Carbon nanotubes are a ground-breaking material that have been proposed for use in everything from solar paint to the construction of space elevators. Now the University of Texas in Dallas has announced that they plan to use the nanotubes to create artificial muscles that can lift more than 100,000 times their own weight and generate 85 times more mechanical power than natural muscle of the same size.
The Texan team constructed a muscle made from yarns of carbon nanotubes. The yarns are seamless, hollow cylinders, that are made from the same type of graphite layers found in the core of ordinary pencils. These yarns were then infiltrated with paraffin wax and twisted until coils formed along their length. The team then heated the yarn using electricity or heat, causing the wax to expand and the yarn volume to increase. This in turn caused the yarn length to contract – just like a real muscle.
In a press release, team leader Ray Baughman said: “The artificial muscles that we’ve developed can provide large, ultrafast contractions to lift weights that are 200 times heavier than possible for a natural muscle of the same size. While we are excited about near-term applications possibilities, these artificial muscles are presently unsuitable for directly replacing muscles in the human body.”
“Because of their simplicity and high performance, these yarn muscles could be used for such diverse applications as robots, catheters for minimally invasive surgery, micromotors, mixers for microfluidic circuits, tuneable optical systems, microvalves, positioners and even toys.”
Baughman added that because the yarn muscles can be twisted together and are able to be woven, sewn, braided and knotted, they might eventually be deployed in a variety of self powered intelligent materials and textiles.
While the new technology has many applications, it is not expected to be used in human surgery in the near future, however it could be used in robotics. The team is currently working to upscale the single yarn muscles to larger and more complex systems which would implement thousands of yarn muscles in parallel – just think of the amount of weight that this could lift?