Wednesday, August 21, 2013

Another Dimension In Printing: 3 D Printing Technology



Just when you feel contented and think that this is the end of it, the scientists and technologists surprise you with something even more bizarre, revolutionary idea which ultimately takes you back to think – “Yes.. this was remaining”. Consider any technological innovation or scientific theory, and you will be amazed to find out that how the idea progressed, fueled by radical thoughts, to keep on shaping up and re-shaping the future. In this post, we’ll discuss about one such idea which has the potential to turn around things spanning over innumerable areas that we come across in our daily lives.

Until now we believed that printing could only be done in 2-D. But, as usual, we were proven wrong by the innovative minds. Imagine, you want to get a showpiece model of your favourite Audi R8 with the minutest of details. What would you do? Just walk into your room, upload the digital car model into your printer and the job is done. Yes, the output would be a 3-D model. Sounds somewhat like Star Trek Replicator right? Well this has been made possible by 3-D printing technology which is making it easier and faster to produce complex objects with multiple moving parts and intricate design in an impeccable manner.

How Does a 3-D Printer Work?

By now you must be curious to further explore the processes behind 3-D printing technology. So let us understand the science behind it. Additive manufacturing, which means creating an object by adding material to the object layer by layer, is the family of manufacturing technology that includes 3-D printing. It’s much like printing in two dimensions on a sheet of paper, but with an added third dimension. Each of these printed layers is a thinly-sliced, horizontal cross-section of the eventual object. Imagine a pizza maker is laying down one thin layer at a time until the entire pizza is formed. The process is somewhat similar.

In order to perform its function, a 3D printer needs to have a Computer Aided Design (CAD) file, which is created using 3D modelling program, and instructions for what to print. The created a file that is sent to the 3D printer. Along the way, the program slices the design into thousands of digital cross sections for the machine. To perform print function, the machine reads the design and lays down successive layers of liquid, powder, paper or sheet material to build the 3D model from a series of cross sections. These layers are joined or automatically fused to create the final shape.

Applications

 

Miniature human organs has been created using 3D printing technology which would enable better and realistic drug testing ground for understanding the reaction of human body to dangerous diseases, chemical warfare agents and new drugs. The intention is to defend against biological or chemical attacks. These tiny organs represent small groups of human tissue of these organs connected together by a system of fluid channels that circulate blood substitute to keep the cells alive. This means that researchers can introduce biological or chemical agents into the blood substitute to see how it affects the different organs.

 

 

A 3D food printer is up and running at the French Culinary Institute in Manhattan and if experts are to be believed, it would be at your home in next 5 yrs.!! A group of scientists and students at Cornell University built a 3D printer and began testing it out with food. The printer's syringes were loaded up with raw liquid food, such as soft chocolate, and ingredient-filled syringes will then "print" the shape that you want depending upon the description of how that shape can be made and how the material that you want to print with works.

   

Chinese scientists have successfully printed ears, livers and kidneys, with living tissue using this technology using specialized 3D bio printers that use living cells instead of plastic. According to the research team, the printer takes less than an hour to produce either a mini liver sample or a four to five inch ear cartilage sample. It has also been predicted that fully functional printed organs may be possible within the next ten to twenty years.


NASA has successfully created 3D-printed parts for rocket engines. One of these is the largest 3D-printed rocket part built to date, a rocket engine injector, which has survived a major hot-fire test. The injector generated 10 times more thrust than any injector made by 3D printing before. Also, 3D printing can reduce the number of parts needed to build a rocket engine. The injector in this test, for example, was made in two parts, while a similar injector from earlier tests had 115 parts.



Future of 3-D Printing Technology

 

By now you must have realized how disruptive 3D printing technology is. If pushed ahead properly, it would have positive effects on energy usage, waste, customization, product availability, medicine, construction, the sciences, manufacturing and many more industries. It will change the world as we know it.

 

Wednesday, August 7, 2013

The String Theory: Another Dimension In Particle Physics


So, you are walking down the street, enjoying your ice cream and suddenly your friend tells you that everything in this world is made up of strings!! You will probably brush aside his argument at that point of time, but it still makes you think. Can we actually be made up of strings? On a broader perspective, we live in a complex universe and we have wondered time and again – what is the universe made up of? When would it end? Where did we come from?

The String Theory is touted as the most recent attempt to answer the first question. If you ask an elementary science teacher at school, her terse answer would be ‘atoms’ (which, by the way, is derived from the word ‘atomos’ that means ‘uncut’). As you move up the division, you will be given a more technical and more convincing answer that the atom can be divided and elementary particles are electrons, protons and neutrons. Most of the times that is the extent of it. Very few people go beyond this explanation to explore more. So, in order to understand what string theory suggests, we will first discuss the standard model of particle physics.

The Standard Model of Particle Physics

Standard Model describes the fundamental building blocks out of which the world is made, and the forces of interaction between these blocks. There are 12 basic particles, six of which are quarks - up, down, charm, strange, bottom and top. So, a proton, for instance, is made of two up quarks and one down quark. The other six are leptons which include the electron, its two heavier siblings, the muon and the tauon, and three neutrinos.


The four fundamental forces in the universe are gravity, electromagnetism, and the weak and strong nuclear forces. Each of these is produced by fundamental particles that act as carriers of the force. The most familiar of these is the photon, a particle of light, which is the mediator of electromagnetic forces. What does that mean? Well it means that, for instance, a magnet attracts a nail because both objects exchange photons. The graviton is the particle associated with gravity. The strong force is carried by eight particles known as gluons. Finally, the weak force is transmitted by three particles, the W+, the W- , and the Z.

Standard Model describes the behavior of all of these particles and forces in an impeccable manner. Though there exists a notable exception: gravity. The gravitational force has proven to be very difficult to describe due to technical constraints. Here is when string theory comes into the picture which attempts to provide a unified and complete theory of structure of the universe – ‘The Theory of Everything’.

The String Theory

So, what exactly is string theory you must be wondering. The string theory suggests that all the fundamental particles are nothing but different manifestations of a single object – a string. Sounds very unconvincing right? Imagine a guitar. Depending upon the tension in the guitar strings and the way they are plucked, different musical notes can be created by the same set of strings. Similarly, consider an electron. It is just a point with no internal structure. According to string theory, when observed under a very powerful microscope, we would notice that it is not really a point – it is a loop of string and the length of the string is to the order of 10-33cms.!! And this string could oscillate in different ways and it does that so fast, that it would be seen as a point from a distance. It may oscillate in a particular direction to produce electron and in some other direction to produce photon or a quark. It is postulated that these strings can vibrate in 10 or 11 dimensions, the dimensions that we cannot see at present.


The theory smoothens out the inconsistencies between quantum theory for tiny mysterious universe of fundamental particles and theory of relativity for big things. It has the potential to explain the theory of multiverses or parallel universes, the Big Bang Theory and supernatural experiences too!! There has not been an experimental proof of the string theory, the whole picture is still missing but with time and technical advances, we might as well be able to justify many unexplained phenomenon and build time machines based on string theory!!