Subject Code: SBSBS213

Subject Name: Internet of Things

Department: MCA

Unit 2
Application Sensors & Actuators - Edge Networking (WSN) – Gateways - IoT
Communication Model – WPAN & LPWA, IoT platform for available applications,
Hardware Devices: Arduino, Raspberry pi and Smartwifi, etc, Wearable
Development Boards.
1. Application Sensors & Actuators:
1. SENSORS AND ACTUATORS
A transducer is any physical device that converts one form of energy into
another. So, in the case of a sensor, the transducer converts some physical
phenomenon into an electrical impulse that can then be interpreted to determine
a reading. A microphone is a sensor that takes vibration energy (sound waves),
and converts it to electrical energy in a useful way for other components in the
system to correlate back to the original sound.
Another type of transducer that we will encounter in many IoT systems is an
actuator. In simple terms, an actuator operates in the reverse direction of a
sensor. It takes an electrical input and turns it into physical action. For instance, an
electric motor, a hydraulic system, and a pneumatic system are all different types
of actuators.
Examples of actuators
 Digital micromirror device
 Electric motor
 Electroactive polymer
 Hydraulic cylinder
 Piezoelectric actuator
 Pneumatic actuator
 Screw jack
 Servomechanism
 Solenoid
 Stepper motor
In typical IoT systems, a sensor may collect information and route to a
control center where a decision is made and a corresponding command is
sent back to an actuator in response to that sensed input. There are many
different types of sensors. Flow sensors, temperature sensors, voltage
sensors, humidity sensors, and the list goes on. In addition, there are
multiple ways to measure the same thing. For instance, airflow might be
measured by using a small propeller like the one you would see on a
weather station. Alternatively, as in a vehicle measuring the air through
the engine, airflow is measured by heating a small element and measuring
the rate at which the element is cooling.
We live in a World of Sensors. You can find different types of Sensors in our
homes, offices, cars etc. working to make our lives easier by turning on the
lights by detecting our presence, adjusting the room temperature, detect
smoke or fire, make us delicious coffee, open garage doors as soon as our
car is near the door and many other tasks.
The example we are talking about here is the Autopilot System in aircrafts.
Almost all civilian and military aircrafts have the feature of Automatic Flight
Control system or sometimes called as Autopilot. An Automatic Flight
Control System consists of several sensors for various tasks like speed
control, height, position, doors, obstacle, fuel and many more. A Computer
takes data from all these sensors and processes them by comparing them
with pre-designed values. The computer then provides control signal to
different parts like engines, flaps, rudders etc. that help in a smooth flight.
All the parameters i.e. the Sensors (which give inputs to the Computers),
the Computers (the brains of the system) and the mechanics (the outputs of
the system like engines and motors) are equally important in building a
successful automated system. Sensor as an input device which provides an
output (signal) with respect to a specific physical quantity (input). Sensor
means that it is part of a bigger system which provides input to a main
control system (like a Processor or a Microcontroller).
S.No Sensor Applications Technology
1. Inertial sensors Industrial MEMS and
machinery, Gyroscope
automotive, human
activity
2. Speed Measuring Industrial machinery, Magnetic, light
Sensor automotive, human
activity
Proximity sensor Industrial Capacitive,
3. machinery, Inductive,
automotive, human Magnetic, Light,
activity Ultrasound
4. Occupancy sensor Home/office monitoring PassiveIR,
Ultrasound most
common
5. Temperature/ Home/office HVAC control, Solid state,
humid ity automotive, industrial thermocouple
Sensor
Light sensor Home/office/industrial Solid state,
6. lighting control photocell,
Photo
resistor,
photodiode
Home/office/industrial Coil (Faraday‘s law),
7. Power powermonitoring/control Hall effect
(current) Technology
Sensor
Air/fluid pressure Industrial Capacitive,
8. sensor monitoring/control, Resistive
automotive, agriculture
9. Acoustic sensor Industrial Diaphragm
monitoring/control, condenser
human interface
10. Strain sensor Industrial Resistive thin films
 monitoring/control,
civil infrastructure
In the first classification of the sensors, they are divided in to Active and Passive.
Active Sensors are those which require an external excitation signal or a power
signal. Passive ensors, on the other hand, do not require any external power signal
and directly generates output response. The other type of classification is based on
the means of detection used in the sensor. Some of the means of detection are
Electric, Biological, Chemical, Radioactive etc.
The next classification is based on conversion phenomenon i.e. the input
and the output. Some of the common conversion phenomena are Photoelectric,
Thermoelectric, Electrochemical, Electromagnetic, Thermo-optic, etc. The final
classification of the sensors are Analog and Digital Sensors. Analog Sensors
produce an analog output i.e. a continuous output signal with respect to the
quantity being measured.
Digital Sensors, in contrast to Analog Sensors, work with discrete or digital data.
The data in digital sensors, which is used for conversion and transmission, is digital
in nature.

Fig 1.Examples of Sensors

1. IR LED
It is also called as IR Transmitter. It is used to emit Infrared rays. The
range of these frequencies are greater than the microwave frequencies
(i.e. >300GHz to few hundreds of THz). The rays generated by an infrared
LED can be sensed by Photodiode explained below. The pair of IR LED and
photodiode is called IR Sensor.Fig 2. LED sensor
2. Photo Diode (Light Sensor)
It is a semiconductor device which is used to detect the light rays and
mostly used as IR Receiver. Its construction is similar to the normal PN
junction diode but the working principle differs from it. As we know a PN
junction allows small leakage currents when it is reverse biased so, this

property is used to detect the light rays. A photodiode is constructed such

that light rays should fall on the PN junction which makes the leakage
current increase based on the intensity of the light that we have applied.

photodiode can be used to sense the light rays and maintain the current
through the circuit. Check here the working of Photodiode with IR sensor.
3. Proximity Sensor
A Proximity Sensor is a non-contact type sensor that detects the presence
of an object. Proximity Sensors can be implemented using different
techniques like Optical (like Infrared or Laser), Ultrasonic, Hall Effect,
Capacitive, etc.
Fig 4.Proximity sensor
Some of the applications of Proximity Sensors are Mobile Phones, Cars
(Parking Sensors), industries (object alignment), Ground Proximity in
Aircrafts, etc. Proximity Sensor in Reverse Parking is implemented
in this Project: Reverse Parking Sensor Circuit.

4. Thermistor (Temperature Sensor)

 A thermistor can be used to detect the variation in temperature. It has
a negative temperature coefficient that means when the temperature increases

the resistance decreases. So, the thermistor‘s resistance can be varied with the
rise in temperature which causes more current flow through it. This change in
current flow can be used to determine the amount of change in temperature. An
application for thermistor is, it is used to detect the rise in temperature and
control the leakage current in a transistor circuit which helps in maintaining its
stability. Here is one simple application for Thermistor to control the DC fan
automatically.Fig 6.Thermistor
1. Potentiometer

A potentiometer is used to detect the position. It generally has various

ranges of resistors connected to different poles of the switch. A
potentiometer can be either rotary or linear type. In rotary type, a wiper is
connected to a long shaft which can be rotated. When the shaft has rotated
the position of the wiper alters such that the resultant resistance varies
causing the change in the output voltage. Thus the output can be calibrated
to detect the change its position.
Ultrasonic sensor

Ultrasonic means nothing but the range of the frequencies. Its range is
greater than audible range (>20 kHz) so even it is switched on we can‘t sense
these sound signals. Only specific speakers and receivers can sense those
ultrasonic waves. This ultrasonic sensor is used to calculate the distance between
the ultrasonic transmitter and the target and also used to measure the velocity of
the target.
Ultrasonic sensor HC-SR04 can be used to measure distance in the range
of 2cm-400cm with an accuracy of 3mm. Let‘s see how this module works. The
HCSR04 module generates a sound vibration in ultrasonic range when we make the
‗Trigger‘ pin high for about 10us which will send an 8 cycle sonic burst at the speed
of sound and after striking the object, it will be received by the Echo pin.
Depending on the time taken by sound vibration to get back, it provides the
appropriate pulse output. We can calculate the distance of the object based on the
time taken by the ultrasonic wave to return back to the sensor.

Fig 15.Utrasonic sensor

There are many applications with the ultrasonic sensor. We can make use of it
avoid obstacles for the automated cars, moving robots etc. The same principle will
be used in the RADAR for detecting the intruder missiles and airplanes. A mosquito
can sense the ultrasonic sounds. So, ultrasonic waves can be used as mosquito
repellent.
12. PIR sensor
PIR sensor stands for Passive Infrared sensor. These are used to detect the
motion of humans, animals or things. We know that infrared rays have a property
of reflection. When an infrared ray hits an object, depending upon the temperature
of the target the infrared ray properties changes, this received signal determines
the motion of the objects or the living beings. Even if the shape of the object
alters, the properties of the reflected infrared rays can differentiate the objects
precisely. Here is the complete working or PIR sensor.
 Fig 17.PIR Sensor
12. Gas sensor
In industrial applications gas sensors plays a major role in detecting the gas
leakage. If no such device is installed in such areas it ultimately leads to an
unbelievable disaster. These gas sensors are classified into various types based on
the type of gas that to be detected. Let‘s see how this sensor works. Underneath a
metal sheet there exists a sensing element which is connected to the terminals
where a current is applied to it. When the gas particles hit the sensing element, it
leads to a chemical reaction such that the resistance of the elements varies and

current through it also alters which finally can detect the gas.
Actuators in IoT
An IoT device is made up of a Physical object (“thing”) + Controller (“brain”)
+ Sensors + Actuators + Networks (Internet). An actuator is a machine component or
system that moves or controls the mechanism of the system. Sensors in the device
sense the environment, then control signals are generated for the actuators according
to the actions needed to perform.
A servo motor is an example of an actuator. They are linear or rotatory actuators,
can move to a given specified angular or linear position. We can use servo motors for
IoT applications and make the motor rotate to 90 degrees, 180 degrees, etc., as per our
need.
The following diagram shows what actuators do, the controller directs the actuator
based on the sensor data to do the work.
The control system acts upon an environment through the actuator. It requires a source
of energy and a control signal. When it receives a control signal, it converts the source
of energy to a mechanical operation. On this basis, on which form of energy it uses, it
has different types given below.
Types of Actuators :
1. Hydraulic Actuators –
A hydraulic actuator uses hydraulic power to perform a mechanical operation. They are
actuated by a cylinder or fluid motor. The mechanical motion is converted to rotary,
linear, or oscillatory motion, according to the need of the IoT device. Ex- construction
equipment uses hydraulic actuators because hydraulic actuators can generate a large
amount of force.
Advantages :
 Hydraulic actuators can produce a large magnitude of force and high speed.
 Used in welding, clamping, etc.
 Used for lowering or raising the vehicles in car transport carriers.
Disadvantages :
 Hydraulic fluid leaks can cause efficiency loss and issues of cleaning.
 It is expensive.
 It requires noise reduction equipment, heat exchangers, and high maintenance
systems.
2. Pneumatic Actuators –
A pneumatic actuator uses energy formed by vacuum or compressed air at high
pressure to convert into either linear or rotary motion. Example- Used in robotics, use
sensors that work like human fingers by using compressed air.
Advantages :
 They are a low-cost option and are used at extreme temperatures where using air is
a safer option than chemicals.
 They need low maintenance, are durable, and have a long operational life.
 It is very quick in starting and stopping the motion.
Disadvantages :
 Loss of pressure can make it less efficient.
 The air compressor should be running continuously.
 Air can be polluted, and it needs maintenance.
3. Electrical Actuators –
An electric actuator uses electrical energy, is usually actuated by a motor that converts
electrical energy into mechanical torque. An example of an electric actuator is a
solenoid based electric bell.
Advantages :
 It has many applications in various industries as it can automate industrial valves.
 It produces less noise and is safe to use since there are no fluid leakages.
 It can be re-programmed and it provides the highest control precision positioning.
Disadvantages :
 It is expensive.
 It depends a lot on environmental conditions.
Other actuators are –
 Thermal/Magnetic Actuators –These are actuated by thermal or mechanical
energy. Shape Memory Alloys (SMAs) or Magnetic Shape‐Memory Alloys (MSMAs) are
used by these actuators. An example of a thermal/magnetic actuator can be a piezo
motor using SMA.
 Mechanical Actuators – A mechanical actuator executes movement by converting
rotary motion into linear motion. It involves pulleys, chains, gears, rails, and other
devices to operate. Example – A crankshaft.
 Soft Actuators
 Shape Memory Polymers
 Light Activated Polymers
 With the expanding world of IoT, sensors and actuators will find more usage in
commercial and domestic applications along with the pre-existing use in industry.
2. Edge Networking:
What is edge networking?
Edge networking is a cloud-based networking architecture that locates computing
resources and data storage close to where they’re needed – near end-user devices at the
‘edge’ of a network. This differs from traditional cloud computing, where data is
processed in centralised data centres.
In edge networks, devices such as sensors, routers, and IoT devices handle a significant
amount of data processing locally. This helps to reduce latency and bandwidth usage,
enabling real-time data processing for applications like AI, IoT (Internet of Things) and
5G.
For example, in 5G networks, edge networking enables ultra-low latency, high speed
communications, essential for applications like autonomous vehicles, real-time gaming
and augmented reality (AR).
How does edge networking work?
Edge networking works by processing and storing data at or close to the devices that
generate the data.
For example, autonomous vehicles like self-driving cars generate vast amounts of data
from sensors, cameras and other devices. Instead of transmitting it to a distant cloud
server, data is processed in or near the vehicle in real time, enabling split-second
decisions about steering, braking, speed and navigation.
Autonomous vehicle edge network

From cameras in self-driving cars to sensors in smart factories or your mobile phone,
edge networks rely on edge devices to compute data at the edge.
Let‘s take a factory as a typical case for an IoT system. A factory would need a
large number of connected sensors and actuators scattered over a wide area, and a
wireless technology would be the best fit.
 Fig 24.Wireless Sensor Network Architecture
A wireless sensor network (WSN) is a collection of distributed sensors that monitor
physical or environmental conditions, such as temperature, sound, and pressure.
Data from each sensor passes through the network node-to-node.
WSN Nodes
WSN nodes are low cost devices, so they can be deployed in high volume.
They also operate at low power so that they can run on battery, or even use energy
harvesting. A WSN node is an embedded system that typically performs a single
function (such as measuring temperature or pressure, or turning on a light or a
motor).
Energy harvesting is a new technology that derives energy from external
sources (for example, solar power, thermal energy, wind energy, electromagnetic
radiation, kinetic energy, and more). The energy is captured and stored for use by
small, low-power wireless autonomous devices, like the nodes on a WSN.
WSN Edge Nodes
A WSN edge node is a WSN node that includes Internet Protocol connectivity. It
acts as a gateway between the WSN and the IP network. It can also perform local
processing, provide local storage, and can have a user interface.
Fig 25.WSN Edge

Fig 25.Edge
What are edge devices?
An edge device is a device at the edge of a network that connects to another
network. Put simply, it’s a bridge between two networks.
In addition, edge devices may filter, aggregate and process data without transmitting it
to central cloud servers. Here are some common edge devices and the role they play.
Common edge devices

Device Function

Manage and direct network traffic, allowing different edge

devices to communicate. By prioritising data in real time,
Edge routers
they can decide which data needs to be forwarded to the
cloud, optimising bandwidth usage.

Connect IoT devices to the cloud. By aggregating and

Edge gateways analysing data from multiple devices, they can ‘make
decisions’ autonomously without relying on cloud servers.

Process data close to the data source. They may be

Edge servers standalone or integrated into other edge devices, like
routers, gateways or IoT sensors.

Collect and process real-time data about physical

conditions, allowing devices to respond remotely. For
IoT sensors example, sensors measuring temperature, humidity, or
air quality in industrial or agricultural settings can trigger
actions like adjusting heating or water levels.

Record and process video on the spot. Using AI, smart

Smart cameras security cameras can analyse footage locally and trigger
an alarm if they detect suspicious activity.

Industrial Collect and analyse production line data in real time. This
controllers allows them to optimise efficiency and reduce downtime.

Mobile devices Collect and process user data autonomously. With

increasingly large storage, memory and processing
power, smartphones, tablets and laptops now support AI
 and AR/VR.

Edge networking benefits

Edge networks offer several key benefits, especially for applications where fast, local
data processing is critical. Here are some of the main advantages:
 Reduced latency: By reducing the amount of data sent to central cloud servers,
edge networking can significantly reduce latency and boost network response
times.
 Optimised bandwidth: With less data sent to the cloud, edge networks generally
use less bandwidth, reducing costs and improving overall efficiency.
 Real-time insights: As edge devices process data locally in real time, they enable
time-critical applications like autonomous vehicles, smart manufacturing and
health care monitoring.
 Enhanced data security: With local data processing, less sensitive data is sent
over the internet, reducing the risk of interception. However, decentralised edge
devices with limited security resources provide more entry points for hackers, so
they must be adequately secured against attack.
As data consumption explodes, the fast processing, low latency and increased efficiency
of edge networks make them ideal for various applications.
Edge networking use cases
Edge networks increasingly play a critical role in data-intensive emerging technologies.
Here are some common uses.
Industrial IoT
In Industrial Internet of Things (IIoT) applications, edge networking enables multiple
devices to make decisions on the spot. For example, in smart cities, cameras and
sensors control street lighting, operate traffic lights and monitor pollution levels.
5G networks
Telecom providers use edge networking in 5G mobile networks. By processing data at
the edge, 5G networks deliver the high-speed data transfer essential for emerging
mobile tech like self-driving cars and AR headsets.
Autonomous vehicles
Equipped with cameras, radar, and laser-based sensors (LiDAR) , self-driving cars rely on
edge networks. By processing driving data in or near the vehicle, they can constantly
observe the road and surroundings, making split-second decisions to manage the car.
AR and VR
Augmented reality (AR) and virtual reality (VR) rely on ultra low latency to deliver real-
time experiences without delay. Managing data on the edge in end-user devices allows
AR/VR applications to create a realistic, immersive experience.
Healthcare
In healthcare facilities, medical devices process data on the premises to enable real-time
patient monitoring and fast diagnosis. Remotely, wearable devices analyse data to
detect unusual patterns in a patient’s vital signs and alert healthcare providers.
Energy management
In the UK’s emerging smart grid, energy network operators use edge networking to
monitor and control energy sources. By controlling local distributed energy sources in
real time, the smart grid can balance supply and demand dynamically.
Content delivery networks
Edge networks are critical for content delivery networks (CDN), which store data locally
to speed up delivery to end users. For example, a streaming service may cache video
near end users to minimise buffering and enhance customer experience.
Security and remote monitoring
Edge networking enables security cameras and other local sensors to provide real-time
monitoring. By analysing video footage and sensor data at the edge rather than sending
it to centralised servers, they can send alerts instantly.
The challenges of edge networking
Despite the many advantages of edge networks, deploying and maintaining them can be
challenging. Here are some key issues to consider.
Network complexity
Since edge networks often comprise numerous fixed or mobile edge devices with
different standards, protocols or software, deploying and managing them can be
complex. In addition, current automation tools for remotely orchestrating,
troubleshooting and maintaining equipment may not work in new edge deployments.
Network reliability
Edge networks may be deployed in areas with poor connectivity. Maintaining reliable
ultra low latency connections between central servers and the edge can be difficult,
especially with mobile devices.
Data management
Edge devices generate a massive volume of data, so deciding what to process locally
and what to send to the cloud is critical. As edge devices typically have limited
processing and storage capacity, businesses often abandon valuable data because they
lack the resources to process it.
Scalability challenges
Some edge networks are simple to scale up. Instead of upgrading costly central servers,
you can simply add or upgrade edge devices. However, edge device capacity is limited,
and many current purpose-built edge deployments can’t always adapt to meet evolving
business needs.
Security and privacy
As mentioned above, edge deployments can enhance data security by reducing the
amount of sensitive data sent over the internet to central servers. However, numerous
multiple edge devices increase the ‘attack surface’ for hackers and must be secured with
robust security policies and user access controls.
To sum up, edge networks are complex to design and implement. In the future,
deployments should become simpler as unified edge platforms and open standards
emerge.
The future of edge networking
As the demand for real-time data processing grows, edge networking is set to become a
core component of our digital lives. Here are six emerging trends shaping its future.
1. IoT, 5G and 6G
With the rollout of 5G (and 6G on the horizon), the number of IoT devices worldwide is
set to double by 2030, reaching around 40 billion. Edge networking will be vital to
manage the vast amounts of data generated. Meanwhile, the global edge data centre
market is expected to grow at a CAGR of almost 15%, rising to $33.9bn by 2030.
2. Security and privacy
More advanced security measures, like zero-trust architectures, will be developed to
ensure data security and privacy in edge devices. Zero-trust security means that no
device on the network is trusted by default and requires continuous authentication to
gain access.
3. AI and ML
As artificial intelligence and machine learning develop, edge devices will be able to
perform increasingly complex analyses in real time. For example, edge networks can
enable federated learning (FL), where ML models are trained locally on edge devices,
keeping data private from central cloud servers.
4. Edge standardisation
A critical question that needs resolving is common standards for edge networking. The
continued evolution and adoption of open standards, such as ETSI Multi-access Edge
Computing, KubeEdge, and EdgeX Foundry, will be vital to ensure interoperability
between vendors. Similarly, we can expect unified edge platforms to emerge with
common frameworks for deploying and maintaining edge networks.
5. Hybrid architectures
As edge networks evolve, they will increasingly integrate with cloud infrastructure.
As Neos Networks CTOO Matt Rees observes, “A hybrid approach of strategically placed
data centres at the edge of the network, in combination with central data centres, will be
essential to manage the rapid information flow cost-effectively and sustainably.” At the
same time, more cloud providers will offer edge networking as a service (Edge-as-a-
Service or EaaS).
6. Sustainability
Cloud computing is highly power-hungry, as shown by Google’s massive 48% jump in
greenhouse gas emissions in recent years. In the UK, data centre power consumption
is forecast to rise six-fold over the next ten years. Optimising smaller, more efficient
edge data centres that use green energy and cooling solutions will be vital for a more
sustainable future.
In short, edge networking is set to play a central role in our digital future, touching all
aspects of our lives. Get ready to move to the edge.
Internet of Things (IoT) Gateways
Gateway provides a bridge between different communication technologies which
means we can say that a Gateway acts as a medium to open up connections between
the cloud and controller(sensors/devices) in Internet of Things (IoT) . With the help of
gateways, it is possible to establish device-to-device or device-to-cloud communication.
A gateway can be a typical hardware device or software program. It enables a
connection between the sensor network and the Internet along with enabling IoT
communication, it also performs many other tasks such as this IoT gateway performs
protocol translation, aggregating all data, local processing, and filtering of data before
sending it to the cloud, locally storing data and autonomously controlling devices based
on some inputted data, providing additional device security. The below figure shows
how IoT Gateways establish communication between sensors and the cloud (Data

System):
As IoT devices work with low power consumption(Battery power) in other words they
are energy constrained so if they will directly communicate to cloud/internet it won’t be
effective in terms of power. So they communicate with Gateway first using short range
wireless transmission modes/network like ZigBee, Bluetooth, etc as they consume less
power or they can also be connected using long range like Cellular and WiFi etc.
Then Gateway links them to Internet/ cloud by converting data into a standard
protocol like MQTT. using ethernet, WiFi/cellular or satellite connection. And in mostly
Gateway is Mains powered unlike sensor nodes which are battery powered. In practice
there are multiple Gateway devices. Let’s think about a simple IoT gateway, then our
smartphone comes into picture as it can also work as a basic IoT gateway when we use
multiple radio technologies like WiFi, Bluetooth, Cellular network of smart phone to
work on any IoT project in sending and receiving data at that time this also acts as a
basic IoT Gateway.
Key functionalities of IoT Gateway :
 Establishing communication bridge
 Provides additional security.
 Performs data aggregation.
 Pre processing and filtering of data.
 Provides local storage as a cache/ buffer.
 Data computing at edge level.
 Ability to manage entire device.
 Device diagnostics.
 Adding more functional capability.
 Verifying protocols.
Working of IoT Gateway :
1. Receives data from sensor network.
2. Performs Pre processing, filtering and cleaning on unfiltered data.
3. Transports into standard protocols for communication.
4. Sends data to cloud.
IoT Gateways are key element of IoT infrastructure as Gateways establish connection
for communication and also performs other task as described above. So IoT Gateway is
one of most essential thing when we start think about an IoT ecosystem.
Advantages of Gateway:
There are several advantages of using a gateway in the Internet of Things (IoT),
including:
 Protocol translation: IoT devices typically use different communication protocols,
and a gateway can translate between these protocols to enable communication
between different types of devices.
 Data aggregation: A gateway can collect data from multiple IoT devices and
aggregate it into a single stream for easier analysis and management.
 Edge computing: Gateways can perform edge computing tasks such as data
processing, analytics, and machine learning, enabling faster and more efficient
decision-making.
 Security: Gateways can act as a secure access point for IoT devices, providing a
layer of protection against cyber threats.
 Scalability: Gateways can support a large number of IoT devices and can be easily
scaled up or down to meet changing needs.
 Improved reliability: Gateways can help to improve the reliability of IoT devices
by managing network connectivity and providing a backup mechanism in case of
network failure.
 Cost-effective: Gateways can be a cost-effective way to manage and control a
large number of IoT devices, reducing the need for expensive infrastructure and IT
resources.
5. IoT Communication Model:
 IoT devices are found everywhere and will enable circulatory intelligence in the
future. For operational perception, it is important and useful to understand how various
IoT devices communicate with each other. Communication models used in IoT have
great value. The IoTs allow people and things to be connected any time, any space,
with anything and anyone, using any network and any service.
Types of Communication Model :
1.Request & Response Model –
This model follows a client-server architecture.
 The client, when required, requests the information from the server. This request is
usually in the encoded format.
 This model is stateless since the data between the requests is not retained and each
request is independently handled.
 The server Categories the request, and fetches the data from the database and its
resource representation. This data is converted to response and is transferred in an
encoded format to the client. The client, in turn, receives the response.
 On the other hand — In Request-Response communication model client sends a
request to the server and the server responds to the request. When the server
receives the request it decides how to respond, fetches the data retrieves resources,
and prepares the response, and sends it to the client.

2. Publisher-Subscriber Model –
This model comprises three entities: Publishers, Brokers, and Consumers.
 Publishers are the source of data. It sends the data to the topic which are managed
by the broker. They are not aware of consumers.
 Consumers subscribe to the topics which are managed by the broker.
 Hence, Brokers responsibility is to accept data from publishers and send it to the
appropriate consumers. The broker only has the information regarding the consumer
to which a particular topic belongs to which the publisher is unaware of.

3. Push-Pull Model – The push-pull model constitutes data publishers, data

consumers, and data queues.
 Publishers and Consumers are not aware of each other.
 Publishers publish the message/data and push it into the queue. The consumers,
present on the other side, pull the data out of the queue. Thus, the queue acts as
the buffer for the message when the difference occurs in the rate of push or pull of
data on the side of a publisher and consumer.
 Queues help in decoupling the messaging between the producer and consumer.
Queues also act as a buffer which helps in situations where there is a mismatch
between the rate at which the producers push the data and consumers pull the data.

4. Exclusive Pair –
 Exclusive Pair is the bi-directional model, including full-duplex communication
among client and server. The connection is constant and remains open till the client
sends a request to close the connection.
 The Server has the record of all the connections which has been opened.
 This is a state-full connection model and the server is aware of all open connections.
 WebSocket based communication API is fully based on this model.

1. Low Power Wide Area Networks: An Overview

Low Power Wide Area (LPWA) networks represent a novel communication
paradigm, which will complement traditional cellular and short range wireless
technologies in addressing diverse requirements of IoT applications. LPWA
technologies offer unique sets of features including wide- area connectivity for low
power and low data rate devices, not provided by legacy wireless technologies.
LPWA networks are unique because they make different tradeoffs than the
traditional technologies prevalent in IoT landscape such as short-range wireless
networks e.g., Zig- Bee, Bluetooth, Z-Wave, legacy wireless local area networks
(WLANs) e.g., Wi-Fi, and cellular networks e.g. Global Sys- tem for Mobile
Communications (GSM), Long-Term Evolution (LTE) etc. The legacy non-cellular
wireless technologies are not ideal to connect low power devices distributed over
large geographical areas. The range of these technologies is limited to a few
hundred meters at best.
The devices, therefore, cannot be arbitrarily deployed or moved anywhere, a
requirement for many applications for smart city, logistics and personal health
The range of these technologies is extended using a dense deployment of devices
and gateways connected using multihop mesh networking. Large deployments
are thus prohibitively expensive. Legacy WLANs, on the other hand, are
characterized by shorter coverage areas and higher power consumption for
machine- type communication (MTC).
A wide area coverage is provided by cellular networks, a reason of a wide
adoption of second generation (2G) and third generation (3G) technologies for
M2M communication. How- ever, an impending decommissioning of these
technologies[5], as announced by some mobile network operators (MNOs),will
broaden the technology gap in connecting low-power devices. In general,

traditional cellular technologies do not achieve energy efficiency high enough to

offer ten years of battery lifetime. The complexity and cost of cellular devices is
high due to their ability to deal with complex waveforms, optimized for voice,
high speed data services, and text. For low-power MTC, there is a clear need to
strip complexity to reduce cost. Efforts in this direction are underway for cellular
networks by the Third Generation Partnership Project and are covered as
Fig 30.Applications of LPWA technologies
across different sectors
Key Objective Of LPWA Technologies
A. Long range
LPWA technologies are designed for a wide area coverage and an excellent signal
propagation to hard-to-reach indoor places such as basements. The physical layer
compromises on high data rate and slows downs the modulation rate to put more
energy in each transmitted bit (or symbol). Due to this reason, the receivers can
decode severely attenuated signals correctly. Typical sensitivity of state of the art
LPWA receivers reaches as low as -130 dBm.
B. Ultra low power operation
Ulra-low power operation is a key requirement to tap into the huge business
opportunity provided by battery-powered IoT/M2M devices. A battery lifetime of
10 years or more with AA or coin cell batteries is desirable to bring the
maintenance cost down.
C. Topology
While mesh topology has been extensively used to extend the coverage of short
range wireless networks, their high deployment cost is a major disadvantage in con-
necting large number of geographically distributed devices. Further, as the traffic is
forwarded over multiple hops towards a gateway, some nodes get more congested
than others depend- ing on their location or network traffic patterns. Therefore, they
deplete their batteries quickly, limiting overall network lifetime to only a few months
to years .On the other hand, a very long range of LPWA technologies overcomes
these limitations by connecting end devices directly to base stations, obviating the
need for the dense and expensive deployments of relays and gateways altogether.
The resulting topology is a star that is used extensively in cellular networks and
brings huge energy saving advantages. As opposed to the mesh topology, the
devices need not to waste precious energy in busy-listening to other devices that
want to relay their traffic through them. An always-on base station provides
convenient and quick access when required by the end-devices.
D. Duty Cycling: Low power operation is achieved by opportunistically turning
off power hungry components of M2M/IoT devices e.g., data transceiver. Radio
duty cycling allows LPWA end devices to turn off their transceivers, when not
required. Only when the data is to be transmitted or received, the transceiver is
turned on.
E. Lightweight Medium Access Control: Most-widely used Medium Access
Control (MAC) rotocols for cellular net- works or short range wireless networks
are too complex for LPWA technologies. For example, cellular networks synchro-
nize the base stations and the user equipment (UE) accurately to benefit from
complex MAC schemes that exploit frequency.
CHALLENGES AND OPEN RESEARCH DIRECTIONS LPWA
On the business side, the proprietary solution providers are in a rush to bring their
services to the market and capture their share across multiple verticals. In this race,
it is easy but counter- productive to overlook important challenges faced by LPWA
technologies. In this section, we highlight these challenges and some research
directions to overcome them and improve performance in long-term.
Scaling networks to massive number of devices
LPWA technologies will connect tens of millions of devices transmitting data at
an unprecedented scale over limited and often shared radio resources. This
complex resource allocation problem is further complicated by several other factors.
First, the device density may vary significantly across different geographical
areas, creating the so called hot-spot problem. These hot-spots will put the LPWA
base stations to a stress test. Second, cross-technology interference can severely
de- grade the performance of LPWA technologies.
Interoperability between different LPWA technologies
Given that market is heading towards an intense competition between different
LPWA technologies, it is safe to assume that several may coexist in future.
Interoperability between these heterogeneous technologies is thus crucial to their
long- term profitability. With little to no support for interoperability between
different technologies, a need for standards that glue them together is strong.
Interoperability is a still an open challenge. Test beds and open-source tool chains
for LPWA technologies are not yet widely available to evaluate interoperability
mechanisms.
Localization
LPWA networks expect to generate significant revenue from logistics, supply
chain management, and personal IoT applications, where location of mobile
objects, vehicles, humans, and animals may be of utmost interest. An accurate
localization support is thus an important feature for keeping track of valuables,
kids, elderly, pets, shipments, vehicle fleets, etc. In fact, it is regarded as an
important feature to enable new applications.
Link optimizations and adaptability
If a LPWA technology permits, each individual link should be optimized for high
link quality and low energy consumption to maximize overall network capacity.
Every LPWA technology allows multiple link level configurations that introduce
tradeoffs between different performance metrics such as data rate, time-on-air,
area coverage, etc. This motivates a need for adaptive techniques that can
monitor link quality and then read just its parameters for better performance.
However for such techniques to work, a feedback from gateway to end devices is
usually required over down link.
LPWA test beds and tools
LPWA technologies enable several smart city applications. A few smart city test
beds e.g. Smart Santander have emerged in recent years. Such test beds
incorporate sensors equipped with different wireless technologies such as Wi-Fi,
IEEE 802.15.4 based networks and cellular networks. How- ever, there are so far
no open test beds for LPWA networks. Therefore, it is not cost-effective to widely
design LPWA systems and compare their performance at a metropolitan scale. At
the time of writing, only a handful of empirical studies compare two our more
LPWA technologies under same conditions. In our opinion, it is a significant
barrier to entry for potential customers. Providing LPW technologies as
a scientific instrumentation for general public through city governments can
act as a confidence building measure.
Authentication, Security, and Privacy
Authentication, security, and privacy are some of the most important features
of any communication system. Cellular networks provide proven authentication,
security, and privacy mechanisms. Use of Subscriber Identity Modules (SIM)
simplifies identification and authentication of the cellular devices. LPWA
technologies, due to their cost and energy considerations, not only settle for simpler
communication protocols but also depart from SIM based authentication.
Techniques and protocols are thus required to provide equivalent or better
authentication support for LPWA technologies. Further to assure that end devices
are not exposed to any security risks over prolonged duration, a support for over-
the-air (OTA) updates is a crucial feature. A lack of adequate support for OTA
updates poses a great security risk to most LPWA technologies.
Mobility and Roaming
Roaming of devices between different network operators is a vital feature
responsible for the commercial success of cellular networks. Whilst some LPWA
technologies do not have the notion of roaming (work on a global scale such as
SIGFOX), there are others that do not have support for roaming as of the time of
this writing. The major challenge is to provide roaming without compromising the
lifetime of the devices. To this effect, the roaming support should put minimal
burden on the battery powered end-devices. Because the end-devices duty cycle
aggressively, it is reasonable to assume that the low power devices cannot receive
downlink traffic at all times. Data exchanges over the uplink should be exploited
more aggressively. Network assignment is to be resolved in backend systems as
opposed to the access network. All the issues related to agility of roaming process
and efficient resource management have to bead dressed.
Wireless Personal Area Network (WPAN)
WPANs are used to convey information over short distances among a private,
intimate group of participant devices. Unlike a WLAN, a connection made through a
WPAN involves little or no infrastructure or direct connectivity to the world outside
the link. This allows small, power-efficient, inexpensive solutions to be implemented
for a wide range of device.
Applications
 Short-range (< 10 m) connectivity for multimedia applications
 PDAs, cameras, voice (hands free devices)
 High QoS, high data rate (IEEE 802.15.3)
 Industrial sensor applications
 Low speed, low battery, low cost sensor networks (IEEE 802.15.4)
 Common goals
 Getting rid of cable connections
 Little or no infrastructure
 Device interoperability
WPAN Topologies:

Fig 31 WPAN
Topologies IEEE 802.15 WPAN Standards:
1. IEEE 802.15.2- Co existence of Bluetooth and 802.11b
2. IEEE 802.15.3- High Rate WPAN
Low power and low cost applications for digital imaging and multimedia applications.
3. IEEE 802.15.4- Low Rate WPAN
Industrial ,Medical and agriculture applications.
Bluetooth ≈ IEEE 802.15.1
A widely used WPAN technology is known as Bluetooth (version 1.2 or version 2.0).
The IEEE standard specifies the architecture and operation of Bluetooth devices, but
only as far as physical layer and medium access control (MAC) layer operation is
concerned (the core system architecture). Higher protocol layers and applications
defined in usage profiles are standardized by the Bluetooth SIG. Bluetooth is the base for
IEEE Std 802.15.1-2002 (rev. 2005).Data rate of 1 Mbps (2 or 3 Mbps with enhanced data
rate).
Piconets
◻ Bluetooth enabled electronic devices connect and communicate wirelessly
through short-range, ad hoc networks known as piconets. Piconets are
established dynamically and automatically as Bluetooth enabled devices enter
and leave radio proximity. Up to 8 devices in one piconet (1 master and up to 7
slave devices)
◻ Max range is 10 m. The piconet master is a device in a piconet whose clock
and device address are used to define the piconet physical channel
characteristics. All other devices in the piconet are called piconet slaves.All
devices have the same timing and frequency hopping sequence. At any given
time, data can be transferred between the master and one slave.
◻ The master switches rapidly from slave to slave in a round-robin fashion. Any
Bluetooth device can be either a master or a slave. Any device may switch the
master/slave role at any time.
Scatternet
Any Bluetooth device can be a master of one piconet and a slave of another piconet
at the same time (scatternet). Scatternet is formed by two ormore Piconets. Master
of one piconet can participate as a slave in another connected piconet. No time or
frequency synchronization between piconets
Bluetooth Protocol Stack Radio Layer
The radio layer specifies details of the air interface, including the usage of the
frequency hopping sequence, modulation scheme, and transmit power. The radio
layer FHSS operation and radio parameters
Baseband Layer
The baseband layer specifies the lower level operations at the bit and packet
levels. It supports Forward Error Correction (FEC) operations and Encryption,
Cyclic Redundancy Check (CRC) calculations. Retransmissions using the
Automatic Repeat Request (ARQ) Protocol.
 Fig 32 Bluetooth Protocol Stack
Link Manager layer
The link manager layer specifies the establishment and release links, authentication,
traffic scheduling, link supervision, and power management tasks. Responsible for all
the physical link resources in the system. Handles the control and negotiation of
packet sizes used when transmitting data.Sets up, terminates, and manages
baseband connections between devices. L2CAP layer
The Logical Link Control and Adaptation Protocol (L2CAP) layer handles the
multiplexing of higher layer protocols and the segmentation and reassembly (SAR) of
large packets The L2CAP layer provides both connectionless and connection-oriented
services
L2CAP performs 4 major functions
Managing the creation and termination of logical links for each connection through
channel structures. Adapting Data, for each connection, between application
(APIs) and Bluetooth Baseband formats through Segmentation and Reassembly
(SAR). Performing Multiplexing to support multiple concurrent connections over a
single common radio interface (multiple apps. using link between two devices
simultaneously). L2CAP segments large packets into smaller baseband
manageable packets. Smaller received baseband packets are reassembled coming
back up the protocol stack.
RFCOMM
Applications may access L2CAP through different support protocols Service Discovery
Protocol (SDP) RFCOMM Telephony Control Protocol Specification (TCS) TCP/IP based
applications, for instance information transfer using the Wireless Application Protocol
(WAP), can be extended to Bluetooth devices by using the Point-to-Point Protocol (PPP)
on top of RFCOMM.
OBEX Protocol
The Object Exchange Protocol (OBEX) is a sessionlevel protocol for the exchange of
objects This protocol can be used for example for phonebook, calendar or
messaging synchronization, or for file transfer between connected devices.
TCSBIN Protocol
The telephony control specification - binary (TCS BIN) protocol defines the call-
control signaling for the establishment of speech and data calls between
Bluetooth devices In addition, it defines mobility management procedures for
handling groups of Bluetooth devices.
Service Discovery Protocol
The Service Discovery Protocol (SDP) can be used to access a specific device (such
as a digital camera) and retrieve its capabilities, or to access a specific application
(such as a print job) and find devices that support this application.
2. Smart Wi-Fi module
Smart Wi-Fi is an IoT-enabler tool. The applications it can cater to are only
limited by the imagination of makers. The very basic applications could be for
smart homes or smart offices. This module can be used for data logging, data
monitoring and more, and provides very good support for product
development. It also has all features to act as a full-fledged product. Platforms
such as ThingSpeak add to the benefits and provide support for testing and
development of an IoT product. Smart Wi-Fi enables making a product quickly
and reliably. With open software resources and hardware data, moving to the
final product after the proof of concept is also easy.
IoT Platform Supported:
Internet of Things is no longer a newer concept. Undoubtedly, businesses and
industries are widely accepting the Internet of Things systems. Thus, the practice of
these high-tech IoT platforms is rapidly increasing. You should have a keen knowledge
of the IoT Development Platforms. It will help you to accomplish the Internet of Things
product expansion.
1. Google Cloud IoT Platform
The giant Techno company has used the IoT platforms for efficiency. According to
Google, the Cloud Platform is the top part for encouraging IoT technology. Moreover,
with the utmost security system, Google Cloud offers complete functioning effectively.
Standing as one of the top Internet of Things Platforms, it offers various fascinating
features. For example, robust A.I. aptitudes, Fast business procedures, Machine
learning with vast capacity. Not only these, but the Google Cloud IoT also increases the
work rate of the devices. This platform uses cloud amenities to lessen the cost and
inspires location intelligence as well. They mainly focus on effective, fast, and efficient
ways to run your business. In addition, the Google Cloud platform offers real-time
understandings of devices used worldwide. This Google platform makes files
maintenance and sharing easy. You can operate this IoT platform within any operating
system without any problems.
2. Amazon Web Services Platform for IoT
Another best Internet of Things Platform that is easily available currently. Amazon was
the first and foremost company that uses the cloud as an IoT platform in the year 2004.
Since that time, Amazon has put a lot of energy into building Amazon web services as
the best IoT platform. This platform offers the most innovative and captivating features
for its users. Also, they provide the most wide-ranging set of tools in the market. As it is
easy and has a uniqueness in its properties, several companies use it throughout the
world. Moreover, because of IoT device management, you can easily connect and
extend your devices. Amazon authorities have examined its versatility and adaptability
properly. Therefore, they assure that this platform is safe and secure for the users.
3. 2Smart Cloud
This IoT device development platform is known as a product suitable for any audience
passionate about the Internet of Things, with many unique features and flexible pricing.
Enthusiasts utilize here low-code device programming using ESPHome’s simple syntax
and enjoy the free connection of up to 20 devices.
Startups are attracted to the platform because it provides a ready-made mobile
application, which is configured using a no-code builder with an extensive library of
ready-made widgets.
Enterprises use the 2Smart Business Platform to manage their fleets of IoT devices with
the ability to brand the platform and mobile app using a white-label model. The
Business Platform provides flexible tools for managing companies and users, restricting
access levels for administrators, as well as advanced device monitoring and
maintenance.
The 2Smart team keeps up with trends and offers the best user experience to end
users. A modern mobile application with a fast-reactive interface allows one to use a
wide range of control options, particularly voice commands for Siri and Google Home,
instant messengers bots, phone calls, and many IFTTT integrations. Users can also
utilize several options to share their devices with others easily.
2Smart Cloud is an excellent example of how an IT product, developed not by one of
the long-term market leaders, is ready to compete with majors and can meet the needs
of the broadest possible audience.
4. ThingWorx
The ThingWorx IoT platform is created with low development cost and taken less time
for building. In addition, this platform offers a flexible solution that allocates fine run
time, complete app design, and an intellectual environment. The ThingWorx helps the
users to overcome the challenges in their businesses and increases their overall
performances. Also, it allows you to connect effortlessly with more devices to diverse
platforms. Furthermore, it provides scalability and elasticity to the technological world.
The inclusion of a machine learning system helps the users to integrate with their
devices. Moreover, it offers real-time intuitions from the industrial Internet of things.
This enables the users to improve the business processes effectively.
5. Microsoft Azure IoT Platform
The Microsoft open-source Internet of Things platform allows you to build safe and
mountable edge-to-cloud results rapidly. As per the companies’ desires, you can use
this platform for developing your apps flexibly. It consists of the boosted Artificial
Intelligence solutions. The Microsoft Azure IoT Platform offers ready-to-use tools,
facilities, and models to develop the apps accordingly. Undoubtedly, this platform
protects the data and files from the cloud. The Azure platform completely manages the
databases safely. The best feature of this IoT development Platform is the Azure IoT
Edge. It has the ability to function the apps even if you are offline. Moreover, this IoT is
designed in such a way that different industrial sectors can easily use it. No matter, it is
a manufacturing industry or transportation one.
6. IRI Voracity
Undoubtedly, the IRI Voracity is an all-rounder data management platform that allows
IoT data control at every business process level. From data detection to data analytics,
IRI Voracity can handle every single thing smoothly and easily. Mainly, this platform
uses two engines, namely, Hadoop and IRI CoSort, that helps in processing large data.
IRI can discover, integrate, govern and transform data from several sources in various
forms. For example, Windows file, Linux, ISAM, HIVE, Unix, etc., and many others.
Moreover, IRI helps in sub-setting, drifting, imitating, and leveraging the IoT data for
playbooks, data lakes, and analytics.
7. Oracle IoT
Another notable and important Internet of Things Platform is Oracle. It is worldwide
popular because of its stimulated planning for computing clouds and handling
databases. The Oracle IoT platform connects the devices to the cloud without having
any issues. Basically, the oracle permits the creation of IoT apps. Thereafter, it helps
the devices to connect with JavaScript, Java, Android, iOS, etc. Furthermore, it
enhances operational growth and improves work productivity. As Oracle is popular for
its database handling services, it wires to produce a large amount of data. Due to the
adaptable feature that develops business apps, several businesses opt for oracle. In
addition, it offers exclusive digital individualities to devices that are connected. This
enhances the faith between the apps and the devices.
8. IBM Watson IoT
Last but not least, IBM Watson IoT offers various features related to IoT solutions. This
offers a completely accomplished cloud service for device management. Also, it
provides utmost scalability and flexibility to connected devices. The IBM Watson IoT
platform helps you to collect data from several sources like assets, buildings,
automobiles, and others things. Moreover, it possesses direct access to the newest
data in the Cloudant NoSQL DB solution. IBM has other fine features like collecting raw
data and understanding its patterns. This helps in taking out the treasured insights of
the unstructured data. Also, IBM supports the easy transfer of data workload to the
clouds. Moreover, this platform assists you to optimize the data and resources for your
profit.
Conclusion: In this digital world, everything is concerned with the internet that
generates data. We can use IoT platforms to use this data for enhancing business
growth. Also, IoT apps can benefit us in competitive purposes. Every project needs
different scalability, security, and space. You can select the best IoT development
platforms based on these parameters according to your requirements and desires!
Raspberry Pi in IOT
What is a Raspberry Pi? Raspberry pi is the name of the “credit card-sized computer
board” developed by the Raspberry pi foundation, based in the U.K. It gets plugged in a
TV or monitor and provides a fully functional computer capability. It is aimed at
imparting knowledge about computing to even younger students at the cheapest
possible price. Although it is aimed at teaching computing to kids, but can be used by
everyone willing to learn programming, the basics of computing, and building different
projects by utilizing its versatility.
Raspberry Pi is developed by Raspberry Pi Foundation in the United Kingdom. The
Raspberry Pi is a series of powerful, small single-board computers.
Raspberry Pi is launched in 2012 and there have been several iterations and variations
released since then.
Various versions of Raspberry Pi have been out till date. All versions consist of a
Broadcom system on a chip (SoC) with an integrated ARM-compatible CPU and on-chip
graphics processing unit (GPU).
The original device had a single-core Processor speed of device ranges from 700 MHz
to 1.2 GHz and a memory range from 256 MB to 1 GB RAM.
To store the operating system and program memory Secure Digital (SD) cards are
used. Raspbian OS which is a Linux operating system is recommended OS by Raspberry
Pi Foundation. Some other third party operating systems like RISC OS Pi. Diet Pi, Kali,
Linux can also be run on Raspberry Pi.
Used:
It also provides a set of general purpose input/output pins allowing you to control
electronic components for physical computing and explore the Internet of Things (IOT).
Raspberry pi Diagram :

Raspberry Pi model –
There have been many generations of raspberry Pi from Pi 1 to Pi 4.There is generally a
model A and model B. Model A is a less expensive variant and it trends to have reduce
RAM and dual cores such as USB and Ethernet.
List of Raspberry pi models and releases year:
1. pi 1 model B – 2012
2. pi 1 model A – 2013
3. pi 1 model B+ -2014
4. pi 1 model A+ – 2014
5. Pi 2 Model B – 2015
6. Pi 3 Model B- 2016
7. Pi 3 Model B+ -2018
8. Pi 3 Model A+ -2019
9. Pi 4 Model A – 2019
10. Pi Model B – 2020

11. Pi 400 – 2021

Specs of the Computer: – The computer has a quad-core ARM processor that doesn’t support
the same instruction as an X86 desktop CPU. It has 1GB of RAM, One HDMI port, four USB ports,
one Ethernet connection, Micro SD slot for storage, one combined 3.5mm audio/video port, and
a Bluetooth connection. It has got a series of input and output pins that are used for making
projects like – home security cameras, Encrypted Door lock, etc.
Versatility of Raspberry Pi: – It is indeed a versatile computer and can be utilized by
people from all age groups, it can be used for watching videos on YouTube, watching
movies, and programming in languages like Python, Scratch, and many more. As
mentioned above it has a series of I/O pins that give this board the ability to interact
with its environment and hence can be utilized to build really cool and interactive
projects.
Examples of projects: – It can be turned into a weather station by connecting some
instruments to it for check the temperature, wind speed, humidity etc… It can be
turned into a home surveillance system due to its small size; by adding some cameras
to it the security network will be ready. If you love reading books it can also become a
storage device for storing thousands of eBooks and also you can access them through
the internet by using this device.

Conclusion: Concluding the article it is convenient to assert that it is a small and

powerful computer at a dirt-cheap rate and can handle most of the task as a desktop
computer.
ESP8266
What is the ESP8266?
The ESP8266 module enables microcontrollers to connect to 2.4 GHz Wi-Fi, using IEEE
802.11 bgn. It can be used with ESP-AT firmware to provide Wi-Fi connectivity to external
host MCUs, or it can be used as a self-sufficient MCU by running an RTOS-based SDK. The
module has a full TCP/IP stack and provides the ability for data processing, reads and
controls of GPIOs.
ESP8266 Specifications
This is based on the ESP-12 module, which we discuss below.
ESP8266 Functions
ESP8266 has many applications when it comes to the IoT. Here are just some of the
functions the chip is used for:
 Networking: The module’s Wi-Fi antenna enables embedded devices to
connect to routers and transmit data
 Data Processing: Includes processing basic inputs from analog and digital
sensors for far more complex calculations with an RTOS or Non-OS SDK
 P2P Connectivity: Create direct communication between ESPs and other
devices using IoT P2P connectivity
 Web Server: Access pages written in HTML or development languages.
ESP8266 Applications
The ESP8266 modules are commonly found in the following IoT devices:
 Smart security devices, including surveillance cameras and smart locks
 Smart energy devices, including HVACs and thermostats
 Smart industrial devices, including Programmable Logic Controllers (PLCs)
 Smart medical devices, including wearable health monitors
Chip versus Modules versus Development Boards
As discussed above, the ESP8266 is just the name of the chip. There are essentially three
formats you can buy this in:
 ESP8266 Chip: This is the basic chip manufactured by Espressif, which comes
unshielded and needs to be soldered onto a module. This is unsuitable for most
users, apart from perhaps volume device manufacturers that can factor this into the
production process under the unit cost of a module.
 ESP8266 Modules: These are the surface-mountable modules that contain the chip,
which are ready to be mounted onto an MCU, produced by Espressif, Ai-Thinker and
certain other manufacturers. They are usually shielded and pre-approved by the FCC
for use. This means they’re a good option for device manufacturers looking to scale
production.
 ESP8266 Development Boards: These are the complete IoT MCU development
boards that have the modules preinstalled. They’re used for developers and
manufacturers to create prototypes during the design stage, before they start
production. Development boards are produced by several different manufacturers and
the specifications differ between models. Some core specifications to be aware of
when assessing ESP8266 IoT development board options include:
 GPIO pins
 ADC pins
 Wi-Fi antennas
 LEDs
 Shielding*
 Flash Memory
*Many international markets require shielded Wi-Fi devices, as Wi-Fi produces
considerable Radio Frequency Interference (RFI), and shielding minimizes this
interference. This should, therefore, be a key consideration for all developers and
embedded-device manufacture
 Ai-Thinker
 WeMos
 Adafruit
 Olimex
ESP8266 Modules
 Espressif Systems
The Espressif Systems esp8266 is available in the following modules:
Ai-Thinker
Current Ai-Thinker esp8266 modules are the following:

Older and discontinued models include: ESP-01, ESP-02, ESP-03, ESP-04, ESP-05, ESP-06,
ESP-7, ESP-08, ESP-09, ESP-10, ESP-11, ESP-12, ESP-12E, and ESP-13 and ESP-14.
ESP8266 Development Boards/Dev Kits
● ESP8266 Opensource Community

WeMos
Current WeMos boards are the following:

SDKs
There is now a wide range of software development kits (SDKs) available, enabling
developers to program the chip directly without using a separate MCU.
Espressif provides two official SDKs for use with ESP8266, which are:
  A FreeRTOS based SDK
 A Non-OS SDK
Aside from the Espressif options, there are plenty of commercial and open-source SDKs
on the market, including:
 ESP Arduino Core – C++ based firmware
 ESP8266 BASIC – Open-source BASIC-like environment for IoT
 ESP-Open-RTOS – FreeRTOS open-source framework for ESP8266
 ESP-Open-SDK – Open integrated SDK for ESP8266
 Espruino – Javascript SDK and firmware
 Micropython – Python for embedded devices
 Moddable SDK – Javascript SDK
 Mongoose OS – C or Javascript open-source OS
 NodeMCU – Open-source Lua based firmware, similar to Node.js
 Sming – Asynchronous C/C++ framework
 uLisp – Lisp-based framework
 ZBasic – Visual Basic 6 adapted for ESP8266
 Zerynth – Python framework for IoT
Which is the best ESP8266 Module or Development Board for IoT?
As the above comparisons show, there are many options available with ESP8266 IoT
boards and modules. To help you with your decision making, we’ve summarized some of
the most popular below.
Popular ESP8266 Modules

Ai-Thinker ESP-01
The ESP-01 is one of the biggest selling IoT Wi-Fi modules on the market. It’s widely used
in smart home and networking projects.
The default AT firmware enables it to be used in combination with an Arduino. However,
you can easily update the firmware with a USB-to-ESP-01 adaptor module.
A common complaint with this board is that the pin posts make it difficult to plug it
directly into a breadboard, but this can be easily overcome by building or buying an
adaptor module.
There are two versions available, one with 500kb of flash and the other with 1Mbit of
flash.

Ai-Thinker ESP-05
This module was developed to provide Wi-Fi connectivity for MCUs such as Raspberry Pi

and PIC and other Wi-Fi projects. It, t herefore, does not have GPIOS.
It fits into a breadboard without any problems, but there are some complaints about
being stuck with the factory set firmware unless you’re prepared to do some serious
modifications.

Ai-Thinker ESP-12
This is a more fully featured module with 11 GPIO pins, an ADC, 4Mbits of flash, and 10-
bit resolution. However, the module is not breadboard friendly, meaning you’ll need to
use an adaptor.
There are two versions available, ESP-12F, which has 20 GPIOS and ESP-12S, which has
14.
Popular ESP8266 Boards

Espressif NodeMCU module V1.0

This board has the ESP-12E module and comes with 4 Mbits of flash and features a row
of pins on each side of the breadboard. The board comes with four communication
interfaces: SPI, I2C, UART, and I2S, with 16 GPIO and one ADC. The RAM is 160KB,
divided into 64KB for instruction and 96KB for data.

Adafruit Huzzah ESP8266 Breakout

This microcontroller operates at a logic level of 3.3V and is clocked at 80MHz. It comes
programmed with the Lua Interpreter, which makes programming simple, with no boot
loading required. Alternatively, you can use the Arduino IDE to program it.
There is an onboard CP2104 USB-to-serial converter, therefore you can simply plug it
into your computer and upload your code. The board is also lightweight and small, so it’s
useful for projects with space constraints.
WeMos D1 Mini
The WeMos D1 Mini was designed to be one of the smallest possible development boards
for the ESP8266 module. It has a micro USB connection and compatibility with several
firmware options.
Arduino Board:
Arduino is an important device used in electronics engineering for creating mini-
projects or for integrating large projects. Arduino itself consists of various components
that can be programmed according to the project requirements using some assembly
languages like C/C++.
Arduino is the first choice of many professionals due to the ease with which it can be
programmed and how it allows interactive features for user experience. Arduino is
programmed to include both hardware and software components which account for its
use in different fields like designing, sensing, and testing.
Since Arduino is an open-source platform, it is used globally by users all across the
globe. Let us study what is an Arduino, what functionalities it has and how can we use
it in daily life.
What is Arduino?
The Arduino is one of the most popular and widely used Arduino boards. It's based on
the ATmega328P microcontroller and offers a good balance of features, performance,
and affordability, making it suitable for a wide range of projects, from simple to
moderately complex.
Most electronic devices involve circuit-making using hardware components. The
purpose of introducing Arduino was to make an easy-to-use device that can offer the
feature of programming along with circuit making. Therefore, Arduino is a
programmable device that is used mostly by artists, designers, engineers, hobbyists,
and anyone who wants to explore programming in electronics.
The Arduino uses its components to gather information from the surroundings and
generate a precise output accordingly. The information is gathered using some
components like sensors, and input pins, and an output is generated depending on the
programming done. This output can range from illuminating an LED to turning the
motors on.
Arduinos are great devices that can be used for creating interactive projects. They can
either be used alone to create basic projects or they can be integrated with Arduino,
Raspberry Pis, NodeMCU, or nearly anything else using some programming in their
software to create some advanced level of projects. It is good to know the
specifications of different Arduino so that you can select the right Arduino for your
project.
Arduino Hardware
Let us look at the hardware components of Arduino :
Arduino hardware

 Microcontroller: The Microcontroller controls the execution of all the programs

and codes uploaded on Arduino. The microcontroller is equipped with components
that can perform different functions.
 USB port: This port is used to establish a connection between the computer and the
Arduino board.
 USB to Serial chip: The USB to Serial port is used for adding data from the
computer to the microcontroller. This is how the code is uploaded from the computer
to the Arduino board.
 Digital pins: These pins are used for turning the LEDs on and off by using digital
logic ('0' and '1').
 Analog pins: These pins are used for taking analog input.
 5V / 3.3V pins: These pins are used for supplying power to devices.
 GND: This pin is used for setting a reference level.
Basic Operation
Most of the Arduino can perform a single task using the help of a microcontroller. These
tasks can be performed in a cycle as defined by the variables. This basic task can be
from blinking an LED to rotating a motor. This is how the loop in the setup will be
defined
 Set the sensor to read the input.
 Program the Arduino to turn on the light.
 Verify all the conditions.
Depending on all the delays introduced, the program takes around microseconds to
execute.
Circuit Basics

Consider this basic LED circuitLED Circuit Design

Consider the circuit shown above, the LED is connected to pins on the Arduino using
some resistors to limit the amount of current flowing through the LED. The reference
level is set using the ground pin.
During the high or the 'ON' state, the circuit connections will be complete, and current
will flow through the circuit components as programmed in the microcontroller. In this
state, the LED will glow. When the circuit is turned 'OFF', the pins are set to low and the
LED becomes dim due to no current flow.
Electronic Signals
Let us study the two types of signals:
Analog Signal: Analog signals are the ones that can have any value in a given range
of values. This range can vary from 0V to 5V. To take the input from the input pins, the
analog pins are used that can have a range of 0-255 with an 8-bit resolution. This is
how we can read a large input value in an Arduino board.
Digital Signal: Unlike analog signals, digital signals can only take a set of two values,
high('1') and low('0'). The advantage of these signals is that they can be used to turn
the Arduino on or off. Although they can take only two values, we can use these values
to generate a sequence known as the binary sequence which is a collection of zeroes
and ones which can be sent easily for communication.
Sensors And Actuators
Let us discuss about sensors and actuators :
Sensors
The term 'sensor' is self-explanatory and indicates a device that can sense any physical
quantity and convert it to a form that can be measured like a signal. Sensors can be
categorized into different forms depending on the type of quantity they measure. For
example, the temperature sensor is a device that measures temperature.
The most common example of a sensor is an analog sensor that can be used for
measuring a continuous range of values generally from 0-5V. Another type of sensor
are digital sensors that sense inputs and then generate an output in digital bits. Certain
libraries have been designed to read this digital sequence generated by the sensor for
measuring purposes.
This line of code is used for reading the value.
sensorValue = sensor.read();
Actuators
Contrary to sensors, actuators are used to change a physical state based on something
they sense. Actuators perform the task of using the signal to actuate something like
causing mechanical movement when an input is sensed or turning a light bulb on when
voltage is received.
Let us see how digitalWrite() and analogWrite().
digitalWrite(LED, HIGH); //turn on an LED
digitalWrite(LED, LOW); //turn off an LED
analogWrite(motor, 255); //set a motor to receive 255 bits
Arduino API
Arduino API refers to "Arduino Programming Language" which is generally written. Let
us see what the "Arduino Programming Language" consists of
 Functions: Functions are blocks of code that are assigned to perform a specific
task. This can include functions that can be created to 'read' and 'write' the data
from a pin.
 Variables: This includes Arduino datatypes and terms defined to be used later like
int, boolean, and array.
 Structure: All the components in the code form the whole structure. This can
include the sketch parts i.e. the loop(), setup(), the control statements like if, else,
while, for, and various comparators like as ==, !=, >.
The Arduino API simplifies the task of writing the code due to the additional libraries
that control the hardware part of Arduino.
Libraries
Libraries are useful for controlling the hardware and software part of Arduino without
the need to write the already written code. Libraries are contributed by different
developers and need to be imported into your module.
By including a library, you don't have to write complex code like reading a specific
sensor, controlling a motor, or adding wi-fi. By simply including the free open-source
libraries, you can access these functions.
The line of code used for adding a library:
#include <Library.h>
General Commands
Let us see a list of commands that are used in almost every project.
setup()
It is used to configure the program.
void setup() {
//Programs like including libraries
}
loop()
It includes the programs that will run when the board is in an "ON" state.
void loop() {
//main program here
}
delay()
This is used to add a pause in the function for a certain millisecond as required. The
code snippet shows the use of the delay function.
void loop() {
digitalWrite(LED, HIGH); //turn on an LED
delay(1000); //paused for 1 second(1000 milliseconds)
digitalWrite(LED, LOW); //the LED is turned off
}
millis()
Not used very often but this function can allow you to run multiple functions
consecutively without putting anything to a halt. It uses intervals to store the time
since the last operation or function was running. Here is a code snippet.
// Record the time of the first event
unsigned long firstEventTime = 0;

// Record the time of the second event

unsigned long secondEventTime = 0;

// Set the interval for the first event to occur

const long firstEventInterval = 5000;

// Set the interval for the second event to occur

const long secondEventInterval = 1000;

void setup() {
// Any necessary setup can be done here
}

void loop() {
// Record the current time since the program started
unsigned long currentTime = millis();
// Check if it's time for the first event
if (currentTime - firstEventTime >= firstEventInterval) {
// Update the time of the first event
firstEventTime = millis();
// Execute code for the first event every 5 seconds
}

// Check if it's time for the second event

if (currentTime - secondEventTime >= secondEventInterval) {
// Update the time of the second event
secondEventTime = millis();
// Execute code for the second event every 1 second
}
}
Example Sketch
Sketch is the whole project you created in your IDE. Note that when you save your
project, it is saved with the extension of .ino. Let us see a sample sketch to turn on the
LED.
int sensor in = A1; //analog pin at A1
int ledPin = 5; //digital pin at pin 5
int sensorValue;
//configurations the sketch
void setup() {
Serial.begin(9600); //initialize serial communication
pinMode(ledPin, OUTPUT); //define output pin
}

void loop() {
sensorValue = analogRead(sensorPin);
Serial.print("Sensor value is: "); //print a message
Serial.println(sensorValue); //print the value to the serial monitor
//conditional statements
if(sensorValue < 100) {
digitalWrite(ledPin, HIGH); //turn on the LED on pin 5.
}
else{
digitalWrite(ledPin, LOW);
}
}
Why choose Arduino?
We need to know the reason for selecting Arduino over other devices so let us study
some advantages of Arduino.
 Arduino is the best choice for starting your programming journey in electronics. Its
easy-to-use interface allows users to build simple projects on their own.
 There is no need for experience or hands-on experience in electronics before
starting work on Arduino. Anyone with a genuine interest in Arduino can begin
learning through simple tutorials and some guidance. These tutorials are available
free of cost for creating some beginner-level and advanced projects.
 Arduinos offer a wide range of options. You can use Arduino alone to create some
projects or you can add some extra features by integrating it with other devices like
Raspberry Pie.
 Arduino is an open-source tool that can be accessed from different locations and
platforms. Due to the inexpensive nature of Arduinos, they can be used on different
microcontrollers like Atmel's ATMEGA 16U2 microcontrollers.
 Depending on the need of your project, you can avail of any Arduino that satisfies
the needs. These Arduino are available in different designs that offer different size
ranges, power, and specifications.
What Can You Do With an Arduino?
Arduino finds its applications in various fields due to their ability to perform different
things. Let us see some of its applications:
 Arduinos are used in 3D printing where they perform the task of selecting how the
printing will be performed.
 Arduinos are used for creating basic designs by makers, designers, hackers, and
creators across the globe to create some great projects. Some of the projects are
Laser Turret Midi Controller, Retro Gaming With an OLED Display, and Traffic Light
Controller.
 Arduinos are used by college students to understand programmable
electronics and to explore their interest in programming.
 Arduinos are used in the field of robotics for programming robots and adding basic
features like sensing and responding to environmental conditions.
 Arduino is used in IoT(Internet of Things) since it can collect information using
sensors. The collected data is then processed and transmitted for developing various
smart devices.
Structure of Arduino
Different Arduino are designed to serve different purposes but some basic components
are needed in every Arduino. Note that Arduino Uno is the most used board and is the
most common choice for different users. Let us study the internal structure of the
Arduino Uno model.
 Processor: 16 Mhz ATmega16U2
 Flash memory: 32KB
 Ram: 2KB
 Voltage Needed: 5V
 Input Voltage: 7-12V
 Analog input pins: 6
 Number of digital I/O: 14 with 6 of them being PWM pins
Components of Arduino
Let's study the basic components of Arduino:
Breadboard: Breadboards are used to provide a base for setting up the connecting
components together. If you look at a breadboard, is a plastic block made up of holes
that are left for making connections using wires. The internal of the breadboard
consists of different connections that are hidden. They are generally used for smaller
circuits
LEDs(Light Emitting Diode): LEDs are small devices that illuminate when a small
voltage is supplied to them. These LEDs come in a variety of colors ranging from red to
green. These LEDs can be used for testing minimum voltages since they don't burn for
a long period.
Photo Resistor: Many Arduinos contain a photoresistor that is used for measuring
changes in light using Arduino.
Tactile Switch: This switch resembles a button that is used to open or close a circuit
like any other switch. When the button is turned on, the voltage of Arduino increases
from 0V to +5V. This voltage change acts as a trigger for the Arduino and an Arduino
detects this change momentarily since the switch is then turned off when the button is
released.
Microcontroller: An Arduino consists of a microcontroller that controls the whole
functioning of the Arduino by generating an apt output corresponding to the input code.
Depending on the type of Arduino board you are using, you can select a microcontroller
that fits well.
Resistors: Resistors are used to resist the flowing electricity. Resistors are often
bought to set a limit to the current flowing in the circuit thereby protecting the
components of the circuit from getting burnt due to excessive current.
Jumper Wires: Jumper wires are thin wires covered with a plastic covering for
insulation. These wires are used for connecting different components in the
breadboard.
Setting Up Your Arduino
This is an essential step since it allows your computer to communicate with Arduino.
Make sure you have a tested and working Arduino board before connecting it to your
computer. Any duplicate Arduino will need some modifications in the installation
process. Let us see how to connect the Arduino to the computer for the execution of
the code.
Installing the Arduino Software Package
To install the Arduino software, you need to visit the official website and download the
latest version that is valid for your computer. Here is a list of steps to be followed for
installing Arduino Integrated Development Environment (IDE).
Windows Setup
 Plug in your board to the computer and you will see a driver installation setup box
on the screen. You can grant access to connect the Arduino to the computer and
case it fails :
o Go to the Start Menu and select Control Panel.
o Go to System and Security > System. After this open up the device manager.
o If you carefully observe the ports, there will be an open port associated with the
connected Arduino named Arduino UNO (COMxx).
o Right-click on the name (Arduino UNO (COMxx) in this case) and select Update
Driver Software.
o Search for Driver software by selecting Browse my computer.
 Search for the Uno's driver file, which will be named ArduinoUNO.inf, located in
the Drivers folder of the Arduino Software download.
Mac OS
 Use a zipping software to extract the contents of the .zip file associated with the
installed Arduino software
 Open the Arduino software by clicking on the extracted application.
 You don't need to install any additional drivers for the Arduino UNO in MAC OS and it
will run fine.
Installing the Arduino Software on Package Ubuntu/Linux
Installation on Ubuntu/Linux is a bit different since it involves dealing with some
commands. Here are the steps.
 Install gcc-avr and avr-libc using this command:
sudo apt-get install gcc-avr avr-libc
 Install and configure openjdk-6-jre, you can skip this step if it is already present :
sudo apt-get install OpenJDK-6-jre
sudo update-alternatives --config java
 Select the correct JRE corresponding to the Arduino.
 Visit the official website and download the Arduino Software suitable for Linux. You
can use these commands.
tar xzvf arduino-x.x.x-linux64.tgz
cd arduino-1.0.1
./arduino
Running the Arduino Software
Since our software has been installed, it is our time to check whether the setup is
correct and that our Arduino is working well. To do this, we will use the "Blink" sample
application
Once the Arduino application has been installed on your device, open the software for
the associated Arduino. Then follow these steps:
 Connect your Arduino board to your computer using some connecting cable.
 The software icon will appear at the location where you have installed the Arduino
application. Double-click it to open the interface.
 Follow the order File > Examples > Basics > Blink
 When you open the application, the screen will show the code written for your
Arduino. Now you have to get this code on the Arduino
 To upload code on Arduino select Tools-> Board and then choose the required
Arduino model like Arduino Uno.
 After this, you need to specify the serial port from which the board will take data. Go
to Tools-> Serial Port and then select the port. Windows users can select port COM3
or similar, and Mac or Linux users can select /dev/tty.usbmodem.
 Carefully look at the left portion of the screen and you will see the Upload button,
click on it.
 After a brief period you will observe receiving(RX) and transmitting(RX) LEDs on the
Arduino illuminating with a "Done uploading" message on the screen.
 If this doesn't appear, there must be some error so follow the steps carefully again.
Conclusion
We have seen how Arduino is a very useful and budget-friendly device that can be used
for making basic projects. The ability of Arduino to provide a programming interface
and allow features like the detection of data from the environment makes it a great
choice for designers, and artists. Despite the versatilities offered, there are certain
restrictions associated with Arduino, and developments are being made in the Arduino
design. Readers are advised to try some basic projects to enhance their understanding
of the subject.

Intel Galileo Board for Internet of Things Development

Introduction to Galileo Board

o Intel Galileo Board is the first board based on Intel® architecture designed to be
hardware and software pin-compatible with Arduino shields designed for the Uno
R3.
o Galileo is a microcontroller board based on the Intel® QuarkSoC X1000 Application
Processor, a 32-bit Intel Pentium-class system on a chip (datasheet).
o Important pins such as digital pins, analog, GND pin, power header, UART all pins
of Galileo are all in the same place as on the Arduino Uno R3.
o It supports shields that operate at either 3.3V or 5V. The operating voltage of
Galileo is 3.3V. However, a jumper on the board enables voltage translation to 5V
at the I/O pins.
o The Galileo board is compatible with the Arduino Integrated Development
Environment software (IDE),which makes usability and introduction a snap.
o In addition to Arduino hardware and software compatibility, the Galileo board has
several PC industry standard I/O ports and features to expand native usage and
capabilities beyond the Arduino shield ecosystem.
Physical Features
o A full sized mini-PCI Express slot,
 o 100Mb Ethernet port,
o Micro-SD slot
o RS-232 serial port
o USB Host port
o USB Client port and
o 8MByte NOR flash come standard on the board
o Reset button to reset the sketch and any attached shields
Intel Galileo Specs (Technical Features)
o 400MHz 32-bit Intel® Pentium instruction set architecture (ISA)-compatible
processor o 16KBytes on-die L1 cache
o 512KBytes of on-die embedded SRAM
o Simple to program: Single thread, single core, constant speed
o ACPI compatible CPU sleep states supported
o An integrated Real Time Clock (RTC), with an optional 3V “coin cell” battery for
operation between turn on cycles.
o 10/100 Ethernet connector
o Full PCI Express* mini-card slot, withPCIe 0 compliant features
 Works with half mini-PCIecards with optional converter plate
 Provides USB 2.0 Host Port at mini-PCIeconnector
o USB 2.0 Host connector
 Support up to 128 USB end point devices
o USB Device connector, used for programming
 Beyond just a programming port – a fully compliant USB 2.0 Device controller
o 10-pin Standard JTAG header for debugging
o Reboot button to reboot the processor
o Reset button to reset the sketch and any attached shields
Storage options
o Default – 8MByte Legacy SPI Flash main purpose is to store the firmware (or
bootloader) and the latest sketch. Between 256KByte and 512KByte is dedicated
for sketch storage. The download will happen automatically from the development
PC, so no action is required unless there is an upgrade that is being added to the
firmware.
o Default 512KByte embedded SRA, enabled by the firmware by default. No action
required to use this feature.
 o Default 256MByte DRAM, enabled by the firmware by default.
o Optional micro SD card offers up to 32GByte of storage
o USB storage works with any USB 2.0 compatible drive
o 11KByte EEPROM can be programmed via the EEPROM library.
Power
Intel Galileo is powered via an AC-to-DC adapter, connected by plugging a 2.1mm
center-positive plug into the board’s power jack. The recommended output rating of the
power adapter is 5V at up to 3Amp.
Electrical Summary

Input Voltage 5V

14 (of which 6 provide PWM

Digital I/O Pins
output)

Analog Input Pins 6

Total DC Output Current on

80 mA
all I/O lines

DC Current for 3.3V Pin 800 mA

DC Current for 5V Pin 800 mA

Communication
Intel Galileo has a number of facilities for communicating with
o a computer
o Arduino
o Other microcontrollers.
o Galileo provides UART TTL (5V/3.3V) serial communication, which is available on
digital pin 0 (RX) and 1 (TX).
o In addition, a second UART provides RS-232 support and is connected via a 3.5mm
jack.
Wearables development in an IoT world
 Wearables, IoT sensor trends
MCU innovations are quietly packing more intelligence in smaller form factors. These
advancements are enabling OSs to be utilized in small form factor sensor devices such
as wearables.
Microcontroller (MCU) innovations are quietly packing more intelligence in smaller form
factors. These advancements are enabling operating systems (OSs) to be utilized in
small form factor sensor devices, such as wearables.
Wearables, IoT sensor trends
Intelligence is increasing in smaller form factor wearables and sensor devices. Today’s
MCUs are now small and cost-effective enough to be used in a wide variety of sensor
applications where price and size requirements previously excluded them. As MCUs
proliferate in these applications, so too have the OSs that run on them.
Adding an OS to a wearable opens new doors in terms of features, functions, and time to
market benefits. The question becomes whether it is enough to just use any OS that
targets the MCU, or if the OS must be tuned for these devices?
RoweBots recently announced availability of a “WearableOS” at the Wearables
Technology Conference that is specifically tuned for wearable and Internet of Things-
enabled (IoT-enabled) devices.
Emergence of the “WearableOS”
RoweBots’ history includes the Unison RTOS used in military systems where security and
reliability are critical. This history includes traditional embedded system practices
involving porting and running the OS on a specific processor architecture, adding drivers
for board support packages (BSPs), and providing APIs for embedded application
development.
Over the last 10 years RoweBots has been working in the IoT space as well. “Our OS
products target MCUs and small microprocessors with a goal of creating an efficient
design," says Kim Rowe, CEO of RoweBots. "Real-time requirements have diminished
over time. Flash and RAM sizes have become a critical cost factor for embedded and IoT
designs.”
Rowe mentions two key areas of focus for their WearableOS:
1. Being able to do more in a small package. Support for lean product development
(LPD) is a cornerstone of RoweBots' IoT OSs (Figure 1).
2. Open APIs based on embedded Linux allow RoweBots OS products to integrate
libraries that match the functions needed and available resources on the platform.
Figure 1. Lean product development (LPD) is a development methodology for reducing
product engineering cycles and cost that is central to RoweBots' WearableOS.
“We took a more packaged approach to delivering a real-time operating system (RTOS)
when developing the WearableOS," Rowe explains. "We didn’t stop at a chip support
package for a controller. We added packages that deal with specific vertical markets.
Wearables is one of these targets. The three key pillars for this effort were hardware
support for wearable products, optimized software design, and enabling faster time to
market.”
The world of wearables needs a complete package of OS/processor support, connectivity,
storage, and cloud connectivity. In addition, security requirements are important, and
RoweBots’ history with the Unison RTOS in the military industry gave them a leg up in
understanding security considerations. Much of this has also been incorporated in to the
WearableOS.
Rowe mentions the importance of not stopping development at an MCU OS and driver
support for the sensors that a manufacturer provides. “Sensor support needs to be
general," he says. "It’s important to allow the developer to utilize any number of
temperature sensors, accelerometers, or whatever peripherals are required to allow
choice and maintain hardware independence and abstraction.”
Power management
Power management is another critical component. Some MCUs are simply designed as
very low power with little to no power modes. Therefore, power management of most
MCUs is simple when compared to the capabilities of an ARM processor, for example.
“MCU manufacturers typically try to maximize all-around power efficiency," Rowe says.
"However, in some of the more advanced processors, power management has taken a
leap. There are a lot more options in terms of what you can do to go to sleep and wake
up again.”
Some of the options Rowe alludes to involve integrated power modes in hardware that
can be updated, as well as certain silicon events that are capable of waking up software.
Wearable connectivity
Wireless connectivity is another important feature of the WearableOS. Kim mentioned
some interesting applications in the sports industry where different radio types are
needed. “Our OS needs to support three different types of radios depending on the
sport," Row says. "One is for individual operation like bike racing. Wearables are used to
provide metrics on speed, vitals, and crash information. These kinds of things use
Bluetooth Low Energy (BLE). Another extension is road races or marathons where you
don’t want to be carrying around a phone. These applications need Long Range (LoRa)
radios. Football or basketball applications are a third example. These applications use
802.14, which allows group communication capabilities among teammates”.
Rowe adds that RoweBots has provided LTE and Wi-Fi solutions to the traditional
embedded markets for a while. In the past they have used proprietary connectivity as
well, like satellite phones. An example application is the Caterpillar low cost tracker.
Wearable security
Two key aspects for wearables are communications/information security and software
update security and authentication. The Unison RTOS has shipped with complete over-
the-air (OTA) update capabilities for the past six years, with security a focus throughout.
These features were adopted in their WearableOS environment.
“Everyone wants to talk about security, no one wants to pay for it yet," says Rowe. "We
decided about 5 years ago that it was unacceptable to have fielded systems with our OS
that weren’t secure. So we bundled in the important security features at no cost.
"For example, transport layer security (TLS) communications comes standard, along with
secure SFTP for file transfer and SSH for remote control (login and command execution),"
he adds.
Secure boot is another critical aspect for wearables. This is important to ensure OTA
update security. Depending on the processor features, it can be incorporated in
hardware or emulated in software.
For example, i.MX6 (NXP/Freescale) and RZ (Renesas) secure boot technology and other
similar mechanisms embed keys in hardware and to provides embedded encryption
unique to that silicon, which is used to sign and encrypt software images. This allows
platforms with secure boot technology to authenticate the source of the image and know
that the image itself has not been corrupted, and also provides a mechanism to roll back
to the previous release if the update doesn’t happen successfully or if there are errors in
operation. All this results in a more reliable, secure system.
Rowe further acknowledges that the company continues to work towards enhancing the
security of its products, including the recent completion of a Microsoft Azure package
that includes secure communications over the HTTP, MQTT, and AMQP protocols, as well
as for the cloud platform itself.
Graphics and user interfaces
Perhaps the most interesting challenges relating to wearables and smart sensors are the
unique graphics and user interfaces (UIs). On larger systems there are lots of capabilities
and screen area for fancy graphics and user interaction. These systems also tend to be
very power hungry.
On the smaller end, for watch and wrist wearables, Rowe notes that the WearableOS
typically uses vendor-recommended packages or a third-party vendor for ultra-low-power
graphics and UI components. Not surprisingly, programming wearables is a lot like
traditional embedded system programming using application libraries and the C/C++
programming language with an Eclipse variant or embedded Integrated Development
Environment (IDE).
BSD sockets network, file I/O, and embedded Linux and POSIX-compliant APIs speed
development in these builds. Kim mentioned cites an embedded Linux application
example that was been ported, run, and tested on the OS in 2 days using these tools.
Upon porting, benchmarking showed that the same application running on their OS had a
50 percent increase in frame rate due to the significantly lower overhead of the
WearableOS versus embedded Linux.
Another exciting example of miniaturizing wearables with similar capabilities involves an
eSight technologies product. These are glasses that help people with specific types of
peripheral or myopic blindness conditions see normally. eSight puts a camera on the
bridge of your nose to do auto exposure and compensation for your specific sight
deficiency. On your hip you have zoom and pan controls. The wearable puts the image
up on a tiny screen in front of your eye. This technology allows people with sight
problems to see normally and has literally changed lives.
Summary
Wearable and IoT sensor and device development requires a combination of hardware,
software, and the ability to reuse them in order to decrease time to market while not
sacrificing performance and reliability. Whether you’re developing a medical, factory
floor, or wearable device that must be integrated into a larger IoT environment, building
with a vertical OS environment can improve reliability and security with more finished,
tested code, while also decreasing time to market and maintaining flexibility for
component and hardware vendors.

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