Posts Tagged ‘ homework ’

Why you should not jump the turnstile.

One the first things they tell you as a foreign graduate student in New York is that you shouldn’t jump the subway turnstiles and I’ll tell you why.

Sadly, the New York subway is my current form of transportation to the city and therefore have had lots of experience with it despite only having lived in the city a little over two months.

I first rode the New York city subway in 1994 when I first came here. Back then it was powered by tokens. They were easy, just pop them in and enter. No need to get a confiramation that you paid your fare.

When I came back in 2002, metrocards have been introduced and it took my father a bit to figure out how it worked. There wasn’t any indicator on what direction we were supposed to swipe it in until a stranger got the card the swiped it for us. Whew!

In my station, there are two ways to get to the Manhattan bound trains. One is through a regular turnstile and the other is through the more secure rotating type door that you can’t hop over.

I’ve noticed that regular commuters, when faced with urgency (like the train is on the platform) will make a dash for the first vacant entrance they see.

For months I used the rotating door turnstile and not the regular turnstile though it seemed faster.

People would swipe their metrocard on the sensors which are a pain for me sometimes towards the end of the month when for some reason the sensor would not recognize my card which is annoying. There are those who will swipe their card twice and they’ll get in. But usally if it hits 3 times, you can’t use the card at that entrance anymore which is a pain.


With the exception of families with strollers, I’d say that most people use both entrances equally. People would go to the first available one or the easiest to access. Much like electricity, they head to the path of least resistance. Those with children would gravitate to the much easier traditional turnstyles compared to the swivel type.

Of course those without a ticket, will jump over the turnstyles unbeknownst to them of the plain clothes policeman who is known to linger in the station from time to time.


More often than not, most users would not look at the indicator to pass unless they couldn’t. Those with stored value cards would occasionally look at the amount remaining on the card while others will just run by.

It’s actually interesting to watch people handle the subway metrocard shuffle. I’m more used to the RFID card type of transportation and I asked a friend to send me pictures from Singapore about their underground system.

Using whatt they call an EZlink card, they use it for a variety of items such as paying for public transportation (including taxis), toll fare, and even buying stuff from 7-11.

The method of using the card is effortless.

Just tapping the card om the sensor and off you go.

II wonder when New York will catch on to this?

Serial conenction

Hooked up the arduino to the mac via USB and using Processing to show a visual reference to the connection which I’m manipulating via the potentiometer.

Servo and Tone

I think I’ve just made my own Theremin Machine. Or at least something to annoy the neighbors.


This week’s CommLab2D homework is about typography.

So how would my name look like in typography?


I’ve selected 3 serif and sans serif fonts to fit the bill. From my name it’s important for me for the font to have prominent A’s, M’s and D’s.


It’s important for me to present the “A” of my mother’s maiden name due to the fact that there are technically 3 Melissa dela Merced’s in the family. The only letter that separates us is the middle initial and I’ve selected it here with Serif font, “Bergamo”.

My name has Spanish origins and traditionally the word “dela” is not counted alphabetically and is set in the lowercase. Using the font “Merriweather”, this allows a balance in the letters that are important to me without having to sacrifice any.


“Quattrocento” is an interesting font for me that I would like set in steel infront of my future office. This it almost looks like a sans serif font but the A’s and the M’s give it away.


“Days” is a sans serif font that I would like to put on the side of a race car. There is a certain amount of flair in the A while maintaining the orderliness of the rest of my name which I would describe me as a somewhat traditional person.


I’ve set my name in this order since I share the same initials as my mother. “Salaryman” represents my family. The way that it lines up the MDM together.


“Hattenschweiler” is what I call the Star Trek font or how your name is usually written in rallycars. I place it here as my fondness for both.


These are just a few of my experiments in typography. Two of which is based on what I was feeling over the weekend while the other came from a random word I saw on the internet.

Let’s play with electricity


This week doesn’t require any mad programming skills and just basic electrical know how.


With the help of helping hands, this allows me to both hold the points together to get a reading on the multimeter and take a picture at the same time. Of course this one beeps.

So does this one. Notice that I wired the board in such a way that both sides have power and ground.


Which of the images above has a complete circuit?

But fun question, does electricity pass through our bodies? Yes, but we still provide enough resistance that the 5V from the Arduino will not shock us nor complete the circuit.


And just like that with a resistor and all, we have another lit LED.


Interesting that the LED uses approximately 1.72 V out of 5V.


The amount of electricity passing through the resistor is approximately 3.31 V. Add that up it’s almost 5V. At least we know where all the power is going.



Let’s add a switch and see if it affects the power flow.


Well apparently all it does is just cut off the power completely.


Notice that the gree light is not as bright as the red one. Different color LEDs have different power requirements.



Notice the difference between the power usage of the green and the red LED and the amount that passes through the resistor.


Now when we add another LED, they don’t light up as brightly as before.


The resistor is now only getting 0.14 V.


But if we re-arrange the LED’s that they’re all being powered by a single line instead of a series of leads. It’s a whole lot brighter.


The resistor is using up 3.38V. while the LED’s are at 1.65 V.


Under pressure

Named after that song from Queen, now I have to program the arduino to recognize an analog input. Meaning, it’s not just as simply flipping a switch. This requires and entirely different mindset.


Using a knobthingy commonly known as a “potentiometer”, it allows the light to switch on once you turn it past a certain point. Notice that the potentiometer does not use a resistor and is an exception to the rule.

Now I wanted to control the intensity of the LED using a light sensor. So I ended up with this. It still needs a bit of tweaking on the range the sensor recognizes but it more or less captures the desired result.

I’m still working on two LEDs and two pressure sensors.


What are the sensors in my neighborhood?

This weekend while taking the subway I noticed a number of physical sensors that I didn’t notice before.


This particular button is not common in New York well at least I haven’t seen much of it in Manhattan. But pressing this button will tell the traffic signal light that there is a pedestrian who wants to cross and the light will change shortly afterward. But then again, it could be a placebo effect, giving the user the illusion that the light will change soon but in reality, it’ll change when the program tells it to change.


Here’s a light that doesn’t have a sensor but in my opinion needs one. I see three different sensors that could work here. One is light sensor, which would tell the streetlight to turn off once it detects a particular amount of light (supposedly sunlight) to detrmine it’s on and off. Another is solar panels so it’s not too bad that the light is on all the time since the light is powered by solar energy. Then the third sensor would be the exisiting sensor which is based on time. Much like water sprinkers, these are set on a timer where the on and off is determined by a timer on the switch.


The Metrocard machine is a plethora of sensors. There are the input buttons on the touchscreen. There’s the numeric keypad for credit card and debit card holders to enter their information. The coin and bill sensors that determine US legal tender is being inserted into the machine. The braile pads that help the blind in getting their passes. And then of course the Metrocard slot where the machine either accepts or dispenses the card and reads how much is left on the card.


Of course what’s a Metrocard without the sensor that you use it on. Other cities such as Singapore, Tokyo, Hong Kong and London use RFID cards instead of the magnetic strip that the NYC transit system uses. I first used the Metrocard in 2002. I was used to the tokens all this time that it took a while to figure out which direction the magnetic swipe had to be for it to work.


I’m not sure if it can be seen here but I suspect the subway is outiftted with all sorts of sensors. Most of it detecting the position of the trains. This particular sensor at the station, I guess that sensor tells all the other trains along the line that there is a train present at this station and informs the other stations down the line with the announcement ” There is a Manhattan bound train one station station away.”

I saw this at church today. This emergency light has an electrical sensor. In the event of a power outage, these lights turn on.


These exterior lights can be switched to detect motion in the event someone walks in front of the range of the sensor. This is great at night so you don’t have the light on all the time.


At the MOMA there is this device. Though not part of the installation but still has the “do not touch” warning next to it, I could guess that thsese are motion sensors that detects the presence of someone in front of the display. This is only present on displays that use a monitor and will then play the video once there’s a person in front of the display.



The displays are each identified with QR codes which directly links the viewer to a website with more information about the artwork. Of course in order to read this, your smartphone should have a QR reader.

Barcodes on everything is no different. These help stores and companies track inventory as well as make purchases accurate and efficient at the checkout counter.

If I see anything more before Wednesday, I’ll update this post.

Blink that light

We don’t give it much thought when we turn on a light bulb. For us it’s just a flick of the switch and that’s it! So it shouldn’t be too much trouble. Or could it?

I picked up the ITP PCOMP kit at the NYU Computer Store for around $93 including taxes. Inside it’s a box of chips, LEDs, wires, boards, cables and so on to supposedly help me make magic.




First thing to setup is the breadboard (that white thing above) and the arduino board to the plastic mounting. You’ll need screws for the arduino but the breadboard has doublesided tape.


No switches or anything just power up the LED using the microcontroller via USB power. Even if the kit comes with a 9V adapter, I think it’s safer using USB. You can’t accidentally burn out the circuits as the computer will automatically turn off the port if it detects a short.


What’s wrong with this picture?

The board via the PWR lead as marked by the red wire and inserted a resistor and a green LED. Obviously this wouldn’t work since the breadboard isn’t powered and there’s no way that the digital lead is going to provide power to the board.


Let’s get some power.

The Arduino app is another matter entirely. Even though the user interface is similar to Processing, some of the syntax and commands are similar to a point.

I used the code in class and replaced the port numbers since I was using different ones than the ones in class. I learned the important part was to keep it simple and understand the logic of the board and it’s there!


The trick to making the LED blink is all in code using the “delay(x)” .


The switch was more challenging than the earlier two.


Now this needed a little more patience since I was adding another item which is the switch that needed a separate command for the microcontroller to command.

I ended up with this board.


And there you have it! A working switch. I’ll toy around with kit some more over the weekend but it’s great building something with your hands or in this case my hands and the computer.