Development of Bicycle as a form of Personal & Public Transport

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Abstract

Personal and Public Transport includes skate boards, skis, bicycles, motor vehicles, boats, motor cycles, buses, trams, trains and airplanes. Over centuries there have been significant developments in the design, materials technology and process of engineering in all forms of personal and public transport.

This report investigates and documents significant developments in bicycle design and technology.

The first part of the report illustrates and describes developments of bicycles from hobby horse to RMIT Superbike. It analyses the mechanical advances and provides an analysis of significant developments in material technology and how this developments provide improvements in overall efficiency of the bicycle associated with each development.

The second part investigates the environmental and the social impact which led to the evolution of bicycle design and the growth of recreational cycling.

Introduction

Macquarie dictionary defines bicycles as “a vehicle with two wheels, one in front of the other steered by handlebars and driven by pedals”.

Bicycles were invented at the same time as the steam power and rail transport were being developed. The bicycle represented the first machine to be mass-produced for personal transport.

The first bicycle is considered to have being developed in France towards the end of the eighteenth century. Initial pioneer models consisted of a simple frame of little more than a wooden beam connecting two wheels front and back.

Historically the designs of bicycles depended on the function of the bike, the nature of obstacles in which it is going to endure and the available material technology at that point in time.

This report will investigate and document significant historical developments in bicycle design and technology. It will detail a clear and accurate timeline of bicycle design and development.

This report will clearly identify a range of significant developments in materials technology with a detailed analysis of the social and environmental impacts of bicycle as transportation, recreation and sporting vehicles.

Today with the wide range of materials and manufacturing processes available bicycle design and materials can be closely matched to the intended user terrain and price expectations.

Most bicycle designs were dictated by considerations such as:

· Weight

· Strength

· Bending resistance

· Toughness

· Fatigue Resistance

· Corrosion Resistance

· Cost

· Production

· Ethics

The basic requirements however remain that the bicycle must be light enough to be lifted or carried when required and strong enough for the conditions of use.  

Before most modern advancements, materials used for bicycles included mainly timber, iron and steel. More recently aluminum alloys, polymers and composite materials are being used for the elements of bicycle design.

Evolution of Bicycle DesignDevelopment in bicycle design, through mechanical advances & material technology

As far back as 1490 to 1863

As far back as 1490, Leonardo da Vinci had envisioned a machine remarkably similar to the modern bicycle. Unfortunately, da Vinci did not attempt to build the vehicle, nor were his sketches discovered until the 1960’s.

In I790 the 'célérifère' or 'horse on wheels' was introduced. It had no steering and was powered by pushing against the ground with the feet. The engineering design was very basic, used manual foot power to propel and the material was primitive wood.

In 1818 Draise von Sauerbronn modified the célérifère by incorporating springs beneath the seat to soften the ride and added a handle bar to the front wheel to improve steering The new machine became known as the 'Draisine' also known as the hobbyhorse. It was the first bicycle which featured steering and comprised a wooden frame and wheels. It proved that a person riding it could keep balance while the bike was in motion. The engineering design lead to the bicycle being able to be steered and made it lighter with an increase of robustness.

1840 was the year when Kirkpatrick Macmillan added treadles to the rear wheel of his hobby horse. They were operated by rods connected to foot stirrups. To propel the bicycle the foot straps where pushed backwards and forwards. Unfortunately his ideas did not catch on.

First pedal powered bicycle

1863 to 1873

In 1863 Pierre and Ernest Michaux introduced the 'Vélocipède' fast foot also known as the 'bone shaker' due to its rather painful ride. This machine was important in that it signified the first commercially practical bicycle and introduced a pedal system attached straight to the front wheel hub. The bicycle frame was still made of wood but protective iron tyres were attached to the wooden rim. One rotation of the pedals resulted in one rotation of the wheel. 

In order to travel further with each rotation of the pedals a larger front wheel had to be fitted. This solution concluded in 1870 with the 'Penny-farthing' invented by James Starley. The very large front wheel allowed an increase in the distance covered per turn of the pedal. The large wheel provided another benefit that it immersed a lot more shock than the old ‘boneshaker’. This was achieved by solid rubber tyres and thin wrought iron spokes. As shown in the picture:

1873 to 1980

In 1873 the Englishman H.J. Lawson developed a chain and sprocket system that allowed the pedals to be placed between the two wheels rather than being attached directly to the front wheel hub. With the invention of the chain and sprocket the size of the front wheel was no longer important as speed could be determined instead by the size of the sprocket.  

Starley replaced the radial arrangement of spokes in 1874 with the semi-tangential design common today in order to redistribute loads around the other spokes and brace the wheel against torque when accelerating and decelerating.

The high torque developed by the pedal on the hub however initially resulted in fractured spokes. The radial arrangement of spokes originating from the wagon wheel construction resulted in the bottom spoke being heavily loaded in compression.

From this, the spokes were then designed to be in tension which resulted in the semi-tangential bicycle spokes. This fixed the problem of the bottom spoke being heavily loaded in compression, because if they wheel were to go into compression it would have to cancel out the tension in the spoke.

1877 was the year when steel tube and diamond frame construction was introduced. This was because the frame was solid metal which contributed to its enormous weight. Through much experimentation a hollow metal circular tube was discovered which offered strength with reduced weight.

Also in this period ball bearings were developed, they were introduced because of the friction the penny – farthing caused by the wheel hub rotating on the axle. The contact resulted in the surface to wear. Ball bearings prevented friction which resulted in smoother rotations and longer life of the axle. It also increased mechanical efficiency causing it to rotate much more smoothly.

1884 was the end of era of high-wheeled bicycles when John Starley produced the Rover safety bike. It is considered the prototype of the modern day bicycle because it had many of the features still seen on bicycles today. Having a large chain ring and a smaller rear sprocket meant that a velocity ratio similar to that of the ordinaries was achievable. It was easier to mount and dismount and it was much safer to ride. The chain and sprocket was made possible by developing steel technology of the time, which allowed small parts to be manufactured without giving up strength. The rover and other safety bicycles also saw the introduction of the pneumatic tyre.

By 1888 pneumatic tyres had been introduced followed shortly afterwards by the tubeless tyre. Pneumatic tyres revolutionized bike riding. Prior to their invention all tyres where made out of solid rubber. The pneumatic tyre was filled with air. The air inside these tyres absorbs a lot of shock; hence they made bicycles much more comfortable and allowed faster speeds to be reached.

As a result of the major advances already discovered, up to 1950 there was a decline in support, improvements and the manufacture of the bicycle. There was little to none gradual refinements of the standard bike design. Bicycle riding as a sport delivered the need for new materials and designs e.g. light aluminum alloys, carbon fibre, titanium alloy etc.

Around the 1970 people saw the introduction of the BMX bicycle and new design & material technology advances such as chrome-molybdenum frames and ABS spokes and rims. Chrome-molybdenum frames were used because it had:

· High resistant to fatigue and bending

· Easily can be welded

· Good strength

· Good corrosion resistance for steel

1980 was the period in which the first mountain bike was introduced. Due to the components failing under increased stresses of rough riding, frames became thicker and heavier to improve the overall strength of the bicycle. Early designed mountain bikes were weighed around 20kg, but improving materials technology reduced the weight of a modern bicycle to about 12kg. This new innovation led to improvements in:

· Carbon fibre frames, used because of its extremely light weight, rust resistance , shock absorption, easily molded, good strength

· complex suspension systems, (better riding comfort)

· disk brakes, (improved efficiency)

· gearing systems (improved mechanical efficiency for the rider)

· Kevlar reinforced tyres (stronger than normal tyres)

Present – 21st Century

With a larger part of the population taking up bicycle transportation dedicated roads lanes were developed to accommodate the demands of cyclists for a smoother and safe ride.

Today in the 21st century, a vast range of different designs and materials had led to bicycles being used for more specific purposes. They are now being as a form of utility and racing purposes.

Utility bicycles are used for

· Bicycle touring

· Mountain biking

· BMX

· Physical fitness

· Transportation

· Recreation

The range of materials used for recreational bikes are not as significant as the improvements in materials present on transportation or racing purposes. These bikes use aluminum alloys, because it is cheaper than other materials, rider comfort is high & outperforms in strength, bending and corrosion resistance. Aerodynamics was not a big factor compared to the RMIT superbike.

Racing bikes such as the RMIT superbike uses unique material which allow it to be very light weight with high strength. It had to achieve goals of:

· Optimizing weight

· Frame stiffness

· Aerodynamics

The bicycle was designed to have a carbon fibre – polymer hollow monocoque which was shaped to reduce aerodynamic drag. This was done so the bike had lower weight and greater stiffness. Compared to modern day bicycles which weigh around 12kg, the superbike is 7kg lighter; weighing at 5kg. This was the advantage of using carbon fibre. Its properties mean that it has a very low weight and a very high bending resistance. It was the ultimate material as the track is not bumpy (absorbs minimal shock) and there are no obstacles (could easily snap).

Carbon fibre was the chosen material because it had:

· No fatigue or rust

· Was extremely light

· Easily molded into intricate shapes

· Good strength and shock absorption which can be controlled

However, it was not implemented into recreational bicycles because:

· It was extremely expensive

· If the material failed it would fail catastrophically

· It is a waste of material if designed poorly because it is not recyclable

Environmental & Social Impact

History of Personal and Public Transport is closely related to the development of modern society. As transportation increased in capacity and efficiency the barriers to trade, communications between villages and nations were reduced. Reliable means of transportation brought vast changes to the performance of commerce trade, social and cultural perceptions.

The development and evolution of personal and public transport have impacted the environment and society. The invention and evolution of bicycles have had positive and negative influences on the environment and society.

Environmental

Cycling is often looked on as one of the many solutions to environmental problems, such as pollution and the greenhouse effect. However issues of pollution and greenhouse effect have been contributed by enhancement of industrial process and use of energy to design and invention of new material and technology.

This includes search of new materials to produce improved bicycles. Initial designs used timber and use of timber at industrial level resulted in the clearing of large areas of forest. This had negative effects on native flora and fauna and their habitat.

Later designs included steel, cast iron and aluminum. The minerals mined from the earth require establishment of large steelworks, which often affect the local atmosphere with the large amount of pollutants produced in working and refining metal.

Aluminum was best when bicycles needed to be lighter for efficiency. The earlier mining of aluminum ore - bauxite was from open cut mine. These types of mines contributed to mass land clearing, water pollution, human activity, new towns and settlements and all these contributed negatively to the local atmosphere and environment.

The present day bicycles use polymers, alloys and composite. These products use chemical engineering process. The products use made bicycles easier and lighter for racing, touring, recreational etc. Its usage has exploded, because polymers offer lightweight properties which improve the stiffness and the weight. However polymers can greatly contribute to the landfills.

Different materials had their distinct contribution is the development of private and public transport like bicycles.

Cycling, as a form of transport, is one of the most efficient ways to travel: that is: the energy is used more usefully than many other forms of transport. It is non-polluting. It is non-polluting and human power is a renewable energy source.

Use of bicycles have positive contribution to the environment and it mitigates the greater environmental issues contributed by industrialized process.

Social

The early years of the 20th century saw an expansion of industrial uses for bicycles. These included work cycles used as military vehicles, ambulances and transportation for police, doctors and for local deliveries, hauling and mining.

A variety of new work cycles came into production for industrial uses. Socially the bicycle helped to strengthen the jobs for rural workers. With bicycles, workers could commute to work from triple the distances that they were accustomed to before. Employers courted workers from longer distances and made rural workers a viable labor pool for cities as it both fostered urbanization.

They helped reduce people’s dependence on horses and allowed people to travel to the country. Bicycles were three times as efficient as walking and three to four times as fast.

A number of tricycle designs were introduced. These were particularly popular with female cyclists to the extent that the increased freedom afforded by the bicycle. This has been associated with the beginnings of the women's movement for political and economic equality.  This gave women mobility and contributed to their freedom.

Due to this the craze for cycling amongst women created a whole new set of fashions including a dress which is a cross between a skirt and trousers pants. The new dress helped free women from the corset and other restrictive clothing. Women's access to their own personal transportation also meant they did not have to depend on men or horses for local mobility. 

Towards the ending of the 19th century in Europe and United states, bicycles served as personal transport for the wealthy. They offered interdependence and were less troublesome than the horse and buggy. However they were not widely adapted due to safety and expense.

Racing has been a social activity associated with bicycles from their inception. The Draisiene running machine was a gentlemen's toy designed to allow riders to speed it achieved speeds of 7 to 9 miles per hour which considerably higher than normal walking speed. These speeds could not be maintained for any length of time or on uneven terrain. In turn cycle racing simultaneously was a spectacle, a community and a business. Famous racers such as the LeTour de France symbolize the social power and influence of bicycle racing. At the turn of the 20th century numerous velodromes were built in the US and Europe to accommodate cycle racing.

In developing countries the bicycle still remains a primary mean of personal transport. The image of Asian cities clogged with bicycles is a common image, but may be short lived. As the counties become wealthier their citizens prefer cars for transportation. To cope with theft, many destinations provide bike racks.

Since the 1980s interest in bicycles has gradually returned to mostly as a fitness group activity, hobby and competitive sport. Specialized sports such as Mountain biking, BMX, Bicycle touring have emerged.

Conclusion

Bicycle materials and construction have evolved with time with significant developments in bicycle design and technology. The design of bicycles had been motivated by the nature of obstacles in which it is going to endure and the available material technology at that point in time.

The range of variations available in materials, components, design and cost are all seen today allowing modern bicycles to suit the need and preferences of many people today. The old bicycles like modern bicycles designs were needed to overcome obstacles.

Significant major social impacts have led to different designs of the bicycle (tricycle), which particularly gave women mobility, contributed to their freedom and created a whole new set of fashions. Environmental impacts have also changed designs with different choices of materials which shaped the bicycle.

Bicycles will continue to evolve with major improvements due to social and environmental impact which will also shape the advancement of materials and mechanical efficiency.

References

· School Engineering Text book

· http://en.wikipedia.org/wiki/Wheelbuilding

· http://en.wikipedia.org/wiki/Safety_bicycle

· http://hfboards.hockeysfuture.com/showthread.php?t=774571

· http://www.flickr.com/photos/cstmweb/3322870427/

· http://www.powerhousemuseum.com/hsc/bike/features.htm#

· http://en.wikipedia.org/wiki/Mountain_biking

· http://wiki.answers.com/Q/What_are_bicycles_used_for

· http://reynoldstechnology.biz/our_materials_7005.php

· http://bicycledesign.net/

· Personal & Public Transport – TAFE

· http://eslbee.com/why_people_should_ride_a_bicycle_for_short_distance_trips.htm

· http://www.madehow.com/Volume-2/Bicycle.html#b

· http://www.springwise.com/health_wellbeing/bicycle-design-mobile-riders/

· http://elev8bikes.com/

· http://www.answers.com/topic/bicycle-shorts

Raajit Sharma12EST