A start-up company in the US has patented a new technique that can create authentic hinges in carbon fiber reinforced plastic with very little reduction in strength and a big increase in flexibility. The technology has the potential to be used in everything from airplanes to wallets, says Liz Nickels.

Three years ago, on a drive from Seattle to San Luis Obispo in California, Ann Livingston-Peters and Gabriel Mountjoy had an idea about to how to make carbon fiber more functional: by creating hinges within the material itself. It took another year to actually determine how to create such a hinge. After trying many methods, the two students discovered that the most effective way to create a hinge in carbon fiber was to use a laser.

While still at California Polytechnic State University, the team competed on the Cal Poly Supermileage Team, a project dedicated to designing, engineering, and manufacturing high efficiency vehicles. One of the most important design considerations in this case was weight, since a 1% reduction in vehicle weight can result in a 0.7% increase in fuel economy. In order to minimize weight, a monocoque chassis design with integrated composite doors was proposed. A total of four composite hinges, each about ½ m long, were used in creating the main driver access doors and the rear engine compartment, reducing the overall weight of the car to 35 kgs. The team ended up placing 7th.

The technology went on to be awarded the Technical Innovation Award at the 2013 Shell Eco-Marathon Americas for the use of the integrated hinges. The Shell Eco-Marathon challenges student teams from around the world to design, build, and test ultra-energy efficient vehicles. With annual events first in the Americas, then Europe and Asia, the winners are the teams that go the furthest using the least amount of energy. This first recognition of the technology made the team realize they needed to push further.

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