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---
author: Fred Cahill, Shawn Nock
institute: Unlondon Digital Media Assoc.
title: Introduction to Art Engineering
subtitle: Medway High School
lang: en-CA
colorlinks: true
...
# Goals
## Art Engineering
- Science, technology, engineering and maths; in service of Art.
- Allows unprecedented interactivity
- Reach Kids, non-traditional art audiences
- Opens doors to new funding sources, non-traditional gallery space.
## Unlondon
- 121Studios: Coworking for Creatives
- Unlab: Hackerspace
- Events: STEAM Outreach & Edu., ExplodeConf, Nuit Blanche
## Shawn: Day Job
Freelance Engineer, Father
- Indoor location tracking w/ Bluetooth
- Keychain / Fitness Band Widgets
- Joystick for VR
- Remote Controls
- Internet of S*#t
## Shawn: The Fun Stuff
Hacker, Church of the Weird Machine, Odd Duck
\begin{columns}[c]
\column{0.50\textwidth}
\begin{itemize}
\item Arduino compatible implant
\item EEG Games / Toy Hacking
\item Brain Stimulation
\item Be Weird, Make Weird, Have Fun!
\item Bad at "Art"
\end{itemize}
\column{0.50\textwidth}
\begin{center}
\includegraphics[width=0.95\textwidth]{images/timbo.jpg}
\vspace{5mm}
\includegraphics[width=0.95\textwidth]{images/circadia.jpg}
\end{center}
\end{columns}
## @scanlime: Micah Elizabeth Scott, Art Engineer
> "...she explores the boundaries between technology, society, and creative
> expression, using her unique perspective to try and help illuminate
> what makes us human."
[^1]
- [Eclipse](https://www.youtube.com/watch?v=bqGXC6AGlWw)
- [Forest](https://www.youtube.com/watch?v=6HcIPMVUezI)
- [Zen Photon Garden](http://zenphoton.com)
[^1]: Micah's Portfolio Website: [misc.name](http://www.misc.name)
## @kimalpert: Kim Alpert, Aesthetic Engineer
> "With a background in fine art, world music, and carpentry, Kim Alpert
> brings an attention to detail and diverse style to her work."
[^2]
- [Bodyphonic @ National Music Center, Calgary](https://vimeo.com/154004279)
[^2]: Kim's Portfolio Website: [http://aestheticengineer.com](http://aestheticengineer.com)
## Fred: The Vital Info
## Electro Sideshow
\fullImage{images/fred/Electro Sideshow.jpg}
## World Record Tower
\fullImage{images/fred/world record tower for arduino
presentation.jpg}
## Roll Up the Cosmos
\fullImage{images/fred/roll up the cosmos for arduino presentation.jpg}
## Lumarca
\fullImage{images/fred/lumarca for arduino presentation.jpg}
## Knexhibitions
\fullImage{images/fred/knexhibitions for arduino presentation.jpg}
## Canon
\fullImage{images/fred/canon for arduino presentation.jpg}
# What's in your kit?
## Kit Contents
- Arduino Uno R3 Clone
- Solderless Breadboard
- Connecting wires
- LEDs
- Resistors, Potentiometer
- Buzzer
- IR Remote
- IR Receiver
## What is Arduino?
\begin{center}
$\mu$C + reset button + led + USB
\end{center}
It's a kit (on a board) with the bare minimum components to easily use the $\mu$C
hardware. They do the basic, boring design needed for any board, so users only
need to add the neat stuff.
<!-- ## Arduino UNO -->
<!-- The Arduino variety that we are using is the Arduino UNO. -->
<!-- - Processor: Atmel Atmega328p -->
<!-- - Memory: 2K RAM + 32K Flash -->
<!-- - FT232RL Logic-level Serial$\leftrightarrow$USB Chip -->
## Arduino Software
The Arduino folks also adapted an *Integrated Development Environment*
(IDE) to their boards. This IDE allows us to easily write programs for
their boards and then write the programs to the $\mu$C.
\Large Get the Arduino IDE:
[https://www.arduino.cc/en/Main/Software](https://www.arduino.cc/en/Main/Software)
## Installation
\Large Get installing
# Circuit Basics
## Current
Current is the flow of charge through a circuit. Conventionally we
think of this as happening from HIGH ($+$) to LOW ($-$)
## Voltage / Potential / Resistance
Voltage is how fast the current can move in the circuit. River
metaphor:
- current = flow rate: ($\si{\liter\per\second}$)
- voltage = change in height: ($\si{\meter}$)
Other devices in a circuit can impede / effect current flow. We'll
call them resistance(s).
<!-- ## Diode -->
<!-- \begin{columns}[c] -->
<!-- \column{0.50\textwidth} -->
<!-- \begin{itemize} -->
<!-- \item One way value for current\footnotemark[1] -->
<!-- \item LED $\equiv$ Light Emitting Diode -->
<!-- \item Band marks (-)\footnotemark[2] -->
<!-- \item Longer leg marks (+) -->
<!-- \end{itemize} -->
<!-- \column{0.50\textwidth} -->
<!-- \begin{center} -->
<!-- \includegraphics[width=0.75\textwidth]{images/diode.png} -->
<!-- \vspace{5mm} -->
<!-- \includegraphics[width=0.50\textwidth]{images/led.jpg} -->
<!-- \end{center} -->
<!-- \end{columns} -->
<!-- \footnotetext[1]{\tiny \url{https://learn.sparkfun.com/tutorials/diodes}} -->
<!-- \footnotetext[2]{\tiny \url{https://learn.sparkfun.com/tutorials/polarity/diode-and-led-polarity}} -->
<!-- ## Diode Problems -->
<!-- * Diodes don't limit current -->
<!-- * Diodes aren't perfect (some current turned to heat) -->
<!-- * Too much current = Too much heat = \large{BANG} -->
<!-- * How do we limit current? -->
<!-- ## Resistor -->
<!-- \begin{columns}[c] -->
<!-- \column{0.50\textwidth} -->
<!-- \begin{itemize} -->
<!-- \item \emph{Resist} the flow of current -->
<!-- \item Needed for LEDs: $\approx\SI{400}{\ohm}$\\ -->
<!-- (safe for $\le\SI{6}{\volt}$) -->
<!-- \item Button Pull-up/down: $\ge\SI{10}{\kilo\ohm}$ -->
<!-- \item Color coded, Google it -->
<!-- \end{itemize} -->
<!-- \column{0.50\textwidth} -->
<!-- \includegraphics[width=0.98\textwidth]{images/resistor.png} -->
<!-- \end{columns} -->
<!-- ## Ohm's Law -->
<!-- Ohm's Law relates current to potential and resistance. -->
<!-- $$ V = IR $$ -->
<!-- $$ I=\frac{V}{R} $$ -->
<!-- $$ R = \frac{V}{I} $$ -->
<!-- * V = Potential in Volts (\si{\volt}) -->
<!-- * I = Current in Amperes (\si{\ampere}) -->
<!-- * R = Resistance in Ohms (\si{\ohm}) -->
<!-- ## Ohm's Law: Example -->
<!-- The datasheet for an LED says that the maximum continuous current is -->
<!-- \SI{15}{\milli\ampere}. Your circuit operates at \SI{5}{\volt}\footnotemark[1]. How -->
<!-- big should your resistor be? -->
<!-- $$ \si{\ohm} = \frac{\SI{5}{\volt}}{\SI{0.015}{\ampere}} = 333.\overline{3}\si{\ohm} $$ -->
<!-- How much current for our *cheet sheet* value? -->
<!-- $$ \si{\ampere} = \frac{\SI{5}{\volt}}{\SI{400}{\ohm}} = \SI{12.5}{\milli\ampere} $$ -->
<!-- \footnotetext[1]{\tiny Actually, this calculation is inaccurate. LEDs will have a *forward voltage drop* of between \SI{300}{\milli\volt} and \SI{700}{\milli\volt} this should be subtracted from \si{\volt} above... but it's not critical.} -->
<!-- ## Buttons -->
<!-- - Buttons connect _or_ disconnect two wires/parts -->
<!-- - Momentary Switch: Normally Closed (NC), Normally Open (NO) -->
<!-- - Toggle Switch -->
## Circuits
A circuit is a completed loop from HIGH potential (voltage) to LOW,
which causes current to flow through some other components along the
way.
## Transducers {.fragile}
Often these *other* components are *transducers*, which convert
electrical energy into another sort of energy:
| |
-------|--------:
Speaker|Electrical $\rightarrow$ Sound
Microphone|Sound $\rightarrow$ Electrical
LED|Electrical $\rightarrow$ Light
LED|Light $\rightarrow$ Electrical
Piezoelectric|Electrical $\rightarrow$ Motion
<!-- ## Piezo Buzzer -->
<!-- - Piezoelectric elements change shape when voltage is applied -->
<!-- - Thin discs can be made to oscillate and create sound. -->
<!-- - Contains oscillator circuit -->
<!-- - Two connections: Vcc, GND -->
<!-- - Use a switch; connected = annoying tone, disconnected = glorious silence -->
## Power
The power supply provides the energy to drive the system.
Can be a:
* Voltage Regulator (converts one potential to another)
* Batteries
* Solar Panel
In our circuits, your laptop is converting it's power source to $\SI{5}{\volt}$ and
delivering power to our circuit via USB. You also have a battery pack
for computer-free shenanigans ($\SI{6}{\volt}$).
## $\mu$Controller
Microcontroller ($\mu$C) is a *processor*, *memory* and a few *peripherals* on a standalone
chip.
Processor
: is a group of transistors that understands a dozen or so
commands (ADD, SUB, JUMP..)
Memory
: a circuit that can hold values.
Peripherals
: Vary chip to chip, but often include timers, communications and
ADC, DAC.
Seems complicated, but really simple. They read a command from the
start of memory, then execute the command. At the end of the command,
read the next command from the next memory cell and
repeat^[some commands change the address of the next fetched command]
## Digital Signals
- Vcc: The power supply of the circuit elements
- GND: The reference voltage (usually \SI{0}{\volt})
- Connecting a part to Vcc = Logical 1
- Connecting to GND = Logical 0
- Connecting to Vcc & Ground is all the $\mu$C can do to talk to the world [^4]
[^4]: w/o fancy peripherals
## $\mu$C + Digital Signals as Switches
If one end of an LED is connected to ground, and the other end is
connected to a pin on a $\mu$Controller, then:
- If the $\mu$C sets the pin HIGH (Vcc, $\SI{5}{\volt}$) then current
will flow from the pin through the LED and turn it on.
- If $\mu$C sets the pin LOW (GND, $\SI{0}{\volt}) then the current
will not flow and the LED is off.
# Let's start programming
## Configure Arduino
\begin{center}
\includegraphics[width=0.98\textwidth]{images/arduino-board.png}
\end{center}
* Board: Arduino/Genuino UNO
* Port: \ldots
## Fetch the Class Code
- Download and extract: [https://nocko.se/assets/arduino-medway.zip](https://nocko.se/assets/arduino-medway.zip)
- File$\rightarrow$Preferences
- Browse for sketchbook
- Point it at the `sketchbook` subfolder of the extracted download
- You should now see a list of projects in the
File$\rightarrow$Sketchbook menu.
## The Code Environment
\begin{center}
\includegraphics[width=0.5\textwidth]{images/arduino-toolbar.png}
\end{center}
## Your first Program
~~~ C
/* the setup function runs once on reset / power */
void setup() {
/* set pin 13 as an output */
pinMode(13, OUTPUT);
}
/* the loop function repeats forever */
void loop() {
digitalWrite(13, HIGH); // turn on LED
delay(1000); // wait for a second
digitalWrite(13, LOW); // turn the off LED
delay(1000); // wait for a second
}
~~~
<!-- ## Buzzer: Hardware -->
<!-- \begin{center} -->
<!-- \includegraphics[width=0.98\textwidth]{images/buzzer-breadboard.png} -->
<!-- \end{center} -->
<!-- ## Buzzer: Software -->
<!-- ~~~ C -->
<!-- #define BUZZER 8 /* Make BUZZER same as pin 8 */ -->
<!-- void setup() { -->
<!-- pinMode(BUZZER, OUTPUT); -->
<!-- digitalWrite(BUZZER, HIGH); /* Turn off buzzer */ -->
<!-- } -->
<!-- void loop() { -->
<!-- digitalWrite(BUZZER, LOW); /* Turn on buzzer */ -->
<!-- delay(100); /* wait for 100ms */ -->
<!-- digitalWrite(BUZZER, HIGH); /* Turn off buzzer */ -->
<!-- delay(900); /* wait 900ms */ -->
<!-- } -->
<!-- ~~~ -->
<!-- ## Push Button: Hardware -->
<!-- \begin{center} -->
<!-- \includegraphics[width=0.98\textwidth]{images/buzzer-button-breadboard.png} -->
<!-- \end{center} -->
<!-- ## Push Button: Software (Part 1) -->
<!-- ~~~ C -->
<!-- #define BUTTON 7 -->
<!-- #define BUZZER 8 -->
<!-- int button_state = 0; -->
<!-- void setup() { -->
<!-- pinMode(BUTTON, INPUT); -->
<!-- pinMode(BUZZER, OUTPUT); -->
<!-- digitalWrite(BUZZER, HIGH); -->
<!-- } -->
<!-- ~~~ -->
<!-- ## Push Button: Software (Part 2) -->
<!-- ~~~ C -->
<!-- void loop() { -->
<!-- button_state = digitalRead(BUTTON); -->
<!-- if (button_state == HIGH) { -->
<!-- digitalWrite(BUZZER, LOW); -->
<!-- } else { -->
<!-- digitalWrite(BUZZER, HIGH); -->
<!-- } -->
<!-- } -->
<!-- ~~~ -->
# Add Some Parts
## Breadboard
![Breadboard](images/breadboard.png)\
- Connectors gently pinch component leads, wires.
- Have internal connections
## Power Up the Rails
We use the long rows to distribute power. The Arduino outputs
$\SI{5}{\volt}$ on the pin marked `5V`, the reference (GND) is marked
`GND`.
![Arduino + Breadboard](images/bb+uno.png)
## RGB LED
- Three LEDs in the same package.
- LEDs share the same `GND` ($-$) pin, one ($+$) side of each LED
- Connect `-` to negative rail, R, G, & B to pins 3,5, & 6 on Arduino
\centering
\includegraphics[width=0.60\textwidth]{images/bb+uno+led.png}
## RGB Blink, pt. 1
~~~ C
#define RED 6
...
#define DELAY_MS 1000
void setup() {
/* initialize digital pin functions */
pinMode(RED, OUTPUT);
...
~~~
## RGB Blink, pt. 2
~~~ C
/* turn the RED LED */
digitalWrite(RED, HIGH);
/* Do nothing for a while */
delay(DELAY_MS);
/* turn the LED off */
digitalWrite(RED, LOW);
delay(DELAY_MS);
/* Continue on to green LED */
digitalWrite(GREEN, HIGH);
...
~~~
# More Parts
## Potentiometer
*Puh - ten - she - ometer*
- *Pot* for short
- A Voltage Divider
- Potential at *Wiper* varies between the two terminals
## ADC: Analog to Digital Converter
- A peripheral of the $\mu$Controller
- Measures Potential, outputs a number
- In our case, $\SI{0}{\volt}\rightarrow0$ and
$\SI{5}{\volt}\rightarrow1023$
- A0-A5 pins on Arduino can be used
- Fun uses: Reading pot position, sampling audio, reading from sensors
## The Pot Hookup
![BB+Arduino+LED+Pot](images/bb+uno+led+pot.png)\
Connect center pin to `A0`, outer pins to ($+$) and ($-$) rails
## Pot Code, pt. 1: Variable
Declare a variable:
~~~ C
int delay_ms = 1000;
~~~
`<type> <name> [= <initial value>];` (value optional)
It's a name, like a preprocessor `#define`, but the value can change
at *runtime*
## Pot Code, pt. 2: ADC
`analogRead(`*pin*`)` returns the current state of the pin (0--1023),
it can be assigned to a variable.
~~~ C
void loop() {
delay_ms = analogRead(A0);
digitalWrite(RED, HIGH);
delay(delay_ms);
...
~~~
Each time through the loop, a new `delay_ms` value is read. Since the
subsequent delay calls use `delay_ms`, the blink rate changes.
# What else can you do with a light?
## Dimmer Code, pt. 1
New variable:
~~~ C
int brightness = 0;
~~~
## Dimmer Code, pt. 2
`analogWrite(`*pin*, *\<0--255\>*`)`, sets the *average* voltage to
$\SI{0}{\volt}$ @ 0 to $\SI{5}{\volt}$ @ 255.
~~~ C
void loop() {
brightness = analogRead(A0) >> 2;
analogWrite(RED, brightness);
...
~~~
## Bitwise Shift
Then number $100$ is the number $4$ in binary.
$0c100 << 1 = 0b1000 = 8$
$0b100 >> 1 = 0b10 = 2$
$0b10 >> 1 = 0b1 = 1$
Many $\mu$C do no have multiplication/division hardware, and they take
a lot of time and power to fake it. For powers of two, shifting is
faster/better.
## PWM
\begin{columns}[c]
\column{0.50\textwidth}
If $\mu$C can only output 0 and 1, how does "analogWrite" work?
\vspace{5mm}
We can turn the pin on and off very quickly and vary the *duty cycle*
(the percentage of time the pin is HIGH).
\column{0.50\textwidth}
\includegraphics{images/pwm.png}
\centering
\tiny Image courtesy of Arduino.cc
\end{columns}
# Remote Control
## IR Receiver
\centering
![IR Receiver](images/ir.png){ width=70% }\
\raggedright
Neat piece of kit. Internally demodulates IR signal @
$\SI{38}{\kilo\hertz}$ and outputs 16 bit code (unique to each button).
## Remote Control: Hardware Setup
\centering
![IR Remote Control Setup](images/bb+uno+led+pot+remote.png){ width=70% }\
\raggedright
`OUT` of IR Receiver connects to pin `2` of Arduino, `GND` (middle)
`GND` rail, remaining pin to `Vcc` rail.
## Remote Control: Code, pt. 1
Imports and libraries. You can include code from other files using
`#include`. These are often used to include library code, for example
below the `IRremote.h` file includes declarations that allow us to use
objects / methods from the IRremote library.
~~~ C
#include <IRremote.h>
#include "medway-remote.h"
~~~
## Remote Control: Code, pt. 2
~~~ C
bool power = false;
/* Initialize the irrecv part of the IRremote library */
IRrecv irrecv(IR_PIN);
decode_results results;
void setup() {
...
irrecv.enableIRIn();
}
~~~
## Bitwise AND
A function that compares the bit-by-bit two numbers. For each bit, it
returns 1 if both input bits are 1, else 0. Examples
- 5 & 1 = 1; 0b101 & 0b001 = 0b001
- 241 & 133 = 129; 0b11110001 & 0b10000101 = 0b10000001
Why use this? Setting or clearing ranges of bits.
0xF = 0b00001111, so anything `&` 0xF will clear any bits *left* of
the last four.
## Remote Control: Code, pt. 3
~~~ C
void loop() {
if (irrecv.decode(&results)) {
uint16_t resultCode = (results.value & 0xFFFF);
switch (resultCode) {
...
case ONE:
digitalWrite(RED, !digitalRead(RED));
break;
case TWO:
digitalWrite(GREEN, !digitalRead(GREEN));
break;
~~~
## Remote Control: Code, pt. 4
~~~ C
irrecv.resume();
~~~
This tells the IR Receiver library that we've processed the current
code, and it can provide (or wait) for the next one.
# Where to go next?
## Light Painting
Program a blink / fade (see Fade example in sketchbook) / colour
pattern into your led(s). Take a long exposure / multiple exposure
photograph as you move the project around the room.
## Buzzer
Hook up one end of the Piezo buzzer (black cylinder) to `GND` rail and
the other to a $\mu$Controller pin (sample code in remote
sketch). Turn on the buzzer and watch Fred and I squirm.
## Other sensors
Your kit also contains a photoresistor, try hooking it up to an ADC
pin. Your kit also has a modified LED that can act as a *flame
sensor*, it may be fun to play with\ldots.
## The End?
\begin{center}
\LARGE{Let's build some cool stuff!}
\end{center}
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