Fabrication of meso-scale underwater vehicle components by rapid prototyping process

Underwater vehicles have been developed in many ocean exploration and rescue applications. In smaller scale of underwater vehicles, critical components are not usually commercially available. The cost of non-standard parts is relatively high in the development stage if special molding or precision machining is involved. In this research, major components, propellers and the hull structure, for a meso-scale underwater vehicle were needed in the prototyping stage. Rapid prototyping process was targeted for this purpose. Due to the 3D profile and resolution requirements, shape deposition manufacturing (SDM) process was selected to fabricate these polymer components. Without special fixtures or molds, propellers with smooth surfaces were successfully manufactured by the SDM process. Besides, two types of assembly strategies of the hull structure were investigated. Type I involves dividing the hull vertically and screwing the two halves together, while Type II separates the hull horizontally and seals by glue after assembly. The parts of the hull for these two approaches were both achievable by the SDM process and Type II was favored in terms of time consumption. In conclusion, this research has provided a solution to fabricate 3D complex components of the meso-scale underwater vehicles prototypes and can be extended to other similar-scale vehicles.