Deep sea infrastructure: ROV M. Musumeci KM3NET meeting Paris October 2008

Talk outline Quick overview of the state of the art for ROV market; The PEGASO project; Status of PEGASO project

General requirements The management of deep sea infrastructure foreseen inspection and intervention system able to satisfy the following “requirements”: To be able to execute in a flexible and cost-effective way the sea operation for the deployment, recovery, connection, disconnection and eventually for inspection and maintenance of the deep sea infrastructure during the life time of the Deep Sea Telescope; To be manage by ship of medium dimension and complexity simple to be find out and rent on the European market.

What a deep sea intervention system should do? The main requirements for deep sea intervention system for a deep sea detector should be: Deployment and recovery of detection units (string, tower, …) Deployment and recovery of Junction Boxes Connection and disconnection of the detctionunits/JB on the sea bed; Connection and disconnection of multidisciplinary deep sea scientific station (like SN-1,..) Periodical inspection of the KM3 infrastructure; Maintenance of the infrastructure (?) - TBD

Which is the smartest solution? The definition of the requirements for this system should have a strong influence on the characteristic of the system itself as weight, power supply, dimensions, manipulator, ecc, ….). Lesson learned coming from NEMO deep sea operation and probably also from ANTARES operations indicate the necessity to have light and flexible deep sea intervention system such as GENERAL CLASS ROV or LIGHT WORK CLASS ROV instead of huge WORKING CLASS system.

What is an ROV A Remotely Operated Vehicle (ROV) as an underwater robot that allows the vehicle's operator to remain in a comfortable environment while the ROV performs the work underwater. An umbilical, or tether, carries power and command and control signals to the vehicle and the status and sensory data back to the operators topside. In larger systems, a subsea garage and tether management system (TMS) are often included.

ROV classification 1/3 ROVs can vary in size from small vehicles fitted with one TV camera (used for simple observation in shallow water), up to complex work systems that can have several manipulators, video cameras, mechanical tools and other equipment. They are generally free flying, but some are bottom-founded on tracks Towed bodies, such as those used to deploy side scan sonar, are not considered ROVs

ROV classification 2/3 HIGH CAPABILITY ELECTRIC (GENERAL CLASS) ROV electrically operated much smaller in size than Work Class Rovs suitable for observation and light work Electric vehicles have gained popularity with the military and science markets due primarily to their quiet operation. In addition, the work requirements for military and science are, in most cases, not as complex when compared to ROVs used for oil and gas operations. WORK CLASS very large in size and operated by a crew (supervisor, pilot and in some instances a co-pilot) electro-hydraulic (>100 hp power) used for a wide range of work, repair jobs and recovery of large objects These ROVs range in weight from 2,205-4,410 lbs (1,000-2,200 kg) with typical payload capacities in the lb ( kg) range Typical tasks for this class are drilling support (where most are deployed), light construction support, pipeline inspection and general "call out" work. HEAVY WORK CLASS ROV This represents the class of ROVs being used for current deepwater operations to 10,000 feet (3,000 meters) ranging from horsepower and having through-frame lift capabilities to 11,025 lbs (5,000 kg).

ROV classification 3/3

PEGASO PROJECT ERDF: European Regional Development Fund

The PEGASO Project borns from the Lesson Learned of NEMO sea operations Commercial ROV for deep sea applications (>2000m), on-board of the ship, usually are too huge for scientific purpose; High cost for rent ship and ROV; Few deep sea ROV on the market for scientific application; Difficult to schedule time ship and ROV Standardization of structure, geometry, way of connection, …. it’s a must for an optimization of time, safety and cost for sea operations WHY?

A Special System PEGASO is a project over the period aimed at enhancing the NEMO SN1 infrastructure. It is funded by the Regional Authority (Regione Siciliana) within European Structural Funds and co-financed by INGV and INFN which are also the partners of the project. The main goal of PEGASO is the development of a deep-sea modular handling facility able to service underwater infrastructures down to 4000 m w.d. PEGASO handling facility will include two main subsystems: the Deep Sea Shuttle (DSS); a Customized model of a deep-sea ROV (C-ROV). The DSS will be designed and built to work both as a lifter of heavy scientific payloads and as a active driving interface of the C-ROV.

Goal of the PEGASO project deployment and recovery of heavy complex structures (km 3 detection units, GEOSTAR-like observatories, multi purpose JBs, deep-sea scientific stations, etc.); plug and unplug of ROV wet mateable connectors; visual inspections and maintenance operations on existing infrastructures; multi purpose scientific operations (e.g. survey of bioconstructions, samplings).

Recovery and deployment Configuration PEGASO Project

Connection and disconnection configuration PEGASO Project

depth rating: 4000 m. typical operations: handling of wet mateable connectors (ODI, SEACON, …), handling of deployment tool (reel, acoustic beacon, ecc.), use of cables cutter on board instrumentation:  5 video channel;  sonar;  pressure sensor (precision 1:1000);  Tether management system, hosting 200m of cable; max speed: 3 node; dimension and weight: 0.80 (h) x 1.5 (l) x 1 (w) m, weight in air 400 kg. Main ROV Characteristics

Time Schedule ROV DSS Integration Sea trials Jan ‘08 Jun ‘08 Dic ‘08

INFN ROV inside TMS cage

2 x 5 functions manipulator’ skid

three free outlet for customized 3 axis “connector plug tool”

customized 3 axis “connector plug tool”

the Deep Sea Shuttle

Conclusions In order to install a deep sea neutrino telescope, the use of an ROV is strongly recomended; Following the experience given by the NEMO phase 1 structures, INFN wrote down some specifications for a project of two deep sea infrastructures (ROV and DSS); The project has been financed by the Sicilian Region; At the moment the project is going to be completed and INFN will have two important tools to deploy a neutrino telescope.