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Science, Maths & Technology

Legs - Diary

Updated Friday, 2nd June 2006

The Science Shack moves to a Northamptonshire speedway track to see how fast Adam Hart-Davis' legs can carry him.

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Chris starts work on the Shack bike Copyrighted  image Icon Copyright: Production team

6th November before noon
Today, Adam is in Northamptonshire at Rockingham Motor Speedway - Britain's fastest motor racing circuit - to see how fast he can propel himself using his own (he's only human) power, Science Shack technology and a BBC budget. The Champ cars that zoom round this track average 215 mph. Will Rockingham need to build a faster track for Adam and his four-wheel bicycle?

Bicycle building begins. The Flywheel Bicycle - built by Chris, designed by Jem (and not driven by Italians if they can avoid it) - is one of the 'technologies' the team are working on to help Adam propel himself into the record books. He is going to cycle as fast as he can - with the bike jacked up - to 'charge' the flywheel (Jem says the flywheel will be spinning at over 200 mph, geared up by a little wheel between the back bicycle wheel and the flywheel).

The bike will then be dropped back onto the floor and then the flywheel will be lowered back onto the back wheel. What happens next is anyone's guess - but I have just been told Adam has gone off to buy a new crash helmet.

Jem, the inventor of the flywheel-propelled bicycle is confident in the scientific principles that underlie his brilliant design. He reveals its secrets: 'The polar moment of the flywheel which we'll refer to as 'I nought' gives an idea of its rotational inertia. Multiply this by omega squared - omega obviously being the angular velocity of the flywheel - divide it by two and you get the kinetic energy stored up in the flywheel. It's as simple as that'. Yes, Jem, as simple as falling off a bicycle.

The four-wheeled bicycle that the team is adapting for Adam's new human power record is still looking somewhat abandoned in the pit stop workshop. The idea is to attach massive plastic tubes to the back of the bike which will serve as pop bottle rockets.

All Adam needs to do is pump them up by hand or foot, get cycling, then release the rockets. But last night the manufacturers of the tubes (which can withstand huge water pressure) told Science Shack producer Jonathan that for some inexplicable reason the PVCU plastic they are made from cannot withstand even a piffling amount of air pressure.

So new tubes are being sought out at this very moment.

Adam has a moment alone to gather his thoughts and ruminate on the nature of existence before firing himself down Britain's fastest racetrack on a rickety bicycle connected to a bank of huge water bottle rockets. You too, might need to put your life in perspective if you were Adam and could see what was going on in the Science Shack and Rockingham's Motor Speedway pit stop workshop.

Adam and the Blueyonder team Copyrighted  image Icon Copyright: Production team

6th November after noon
Jem looks up from his cluttered workshop desk as he saws through £1.20s worth of MDF board to make a flywheel for his Flywheel Bicycle, and sees £100,000 worth of human-powered machinery parked out on the track.

The Blue Yonder, Britain's fastest bicycle has arrived with its designer Chris Webb. Chris has just come back from Nevada in the USA where he and the British team have just been competing for the world human powered speed record. They didn't win (this was the first year they competed) but they did manage to get up to 65mph and reckon they have learned enough to beat the world record of 80.5mph next year.

Powering Blue Yonder was Jason Queally - Britain's Olympics 2000 Gold Medalist in the cycle time trials. Blue Yonder's fibreglass frame is moulded around Jason's shape for maximum aero-dynamism. Chris, who designed the bikes for the British Olymic team and is a motor racing car designer by trade, loves the magic of human powered machinery. 'It's amazing to see a silent machine go past you at 65mph with only the sound of the wind rushing past it,' he tells Adam.

Adam is keen to get into Blue Yonder's driving seat but designer Chris Webb looks a little queasy about the prospect. Adam is quite powerfully built and quite clearly too big (by that we mean too tall of course) to manage this feat of high tech limbo dancing. Adam notices that the handlebars are far too low to be comfortable for the man of average waistline.

Adam is finally comfortably seated in Blue Yonder. He learns that if he cycles off into the distance alone he will need a team of 'collectors' (the official term) standing by to stop the bike toppling over with him inside it. Designer, Chris Webb, also tells him that there is too much wind here at Rockingham today to risk driving off anyway. Not the most practical machine for shopping or carrying a girlfriend on the handlebars!

3.30 pm
Jem stands proudly by the Flywheel Bicycle he designed all by himself. Remember that Blue Yonder - Britain's fastest bike - reached 65mph and cost up to £100,000. Jem's bike may have cost up to £13.04 (this includes the cost of the bike he probably dredged up from the Leeds canal) - almost 10,000 times less. So if it reaches just 0.001 mph Jem will be more than satisfied.

3.45 pm
Jem is ecstatic. The Flywheel Bicycle has performed beyond his wildest dreams. As predicted he thumbs his nose and waggles his fingers at the Blue Yonder team by comparing the cost of his technology with theirs.

In an exclusive interview with the Science Shack website he comments 'we have shown that in principle you can easily accelerate from 4 mph to 6 mph using a very very very low price flywheel. I would say that for mph per penny budget it was quite a successful job'.

4.30 pm
The atmosphere is tense in Action-Man land as one of their kind braves 'Science Shack' producer Jonathan's extraordinary propulsion technologies.

Our volunteer stunt Action-Man sits impassively in the driving seat as Jonathan winds a baked bean tin to the top of the gallows hanging over the back of his vehicle. When the tin is released our stunt hero shoots (perhaps 'travels' is a better word) across the very same ground 'traveled' by 220 mph Champ cars.

Action-Man's vehicle comes to a halt a good four yards away and he falls out of his seat. Unfazed by the trauma he is anxious to get back into the driving seat and test drive another of Jonathan's machines (at least this is the gist of the imaginary conversation Jonathan had with him during the experiment).

4.45 pm
Action-Man eagerly awaits the moment when Science Shack producer Jonathan, will release the twin pronged mouse trap device on his vehicle - an idea sent in by a viewer. The mousetrap vehicle manages to cover several yards before Action-Man, as usual, loses his balance and falls sideways out of his seat. He is currently lobbying for the mousetrap-powered vehicle industry to fit doors to its cars.

Don't forget to see what Adam and the team get up to tomorrow when Action-Man hands the steering wheel and handlebars to Adam who will be zooming down the race track here at Rockingham Speedway on a pop bottle rocket propelled bicycle.

Three generations of Avery - and Adam Copyrighted  image Icon Copyright: Production team

7th November before noon
Day two at Rockingham Motor Speedway in Northamptonshire - Britain's fastest motor racing circuit. Today Adam has to do a lot more of the physical work as yesterday's experimental phase using other human guinea pigs (Science Shack's Jem and Chris) is over. How fast can he propel himself using his own (he's only human) power, Science Shack technology and a BBC budget?

Desolate scenes in the workshop greet the crew this morning. As usual Jonathan, Chris, Jem and Lou worked late into last night to prepare for today's big water bottle powered cycle run - but they are behind time after they learned the plastic water rocket tubes they were using are no longer deemed safe by the manufacturers to pressurise.

Jonathan is to be found wrestling with a tyre from a dismantled four-wheel bicycle which is supposed to carry Adam to record breaking speeds this afternoon.

At Science Shack all our experiments are 'what you see is what you get' - i.e. most of them have never been tested before. Jem has calculated every last equation and is convinced the air pressurised water tank on the back of Adam's vehicle will, at the very least, shower the cameramen with gallons of water.

Adam is a very relaxed traveler. His waterjet-powered vehicle is still in pieces but he continues to read his newspaper with no sign of anxiety. The team are still reeling from the news that the plastic tubing they had lined up was not going to be safe enough to pressurise with air but they feel confident the metal tank will work.

The Great Pop Water Bottle in the sky has just burst all over Rockingham and Mike Wilkie our cameraman. The elements, time and technology are against us at the moment - but the Science Shack team always seems to pull the odd (bedraggled in this case) rabbit out of their collective hat when the pressure is on them.

Adam takes a recumbent bike ride 10am
Adam tests out the power of his legs on the Rockingham Speedway track. He has high tech professional motor racing timing gear that clocks his speed on the rickety old Science Shack bicycle at 21 mph.

He then squeezes into the Windcheetah trike, which, being recumbent and made of super light materials, goes much faster than the conventional bike. Adam is hampered by wearing a bulky jacket and the wrong shoes (his feet keep slipping off the pedals) and only manages 24 mph.

But it is obvious to him that the Windcheetah has the potential to go much faster. Bob Dixon of Advanced Vehicle Design which makes the Windcheetah trike, explains that the recumbent bike - invented in 1932 - goes much faster than the traditional bicycle but that it was banned by the ruling body that governs the sport of cycling.

The Windcheetah is made of super light materials and is welded together with glue. Bob says that amateur recumbent cyclists regularly make a nonsense of the British (traditional) cycling records.

Producer Jonathan checks whether the 'bicycle stability' test works by throwing the Science Shack bicycle forward down the racetrack.

As we know, your bicycle's sensitive front wheel falls to the left or right in a kind of snaking movement when the bike leans to the left or right. This is what gives bicycles such stability.

When Jonathan throws the bike forward with the handlebars turned round (the brakes have been removed so as not to get in the way) the bicycle stays upright much longer.

But if someone rides the bike with the handlebars turned round it will, paradoxically, be less stable because the front wheel stays more aligned. So if the rider leans over the bike falls sideways more easily.

The Avery Family The Avery family, our first pop bottle rocket entrants, arrive for the great race. Kennita, 13, is an expert on which diameter tubes you can use to propel the vehicles forward 'we tried 8, 10 and 15 millimeters and 15 millimeters is best' she says.

Despite this great technical know-how she insists that beauty is more important than speed. Consequently her design, 'The Clown', is dressed up with a lace ruff and a red woolly nose. Adam is concerned these will make for a lot of wind drag on her vehicle but Kennita is not bothered.

Samantha's entry is called 'The Garden' and, like Kennita's model (and their brother Zak's), has a bottle pointing upwards. Samantha says she thinks Adam's water bottle rocket propelled vehicle won't work because the cylinder is lying flat instead of upwards, so all the water can't come out. Her Dad says the angle makes no difference - that air pressure is more than enough to expel all the water.

Zak is worried, above all, that his sister Kennita's bottle might spring a leak 'because Mum sat on it in the hotel last night'.

All entrants are now here and ready to go.

Three generations of pop bottle rocket enthusiasts arrive - Grandad, Dad and Nick Labsvirs. Grandad retired recently and turned to model making and his workshop has been raided by Nick to build his Pop Bottle machine. It sets itself apart by having a special anti-soaking device which allows you to fire it off without mishap, says Nick. He has also turned the exit nozzle upwards to keep the car pressed down on the road. Earlier models tended to take off.

Adam burns rubber Copyrighted  image Icon Copyright: Production team

7th November after noon
The Pop Bottle Rocket Championships begin and Adam blasts himself down Rockingham Speedway with a water rocket.

Pop bottle rocket time trials begin. The Avery family is still worrying about their damaged vehicle, which received a sitting on by Mrs Avery last night in the hotel bedroom. Nick Labsvirs is confident he will remain the only dry contestant at the end of the Championships. Nick Taylor is concerned that his four CD wheel driven car might do a circle as it has frequently done in the past.

Nick Labsvirs dad pumps up his son’s vehicle with Nick crouching down behind it. It is the envy of all the contestants, above all for its anti-soaking tube attached to the back.

Imagine our shock when his car shoots away before being counted down, crashes straight into director Paul Bader’s foot and yes, you’ve guessed it, sprays Nick and the cameraman with two litres of water.

Nick regains his composure when his fantastic vehicle is declared the winner on its second run – the only car to get anywhere near the finishing line.

The fears of the contestants are mostly born out. Their vehicles shoot off in all directions with the most acrobatic being Mr Avery’s, The cause of the problem, according to Mr Avery's son Zac -11 years old - is its over-sized front wheels.

The CD vehicle Nick Taylor’s CD wheel driven machine is fast but, as predicted, can only go in circles.

After lunch Adam's water rocket vehicle is still in bits. But by 2.45 it is ready for a stability test. Producer Jonathan tests it at 40 mph and it stays upright - and what's good enough for Jonathan is good enough for Adam.

Now it is time for Chris to get on board and see what happens when the team pumps up the tank and opens the tap at the back. A massive spurt of water sprays across the Pits car park and makes Jem and Chris very happy.

A last minute safety test is carried out on Action Man. He is sitting in Jem's superior pop bottle rocket device. Key to its success is Jem's 'spit valve' which he is thinking of patenting.

It works with a little rubber diaphragm inside the neck of the bottle which keeps the water in (under pressure from the air). All Adam has to do is stick a wire in the valve and off Action Man goes. The vehicle crashes nicely into a garage door and the wheels fly off. Adam looks queasy but is assured that the wheels on his machine are not made of flower pot saucers as these are.

It is now or never. Adam puts his new helmet on and then tries to get it off. Director Paul, nervous about the failing light situation, tells him it is easy - all you do is release the red button on the side.

Just press red, Adam Adam has trouble looking down through his face to see the button as his chin is in the way. He tries to 'feel' the red but maybe this will one day be possible - to feel colour as opposed to seeing it.

In the gloomy evening light Adam at last powers his bicycle along the Rockingham Motor Race track and into the record books (we are writing them this very minute).

He manages to cycle his inordinately heavy four wheeled bicycle to around 10 mph, then releases the water jet. The G force is tremendously absent as Adam is boosted an extra 10 mph, powering him on - to a staggering 21 mph.





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