Sentry is an autonomous underwater vehicle (AUV), which means it can operate independently (autonomously) of a human controller. This is especially useful for making long, repetitive or complicated measurements such as mapping large areas of the sea floor. It can be pre-programmed to follow a designated course or carry out a specific task and can also change tasks and directions when it encounters an obstacle or finds something interesting.
Sentry has a streamlined body to reduce drag in the water, help it submerge and surface quickly, and give it stability when maneuvering around obstacles. The vehicle also has four propeller-like thrusters built into its maneuverable foils, or wings, giving Sentry the ability to start, stop, change directions, and ‘fly’ in different ways underwater. It can even hover like an underwater helicopter to do close-up examinations of the seafloor. Sentry is designed to dive as deep as 4,500 meters (3.1 miles) and is powered by more than 1,000 lithium-ion batteries similar to those in laptop computers, which allow it to stay submerged for up to 20 hours.
Click and drag on the Sentry vehicle for a 360 degree view: