For many, it was one of the most thrilling moments of this year’s Winter Olympics: British athlete Amy Williams hurtling head-first down the icy chute of the Whistler bobsleigh track to win the gold medal in skeleton bob — the country’s only medal of the games. Williams’ skill and bravery are beyond doubt, but she was keen to share the credit for her win with the team behind her sled, nicknamed Arthur.
Arthur was the result of the dramatically-named Project Blackroc, a research and development effort bringing in sports scientists from the University of Southampton, expert sliders (as bobsleigh and luge atheletes are known) from the British Bob Skeleton Association (BSA), UK Sport and aerospace engineers from BAE Systems. Designed to build on the success of British sliders in achieving two silver medals in the 2006 Winter Olympics in Turin, Project Blackroc is named after the two Southampton engineers who led the project, Rachel Blackburn and James Roche. Both were employed full-time on the four-year project to develop a sled to maximise the chances of British athletes in the next Games.
Skeleton bob might seem like a puzzling sport to apply engineering know-how to, and Rachel Blackburn admits to being puzzled at the outset of the project. A naval architect by training and a competitive sailor (‘although I never quite made it to the Games as an athlete,’ she said), she was keen to remain in touch with Olympic sport and jumped at the chance to gain her PhD through working on the project. ‘But it was hard to understand, in the beginning, exactly what this sport was, why people did it, and to work out what the current equipment was doing,’ she said.
It is, indeed, tricky to work out. To the spectator, skeleton bob appears to consist of an athlete sliding very fast down a bobsleigh track lying face-down on a tea-tray, with their crash helmet-encased head leading the way. Leaving aside the question of why anyone would want to do that, Blackburn and Roche — who is also a naval architecture graduate — worked with BSA performance director Andi Schmidt, a former skeleton world champion, to figure out the underlying mechanics and techniques.
‘It does look like a tea-tray from the outside, but that’s good because it means that other nations can’t see what we’re up to,’ Blackburn said. ‘The bit you can see is the belly-pan, which is made from glass-fibre reinforced plastic, and protruding through the bottom of that are the supports for the runners, that are in contact with the ice. On top of the pan is a layer of foam that the athlete lays on, and then there’s a saddle which is a steel frame which supports the athlete in the right position on the sled.’
It’s what’s inside the pan that counts: a complex steel chassis which, much like the chassis of a racing car, provides the sled with its structural integrity and handling characteristics. ‘You want the chassis to be relatively stiff,’ Blackburn said, ‘but the athlete steers the sled by shifting their weight; they apply pressure with their shoulder and the opposing knee, using that force through the padding to try to twist the sled.’
Like all sports, skeleton is heavily regulated, and the dimensions of the sled and the materials which can be used are proscribed by the governing body. However, Blackburn said, as long as these rules are adhered to, designers have free rein.
‘In the beginning, we tried to see if we could modify existing equipment, but there were so many little tweaks we wanted to apply that we decided to start from scratch,’ she said. ‘So we took the range of athletes that were in the British skeleton team, from tall, heavy males to shorter, lighter women, and we tried to see whether we could make one sled to suit all of them, or to go for a modular approach that could be adapted to suit each individual.’
The latter proved to be the best option. The Blackroc sled — whose precise design is still closely-guarded by the BSA and UK Sport — includes adjustable components and interchangeable parts to fit the sled to the athlete’s body size and shape; these also allow the athletes to set up the sled’s runners to cope with the varying demands of different bobsleigh courses and the conditions of the ice when they have to slide, which vary with weather, time of day, and their place in the order of competitors. The sliders are fixed on a ratchet mechanism that allows them to be adjusted quickly, precisely and repeatably.
As well as engineering the chassis mechanism, the researchers also conducted some 200 hours of wind-tunnel testing in Southampton, and used Sheffield Hallam University’s computational fluid dynamics expertise to fine-tune the design, which was then built by BAE Systems’ engineering team. The result, in Amy Williams’ Arthur’s case, was a top speed of 143km/hr on the Whistler track.
And why the name? ‘In my sailing background, we always name our boats,’ Blackburn said. ‘When we got to the point that we had three sleds all in development at the same time, and I was losing track of what was happening with each one, I asked the athletes to name their sleds. Amy decided that Arthur was the only possible name for hers; the others were called Frank and Rita.’
The BSA ‘development squad’ of young skeleton sliders were equipped with Blackroc sleds last year, and are now using it to fine-tune their performance while training for the next big goal, the 2014 Winter Olympics in Russia. ‘We start by taking a basic look at the athlete, their proportions, geometry and power output, which we get from the strength and conditioning team,’ Blackburn said. ‘That gives us a basic setting for their sled, so they can learn the feel of the sled and how to slide and steer. That process can take a couple of years, before we can start putting refinements into the sled design.’
For Blackburn and Roche, persuading the athletes of the advantages of the new sled was the most challenging part of the project. ‘We got to the point where we were making improvements to the design scientifically, and backing those decisions up with engineering,’ she explained, ‘and that was very rewarding. But then we had to implement the thing, with an athlete who might be reluctant to change. We had responses like “I’ve been using the same sled for the past eight years, why should I use this one?”’
In Amy Williams’ case, it took a ten-day training course with the new sled in 2008 to convince her of its worth. ‘In the first event she went to, she came sixth — and in skeleton, the first six finishers get medals,’ Blackburn said. ‘Four months later she achieved fifth position at the world championships, despite having this brand-new equipment. Then both our athletes won the silver medal at the world championships the following year. It became a lot easier to persuade people after that!’
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