‘Semi-sub’ vehicle sails stealthily at water line

According to the researchers, the roughly 450mm long semi-sub prototype, built with off-the-shelf and 3D-printed parts, showed its seaworthiness in water tests, moving quickly with low drag and a low profile. Test results were published in the journal Unmanned Systems.

The team said that while authorities have discovered crudely made semi-subs used for illicit purposes in recent years, this project aims to demonstrate how engineer-developed semi-submersible vessels can serve military, commercial and research purposes.

“A semi-submersible vehicle is relatively inexpensive to build, difficult to detect, and it can go across oceans,” said Konstantin Matveev, the WSU engineering professor leading this work. “It's not so susceptible to waves in comparison to surface ships since most of the body is underwater, so there are some economic advantages as well.”

Since the semi-sub sails mostly at the water line, it does not need to be made of as strong materials as a submarine, which has to withstand the pressure of being underwater for long periods of time. The semi-sub also has the advantage of having a small platform in contact with the atmosphere, making it easier to receive and transmit data, researchers confirmed.