Underwater AUV Handover Using Acoustic Positioning

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The use of autonomous underwater vehicles (AUVs) for long-term work in water bodies is hindered by the need for frequent charging and positioning accuracy issues, leading to increased work time and vehicle size due to the requirement for large capacity batteries and transponders as markers.

Innovation Solution

Implementing a system where a second AUV replaces the first AUV, allowing for continuous operation without large capacity batteries and eliminating the need for transponders by using acoustic positioning and target detection for precise replacement and navigation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Duration of action of moving object

If a large capacity battery is mounted on the underwater vehicle to enable long-term work without charging, then the work time is extended, but the vehicle size increases which adversely affects operability

Engineering Contradiction:
Improvework timeVSAvoidvehicle size
Core Design Contradiction:
Duration of action of moving objectVSVolume of moving object

Solution Approach 1:

The system divides the work into multiple segments performed by different AUVs. Instead of one AUV performing all work continuously, multiple AUVs with standard battery capacities work in sequence, each completing a portion of the task before returning for charging. This eliminates the need for any single AUV to have a large capacity battery while maintaining continuous operation.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent combines multiple AUVs into a coordinated system where they work together to achieve long-term operational capability. By merging the capabilities of multiple smaller AUVs, the system achieves the equivalent of a single large-capacity battery AUV without the size penalty, as each AUV maintains standard dimensions for optimal operability.

Inventive Principle:
Principle #5Merging (Combining)

2Duration of action of moving object

If the underwater vehicle returns to the surface ship for charging during long-term work, then the vehicle can continue operation, but the work is suspended during the return and charging time which increases total work time

Engineering Contradiction:
Improvecontinuous operation capabilityVSAvoidwork suspension time
Core Design Contradiction:
Duration of action of moving objectVSLoss of time

Solution Approach 1:

The work is segmented into multiple portions that can be performed by different AUVs. When one AUV needs to return for charging, another AUV can immediately take over and continue the work without interruption. This segmentation of both work tasks and vehicle operations eliminates work suspension time while maintaining continuous progress.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system ensures continuous useful action by having multiple AUVs available to perform work. While one AUV is returning for or undergoing charging, another AUV is simultaneously performing work tasks. This overlapping of charging operations with work operations eliminates gaps in productivity and maintains continuous progress on the mission objectives.

Inventive Principle:
Principle #20Continuity of useful action

3Measurement precision

If a transmitter is installed at the work suspension spot to enable the underwater vehicle to return to the spot, then the vehicle can resume work accurately, but the complexity and cost of the system increases

Engineering Contradiction:
Improvepositioning accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

Instead of installing physical transmitters at work suspension spots, the system creates a virtual copy of the positioning information by having the AUV transmit its location data and work status. The AUV uses acoustic positioning to determine its location relative to the surface ship and other AUVs, then communicates this information to resume work at the correct position without requiring permanent transmitter installations at each work spot.

Inventive Principle:
Principle #26Copying

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 approach reduces work time, minimizes AUV size, and eliminates the need for transponders, enabling efficient and accurate long-term underwater operations without battery size increases or marker installations.

Implementation Method 1

an acoustic positioning device configured to measure a relative position of the first underwater vehicle relative to the second underwater vehicle

Methodology Applied
Scientific EffectAcoustic positioning: Sound

Implementation Method 2

a target detector configured to detect a work target and acquire a position of the work target relative to the second underwater vehicle

Methodology Applied
Scientific EffectTarget detection:

Data Source

PatentEP3851367B1Underwater vehicle system and working method
Publication Date: 2024.07.10 KAWASAKI JUKOGYO KK
  • EP3851367B1 patent drawingFigure 1
  • EP3851367B1 patent drawingFigure 2
  • EP3851367B1 patent drawingFigure 3~4

AI summary

An underwater vehicle system (100) according to one aspect of the present invention includes: a first underwater vehicle (10) configured to perform work in water while moving in a predetermined proceeding direction; and a second underwater vehicle (30) configured to replace the first underwater vehicle (10) and perform work in water. When the second underwater vehicle (30) replaces the first underwater vehicle (10), the second underwater vehicle (30) approaches the first underwater vehicle (10) based on a signal transmitted from the first underwater vehicle (10).