generate electromagnetic data which is used to identify the positions of the detectors. A selected flux pathline steering technique is introduced. ## Claims ### Claim 1 In a system for tracking the position of a transmitter in the ground as the transmitter moves along an underground path which lies within a region, said transmitter being configured for transmitting an electromagnetic locating signal, a method for establishing an intended path for the transmitter within said region, said method comprising: a) with the transmitter at a start position, positioning at least two above ground detectors at initial fixed positions within a dipole range of said transmitter in an initial portion of said region for receiving the electromagnetic locating signal as the transmitter is later guided along an initial segment of the intended path within said dipole range of said transmitter; b) establishing coordinates of said detectors within the initial portion of said region; c) mapping the initial segment of the intended path through the initial portion of said region in a particular way using said detectors; d) moving the detectors in a predetermined way to new locations within an adjacent, new portion of said region including an adjacent, new segment of said intended path; and e) without moving the transmitter from its start position, mapping the new segment of the intended path in said particular way through the new portion of said region through which the transmitter will later pass after having passed through the initial portion of the region. ### Claim 2 (depends on 1) The method of claim 1 further comprising: f) repeating steps (d) and (e) in an iterative manner for additional new segments of said intended path until a complete intended mapped path is established for the transmitter through said region, including segments of said intended path which are out of range of the dipole signal with the transmitter remaining at said start position. ### Claim 3 (depends on 2) The method according to claim 2 wherein the segments of the intended path are mapped in said particular way by (i) providing a mapping tool which is configured for transmitting a mapping signal to said detectors, (ii) positioning the detectors within one portion of the region undergoing mapping and corresponding to a particular segment of said intended path, (iii) positioning the mapping tool on or above the ground at a plurality of above ground points corresponding to the intended path for the particular segment while transmitting the mapping signal from each above ground point to the detectors in a way which establishes the coordinates of each above ground point and, thereby, establishes the coordinates of a corresponding point along the intended path of the transmitter in the particular segment. ### Claim 4 (depends on 1) The method according to claim 1 wherein establishing coordinate positions of the detectors within the initial portion of said region includes transmitting the electromagnetic locating signal from the transmitter at the start position and receiving the electromagnetic locating signal using the detectors to produce electromagnetic data and, thereafter, using information including the electromagnetic data to establish the coordinate positions of the detectors within said region. ### Claim 5 (depends on 1) The method according to claim 1 including configuring at least one of said detectors for transmitting a relative locating signal and configuring the other detector for receiving the relative locating signal and wherein moving the detectors in said predetermined way includes (i) moving a first one of the detectors to a first new location in the new portion of said region while the other detector remains in its initial, known position, and (ii) transmitting said relative locating signal between the detectors for use in establishing the first new location of the first detector so as to also establish the coordinate position of the first detector at said first new location in the new portion of the region. ### Claim 6 (depends on 5) The method according to claim 5 wherein the relative locating signal includes a maximum transmission distance between the detectors such that each segment of the intended path includes a length which is determined by said maximum transmission distance. ### Claim 7 (depends on 5) The method according to claim 5 wherein moving the detectors in said predetermined way further includes (i) moving the second one of the detectors to a second new location in the new portion of said region such that both detectors are in the new portion of the region and, thereafter, (ii) transmitting said relative locating signal between the detectors for use in establishing the second new location of the second detector so as to also establish the coordinate position of the second detector in the new portion of the region without the need to move the transmitter.