For this lab, I wanted to create an optical illusion through the movement of the DC motor. I stuck a round shaped piece of stiff paper and tried out several designs. What I wanted was an outward moving spiral and I think my design is right because I can kind of see it when the motor is turning off but otherwise, the motor spins too fast for the effect to be visible to the naked eye. I settled with a design which too demonstrates how perception works and what we see may not be what is.

Components

• Arduino Uno
• breadboard
• 1 DC motor
• 1 Transistor
• 1 Diode
• 1 resistors (one 1KΩ)
• 1 potentiometer
• battery pack
• two AA batteries
• jumper wires

Arduino Code

/*
* one pot fades one motor and LED
*/

int potPin = A0; // select the input pin for the potentiometer
int motorPin = 9; // select the pin for the Motor
int val; // variable to store the value coming from the sensor
void setup() {
pinMode (potPin, OUTPUT);
Serial.begin(9600);
}
void loop() {
val = analogRead(potPin); // read the value from the sensor, between 0 – 1024
Serial.println(val);
analogWrite(motorPin, val/4); // analogWrite can be between 0-255
}

Description

I attached my FSR to a pair of tongs and through the visualization, you can see how much force you’re using to hold/pick up an object. My visualization makes use of color, size and speed to demonstrate changes in force applied. Squared move diagonally across the screen and as the pressure increases, so does their speed and they grow in size too. At maximum force, the background color  becomes a bright green and is meant to grab the user’s attention or alert her.

Components

Arduino

Bread board

1 10 kΩ resistor

Jumper cables

1 FSR

Tongs

Arduino code

int fsrAnalogPin = 0; // FSR is connected to analog 0
int LEDpin = 11; // connect Red LED to pin 11 (PWM pin)
int fsrReading; // the analog reading from the FSR resistor divider
int LEDbrightness;

void setup(void) {
Serial.begin(9600); // We’ll send debugging information via the Serial monitor
pinMode(LEDpin, OUTPUT);
}

void loop(void) {
fsrReading = analogRead(fsrAnalogPin);
// Serial.print(“Analog reading = “);
// Serial.println(fsrReading);

// we’ll need to change the range from the analog reading (0-1023) down to the range
// used by analogWrite (0-255) with map!
LEDbrightness = map(fsrReading, 0, 1023, 0, 255);
// LED gets brighter the harder you press
analogWrite(LEDpin, LEDbrightness);

delay(100);
Serial.println(fsrReading); // for processing
}

Processing code

/* PROCESSING SKETCH
* FSR Visualization – Moving squares
* Reema Naqvi
*/

import processing.serial.*;
// Change this to the portname your Arduino board
String portname = “/dev/cu.usbmodem1411”; // or “COM5″
Serial port;
String buf=””;
int cr = 13; // ASCII return == 13
int lf = 10; // ASCII linefeed == 10

int serialVal = 0;
int rgbValr;
int rgbValg;
int rgbValb;
int moveX = 0;
int moveY = 0;
void setup() {
size(1200,700);
frameRate(20);
smooth();
background(0, 10, 20);
noStroke();
port = new Serial(this, portname, 9600);
}

void draw() {
// erase the screen

rgbValr = 255-serialVal/4;
rgbValg = 255-serialVal/9;
rgbValb = 255-serialVal/4;
background(rgbValr, rgbValg, rgbValb);

fill (255,0,190);
rect(moveX, moveY, serialVal/20 , serialVal/20);
moveX = moveX+serialVal/30;
moveY = moveY+serialVal/30;
if (moveY >= height) {
moveY = 0;
moveX = 0;
}
if (moveX >= width) {
moveX = 0;
moveY = 0;
}

rect(moveX+300, moveY, serialVal/15 , serialVal/15);
moveX = moveX+serialVal/30;
moveY = moveY+serialVal/40;
if (moveY >= height) {
moveY = 0;
moveX = 0;
}
if (moveX >= width) {
moveX = 0;
moveY = 0;
}

rect(moveX+600, moveY+100, serialVal/10 , serialVal/10);
moveX = moveX+serialVal/30;
moveY = moveY+serialVal/40;
if (moveY >= height) {
moveY = 0;
moveX = 0;
}
if (moveX >= width) {
moveX = 0;
moveY = 0;
}

rect(moveX – 200, moveY+300, serialVal/40 , serialVal/40);
moveX = moveX+serialVal/30;
moveY = moveY+serialVal/40;
if (moveY >= height) {
moveY = 0;
moveX = 0;
}
if (moveX >= width) {
moveX = 0;
moveY = 0;
}

rect(moveX-100, moveY+400, serialVal/25 , serialVal/25);
moveX = moveX+serialVal/30;
moveY = moveY+serialVal/40;
if (moveY >= height) {
moveY = 0;
moveX = 0;
}
if (moveX >= width) {
moveX = 0;
moveY = 0;
}

rect(moveX+1150, moveY+400, serialVal/8 , serialVal/8);
moveX = moveX+serialVal/30;
moveY = moveY+serialVal/40;
if (moveY >= height) {
moveY = 0;
moveX = 0;
}
if (moveX >= width) {
moveX = 0;
moveY = 0;
}

rect(moveX, moveY+200, serialVal/15 , serialVal/15);
moveX = moveX+serialVal/30;
moveY = moveY+serialVal/40;
if (moveY >= height) {
moveY = 0;
moveX = 0;
}
if (moveX >= width) {
moveX = 0;
moveY = 0;
}

rect(moveX+1000, moveY, serialVal/20 , serialVal/20);
moveX = moveX+serialVal/30;
moveY = moveY+serialVal/30;
if (moveY >= 300) {
moveY = 0;
moveX = 0;
}
if (moveX >= width) {
moveX = 0;
moveY = 0;
}
rect(moveX+600, moveY+400, serialVal/8 , serialVal/8);
moveX = moveX+serialVal/30;
moveY = moveY+serialVal/40;
if (moveY >= height) {
moveY = 0;
moveX = 0;
}
if (moveX >= width) {
moveX = 0;
moveY = 0;
}

}

// called whenever serial data arrives
void serialEvent(Serial p) {
int c = port.read();
if (c != lf && c != cr) {
buf += char(c);
}
if (c == lf) {
serialVal = int(buf);
println(“val=”+serialVal);
buf = “”;
}
}

Components

• 1 Arduino
• 1 breadboard
• 3 LEDs (red, green, blue)
• 3 potentiometers
• 3 225-ohm resisters
• wires

For this lab/hw, I controlled the brightness of each LED with a different potentiometer.

Code
// initialize pot pins
int potPin1 = A0;
int potPin2 = A2;
int potPin3 = A3;

// set pot values;
int potV1 = 0;
int potV2 = 0;
int potV3 = 0;

// initialize leds
int blueLed = 6;
int redLed = 9;
int greenLed = 11;

void setup() {
Serial.begin(9600);
// declare the led pin as an output:
pinMode(blueLed, OUTPUT);
pinMode(redLed, OUTPUT);
pinMode(greenLed, OUTPUT);
}

void loop() {
potV1 = analogRead(potPin1);
potV2 = analogRead(potPin1);
potV3 = analogRead(potPin1); // read the pot value
analogWrite(blueLed, potV1/4);
analogWrite(redLed, potV2/4);
analogWrite(greenLed, potV3/4);

delay(10); // wait a bit, for serial data
}