Rex II is a remote controlled, unmanned submarine. It moves about underwater, suspended by a tether that connects to a floating cylinder at the surface. By extending above the surface, a high-bandwidth connection between the operator and the vehicle is possible using radios. Also, a GPS on the float provides accurate navigation. (Radio and GPS signals will not travel through water.) The operator watches the live video feed from the vehicle, and controls it with a video game controller.
The vehicle was constructed for my Master's thesis in the Mechanical Engineering Department at MIT.
Much more technical information is available in the thesis.
Download: Rex II Thesis, 3.0 MB
Dozens of hours of onboard video and externally shot footage was compiled into a 20 minute demonstration video. The ocean footage is from various locations on Oahu, Hawaii. On slow connections, pause after playing to allow buffer to fill.