As uncertainty about the future of fossil fuels grows, so does the interest in alternative energy sources. In an effort to tap the limitless energy of the ocean’s waves, engineers at Tokai University developed an engineless, wave-powered boat propulsion system for the Suntory Mermaid II, a 3-ton catamaran piloted by 69-year-old Japanese sailor Kenichi Horie on a voyage from Hawaii to Japan.

In early July, the Suntory Mermaid II completed the 7,800-kilometer journey from Hawaii to Japan, setting the Guinness world record for the longest distance ever traveled by a wave-powered boat.

The propulsion system uses two spring-powered fins beneath the bow that move up and down with each incoming wave, generating dolphin-like kicks that pull the boat forward. Traveling at an average speed of 1.5 knots, the Suntory Mermaid II took a little over 3 months to complete the voyage -- much longer than an ordinary diesel-powered vessel would take. But while the Suntory Mermaid II did not break any speed records, the groundbreaking voyage successfully demonstrated the wave propulsion system’s ability to work in real-world conditions.

According to the developers, wave-powered propulsion systems like these could one day help maritime shippers cut fuel costs. And because waves are everywhere, energy will never be in short supply.

Links:
Suntory Mermaid II
Sailor ends 4,800-mile wave-powered journey [MSNBC]
Long Ocean Voyage Set for Vessel That Runs on Wave Power [New York Times]
Wave Runner [Popular Science]

Kenichi Horie, solo sailor of the wave-powered Suntory Mermaid II, is seen on deck as he departs Honolulu on March 16, 2008 on his record-breaking voyage.
(Photo by Shigeo Yamada)


Kenichi Horie reached Nishinomiya port
on July 6, 2008.

Aerospace scientists have teamed up with origami experts in a project to fly paper airplanes from the International Space Station to Earth. Led by University of Tokyo aerospace engineer Shinji Suzuki, the project could pave the way for designing lightweight re-entry vehicles and space probes that explore the upper atmosphere.

In February, the researchers tested a miniature version of the origami plane in a hypersonic wind tunnel. The 7 x 5 centimeter prototype, made from paper that is chemically processed to incorporate silicon into its structure, survived the Mach 7 wind speeds and 230 degree Celsius aerodynamic heat that an origami shuttle might experience during re-entry. Following the successful tests, the Japan Aerospace Exploration Agency (JAXA) adopted the project for feasibility studies. If all goes well, astronaut Koichi Wakata – who has taken a personal interest in the project – will throw the paper airplanes toward Earth from the space station on a future mission.

At this point, it is unclear whether or not paper airplanes thrown from the space station would actually return to Earth, and there is no way to track their flights or know where they will land. According to Suzuki, however, there is much to be learned simply by trying.

Links:
Scientists, origami masters float paper plane re-entry [The Japan Times]
The Ultimate Paper Airplane [Air & Space/Smithsonian]
'Mach 20' paper airplane could launch from Space Station [Discovery Channel]

The 7-cm long, 5-cm wide origami shuttle is pictured before the hypersonic wind tunnel test.


Testing the origami shuttle in a hypersonic wind tunnel.
(Provided by Prof. Shinji Suzuki)

An LCE belt measuring 0.08 mm in thickness was looped around a pair of wheels measuring 10 mm and 3 mm in diameter. When UV light was focused on the belt near the smaller wheel and visible light near the larger wheel, the belt rotated at a speed of approximately 1 rpm. (Provided Dr. Tomiki Ikeda)