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Student power!

A team of engineering students from the University of Liverpool has broken the human-powered British land speed record three times. Now they are after the world record

The University of Liverpool Velocipede (ULV) team does not do things by halves. They designed and built their recumbent bicycle ARION1 from scratch with one goal: to capture the world record.

The students transported the bicycle to Battle Mountain, Nevada, and raced it in the International Human Powered Vehicle Association's World Human Powered Speed Challenge 2015. Aiming for that world record of 83.13mph, set at the same venue by a Dutch team in 2013, the team fell just short, but did surpass--indeed smash--the British record of 67.4mph set by Rob English at Battle Mountain in 2002.

There was early disappointment when all the male riders successfully qualified, but female rider Natasha Morrison was unable to hit the speeds required to make it through to the main event. Then, sadly, mixed weather conditions forced the abandonment of runs early in the week. However, with the sun back out, the ULV team clocked up a 69.7mph run by rider Ken Buckley to capture that British land speed record. But there was more to come. On the final day, fellow rider David Collins, a PhD student at the university, hit back with 70.6mph, only for that speed to be topped by Ken pushing to a new British human-powered land speed record of 75.03mph.

HIGHS AND LOWS

It was a rollercoaster week, with highs and lows for the team, reports ULV deputy team leader Patrick Harper. "Damage sustained to the exterior shell and steering after a high-speed impact meant working through the night on Thursday and Friday to make it possible for our riders to attempt breaking records again.

"On the final evening, the bicycle was in great condition, the riders were pumped and the weather provided perfect racing conditions. David and Ken were able to hit incredible speeds--the team were ecstatic," recalls Patrick.

So, how did they put together the machine that took them to a new British record? Rob McKenzie, new team leader of the ULV Team, explains: "Our bike, the ARION1 [it weighs about 45kg and is 2.7m long], has a carbon fibre monocoque structure that was designed to give the most stiffness possible. This allowed the effort from the rider to be effectively transferred to the road and not Into flexing of the frame. Much of the bike is made from CFR including the seat and front frame structure.

"If you look at your bike, you might notice that something is missing--it has no windscreen. Instead, we opted to mount a camera at the top of the bike, which is connected to a pair of screens In front of the rider's face. Two systems run in parallel, with one operating as a backup. On the front wheel, we use a Michelin solar car tyre. These tyres are well known for their Incredibly low rolling resistance. However, they are quite wide. For this reason, on the rear we use Schwalbe Ultremo ZX, which has a much smaller profile and would disrupt the airflow at the back less."

MASSIVE GEAR RATIOS

In order to get the bike up to speed, some massive gear ratios are required. "The main chainring has 104 teeth and is made by Royce," states Rob. "We use two separate chains on the bike. The chain from the chainring goes down to a layshaft, mounted ahead of the pedals, which has a gear ratio of about 2:1. A chain then goes from the layshaft all the way back to the driven rear wheel."

The shell was designed using computational fluid dynamics (CFD) and also taken to the wind tunnel at MIRA. "This allowed us to check our computer models against real data," he says.

But what about the riders themselves who was up to this enormous challenge? "We found our riders following a nationwide search. We eventually found the most powerful engines for the bike. The riders then went through the tough process of learning to ride a recumbent bike--which takes some serious skill. Finally, they were ready to learn to ride the ARION1." One of the most difficult design challenges was to fit the bike as closely as possible to the rider, Rob reveals. "Aerodynamic drag is related to the frontal area; therefore we wanted to make the bike as small as possible.

"We made a mock-up of the bike, using a test rig built of aluminium profile. Using this fully adjustable rig, we took 3D scans of our riders. This then gave us a CAD model around which we could design components of the bike.

"To check the shape of the shell against the rider, we had some polystyrene blocks cut to the shape of the shell and built these around the test rig. Luckily, the riders fit it like a glove!"

As there was more than one rider for the bike, the shell had to be designed and made to fit the biggest.

What of the venue where the challenge was staged? "The World Human Powered Speed Challenge takes place on an ordinary road that Is closed for 20 minutes every morning and evening," he adds. "The riders accelerate over a five-mile course, before reaching a 200m flat section where speeds are measured and recorded." One of the treasured moments must surely have been when David and Ken received commemorative speeding tickets from the Nevada sheriff for breaking the road's 70mph speed limit.

OUTSTANDING ACHIEVEMENT

Accompanying the team all the way to Nevada was Dr Tim Short, senior lecturer in the University of Liverpool's School of Engineering. "To break the British record three times In our first attempt at this challenge is an outstanding achievement for the whole ULV team," he says. "The students have worked hard, with enthusiasm, through what were difficult circumstances. The School of Engineering and the University of Liverpool are proud of what they've been able to accomplish."

Although the ULV team did not manage to trouble the 2013 world record on this occasion, it was topped by a Canadian team competing at the event when Todd Reichert and his AeroVelo team achieved a speed of 86.65mph.

This will be the target for the ULV team when they compete at next year's event. In fact, since returning from Nevada, the team has begun developing its second bike, the ARION2, based on lessons learned from the ARION1. "We believe we have an excellent chance of getting the world record next year," states Rob McKenzie. He adds: "We would like to thank Rathbones, our sponsor. Without its support, this wonderful project would not have been possible."

Rathbones' chief operating officer Andrew Butcher describes ARION1 as "a triumph of British education, industry and sport. As investment managers, we seek to invest in future technology and it is a privilege for us to help make possible the team's success in smashing the British record".

For more pictures and background on the contest, visit: http://ulvteam.co.uk.
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Title Annotation:RECUMBENT BICYCLE
Publication:Engineering Designer
Geographic Code:4EUUK
Date:Jan 1, 2016
Words:1176
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