Magnetometer-Based Conduit Sensor Positioning Without GPS
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining the absolute velocity and position of a sensor device within a fluid conduit are inadequate, particularly for free-floating and non-free floating sensor devices, especially in underground or metallic environments where GPS is not effective.
Innovation Solution
A method involving a sensor device with first and second magnetometers, where magnetic flux data is collected and a time delay between magnetic signals in each magnetometer is determined, allowing for the calculation of absolute velocity and subsequent determination of distance traveled and sensor position.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If GPS and inertial navigation unit are used to determine position, then position accuracy is improved for above-ground conduits, but the method becomes inapplicable for underground or metallic conduit environments
Solution Approach 1:
The patent replaces GPS (electromagnetic satellite positioning) with a magnetic field-based positioning system using magnetometers. The sensor device uses magnetometers to detect magnetic flux from ferromagnetic conduit features, enabling position determination in underground and metallic environments where GPS fails. This substitutes an electromagnetic satellite-based system with a magnetic field sensing system adapted to the specific environment.
Solution Approach 2:
The patent introduces ferromagnetic features (such as magnetic markers or the conduit structure itself) as intermediaries between the magnetometer and the positioning system. These ferromagnetic features create detectable magnetic flux patterns that the magnetometer uses to determine position, serving as a mediator that enables positioning in environments where direct satellite signals cannot penetrate.
2Loss of information
If sensor device travels along the wall of the conduit, then position tracking is enabled, but background noise increases and friction is introduced
Solution Approach 1:
The patent separates the position determination function from the physical contact with conduit walls. Instead of requiring the sensor device to travel along the wall (physical contact), the device uses magnetometers to detect magnetic flux patterns from ferromagnetic features, enabling position tracking through magnetic field sensing without mechanical contact. This segments the positioning function from the mechanical travel function.
3Measurement precision
If odometer wheels are used on a pig to track distance, then position determination is achieved, but the device complexity increases and requires specific mechanical features
Solution Approach 1:
The patent replaces mechanical odometer wheels with a magnetic field-based distance measurement system. The magnetometer detects magnetic flux patterns from ferromagnetic features along the conduit, and by measuring the time delay or phase difference in signal arrival at multiple magnetometers, the system calculates distance and position without mechanical contact or moving parts.
Solution Approach 2:
The patent uses ferromagnetic features as intermediaries to enable distance measurement. Instead of mechanical wheels counting rotations, the system detects magnetic flux patterns from ferromagnetic markers or conduit features, using the magnetic field as a mediator to transfer position information to the sensor device.
4Measurement precision
If multiple sensor devices with tethering are used to determine position, then position can be calculated, but the setup complexity increases and implementation difficulty rises
Solution Approach 1:
The patent creates a universal positioning solution that works for both free-floating and wall-mounted sensor devices using the same magnetic field-based method. The system uses magnetometers to detect magnetic flux from ferromagnetic features, and position is determined through signal processing algorithms that work regardless of the sensor device's mechanical configuration or method of travel through the conduit.
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 enables accurate determination of absolute velocity and position of the sensor device, even in challenging environments, thereby improving the accuracy of fluid conduit inspections and property determinations.
Implementation Method 1
receiving sensor data collected by a sensor device during a measurement run from an interior of a fluid conduit... the sensor data including magnetic flux data comprising first magnetic flux data collected by the first magnetometer and second magnetic flux data collected by the second magnetometer
Data Source
AI summary
Systems, methods, and devices for fluid conduit inspection using absolute velocity of a sensor device are provided. The method includes: receiving sensor data collected by a sensor device during a measurement run from an interior of the fluid conduit while traveling along a length of the fluid conduit, the sensor device including a first magnetometer and a second magnetometer each having a fixed position in the sensor device, the fixed positions defining a separation distance between the first magnetometer and second magnetometer, the sensor data including magnetic flux data comprising first magnetic flux data collected by the first magnetometer and second magnetic flux data collected by the second magnetometer; determining a time delay between when a magnetic signal is present in the first magnetic flux data and when the magnetic signal is present in the second magnetic flux data; determining an absolute velocity of the sensor device.