Magnetic Sensor Package for Underground Object Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods fail to accurately determine the position and size of underground magnetic sources, such as existing piping, during drilling operations due to limitations in detecting magnetic fields with existing equipment and techniques, especially in crowded underground spaces where previous surveys may be unavailable or inaccurate.
Innovation Solution
A process utilizing a magnetic sensor package to measure three vector components of the magnetic field and an accelerometer, determining the gravity vector, and using parametric models to resolve and adjust for the earth's magnetic field, allowing for the subtraction of the earth's field from the total magnetic field to isolate and locate underground magnetic objects, and iteratively refining model parameters for a best fit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If existing equipment and techniques are used to detect magnetic fields, then the detection process is simple, but the measurement precision of underground magnetic source position and size is insufficient
Solution Approach 1:
The patent segments the magnetic field measurement into three orthogonal vector components (X, Y, Z) measured by separate sensors. This segmentation allows for more precise determination of the total magnetic field vector and its orientation, directly improving measurement precision for locating underground magnetic sources while maintaining manageable device complexity through modular sensor arrangement.
Solution Approach 2:
The patent introduces gravity vector measurement as an intermediary step to establish the vertical reference direction. By measuring the gravity vector with accelerometers and using it to resolve magnetic field components into horizontal and vertical parts, the system achieves more accurate positioning of underground magnetic sources without requiring direct complex magnetic field analysis alone.
2Difficulty of detecting and measuring
If magnetic field measurements are taken along a well path to locate underground piping, then the detection capability is improved, but the complexity of resolving magnetic field components and determining earth's field variations increases
Solution Approach 1:
The patent performs preliminary measurements of the earth's magnetic field along the well path before attempting to locate underground magnetic sources. By establishing a baseline model of earth's field variations in advance and subtracting it from total magnetic field measurements, the system simplifies the detection process for underground sources while improving detection capability through systematic data processing.
Solution Approach 2:
The patent changes the reference frame parameters by resolving magnetic field vectors from the sensor's local coordinate system into earth-fixed coordinate systems using gravity vector information. This parameter transformation simplifies the interpretation of magnetic field data and improves detection capability by separating earth's field components from anomaly components in a standardized reference frame.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method effectively determines the location and attitude of underground magnetic objects by isolating their magnetic field from the earth's field, providing accurate positioning and avoiding underground piping during drilling operations.
Implementation Method 1
determining the vector components of a total magnetic field vector at each of a plurality of measured depth locations along a well path
Implementation Method 2
determining the direction of the gravity vector at each of said plurality of locations along the well path
Implementation Method 3
using the determined direction of the gravity vector at each location to resolve the determined total field vector components into resolved horizontal and vertical components of the total field
Implementation Method 4
subtracting the determined earth magnetic field from the measured total magnetic field along the well path to obtain a determined magnetic field of the underground object
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method to determine the earth's magnetic field vector along a sub-surface wellpath having unknown and possibly changing azimuth, in the presence of a magnetic disturbance caused by a magnetic source external to the wellpath includes estimating the three components of the earth field along the three axes of a magnetic sensor package by a polynomial function of measured depth along the wellpath. Upon removal of the earth's magnetic field from the measurements, the resultant magnetic field of the disturbance is determined and can be used to determine the position and orientation of the source of the disturbance.