Author: Zhiyu Guo

In-class Recitation

For more detailed documentation and code files, see the collaborative notion page.

Teamed with Mia, Freya, and Annika, we made a wireless circuit, taking advantages of the X-Bees. Besides the complex instruction and the fancy materials, the overall circuit was easier than I thought. We built a wireless circuit with two ends, one sending signals generated from one photoresistor, the other receiving the value and showing the transformed data in Processing.

Annika and I mainly focused on the first X-Bee (and lilypad A), the one sending values from the brightness sensor. Before building the circuit, our first step was to match the two X-Bees together. Using the application XCTU, we matched the X-Bees with the same pin code and assigned the sending and receiving duties to them.

The next step was to connect the X-Bee to a normal Arduino circuit. We first built an simple Ardunio circuit with the photoresistor, such that the circuit takes an input from the brightness sensor, and the value varies when light is shed on the sensor. Then, we tried to add the X-Bee to the lilypad, so that the lilypad would output the brightness sensor’s value to the X-Bee.

We met two major problems in this step, the first one is about connecting the circuit with the battery. The given circuit was to connect both the X-Bee and the lilypad to the 5V battery. However, we only have our laptops to battery them. After trying to use two laptops to charge each of them, we then figured out to just simply connect the lilypad to laptop, then use the 5V port on the lilypad to charge X-Bee. Our second problem was to test if the circuit was fully functioning. We tested before that the lilypad and the photoresistor were both working, but we were not sure if X-Bee is receiving the value from our circuit and successfully sending that value to the paired X-Bee. We tried to follow the instruction of changing the input and output pins and monitor the X-Bee values, but we failed to find that exact window monitor in the XCTU application.

  

Although we did not succeeded in testing our part of the circuit, we saw the whole circuit working smoothly once Mia and Freya finished their part of the second X-Bee. The photoresistor sensor value was shown on their Arduino window monitor in real time. One minor problem we encountered at this stage was that in circuit X-Bee B, the received value was intended to control the brightness of one LED. However, though we succeeded in receiving the value, our LED never blinks or dims. Even after we finished the whole exercise (where the Processing was controlled by the photoresistor), the LED problem was unsolved. With help from the professor, we finally figured out that we accidentally gave to inputs and outputs to the LED, saying that we have one input controlled by the sensor, and one other input of constant 5V. Therefore, the LED was always reacting to the 5V input and had a constant brightness.

Our next step was to create a simple Processing animation so that the brightness sensor value could control the radius of a circle on the screen. The processing part was also not difficult, and we finished it pretty smoothly. 

 

We then spent the rest time of the class exploring the neopixel stripe, one stripe that has around 50 to 60 LED on it. However, we did not really figured out the neopixel stripe FastLED library in Ardunio to control all LEDs at the same time. Therefore, we did not add the colorful stripe to our circuit at last.

 

After-class Questions

How do you imagine you could use what you learned today for a wearable?

What I learned today is basically wireless circuits, where different parts of the circuit does not need to be physically connected through wires. So inputs (sensors) and outputs (LEDs) can be at different locations, and even multiple inputs or outputs can also be at different places. Such idea efficiently widen the potential for any circuits on wearable. Where the circuit is no longer fixed at one position, this creates millions of new potentials.

Some of the simple implication I could think of are that inputs and outputs can be at different locations of ones body, maybe the movement of head could control lights around your ankles. Another is to have wearables react to the environment, for example the input is controlled by some equipments away from the user, and the wearable could receive this long-distance signal and have reactions. One more exciting usage is that two wearables could interact with each other, maybe two people wearing these pair of wearables, and the movement of one people could have interactions on the wearable of the other.

In-class Recitation: Circular Potentiometer

Annika and I made this circular potentiometer using velostat and conductive fabric. Building the sensor was not difficult, after cutting the two circular fabric, Annika sewed them with a piece of normal fabric to secure them.

  

Though I have been away from Arduino codes for roughly two years, luckily, the codes for this circuit is very simple. It takes an analog input from the potentiometer sensor, maps the value into a certain range, and outputs it to the LED. Such simple code is attached at the bottom of this section. The circuit is also straightforward, the circular sensor is connected just like the normal potentiometer, one 5V, one analog input to Lilypad, and one ground. LED is connected with the input from Lilypad, one 220R resistor and then to the ground.

  

The most challenging part was to connect the Lilypad with the laptop and upload the codes. Even after choosing the correct port and verifying the codes, we failed to upload it many times. While the codes was successfully uploaded to the Lilypad at last, we still don’t know what went wrong and why it worked.

The circular sensor works in an intuitive way that as you moves your finger around the circular fabric, the input signal changes. To be specific, when your finger is close to the positive end, the end connected to the 5V, the sensor has higher outputs; the numeric number drops when your finger moves away. In our circuit, such changes is reflected in the brightness of the LED. The LED dims when your finger moves towards the ground end. However, our circuit did not work that smoothly, because even when no one touches the sensor, it still has an output around 400, and the numeric changes from the sensor is not that big. One potential way to improve the circuit would be the transform the sensor output. For example, we could try to subtract the base number (400) from the output, and then square (or take absolute number of) the result, and then map the numbers correspondingly.

const int sensor_pin = A2;

const int light_pin = 2;

int sensor_value = 0;

int brightness = 0;

void setup() {

  Serial.begin(9600);

  pinMode (light_pin, OUTPUT);
}

void loop() {

  sensor_value = analogRead(A2);
  
  Serial.println(sensor_value);
  
  sensor_value= constrain(sensor_value, 500,600);
  
  brightness = map(sensor_value, 500, 600, 0, 255);

  analogWrite(light_pin, brightness);

  delay(100);
} 

After-class Assignment: Wearable Device

After brainstorming for quite a long time, Annika and I wanted to make something that would to some extent limit human perception. However, due to the very limited resources, as we had nearly no materials, we were not able to build exactly what we have in mind. At last, we built two locks, one that locks human movement around neck and arms, the other that locks human visions.

  

We first gathered around all the materials we had, which were some feathers, tapes, a plastic bottle, and some chopsticks. After exploring some potential ideas, we decided to make full use of the plastic bottle. We cut the two ends of the bottle, then used fire to bend the plastic, so that it looks a little bit like an octopus.  By doing so, we built our first lock, a monocle-like lens. When people look through this lens, due to its long width, he or she loses all the afterglow of what he or she sees, and thus forced to focus on what is right in the center of the cause. In this way, this lens locks human vision to only the center part.

In addition to the lens, we made a second lock, which restricts people’s physical movement. Inspired by ancient Chinese shackles, we used sticks and tape to make this “lock”. We didn’t want the device to become a physical torture, so we made the lock very loose to make it easier to wear. When wearing this lock, the physical distance between one’s neck and wrists are fixed, so that people cannot easily move their heads or arms in any direction.

We want to emphasize human attention to other people, or other objects. Although we would normally look at the exact target when we wanted to focus on something, we would actually be easily distracted by all our surroundings, such as movements you captured in your afterglow sight, the other human or even the pen in your hand. We built these two locks trying to help people get their attention back, by limiting their vision and physical actions. The yellow-black tape was widely used in crime scenes to show alarms and convey the idea of forbidden and limits. We adapted such concepts of limitation into our design of the locks. We hope that through this feeling of limitation, people would reconsider their attention with the outside world and with their inside concentrations. 

Soft Switch

I first built the circuit on breadboard to test if everything is working, including the button, the battery and the LEDs. Although I used two LEDs on the breadboard by connecting them in parallel, I used only one LED on the soft circuit because I ran out of conductive wire.

Then, I moved the circuit onto one piece of fabric. In the process, I met several problems and difficulties. The first problem was to make a small pocket for holding the battery. In order to have better connection, I decided to use conductive fabric for both the front and the back of the pocket. So that both the negative and the positive sides of the battery have conductive fabric. I hoped that having a larger conductive area will make the battery easier to be connected to the circuit. However, the problem of having larger conductive space was to avoid short-circuit. Since if the two conductive fabric touches each other, it forms a short-circuit. Therefore, I tired to make one side of the conductive fabric significantly smaller than the other side, so that when the battery is inside the pocket, two conductive fabric cannot touch each other.

  

The second problem was with the ending knot after sewing. I was not very familiar with making the ending knot and I found some of those knots dissipated after some time. Therefore I had to sewing those loose ends again and making one other ending knot after sewing. So the back side of my soft fabric was not very good-looking, it is covered with many failed knots.

The third problem was working with conductive wire. The conductive wire is thicker and harder, making it much harder to deal with compared with normal wire. Also, conductive wire often tangle themselves together, making sewing more difficult.

And the biggest difficulty I met in building the soft circuit was when the second and the third problems came together. One ending knot of conductive wire dissipated right after I cut off the extra wire. The wire was so short and so thick that I could not make another knot from it. And I have to secure its position so that the loose end would not touch other conductive wire and form a short-circuit. Therefore, I used normal wire and sew the loose end tightly in its original place, which left an ugly scare on my fabric circuit.

  

In the end, I have made this simple soft fabric where the LED with light up then the battery is inside the little pocket and the two button parts touch each other. With some limitation with materials and tools, I did not make fancy decisions for the switch. And though battery pocket is not working perfectly that I sometimes need to adjust its position to close the circuit, I enjoyed the process of hand making this circuit and practiced a lot about working with conductive wire.

  

Reading Reflections

1. What is fashion for you? and why are you interested in fashion?

To me, I would regard fashion as innovations that people can relate to. Saying innovation means that they have some distinguishable features from old trends, that are newly created, or taking from other aspects that have never been applied to this field before. As for relate to, I mean that people can generate thoughts towards to it. Thoughts can either be regarding the piece as beautiful and love it, or evoke a certain thinking towards the concept and idea behind the piece. I am interested in fashion because it is one commonly used word and idea in our daily life, and I would like to explore more about this idea, to learn through what is fashion, and how can I be part of this fashion.

2. What kinds of things do your clothing say about you and your values?

I think one common feature my clothing shares is to be unisex, clothes that does not heavily represent male or female features. I like to wear clothes that both man and woman can wear.I believe such clothing pattern comes along with my gender values that men don’t need to be masculine and women don’t need to be sexy. I do not want to be regarded as a man only of masculine, so I tend to choose clothes that are not in the most common male stereotypes.

3. What are your main learnings and take aways from the readings?

One of the most important take aways from the readings is the idea conveyed by Fred Davis that clothing are difficult to understand, and within different contexts the same cloth could have totally different meanings. This idea promotes me to rethink about my understanding about clothes and especially about those clothes that I could not appreciate before. I would now try to find out and understand the context behind the piece of cloth, and try to related these two together to value and appreciate the clothing. The reading widens my understanding and judgement to the basic concept of clothing.