Recycling in a cold climate
an experiment with a 'Cycle Ski'
Pedal Power Overview
There are six and a half billion souls on this planet and counting. There are not enough materials and energy for everyone to live as the developed world does now and many agree that we need to change our habits.
One of the biggest problems is the automobile. It not only pollutes but is believed to contribute to climate change. Many of the alternatives now being proposed, like electric cars, merely transfer the problem from road to power station. A popular saying from over forty years ago puts it in a nutshell :
Everything is connected to everything else
Everything has got to go somewhere
There is no such thing as a free lunch
Everything has got to go somewhere
There is no such thing as a free lunch
In the third world bicycles are a vital means of transport. In the developed they are used mostly for sport and fitness . However there are many, including the writer, who believe that the re-introduction of cycling would benefit society. People would be healthier and the death of local community might be arrested.
Pedalling is the most efficient way ever devised for people to produce sustained power. But is the ordinary bicycle the best way of using this power?
the HPV
The
biggest problem for a vehicle moving at speed is air resistance, which
is why streamlining is employed..
The upright bicycle has a large frontal area but by lying down in the
'recumbent' position this area is reduced and the machine is
easier to pedal. This was demonstrated in 1933 by Francis Faure
breaking the world speed record. (Unfortunately the World Cycle
Union then banned recumbents from competing and this set back development).
Things got going again in the seventies and today there is a wide selection available of tested vehicles. Some builders put fairings on their machines to make them go even faster : the current world speed record is 82 MPH.
The
idea of pedalling extended to other forms of transport. It was found
that boats could be pedalled twice as fast as they could be rowed - in
fact fast enough to rise up on hydrofoils. Some boats have been
pedalled over the Atlantic. Others constructed aeroplanes, to show that
humans really could fly. Since most, but not all, of these vehicles use pedalling
exclusively they are usually referred to as 'human powered vehicles' or
HPV's.
It is well known by anyone who has ever ridden one that upright tricycles are not stable because the centre of gravity is too high and the rider cannot lean into corners as on a bicycle. The recumbent tricycle reduces these problems considerably. There are two configurations : 'tadpole' with two wheels at the front, and 'delta', with two wheels at the back;
In addition to these mainstrean recumbents many other
designs and combinations will be found on the net : front
wheel drive, tilting trikes, and the 'sociable'. Many build their own
machines , often using recycled parts.
Things got going again in the seventies and today there is a wide selection available of tested vehicles. Some builders put fairings on their machines to make them go even faster : the current world speed record is 82 MPH.
the Recumbent
Like most things the design of a recumbent is a trade off. In the case of a bicycle the front wheel has to miss the pedals : either putting it in front, thus producing a long wheelbase (lwb) suitable for cruising; or putting it under the knees, the short wheelbase (swb) being better adapted to nipping around congested areas.It is well known by anyone who has ever ridden one that upright tricycles are not stable because the centre of gravity is too high and the rider cannot lean into corners as on a bicycle. The recumbent tricycle reduces these problems considerably. There are two configurations : 'tadpole' with two wheels at the front, and 'delta', with two wheels at the back;
Ice and Snow
A
cold climate presents a variety of surface conditions. Cycling through
wet snow is like cycling through mud. Cycling on ice requires
knobbly tyres or studs. Nevertheless winter cycling is alive and
well and some enthusiasts race on ice.
The idea of the 'ice bike' goes back a long way and many patents have been taken out on a variety of spiked tyres or studded belts :
However not much attention seems to have been paid to skis and I wondered why not. I lashed a pair of skis to the front of a bike and found that I could push myself along OK, even though most of the weight fell on the back wheel. But the upright bike provided no convenient point of attachment for the skis to be mounted further back. So I decided to make a lwb recumbent for further experiment.
Anticipating that some form of steering would be necessary, I also experimented with flexible linkages. Finally handlebars were made adjustable in the fore and aft direction to accomodate alterations in the vehicle's centre of gravity :
Normally February is the coldest time of the year and there is thick layer of snow and ice here. This year February has been very strange and as I write spring flowers are emerging. Without carting this contraption further north there was a single window of opportunity to test it before the brief snowfall melted. A very brief clip of the test is here :
I had intended to experiment further but it looks like my chances are limited this winter. These are the things that can be improved :
1) the main problem is drive. The wheel I used was too small and not 'knobbly' enough : some form of belt, or lightweight drum mimicking ski poles, would seem to be a better alternative. Then the driver's weight could be placed more nearly over the centre of the skis.
2) the steering arrangement needs to be properly worked out. Ski poles/'handlebars' can themselves be used for serious braking by thrusting them into the snow.
3) the skis I used are too small for soft snow conditions. Today in Finland most people ski in tracks for fitness and the width of modern skis has shrunk to 4 cm. But the remains of skis (some of them thousands of years old) have been excavated which are very much larger : some of them three metres in length and 14 cm. wide made from birch or pine, evidently to handle virgin snow. The 'snowshoe ' below from 420 BC gives an idea how delicate these things were :
It is interesting to speculate what a properly designed pedal-powered, lightweight, vehicle using such skis might be capable of. Perhaps others might be interested in experimenting further? ( I should think that kids might like the idea.)
The idea of the 'ice bike' goes back a long way and many patents have been taken out on a variety of spiked tyres or studded belts :
However not much attention seems to have been paid to skis and I wondered why not. I lashed a pair of skis to the front of a bike and found that I could push myself along OK, even though most of the weight fell on the back wheel. But the upright bike provided no convenient point of attachment for the skis to be mounted further back. So I decided to make a lwb recumbent for further experiment.
Home building
In line with the philosophy of re-cycling I cut up a kids mountain bike. Normally brazing is considered the best route for a home builder, but I found myself in a small but clean flat with few tools, so I used pine, glassfibre, and epoxy to make a beam connecting the headset and rear triangle. It is a very easy method. I used an old camping chair for the seat.Anticipating that some form of steering would be necessary, I also experimented with flexible linkages. Finally handlebars were made adjustable in the fore and aft direction to accomodate alterations in the vehicle's centre of gravity :
Conclusions
Normally February is the coldest time of the year and there is thick layer of snow and ice here. This year February has been very strange and as I write spring flowers are emerging. Without carting this contraption further north there was a single window of opportunity to test it before the brief snowfall melted. A very brief clip of the test is here :
I had intended to experiment further but it looks like my chances are limited this winter. These are the things that can be improved :
1) the main problem is drive. The wheel I used was too small and not 'knobbly' enough : some form of belt, or lightweight drum mimicking ski poles, would seem to be a better alternative. Then the driver's weight could be placed more nearly over the centre of the skis.
2) the steering arrangement needs to be properly worked out. Ski poles/'handlebars' can themselves be used for serious braking by thrusting them into the snow.
3) the skis I used are too small for soft snow conditions. Today in Finland most people ski in tracks for fitness and the width of modern skis has shrunk to 4 cm. But the remains of skis (some of them thousands of years old) have been excavated which are very much larger : some of them three metres in length and 14 cm. wide made from birch or pine, evidently to handle virgin snow. The 'snowshoe ' below from 420 BC gives an idea how delicate these things were :
It is interesting to speculate what a properly designed pedal-powered, lightweight, vehicle using such skis might be capable of. Perhaps others might be interested in experimenting further? ( I should think that kids might like the idea.)