Spectral Imaging Powered Ship Hull Biofouling Detection and Cleaning

Project Information

SleekShip

Grant agreement ID: 950854

DOI

10.3030/950854

Project closed

EC signature date 10 March 2020

Start date 1 April 2020

End date 31 July 2022

Funded under

• Horizon 2020 Framework Programme

Total cost

€ 3 088 475,00

EU contribution

€ 2 362 038,14

Coordinated by

SUBSEA TECH SAS
France

Periodic Reporting for period 2 - SleekShip (Spectral Imaging Powered Ship Hull Biofouling Detection and Cleaning)

Reporting period: 2021-08-01 to 2022-07-31

Summary of the context and overall objectives of the project

Biofouling on ship hulls is a long time and well-known challenge that has a direct impact on vessels drag and fuel consumption, representing more than 600 M€ of extra expenses per year for the maritime industry and consequently very significant additional gas emissions. Besides, not cleaned fouling on long haul vessels fosters the spreading of invasive species, which may be harmful to local marine life. This has resulted in more and more stringent regulations in some countries willing to preserve their marine environment.

Detecting very early stages of Level of Fouling (LoF 0-1, thin slime) is essential as it already increases vessel drag but can be cleaned with a soft method avoiding damaging the hull coating. This approach means that the detection and cleaning system has to be very cost effective and user friendly to avoid increasing the maintenance expenses for the ship owners.

The ambition of the SleekShip project is to propose a novel approach to ship hull cleaning by allowing early detection of this biofouling and cost-effective and soft cleaning of the hulls using a single unmanned underwater robotic system specially designed to reach the objectives both in terms of technical performance and production costs.

The SleekShip consortium has 5 partners, two high tech SMEs: Subsea Tech (SST - France) specialized in underwater robotics, QCell (QCL - Greece) focusing on hyperspectral imaging, one Research Centre: TWI Hellas (THL - Greece) working on navigation control and two end users: M.Danchor (MDR - Israel) a diving company dealing with ship hull maintenance and DANAOS (DNOS - Cyprus) a container ships manager.

The SleekShip technical work programme is articulated around four technical developments:
- An underwater hyperspectral camera capable of capturing optical information in different wavelengths moving beyond the visible spectrum and thus detecting very low levels of fouling. Besides, the hyperspectral technology performs better than standard RGB cameras in turbid waters and this will allow inspection in usually murky harbour environments.
- A cavitation jetting system modified to be integrated on a light underwater robotic system, allowing cleaning operations without damaging hull coatings. Such a system is complemented by a debris suction and filtering device to avoid spreading the fouling in the environment, as required by many national regulations.
- A specially designed underwater robot or ROV (Remotely Operated Vehicle) capable of supporting both the hyperspectral imaging camera and the cleaning tool with a production cost under 30 k€ per unit to compete efficiently with diver operations.
- A semi-automatic navigation software with cruise control algorithms to enhance the performance of the system and relieve the ROV operator from tedious piloting tasks. Such software will upgrade the ROV into a SAUV (Supervised Autonomous Underwater Vehicle) using a set of internal and external navigation sensors.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The works performed by the SleekShip partners during the elapsed period (M1 to M28) are the following:
- The system definition has been extensively discussed between partners who came up with the system functional specifications and preliminary operational procedures.
- QCL have developed and manufactured the underwater hyperspectral camera and integrated it on the mini Tortuga ROV. A special image processing algorithm has been developed to enhance vision in turbid waters, eliminating the water particles between the camera and the target. After lab tests using sample plates, real tests and validation have been made during Marseilles (France), Ashdod (Israel) and Piraeus (Greece) trials.
- Based on the existing Tortuga inspection class ROV, SST have designed and manufactured a lighter and cheaper vehicle capable of carrying the hyperspectral camera and the cleaning system. Named “mini Tortuga”, this new vehicle has been manufactured in 3 working units (+1 mock-up for dissemination) used extensively during development and test phase in Marseilles as well as demos and validation in M.Danchor’s Ashdod and Danaos’ Piraeus sites.
- THL have developed the smart cruise control algorithm which runs on the on-board computer and allows the ROV to automatically follow the ship hull. As selected sensors such as proximity detectors and short baseline positioning have not been performing as expected, it has been decided to combine auto depth mode and bearing on hull to allow automatic hull following in horizontal lines.
- Dissemination media such as website (www.sleekship.eu) social media accounts, brochures and advertising supports have been created as planned, all based on a proper brand guidelines document. All partners have been involved in dissemination activities.
- SST have worked in expanding their existing distribution network in order to ensure the promotion of the future products. Marketing actions including attendance to trade fairs, workshops and specific demos have been undertaken to allow the early commercialization of the system. Additional marketing actions are being pursued beyond the end of the project.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Several results have been achieved beyond the state of the art such as:
- An underwater hyperspectral camera and its associated software allowing detection and characterization of ultra-low levels of biofouling, beyond the visible spectrum.
- A compact and lightweight ROV (15 kg) capable of supporting the hyperspectral camera and a cavitation cleaning lance in water currents up to 3 knots.
- A semi-automated navigation system using auto depth and DVL sensor to follow ship hull in horizontal lines.

The SleekShip project has clearly several potential impacts:
As stand-alone products, these results will have a direct impact on SST and QCL competitiveness in their respective markets, namely underwater hyperspectral cameras and compact inspection class ROVs.
As a complete system, SleekShip units will contribute to reducing the shipping industry fuel expenses and gas emissions by removing biofouling in its early stage. The early cleaning operation will also lower the risks of spreading invasive marine species and endangering local ones.
Finally, its unmanned architecture will allow conducting complete diverless operations, including in contaminated and murky waters, thus reducing the human risk at sea and improving the workers’ safety.

SleekShip Mini Tortuga