Slocum Underwater Glider
Slocum glider is a long-endurance autonomous underwater vehicle designed and manufactured by Teledyne Webb Research.
The buoyancy-driven underwater glider supports long-range operations and long-endurance remote water column observations.
The underwater glider can be integrated with custom sensors and can be used to demonstrate multiple ocean basin crossings.
https://www.naval-technology.com/projects/slocum-underwater-glider/