Subsea Cable Layout Detection Using DAS Sea Wave Mapping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Offshore wind farm subsea composite cables often deviate from direct paths between turbines and can move due to undercurrents, making their exact layouts difficult to determine for planning and maintenance purposes.
Innovation Solution
Employ distributed fiber optic sensing (DFOS) systems combined with distributed acoustic sensing (DAS) and optional camera inputs to map pressure waves from sea waves, using mathematical algorithms to determine subsea cable layouts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If subsea cables are installed below the seabed to protect them, then cable protection and stability are improved, but the ability to detect and map cable layouts becomes more difficult
Solution Approach 1:
The patent uses sea waves as an intermediary medium to detect subsea cable layouts. The DAS system detects pressure waves generated by sea waves that propagate through water and interact with the subsea cables, even when buried. This intermediary approach allows indirect detection of cable positions without requiring direct visual access or exposing the cables.
Solution Approach 2:
The patent replaces traditional mechanical or visual inspection methods with acoustic wave-based detection. Instead of physically accessing or visually inspecting buried cables, the system uses distributed acoustic sensing to detect pressure wave patterns along the cable route, substituting mechanical detection with acoustic field-based measurement.
2Adaptability or versatility
If subsea cables are allowed to move due to undercurrents, then cable flexibility and adaptability are improved, but cable layout stability and predictability deteriorate
Solution Approach 1:
The patent acknowledges and adapts to the dynamic nature of subsea cable positions by continuously monitoring pressure wave patterns. Rather than assuming fixed cable positions, the system captures temporal variations in wave-cable interactions, allowing it to track and map cable layouts even when cables move due to undercurrents or other environmental factors.
Solution Approach 2:
The system uses feedback from pressure wave detection to continuously update and refine cable layout information. By analyzing the relationship between detected pressure waves and known sea wave patterns, the system can infer current cable positions and adjust its understanding of cable layouts in response to cable movements.
3Measurement precision
If DAS systems are used to detect pressure waves from sea waves, then cable layout detection capability is improved, but system complexity and data processing requirements increase
Solution Approach 1:
The patent leverages the universality of DAS technology, which was originally designed for other applications, and applies it to subsea cable detection. The same DAS infrastructure used for general acoustic monitoring can be repurposed to detect pressure waves from sea waves for cable layout mapping, reducing the need for specialized equipment while maintaining measurement precision.
Solution Approach 2:
The system creates a virtual model or copy of the cable layout by mapping pressure wave detection data to physical cable positions. Rather than directly observing cables, the system reconstructs cable layout information from acoustic signal patterns, creating an indirect but accurate representation of the physical system.
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
Accurately determines both relative and absolute subsea cable layouts, even when installed below the seabed, by integrating DAS data with visual inputs from cameras, enhancing planning and maintenance efficiency.
Implementation Method 1
distributed fiber optic sensing (DFOS) systems combined with distributed acoustic sensing (DAS) to map pressure waves from sea waves
Implementation Method 2
pressure changes due to the waves on the sea surface are still detected by our inventive systems and methods
Data Source
AI summary
Disclosed are systems and methods employing distributed fiber optic sensing (DFOS)/distributed acoustic sensing (DAS) in conjunction with mathematical algorithms, and an optional camera to determine layout of subsea cables. The subsea cables are pressure wave detectors of the DAS system and employ mathematical algorithms which map detected pressure waves to sea waves to determine subsea cable layout. When a subsea cable is installed below the seabed, pressure changes due to the waves on the sea surface are still detected. When DAS data is integrated with an optional camera visual input namely: a relative subsea cable layout may be determined by assuming a uniform planar sea wave propagating through the sea; an absolute cable layout may be determined by considering actual sea wave shape detected by the camera; and wave shapes may be determined based on a known subsea cable layout.