A fortnight ago, Dom Parsons won Great Britain’s first medal of the Winter Olympics as a 100-1 outsider in the skeleton. Rivals were incensed, pointing to an alleged unfair advantage given by the aerodynamic skinsuits worn by British athletes.
But the real advantage might have been underneath Parson’s sled. Over the last four years, since finishing 10th at the Winter Olympics in Sochi, he’s been working with Kristan Bromley, a four-time Olympian who took an unusual route into the skeleton, where athletes must sled down a course in the fastest time possible.
Bromley started out as a materials scientist at BAE System, helping design better equipment for the Winter Olympic athletes, before becoming one himself. Now, he’s one of the co-founders, with his brother, of Bromley Sports – an equipment company using cutting edge technology to improve performances.
In the skeleton, fine margins matter. Parsons won bronze – two hundredths of a second quicker, it would have been silver, three hundredths of a second slower, and he he would have finished fourth and out of the medals. The aim of the four year programme was to gain one or two tenths a second over the course of a one mile run, which equates to a 2-3% change in drag. “It’s very small differences down the track,” says Bromley. “There’s a lot of consistency in our sport because you can’t create any energy from the run. You need to create efficiencies in areas that you’ve not explored before, and small changes can add up.”
Advanced engineering
In 2016, Bromley Sports started working with engineering company Versarien to incorporate graphene into their products, including custom prototype ‘pans’ for three athletes at the PyeongChang games – Parsons, Kimberley Bos from the Netherlands and Alexander Hanssen from Norway.
“Utilising our graphene enhanced carbon fibre technology Bromley have been able to make significant enhancements to their already world-leading sleds,” said Versarien CEO Neil Ricketts when announcing the results of the partnership in January. “Elite sport is a clear and immediate showcase for the benefits of using our graphene technology.”
Parsons used a sled that was aerodynamically optimised for him and his geometry, explains Bromley. That included a new shape of pan created using computational fluid dynamic techniques and laser scanning. Using so-called super material graphene allowed for shapes that wouldn’t have been possible with carbon fibre alone. “Carbon fibre on its own can be quite brittle,” says Bromley. “The graphene can toughen the material systems up. When you’re at -20C and undergoing g-forces of up to 5G, toughness is a factor.”
Previously, pans have been made from anything ranging from a glass fibre system to carbon and Kevlar, but blending materials offers the best approach. It’s not just stiffness or weight – graphene helped Bromley Sports give the sled pans the material characteristics they were looking for. “It’s a blend of materials and not just one material on its own,” says Bromley. “That’s where the performance lies.”
Stronger, lighter, thinner, tougher
The work is continuing. The prototype sleds were optimised for the conditions and the track in PyeongChang, where temperatures dipped down as low as -20C. A different design and materials might be required at other events where it’s warmer – at the 2014 Olympics in Sochi air temperatures were much warmer, at around 12C. “The ambient air temperature can change the behaviour of the polymer part of the composite, and that would require a slightly different blend,” says Bromley.
“Like an F1 car, we use a lot of measurement and instrumentation. Measuring conditions and measuring behaviour under set conditions is a big part of it. We can do that on different tracks, and then we can take that data and analyse it to give us the right combination of structural requirements, and allow us to tune into the specifics of the track.”
Parsons' unexpected bronze was the only success for the graphene sled at the Games, although the winner of the men’s competition was also using Bromley Sports equipment, but not one of the new prototypes. Over the next four years, the company hopes to build its experience of using this new graphene material, and is looking for partners to help take it to other sports (for more information contact kristan@bromleytechnologies.com).
“There's a huge demand for performance enhancement and using these extremely advanced materials,” says Bromley. “As the graphene industry evolves, it will develop more understanding of the limitations and how to enhance materials. We can take those experiences and apply them to other sports markets looking for similar attributes – stronger, lighter, thinner, tougher.”
Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.