The Wheel

The wheel is one of the world’s most important inventions. It is the key to motion and plays a huge part in society today. Present everywhere on all our cars, trains, ships, planes, machines, and wagons; wheels play an integral role in industrial technologies and consumer products. Their rolling motion is the basis of many mechanisms such as pulleys, gears, cams, and bearings. Wheels are one of the oldest technologies, with roots around since the beginnings of recorded history.

Throughout time, wheels have evolved. Around about 3500 BCE, wheels were wooden disks, developed from the use of logs as rollers. Spokes were introduced in 2000 BCE, as they considerably reduced the wheel’s weight assisting better motion. They also gave it a resilience that ‘cushioned’ travel over rough terrain.

19^th century wagon wheel production has been of great interest to me recently. Wheelwrights created functional works of art from raw materials like wood and iron, having only experience to rely on; no books or education. Formal procedures of modern engineering such as materials selection, stress analysis and fracture mechanics, were carried out intuitively. The hub, spokes and felloes (sections of the rim) were shaped using the simplest of hand tools. Each spoke was hammered into a felloe and hub, without the use of bolts, screws or glue.

Many aspects of the wheel were thought through to make it suitable for purpose. Firstly, each of the wheel’s components required wood with specific properties. For example, ash, beech, or elm would be preferred for the rim, because of their flexibility and toughness, so the rim would be easy to shape as well as able to withstand the harsh conditions it would be put through. Secondly, large diameter wheels reduced the force required to pull the wagon. Thirdly, the wheels were dished, with the top of the dish facing outward from the wagon. This has shown to increase the wheel’s strength toward lateral forces, so the wagon could resist the effect of any side-to-side motion. If the wheel were perfectly flat, this motion would tend to bend and finally break the spokes. The outward slant also allowed the wagon body to be tapered outward, increasing its load-carrying capacity.

I have been reading ‘Masterworks of Technology’ by E. E. Lewis and would recommend it to everyone with an interest in engineering.

Flying Cars

Our idea of the future is a world full of astounding technology, remarkable engineering defeats, and overwhelming sky scrapers. If you look at how far the world has come over the past 10 years, to be completely honest, the landscape hasn’t changed an awful lot. The reason for this isn’t that technology, knowledge and expertise haven’t progressed, but that we aren’t daring enough to make any significant changes. Industries like the media exaggerate everything, making everything a public issue, when really many things are best left to the experts. For example, when The Large Hadron Collider was launched, the world was in a state of panic. The rumour was we were all going to die through the formation of a black hole, as a result of this experiment. We are too scared to move forward and explore and implement new ideas, because we are too afraid of the possible consequences. Safety regulations have almost grown into an obstruction against innovation and new inventions.

One of the main components of the image we have of our future world is flying cars. Made popular by Hollywood movies such as The Fifth Element, we predict the air to carry our mass transport in forthcoming years. The truth is, the technology and knowledge on how to build a flying car, is already here. Inventors have already developed the first flying car and it is already possible to make this a reality. However, could you really every imagine it being given consent? It would breach every safety, security, protection, and public welfare regulation there is. We are too afraid to materialise our future.

Called the ‘Terrafugia Transition’ and developed by former Nasa engineers, it can transform itself from a two-seater road car to a plane in 15 seconds. Powered by the same 100bhp engine on the ground and in the air, it will be able to fly up to 500 miles on a single tank of petrol at a speed of 115mph. It has the capability to solve problems such as congestion and traffic jams, and revolutionise the world we live in. We need to expand our transportation systems fast enough to meet our increasing demands.

The Large Hadron Collider

All particles in the universe fall into two categories: Hadrons and Leptons. Leptons are fundamental particles including electrons, heavier muons, and very hard to detect neutrinos. Hadrons consist of quarks, which are subatomic particles carrying a fractional electric charge. They are split into two groups – Mesons and Baryons. Protons and neutrons are both baryons. Mesons can be Pions or Kaons.

Every particle has an antiparticle. For example, the antiparticle of a Proton is an Antiproton. When a particle meets its antiparticle, they annihilate one another, producing two photons of energy in the opposite directions to conserve momentum. These photons of energy can also change into a particle-antiparticle, during Pair production, if they have enough energy. Alternatively, electromagnetic waves are emitted when a charged particle loses energy, by being stopped, slowed down or made to change direction.

When two hadrons collide, they interact through the strong interaction, converting their rest energy and kinetic energy into new particles with the same amount of rest and kinetic energy in total. Energy, momentum, strangeness, baryon number, and lepton number, are all conserved in the reaction.

The Large Hadron Collider works on these basic principles. It allows us to discover more about particles and answer the fundamental questions of science. Located near Geneva, part of the European scientific Research base Cern, it is the biggest accelerator in the world. It has a ring shape and circumference of 27 kilometres, at a depth ranging from 50 to 175 metres underground. With a budget of £ 6.19 billion, it is one of the most expensive scientific instruments ever to be built.

It works by accelerating charged particles, boosting their kinetic energy at several places, to energies of more than 7000GeV. There are magnets to bend the path of the particles to keep them in the ring. Researchers hope that the data gathered by smashing particle beams together at ultra-high speed will help to solve questions about relativity, natural forces and dark matter.

Suspension Bridges

Suspension bridges are beautiful. Situated in the biggest cities in the world, a thriving city’s mass traffic often depends on them. This is a huge responsibility, considering you’d expect them to have low stability. The Pearl Bridge, in Japan, has the longest span of any suspension bridge, at 6529 feet.

They fascinate me because of their simplicity and the little support they rely on. The first suspension bridges were simpler, without vertical suspenders. This type of bridge is still considered the most efficient and sustainable design in developing countries.  They are common in mountainous areas, and to cross shorter spanned rivers. It has an arc shape, due to the simpler concept, which gives it many limitations. One of the main things is that it restricts the capacity of load that can be carried.

 A suspension bridge today in developed countries over longer spans and with more challenging requirements, has two tall towers, through which cables are strung. A deck is suspended from these cables, so the towers are therefore supporting the majority of the roadway's weight. The main forces are the tension in the cables and compression in the pillars. A supporting truss system beneath the bridge deck helps to stiffen the deck and reduce the tendency of the roadway to sway and ripple. A suspension bridge allows longer spans to be achieved than with any other type of bridge, requiring less material.

New York is one of my favourite cities in the world, and amongst many of its engineering defeats, is the Brooklyn Bridge. The bridge carries an average of 145,000 vehicles per day. The construction of the Brooklyn Bridge started in 1869 and took 14 years to complete.

Space Elevator

One of my favourite quotes in the world:

"My journey to the stars, among the stars, at one with the stars, was a place of absolute contentment, the most peaceful existence I have ever known. And the most powerful, for in that state of oneness with the universe around me, I stood as a god." - Drizzt Do'Urden (R.A Salvatore)

If I had to pick my deepest desire, it would be to travel space. To feel the breathtaking feeling of no gravity. To escape the spin of the earth and truly be still. To look out from space, into space, and wonder at its infinity. I can't imagine anything greater. Dreamt of being an astronaut since I was 6 years old, when I first learnt the order of the planets in our solar system, as well as the name of the closest star to us other than the Sun, Proxima Centauri. Since then, the cosmos has been my biggest curiosity.

Therefore, something that really inspired me was a lecture on BBC4 from the Royal Institution – ‘Can We Build an Elevator to Space?’  Materials scientist Dr Mark Miodownik, discussed the possibilities of making space travel available to the mass audience. After considering many ideas, such as an extension of a sky scraper, the stability of a pyramid, and the impracticality of a staircase, the answer became clear. Instead of building upwards, to escape gravity, we should use it to our benefit. A satellite could be sent out into space, which would reel down the cable for an elevator.

144,000 miles of cable would be required, and the cable would extend 22,000 miles above the Earth to a station, which is the distance at which satellites remain in geostationary orbit. Due to the competing forces of the Earth's gravity and outward centrifugal pull, the elevator station would remain at that distance like a satellite. Then the cable would extend another 40,000 miles into space to a weighted structure for stability. An elevator car would be attached to the nanotube cable and powered into space along the track.

The best material produced to date, to suit such a mission, is Carbon Nanotubes. These have been constructed with length-to-diameter ratio of up to 132,000,000:1 – significantly larger than any other material. It also has great tensile strength, durability and many other exceptional properties. Each atom is joined to three neighbours, as in graphite. The tubes can therefore be considered as rolled-up single layers of graphite.

Have a look at this:

http://www.dvdbrowser.co.uk/index.php/2010/12/build-elevator-space-royal-institution-christmas-lecture-2010-bbc/

Transatlantic Tunnel

I always find episodes of ‘Extreme Engineering’ on Discovery and Quest, a worthwhile watch. Their documentaries are usually thought-provoking, interesting, and the use ‘Extreme’ is surely well used. The challenges of designing and building outrageous and awe-inspiring projects are shown, along with computer animations of the structures, allowing the viewer to better understand what’s going on. They follow the efforts of engineers and scientists taking on these seemingly impossible projects.

One of the ventures that really stuck in my mind, was the idea of building a Transatlantic tunnel. The Atlantic Ocean is the second largest ocean, with an average depth of 3926metres. The tunnel is to be built connecting Europe to North America, covering a distance of 3,100miles. Scientists and engineers have proposed many theories to overcome the colossal challenges this offers. Firstly, the depth and mass of water are too large for a standard bridge type structure to be built holding the tunnel in place, as divers wouldn’t be able to build that deep. Also, the sea floor isn’t always level, so it wouldn’t be very steady. But most of all, the amount of resources required would be ridiculously unfeasible.

Therefore, the best idea put forward to date is a floating tunnel anchored to the seafloor with tethers, powered by electricity. This would deal with the strong sea currents, as it would give the tunnel the ability to sway slightly under pressure. 150ft below the surface, it can avoid ships and still escape the highest points of pressure. The tunnel will be built with 54000 prefabricated sections connected by watertight and vacuum-tight gaskets, which would take decades to complete. Each section’s outer skin would be constructed of stainless steel, followed by a thick layer of super-buoyant foam. The train will have to travel at a colossal speed, 20 times the speed of today’s fastest trains. For this to work, the train will be magnetically suspended an inch off the track. Magnets will lift, guide and propel the train, instead of wheels and rails. To travel at such a speed, the train cannot cope with air resistance, so a vacuum will have to be maintained inside the tunnel.

It would be a breathtaking experience for commuters. The tunnel will have a window, providing passengers with a brief view of the ocean. To cope with the magnetic field and gravity at the same time, passengers will sit on pivoting, rotating seats. That sounds exciting. I think it’s obvious that this journey won’t feel like your everyday train journey. And rightly so, as the project would cost $175 billion to $12 trillion, which is the main barrier against constructing such a tunnel.

Have a look at this:
http://video.google.com/videoplay?docid=-6734188128065094941#