HIGHER EDUCATION
Aim
high
A London South Bank University project to develop a high-speed competitive recumbent racing
bicycle has successfully moved from faculty research to student extracurricular initiative, and has its
sights on reaching 93mph
This story begins with the ending of
another one: the death of cycling
journalist Richard Ballantyne.
Attending the funeral in 2014
were London South Bank University
professor of computational uid dynamics
Glen Thompson, and recumbent bicycle
designer Mike Burrows. They met, and
decided to team up to develop the world’s
fastest human-powered bicycle.
While Burrows made the carbon- bre
bicycle frame, Thompson focused on the
n-shaped faring. His starting point was
the published dataset of the Varna, a
series of record-breaking human-powered
bicycles devised by Georgi Georgiev, which
Thompson used to set up and validate the
computer model. A simulation included 12
million elements. Then began the work to
re ne key areas: nose, footbox, tail, wheel
openings. He worked particularly on the
zone where air ow changes from laminar to
chaotic, where drag forces are high.
Last September, their nished design,
dubbed the Soup Dragon, competed. The
World Human Powered Speed Challenge
runs on a ve-mile long stretch of straight,
level resurfaced public road in Battle
Mountain, northern Nevada. Each team
gets a total of 10-12 runs over the weeklong
competition; speed is measured in the
nal 200m.
The 19kg vehicle consisted of a carbon-
bre frame with recumbent rider’s seat
and steering stick, toothed chain-ring
mated to the front wheel in a direct-drive
con guration, huddled – with rider – inside
a thin exterior shell viewing the road ahead
on two battery-powered redundant video
cameras and screens. The end result of
The original steering / transmission unit
years of work was a fantastic rst result -
53mph.
The attempt marked the end of the
beginning; both men retired from the
project, and Thompson retired from LSB
University. His former project assistant,
Barney Townsend, senior lecturer in product
design, stepped up to guide the project, led
by an entirely new project team: students.
PASSING THE BATON
Townsend explains: “The whole idea of
the project from the outset was to get it
started and hand it over to the students
as an ongoing extracurricular project in
the vein of Formula Student – which was
exactly what he did.”
“Getting to that model to that level in
the rst place took many years of highlevel
research. Once we’ve got that, you
can, at an undergraduate level, discuss
the principles and introduce them to
what’s going on, and explain various
different factors, and then it’s quite easy
for them to further explore iterations in the
shell shape and so on.”
Over the past year, Townsend and the
students have been adjusting the design,
with a new, one-race focus. He explains
that last year, the design competed in a
second race, the British human-powered
speed records, which take place on a
circular track because of the lack of
empty straight roads in this country. The
lightweight design of the vehicle helped
to reduce the effort required to get to top
speed.
But by reducing weight in the vehicle,
the designers also reduced its structural
integrity and stiffness. As a result, the
single-skin breglass airfoil with stiffeners
actually deformed under aerodynamic
loads when it was raced in the Nevada
desert. “Having got there, and seen the
event and the track, it was clear it could
be unsafe in a nasty accident.” In addition,
the rider, Russell Bridge, a veteran
competitor of human-powered races,
complained that at top speed steering felt
loose, oppy and wobbly: a scary feeling at
any speed, much less highway velocities.
First morning
run
10 www.ied.org.uk
Bas Fotogra e
/www.ied.org.uk