Featured Research

from universities, journals, and other organizations

Jellyfish inspires latest ocean-powered robot

Date:
March 21, 2012
Source:
Institute of Physics (IOP)
Summary:
Researchers have created a robotic jellyfish, named Robojelly, which not only exhibits characteristics ideal to use in underwater search and rescue operations, but could, theoretically at least, never run out of energy thanks to it being fueled by hydrogen. Constructed from a set of smart materials, which have the ability to change shape or size as a result of a stimulus, and carbon nanotubes, Robojelly is able to mimic the natural movements of a jellyfish when placed in a water tank and is powered by chemical reactions taking place on its surface.

Robojelly.
Credit: IOP

American researchers have created a robotic jellyfish, named Robojelly, which not only exhibits characteristics ideal to use in underwater search and rescue operations, but could, theoretically at least, never run out of energy thanks to it being fuelled by hydrogen.

Constructed from a set of smart materials, which have the ability to change shape or size as a result of a stimulus, and carbon nanotubes, Robojelly is able to mimic the natural movements of a jellyfish when placed in a water tank and is powered by chemical reactions taking place on its surface.

"To our knowledge, this is the first successful powering of an underwater robot using external hydrogen as a fuel source," said lead author of the study Yonas Tadesse.

The creators of Robojelly, from Virgina Tech, presented their results 21 March, in IOP Publishing's journal Smart Materials and Structures.

The jellyfish is an ideal invertebrate to base the vehicle on due to its simple swimming action: it has two prominent mechanisms known as "rowing" and "jetting."

A jellyfish's movement is down to circular muscles located on the inside of the bell -- the main part of the body shaped like the top of an umbrella. As the muscles contract, the bell closes in on itself and ejects water to propel the jellyfish forward. After contracting, the bell relaxes and regains its original shape.

This was replicated in the vehicle using commercially-available shape memory alloys (SMA) -- smart materials that "remember" their original shape -- wrapped in carbon nanotubes and coated with a platinum black powder.

The robot is powered by heat-producing chemical reactions between the oxygen and hydrogen in water and the platinum on its surface. The heat given off by these reactions is transferred to the artificial muscles of the robot, causing them to transform into different shapes.

This green, renewable element means Robojelly can regenerate fuel from its natural surroundings and therefore doesn't require an external power source or the constant replacement of batteries.

At the moment, the hydrogen-powered Robojelly has been functioning whilst being clamped down in a water tank. The researchers admit that the robot still needs development to achieve full functionality and efficiency; however, the potential can be seen in this video (http://www.youtube.com/watch?v=U2OSJQhHQp8) where the robot is powered by electricity.

"The current design allows the jellyfish to flex its eight bell segments, each operated by a fuel-powered SMA module.. This should be sufficient for the jellyfish to lift itself up if all the bell segments are actuated.

"We are now researching new ways to deliver the fuel into each segment so that each one can be controlled individually. This should allow the robot to be controlled and moved in different directions," Tadesse continued.

This study is part of the MURI program sponsored by Office of Naval Research.


Story Source:

The above story is based on materials provided by Institute of Physics (IOP). Note: Materials may be edited for content and length.


Journal Reference:

  1. Yonas Tadesse et al. Hydrogen-fuel-powered bell segments of biomimetic jellyfish. Smart Materials and Structures, 2012; Volume 21 Number 4 DOI: 10.1088/0964-1726/21/4/045013

Cite This Page:

Institute of Physics (IOP). "Jellyfish inspires latest ocean-powered robot." ScienceDaily. ScienceDaily, 21 March 2012. <www.sciencedaily.com/releases/2012/03/120321094133.htm>.
Institute of Physics (IOP). (2012, March 21). Jellyfish inspires latest ocean-powered robot. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2012/03/120321094133.htm
Institute of Physics (IOP). "Jellyfish inspires latest ocean-powered robot." ScienceDaily. www.sciencedaily.com/releases/2012/03/120321094133.htm (accessed July 31, 2014).

Share This




More Matter & Energy News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Britain Testing Driverless Cars on Roadways

Britain Testing Driverless Cars on Roadways

AP (July 30, 2014) — British officials said on Wednesday that driverless cars will be tested on roads in as many as three cities in a trial program set to begin in January. Officials said the tests will last up to three years. (July 30) Video provided by AP
Powered by NewsLook.com
Amid Drought, UCLA Sees Only Water

Amid Drought, UCLA Sees Only Water

AP (July 30, 2014) — A ruptured 93-year-old water main left the UCLA campus awash in 8 million gallons of water in the middle of California's worst drought in decades. (July 30) Video provided by AP
Powered by NewsLook.com
Smartphone Powered Paper Plane Debuts at Airshow

Smartphone Powered Paper Plane Debuts at Airshow

AP (July 30, 2014) — Smartphone powered paper airplane that was popular on crowdfunding website KickStarter makes its debut at Wisconsin airshow (July 30) Video provided by AP
Powered by NewsLook.com
U.K. To Allow Driverless Cars On Public Roads

U.K. To Allow Driverless Cars On Public Roads

Newsy (July 30, 2014) — Driverless cars could soon become a staple on U.K. city streets, as they're set to be introduced to a few cities in 2015. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



    Save/Print:
    Share:  

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile iPhone Android Web
    Follow Facebook Twitter Google+
    Subscribe RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins