Underwater

Marine aquaculture pens have to be regularly checked for holes, plus the fish need to be inspected for parasites. And although the job is typically performed by human divers, it turns out that a robotic sea turtle may be a better choice for the task.

Although autonomous underwater vehicles (AUVs) are electrically-powered, they're launched from fuel-burning surface vessels. A new, more environmentally-friendly system is being designed to replace those ships with wave-powered underwater AUV stations.

The annual Ocean Art Underwater Photo competition, now in its eighth year, is a chance to get up close and personal with our marine cousins so many times removed. Here are all this year's winners and runners up in a spectacular photo gallery.

Although many scuba divers utilize wearable computers to track dive stats, those devices can't record an actual map of the underwater route that the user travelled. The newly-developed Brizo, however, is claimed to do exactly that.

Surface-supplied diving systems find balance between snorkelling and scuba by strapping you to an air supply floating atop the water. Typically these systems rely on compressed air, but the ExoLung uses a more sustainable air supply: you.

Given how 360-degree video cameras allow viewers to feel as if they're "in" the viewing environment, it would follow that one of their best uses would be for shooting underwater footage. Well, the 360bubble Deep is designed to help that happen.

The Nautismart Pro housing reportedly allows almost any phone to take photos underwater.

A new MIT system is designed for charging batteries to power a network of sensors that would transmit data from the sea floor.

​Let's face it: due to the amount of thrust required to lift a person off the ground, practical personal jetpacks may never exist – at least, not for use in the air. Underwater jetpacks, however, are another story. We've seen a few lately, with one of the latest incorporating a novel backpack unit.

​Fans of the movie Prometheus will recall the probes that were sent into the alien structure, autonomously flying through it to create a 3D map of its interior. Well, something kind of similar is now in development, in the form of an underwater robot that maps the flooded tunnels of abandoned mines.

Ten years ago, François-Alexandre Bertrand had an idea for a novel watercraft that cruised to a site and then lowered its passengers below the water to have a look around. Now the first Platypus Blue Ocean has been sold, and the order books officially opened.

​You know those cool photos that are half-above the surface of the water, and half-below it? They're called split shots, and a new underwater housing is designed to let you take them using a wide variety of smartphones.