Category: Engineering

A Layman’s Guide to Photonic Crystals

The first time I heard the word “Photonic Crystal” in a seminar, I was stumped. So I decided to read about it, understand and then write about it to make it explain better to me, and you of course. Even though it is a whole graduate level class to explain, it does not hurt to quickly look at how Photonic crystals work. I have not taken the relevant graduate class. However, after reading this amazing answer on Quora, and from a range of other literature out there, I was able to make some good sense out of it. My idea was that at least by doing a little reading you get to throw around a fancy word like “photonic crystal”. Moreover, if someone decides to test you on what it means, you even explain it to them. These kind of examinations, where it is incumbent upon you to perform well, happen all the time, everywhere. That’s why it is important to learn. And well, then there’s that whole argument of expanding your mind to exercise your creative muscle by reading and listening carefully to things and people that are out of what you do.

Featured image credit: Flickr, Steven & Courtney Johnson & Horwitz (Picture)

Continue reading A Layman’s Guide to Photonic Crystals

Some Inventions That Caught my Eye

By Anupum Pant

1. The tethered drone which follows you like a kite and keeps filming you. It uses the tension in the tether to determine where you are and where you want it to move to.

2. A 3D pen which can be used to write things in 3D. But those are many, you’d say. The twist with this one is that it comes with a soldering attachment, a burning attachment and a foam cutting attachment!

3. A smart halo which attaches to your bike permanently and connects to your smartphone. Finds you the best bike path for you. It points you at every turn and warns you for other things. Also tracks all of your workout. Also alerts you if someone tries to steal your bike. The phone remains in the pocket. Oh, and it also has a smart light!

4. A special 3D printer which can also engrave and do PCB milling. It can also scan things in 3D and recreate them for you.

5. The last one is a hi-tech backpack that has places for a technophile, from USB ports to speakers to charger or a place 3G to wifi device.

How do Shock Absorbers of a Car Work?

By Anupum Pant

A lot happens under your car when you are driving – the area which you never get to see doing its job. Chris put a video camera under the car to show a detailed review of what happens under your car. To add to that he also compares how old worn out and new suspensions are different and which clearly tells you why you should replace your shock absorbers when they go bad.

The Marvels of Samsung’s S Pen

By Anupum Pant

It’s amazing how far technology has come. The S pen you get with a Samsung note device has no battery in it, and yet it is powered because it can somehow communicate with the device. The communication is obvious because the pen has a button and if you press it, the phone knows.

So how does this work? What kind of sorcery is this.

The pen actually pulls energy wirelessly from the device itself with the help of electromagnetic waves. It is something like a device bremen-based designer dennis siegel built in the year 2012. He showed us how he could charge his batteries by harvesting the omnipresent electromagnetic energy. Although it used to take about 24 hours to charge a normal AA battery, now a similar tech is encapsulated in a tiny device, actually even thinner than a real pen!

Electromagnetic Harvester from Dennis Siegel on Vimeo.

Precision Metal Cutting by EDM

By Anupum Pant

Metal machining is a common term. Almost everyone knows about it. It’s simple and a cost efficient way to cut simple shapes out of metal. However, very close tolerances are hard to achieve unless the  machine is absolutely state of the art.

Wire EDM or wire electrical discharge machining is something that can cut metal extremely precisely into very complex shapes and achieve tolerances that are in the order of a few microns – about 100 times thinner than your. Its called a wire EDM because it uses a wire that is extremely thin, as thick as a human hair, to cut into a metal. The metal powder removed from the cutting process is so small , you could consider it smoke. This is how it works – LINK

In the right hands, this is what it can do…

Plastic to Oil

By Anupum Pant

Plastic is a huge problem. It’s filling up the landfills, causing problems to the animals and what not. But did you know, there’s a very simple method you could use to convert plastic to a general purpose oil – something you could burn for heat. The same oil can even further be distilled to separate gasoline, kerosene and diesel. All you need to do is to construct an apparatus like the person uses in the video below.

An apparatus that would heat the plastics in an oxygen free atmosphere to at least 400 degrees centigrade. This would cause the long polymer chains of plastics to breakdown due to a process called pyrolysis. The end product would be vapors of oil which can be cooled down and collected for general burning. A kilogram of plastic used would produce almost a liter of oil. If you’d rather burn the plastic, it would produce about 3 times as much carbon dioxide in weight. Considering it’d get burnt anyway if you make the oil, at least you’d now have a far more richer and cleaner source of heat.

Mushroom Batteries get Better as they Age

By Anupum Pant

Researchers from UC Riverside are definitely onto something here when they say they have found that your humble Portobello mushrooms may have the answer to batteries that might actually get better with age. Yes, you heard it right. Better as you keep using them, and have electrodes made out of Mushrooms!

Using nanostructures from a mushroom and treating it with KOH and high temperature, the researchers made anodes from this natural highly porus structure which can hold a lot more number of lithium ions than your traditional synthetic graphite, thereby increasing capacity.

Moreover, since mushrooms are rich in potassium salts, as the batteries get used, more number of pores open up, thereby increasing the capacity more. Imagine having phones whose batteries improve charge times as they age!

The batteries made right now are no where close to what commercial batteries are, however this might be a great stepping stone for amazing batteries of the future.

[Paper]

Lifting Boats Efficiently

By Anupum Pant

The fallkirk wheel in Scotland is probably one of the engineering’s most ingenious designs. It is the world’s only rotating boat lift. It is a massive piece of equipment which harnesses the basic laws of physics to drastically reduce the energy input used to lift boats from one canal to another, 80 feet up. Tom Scott explains…

Mechanics of a Retractable Ball point pen

By Anupum Pant

The three main parts of a retractable ball point pen work in unison to produce 4 clicks for every cycle of retraction. Here’s a great explanation of how all of it works. The engineer guy breaks down the process into eight steps and reveals the interior workings of a click pen in the following video.

Actually Making a Sandwich

By Anupum Pant

How hard is making a sandwich. Not so much, right? Actually, if you try to make it from scratch it takes way too much effort than you can imagine. This man tried making every ingredient from scratch. Thankfully, he didn’t try making the equipment used to make the ingredients. Even then, it took him a complete 6 months and $1500 to make a single sandwich. And at a fast food place, you can get one for less than $5. That’s how far we’ve come.

If you think about it, this is what it takes to make a sandwich from scratch. Plant vegetables, get sea water to make salt, make salt, harvest vegetables, make pickle, wait for it to pickle, get wheat, make flour, bake breads, milk a cow, make cheese, collect honey, make butter, kill chicken, assemble and enjoy. And each of those things isn’t as easy as it sounds. Watch him do it…

A Drone Chariot

By Anupum Pant

Using 54 counter-rotation propellers arranged in the shape of a hexagonal this man has built for himself a drone-chariot or a super-drone-vehicle of some sort. Apparently the super drone vehicle is powerful enough to lift 164 kg placed in the center seat. That’s quite enough to lift a person driving it. It moves around pretty well too. Older tests were recorded on video and here’s the latest success.

If you don’t call it a success, well it sure can be used as a massive leaf blower.

Water Wheel Pump

By Anupum Pant

This is amazing engineering. It probably is a very common thing for some people. But this caught my attention because I’m seeing it for the first time. I found it on scidump.

It is a water wheel that has fins overhanging by its side. When the water from the river flows against the fins, the fins are moved forward and the wheel spins. The wheel itself is actually a spiral pipe which picks up water from the outermost part of the spiral, from the same river while it is rotating. The spiral then moves inwards and sends water into a pipe at the center axis of rotation. The water is then carried to a tank located several feet from the wheel. It uses no electricity, is powered by the river and is used to transport the same water which powers it. Amazing!