TESTING TIMES
comprise two tunnels, one for cycling
and other sports, such as speed-skating,
skeleton, running and wheelchair athletes;
and the second for testing fabrics.
WORLD INTEREST
TotalSim’s managing director Dr Rob
Lewis comments: “If we can pool the
right things together, then we believe that
organisations will come from around the
world to take advantage of the facility.”
The software and control systems that
both facilities use will be the same. The
tunnel is designed to be operated with a
Beckhoff control system. Instead of using
a PLC system, the Beckhoff IPC system
allows the tunnel’s operators to perform
all of the data collection, including the
basic wind tunnel operational parameters,
wind speed and load cell numbers.
That is then fed into a bespoke
LabVIEW-based data acquisition and
analysis tool developed by KWSP, which
includes a bespoke front-end interface.
This data is brought together with data
from the vision control system, which is
made up of three GigE cameras. Of these,
one looks at the frontal area; one looks
from the plan view, down onto the cyclist;
and one is side-on. Those images are
all aligned with the data, so at any point
in the data stream the cyclist and the
Boardman analyst can look at the drag
from any one of those views.
An outline can be extrapolated from the
data and overlaid on the live video feed
to show the optimal position the cyclist
should adopt, in terms of optimum drag.
This is then projected on to the fl oor of the
can see the target position they’re trying to
achieve, as well as the graphs and metrics
that back this up.
The bicycle itself is fi tted to a circular
platform in the centre of the test room, right
in front of the opening from the bell mouth
section of the wind tunnel. The platform
can accommodate any size of bicycle, with
an adjustable clamp for the front axle. Both
axles are clamped to the platform, ensuring
the wheels are in contact with rollers that
are connected with a belt, so the front
wheel turns at the same rate as the rear
one is being driven. The whole platform can
yaw up to 30° left and right to simulate the
effect of side-winds.
FORCES AT WORK
This platform is seated on top of a series
of four load cells that measure, calibrate
and cancel out the vertical force and
moments caused by the athlete as they
pedal. Salter adds: “At the back is a load
cell that measures drag. There are also
two side force ones, because the air fl ow
is never regular around the athlete and,
as we yaw, it we’re able to take out the
impact of side force.”
For athletes using the wind tunnel,
accuracy is all-important. They want to know
that the data they’re producing is applicable
to real-life marginal gains on the track or
road. What’s important to Sports Aero
Solutions is to be able to prove that the
results in the tunnel are repeatable.
Despite the fact that from day-to-day
an athlete’s performance can be affected
by many different factors, the data
being collected must be as accurate as
possible. So, how do you make sure of
that repeatability? “It’s a really high-tech
solution,” Salter jokes. “We’ve got a roof
box from Halfords that’s mounted in the
wind tunnel and that’s our validation object.
It’s always the same, and a really good,
aerodynamic shape. We’ve validated that in
the wind tunnel to get the correlation and
we can put that same roof box back in and
see if it’s still measuring the same number
as it was last week or last year.
“Repeatability is very important; it
doesn’t matter whether the number is 8 or
9, what you don’t want to do is measure
8 and next day, with exactly the same kit,
measure 9. If you’re looking for a trend
of improvement, you need to have that
repeatability. The roof box test gives us
a neutral test body that no one can argue
with,” he points out. Looking forward, there
are also plans for other facilities where
wind tunnels could be used.”
SMART MANOEUVRE
Wih the R&D facilities at Silverstone,
one could envisage entire road stages
being simulated via smart glasses, while
adding servo drives to add resistance
to the rollers in the wind tunnel would
simulate gradients. This could be used to
train professional riders to optimise their
efforts across an entire race, such as
the Tour de France. British Cycling has
been at the top of its game for the past
decade. With the Evesham and Silverstone
tunnels in full operation, that could continue
for many years to come.
wind tunnel in front of the athlete, so they
Cycle of success
For more than a decade, Rob Lewis of TotalSim and Olympic
gold medallist Chris Boardman, left, worked with some
of the best athletes in the world to explore the effect of
aerodynamics on their performance. Although hugely
expensive, the advances in aerodynamics they achieved
were enormous. Because of this, Boardman and TotalSim
wanted to make aerodynamics exploration available to the
wider sporting world. In 2015, they teamed up with Kieron
Salter of KWSP to form Sports Aero Solutions to design
and manufacture sport-specifi c wind tunnels, with a goal of
providing cutting-edge knowledge for everyone, from sports
enthusiasts to elite athletes and coaches.
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