Robot jellyfish, an underwater robot inspired by the animal, can power itself with seawater and could potentially be used for rescue missions, military surveillance and environmental monitoring, according to research published Tuesday.

Engineers designed the robot jellyfish to use oxygen and hydrogen gases from the ocean water as a renewable energy source to power the underwater robot, researchers said.

Though the robot jellyfish is still a long way from completion, the creation could become the newest tool in the suite of underwater robots scientists use to explore the deep ocean.

Engineered jellyfish definitely have a gee-whiz factor, but underwater robots have already found plenty of uses in research, exploration and resource management.

One of the biggest barriers to underwater exploration is pressure - the further underwater you travel, the more pressure water exerts. Robots allow researchers to survey the deep sea without having to risk travelling down themselves.

The Titanic sank 12,500 feet under the ocean after it hit an iceberg in 1912, a depth where the pressure is over 350 times greater than the surface pressure. In 2010, researchers used two autonomous underwater robots to chart the Titanic's wreck site for the first time.

The robots moved along the ocean floor and took 130,000 pictures of the Titanic's final resting place. Researchers stitched the photos together into the first comprehensive map of the Titanic site. The map and other expedition findings will be released on April 15, 100 years after the ship sank.

Underwater visibility frequently impedes research. Robots can pierce through the darkness or murkiness of the ocean to see things human divers simply cannot, making robots invaluable for rescue missions.

After the devastating earthquake that shook Japan in March 2011, Japan and the United States teamed up and used four suitcase-sized robots to inspect bridges and pipelines and to search for bodies. Sediment and debris made visibility nearly impossible, so engineers equipped the robots with sonar. The robots fed video to the controllers so researchers could see what the robot saw in real time.

Rescue workers also used an underwater robot to help find a man missing in Moses Lake, Wash. Deputies from the sheriff's office used a robot to examine a reservoir near where a missing man's truck was found, though to no avail. It was the second time the sheriff's office used the robot.

A few weeks earlier, the department used the robot to investigate a submerged truck. The robot was able to help police determine that the truck was empty without any officers having to venture into the frigid water themselves, according to the Tri-City Herald.

Underwater robots aren't just making discoveries and rescue missions however. They are also being used to get kids and adults more interested in science. The National Underwater Robotics Challenge, held every year since 2007 in Chandler, Ariz., gives kids an opportunity to build a robot of their own to compete in an underwater obstacle course.

The mission of the National Underwater Robotics Challenge is to bring science and technology educational opportunities to the students of all ages across the country, according to the competition website. This event is designed to stimulate the youth of America and to reverse the national 'brain drain.'

Despite the novel technology available and the massive amount of research conducted, much of the ocean is still an enigma.

We have better maps of the surface of Mars and the moon than we do the bottom of the ocean, Gene Feldman, an oceanographer with NASA's Goddard Space Flight Center, said in a 2009 statement. In many ways, it's easier to put a person into space than it is to send a person down to the bottom of the ocean.

However, curiosity, coupled with ever-improving technology, may allow researchers to someday study the hard-to-reach places underwater, he said.