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LIAM McHUGH: Bobsled is one of the fastest, most exciting,
and most dangerous sports in the Olympic Winter Games. Reaching
speeds close to 100 miles per hour, these two- and four-person
sleds roar down an icy track complete with sharp turns
and spectacular straightaways.
STEVE LANGTON: I just couldn't believe that that sport was that
rough and that loud. It's controlled violence.
McHUGH: What may seem to be just a chaotic joyride, is actually
the product of meticulous research and design from top
engineers who strive to make sleds faster and tracks safer.
MICHAEL SCULLY: Let's take a look at the top bumper radius.
McHUGH: Michael Scully is the creative director of Global
Design at BMW DesignWorks USA in Newbury Park, California, and
the lead designer of team USA's new 2-man bobsled. His goal -- to
help the U.S. win gold in the 2-man event for the first time
since 1936. Using a sleek, innovative design and cutting
edge technology, this new sled reduces drag, the force that
resists the sled's movement down the track, optimizing
aerodynamics to create the next step in bobsled engineering.
MICHAEL SCULLY: We hope that this is the best tool available
to them. People have invested their lives in these careers and
making these achievements hopefully in the form of an
Olympic medal is something that we take very seriously.
McHUGH: One of the biggest challenges for designers is the
rules regarding the weight of the bobsled. The International
Bobsleigh and Skeleton Federation requires that a 2-man bobsled
weigh no less than 374 pounds when empty and 860 pounds with
crew and equipment. To make a faster sled, but stay within the
weight restrictions, Scully utilized his prior experience as
a race car designer, incorporating lightweight
materials such as carbon fiber and Kevlar, and fashioning them
into a sleeker and more aerodynamic sled.
SCULLY: The overall approach is a bit different. Absolutely
minimized frontal area as well as cross-sectional area
throughout the form. That's something that we
put a large emphasis on.
LANGTON: What makes the BMW sled so much different aesthetically
is the carbon giver cowling. It's very, very sleek and every
measurement, every detail is Michael Scully's brain child.
McHUGH: Once the sled is pushed from the starting line, gravity
is the only force causing it to accelerate down the track,
therefore it is crucial that any force that might slow down the
sled be minimized.
SCULLY: You need to consider all of the different contacts that
the sled will encounter down the run, which there are a lot of them.
McHUGH: A bobsled does not travel in a straight line.
Instead, it bounces and bobs. Any contact that the sled has
with the side of the track will cause it to slow down.
By distributing the weight in strategic parts of the sled
Scully was able to keep it more stable.
SCULLY: The ability to tune the weight balance either forward
to back or sideways is something that is a new capability for
the U.S. team.
LAURENZ SCHAFFE: This is really interesting conceptually.
McHUGH: Once Scully and his team decided on the final design,
a three-dimensional model was created for further testing.
Tweaked and perfected through both virtual and physical wind
tunnel tests, a prototype was then constructed and tested on a
track with the athletes.
STEVE HOLCOMB: We took it down and it was a pretty good sled.
It came out of the box pretty fast, and I think it
was pretty motivating.
McHUGH: With sleds like the BMW 2-man bobsled getting faster,
another concern for designers and engineers is the safety of
the track itself. Dr. Mont Hubbard is a professor emeritus
in mechanical engineering at the University of California-Davis
and has been funded by the National Science Foundation.
MONT HUBBARD: I think what contributes to them being so
treacherous is a lack of understanding of this motion on
a surface, and how the surface can interact with the object to
eject the object from the track.
McHUGH: On every bobsled track, there is a section of the
surface called a fillet, a small circular rounding at the point
where the vertical wall and horizontal wall of the track
connect. The fillet works to keep sleds in line on the
straightaways, but in the curves of the track, Hubbard believes
it can cause a problem.
HUBBARD: If you're going that direction, the track can go away
from you, and all of a sudden, there's no track there to
support you anymore. And then, if at that moment when you leave
the track, you have enough velocity to fly past the rest of
the track, then you've been ejected.
McHUGH: Hubbard proposes that removing the fillet from the
curves of the track could help prevent athletes from being
ejected or thrown from the sled when it goes too fast
around the curvature.
HUBBARD: If the fillets are gone, then I don't think
ejection from the track can happen.
McHUGH: Though Hubbard's research won't influence the
track design for the Sochi games, new engineering endeavors
like his represent increasing advances in bobsled track
safety... which may be necessary if designers like Scully
continue to push the sport of bobsled down the fast track.
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