Arduino Code
#include <CapSense.h>

void setup()
{
sensorDefinitions[0] = &note1;
sensorDefinitions[1] = &note2;
sensorDefinitions[2] = &note3;
sensorDefinitions[3] = &note4;
sensorDefinitions[4] = &note5;
sensorDefinitions[5] = &note6;
sensorDefinitions[6] = &note7;
sensorDefinitions[7] = &note8;
sensorDefinitions[8] = &note9;
sensorDefinitions[9] = &note10;
Serial.begin(9600);
}

void loop()
{
start = millis();
for (i=0;i<NUMBER_OF_SENSORS;i++)
{
sensor = (*sensorDefinitions[i]).capSense(10);
if (sensor > 100)
sensorArray[0][i]=1;
else
sensorArray[0][i]=0;
}
sendArray();
}

void sendArray ()
{
for (i=0;i<ARRAYX;i++)
{
for (j=0;j<ARRAYY;j++)
{
Serial.print(sensorArray[i][j]);
Serial.print('\t'); //tab character
}
Serial.print('\n'); //new line c
}
Serial.print('!');
}

Processing Code

/**
* Adopted by High-Low Tech from SinePiano by Dan Ellis, dpwe@ee.columbia.edu
*/

void draw()
{
background(0);
stroke(255);
// draw the output waveforms, so there's something to look at
for(int i = 0; i < out.bufferSize() - 1; i++)
{
float x1 = map(i, 0, out.bufferSize(), 0, width);
float x2 = map(i+1, 0, out.bufferSize(), 0, width);
line(x1, 50 + out.left.get(i)*50, x2, 50 + out.left.get(i+1)*50);
line(x1, 150 + out.right.get(i)*50, x2, 150 + out.right.get(i+1)*50);
}
}

void serialEvent (Serial myPort) {
String inString = myPort.readStringUntil('!');
String[] incomingArrayRows = splitTokens(inString, "\n");
for (int i=0;i<ARRAYX;i++)
{
String[] incomingArrayEntries = splitTokens(incomingArrayRows[i], "\t");
for (int j=0;j<ARRAYY;j++)
{
sensorArrayOld[i][j] = sensorArray[i][j];
sensorArray[i][j]=int(incomingArrayEntries[j]);
}
}
float pitch = 0;
for (int i=0;i<ARRAYX;i++)
{
for (int j=0;j<ARRAYY;j++)
{
if (sensorArray[i][j]>0 & (sensorArray[i][j]!=sensorArrayOld[i][j]))
{
pitch = noteArray[i][j];
newNote = new MyNote(pitch, 0.3);
}
}
}
}

// This also handles stopping this oscillator when its level is very low.
if (level < 0.01) {
out.removeSignal(this);
}
// this will lead to destruction of the object, since the only active
// reference to it is from the LineOut
}

}

As part of my final project, and in working from the same warp as the Thermochromic Upholstery,  I was interested in developing a series of textiles whose sensing capabilities are inherent in the construction of the material. In the final working sample, I used a construction called deflected double weave, which allows for areas of conductive warp and weft to ‘float’ over each other instead of weave together.r. By inserting Velostat between these layers, a series of pressure sensors was created. For the descriptions in Grasshopper, I used Firefly to simulate when pressure is applied to the material. Firefly is a Grasshopper plug in which links modeling and Arduino, allowing for interactive prototyping.

     

Woven Pressure Sensor - Conductive thread was used in the warp and weft to create circuits.

FURTHER EXPLORATION

I invision that this process could be reproduced on a very small scale, allowing for a material with dense sensing points.Within this project, I wanted to address how architects and designers could use computation to design and test materials within their own practice. To explore this theme, I am developing descriptions in Grasshopper with Firefly to simulate when pressure is applied to the material. I hope to continue these explorations with other materials and types of sensors.

Rendering of Woven Construction

Final Presentation

Videos:

Winding a Conductive Warp

Pressure sensor simulation

First Simulation In Grasshopper/Firefly

About Double Weave: Double Weave PDF

Original Proposal MaterialMaker_3

Grasshopper Annotated

According to the Labor Department’s Workplace projections for 2018, nine of the 10 fastest-growing occupations that require at least a bachelor’s degree will require significant scientific or mathematical training. Some of the largest increases will be in engineering- and computer-related fields in which women currently only hold one-quarter or fewer of the jobs. Gender differences in self-confidence in STEM subjects start in middle school and increase thereafter. Thus the years from middle school to high school are the prime time to initiate interest for females in the STEM subjects. Researches also show that cultural factors, rather than a lack of aptitude or intrinsic interest make subjects such as computer science or engineering less appealing to young women. For my final project, I hopes to create a craft kit that will engages young women in computing/engineering projects that are more relevant to them. It will serve as a non-intimidating channel for young women to gain hands-on experience while building something beautiful, expressive, and useful that they can share with their family and friends.

Process

I first researched on current kits on the market. There is a clear gap in technology-based craft kits for young women.

Since clay is easily manipulated and familiar to the target audience. Clay would be a great material for a craft kit.

I designed four mini projects for this kit:

I have documented the steps in how to make three projects. I envision this would be the way the instructions will look in a real craft kit.

Thermochromic Brooch

Picture of the final product

List of materials needed

Step-by Step Instructions

A pre-circuited base would come with each kit, this would allow the user to create interesting projects without having equipments such as a solder.

Demo

Thermochromic Brooch 2

Picture of the final product

List of materials needed

Step-by-Step Instructions

Demo

Pressure sensor necklace

Picture of the final product

Step-by-Step Instructions

Comparison of modeling materials used

Note that the thermochromic clay is made by mixing thermochromic powder and regular clay. Both types of clay mixed easily and well with the thermochromic powder. It’s an activity that children can undertake on their own.

Comparison of conductive materials used

The main conductive materials used are:

Conductive thread: conductive thread worked best in both creating jewelry and creating heat in the thermochromic clay. It used the less power compared with conductive fabric. It created more heat compared to copper tape. Conductive ink on paper was also considered by painting on a piece of paper and inserting the paper into the clay. The procedure was difficult and was abandoned. In the future, I plan to also experimenting with painting on dried clay. However, since conductive silver ink is expensive, it may not be the best option for the kit.

Conductive clay: conductive clay was used in the brooch project. It was created by mixing carbon powder with clay. The clay was fairly conductive when dried, It heated up and cooled the crystal thermochromic ink very quickly. This is an area I want to explore more and create more projects. Some downsides are that the clay is black in color, thus may not be appealing when not used with crystal ink. The clay is also brittle and cracks easily. More experimentation with percentage of carbon powder and clay needs to be documented to derive the best combination.

Conclusion

The concept of my final project is a technology-based activity kits that user can purchase and be able to create all the projects on their own. Through learning about computing and engineering in an informal and hands-on manner, this craft kit could contribute towards bridging the gender gap in STEM studies. More experimentation and more relevant lessons need to be developed to help achieve the craft kit’s mission.

Going forward I plan to carry this idea further and develop a business plan next year. A prototype of the product is shown below.

Modular Pneumatic Façade System (MPFS), attempts to juxtapose key characteristics of biological design (modularity, robustness, homeostasis, and adaptive) with smart technologies (material, sensor, actuation, and control) in order to create a kinetic façade system that respond and interact with its environment in real-time.

   Similar to how an independent cell coordinates with each other to undergo certain tasks in multicellular systems in nature, the MPFS is consisted of autonomous modules that collectively achieve assigned functions. Each MPFS module is integrated with its own sensor, actuation, and control components which contribute to the robustness of the system as well as allow it to adapt to external stimulus. As an aggregated system, MPFS’s has potentials to initiate emergent behaviors at the global level due to the chain reaction between individual modules at the local level. Inspired by the hydro skeletons and muscular hydrostats in nature (e.g. elephant trunk, starfish, octopus arm, etc.), the kinematics are based on the combination of elastic material body actuator and pneumatic pressure feedback system.

Valve and Pneumatic Pump connection through Microcontroller

Final Module Prototype

Final Presentation
Modular Pneumatic Façade System (MPFS) Final Presentation

Question:What role can textiles and interiors play in informing us about exterior conditions?
Goal: To create a series of textiles that are augmented by exterior conditions like weather or temperature.

Overview: Over the past few weeks we have conducted a series of experiments consisting of different types of woven and knit thermochromic textiles. These included, dyeing yarn and piece dyeing fabric, embroidering patterns with steel thread, knitting in conjunction with computer generated patterns, felting, and weaving with conductive yarn (steel) in the warp of the weave.

We intended to affect the fabrics with outside data such as temperature. This upholstered stool is a small example to proove our concept. These fabrics may be better implicated as wall coverings, widow treatments, or as decorative pieces.

Videos:

Winding a Conductive Warp

Thermochromic Testing on Conductive Upholstery

Thermochromic Upholstery Activated by Temperature Data Feed

Presentation Link: ThermochromicTextilesPresentation

Code:

Arduino:

int inComingCharacter = 0;         // incoming serial byte

//int inComingData[10] = {‘A’};

int inComingNumber;

long i;

void setup(){

Serial.begin(9600);

pinMode(13, OUTPUT);

pinMode(5, OUTPUT);

pinMode(6, OUTPUT);

pinMode(9, OUTPUT);

}

void loop()

{

// if we get a valid byte, read analog ins:

if (Serial.available() > 0) {

inComingNumber = Serial.read();

Serial.write(inComingNumber);

digitalWrite(13, HIGH);

delay(100);

if (inComingNumber > 29 && inComingNumber < 40){

digitalWrite(5, HIGH);

digitalWrite(6, LOW);

digitalWrite(9, LOW);

}

if (inComingNumber > 39 && inComingNumber < 50){

digitalWrite(6, HIGH);

digitalWrite(5, LOW);

digitalWrite(9, LOW);

}

if (inComingNumber > 49 && inComingNumber < 60){

digitalWrite(9, HIGH);

digitalWrite(5, LOW);

digitalWrite(6, LOW);

}else{

digitalWrite(13, LOW);

}

}

}

Processing:

import processing.serial.*;

String[] temp;

int index = 0;

Serial myPort;                       // The serial port

int[] serialInArray = new int[3];    // Where we’ll put what we receive

int serialCount = 0;                 // A count of how many bytes we receive

boolean firstContact = false;        // Whether we’ve heard from the microcontroller

void setup(){

temp = loadStrings(“positions_2.txt”);

println(Serial.list());

myPort = new Serial(this, Serial.list()[0], 9600);

}

void draw() {

if (index < temp.length) {

String[] pieces = split(temp[index],’\t’);

println(“Sent: ” + pieces[0]);

myPort.write(int(pieces[0]));

}

// Go to the next line for the next run through draw()

index = index + 1;

delay(5000);

}

void serialEvent(Serial p)

{

while (p.available() > 0) {

println(“received: ” + p.read());

}

}

Nitinol, an alloy of nickel and titanium, has some wild phase-change properties. Beneath a certain threshold temperature, the atoms align in such a fashion, as to make the metal soft and ductile. Once heated, though, the alloy moves out of this martensite phase, and into a rigid austentite phase. “Training” nitinol sets this austentite phase, allowing the metal to return to a specific configuration whenever the metal is heated.

Training nitinol is relatively simple. You need:

1. An accurate furnace, capable of holding and mainting 500C.
2. Nitinol. Available from a number of sources. Our’s is from Dynalloy Corp.
3. Water, for quenching the heated wire and fixing the austentite phase.
4. Heat-safe jigs, for holding the bent nitinol in shape, while it is being heated.

The process itself, is not much more difficult:

1. Bend untrained nitinol to desired shape and fix to jig.
2. Place in furnace at 500C for 10 minutes (this might require some tweaking).
3. Quench in water, to cool nitinol quickly.

At that point, the nitinol is ready for use. Care should be used in taking the newly-trained wire off of the jig, as it is easy to put permanent crimps in the wire, regardless of the training.

So! Onward.

Here’s the furnace that I used. It really well, though it took nearly two hours to get up to temperature (and about that much to cool down, too).

A variety of trained and untrained nitinol. I mostly worked with .01″ untrained wire, though I did experiments with finer stuff as well. For actuating paper, though, you need something a little beefier

The jig is particularly important. While the nitinol is being heated to 500C, it likes to jerk around–so to ensure that the ‘fixed’ shape is what you expect, it must be firmly fastened. I looked to Marcelo Coehlo’s Media Lab thesis, Materials of Interaction, 2008, where he uses a reconfigurable system of nuts and bolts.

I cut the jig on the waterjet downstairs from some scrap aluminum, but that’s just a bonus. You could knock some holes in a piece of metal with a power drill.

Fierce action on the waterjet. It takes just a couple of minutes to cut something small and simple out of 1/8″ scrap aluminum stock.

I tapped holes in the resulting jig, to provide a firm seat for the bolts. The nuts themselves were tightened tightly down around the nitinol strands. Note, here, that though the strands are separated, they don’t have to be. You’re just interested in heating the nitinol evenly–their relative conduction doesn’t matter, so the wires can touch. This is true if you’re planning on heating the allow passively as well, of course. If you’re going to be running current through the stuff, though, that’s a different story. You’ll need to avoid short circuits where the wires may touch.

Spring are a really useful shape, as they contract a great deal (I’ve got some videos later). By fixing the wire at each of the nut with a bolt, and then carefully wrapping the nitinol into the threads of the screw, you can get a lovely, regular spring out.

Placing the wired-up jig in the furnace. I started out wearing gloves and paranoid about the heat, but these little kitchen tongs did the job reasonably well. 500C is hot, though, 932F, so serious precautions should be the order of the day. I am bad at that sometimes.

Once the jig is removed, it is quenched in a bucket of water. It cools down quick, but sends out a pleasantly impressive sputter.

This is what you get out of it. A mad-cap tangle. This bit is actually pretty smooth, but you can see some of the kinks that are characteristic in the martensite phase.

You can see this fellow twitching around, here, though not really in a useful fashion. The loops and such that are formed as the nitinol is heated into the stiff austenite phase, are the points on which it was looped around the nuts on the jig.

While the heat gun works well, it doesn’t apply even heat–and at any rate, it’s impractical to blast every project with hot air just to get the wire to actuate. Here, I’m experimenting with a DC power-supply and about an amp of current on a longer length of wire. You have to push the voltage up there to actuate a piece of wire this long.

This is a nitinol spring relaxed and contracted under about an amp of current. Using power resistors that can handle more current than the 1/4 watt little guys, allows you to use really short lengths of nitinol without frying a length of wire this short (about an inch). You can see the dramatic motion here, somewhere about 50% of the overall length under a light load.

The next step: seeing how these play around when attached to paper. My original plan was to make a sheet of paper, and embed the nitinol wires within them–but experiments with bent pieces of wire were not particularly successful under load. Having a wire fold, say, into a triangle, is not as strong as a spring, as all of the actuation force is focused on three small corners, as opposed to a full length of wire. Circles, ellipses, and other shapes may perform better, but would require another jig system.

This miura fold has a spring attached to the back, which gives it reasonably dramatic motion–at least by the limited standards of flexinol. The kind of lever-engineering needed to get good motion out of flexinol is not used here.

This is what the rear looks like.

Finally, putting together an analog capacitive sensor (using a relaxation oscillator and code that counts a series of wave samples), to get a touch-sensitive actuating sheet. I’d like to implement this in a more elegant and intuitive way, but it’s a start! In the background, you can hear Joe P. rocking out on http://synth.media.mit.edu/.

Here’s a link to the final class presentation (PDF), given on December 13, 2011.