Euro 2008 Complaint: The Perfect Ball with the Imperfect Wobble
The ultra-modern high-speed ball being used in the Euro 2008 has been slammed by goalkeepers who complain it wobbles too much. The designer of the latest version, the Europass, thinks it's all just a question of how you see things.
German midfielder Tim Borowski plays with the ball during a training session. Goalkeepers have complained that it flies too wobbly.
For the past 12 years Nürnberg, 44, an athletic-looking man in jeans, has been developing footballs for the sporting goods company Adidas, which always provides the equipment for the tournaments. As part of the company's innovation team, he helped create the "Fevernova" for the 2002 World Cup, and he is particularly proud of the current model, the "Europass." But then this happens. Nürnberg leans forward in his chair, which looks like the hollowed-out stud of a football shoe, and says: "It doesn't leave you cold."
He has come to Vienna for two days, to the company's EURO 2008 headquarters in a building in the city's museum district. On the lot in front of the building, giant replicas of the stars' shoes are on display, but what everyone is talking about this year is the ball. It wobbles, said German defender Philipp Lahm, and it suddenly looked as if one side had drastically miscalculated over what has become a sport dominated by the materials used.
But what if the ball wobbles all the same? According to Nürnberg, it's a "phenomenon that has been blown out of proportion." A design engineer, who once played on FC Cologne's C youth team, he also developed testing procedures for the balls. The Europass was tested in a wind tunnel, a radar device known as a "Track Man," once used by the military to detect projectiles, measured its trajectory and its water absorption was measured in a water bath.
The goal was to develop a homogeneous ball that was as impervious to adverse weather conditions as possible. A robot leg, which the researchers dubbed "Robby Leg," repeatedly drives the ball, at speeds of 100 kilometers an hour (62 mph), against almost the exact same spot in the corner of the goal. Even when the ball is sprayed with water, it deviates from its target by no more than half of its diameter.
Nürnberg is growing tired of goalkeepers' complaints. "We don't want to prevent them from catching the ball," he says. Goalkeepers have long seen themselves as the victims of progress. Since 1992, they are no longer permitted to handle the ball after a back pass and in the modern defensive game they have to serve as a sweeper, which can sometimes be dangerous. For example, Cech has been wearing a carbon helmet since fracturing his skull last year after colliding with a fellow player.
Hans-Peter Nürnberg with his World Cup 2006 ball "Teamgeist."
It is as if an arms race had sprouted up between the forward and the man in the goal. Nowadays, goalkeepers prefer to punch rather than catch the modern, high-speed ball. The Adidas glove now includes the "Punching Power" system -- small knuckle pads made of plastic and air cushions.
But none of this does any good against a wobbling ball. Every flying ball is exposed to air currents, and lateral forces can even propel a spinning ball around a corner. This is called the Magnus effect or a banana kick. Unlike footballers, volleyball players take advantage of the phenomenon in which a ball flying without spin begins to wobble and suddenly plunges to the ground. This is caused by dramatically increasing air resistance and turbulence forming in the wake behind the ball.
Does the Europass create an especially large amount of turbulence in flight? Perhaps, says biomechanics expert Wolfgang Potthast. His institute at the German Sport University in Cologne tested Europass' predecessor "Teamgeist" for FIFA. The new ball, says Potthast, which is as perfectly round as they come, may be easier to kick in such a way that it doesn't rotate -- a precondition for the wobble effect. In that case, the wobbling in mid-flight would actually be a result of the ball's perfection.
Nürnberg, the ball's creator, doesn't believe that this is true. After all, he says there have been many perfect catches of the ball during EURO 2008, even at the end of longer, tightly played passes. Instead, Nürnberg believes that the problem is a visual one. The design includes all kinds of symbols, logos and the national flags of the teams. Lehmann and Cech, who were unfamiliar with the ball from the English league, may have simply been irritated.
This may be taken into account in future models, says Nürnberg. He has already finished the ball for the 2010 World Cup.
Translated from the German by Christopher Sultan
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