The MIT Sea Grant will develop a new version of the Reef Explorer (ReX) an inexpensive, robust and maneuverable hybrid vehicle, part autonomous (AUV) and part remotely operated (ROV.) ReX III/IV will use an unmanned surface craft with a radio modem to communicate to shore locations over the web. ReX III/IV has onboard power, computers, and intelligence. It will supply high-bandwidth communication through the use of an onboard winch and vertical tether linked to the modem aboard the surface vehicle. The objective is to install the tele-operated underwater vehicle system at the Hawaii Institute of Marine Biology to support research and provide educational opportunities to study the diverse habitat of Kaneíohe Bay from remote locations.