The PoNA USV represents the first Unmanned Surface Vehicle built for the Portuguese Navy in collaboration with Arsenal do Alfeite, S.A. and CINAV (the Portuguese Navy's naval research centre). This vessel reflects the current decade's newfound interest and investment in the development of unmanned platforms for military applications by NATO's Armed Forces.
Featuring a catamaran hull shape and a versatile modular central platform, this 3.4 meter long vessel is designed to be employed in a wide array of missions and scenarios by the Portuguese Navy. It's innovative modular structure allows custom payloads up to 140kg to be easily exchanged in the field allowing the USV to be employed in different tasks accordingly. The following paper describes the entirety of the design development process for the USV, from concept development to the detailed design according to MCA standards for multi-hull vessels, as well as the ensuing construction and sea trials of the USV, integrating both composite materials and aluminium in its construction. All the design and manufacture challenges faced through this process are also detailed in the paper. From the development of spreadsheets for initial sizing, power predictions and hull resistance, the use of CAE software for design, hydrostatic and stability analysis, loading condition calculations and finite element analysis purposes. Resistance tests in the Portuguese Naval Academy's Ship Model Tank are also expanded upon in the paper, along with the design and construction of a simple sensor for the model resistance tests. The use of 3D printing for rapid prototyping is also addressed in this work. The PoNA USV is currently under design development in the Portuguese Naval Academy and is due to enter service in the summer of 2020.