Partnership could lead to winning finish

When Usain Bolt smashed the then 100m record at the 2008 Olympics in Beijing, he wore personally customized golden spikes that had “Beijing 100m Gold” emblazoned across them. When Ryan Hall, the U.S. half marathon record holder, wanted to train fast for the Olympics, he ordered a pair of shoes made from Japanese rice husks.

It’s only natural that in the competitive world of athletics, athletes will do everything in their power to be the best. With a slew of paralympians and world record holders on the University’s Wheelchair Track and Road Racing Team, there are no exceptions.

“You can improve with training and psychological factors, but in our sport, equipment is also a huge factor,” said Adam Bleakney, the head coach of the University’s Wheelchair Track and Road Racing Team.

For the last two years, Bleakney has paired up with graduate students from the Department of Aerospace Engineering to conduct a series of tests — all in the hopes of finding a way to make racing wheelchairs go faster.

At the recommendation of a student athlete, Bleakney approached Mike Bragg, executive associate dean for academic affairs in the College of Engineering, in the spring of 2007.

Greg Busch, a graduate of the University, had always been interested in the aerodynamics behind bikes, jumped at the chance to lead the research.

“There has been a real lack of scientific data (in the past),” Bleakney explained.

While a study was done in the 80s at the University, Bleakney confirmed that the partnership study was the first comprehensive research on making improvements to racing chairs.

With the project set in stone, Busch and his team of graduate and undergraduate students had one objective in mind: to reduce the aerodynamic drag.

For non-scientists, there are two kinds of resistance that an athlete encounters when pushing a wheelchair: rolling resistance (from the tires on the ground) and air resistance (aerodynamic drag). Rolling resistance is more important at low speeds, while air resistance is more important at high speeds.

Instead of designing a new racing wheelchair, Busch and his team decided to make modifications and additions. The result was adding a fairing — the equivalent of a windshield on a motorcycle — to the racing wheelchair, Busch said.

To test whether adding a fairing would make a difference in the wheelchair speed, the aerodynamics team conducted two tests: wind tunnel testing and coastdown testing.

But before the group of engineers could conduct the wind tunnel testing, they had to secure funding from the University to build a reduced-scale model that would fit in the wind tunnel. The result was turning the group of researchers into a campus Registered Student Organization, or RSO, “Racing Wheelchair Aerodynamics Design Team.”

With permission from the aerospace engineering department to use its wind tunnel and the model chair built, the team then used mannequins the size of a two-year-old to represent the equivalent of a 5 foot 6 inch athlete.

The results were surprising.

“The fairing was our biggest find,” Busch said. “We were surprised when we got 12 percent (reduction in drag speed) — our goal was 5 percent.”

To put it into perspective, 12 percent equated to a couple of seconds — “Enough to separate five to six places in the 2008 Beijing Olympic Paralympics Games.”

The wind tunnel testing also provided new findings on how to reduce wind resistance through two areas: the body movement of the racer and configuration of the wheelchair.

“When the feet are exposed and they are in the wind, they are dragging,” Bleakney said, referring to the body configuration of the athlete.

The testing also discovered that the lower the angle the racing wheelchair is positioned at, the more aerodynamic it is.

Despite the affirming results, Busch and his colleagues decided to complete another test, as the wind tunnel testing had only used partial scale model chairs.

With the coastdown testing, the team decided to use full-scale chairs to measure the deceleration of the racing wheelchair as it coasts (with and without a fairing). To do this, Busch and his team built a track in the West Hall of Memorial Stadium. The full size fairing would be built from carbon fiber, measuring roughly 17 inches wide and 7 inches tall.

The test consisted of Bleakney pushing up to a certain speed and then coasting, letting the wheelchair roll on its own. Timing blocks were used to measure the time it took the chair to coast through seven 25 feet intervals, with and without the fairing.

Busch and his colleagues were once again met with positive results. After a series of tests, it was 98 percent guaranteed that the fairing reduces air resistance.

Aaron Pike, a member of the wheelchair racing team, confirmed these results in the first race where he used the fairing.

“At the Peachtree (10 kilometer in Atlanta), the fairing gave some benefits,” Bleakney said. “He out-coasted one of the top guys in the world during the descending.”

Because the research was completed in the spring of 2009 and most of the research team members have graduated since then, Bleakney and his athletes are left to test out the fairing themselves.

Aside from using the fairing at two major races this past summer, Bleakney said his athletes are looking to debut the fairing at their longest distance yet: the upcoming Boston Marathon in April.

But don’t rule out any additional fairing research in the near future.

“It’s about always trying to push the envelope and find ways to make the chairs better and improve performance,” Bleakney said.