Subsea Sensor Redeployment Using AUV and Service Station
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current subsea monitoring techniques for geological structures face challenges such as inaccurate deployment and high operational costs, especially in time-lapse monitoring where sensors need to be precisely redeployed at the same spot, and existing methods require extensive vessel operations and can harm marine life.
Innovation Solution
A system comprising an automated underwater vehicle (AUV) and a subsea service station, where sensors have a permanently installed base unit and a removable control unit, allowing the AUV to autonomously connect and disconnect the control unit for transportation between the base unit and the service station for charging, updating, and redeployment, reducing the need for surface communication and power lines.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If sensors are permanently installed at fixed locations for time-lapse monitoring, then measurement precision is improved, but device complexity and operational costs increase due to requiring dedicated cable handling vessels and extensive deployment operations
Solution Approach 1:
The sensor system is divided into separate components: a permanently installed base unit remaining at the original location and a removable control unit that can be detached and transported by AUV. This segmentation allows the critical positioning element (base unit) to stay fixed for measurement precision while the control unit is moved for maintenance and updates without requiring complex vessel operations
Solution Approach 2:
The AUV autonomously performs deployment, retrieval, and transport of control units between sensors and service station without human intervention. The system serves itself by using autonomous vehicles instead of dedicated cable handling vessels, eliminating the need for extensive deployment operations and reducing operational complexity
2Measurement precision
If dedicated cable handling vessels are used for sensor deployment and retrieval, then sensor redeployment accuracy is improved, but loss of time and operational costs increase due to requiring extensive vessel operations
Solution Approach 1:
The mechanical system of cable handling vessels is replaced with autonomous underwater vehicles (AUVs) that can autonomously transport control units. This substitution dramatically reduces the time required for sensor maintenance and redeployment, allowing more frequent surveys while maintaining accuracy through the permanently installed base units
Solution Approach 2:
The base units are permanently installed at precise locations beforehand, establishing accurate measurement positions in advance. When control units need maintenance, only the removable portion is transported, allowing rapid replacement and minimizing survey interval time while preserving the pre-established accurate positioning
3Reliability
If towed seismic sources are used for monitoring, then measurement capability is improved, but object-affected harmful factors increase due to adverse effects on marine life and operational constraints
Solution Approach 1:
The harmful towed seismic source operation is extracted and replaced with seafloor-mounted sources that generate acoustic signals. This eliminates the need to tow powerful sources through the water column, reducing adverse effects on marine life while maintaining the capability to generate necessary acoustic signals for monitoring geological structures
4Reliability
If control units are permanently fixed with wired connections for power and communication, then reliability is improved, but device complexity and operational costs increase due to requiring surface communication infrastructure
Solution Approach 1:
The system transitions from static wired connections to dynamic wireless communication between AUVs and control units. Power is supplied through the removable connector during AUV docking, eliminating the need for permanent underwater cables and surface communication infrastructure, thereby reducing complexity while maintaining operational reliability
Data Source
AI summary
A system (1) for operating a subsea sensor field (2), comprises an automated underwater vehicle—AUV (10) and a subsea service station (13). A sensor (11, 12) in the sensor field (2) comprises a permanently installed base unit (11) and a removable control unit (12). The AUV (10) moves control units (12) to the service station (13) for charging and updating, and then back to the base units.