When amputee athletes put on their running blades, they suddenly appear superhuman, with gleaming carbon fiber replacing the sub-par human legs most of us possess. Before double-amputee Oscar Pistorius made a name for himself as an alleged murderer, there was even a lengthy debate over whether his blades gave him an unfair advantage when he competed in the 2012 summer Olympics—that is, whether his carbon fiber limbs gave him an advantage over athletes competing with natural legs and feet.
But even with the debate over Pistorius's advantages, the public dialogue missed one crucial point: running blade technology still has a lot of problems. It's not, in fact, better than human legs.
At last year's Industrial Designers Society of America (IDSA) conference, Paralympian runner Blake Leeper, who was born without legs below the knee, gave a keynote presentation. He stood on his blades as he challenged the audience of industrial designers to help advance the technology, which hasn't changed much in recent years.
Two companies, Altair (known for product design and development) and Eastman (a chemicals and plastics manufacturing supplier), decided to take Leeper up on his challenge to come up with a series of concepts for next-generation blades. For four and a half months, teams from the two companies consulted with Leeper and tweaked their designs, emerging with what they call an "F1" concept—a top of the line, premium set of blades that are fit for an Olympic or Paralympic athlete. The design is being officially unveiled this week, at the 2014 IDSA conference.
Before coming up with the concept, Altair and Eastman went over the many challenges with today's blades that Leeper outlined. These include issues with speed, psychological comfort (today's blades rely on suction, and there's the potential for them to fall off), traction, and agility. After much work, including a session with students at California's Art Center College of Design in an immersive design workshop, the new blades emerged.
Leeper's current running blade consists of a sleeve at the top that covers his leg and the socket, a one-way valve that builds up suction to hold the blade to his leg, bolts to hold the blades in place, and a spike plate on the end. The new design, as you can see in the images here, has differences large and small.
First, Altair and Eastman focused on adjusting the spike plate. Running blades are normally flat planes, causing runners to lose significant energy at turns. The new blade acts more life a human foot. "There's a curvature to the bottom of the blade that will act like an ankle, giving increased speed and efficiency on corners," says Mike Kidder, Altair's senior vice president of corporate marketing.
The second step was to change the design of the blade, which has been mostly the same for the past 10 years. "The focus is on redirecting energy so that it forces more power forward instead of into the ground. It twists at the top, redirecting energy that he’s losing with the current blade setup," says Kidder. After testing the drag force of the current blade and the new blade design through virtual wind tunnel software, Altair found that the new, more aerodynamic blade decreases drag force by 57%—possibly resulting in a half second faster return on the 400-meter race. In a race that take less than a minute and is often decided by fractions of a second, that difference could be a big deal.
"We can tune the blade so it competes or is equivalent to a human leg," says Kidder.
To prevent anxiety about the blade falling off (Leeper's prosthetics once fell off during a baseball game as a kid), a fabric shroud and latch lock the socket into place. When Leeper hits the ground, the shroud flexes, and when he pops up, it holds strong. Altair and Eastman also developed a full-body suit—kind of like a compression suit— that integrates with the latching system. In a way, this allows Leeper's blades to work more fully with his body.
While Leeper has been integral in the design process, he hasn't yet tried the new blade concept in person. That's the next step. The concept meets Olympic regulations, so he could theoretically use the new blades—or just pieces of the new design—in the 2016 Olympics.
While this design is made for a professional athlete like Leeper, Kidder imagines that similar concepts could one day be used for non-athlete amputees. "With the suit idea, we scaled that back into various designs. It could just be a pair of shorts that integrate with the socket," he speculates.
Leeper, for his part, is hoping to compete in the next Olympics against able-bodied competitors. An upgraded set of blades could help get him there.