Direction-finding and positioning system of electromagnetic emission of coal or rock fracture

Patent metadata

Field	Value
Publication number	US-11567230-B1
Application number	US-202217679137-A
Country	US
Kind code	B1
Filing date	Feb 24, 2022
Priority date	Sep 3, 2021
Publication date	Jan 31, 2023
Grant date	Jan 31, 2023

Abstract

A direction-finding and positioning system of electromagnetic emission of coal or rock fracture includes a three-axis electromagnetic sensor array, a signal acquisition module and a direction-finding and positioning terminal; the three-axis electromagnetic sensor array is composed of at least four three-axis electromagnetic sensors configured to synchronously sense magnetic field strength in three-axis direction based on a tunnel magneto resistance technology, and obtain a real magnetic field vector in space by measuring; the signal acquisition module is configured to acquire magnetic field vector variable information of multiple measuring points in real-time, and after extracting magnetic field vector variable parameters, transmitting the magnetic field vector variable parameters to the direction-finding and positioning terminal; the direction-finding and positioning terminal is configured to perform direction-finding and positioning calculations according to the magnetic field vector variable parameters received, and performing a three-dimensional dynamic visual display to positioning results, positioning time, and positioning coordinates.

First claim

What is claimed is:

1. A direction-finding and positioning system of an electromagnetic emission of a coal or rock fracture, comprising a three-axis electromagnetic sensor array, a signal acquisition module and a direction-finding and positioning terminal;
the three-axis electromagnetic sensor array is composed of at least four three-axis electromagnetic sensors, which are configured to synchronously sense a magnetic field strength in a three-axis direction based on a tunnel magneto resistance technology, and obtain a real magnetic field vector in space by measuring the magnetic field strength in the three axis direction;
the three-axis electromagnetic sensor comprises an auxiliary power source circuit, a three-axis sensing module, a waveform conditioning module, and an output circuit that are connected sequentially, the auxiliary power source circuit is connected to a power supply port, and the output circuit is connected to an axial output channel of the an x-axis, a y-axis, and a z-axis respectively;
the three-axis sensing module is composed of three micro-magnetic sensing chips arranged orthogonally through imposing by a PCB patch, the micro-magnetic sensing chip senses the magnetic field intensity components on the x-axis, the y-axis, and the z-axis based on a tunnel magneto resistance effect of a magnetic multilayer film material, and a voltage signal conversion is realized directly through a push-pull Wheatstone bridge circuit;
the signal acquisition module is configured to acquire magnetic field vector variable information of multiple measuring points in real-time, and after extracting magnetic field vector variable parameters, transmit the magnetic field vector variable parameters to the direction-finding and positioning terminal; and
the signal acquisition module comprises a multi-channel acquisition instrument and a controller;
the multi-channel acquisition instrument is configured to acquire the magnetic field vector variable information of the multiple measuring points in real-time, and transmitting acquisition data to the controller via wireless fidelity; and
the controller is configured to control an acquisition process and store data, and transmit the magnetic field vector variable parameters to the direction-finding and positioning terminal after extracting the magnetic field vector variable parameters;
the direction-finding and positioning terminal is configured to perform direction-finding and positioning calculations according to the magnetic field vector variable parameters received, and perform a three-dimensional dynamic visual display to positioning results, positioning time, and positioning coordinates;
the direction-finding and positioning terminal is further configured to:
step 1, establish an unified Cartesian coordinate system, a coordinate axis is parallel to a test axis of each three-axis electromagnetic sensor, and correct a corresponding relationship respectively between a positive direction of the three-axis electromagnetic sensor and a positive direction of the coordinate axis;
step 2, for an i-th three-axis electromagnetic sensor in the three-axis electromagnetic sensor array, construct a space vector n ix , n iy , and n iz along planes of three coordinate axes according to a spatial position of a measuring point where it is located, and construct a feature vector Hi according to a set of the magnetic field vector variable parameters (Ax, Ay, Az) extracted;
step 3, calculate three azimuth angles α, β, and γ of the real magnetic field vector at the position of the i-th third three-axis electromagnetic sensor:

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Assignees

• Univ Beijing Science & Technology

Inventors

• Song Dazhao
• He Xueqiu
• Wei Menghan

Classifications

• G01V3/38

  Processing data, e.g. for analysis, for interpretation, for correction · CPC title

• G01V3/165

  operating with magnetic or electric fields produced or modified by the object or by the detecting device (with electromagnetic waves G01V3/17) · CPC title

• G01V3/12 Primary

  operating with electromagnetic waves {(operating with millimetre waves G01V8/005)} · CPC title

• G01V3/081 Primary

  the magnetic field is produced by the objects or geological structures (characterised by the method of magnetic field measurement G01R33/00) · CPC title