The Project

The development of the project

Underwater work plays a fundamental role in the sustainability of the world economy. The sea, in fact, in addition to being the scenario in which a large part of the extraction of fossil fuels takes place, is a candidate to become, in perspective, the source of much of the renewable energy produced on the planet. In addition to the sea-energy correlation, there is a sea-exploitation correlation of abiotic resources from the seabed (for example minerals) that will become increasingly important in the coming decades.
Robots are involved in underwater work and, limited to a depth of 300 meters, also human operators with appropriate certified training; in other words Certified Commercial Divers – CCD. The involvement of human beings requires a significant increase in safety, while at the same time safeguarding the effectiveness, improving the efficiency and the quality of life for all those involved, including surface operators.

Underwater intervention operations and close inspection of structures, such as welding of pipes, laying cables, assembling and/or disassembling structures, recovery of objects/finds, etc., are typically carried out, based on the danger, depth and type of operation to be performed, by CCD and/or by Remotely Operated Vehicles (ROVs), robots remotely controlled by pilots who are on the surface. The use of autonomous vehicles or AUVs (Autonomous Underwater Vehicles), for intervention and close inspection operations is still relegated to research laboratories.

The use of CCD and ROVs is not mutually exclusive: an observation ROV is always used to monitor the CCD during the working phases, sending the images to the mission supervisor in the control room located on the surface. In addition, CCD and ROVs can alternate in the execution of certain operations depending on the dexterity or strength required, favouring CCD for greater dexterity and ROV interventions for strength.

The CCD: heroes unknown to most

CCD breathe mixtures of helium and oxygen and remain at high pressure (saturation) for periods of 4 weeks. This activity involves the use of:
– bells for transporting the CCD from the support vessel/platform to the depth of the works and vice versa;
– surface hyperbaric chambers (saturation systems) placed on the surface for rest periods and for the pressurization and decompression phases to be carried out at the beginning and at the end of the period;
– pressurized rescue systems (Hyperbaric Evacuation Systems – HES), in the event of a serious failure of the support vessel/platform.
The CCD are subjected to heavy working conditions: 1) environmental temperatures often not higher than 5° C; 2) working shifts of 8 hours in depth; 3) stay of the CCD for the remaining 16 hours in the pressurized environment of surface hyperbaric chambers which are very confined environments, comparable to space stations.

Furthermore, due to the high thermal conductivity of the helium mixtures, the CCD are subject to suffer sensations of suffocating heat or intense cold if an accurate control of the environmental conditions is not foreseen and this requires the creation of technologically advanced hyperbaric chambers to maximize the safety and quality of life.

The SUONO Project

The SUONO project addresses the problems of CCD work safety and the development of an HUV (Hybrid Underwater Vehicle), in other words a vehicle capable of operating both under the guidance of a pilot and autonomously, to cover the entire operational chain of Commercial Diving. The SUONO project is therefore divided into two sub-projects.


SUB-PROJECT 1 - SAT-Diving System

It involves the development of a Modular Hyperbaric System – MHS (SAT-Diving System) of communicating hyperbaric chambers, including a diving bell and its launch and recovery system, and a module (Hyperbaric Evacuation System – HES) to evacuate the CCD in the event of a support vessel/platform accident. The MHS will also be equipped with devices for the telemonitoring of biomedical data of the CCD, with the possibility of having both medical and specialist psychological teleconsultation. It should be emphasized that CCD in a hyperbaric environment cannot be evacuated by traditional lifeboats and in the absence of a hyperbaric evacuation system, the CCD would have no possibility of rescue. The HES consists of an autonomous self-propelled hyperbaric lifeboat (A-SPHL), its launch system and an emergency module (Life Support Package – LSP) able to allow the decompression of the operators in safe conditions once the aforementioned unit has been recovered from the sea and placed in a protected and safe location (previously identified).

SUB-PROJECT 2 - Hybrid Underwater Vehicle

It involves the development of an HUV, therefore a vehicle with autonomous intervention capabilities, and an Immersive Control Station equipped with virtual and augmented reality technologies and advanced human-machine interaction interfaces for remote control. The manipulation system will allow manipolation operations in both remote controlled and semi-autonomous mode on a defined set of actions. The semi-autonomous manipolation mode will significantly reduce the stress and the possibility of human errors by the operator, thus increasing their quality of work life.
The Immersive Control Station will allow driving and manipolation operations in an intuitive and efficient way. The station will operate in synergy with a vision and visual-servoing system on board the HUV and will be equipped with: (1) an immersive vision system that will increase the operator’s telepresence level and (2) a driving interface. based on advanced human-machine interaction systems.



The result of the project, beyond that produced in terms of instrumentation and operational models dedicated to underwater work, is the implementation of an integrated system that is safe for extreme environments, which in itself constitutes a unique achievement. In this regard, what differentiates the SUONO project from other projects is precisely the study of human-environment interaction and the human response to extreme conditions, also from the point of view of the social structure in which individuals are forced to live for long periods.
This component places the project in the context of a new “technological humanism” in which the contribution of apparently unrelated partners is summarized in the creation of a project which has at its centre man and his quality of life, understood mainly as a harmonic integration with the physical, architectural and social environment.
On this basis, the philosophy of the project can become a technological/scientific/social reference for all operators in a hostile environment (for example, firefighters, civil protection, military, etc.) who will be able to benefit from real innovative know-how, where man’s safety and health are at the centre of industrial development and basic research.
The natural evolution of the SUONO project will therefore be the extension of ​​the methods and systems created with reference to the underwater environment to the “terrestrial” area, once again with the ultimate goal of improving safety at work, optimizing work performance through robotic technologies and identifying preventive strategies aimed at maintaining well-being.


Benedetto Allotta – University of Florence – DIEF

The SUONO Project is funded by the Italian Ministry of Education, University, and Research in the framework of the call on Smart Cities and Communities - Topic on Marine Technologies (2014 - 2021)

With the participation of the Ministry of the Environment and the Tuscany Region