Robots running on batteries and electricity are old news now as researchers have recently created worm-shaped robots that can run on moisture only.

Researchers from the Seoul National University have invented robots that can ‘inchworm’ forward by absorbing humidity from their surroundings. Named ‘Hygrobots’, the robots can crawl, twist back and forth and also like a snake.

The researchers were inspired from plants to create these robots. Plants can change shape and their size through absorption of water from the air or from the ground, a process known as hygroexpansion. However, these are not made from plant material, they just replicate the functioning of them, reported The Verge.

Watch this humanoid robot work out and sweat

These types of robots are also more convenient as compared to the normal robots that are made from batteries. Moisture is a natural source in environment and is not even toxic, whereas, batteries are toxic and can also explode. What’s more interesting about these robots are that they can be easily used inside human body.

The hygrobot is made up of two layers of nanofibers, one that absorbs moisture and one that doesn’t. When on wet surface, the moisture absorbing layers swells up that moves the robot up, while the other layer stays the same, when it has been dried down, the robot goes down. This cycle keeps on repeating because of which the bot moves.

According to Engadget, as a part of demonstration, one of the hygrobots was loaded with antibiotic and had to move across a petri dish containing bacteria. When it was done, the strip along the robot’s path was entirely bacteria free. For the future, researchers believe that these tiny robots can be useful for military, industrial, and medical purposes. Described in the journal Science Robots, the robots can be used to delivering drugs into human skin functioning on skin moisture only.