Deliverable ISSIA 1.1 RITMARE

This work describes the design of a new propulsion unit for Unmanned underwater vehicles of CNR-ISSIA. The propulsion unit, designed for medium depths down to 500 m, is related to the realization of the new hybrid AUV/ROVs e-URoPe and P2-ROV developed by the same CNR-ISSIA. These Remotely Operated Vehicle is realized using the most innovative technical capabilities in order to achieve a flexible structure, adequate to withstand external impacts. The peculiar characteristics of these vehicles, on which is based the design concept, are: easiness of construction, facility of re-configuration and flexibility. The vehicle can be completely modified in terms of propulsion layout thus requiring a modular unit with enhanced characteristics. The module main characteristics are high reliability, low-weight, low bulkiness, easiness of adaptation to different vehicles and layouts. As mentioned before, e-URoPe and P2-ROV belong to the newest class of underwater vehicles capable of working both in the remotely controlled configuration with a tether cable (ROV) and autonomously without a tether cable (AUV). These vehicles were designed with the idea of machines that could be easily transported and deployed by a small team of scientists. The team should be able to re-configure the vehicle by using simple tools. In this context it is possible to modify the frame and change the propulsion layout. For this reason the vehicle maximum depth was limited to 250 m, a good compromise between the operational needs and the logistics requirements. Indeed a vehicle for higher depths would require a stronger structure, with significant increase in weight, dimensions, buoy (and its weight), cable length and, thus, winch weight. Keeping all this in mind, the operations in the more risky environmental areas could be performed by using a reduced logistics. The vehicles are designed to be predominately remotely operated and video controlled via a high bandwidth fiber-optic cable, but for wider operations it's provided the possibility of autonomous operations. The main purposes of these vehicles will be the support in scientific missions for the most different applications dealing with man-machine cooperation like sampling of water or objects, video support, underwater manipulation, mapping of seabed and detection of underwater vegetation, archaeological surveys, sampling under ice in the polar regions.