London Calling: The Science of Shuttlecocks

Well, who would have thought Olympic Badminton would get so interesting?

If you're reading this in Ireland, you'll recall the short-lived 'controversy' over the religion of badminton and today we've seen eight female players disqualified over match-fixing scandal. We really should have taken our eyes off the action in the pool and on the beach volleyball arena and kept an eye on the court.

Any badminton I've played myself has been the back-garden or windy-beach variety so I've had the distinct handicap of playing with sub-standard, plastic shuttlecocks (that's the odd device that the players are knocking back and forth). Not good enough to coax out the limited skills even I possess. Perhaps I should have been using the top-of-the-line variety?

The Olympic shuttlecocks are made from 16 goose feathers. Middle of the road shuttlecocks will try and get away with using duck feathers but they generally dry out and crack much more quickly.

According to the laws of the game, controlled by the Badminton World Federation (BWF), the shuttle can be of natural and/or synthetic materials as long as their "flight characteristics generally shall be similar to those produced by a natural feathered shuttle with a cork base covered by a thin layer of leather". Amongst the guidelines are that the feathers should be of uniform length (62-70 mm) and that the device should weigh between 4.74-5.50 grams.

A comparitive study of synthetic versus natural (pdf) shuttlecocks has shown that the natural shuttle had a lower drag coefficient at low speeds compared to a higher drag coefficient at high speed. The synthetic shuttle showed the opposite trend - lower drag at higher speed.

The laws of the game even allow you to test a shuttlecock for speed, in order to ensure that you're dealing with the real thing - slight imperfections in either direction can have significant effects on the flight and behaviour of the shuttlecock in the air.

To test a shuttlecock, one should use "a full underhand stroke which makes contact with the shuttle over the back boundary line". If the shuttle lands between 530 and 990 mm short of the other back boundary line, you can rest easy.

However, a recent study of the trajectory of a shuttlecock in badminton (pdf) has suggested that a more scientific approach can be used to measure shuttlecock speed and that this could be used to "replace the traditional subjective method of the Badminton World Federation based on players’ striking shuttlecocks, as well as applying research findings to improve professional knowledge of badminton player training".

The authors of the study found that the "special structure" of the shuttlecock makes its trajectory "perform unsymmetrical motion when playing". Due to its large surface area, shuttlecocks fall more slowly than expected due to increased drag. Despite this, they showed that the air force drag on the shuttle was proportional to the square of the shuttlecock velocity. This seems to fit in perfectly with what we would expect - the harder you hit the shuttle, the more opposite drag the shuttle experiences.

Enjoy the badminton!

London Calling: Performing under pressure

When Olympians line out for their countries next week they will have years, even decades of training and preparation behind them. Despite this, they will be under immense pressure to perform at a world-class level. The ability to handle that pressure - the competitors 'mental toughness' may well provide lessons for those of us in other walks of life and how we deal with pressure.

>>This is the first in the London Calling series of Olympic-themed posts in the run-up to the start of London 2012. <<

Serryth Colbert, himself a Commonwealth gold medalist rower, and colleagues found that members of the Great Britain Olympic Rowing Team were 12% more "mentally tough" than a group of surgeons surveyed.

This "mental toughness" describes the psychological attributes to perform at the highest level and was measured by a number of broad themes. These included "having an insatiable desire and internalised motives to succeed" and "thriving on the pressure of competition". A total of six themes were measured by a survey of the rowers and the surgeons.

The results of the survey, published in the  British Journal of Oral and Maxillofacial Surgery show that the average scoring for positive responses when asked about 'comeback mentality' - the ability to overcome previous failure ranged from 53% for rowers to 40% for surgeons.

When queried about the the ability to thrive under the heat of competition, 74% of rowers responded positively compared to just 58% of surgeons.

Olympic flame at Kew Gardens (Image: LOCOG)

The whole area of sports psychology will have a huge impact on athletes at this years games. Writing for the Association for Applied Sport Psychology, Dr. Daniel Gould, who has conducted a series of research projects for the US Olympic Commission (USOC), has said that a whole range of "behind-the-scenes" factors can influence performance.

"These can range from athletes from less popular sports meeting some of the most visible athletes in the world in the Olympic village dining hall to traffic problems that disrupt an athlete’s normal training time" said Gould.

"Other distractions include having a roommate that snores or having an event scheduled towards the end of the Games but living in a village where most athletes are finished competing and are in celebration mode".

Training at the Olympic rowing venue (Image: LOCOG)

With all eyes now on the spectacular opening ceremony on Friday night, produced and directed by Oscar-winner Danny Boyle, Gould had some advice for athletes making the decision to attend or not.

“Deciding whether to attend Opening Ceremonies can be very a difficult decision for Olympic athletes if they are going to perform within 24 to 48 hours of those ceremonies. Our research revealed that it could be a wonderful, exhilarating experience and worked to motivate some athletes. Others, however, found all the standing around zapped their energy and resulted in lack luster performance. It should be discussed with the athletes, taking care to examine the potential positive versus negative consequences,” said Gould.

As one of the Olympic rowers noted: "Mental toughness is not being affected by anything but what’s going on in the race. It’s being able to block out what’s not important".


Reference: 
Colbert et al., 2012. Performing to a world class standard under pressure—Can we learn lessons from the Olympians? British Journal of Oral and Maxillofacial Surgery 50(4): 291-297. Link.