Wire Bike uses carbon fiber and Kevlar cables
By Paul Evans
March 9, 2009
March 9, 2009 Super light structural materials such as carbon fiber and Kevlar have incredible natural strength in tension but are much weaker in compression. A good example of this is how the carbon fiber suspension on a formula one car can resist several tons of downforce but explodes when crashed into a barrier. The concept of tension has been a familiar sight in large engineered structures such as suspension bridges and now the same concept has been applied to a bike frame.
We have seen the down tube on a bike frame replaced by a steel cable in the Slingshot bike, now Romanian industrial designer Ionut Predescu has come up with a concept bike frame that uses just two carbon fiber tubes and takes advantage of the tensile strength of Kevlar wire to replace all other tubes usually found in a bike frame. He calls it a Tensegrity frame, a term invented by Buckminster Fuller of Geodesic dome fame which is a portmanteau of Tensional Integrity.
The idea is similar in concept to the spokes in a wheel where it’s actually tension on the spokes that holds the wheel together, not compression. The result is a super light, high strength frame where "elements seem to float one against the other", although as the designer himself admits, there may be issues with lateral stability. A prototype will tell the tale - we'd love to see one.
Source: ionut predescu (Coroflot).