The document outlines the fundamentals of IoT and M2M communication, detailing the networking of machines for remote monitoring and control, as well as various communication protocols. It highlights differences between M2M and IoT in terms of hardware emphasis, data collection, and interoperability, advocating for seamless communication among diverse devices and platforms. Additionally, it introduces Arduino programming basics, focusing on microcontroller types, setup, and programming to create interactive projects.

1. Fundamentals of IoT
Unit-II
4/29/2024 1

2. Syllabus
4/29/2024 2

3. Machine-to-Machine (M2M)
• Machine-to-Machine (M2M) refers to
networking of machines (or devices) for the
purpose of remote monitoring and control and
data exchange.
4/29/2024 3

4. Machine-to-Machine (M2M)
• An M2M area network comprises of machines (or M2M nodes) which have
embedded hardware modules for sensing, actuation and communication.
• Various communication protocols can be used for M2M local area networks such as
ZigBee, Bluetooh, ModBus, M-Bus, Wirless M-Bus, Power Line Communication
(PLC), 6LoWPAN, IEEE 802.15.4, etc.
• The communication network provides connectivity to remote M2M area networks.
• The communication network can use either wired or wireless networks (IPbased).
• While the M2M area networks use either proprietary or non-IP based communication
protocols, the communication network uses IP-based network.
4/29/2024 4

5. M2M Network
4/29/2024 5

6. M2M gateway
• Since non-IP based protocols are used within M2M area
networks, the M2M nodes within one network cannot
communicate with nodes in an external network.
• To enable the communication between remote M2M area
networks M2M gateways are used.
4/29/2024 6

7. M2M gateway
4/29/2024 7

8. Difference between IoT and M2M
Communication Protocols
• M2M and IoT can differ in how the communication between the machines or devices
happens.
• M2M uses either proprietary or non-IP based communication protocols for
communication within the M2M area networks.
Machines in M2M vs Things in IoT
• The "Things" in IoT refers to physical objects that have unique identifiers and can
sense and communicate with their external environment (and user applications) or
their internal physical states.
• M2M systems, in contrast to IoT, typically have homogeneous machine types within
an M2M area network.
4/29/2024 8

9. Difference between IoT and M2M
Hardware vs Software Emphasis
• While the emphasis of M2M is more hardware with embedded
modules, the emphasis of IoT is more on software.
Data Collection & Analysis
• M2M data is collected in point solutions and often in on-premises
storage infrastructure.
• In contrast to M2M, the data in IoT is collected in the cloud (can be
public, private or hybrid cloud).
4/29/2024 9

10. Difference between IoT and M2M
Applications
• M2M data is collected in point solutions and can be accessed by on-
premises applications such as diagnosis applications, service
management applications, and on premises enterprise applications.
• IoT data is collected in the cloud and can be accessed by cloud
applications such as analytics applications, enterprise applications,
remote diagnosis and management applications, etc.
4/29/2024 10

11. Communication in IoT vs M2M
4/29/2024 11

12. What is Interoperability?
– Interoperability is a characteristic of a product or
system,whose interfaces are completely understood,to
work with other products or systems, present or future,
in either implementation or access ,with out any
restrictions.
– Communicate meaningfully
– Exchange data or services
4/29/2024 12

13. Why Interoperability is Important in
Context of IoT?
– To fulfill the IoT objectives Physical objects can interact
with any other physical objects and can share their information
– Any device can communicate with other devices anytime from
anywhere
– Machine to Machine communication(M2M), Device to Device
Communication (D2D), Device to Machine Communication
(D2M)
– Seamless device integration with IoT network
4/29/2024 13

14. Why Interoperability is required?
– Heterogeneity Different wireless communication protocols such as
ZigBee (IEEE 802.15.4), Bluetooth (IEEE 802.15.1), GPRS,
6LowPAN, and Wi-Fi (IEEE 802.11)
– Different wired communication protocols like Ethernet (IEEE 802.3)
and Higher Layer LAN Protocols (IEEE 802.1)
– Different programming languages used in computing systems and
websites such as JavaScript, JAVA, C, C++, Visual Basic, PHP, and
Python
– Different hardware platforms such as Crossbow, NI, etc.
4/29/2024 14

15. Why Interoperability is required?
(Contd.)
– Different operating systems As an example for sensor node: TinyOS, SOS,
Mantis OS, RETOS, and mostly vendor specific OS
– As an example for personal computer: Windows, Mac, Unix, and Ubuntu
• Different databases: DB2, MySQL, Oracle, PostgreSQL, SQLite, SQL
Server, and Sybase
• Different data representations
• Different control models
• Syntactic or semantic interpretations
4/29/2024 15

16. Different Types of Interoperability?
–User Interoperability : Interoperability
problem between a user and a device
–Device Interoperability : Interoperability
problem between two different devices
4/29/2024 16

17. Example of Device and User
Interoperability
• Using IoT, both A and B provide a real-time
security service
• A is placed at Delhi, India, while B is placed at
Tokyo, Japan
• A, B, U use Hindi, Japanese, and English
language, respectively
• User U wants real-time service of CCTV
camera from the device A and B
4/29/2024 17

18. 4/29/2024 18

19. User Interoperability
The following problems need to be solved
• Device identification and categorization for
discovery
• Syntactic interoperability for device interaction
• Semantic interoperability for device interaction
4/29/2024 19

20. Device identification and
categorization for discovery
• There are different solutions for generating
unique address
– Electronic Product Codes (EPC)
– Universal Product Code (UPC)
– Uniform Resource Identifier (URI)
• IP Addresses IPv6
4/29/2024 20

21. Device identification and
categorization for discovery
• There are different device classification solutions
– United Nations Standard Products and Services
Code (UNSPSC) * an open, global, multi-sector standard
for efficient, accurate, flexible classification of products
and services.
– eCl@ss ** The standard is for classification and clear
description of cross-industry products
4/29/2024 21

22. Syntactic Interoperability for Device
Interaction
• The interoperability between devices and device
user in term of message formats.
• The message format from a device to a user is
understandable for the user’s computer.
• On the other hand, the message format from the
user to the device is executable by the device.
4/29/2024 22

23. • Some popular approaches are
• Service-oriented Computing (SOC)-based architecture
• Web services
• RESTfulweb services
• Open standard protocols such as IEEE 802.15.4, IEEE 802.15.1, and
WirelessHART*
• Closed protocols such as Z-Wave*
• *But these standards are incompatible with each other
4/29/2024 23

24. • Middleware technology Software middleware
bridge
• Dynamically map physical devices with different
domains
• Based on the map, the devices can be discovered
and controlled, remotely
• Cross-context syntactic interoperability
Collaborative concept exchange
• Using XML syntax
4/29/2024 24

25. Semantic Interoperability for Device
Interaction
• The interoperability between devices and device
user in term of message’s meaning.
• The device can understand the meaning of user’s
instruction that is sent from the user to the device.
• Similarly, the user can understand the meaning of
device’s response sent from the device
4/29/2024 25

26. Semantic Interoperability for Device
Interaction
• Some popular approaches
– Ontology Device ontology
– Physical domain ontology
– Estimation ontology
• Ontology-based solution is limited to the defined
domain /context
4/29/2024 26

27. Semantic Interoperability for Device
Interaction
• Collaborative conceptualization theory Object is defined based on the collaborative
concept, which is called cosign
• The representation of a collaborative sign is defined as follows:
• cosign of a object = (A, B, C, D ), where A is a cosign internal identifier, B is a
natural language, C is the context of A, and D is a definition of the object
• As an example of CCTV, cosign = (1234, English, CCTV, “Camera Type: Bullet,
Communication: Network/IP, Horizontal Resolution: 2048 TVL”)
• This solution approach is applicable for different domains/contexts
4/29/2024 27

28. Device Interoperability
• Solution approach for device interoperability
• Universal Middleware Bridge (UMB) Solves seamless
interoperability problems caused by the heterogeneity of
several kinds of home network middleware
• UMB creates virtual maps among the physical devices of all
middleware home networks, such as HAVI, Jini, LonWorks,
and UPnP
• Creates a compatibility among these middleware home
networks
4/29/2024 28

29. • The Architecture of Universal Middleware
Bridge (UMB)
– UMB consists
• UMB Core (UMB-C)
• UMB Adaptor (UMB-A)
4/29/2024 29

30. Device Interoperability (Contd.)
• UMB Core
The major role of the UMB Core is routing the
universal metadata message to the destination
or any other UMB Adaptors by the
Middleware Routing Table (MRT) .
4/29/2024 30

31. 4/29/2024 31

32. Device Interoperability (Contd.)
• UMB Adaptor UMB-A converts physical devices into
virtually abstracted one, as described by Universal Device
Template(UDT)
• UDT consists of a Global Device ID, Global Function ID,
Global Action ID, Global Event ID, and Global Parameters
• UMB Adaptors translate the local middleware’s message
into global metadata’s message
4/29/2024 32

33. 4/29/2024 33

34. 4/29/2024 34

35. 4/29/2024 35

36. Introduction to Arduino
Programming
4/29/2024 36

37. Overview
• Background
– Microcontroller defined/Why Arduino's?
– Types of Arduino microcontrollers
• What To Get (Hardware and Software)
• Arduino C
• Electronic Circuits
• Projects
– Blinking light(s)
– Reading inputs (variable resistors)
4/29/2024 37

38. Microcontrollers – One Definition
• Programmers work in the virtual world.
• Machinery works in the physical world.
• How does one connect the virtual world to the
physical world?
• Enter the microcontroller.
• A microcontroller is basically a small-scale
computer with generalized (and
programmable) inputs and outputs.
• The inputs and outputs can be manipulated by
and can manipulate the physical world.
4/29/2024 38

39. Arduino – Official Definition
• Taken from the official web site (arduino.cc):
– Arduino is an open-source electronics prototyping
platform based on flexible, easy-to-use hardware
and software. It's intended for artists, designers,
hobbyists, and anyone interested in creating
interactive objects or environments.
4/29/2024 39

40. Why Arduino?
• For whatever reason, Arduino microcontrollers
have become the de facto standard.
– Make Magazine features many projects using
Arduino microcontrollers.
• Strives for the balance between ease of use
and usefulness.
– Programming languages seen as major obstacle.
– Arduino C is a greatly simplified version of C++.
• Inexpensive ($35 retail).
4/29/2024 40

41. Arduino Types
• Many different versions
– Number of input/output channels
– Form factor
– Processor
• Leonardo
• Due
• Micro
• LilyPad
• Esplora
• Uno
4/29/2024 41

42. Leonardo
• Compared to the Uno, a slight upgrade.
• Built in USB compatibility
• Bugs?
 Presents to PC as
a mouse or
keyboard
4/29/2024 42

43. Due
• Much faster processor, many more pins
• Operates on 3.3 volts
• Similar to the Mega
4/29/2024 43

44. Micro
• When size matters: Micro, Nano, Mini
• Includes all functionality of the Leonardo
• Easily usable on a breadboard
4/29/2024 44

45. LilyPad
• LilyPad is popular for clothing-based projects.
4/29/2024 45

46. Esplora
• Game controller
• Includes joystick, four buttons, linear
potentiometer (slider), microphone, light
sensor, temperature sensor, three-axis
accelerometer.
• Not the standard set of IO pins.
4/29/2024 46

47. Arduino Uno Close Up
• The pins are in three groups:
– Invented in 2010
– 14 digital pins
– 6 analog pins
– power
4/29/2024 48

48. Where to Start
• Get an Arduino (starter kit)
• Download the compiler
• Connect the controller
• Configure the compiler
• Connect the circuit
• Write the program
• Get frustrated/Debug/Get it to work
• Get excited and immediately start next project
(sleep is for wimps)
4/29/2024 49

49. Arduino Starter Kits
• Start with a combo pack (starter kit)
– Includes a microcontroller, wire, LED's, sensors, etc.
• www.adafruit.com
adafruit.com/products/68 ($65)
• www.sparkfun.com
https://www.sparkfun.com/products/11576 ($99.95)
• Radio Shack
Make Ultimate Microcontroller Pack w/ Arduino Kit ($119.99)
• www.makershed.com
http://www.makershed.com/Ultimate_Arduino_Microcontroller_Pack_p/msump
1.htm ($150)
4/29/2024 50

50. What to Get – My Recommendation
• Required:
– Arduino (such as Uno)
– USB A-B (printer) cable
– Breadboard
– Hookup wire
– LED's
– Resistors
– Sensors
– Switches
• Good Idea:
– Capacitors
– Transistors
– DC motor/servo
– Relay
 Advanced:
 Soldering iron & solder
 Heat shrink tubing
 9V battery adapter
 Bench power supply
4/29/2024 51

51. Arduino Compiler
• Download current compiler from:
arduino.cc/en/Main/software
• Arrogantly refers to itself as an IDE (Ha!).
• Run the software installer.
• Written in Java, it is fairly slow.
Visit playground.arduino.cc/Main/
DevelopmentTools for alternatives to the
base arduino IDE
4/29/2024 52

52. Configuring the Arduino Compiler
• Defaults to COM1, will probably need to
change the COM port setting.
• Appears in Device Manager (Win7) under
Ports as a Comm port.
4/29/2024 53

53. Arduino Program Development
• Based on C++ without 80% of the instructions.
• A handful of new commands.
• Programs are called 'sketches'.
• Sketches need two functions:
– void setup( )
– void loop( )
• setup( ) runs first and once.
• loop( ) runs over and over, until power is lost or a
new sketch is loaded.
4/29/2024 54

54. Arduino C
• Arduino sketches are centered around the
pins on an Arduino board.
• Arduino sketches always loop.
– void loop( ) {} is equivalent to while(1) { }
• The pins can be thought of as global variables.
4/29/2024 55

55. Arduino C Specific Functions
• pinMode(pin, mode)
Designates the specified pin for input or output
• digitalWrite(pin, value)
Sends a voltage level to the designated pin
• digitalRead(pin)
Reads the current voltage level from the designated pin
• analog versions of above
– analogRead's range is 0 to 1023
• serial commands
– print, println, write
4/29/2024 56

56. Compiler Features
• Numerous sample
sketches are included in
the compiler
• Located under File,
Examples
• Once a sketch is
written, it is uploaded
by clicking on File,
Upload, or by pressing
<Ctrl> U
4/29/2024 57

57. Arduino C is Derived from C++
• avr-libc
#include <avr/io.h>
#include <util/delay.h>
int main(void) {
while (1) {
PORTB = 0x20;
_delay_ms(1000);
PORTB = 0x00;
_delay_ms(1000);
}
return 1;
}
• Arduino C
void setup( ) {
pinMode(13, OUTPUT);
}
void loop( ) {
digitalWrite(13, HIGH);
delay(1000);
digitalWrite(13, LOW);
delay(1000);
}
 These programs blink an LED on pin 13
4/29/2024 58

58. Basic Electric Circuit
• Every circuit (electric or electronic) must have
at least a power source and a load.
• The simplest circuit is a light.
• Plug in the light, and it lights up.
• Unplug it, the light goes out.
• Electricity flows from the power source,
through the load (the light) and then back to
the power source.
4/29/2024 59

59. Basic LED Circuit
• Connect the positive (+) lead of a power
source to the long leg of an LED.
• Connect other leg of the LED to a resistor.
– High resistance means a darker light.
– Low resistance means brighter light.
– No resistance means a burned out LED.
• Connect other leg of the resistor to the
negative lead of the power source.
4/29/2024 60

60. Let the Good Times Roll!
• At this point we have:
– Purchased a starter kit, including the Arduino
– Connected and configured the Arduino
– Connected a simple LED circuit
• Let's write some code!
4/29/2024 61

61. Blink Sketch
void setup( ) {
pinMode(13, OUTPUT);
}
void loop( ) {
digitalWrite(13, HIGH);
delay(1000);
digitalWrite(13, LOW);
delay(1000);
}
Connected to
one end of the
circuit
Connected to
other end of the
circuit
4/29/2024 62

62. 4 LED Blink Sketch
void setup( ) {
pinMode(1, OUTPUT);
pinMode(3, OUTPUT);
pinMode(5, OUTPUT);
pinMode(7, OUTPUT);
}
void loop( ) {
digitalWrite(1, HIGH);
delay (200);
digitalWrite(1, LOW);
digitalWrite(3, HIGH);
delay (200);
digitalWrite(3, LOW);
digitalWrite(5, HIGH);
delay (200);
digitalWrite(5, LOW);
digitalWrite(7, HIGH);
delay (200);
digitalWrite(7, LOW);
}
4/29/2024 63

63. So What?
• Great. Blinking lights. Not impressed.
• Only covered output thus far.
• Can use analog inputs to detect a physical
phenomena.
4/29/2024 64

64. Inputs
• Digital inputs will come to the Arduino as either
on or off (HIGH or LOW, respectively).
– HIGH is 5VDC.
– LOW is 0VDC.
• Analog inputs will come to the Arduino as a range
of numbers, based upon the electrical
characteristics of the circuit.
– 0 to 1023
– .0049 V per digit (4.9 mV)
– Read time is 100 microseconds (10,000 a second)
4/29/2024 65

65. Analog Input
• A potentiometer (variable
resistor) is connected to
analog pin 0 to an Arduino.
• Values presented to pin 0
will vary depending upon
the resistance of the
potentiometer.
4/29/2024 66

66. Analog Input-Application
• The variable resistor can be replaced with a
sensor.
• For example, a photo resistor.
– Depending upon the light level at the photo resistor:
• Turn on a light
• Increase or decrease the brightness of an LED (or an LED
array)
• Most sensors are simply variable resistors, but
vary their resistance based on some physical
characteristic.
4/29/2024 67

67. “Competitors”to the Arduino
• PIC controller
– Microcontroller programmed with C or assembler
• Alternatives to the Arduino line
– Pinguino – PIC controller
– MSP430 – Texas Instruments; $4.30
– Others: customs, Teensy, etc.
• Netduino
• Computers
– Raspberry Pi
– BeagleBones – TI; has computer and controller
4/29/2024 68

68. Introduction to Arduino Programming
4/29/2024 69

69. Content
 Operators in Arduino
 Control Statement
 Loops
 Arrays
 String
 Math Library
 Random
Number
 Interrupts
 Example
Program
4/29/2024 70

70. Operators
 Arithmetic Operators: =, +, -, *, /, %
 Comparison Operator: ==, !=, <, >, <=, >=
 Boolean Operator: &&, ||, !
 Bitwise Operator: &, |, ^, ~, <<, >>,
 Compound Operator: ++, --, +=, -=, *=, /=, %=,
|=, &=
4/29/2024 71

71. Control Statement
 If statement
 if(condition){
Statements if
the condition is
true ;
}
 If…Else statement
 if(condition ){
Statements if
the condition is
true;
}
else{
Statements if
the condition is
false;
}
If…….Elseif…..Else
 if (condition1){
• Statements if the
condition1 is true;
• }
• else if
(condition2){
Statements if the
condition1 is false
• and condition2 is true;
• }
• else{
•Statements if both
the conditions are
false;
• }
4/29/2024 72

72. Control Statement (contd..)
 Switch Case
 Switch(choice)
{
case opt1: statement_1;
break;
Case opt2: statement_2;
break;
case opt3: statement_3;break;
.
.
.
case default: statement_default; break;
}
 Conditional Operator.
 Val=(condition)?(Statement1): (Statement2)
4/29/2024 73

73. Loops
 For loop
 for(initialization; condition; increment)
{ Statement till the condition is true;
}
 While loop
 while(condition){
Statement till the condition is true;
}
 Do… While loop
 do{
Statement till the condition is true;
}while(condition);
4/29/2024 74

74. Loops (contd..)
 Nested loop: Calling a loop inside another loop
 Infinite loop: Condition of the loop is always true, the loop will
never terminate
4/29/2024 75

75. Arrays
 Collection of elements having homogenous datatype
that are stored in adjacent memory location.
 The conventional starting index is 0.
 Declaration of array:
<Datatype>
array_name[size];
Ex: int arre[5];
4/29/2024 76

76. Arrays (contd..)
 Alternative Declaration:
int arre[]={0,1,2,3,4};
int arre[5]={0,1,2};
 Multi-dimentional array Declaration:
<Datatype> array_name[n1] [n2][n3]….;
Ex: int arre[row][col][height];
4/29/2024 77

77. String
 Array of characters with NULL as termination is termed as a
String.
 Declaration using Array:
 char str[]=“ABCD”;
 char str[4];
 str[0]=‘A’;
 str[1]=‘B’;
 str[2]=‘C’;
 str[3]=D;
 Declaration using String Object:
 String str=“ABC”;
4/29/2024 78

78. String (contd..)
 Functions of String Object:
 str.ToUpperCase(): change all the characters of str to upper
case
 str.replace(str1,str2): is str1 is the sub string of str then it
will be replaced by str2
 str.length(): returns the length of the string without considering
null
4/29/2024 79

79. Math Library
 To apply the math functions and mathematical constants, “MATH.h”
header files is needed to be included.
 Functions:
 cos(double radian);
 sin(double radian);
 tan(double radian);
 fabs(double val);
 fmod(double val1, double val2);
4/29/2024 80

80. Math Library (contd..)
 Functions:
 exp(double val);
 log(double val);
 log10(double val);
 square(double val);
 pow(double base, double
power);
4/29/2024 81

81. Random Number
 randomSeed(int v): reset the pseudo-random number
generator with seed value v
 random(maxi)=gives a random number within the range
[0,maxi]
 r
n
a
i
,
n
m
d
a
o
x
m
i(mini )=gives a random number within the
range [mini,maxi]
4/29/2024 82

82. Interrupts
 An external signal for which system blocks the current
running process to process that signal
 Types:
 Hardware interrupt
 Software interrupt
 digitalPinToInterrupt(pin): Change actual digital pin to the
specific interrupt number.
 attachInterrupt(digitalPinToInterrupt(pin), ISR, mode);
 ISR: a interrupt service routine
have to be defined
4/29/2024 83

83. Example: TrafficControlSystem
Requirement:
 ArduinoBoard
 3 different color
LEDs
 330 Ohm resistors
 Jumper wires
4/29/2024 84

84. Example: Traffic Control System (contd..)
Connection:
 Connect the positive
terminals of the LEDs
to the respective
digital output pins in
the board, assigned in
the code.
 Connect the negative
terminals of the LEDs
to the ground
4/29/2024 85

85. Example: Traffic Control System
(contd..)
 Sketch
//LED pins
int r =2;
int g = 3;
int y =4;
void setup()
{
Serial.begin(9600);
pinMode(r, OUTPUT);
digitalWrite(r,LOW);
pinMode(g, OUTPUT);
digitalWrite(g,LOW);
pinMode(y , OUTPUT);
digitalWrite(y, LOW);
}
4/29/2024 86

86. Example: Traffic Control System
(contd..)
void traffic()
{
digitalWrite(g, HIGH);
Serial.println(“Green LED: ON, GO”);
delay(5000);
digitalWrite(g, LOW);
digitalWrite(y, HIGH);
Serial.println(“Green LED: OFF ; Yellow LED: ON, WAIT”);
delay(5000);
4/29/2024 87

87. digitalWrite(y,LOW);
digitalWrite(r, HIGH);
Serial.println(“Yellow LED: OFF ; Red LED: ON, STOP");
//
delay(5000);
digitalWrite(r, LOW);
Serial.println(“All OFF");
}
void loop()
{
traffic ();
delay (10000);
}
4/29/2024 88

88. Example: Traffic Control
System (contd..)
Output:
 Initially, all the LEDs are turned off
 The LEDs are turned on one at a
time with a delay of 5 seconds
 The message is displayed
accordingly
 Figure showing all the LEDs
turned on
4/29/2024 89

89. Output
4/29/2024 90

90. /
Integration of Sensors and Actuators
4/29/2024 91

91. Sensors
 Electronic elements
 Converts physical quantity/ measurements into
electrical signals
 Can be analog or digital
4/29/2024 92

92. Types of Sensors
Some commonly used
sensors:
 Temperature
 Humidity
 Compass
 Light
 Sound
 Accelerometer
4/29/2024 93

93. SensorInterface with Arduino
 Digital Humidity and
Temperature Sensor (DHT)
 PIN 1, 2, 3, 4 (from left to right)
 PIN 1- 3.3V-5V Power supply
 PIN 2- Data
 PIN 3- Null
 PIN 4- Ground
4/29/2024 94

94. DHTSensorLibrary
 A
u
p
r
d
p
u
o
i
r
n
t
o
sa
sspecial library for the DHT11 and
DHT22 sensors
 Provides function to read the temperature and
humidity values from the data pin
dht.readHumidity()
dht.readTemperatue()
4/29/2024 95

95. Connection
 Connect pin 1 of the
DHT to the 3.3 V
supply pin in the
board
 Data pin (pin 2) can
be connected to any
digital pin, here 12
 Connect pin 4 to the
ground (GND) pin of
the board
4/29/2024 96

96. Sketch: DHT_SENSOR
Install the DHT Sensor Library
 Go to Sketch -> Include
Library -> Manage Library
4/29/2024 97

97. Sketch: DHT_SENSOR (contd..)
 Search for DHT
SENSOR
 Select the “DHT
sensor library” and
install it
4/29/2024 98

98. Sketch: DHT_SENSOR (contd..)
//Initialize DHT
sensor
//Stores humidity
value
//Stores temperature
#include <DHT.h>;
DHT dht(8, DHT22);
float humidity;
float temperature; value
void setup()
{
Serial.begin(9600);
dht.begin();
}
void loop()
{
//Read data from the sensor and store it to
variables humidity and temperature
humidity = dht.readHumidity();
temperature=
dht.readTemperature();
//Print temperature and humidity values to
serial monitor
Serial.print("Humidity: ");
Serial.print(humidity);
Serial.print("%, Temperature:
"); Serial.print(temperature);
Serial.println(" Celsius");
delay(2000); //Delay of 2
seconds
}
4/29/2024 99

99. Sketch: DHT_SENSOR (contd..)
4/29/2024 100

100. Sketch: DHT_SENSOR (contd..)
 Connect the board to the
PC
 Set the port and board
type
 Verify and upload the
code
4/29/2024 101

101. Output
The readings are printed at a
delay of 2 seconds as specified
by the delay() function
4/29/2024 102

102. Actuators
 Mechanical/Electro-mechanical device
 Converts energy into motion
 Mainly used to provide controlled motion to
other components
4/29/2024 103

103. Basic Working Principle
Uses different combination of various mechanical
structures like screws, ball bearings, gears to
produce motion.
4/29/2024 104

104. Types of Motor Actuators
 Servo motor
 Stepper motor
 Hydraulic
motor
 Solenoid
 Relay
 AC motor
4/29/2024 105

105. Servo Motor
 High precision motor
 Provides rotary motion
0 to 180 degree
 3 wires in the Servo
motor
 Black is Ground
 Red is for power
supply
 Yellow for signal pin
4/29/2024 106

106. Servo Library on Arduino
A
rudinohas library to operate the servo motor-SERVO
 Create an instance of servo to use it in
the sketch
Servo myservo;
4/29/2024 107

107. Sketch: SERVO_ACTUATOR
• #include <Servo.h>
• //Including the servo library for the program
• int servoPin = 12;
• Servo ServoDemo; // Creating a
servo object
• void setup() {
• // The servo pin must be attached to the servo
before it can be used
• ServoDemo.attach(servo
Pin);
• }
void loop(){
//Servo moves to 0 degrees
ServoDemo.write(0);
delay(1000);
// Servo moves to 90 degrees
ServoDemo.write(90);
delay(1000);
// Servo moves to 180 degrees
ServoDemo.write(180);
delay(1000);
}
4/29/2024 108

108. Sketch: SERVO_ACTUATOR(contd..)
 Create an instance of Servo
 The instance must be
attached to the pin before
being used in the code
 Write() function takes the
degree value and rotates
the motor accordingly
4/29/2024 109

109. Connection
 Connect the Ground of
the servo to the ground
of the Arduino board.
 Connect the power supply
wire to the 5V pin of the
board.
 Connect the signal wire to
any digital output pin (we
have used pin 8).
4/29/2024 110

110. Board Setup
 Connect the board to the
PC
 Set the port and board
type
 Verify and upload the
code
4/29/2024 111

111. Output
The motor turns 0, 90 and
180 degrees with a delay of 1
second each.
4/29/2024 112

112. Do more with the Servo library
• Some other functions available with the Servo
library:
 Knob()
 Sweep()
 write()
 writeMicroseconds()
 read()
 attached()
 detach()
4/29/2024 113

113. Thank you!
4/29/2024 114