Vibration-cancelling composite technology a boon for bicyclists

The Infinito CV was ridden by cyclist Lars Boom to victory in Stage 5 of the 2014 Tour de France, a segment known for its teeth-chattering cobblestones.

Bicycle manufacturer Bianchi (Milan, Italy) was recently recognized for its updated Infinito CV carbon composite model, named “Bike of the Year” by bicycling Web site www.road.cc. The Infinito CV was ridden by cyclist Lars Boom to victory in Stage 5 of the 2014 Tour de France, a segment known for its teeth-chattering cobblestones.

A key element of the Infinito model is an integrated vibration-cancelling product called COUNTERVAIL (a globally registered trademark) developed and produced by Materials Sciences Corp. (Horsham, Pa.). The latter has provided design, analysis, engineering and testing services to the advanced composites industry since 1970, and has worked with the U.S. Army, Navy and Air Force. NASA and the Defense Advanced Research Projects Agency (DARPA), as well as notable industry players, such as McDonnell Douglas (now Boeing) Phantom Works.

Materials Sciences’ commercial COUNTERVAIL product combines traditional vibration-damping layer concepts with a patented fiber preform to offer reportedly “unparalleled” vibration reduction in composite structures. The preform’s woven fiber pattern maximizes the vibrational energy dissipation achieved by an integrated viscoelastic damping layer. Damping performance has been shown to be at least 200 percent better than similar constructions using traditional viscoelastic methods. Reportedly, layups can be tailored to balance the vibration-damping coefficient with stiffness and strength, and even drapeability. Very high damping is possible with carbon fiber, and good damping is achievable with glass, at a lower cost. The company says COUNTERVAIL is unique because it is integrated into the structure without adding parasitic weight.

When a bike tire passes over a cobblestone, the initial shock impulse excites the structure and causes it to resonate at certain frequencies. COUNTERVAIL is able to damp that resonance very quickly, and does so much better than rubber damping material employed by other bicycle manufacturers, says Materials Sciences. 

Beyond bicycle frames, COUNTERVAIL technology offers the potential for thinner, lighter aircraft interior panels that offer airlines the benefit of reduced transmission of engine and airflow noise into the aircraft cabin. Similarly it can mitigate repeated and severe shock loads experienced by marine vessels as the result of high-speed wave impacts.