An amazing nano-scale microscopic muscle with more than 1000x the strength of humans was reportedly created by the U.S. Department of Energy's (DOE) Lawrence Berkeley National Laboratory (LBL) researchers using the vanadium dioxide inorganic compound.
The research team is composed of Junqiao Wu, Leon O. Chua, Kai Liu, Joonki Suh, Deyi Fu, Sangwook Lee, Chun Cheng, Robert Tang-Kong and Jian Zhou. The team's research paper titled "Powerful, Multifunctional Torsional Micromuscles Activated by Phase Transition," was published in the journal Advanced Materials on Dec. 19, 2013.
According to the Berkeley Lab News Center, Junqiao Wu's team of researchers from their laboratory was able to create a powerful new microscale robotic torsional muscle or motor from vanadium dioxide. It can catapult objects which are 50 times heavier than its size within 60 milliseconds. It can also throw heavy objects over a distance that is five times its length.
"We've created a micro-bimorph dual coil that functions as a powerful torsional muscle, driven thermally or electro-thermally by the phase transition of vanadium dioxide," said research leader and physicist Junqiao Wu from the University of California-Berkeley's Department of Materials Science and Engineering and Berkeley Lab's Materials Sciences Division in the Berkeley Lab News Center report.
"Using a simple design and inorganic materials, we achieve superior performance in power density and speed over the motors and actuators now used in integrated micro-systems," Wu added.
Vanadium(IV) dioxide (VO2) is a dark blue solid inorganic compound that is considered to be amphoteric. This means that it can react as a base and as an acid. It is a very interesting compound because of its unique thermoelectric properties. It can be an insulator and a conductor depending on the temperature. When exposed to temperatures of above 68 degrees Celsius, the structure of vanadium dioxide changes. Its magnetic susceptibility as well as its electrical conductivity increases.
Wu and his team used a long "V-shaped" bimorph ribbon that is made up of vanadium dioxide and chromium. They used a silicon substrate to fabricate the micro-muscle. It has a dual coil that turns into a mini catapult when heated. It can also sense a nearby object and once it does, it pushes it away. The Berkeley Lab researchers also found that the vanadium dioxide microscopic muscle is extremely resilient. They tested it and discovered that even if the muscle has been rotated more than one million times at up to 200,000 rpm, it didn't lose its function and continued to perform well.
This nano-scale microscopic muscle with more than 1000x human strength that was created by Berkeley researchers using vanadium dioxide is truly a breakthrough because despite its small size, it is very powerful and functional.