The mechanical watch market is an industry with an unusually high preference for tradition and history. This would make sense, since the advent of electronic quartz watches has filled the role of practical and affordable timepieces; anyone who is looking to buy a mechanical watch is doing so not solely for its practical value, but for its prestige, unique appearance, or craftsmanship.

Often, mechanical watches are wanted for their complexity. Watches with unique mechanisms are interesting, and knowing that all these mechanisms are sitting in a small cylinder on your wrist is awe-inspiring. Unlike most products, where simplicity is valued, the more complicated a watch is, the higher its value.

Watches are made complex by giving them extra functions called complications. Complications can be practical and mundane, like a seconds hand or a date counter. However, because of the allure of complicated watches, the the demand for increasingly complex watches is always there.

However, despite this complexity, the basic mechanism by which a mechanical watch functions is the same across almost all watches. The watch’s mechanical components, collectively referred to as the “movement,” consist of the mainspring, the balance wheel, the escape wheel, pallet lever, and the gear train connecting these parts to the hands on the face of the watch.

The mainspring stores the energy for the watch in a springy metal coil. This energy is released by through the gears of the watch. But how does the mainspring not release all of its energy at once in one great spin of the hands of the watch? The secret behind this is the escapement.

The escape wheel is the toothed wheel in the bottom left (yellow). The escape wheel is powered by the mainspring, but it is stopped from freely rotating by the pallet lever (slime green). The pallet lever acts like a gate that restricts the rate at which the movement turns, and thus the rate at which time passes in the watch.

The pallet lever pushes the balance wheel, which (relatively) slowly swings back and forth, which pushes the pallet lever back to its original position. In the process of returning to this original position, the pallet lever allows one tooth of the escape wheel to pass. In other words, the escapement (this entire mechanism) allows one tooth to “escape” every sixth of a second (which is the oscillating frequency of the balance wheel).

This is how our watches keep time. Without the escapement, mechanical watches would be nothing more than a springy gear train on our wrists. However, with the escapement, the springy gear train on our wrist releases energy at a constant rate, keeping constant time.

While this ingenious mechanism appears complex, it is old technology dating from the 1750s. Since that time, it has barely changed at all. This mechanism has endured the test of time and is still standard in almost all mechanical watches today.

The space launch industry is getting a lot of press in recent years due to rapid advances in rocketry technologies and achievements. Most notably, SpaceX’s propulsive landings of their boosters have been very popular. These events get press not because they’re especially relevant to the daily lives of the everyday citizen, but because they are awe-inspiring. The amount of complexity and ingenuity that is behind these incredible events is beyond the scope of imagination.

However, not all rockets are that complex. There are a wide range of rockets of different sizes and shapes with different applications. Many other launch vehicles (rockets) do not feature propulsive landing or even reusability, vastly reducing the amount of complexity in the system. Going further down the scale, we find rockets that do not fully achieve orbit, but simply carry scientific equipment to the upper atmosphere or space for a short period of time. Once you reach consumer-level hobbyist rockets, certain aspects such as payloads, wireless communications, and navigation are not even necessarily included. In fact, you can buy a hobby rocket kit for as little as twenty dollars* that consists of less than 15 parts!

Fundamentally, all a rocket needs to be called a rocket is a pointy body and a rocket engine/motor that launches it up. At the most basic level, this motor can simply be a homemade concoction of sugar and Potassium Nitrate (bought from a home improvement store or a pharmacy) that is stuffed into a capped PVC pipe. More commercially available rocket motors may consist of gunpowder wrapped in a paper casing, such as this one made by Estes Rockets:

When these engines burn out, they usually also contain what is called an ejection charge, which creates a small, controlled explosion at the top end of the motor which would eject the nosecone of the rocket and deploy the parachute.

Rocket hobbyists often like to know how fast and high their rocket went, so a more advanced hobby rocket would contain avionics. Avionics simply refers to all electronic components of a rocket. In this case, the avionics would consist of a battery connected to an altimeter which measures the rocket’s altitude over time.

High-powered hobbyist rockets that reach higher altitudes are under stricter regulation by the FAA because they can interfere with aircraft in the sky. These larger, more complex rockets may contain multiple motors arranged in multiple stages. They may also contain more advanced avionics, such as GPS-tracking technology and computer-activated parachute deployment at a specific altitude.

Even higher-flying rockets such as sounding rockets are the aforementioned class of rockets that often carry scientific equipment into space. These rockets now contain a payload (the scientific equipment) that the rocket needs to be designed around. One of these design requirements is likely a target altitude that the equipment must reach to obtain useful scientific data. These powerful rockets often need more advanced rocket motors than the standard solid rocket motors of the hobbyist world. More powerful rocket engines often use liquid fuels such as hydrazine, kerosene, or liquid methane. While using liquid rocket fuels massively increases complexity of the rocket motor, it allows for more precise control of thrust, as well as the ability to completely stop and restart the motor when desired.

Last, but not least, we have reached where we began: orbital launch vehicles. These rockets differ from all the aforementioned smaller rockets not only in that their power, but also their precision. Not only does an orbital launch vehicle need to reach the speeds necessary to achieve orbit, it also needs to place the satellite payload in the specific orbit that the client has ordered. All of this needs to be achieved under the intense stresses experienced by accelerating a three million pound rocket to 32 times the speed of sound**.

Depending on how you look at it, rocketry can be dead simple or the most complex thing in the world. However, they all share the same underlying characteristics and structure.

 

 

*ten dollar rocket with ten dollar motor
**specifications of the SpaceX Falcon Heavy

You may have had to work with a compressed folder before. Likely, you’ll remember its icon (a folder with a zipper). Maybe you remember that the file you downloaded ended with the .zip file extension. Every time you download a compressed file folder, you have to go through the annoying step of clicking “extract” to get your files. What’s the point? Can’t the files you want just be downloaded as they are?

The answer to that question is yes, but not really. This is because while websites have the ability to host and send uncompressed “original” files/folders, these are much larger in size than the compressed version. In order to increase efficiency, downloads and uploads of large/multiple files are done using file compression.

But how does this work? How is it possible that a file can just become smaller?

File compression works by reducing redundancy. This is best explained with an analogy:

Let’s suppose you wanted to write a comprehensive list of instructions on how to assemble an IKEA dining table and chair set. When writing the instructions to install the legs onto the chairs, you probably would not write the instructions one time for each leg of the chair. Rather, you’d write it once, and then indicate to repeat it three more times, once for each leg. Similarly, when writing instructions for assembly of the chairs, you would only write one, and then indicate to repeat the process once again for each remaining chair.

via GIPHY

This is the essence of a compressed file. Repeated consecutive data is condensed into a single copy of that data with an indication of how many times that file is repeated. Other patterns in data can also be picked up by compression software and condensed into more compact data.

The above form of compression is called “lossless” compression because when decompressed, the output file is exactly the same as the original. However, for certain applications, not all data needs to be perfectly retained. In the world of audio and video downloads, “lossy” compression leads to even smaller files that, when presented to most consumers, are practically indiscernible from the original media. In this form of compression, not only is redundant data eliminated, but data that encodes details that the consumer will likely not notice is also eliminated.

Exactly what data encodes “details that consumer will likely not notice” is determined by the type of file compression used. For example, in audio files like mp3 files, one way in which compression is achieved is by ignoring very quiet sounds that play at the same time as louder sounds. Another way compression is achieved is by eliminating very high and very low frequency sounds that humans usually do not perceive.

With a lossy audio compression method like mp3, a song can be compressed to a file 11 times smaller than the original. In contrast, a lossless audio compression method like FLAC (which, again, only eliminates redundant data) can only compress a song to about half its original size.

From the outside, file compression seems like magic. At the detailed level, file compression is highly technical and difficult to understand. However, on the surface, file compression is comprehensible: it just gets rid of things you don’t really need.

PC cooling isn’t something you’d expect to be interesting at first glance. You probably are thinking of your laptop’s annoying fan that spins up occasionally, or maybe you think about your desktop at home and it’s dusty fans. However, in the world of hobbyists, anything can be crazy if you throw enough money at it.

People throw money at PC cooling usually for one of three reasons:

1. They are a PC speed addict
2. They are looking to break PC speed world records
3. They have a lot of money to throw and nowhere else to throw it

Often, these hobbyists install a liquid cooling system (not unlike that in a car) with a pump, a radiator, and pipes leading to and from the hot components. These tend to look quite nice and perform well. However, things get more interesting the deeper down the rabbit hole you go.

If someone wanted a nice conversation starter as a PC, they could end up with something like this:

This is a PC submerged in a special liquid formulated by 3M that is electrically insulating and thermally conductive. It also has a very low boiling point (34°C) such that it simply boils off at the surface of hot components and then condenses at the surface of the fish tank PC and releases the heat to the air.

This is not the most practical way to cool a PC. (This is definitely not the most practical way to start a conversation.) Replacing a component would be messy work, and the PC would probably have to be drained and refilled every time it is transported. Oh, and 3M’s special liquid is $285 per gallon.

However, you cannot argue that this is not pretty interesting. Maybe it could get more interesting, though; we need to go deeper.

This is a computer motherboard. Yes, that is frost. For those few looking to break world records, this is how they go about it. First, they tell the computer to draw tons of power and ramp up its internal speed. Then, they pour liquid Nitrogen or liquid Helium into the “pots” on the (not for long) hot components of the PC.

This may seem like overkill. After all, liquid Nitrogen exists at -196°C and liquid helium exists at -270°C (which is 3 degrees above absolute zero!!!). However, people looking to break world records are looking for every last drop of overkill they can get.

At this point, it may seem a bit strange that these things even exist. What’s the point? Can’t I just keep on using my good old air-cooled HP laptop? Absolutely. Air-cooling still works and is still cheap.

Honestly, I can’t come up with a good reason for these methods to exist. They’re a waste of money for most people and don’t give much in return. However, hobbyists will be hobbyists, and I’m glad. I’m glad because they’re out there creating the next crazy technology and I get to sit here, on my regular air-cooled PC, and watch the incredible technology develop right in front of me.

In a previous post, I explained how a standard consumer 3D printer works. However, why would anyone use a 3D printer? In this post, I will go over the benefits and downsides of 3D printing parts instead of manufacturing them with more conventional methods.

Before speaking on the use cases in which 3D printing is viable, I first want to cover 3D printing’s major downside: it’s takes a really long time to print large quantities of objects. On the other hand, traditional methods such as vacuum-forming and injection-molding can produce massive quantities quickly and cheaply once properly set up.

However, it is this setup that is what is holding traditional manufacturing methods back. These methods require that you take the time to make specialized molds and other specific pieces. This time is tough to justify when you only need to manufacture a small batch of maybe 50, or even 5 parts. This leads me to the major upside of 3D printing: easy, immediate results. Once a design is decided on, a 3D printer can print out a copy of the design within a day, or even hours. Especially for people prototyping and constantly changing a design, having to create a new mold for a traditional plastic forming method would be dreadful. With 3D printers, each new design can be (almost) immediately obtained and tested.

Another downside to 3D printing is the limitation in choice of materials. Most 3D printers can only print in a few types of plastic (and sometimes pancake mix). A few industrial 3D printers can print with metals and ceramics. However, if you want a part made of wood or glass, 3D printing can’t make it yet.

On the other hand, 3D printing can create things with these few materials that other manufacturing methods simply cannot do. Take, for example, this faucet:

The water runs up through the inside of the spindly, hollow helices and converges at the top, running out the head of the faucet. Traditional manufacturing methods cannot produce complex geometries such as the hollow, spiraling, intersecting metal pipes seen here. This is something that is only possible through 3D printing.

3D printing is also known as additive manufacturing. This is in contrast to many subtractive manufacturing methods which carve out material from a large chunk to form the object, such as turning and milling. These subtractive manufacturing methods by nature waste material as they carve, making working with expensive materials difficult. However, with 3D printing, expensive materials can be preserved by only using as much material is needed to create the part. This is why additive manufacturing (3D printing) is becoming more popular in the aerospace industry; titanium airplane parts are expensive, and 3D printing enables companies to create large parts out of titanium without the traditional large amount of waste.

Because of the above reasons, 3D printing is becoming more and more popular in manufacturing and engineering. While it is slow and limited in materials, it can create things that other things simply can’t, and it can produce them immediately.

The title says it all. How can you transfer energy from a wall outlet to a battery without touching it? After years of understanding electric energy as transferred through wires, wireless charging seems like magic.

This magic is important to understand because wireless charging is only becoming more ubiquitous. Wireless charging capability comes standard on most flagship smartphones produced today, and the technology is slowly being applied to other chargeable devices such as electric vehicles, wearable technology, and medical implants. Wireless charging is going to be a part of our society, whether you’re ready for it or not.

To be ready, here’s what you need to know. Wireless charging works by creating a magnetic field generated by electricity passing through a wire coil within the charger. This magnetic field is the “invisible magic” at work that spans the gap between the charger and the device, transferring energy without wires.

Due to a special physical phenomenon known as Faraday’s Law, this magnetic field produces a voltage in a matching wire coil within the device that is being charged. This voltage is the electric equivalent of potential energy.

At this point, we have successfully transferred electric energy across a gap with no wires! Hooray! The last step is using this voltage to charge the battery, just as if it was plugged in to a standard charger. At this point, the process of charging is complete.

Armed with this knowledge, you can debunk many misconceptions about wireless charging. For example, some avoid wireless charging lest its “radiation” leave harmful effects on their body. In this case, we know that there is no nuclear radiation here, simply electromagnetic energy at a very small scale.

Another misconception is that wireless charging is significantly slower than wired charging. While this used to be true, manufacturers are now selling wireless fast-chargers that charge much faster than before, even faster than standard wired chargers. While a wired fast-charger still edges out the win in charging speed, wireless charging is barely behind. (This is especially true of iPhones, since there is no wired fast-charger for iPhones.)

If you happened to know that metals redirect/affect magnetic fields (if not, then you do now), then you would notice that the annoyingly fragile glass phones of today are not completely purposeless; many phone manufacturers (including Apple) have switched from aluminum-backed phones to glass-backed, because wireless charging is incompatible with metal phones. This is also why cases designed for phones with wireless charging capabilities no longer are ever made of metal; wireless charging just doesn’t go through metal surfaces.

Overall, wireless charging isn’t too complicated; physically, the technology only consists of a coil of wire. However, the technology is the capability of changing the entire paradigm of how electronic devices, appliances, and vehicles are designed and used. Armed with this simple tool, we could see a revolution in consumer electronics in the coming years that reaches far beyond just smartphones.

Keyboards are part of our everyday lives. They are one of the main ways that we interface with our computers, which we use every day. They are the means by which we submit our ideas to the global forum of the internet.

Shoes are part of our everyday lives. They are one of the main ways that we interface with the world, because we use shoes to help us travel to achieve what we need to do.

It is generally understood that shoes are worth spending on, because we use them so often. Skimping on shoes results in discomfort, health issues, reduced efficiency in travel, and short-lived shoes that need to be replaced often. When people buy shoes, they often buy the best they can reasonably afford.

Why is it not the same with keyboards?

For a few people out there, it is. And when it comes to buying the best, there is no question as to which that is; mechanical keyboards are the best.

Why are mechanical keyboards so good? To answer this question, we must first consider the difference between mechanical keyboards and your run-of-the-mill office keyboard.

Most regular keyboards are rubber dome keyboards. That means that when you press the key, it depresses a small rubber dome that, when depressed, completes a circuit and sends a signal to the computer indicating that a key was pressed.

The problem with this mechanism is that rubber isn’t the most consistent, durable, or responsive material for keyboard keys. They are most often described as feeling “squishy.” The force required to depress a rubber dome switch varies greatly between keys or even between different presses of a single key. The force required to depress a switch varies even more as stickiness and jamming develop. Overall, rubber dome keyboards are not pleasant; some even describe them as odious. To go back to our shoe analogy, rubber dome switches are the equivalent of generic Walmart flip flops.

Mechanical keyboards, on the other hand, rely on a spring as their switch mechanism.

These are extremely consistent in force required for actuation and feel, and boy do they feel good. (I know, I just said a keyboard feels good. Don’t make fun of me.) They are usually rated to last for 50,000,000 presses, and could probably survive being typed on by a hippo. I’ve never heard of anyone needing to replace a mechanical keyboard because it wore out; people always upgrade because they realize they want an even better mechanical keyboard.

That’s the one small (or large, depending on the person) problem with mechanical keyboards: once you use one, there’s no going back, despite the dramatically increased price. Every rubber dome keyboard I end up having to use in campus computer labs feels to me like typing on under-cooked noodles. But that’s not too dissimilar to switching from flip flops to tennis shoes for daily drivers.

However, just like tennis shoes, mechanical keyboards range from the budget staples to premium standard-setters to extravagant collector’s editions that come out in batches of 100 with assembly required, imported directly from South Korea. These premium keyboards are the ones for the aforementioned people who have a large problem with collecting keyboards. However, if you’re just a regular consumer looking for a reasonable product, most mechanical keyboards can be found for between $40 and $100. This price is worth it, in my opinion and the many others who own one. However, be warned: once you try it, you can’t go back.

Albert Einstein once said, “if you can’t explain it simply, you don’t understand it well enough.” In these blog posts, I will do my best to simply explain topics that (I think) I understand. These posts will serve to inform you, the reader as well as improve my own knowledge on the topic at hand.

Most of the topics will probably relate to my personal (non-academic) interests, including computer building, 3D printing, cello playing, and many others. If any of these topics are unfamiliar to you, I hope that through this blog you may find that some of these things are less intimidating than you thought.