Iat 267 Final Quiz

Front 1

what does the Processing serial library allow?

Back 1

2 computers to send and receive data and gives you ability to communicate with microcontrollers (can be input or output)

Front 2

how to import the Serial library in processing?

Back 2

import processing.serial.*;

Serial myPort; // the serial port object

String[] portList = Serial.list(); //print out a list of available ports

println(portList);

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

Front 3

what data types can be sent to the serial port?

Back 3

byte, char, int, byte array, and String

Front 4

what are the four steps to using Serial library in Processing?

Back 4

1. load library

2. set portname

3. open port

4. read/write port (done in loop)

Front 5

Serial.read()

Back 5

reads incoming serial data

returns an int, the first byte of incoming serial data available (or -1 if no data is available)

Front 6

Serial.available()

Back 6

get the number of bytes (characters) available for reading from the serial port

this is data that has ALREADY arrived and is stored in the serial receive buffer

returns # of bytes available to read

Front 7

Serial.peek()

Back 7

returns the next byte (character) of incoming serial data without removing it from the internal serial buffer

Front 8

Serial.write()

Back 8

writes binary data to serial port

this data is sent as a byte or series of bytes; to send the characters representing the digits of a number use the print() function instead

Front 9

degrees of freedom

Back 9

rotation around X axis = pitch/tilt

rotation around Y axis = pan/yaw

rotation around Z axis = roll

left to right = X axis

up and down = Y axis

front to back = Z axis

Front 10

ranging sensors

Back 10

sense distance of a body from the sensor

sense movement in front of the sensor

MOST SENSORS range under 9 ft

for video tracking, range is adjustable depending on the zoom of the lens

Front 11

how do ranging sensors work?

Back 11

reads the distance from a target

work by sending out some reference signal

- light, magnetism, sound

measure the amount of energy that reflects off the target and compare it with the energy that went out

- difference converted into an electrical signal that can be read by a microcontroller

Front 12

detecting presence - foot switches

Back 12

work well within a small area

long strips of metal tape separated at intervals by foam tape

- when someone steps on sensor, foam tape compresses and metal strips touch each other

NEED TO BE ROBUST -> ppl weight

Front 13

detecting presence - photo electric switches

Back 13

a light beam hits a target sensor

when the beam is broken by a body passing between the sensor and light source, the switch is activated

Front 14

detecting presence - magnetic switches

Back 14

very thin pair of contacts in a projective housing

when they're exposed to a magnet, they're drawn together, closing the switch

Front 15

detecting presence - motion detectors

Back 15

respond to changes in the infrared light in the space

only react to change - will not respond if someone is in the room and standing still

Front 16

infrared (IR) sensors

Back 16

send out an infrared beam and read the reflection of the beam off a target

Front 17

ultrasonic sensors

Back 17

longer ranges than IR

send out a ping of ultrasonic sound and see how long it takes to bounce back

Front 18

what's bad about distance ranging sensors?

Back 18

don't operate uniformly at all distances

have zones in which they're most sensitive

(remember triangular)

need to use several sensors to cover a room

no two sensors operating at the same instant cuz interference

Front 19

accelerometer

Back 19

measure the change in speed of movement (acceleration)

typically have 2 or 3 axes of measurement

Front 20

video tracking

Back 20

video cameras:

dense array of thousands of photocells

can adjust lighting conditions

ability to separate incoming light by colour

pixel-by-pixel manipulation by computer

Front 21

what's the best solution for determining the details of a person's motion in a large space?

Back 21

camera on a ceiling

use software to look for X and Y position of any pixels that are a diff colour than the floor

Front 22

what are factors to consider when video tracking?

Back 22

you need strong and even lighting throughout the space with high contrast

make sure video camera can see infrared light

when using camera on ceiling, try to hang camera as high as possible

Front 23

what are 2 basic types of motion?

Back 23

linear motion

rotary motion - motors

Front 24

how to convert rotary motion into linear motion?

Back 24

use basic mechanics and simple machines

- lever

- pulley

- gear

- cam

- ratches

- linkages

Front 25

what are some characteristics of motors?

Back 25

rated voltage

current (stall or running?)

motor speed

position resolution (for servo/stepper motors)

torque

Front 26

stall current vs. running current

Back 26

stall - maximum current drawn when the motor is applying its maximum torque, either cuz it's being prevented from moving or cuz it can't accelerate given the load

running - all motors will require more energy to get them started than it takes to keep them running

Front 27

Servo attach (), write(), read()

Back 27

attach() reads the Servo instance on the pin passed in to the method

servo.attach(pin);

read() reads the current angle of the servo

Front 28

advantages of Servo motor

Back 28

easy to control and precise

servo reads amount of voltage passed in to determine how far to rotate within a limited range (usually 180)

Front 29

how computers identify objects?

Back 29

use information from sensors

optical recognition

radio frequency identification

Front 30

optical recognition

Back 30

can take many forms

- video colour tracking

- shape recognition

- barcode

identifiers

- colours

- shapes

- barcodes

Front 31

barcode recognition

Back 31

pattern of dark and light lines or cells used to encode an alphanumeric string

computer reads the barcode by scanning the image and interpreting the light and dark bands as 0 or 1

scanning done by camera or photodiode

Front 32

barcode vs. QR code

Back 32

1D barcode -> regular barcode

2D barcode -> Quick Response Code

- 2D matrix, more info density

Front 33

radio frequency identification (RFID)

Back 33

relies on tagging objects to identify them

RFID tags don't need to be visible to be read

RFID reader sends out a short range radio signal which is picked up by an RFID tag

the tag then transmits back a short string of data

Front 34

passive RFID

Back 34

tags contain an integrated circuit that has basic radio transceiver and non-volatine memory

powered by current that reader's signal induces in their antennas

received energy is just enough to power the tag to transmit its data once

Front 35

active RFID

Back 35

tag has own power supply and radio transceiver

transmits a signal in response to a received message from a reader

longer range, more expensive

Front 36

how to sense touch?

Back 36

force-sensitive resistors

thermistors

capacitance sensor

Front 37

force-sensitive resistors (FSR)

Back 37

convert mechanical force into electrical resistance

generally small, flat

Front 38

flex sensors

Back 38

look and work like FSR

vary resistance based on how much they're bent

flat plastic strip that can bend to 180 degrees

Front 39

pressure sensors

Back 39

measure pressure exerted by gas or fluid

most commonly used in pneumatic or hydraulic applications

Front 40

capacitance sensors

Back 40

sense electric change cuz human body always stores a small electric charge

can detect any object that carries a static charge

Front 41

touch interfaces/screens

Back 41

easiest way to connect touch with computer graphics

will only read contact at one point at one time

there's also multi touch touchpads

Front 42

other ways of sensing touch

Back 42

heat - you can detect if someone is touching an object by detecting an increase in heat using a thermistor

thermistors convert heat into electrical resistance

peltier junction = solid-state heat pump for creating hot or cold surfaces

Front 43

LED driver chip

Back 43

use it on arduino

control up to an 8x8 matrix of LEDs

use the Matrix library to control individual LEDs

Front 44

how to play sound with arduino

Back 44

piezospeaker

playing melodies with arduino makes use of PWM (digital pins 9, 10, 11)

piezos have polarity

Front 45

the simplest network

Back 45

one-to-one connection between 2 objects

before communication takes place, rules for communication have to be established

RULES = DIFFERENT LAYERS

Front 46

factors that influence communication between different machines and applications

Back 46

context

continuous, non-continous, asynchronous

the means of communication - how?

types of machines used - between what devices?

amount of data being exchanged

Front 47

benefits of communicating over a network

Back 47

enable your applications to work remotely

gather data from internet

network multiple devices and machines

Front 48

what are the layers of agreement in arduino to computer example?

Back 48

physical

electrical

logical

data

application

Front 49

physical layer

Back 49

how are the physical inputs/outputs of each device connected to the other

how many connections b/t 2 devices do you need

e.g. arduino receives data on pin 0 (RX) and sends it out on pin 1 (TX)

Front 50

electrical layer

Back 50

what voltage levels will you send to represent bits of your data?

e.g. arduino uses pulses of 0V and 5V to represent bits

Front 51

logical layer

Back 51

does an increase in voltage lvl represent a zero or a one?

e.g. 5V = 1; 0V = 0

Front 52

data layer

Back 52

what is the timing of the bits? are the bits read in groups of 8, 9, 10? are there bits at the beginning or end of each group to punctuate the groups?

e.g. data is sent at 9600 bits per second and each package contains 8 bits

Front 53

application layer

Back 53

how are the groups of bits arranged into messages?

what is the order in which messages have to be exchanged to get something done?

e.g. at the application layer, one byte is sent from PC to arduino and processed

Front 54

complex network

Back 54

collection of networks

a map is needed to keep track of objects/addressing scheme

Front 55

different types of network connections

Back 55

directly connected network

star network

ring network

Front 56

diff between hardware address and IP address?

Back 56

device's IP address can change when it's moved from one network to another

hardware address cannot change

hardware e.g. 00:11:24:9b:f3:70

IP e.g. 192.168.1.29

Front 57

what is a machine's address and why is it important?

Back 57

in order for an application on one machine to send a message to an application on another machine, the sending application must identify the receiving application

TO IDENTIFY, you need:

- name or address of host machine

- identity of receiving process on destination host

receiving process = application

Front 58

what are ports?

Back 58

computer has single physical connection to network and all data arrives through that

data may be intended for different apps on the computer so ports organize that

ports are identified by a 16-bit number

Front 59

3 parts of structure of a network application

Back 59

user interface - allows user to invoke and control app functionality

application logic - software code, processing instructions that provide functionality

application-level protocol - defines format and order of messages exchanged

Front 60

transport layer of a network

Back 60

responsible for making sure packets get to their destination

2 protocols used to handle transport of packets on the internet

- transmission control protocol (TCP)

- user datagram protocol (UDP)

Front 61

packets

Back 61

data broken into smaller pieces for easier sending

Front 62

what does a server do?

Back 62

it's the receiver of request sent by a client

it's passive, waits for requests

upon receipt of requests, processes them and then replies

usually accepts connections from large number of clients

typically does not interact directly with end-users

Front 63

user datagram protocol (UDP)

Back 63

LIGHTWEIGHT transport protocol with minimalist service model

CONNECTIONLESS, no handshaking before two processes start to communicate

UNRELIABLE data transfer service

- when a process sends a message into UDP socket, UDP provides no guarantee that the message will ever reach the receiving socket

no flow control mechanism so sending process can pump data into UDP socket at any rate

GOOD FOR REAL-TIME APPLICATIONS

Front 64

transmission control protocol (TCP)

Back 64

connection-oriented service

- client and server exchange control info before messages flow (handshaking!)

full-duplex connection so two processes can send messages to each other at same time

reliable transport service, delivers all messages sent without errors and in the proper order

Front 65

open sound control (OSC) protocol

Back 65

protocol for communication among computers, sound synthesizers, and other multimedia devices

use for: real-time sound and media processing environments, software synthesizers, web interactivity tools