Fire fighting final report

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INDEX
I. Introduction
1. Robot
1.1. What is a robot?
1.2. Types of robot based on control
1.3. Applications
1.4. Benefits of robot to mankind
1.5. Characteristicof robot
2. Controllers
2.1. Microcontrolller
2.1.1. Need for a microprocessor or a microcontroller
2.1.2. What can a microcontroller do?
2.2. Motor controller
2.2.1. Motor controller and it’s need
2.2.2. Choosing a motor controller
2.3. D.C.motors
2.3.1. DC motor types
2.3.2. D.C.motor charateristics
3. Sensors
3.1. Types of sensors
3.2. Applications of sensors
4. Manual control
4.1. Manual control types
II. Data and Methodology
1. Components
1.1. Hardware specification
1.2. Software specification
2. Controller’s used
2.1. Atmega8
2.2. Motor driver circuit
2.3. DC motor control direction
2.4. RF Encoder & Decoder
3. Block diagram of fire fighting robot
4. Designing the robot
5. Circuit diagram of fire fighting robot
6. Working principle
7. Transmitter and Receiver

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III. Result
1. Aplications
2. Advantages and Disadvantages
3. Future scope
4. Conclusion
5. References

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FIRE FIGHTING ROBOT
ABSTRACT
In today’s commercial, industrial and domestic world, Automation plays an important role,
it is actually an arrangementof different elements in order to regulate, direct, senseand
command itself to achieve a desired result. “Fire Fighting Robot” projectemploys the
electrical thermostat technology for the controlling the fire 24 hrs. The system is cost
effective, has a wide application which when implement can show good and effective
result. Itcan be use deliberately in industrial applications, commercial and in domestic
sectors wherethe requirement of automatic work demands. Synchronization of various
equipment involvein the systemi.e Thermostat Sensor, water jet, wireless remote and
wireless android device WiFi enabled Camera. This is mean to simulate the real-world
operation of Robot performing a fire extinguishing function. Fuzzy logic provided an
appropriatesolution to the otherwisecomplex task of mathematically deriving an exact
model for the non-linear controlsystem upon which conventional control techniques could
then be applied. Making Robot wireless increases the effective area of operation, thereby
making it possibleto controlthe robotfrom remote location. Keeping all above factors in
mind the Robot is capable of being remotely controlled and live video buffering i.e
possessing a multimedia interface was convinced and developed.
Keywords: ThermostatTechnology, Modern FireExtinguisher, WiFi Camera Technology,
Wireless navigation.

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I. INTRODUCTION
This is movement-based robot. It uses to sense the fire and spreads the water our that direction.
vehicle is loaded with the water tanker and a pump which is controlled by wireless
communication to throw water.
.
nd destruction of property and the
environment.
Robotics is one of the fastest growing engineering fields of today. Robots are designed to
remove the human factor from labor intensive or dangerous work and also to act in inaccessible
environment. The use of robots is more common today than ever before and it is no longer exclusively
used by the heavy production industries. The need Fire extinguisher Robot that can detect and extinguish a
fire on its own is long past due. With the invention of such a device, people and property can be saved at a
much higher rate with relatively minimal damage caused by the fire. Our task as engineers was to design
and build a prototype system that could autonomously detect and extinguish a fire. Also aims at
minimizing air pollution. In this Project we design a wireless controlled Robot. It is the Robot that can
move through a model structure, find a burning and then extinguish it with help of a Water Jet.
Robots are intelligent machines that can be controlled according to need. If a multimedia
interface is provided, its further aids in navigation of the robot. Making the robot wireless increases the
effective area of operation, thereby making it possible to control the robot from a remote location.
Keeping all the above factors in mind the, a robot capable of being remotely controlled through the
Internet and possessing a multimedia interface, was conceived and developed. I have used very basic
concept here, easy to understand from the prospective of beginners or for the masters of this field. The
need for a device that can detect and extinguish a fire on its own is long past due. Many house fires
originate when someone is either sleeping or not home. With the invention of such a device, people and
property can be saved at a much higher rate with relatively minimal damage caused by the fire.
In this Project we design a Fuzzy based Microcontroller controlled Robot. It is the Robot
that can move through a model structure, find lit candle and then extinguish it with help of a Blower. This
is meant to simulate the real-world operation of a Robot performing a fire extinguishing function in an
oilfield. Fuzzy logic provided an appropriate solution to the otherwise complex task of mathematically
deriving an exact model for the non-linear control system upon which conventional control techniques
could then be applied. Keeping all above factors in mind the Robot is capable of being remotely controlled
and live video buffering i.e. possessing a multimedia interface was convinced and developed.

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Robot is defined as a mechanical design that is capable of performing human tasks or
behaving in a human-like manner. Building a robot requires expertise and complex programming. It’s about
building systems and putting together motors, flame sensors and wires, among other important
components. A fire fighter robot is one that has a small fire extinguisher added to it. By attaching a small
fire extinguisher to the robot, the automation put out the fire by human controlling. This paper covers the
design and construction of a robot that is able to sense and extinguish fire. This robot implements the
following concepts: environmental sensing, proportional motor control. This robot processes information
from its various sensors and key hardware elements via microcontroller. It uses thermistors or ultraviolet
or visible sensors to detect the fire accident. A robot capable of extinguishing a simulated tunnel fire,
industry fire and military applications are designed and built. The project helps to generate interests as
well as innovations in the fields of robotics while working towards a practical and obtainable solution to
save lives and mitigate the risk of property damage.
Fire fighters face risky situations when extinguishing fires and rescuing victims, it is an
inevitable part of being a fire fighter. In contrast, a robot can function by itself or be controlled from a
distance, which means that firefighting and rescue activities could be executed without putting fire fighters
at risk by using robot technology instead. In other words, robots decrease the need for fire fighters to get
into dangerous situations. This robot provides fire protection when there is a fire in a tunnel or in an
industry by using automatic control of robot by the use of microcontroller in order to reduced loss of life
and property damage. This robot uses dc motors, castor wheel, microcontroller, sensors, pump and
sprinkler. Microcontroller is the heart of the project. Microcontroller controls all the parts of the robot by
the use of programming. In this robot as the fire sensor senses the fire, it sends the signal to
microcontroller; since the signal of the sensor is very weak the amplifier is used so that it can amplify the
signal and sends it to microcontroller.

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1. ROBOT:
1.1 What is a robot?
Robotsare physical agentsthatperformtasksbymanipulatingthe physical world.Theyare equippedwith
sensorstoperceive theirenvironmentandeffectorstoassertphysical forcesonit.Asmentionedbefore
Robotscan be putintothree maincategories:manipulators,mobile robotsandhumanoidrobots.
 Robotics and AI:
Artificial intelligence isatheory.The base objectisthe agentwhois the "actor". It is
realizedinsoftware.Robotsare manufacturedas hardware.The connectionbetweenthose twois
that the control of the robot isa software agentthat readsdata fromthe sensorsdecideswhattodo
nextandthendirectsthe effectorstoact in the physical world.
 Sensor:
A sensorisa device thatmeasuresaphysical quantityandconvertsitintoa signal
whichcan be read by an observerorbyan instrument.
For example,amercury-in-glassthermometerconvertsthe measuredtemperature intoexpansion
and contractionof a liquidwhichcanbe readon a calibratedglasstube.A thermocouple converts
temperature toanoutputvoltage whichcan be read bya voltmeter.Foraccuracy, mostsensorsare
calibratedagainstknownstandards.
 Effectors:
Effectorsare the meansby whichrobotsmanipulate the environment,moveand
change the shape of theirbodies.Inrobotics,endeffectoristhe device atthe endof a roboticarm,
designedtointeractwiththe environment.The exactnature of thisdevice dependsonthe
applicationof the robot.Inthe strict definition,whichoriginatesfromserial roboticmanipulators,
the endeffectormeansthe lastlink(orend) of the robot.At thisendpointthe toolsare attached.In
a widersense,endeffectorscanbe seenasthe part of a robot that interactswiththe work
environment.Thisdoesnotrefertothe wheelsof amobile robotorthe feetof a humanoidrobot
whichare alsonotendeffectors—theyare partof the robot'smobility.
In short we can say that robot is an electromechanical device which can perform various tasks.
It may be human controlled or automated. It finds it's uses in all aspects of our life.

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1.2. Types of robot based on control:
Types of Robot:
 Redundant Robots:
Six degrees of freedom are, in principle, enough to manipulateobjects in
space with three possible independenttranslationsand three independentrotations. But,
with a given architecture of a robot arm and a given working environment, restrictions of
workspace, dexterity and obstacles call for additionaldegree(s) of freedom. In such cases,
as a human being uses additionalfreedoms of the body to supplementthe capabilities of the
arm for enhancing thereach, manipulateobjects comfortably and reach below the table or
around the corner objects, additionaldegrees of freedom can be provided in the robot arm
with extra joints and links. Such robots are called redundantrobots (because they use more
inputsthan necessary) and are used for the purposes of workspace enhancementand
avoidanceof singularities and obstacles. With a redundantrobot, a particular point can be
reached in infinite numberof ways — to choose one of those infinite ways is the problem of
redundancyresolution, which is solved by optimizing the performance.
 Space Robots:
Robots in space applicationsare light, can handlegreater masses and
have a special characteristic that, unlike robots on earth, their frames are not fixed, rather
they float with the rest of the robot, together with the space vehicle.
Manual Semi - autonomous Autonomous
Robot
Wired Wireless Pre -programmed Self-learning

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 Flexible Robots:
Truly speaking, all solid bodies are flexible. Conventional modelling of
robot manipulatorsneeds to consider the links of a robot as rigid, for which the deflections
have to be negligible from the viewpoint of positional accuracy. Consequently, the links are
to be designed stronger than necessary and heavy. But, from a physical point of view, it is
not necessary and we should not mind the links being flexible as long as they are within
elastic limits and we know their behavior. So, the recent interest has been to work with
flexible robots and to take advantageof their light weight by incorporating their flexibility
into the mathematicalmodel which, of course, complicates the dynamics of the system --- a
price to be paid for the advantagegained.
 Parallel-actuated Robots and Closed-loop Robots:
The traditional serial chain robots, due to their cantilever structure,
have less load carrying capacity. Actuations off the base aggravatethis problem and make
the robot bulky. Consequently, the serial robots tend to bend at high load and vibrate at high
speed. Though theypossess a large workspace, the positioning capabilityis rather poor. So,
where high load carrying capacity and precise positioning is of prime concern, an
alternative is provided by parallel-actuated and closed-loop robots which haveattracted
tremendous research interest in the last 15 years. As a human being uses both arms to
handlea heavy load, three fingers in parallel for doing a precise work like writing and as
animalbody is supported on four legs with provision of in-parallel actuation at the leg
joints, robot manipulatorsalso can be designed with the end effector (hand) connected to the
frame by parallelchains of joints and links having the actuationsdistributed among the
various chainsor legs. The most celebrated among the parallel manipulatorsis the six-
degrees-of- freedom parallelmanipulatorcalled the Stewart platform which has its end-
effector connected to the ground by six extensible legs having ball-socket joints at the ends,
the extensions of the legs being done by six linear actuators. Parallel robots, in general,
provide high structural rigidity and load carrying capacity, good positioning capabilities
and have less vibration. But they generally have restricted workspaces and their kinematics
and dynamicsis quite complicated to study and analyse. Typical applicationsof parallel
robots include applicationswhere high load capacity and precise positioning are required,
use as an assembly workstation, dexterous wrist and micromanipulators. Theapplication of
the concept of parallel actuation has uses in cooperating robots and in multi-fingered
gripping and manipulation.

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 Walking Robots:
While manipulation robots manipulate objects by utilizing the freedom
available at the joints, mobile robots can carry objects to greater distances by body
movement. In ordinary life, we use trains, automobiles and animals for conveyance.
Similarly, in robotics, we have tracked, wheeled and legged vehicles. Though all of these
have their own applications, walking machines have enjoyed the maximum research interest
due to their versatility over terrain irregularities and greater mobility, and work is mostly
focused on machines walking on two to six legs. Till now, most of these walking machines
have succeeded mostly in laboratory conditions and have achieved little breakthrough on
completely unstructured ground, but the attempts in this direction promise a high potential.
Recently BARC has developed a walking machine with six legs (presented in National
Convention on Industrial Problems in Machines and Mechanisms 1994) which moves
forward and can take turns also, but the walking speed is quite low. A challenging field of
research is biped locomotion which gives rise to a problem of stability, which is evident as
equilibrium of a body with less than three supports is precarious. The ease of biped
locomotion in human beings can be attributed to their erect body structure, the extent and
nature of the surface of the foot and an extremely smart nervous system — conditions
simulating which in machines is a really challenging task.
 Model-based Control:
Thetraditional control strategy of robot manipulatorsis completely error
driven and shows poor performance at high-speeds, when the high dynamicforces act as
disturbances. Thecurrent trend is towards model-based control, where the dynamicforces
are incorporated in the control strategy as feed forward gains and feedback compensations
along with the servo-controller which is required only to take care of external noise and
other factors not included in the dynamicmodel of the robot. As is expected, the model-based
control scheme exhibits better performance, but demandshighercomputationalload in real
time. A particulararea of model-based control is adaptivecontrol, which is useful when the
dynamicparameters of the robot are not well-known a priori. The controller adaptsitself
during execution of tasks and improves the values of the dynamicparameters.

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 Force Control:
Conventionalcontrol schemes primarily concentrate on position control.
But certain tasks (e.g. cleaning a window pane) requires the maintenanceof some required
contact forces. Cur- rent trend is to control the force in such directions (in such
applications) and position in other directions. The use of compliance (flexibility) also is
getting popularin control. In applicationslike insertion of a peg into a hole, if the positional
accuracy is poor, the forces stemming from such errors tend to correct the position, if some
compliance is provided at the wrist.

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1.3. Application:
Nowadays, robots do a lot of different tasks in many fields and the number of jobs entrusted to robots is
growing steadily. That's why the best ways how to divide robots into types is a division by their application.
They are:
*Industrial robots:
Industrial robots are robots used in an industrial manufacturing environment. Usually these are articulated
arms specifically developed for such applications as welding, material handling, painting and others. If we
judge purely by application this type could also include some automated guided vehicles and other robots.
*Domestic or household robots:
Robots used at home. This type of robots includes many quite different devices such as robotic vacuum
cleaners, robotic pool cleaners, sweepers, gutter cleaners and other robots that can do different chores.
Also, some surveillance and telepresence robots could be regarded as household robots if used in that
environment.
*Medical robots:
Robots used in medicine and medical institutions. First and foremost - surgery robots. Also, some
automated guided vehicles and maybe lifting aides.
*Service robots:
Robots that don’t fall into other types by usage. These could be different data gathering robots, robots
made to show off technologies, robots used for research, etc.
*Military robots:
Robots used in military. This type of robots includes bomb disposal robots, different transportation robots,
reconnaissance drones. Often robots initially created for military purposes can be used in law
enforcement, search and rescue and other related fields.
*Entertainment robots:
These are robots used for entertainment. This is a very broad category. It starts with toy robots such as
robosapien or the running alarm clock and ends with real heavyweights such as articulated robot arms
used as motion simulators.

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*Space robots:
I’d like to single out robots used in space as a separate type. This type would include robots used on the
International Space Station, Canadarm that was used in Shuttles, as well as Mars rovers and other robots
used in space.
*Hobby and competition robots:
Robots that you create. Line followers, sumo-bots, robots made just for fun and robots made for
competition.

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1.4. Benefits of robot to mankind:
 Productivity
Robots produce more accurate and high quality work. Robots rarely make mistakes and are
more precise than human workers. They can produce a greater quantity in a short amount
of time. They can work at a constant speed with no breaks, days off, or holiday time. They
can perform applications with more repeatability than humans.
 Safety
Robots save workers from performing dangerous tasks. They can work in hazardous
conditions, such as poor lighting, toxic chemicals, or tight spaces. They are capable of lifting
heavy loads without injury or tiring. Robots increase worker safety by preventing accidents
since humans are not performing risky jobs. Work cells provide safety features, separating
the worker from harm way.
 Savings
Robots save time by being able to produce a greater magnitude of products
They also reduce the amount of wasted material used due to their accuracy
Robots save companies money in the long run with quick ROIs (return on investment), fewer
worker injuries (reducing or eliminating worker’s comp), and with using less materials.

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1.5. Characteristic of robot:
A robot has these essential characteristics:
 Sensing First of all your robot would have to be able to sense its
surroundings. It would do this in ways that are not unsimilar to the way that
you sense your surroundings. Giving your robot sensors: light sensors (eyes),
touch and pressure sensors (hands), chemical sensors (nose), hearing and
sonar sensors (ears), and taste (tongue) will give your robot awareness of its
environment.
 Movement a robot needs to be able to move around its environment.
Whether rolling on wheels, walking on legs or propelling by thrusters a robot
needs to be able to move. To count as a robot either the whole robot moves,
like the Sojourner or just parts of the robot moves, like the Canada Arm.

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2. Controllers
2.1. Microcontrollers:
A microcontroller is a compact microcomputer designed to govern the operation of
embedded systems in motor vehicles, robots, office machines, complex medical
devices, mobile radio transceivers, vending machines, home appliances, and various
other devices. A typical microcontroller includes a processor, memory, and
peripherals. A microcontroller is a self-contained system with peripherals, memory
and a processor that can be used as an embedded system. Most programmable
microcontrollers that are used today are embedded in other consumer products or
machinery including phones, peripherals, automobiles and household appliances for
computer systems. Due to that, another name for a microcontroller is "embedded
controller". Some embedded systems are more sophisticated, while others have
minimal requirements for memory and programming length and a low software
complexity.
Input and output devices include solenoids, LCD displays, relays, switches and
sensors for data like humidity, temperature or light level, amongst others.

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2.1.1. Need for a microprocessor or microcontroller:
A microprocessor is the heart of computer systems and a microcontroller is the heart of an
embedded system self. Most communication, digital entertainment and portable devices are
controlled by either of them. A designer should know what types of components he needs, ways to
reduce production costs and it must be product reliable.
One must first understand the difference between a microprocessor and microcontroller, so that
the person can select the right core for the robot.
A microprocessor typically refers specifically to the device/component whose job it is to fetch
commands, interpret the command opcodes, and execute the commands. In a modern
microprocessor, this basically means the ALU, the register set, instruction pipeline, and the
microprocessor control circuitry to perform the Von-Neumann "fetch-decode-execute" cycle. One
generalization is that microprocessors require an external bus and discrete memory devices to
interface with (separate from internal registers, and whatever built in caching memory the
microprocessor contains).
Figure: Block diagram of microprocessor and microcontroller
Figure courtesy: http://www.rfwireless-world.com/images/microcontroller-versus-
microprocessor.jpg
Microcontrollers - on the other hand, are more generalized devices which contain a
microprocessor, a main system bus, ram, room/flash, and typically a set of other devices such as a
programmable interrupt controller, analog/digital converters, any number of general-purpose IO
devices, communications interfaces, etc.

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2.1.2. What can a microcontroller do?
Although microcontrollers can seem rather limited at first glance, many complex actions can be
achieved by setting the pins HIGH and LOW in a clever way. Nevertheless, creating very complex
algorithms (such as advanced vision processing and intelligent behaviors) or very large programs
may be simply impossible for a microcontroller due to its inherent resource and speed limitations.
For instance, in order to blink a light, one could program a repeating sequence where the
microcontrollers turn a pin HIGH, waits for a moment, turns it LOW, waits for another moment and
starts again. A light connected to the pin in question would then blink indefinitely.
In a similar way, microcontrollers can be used to control other electrical devices such as actuators
(when connected to motor controllers), storage devices (such as SD cards), Wi-Fi or Bluetooth
interfaces, etc. As a consequence of this incredible versatility, microcontrollers can be found in
everyday products. Practically every home appliance or electronic device uses at least one (often
many) microcontroller. For instance, TV sets, washing machines, remote controls, telephones,
watches, microwave ovens, and now robots require these little devices to operate.
Unlike microprocessors (e.g. the CPU in personal computers), a microcontroller does not require
peripherals such as external RAM or external storage devices to operate. This means that although
microcontrollers can be less powerful than their PC counterpart, developing circuits and products
based on microcontrollers is much simpler and less expensive since very few additional hardware
components are required.
It is important to note that a microcontroller can output only a very small amount of electrical
power through its pins; this means that a generic microcontroller will likely not be able to power
electrical motors, solenoids, large lights, or any other large load directly. Trying to do so may even
cause physical damage to the controller.

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2.2. Motor Controllers:
2.2.1. What are a motor controller and its need?
A motor controller is an electronic device that acts as an intermediate device between a
microcontroller, a power supply or batteries, and the motors. Although the microcontroller (the
robot’s brain) decides the speed and direction of the motors, it cannot drive them directly because
of its very limited power (current and voltage) output. The motor controller, on the other hand, can
provide the current at the required voltage but cannot decide how fast the motor should turn.
Thus, the microcontroller and the motor controller have to work together in order to make the
motors move appropriately. Usually, the microcontroller can instruct the motor controller on how
to power the motors via a standard and simple communication method such as UART or PWM.).
2.2.2. Choosing a Motor Controller
Motor controllers can only be chosen after you have selected your motors/actuators. Also, the
current a motor draws is related to the torque it can provide: a small DC motor will not consume
much current, but cannot provide much torque, whereas a large motor can provide higher torque
but will require a higher current to do so.
The first consideration is the motor’s nominal voltage. DC motor controllers tend to offer a voltage
range. For example, if your motor operates at 3V nominal, you should not select a motor controller
that can only control a motor between 6V and 9V. This will help you cross off some motor
controllers from the list.
Once you have found a range of controllers that can power the motor with the appropriate voltage,
the next consideration is the continuous current the controller will need to supply. You need to find
a motor controller that will provide current equal to or above the motor’s continuous current
consumption under load. Should you choose a 5A motor controller for a 3A motor, the motors will
only take as much current as they require. On the other hand, a 5A motors is likely to burn a 3A
motor controller. Many motor manufacturers provide a DC motor’s stall current, which does not
give you a clear idea of the motor controller you will need. If you cannot find the motor’s
continuous operating current, a simple rule of thumb is to estimate the motor’s continuous current
at about 20% to 25% of the stall current. All DC motor controllers provide a maximum current
rating – be certain this rating is about double that of the motor’s continuous operating current.
Note that when a motor needs to produce more torque (for example going up an incline), it
requires more current. Choosing a motor controller with built-in over current and thermal
protection is a very good choice.

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2.3. DC motors:
A DC motor in simple words is a device that converts direct current (electrical energy) into
mechanical energy. A DC motor's speed can be controlled over a wide range, using either a variable
supply voltage or by changing the strength of current in its field windings. Small DC motors are used
in tools, toys, and appliances. Nearly all
Figure: Simple DC motor
.Figure courtesy:
http://jazeerabotics.com/media/catalog/product/cache/1/image/1200x1200/9df78eab33525d08d
6e5fb8d27136e95/s/i/simple_dc_motor_4fa6bfb69f6a3.png
Types of DC motors have some internal mechanism, either electromechanical or electronic; to
periodically change the direction of current flow in part of the motor. Most types produce rotary
motion; a linear motor directly produces force and motion in a straight line, it can run in both the
directions.
2.3.1. DC motor types:
There are three basic types of dc motors:
(1) Series motors,
(2) Shunt motors, and
(3) Compound motors.
They differ largely in the method in which their field and armature coils are connected.
 Series DC Motor:
In the series motor, the field windings, consisting of a relatively few turns of heavy wire, are
connected in series with the armature winding. Because of the low resistance in the windings, the
series motor is able to draw a large current in starting. This starting current, in passing through both
the field and armature windings, produces a high starting torque, which is the series motor's
principal advantage. The speed of a series motor is dependent upon the load.

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 Shunt DC Motor:
In the shunt motor the field winding is connected in parallel or in shunt with the armature winding.
The resistance in the field winding is high. Since the field winding is connected directly across the
power supply, the current through the field is constant. The field current does not vary with motor
speed, as in the series motor and, therefore, the torque of the shunt motor will vary only with the
current through the armature. The torque developed at starting is less than that developed by a
series motor of equal size. The speed of the shunt motor varies very little with changes in load.
When all loads are removed, it assumes a speed slightly higher than the loaded speed. This motor is
particularly suitable for use when constant speed is desired and when high starting torque is not
needed.
 Compound DC Motor:
The compound motor is a combination of the series and shunt motors. There are two windings in
the field: a shunt winding and a series winding. The shunt winding is composed of many turns of
fine wire and is connected in parallel with the armature winding. The series winding consists of a
few turns of large wire and is connected in series with the armature winding. The starting torque is
higher than in the shunt motor but lower than in the series motor. Variation of speed with load is
less than in a series-wound motor but greater than in a shunt motor. The compound motor is used
whenever the combined characteristics of the series and shunt motors are desired.
2.3.2. DC motor characteristics:
The power of the dc motor lies in its versatility and ease with which a variety of speed-torque
characteristics can be obtained, and the wide range of speed control which is possible without the
need of elaborate control schemes while a high level of operating efficiency is maintained. A simple
motor has six parts, as shown in the diagram below: Armature or rotor, Commutator, Brushes, Axle,
Field magnet, DC power supply of some sort.
Figure: Parts of an electric DC motor
Figure courtesy: http://www.mutleyshangar.com/reviews/jack/dcm/img/MotorDiagram.jpg

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Principle of operation:
Consider a coil in a magnetic field of flux density B. When the two ends of the coil are connected
across a DC voltage source, current I flow through it. A force is exerted on the coil as a result of the
interaction of magnetic field and electric current. The force on the two sides of the coil is such that
the coil starts to move in the direction of force. In an actual DC motor, several such coils are wound
on the rotor, all of which experience force, resulting in rotation. The greater the current in the wire,
or the greater the magnetic field, the faster the wire moves because of the greatest forced created.
Figure: Fleming’s left hand rule to determine the direction of force acting on the armature
conductors of DC motor
Figure courtesy: http://electrical4u.com/electrical/wp-content/uploads/2013/03/fleming-left-hand-
rule-2.png
At the same time this torque is being produced, the conductors are moving in a magnetic field. At
/dt) as shown indifferent positions, the flux linked with it changes, which causes an emf to be
induced (e = d/dt). This voltage is in opposition to the voltage that causes current flow through the
conductor and is referred to as a counter-voltage or back emf.
The value of current flowing through the armature is dependent upon the difference between the
applied voltage and this counter-voltage. The current due to this counter-voltage tends to oppose
the very cause for its production according to Lenz’s law. It results in the rotor slowing down.
Eventually, the rotor slows just enough so that the force created by the magnetic field (F = Bil)
equals the load force applied on the shaft. Then the system moves at constant velocity.
Torque Developed:
The equation for torque developed in a DC motor can be derived as follows. The force on one coil
of wire:
F =i l x B (Newton)
Here l and B are vector quantities. Since B =/A where A is the area of the coil.

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3. Sensors:
A sensor is a device that detects and responds to some type of input from the physical environment. The
specific input could be light, heat, motion, moisture, pressure, or any one of a great number of other
environmental phenomena. The output is generally a signal that is converted to human-readable display at
the sensor location or transmitted electronically over a network for reading or further processing.
3.1. Different types of Sensors:
The most frequently used different types of sensors are classified based on the quantities such as Electric
current or Potential or Magnetic or Radio sensors, Humidity sensor, Fluid velocity or Flow sensors, Pressure
sensors, Thermal or Heat or Temperature sensors, Proximity sensors, Optical sensors, Position sensors,
Chemical sensor, Environment sensor, Magnetic switch sensor , etc.
Figure: Different types of Sensors

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3.2. Different Types Of Sensors With Their Applications:
Typical applications of different types of sensors such as application of Speed sensor for synchronizing the
speed of multiple motors, Temperature sensor application for industrial temperature control, application
of the PIR sensor for automatic-door-opening system, Ultrasonic sensor application for distance
measurement, etc., are discussed below with their block diagrams.
 Speed Sensor
Sensors used for detecting speed of an object or vehicle is called as Speed sensor. There are
different types of sensors to detect the speed such as Wheel speed sensors, speedometers, LIDAR,
ground speed radar, pitometer logs, doppler radar, air speed indicators, pitot tubes and so on.
Application of Speed Sensor:
For speed synchronization of multiple motors in industries using wireless technology is a typical
application of the speed sensor. One of the multiple motors in the industry is considered as a main
motor which act as transmitter and remaining motors acting as receivers, will follow the speed of
the main motor. The main motor and receiver motors used in this project are BLDC motors that are
controlled using PWM control with the radio frequency wireless communication mode.
RPM is given to each motor shaft which has an IR sensor mounted and a closed loop is obtained by
feeding this output to controller in the circuit. Full speed will be displayed on display unit and
required speed of all motors can be obtained by entering the desired percentage using the keypad.
This entered percentage is matched with running RPM by maintaining appropriate DC power to
motor with automatic adjustment of pulse width output of microcontroller. Thus, by varying speed
of transmitting motor, we can change the speed of all motors using this technology.
 Temperature Sensor:
A device which gives temperature measurement as an electrical signal is called as Temperature
sensor. This electrical signal will be in the form of electrical voltage and is proportional to the
temperature measurement. There are different types of sensors used for measuring temperature,
such as Contact type temperature sensors, Non-contact type temperature sensors. These are again
subdivided as Mechanical temperature sensors like Thermometer and Bimetal. Electrical
temperature sensors like Thermistor, Thermocouple, Resistance thermometer and Silicon band gap
temperature sensor.

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 PIR Sensor:
An electronic sensor used for measuring the infrared light radiation emitted from objects in its field
of view is called as a PIR sensor or Pyroelectric sensor. Every object that has a temperature above
absolute zero emit heat energy in the form of radiation radiating at infrared wavelengths which is
invisible to the human eye, but can be detected by special purpose electronic devices such as PIR
motion detectors.
Figure: Passive Infrared Sensor
PIR sensor itself is split into two halves, which are sensitive to IR and whenever object comes in the
field of view of the sensor, then positive differential change will be produced between two halves
with the interception of the first half of the PIR sensor. Similarly, if the object leaves the field of
view, then negative differential change will be produced. PIR or Passive Infrared sensor is named as
passive because it doesn’t emit any energy or radiation for detecting the radiation. There
are different types of sensors used for detecting the motion and these PIR sensors are classified
based on angle (wide area) over which they can detect motion of the objects like 110degrees,
180degrees and 360degress angles.
Application of PIR Sensor:
Automatic Door Opening System is a typical application of PIR sensors which is intended for
automatic door closing and opening operations based on body movement near the door. If a body
movement is present near the door, then infrared radiation emitted from the body will cause the
sensor to produce sensing signal which is fed to microcontroller. The door motor is then controlled
and operated by the microcontroller through driver IC. Thus, if anybody comes near to door, then a
command will be sent by microcontroller for opening door and a time delay is set for closing door
automatically. This is intended for operating doors of shopping malls, theatres and hotels.

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 Ultrasonic Sensor:
The principle of ultrasonic sensor is similar to sonar or radar in which interpretation of echoes from
radio or sound waves to evaluate the attributes of a target by generating the high-frequency-sound
waves (around 40kHz). The transducer used for converting energy into ultrasound or sound waves
with ranges above human hearing range is called an ultrasonic transducer.
Application of Ultrasonic Sensor:
The distance measurement at inaccessible areas is a typical application of ultrasonic sensors. The
circuit consists of an ultrasonic module, LCD display and microcontroller. The ultrasonic module is
interfaced with the microcontroller and this ultrasonic transducer consists of a transmitter and
receiver.
The waves transmitted by transducer are received back again after the waves are reflected back
from the object. The velocity of sound is considered for calculating time taken for sending and
receiving waves. The distance is calculated by executing a program on microcontroller, and then it
is displayed on the LCD display.

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4. Manual control:
The definition we have chosen for a “robot” requires the device to obtain data about its
environment, make a decision, and then take action accordingly. This does not exclude the
option of a robot being semi-autonomous (having aspects which are controlled by a human
and others which it does on its own). A good example of this is a sophisticated underwater
robot; a human control the basic movements of the robot while an on-board processor
measures and reacts to underwater currents in order to keep the robot in the same position
without drifting. A camera onboard the robot sends video back to the human while onboard
sensors may track the water temperature, pressure and more. If the robot loses
communication with the surface, an autonomous program may kick-in causing it to surface.
If you want to be able to send and/or receive commands from your robot, you will need to
determine its level of autonomy and if you want it to be tethered, wireless or fully
autonomous.
4.1. Types of manual control:
1. Direct Wired Control
The easiest way to control a vehicle is with a handheld controller physically connected to the
vehicle using a cable (i.e. a tether). Toggle switches, knobs, levers, joysticks and buttons on this
controller allow the user to control the vehicle without the need to incorporate complex
electronics. In this situation, the motors and a power source can be connected directly with a
switch in order to control its forward/backwards rotation. Such vehicles usually have no intelligence
and are considered to be more “remote controlled machines” than “robots”.
Advantages
 The robot is not limited to an operating time since it can be connected directly to the mains
 There is no worry about loss of signal
 Minimal electronics and minimal complexity
 The robot itself can be light weight or have added payload capacity
 The robot can be physically retrieved if something goes wrong (very important for underwater
robots)
Disadvantages
 The tether can get caught or snagged (and potentially cut)
 Distance is limited by the length of the tether
 Dragging a long tether adds friction and can slow or even stop the robot from moving.

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2. Wired Computer Control
The next step is to incorporate a microcontroller into the vehicle but continue to use a tether.
Connecting the microcontroller to one of your computer’s I/O ports (e.g. a USB port) allows you to
control its actions using a keyboard (or keypad), joystick or another peripheral device. Adding a
microcontroller to a project also may require you to program how the robot reacts to the input.
Instead of using a laptop or desktop computer, netbooks are often a desirable choice because of
their low price, small size and low weight.
Advantages
 Same advantages as with direct wired control
 More complex behaviours can be programmed or mapped to single buttons or commands.
 Larger controller choice (mouse, keyboard, joystick, etc.)
 Added onboard intelligence means it can interface with sensors and make certain decisions on its
own.
Disadvantages
 Cost is higher than a purely tethered robot because of the added electronics
 Same disadvantages as with direct wired control.
3. Ethernet
A variation on computer control would be to use an Ethernet interface. A robot that is physically
connected to a router (so it could be controlled via the Internet) is also possible (though not very
practical) for mobile robots. Setting-up a robot that can communicate using the internet can be
fairly complex, and more often than not, a Wi-Fi (wireless internet) connection is preferable. A
wired and wireless combination is also an option, where there is a transceiver (transmit and
receive) connected physically to the internet and data received via the internet is then sent
wirelessly to the robot.
Advantages
 Robot can be controlled through the Internet from anywhere in the world
 The robot is not limited to an operating time since it could use Power over Ethernet (PoE).
 Using Internet Protocol (IP) can simplify and improve the communication scheme.
 Same advantages as with direct wired computer control
Disadvantages
 Programming involved is more complex
 The tether can get caught or snagged (and potentially cut)
 Distance is limited by the length of the tether
 Dragging a long tether adds friction and can slow or even stop the robot from moving.

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4. Wireless Infrared
Infrared transmitters and receivers cut the cables connecting the robot to the operator. This is
usually a milestone for beginners. Infrared control requires “line of sight” in order to function; the
receiver must be able to “see” the transmitter at all times in order to receive data. Infrared remote
controls (such as universal remote controls for televisions) are used to send commands to an
infrared receiver connected to a microcontroller which then interprets these signals and controls
the robot’s actions.
Advantages
 Low cost
 Simple TV remote controls can be used as controllers
Disadvantages
 Needs to be line of sight
 Distance is limited.
5. Radio Frequency (RF)
Commercially available Remote Control (R/C) units use small microcontrollers in the transmitter
and receiver to send, receive and interpret data sent via radio frequency (RF). The receiver box has
a PCB (printed circuit board) which comprises the receiving unit and a small servo motor controller.
RF communication requires either a transmitter matched/paired with a receiver, or a transceiver
(which can both send and receive data). RF does not require line of sight and can also offer
significant range (transmission distance). Standard radio frequency devices can allow for data
transfer between devices as far away as several kilometers and there is seemingly no limit to the
range for more professional RF units.
XBee and Zigbee modules use RF for communication, but allow the user to vary many of the
communication parameters involved. These modules have a specific footprint (layout) and are only
produced by certain companies. Their main advantage is that they provide a very robust easy to set
up link and take care of all of the communication protocol details.
Many robot builders choose to make semi-autonomous robots with RF capability since it allows the
robot to be as autonomous as possible, provide feedback to a user and still give the user some
control over some of its functions should the need arise.
Advantages
 Considerable distances possible
 Setup can be straightforward
 Omni directional (impeded but not entirely blocked by walls and obstructions)
Disadvantages
 Very low data rate (simple commands only)
 Pay attention to the transmission frequencies – they can be shared.

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6. Bluetooth
Bluetooth is a form of RF and follows specific protocols for sending and receiving data. Normal
Bluetooth range is often limited to about 10m though it does have the advantage of allowing users
to control their robot via Bluetooth-enabled devices such as cell-phones, PDAs and laptops (though
custom programming may be required to create an interface). Just like RF, Bluetooth offers two-
way communication.
Advantages
 Controllable from any Bluetooth enabled device (usually additional programming is necessary) such
as a Smartphone, laptop, desktop etc.
 Higher data rates possible
 Omnidirectional (does not need line of sight and can travel a little through walls)
Disadvantages
 Devices need to be “paired”
 Distance is usually about 10m (without obstructions)
7. Wi-Fi
Wi-Fi is now an option for robots; being able to control a robot wirelessly via the internet presents
some significant advantages (and some drawbacks) to wireless control. In order to set up a Wi-Fi
robot, you need a wireless router connected to the internet and a Wi-Fi unit on the robot itself. For
the robot, you can also use a device that is TCP/IP enabled with a wireless router.
Advantages
 Controllable from anywhere in the world so long as it is within range of a wireless router
 High data rates possible
Disadvantages
 Added programming required
 Maximum range is usually determined by the choice of wireless router.

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8. GPRS / Cellular
Another wireless technology that was originally developed for human to human communication,
the cell phone, is now being used to control robots. Since cellular frequencies are regulated,
incorporating a cellular module on a robot usually requires added patience for programming as well
as an understanding of the cellular network system and the regulations.
Advantages
 Robot can be controlled anywhere it has a cellular signal
 Direct satellite connection is possible
Disadvantages
 Setup and configuration can be complex – NOT for beginners
 Each network has its own requirements / restrictions
 Cellular service is not free; usually the more data you transmit/receive the more money you will
need to pay.
 System is not (yet) well setup for robotics use.
9. Autonomous
The next step is to use the microcontroller in your robot to its full potential and program it to react
to input from its sensors. Autonomous control can come in various forms: pre-programmed with no
feedback from the environment, limited sensor feedback and finally complex sensor feedback. True
“autonomous control” involves a variety of sensors and code to allow the robot to determine by
itself the best action to be taken in any given situation.
The most complex methods of control currently implemented on autonomous robots are visual and
auditory commands. For visual control, a robot looks to a human or an object in order to get its
commands. Getting a robot to turn to the left by showing a piece of paper with arrow pointing left
is a lot harder to accomplish than one might initially suspect. An auditory command such as “turn
left” also requires quite a bit of programming. Programming a variety of complex commands like
“get me a drink from the fridge” or “get my shoes, they’re near the front door” is no longer fantasy
but requires a very high level of programming, and a lot of time.
Advantages
 This is “real” robotics
 Tasks can be as simple as blinking a light based on one sensor readings to landing a spacecraft on a
distant planet.
Disadvantages
 It’s only as good as the programmer; if it’s doing something you don’t want it to do, the only option
you have is to check your code, modify it and upload the changes to the robot.

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II. DATA AND METHODOLOGY
1. Components
In this project we will be using these components:
1.1. HardwareSpecifications:
 8051 series Microcontroller
 Relay
 Motor Driver(L293D)
 Power supply circuit
 Reset and oscillator circuit
 Light sensor
 DC motor
 RF module
 DC water pump
 Push button
 Transistor
 Encoder IC
 Decoder IC
 Resistors
 Diode
 LED
 IR sensor
 RS232 (MAX232 IC)
 Crystal (11. 0592 MHZ)
 Vehicle body
 Water tank
 Spray tube
 12 Volt Battery
Software Specifications
 Keil µVision IDE
 MC Programming Language: Embedded C

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Hardware specification
 Microcontroller:
A microcontroller is a single chip that contains the processor (the CPU), non-volatile memory for the
program (ROMor flash), volatile memory for input and output (RAM), a clock and an I/O control unit. It is a
powerful device, which is capable of executing various tasks and interfacing with other hardware evices.
The controller used in this project is AT89S52.The AT89S52 is a low-power, high-performance CMOS 8-bit
microcontroller with 8K bytes of in-system programmable Flash memory.
 Microcontroller8051:
The Intel 8051 microcontrollerisone of the most popular general-purpose microcontrollersinuse today.The
successof the Intel 8051 spawnedanumberof cloneswhichare collectivelyreferredtoasthe MCS-51 familyof
microcontrollers,whichincludeschipsfromvendorssuchasAtmel,Philips,Infineon,andTexasInstruments.ITis40
pinIC 8051 The Intel 8051 isan 8-bit microcontrollerwhichmeansthatmostavailable operationsare limitedto8
bits.There are 3 basic "sizes"of the 8051: Short, Standard,andExtended.The ShortandStandardchips are often
available inDIP(dual in-linepackage) form,butthe Extended8051 modelsoftenhave adifferentformfactor,and
are not"drop-incompatible".All thesethingsare called8051 because theycan all be programmedusing8051
assemblylanguage,andtheyall share certainfeatures(althoughthe differentmodelsall have theirownspecial
features).
 Some of the featuresthathave made the 8051 popularare:
4 KB on chipprogram memory,128byteson chipdata memory(RAM),4registerbanks,128userdefinedsoftware
flags,8-bitdatabus,16-bitaddressbus,16bittimers(usually2,butmayhave more,or less),3internal and2 external
interrupts, Bitaswell asbyte addressable RAMareaof 16 bytes,Four8-bitports,(shortmodelshave two8-bit
ports),16-bitprogramcounteranddata pointer,1Microsecondinstructioncycle with12MHz Crystal,8051 models
may alsohave a numberof special,model-specificfeatures,suchasUART,ADC, Op_ Amps,etc...itisa verypowerful
microcontroller.
Pin Diagram of 8051 Microcontroller
8051 microcontroller families (89C51, 8751, DS89C4xO, 89C52) come in different packages
like quad-flat package, leadless chip carrier and dual-in-line package. These all packages consist
of 40 pins which are dedicated to several functions such as I/O, address, RD, WR, data and
interrupts. But, some companies offer a 20-pin version of the microcontrollers for less demanding
applications by reducing the number of I/O ports. Nevertheless, a vast majority of developers use
the 40-pin chip.
The pin diagram of 8051 microcontroller consists of 40 pins as shown below. A total of 32 pins are set away
into four Ports such as P0, P1, P2 and P3. Where, each port contains 8 pins. Therefore, the microcontroller
8051’s pin diagram and explanation is given below:

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 Port1 (Pin1 to Pin8):
Port1 includes pin1.0 to pin1.7 and these pins can be configured as input or output pins.
 Pin 9 (RST):
Reset pin is used to Reset 8051 Microcontroller by giving a positive pulse to this Pin.
 Port3 (Pin 10 to 17):
The Port3 Pins are similar to port1 pins and can be used as universal Input or output pins. These
pins dual-function Pins and the function of each Pin is given as:
 Pin 10 (RXD):
RXD pin is a Serial Asynchronous Communication Input or Serial synchronous
Communication Output.
 Pin 11 (TXD):
Serial Asynchronous Communication Output or Serial Synchronous Communication clock Output.
 Pin 12 (INT0):
Input of Interrupt 0
 Pin 13 (INT1):
Input of Interrupt 1
 Pin 14 (T0):
Input of Counter 0 clock
 Pin 15 (T1):
Input of Counter 1 clock
 Pin 16 (WR):
Writing Signal to write content on external RAM.
 Pin 17 (RD):
Reading Signal to read contents of external RAM.
 Pin 18 and 19 (XTAL2, XTAL1):
X2 and X1 pins are input output pins for the oscillator. These pins are used to connect an internal
oscillator to the microcontroller.

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 Pin 20 (GND):
Pin 20 is a ground pin.
 Port2 (Pin 21 to Pin28):
Port2 includes pin21 to pin28 which can be configured as Input Output Pins. But, this is only
possible when we don’t use any external memory. If we use external memory, then these pins will
work as high order address bus (A8 to A15).
 Pin 29 (PSEN):
This pin is used to enable external program memory. If we use an external ROM for storing the
program, then logic 0 appears on it, which indicates Micro controller to read data from the
memory.
 Pin 30 (ALE):
Address Latch Enable pin is an active high-output signal. If we use multiple memory chips, then this
pin is used to distinguish between them. This Pin also gives program pulse input during
programming of EPROM.
 Pin 31 (EA):
If we have to use multiple memories then the application of logic 1 to this pin instructs the
Microcontroller to read data from both memories: first internal and then external.
 Port 0 (Pin 32 to 39):
Similar to the port 2 and 3 pins, these pins can be used as input output pins when we don’t use any
external memory. When ALE or Pin 30 is at 1, then this port is used as data bus: when the ALE pin
is at 0, then this port is used as a lower order address bus (A0 to A7)
 Pin40 (VCC):
This VCC pin is used for power supply.
 Relay:
Arelay is an electrically operated switch. Many relays use an electromagnet to
mechanically operate a switch, but other operating principles are also used, such as solid-
state relays. Relays are used where it is necessary to control a circuit by a separate low-
power signal, or where several circuits must be controlled by one signal. The first relays
were used in long distance telegraph circuits as amplifiers: they repeated the signal coming
in from one circuit and re-transmitted it on another circuit. Relays were used extensively in
telephone exchanges and early computers to perform logical operations.
A type of relay that can handle the high power required to directly controlan electric motor
or other loads is called a contactor. Solid-state relays controlpower circuits with no moving
parts, instead using a semiconductor device to perform switching. Relays with calibrated
operating characteristics and sometimes multiple operating coils are used to protect
electrical circuits fromoverload or faults; in modern electric power systems thesefunctions
are performed by digital instruments still called "protective relays".

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Magnetic latching relays require one pulseof coil power to move their contacts in one
direction, and another, redirected pulse to move them back. Repeated pulses from the
same input have no effect. Magnetic latching relays are useful in applications where
interrupted power should not be able to transition the contacts.
Magnetic latching relays can haveeither single or dual coils. On a single coil
device, the relay will operate in one direction when power is applied with one
polarity, and will resetwhen the polarity is reversed. On a dual coil device,
when polarized voltage is applied to the reset coil the contacts will transition.
AC controlled magnetic latch relays have single coils that employ steering
diodes to differentiate between operate and reset commands

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 Motor Driver(L293D):
Microcontrollerhasverylowcurrentoutputit cannot drive currentconsumingsources,suchlike
motor hence motordrivercircuitrequires.We canimplementthiscircuitusingtransistororrelated
driverIC.NotificationLEDcan directlydrive withcurrentlimitingresistorthroughmicrocontroller.
Motors can be connectedwithmotordriverICoutputitcan be submersible pumporbasic
movementsmotor.
• L293D is a dual H-bridgemotor driver integrated circuit(IC).
• Motor drivers act as currentamplifiers since they take a low-currentcontrol
signal and providea higher-currentsignal.
• This higher currentsignal is used to drive the motors.
 L293D contains two inbuilt H-bridge driver circuits. In its common mode
of operation, two DC motors can be driven simultaneously, both in
forward and reverse direction.

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The Motor driver which we are using in our projectis L293D. Itis a monolithic integrated
high voltage, high currentfour channel driver designed to accept standard DTL or TTL logic
levels and driveinductive loads (such as relays solenoids, DC and stepping motors) and
switching power transistors. This deviceis suitable for use in switching applications at
frequencies up to 5 kHz
 ProvidesinterfacingbetweenMCUand wheel motor
 Quadruple highcurrenthalf H drivers
 Designedtoprovide bidirectionalcurrentupto 1A
 Wide supplyvoltage :4.5-36V
 Power Supply Circuit:
A powersupplyisanelectronicdevice thatsupplieselectrical energytoan electrical load.Here microcontroller,
sensorandaudiocircuitoperate withDC 5V, motordrivercircuitoperateswithDC12V supplyandthissupplyis
providedby12V stepdowntransformerwithrectifiers(tocharge batteryof 12V) and requiredtoconvertinto DC 5V
by regulator.The 12V DC to convertinto 5V by LM7805 regulatorformicrocontroller.The LEDisusedfor indication
purpose,asshowthe level of liquidbyON/OFFandresistorisusedinseriesforcurrentlimitingpurpose
 Reset and Oscillator Circuit:
Anymicrocontrollerrequiresoscillationfrequencyforitsoperationitcanbe internal forfew microcontrollersand
for fewitprovide external also.Thismicrocontrollerrequiresexternaloscillatorfrequency.Resetcircuitrequiresfor
the restart programfrom beginningitusedwhenmicrocontrollerhangsorif we requiredtostopthe running
conditionwithbeginningprocess.

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 Light Sensor:
Light sensorisa passive device whichconvertslightenergyintoelectrical signal.Itiscommonlyknownas
photoelectricdevice,because itconvertslightenergyorphotonsintoelectricity.Lightsensorsare more commonly
knownas “PhotoelectricDevices”or“PhotoSensors”because the convertlightenergy(photons)intoelectricity
(electrons).LightsensorisconnectedatportRA worksto sense the lighttodetectphysical inputandmicrocontroller
takesactionas programmedincontroller.
 DC Motor:
It isan electricmotorthat convertselectrical energyintomechanical energyanditiscalledaDC Motor because it
workson directcurrent.12V DC powersupplyisrequiredforthe DC Motor for itsoperation.InthisprojectDCMotor
isusedto operate wheelsof the vehicle.

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 RF Module: (RF Tx-Rx)
The RF module operates at Radio Frequency. The corresponding
frequency range varies between 30 kHz & 300 GHz. In this RF system,
the digital data is represented as variations in the amplitude of
carrier wave. This robot is a Fire Fighting Robot and it is controlled by
Remote controller. For this purpose, we are using microcontroller
and it is interfaced to RF Module. The RF Module is used to receive
commands send by user remotely through remote control.
 Main Factors Affecting RF Module’s Performance:
As compared to the other radio-frequency devices, theperformanceof an RF module will
depend on severalfactors like by increasing the transmitter’s power a large communication
distance will be gathered. However, which will result in high electrical power drain on the
transmitter device, which causes shorter operating life of the battery powered devices.
Also, by using this device at higher transmitted power will create interference with other RF
devices.
 Features of RF Transmitter and Receiver:
Receiver frequency: 433MHz, Receiver typicalsensitivity: 105Dbm, Receiver current supply:
3.5mA, Receiver operating voltage: 5V, Low power consumption, Transmitter frequency
range: 433.92MHz,Transmitter supply voltage: 3V~6V, Transmitter outputpower:
4~12Dbm

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Features of RF:
• Range in open space (Standard Conditions): 100 Meters
• RX Receiver Frequency: 433 MHz
• RX Typical Sensitivity: 105Dbm
• RX Supply Current: 3.5 mA
• RX IF Frequency: 1MHz
• Low Power Consumption
• Easy for Application
• RX Operating Voltage: 5V
• TX Frequency Range: 433.92 MHz
• TX Supply Voltage: 3V ~ 6V
• TX Out Put Power: 4 ~ 12Dbm
RF Receiver:
An RF Receiver module receives the modulated RF signal, and demodulates it.
The transmitted data is received by an RF receiver operating at the same
frequency as that of the transmitter. The RF receiver in the robot receives the
information and decodes it and gives information to the microcontroller about
which fire sensor is activated.

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RF Transmitter:
An RF transmitter module is a small PCB subassembly capable of transmitting
a radio wave and modulating that wave to carry data. Transmitter modules
are usually implemented alongside a micro controller which will provide data
to the module which can be transmitted. An RF transmitter receives serial
data and transmits it wirelessly through RF through its antenna connected at
pin4. The transmission occurs at the rate of 1Kbps - 10Kbps. [3] The data from
the comparator is transmitted to the receiver using the RF transmitter
module.
 DC Water Pump:
Pump is a mechanical device which is used to pump water on to
the fire to extinguish it. It uses a simple motor to pump water
DC powered pumps use direct current from motor or battery to move fluid in a variety of
ways. The main advantage of DC pumps over AC pumps is that they can operate directly
from a battery, making them more convenient and portable.

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 Push button:
A push-button (also spelled pushbutton) or simply button is a simple switch mechanism for
controlling some aspect of a machine or a process. Buttons are typically made out of hard
material, usually plastic or metal.
 Transistor:
A transistor is a semiconductor with a solid and non-moving part to pass a charge. It can amplify
and switch electrical power and electronic signals. Transistors are made of semiconductor
material with three or more terminals used to connect to an external circuit.

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 Encoder IC (HT-12E)
HT12E converts the parallel inputs into serial output. It encodes the 12 bits parallel data into serial
for transmission through an RF transmitter. These 12 bits are divided into 8 address bits and 4
data bits.
HT12E has a transmission enable pin which is active low. When a trigger signal is received on TE
pin, the programmed addresses/data are transmitted together with the header bits via an RF or an
infrared transmission medium. HT12E begins a 4-word transmission cycle upon receipt of a
transmission enable. This cycle is repeated as long as TE is kept low. As soon as TE returns to
high, the encoder output completes its final cycle and then stops.
The encoder which we are using in our project is HT12E. HT12E is an encoder
integrated circuit of 212series of encoders. It is mainly used in interfacing RF-
circuits and IR-circuits. It encodes the 12 bits parallel data into serial form for
transmission through an RF transmitter. These 12 bits are divided into 8
address bits and 4 data bits. HT12E has a transmission enable pin which is
active low.

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 Decoder IC (HT12D)
HT12D converts the serial input into parallel outputs. It decodes the serial addresses and
data received by, say, an RF receiver, into parallel data and sends them to output data
pins. The serial input data is compared with the local addresses three times continuously.
The input data code is decoded when no error or unmatched codes are found. A valid
transmission in indicated by a high signal at VT pin.
HT12D is capable of decoding 12 bits, of which 8 are address bits and 4 are data bits. The data on
4 bit latch type output pins remain unchanged until new is received.
The decoder which we are using in our project is HT12D. HT12D is a decoder
integrated circuit that belongs to 212series of decoders. The decoder is
connected to RF receiver and it will indicate which fire sensor is activated.
HT12D converts the serial input into parallel outputs. HT12D is capable of
decoding 12 bits, of which 8 are address bits and 4 are data bits. The data on 4
bits latch type output pins remain unchanged until new is received. The
chosen pair of encoder/decoder should have same number of addresses and
data format.

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 Resister:
A resistor is an electrical component that limits or regulates the flow of electrical current in an
electronic circuit. Resistors can also be used to provide a specific voltage for an active device
such as a transistor.
 Diode:
The most common function of a diode is to allow an electric current to pass in one direction (called the
diode's forward direction), while blocking it in the opposite direction (the reverse direction). As such, the
diode can be viewed as an electronic version of a check valve.

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 LED:
A light-emitting diode (LED) is a two-lead semiconductor light source. It is a p–n junction diode that emits
light when activated. When a suitable voltage is applied to the leads, electrons are able to recombine with
electron holes within the device, releasing energy in the form of photons.
 IR sensor:
IR Photo Diodes are used as sensors. These sensors are connected to ADC pins
of the microcontroller. IR Photo diodes are connected in reverse bias to be
operated as photo diodes otherwise they will be operated as normal diodes.
The voltage variations of the sensors are given as inputs to the Micro controller
and accordingly the robot is operated.

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 RS 232 (MAX 232 IC):
What is MAX232?
Max232 is designed by Maxim Integrated Products. This IC is widely used in RS232
Communication systems in which the conversion of voltage level is required to make TTL
devices to be compatible with PC serial port and vice versa. This chip contains charge pumps
which pumps the voltage to the Desired Level. It can be powered by a single +5-volt power
supply and its output can reach +_7.5 volts. MAX232 comes in 16 Pin Dip and many other
packages and it contains Dual Drivers. It can be used as a hardware layer convertor for 2
systems to communicate simultaneously. Max232 is one of the versatile IC to use in most of
the signal voltage level conversion problems
Construction of MAX232:
Mostly MAX232 used in 16-pin DIP package. it consists of 3 major blocks. It can only be
powered by 5 volts to make it power supply compatible with most of the embedded systems.
First block is the voltage doubler in this ic switched capacitor techniques is used to make the
voltage double. Once the voltage is doubled second block will converts that voltage to +10
and -10. The third block consists of 2 transmitters and 2 receivers which actually convert the
voltage levels.

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External components:
Max232 requires minimum 4 external capacitor. Their Value can range from 1uf to 10uf and16 volts or
more rating. There are many different versions of this versatile ic available each of them Require different
capacitor value for proper working.
.

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Application and uses of MAX232:
Primely MAX232 is used in Serial communication. Problem arises when we have to
communicate between TTL logic and CMOS logic-based systems. RS232 is internationally
defined standard named as EIA/TIA-232-E and in this standard logic 0 is the voltage
between +3 to +15 and logic 1 is defined as the voltage between -3 to -15.In TTL logic 0 is
defined is by 0 volt and 1 is defined by 5 volt so in this scenario this is a very handy IC to be
incorporated.
Other Applications & Uses
 Battery Powered RS 232 Systems
 Interface Translation
 Low Power Modems
 RS 232 Networks (Multidrop)
 Portable Computing
PC Serial PORT communication by using MAX232 IC:
Desktop and some old Laptops have Serial port which comes in DB9 package. In Most of the
Circuits designer is concerned about the Tx and Rx pins only so the function of the rest of
the pins are not used here mostly.
In the above circuit only one Driver is used and second driver can be used for other purpose.
TTL data is available on pin 12 and pin 11 and these pins can be attached to Microcontroller
or any system which accept TTL logic.

52
Types of MAX232:
1)“MAX232N” where “N” Represent PDIP package Style this package is easy to sold and
most widely used.
2) MAX232D where “D” indicates the SOIC package which is difficult to sold and required
a trained professional to be used correctly.
Common mistakes:
 Interchange Tx and Rx pins on one side of MAX232 at one time.
 Distorted power supply. Use decoupling capacitor to remove distortion.
 Check all the connections again.
 Check the capacitor with capacitance meter.
 Use Tantalum Capacitor for better performance.
 Capacitor voltage rating is less than 16.
 CRYSTAL (11. 0592 MHZ)
PRIMARY USES:
UART clock (6×1.8432 MHz); allows integer division to commonbaud rates
(96×115200baud or 96×96×1,200 baud); commonclock for 8051
microprocessors.

53
 Power supply:
 Consist of 12V car battery, voltage regulator IC 7805 and capacitor as filters.
 Provides regulation of either a fixed positive voltage, a fixed negative voltage or an adjustably set
voltage.

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Software requirements:
• Compilers are programs used to convert a high-level language to object
code. Desktop compilers produce an output object code for the underlying
microprocessor, but not for other microprocessor i.e., the programs
written in one of the HLL like ‘C’ will compile the code to run on the system
for a particular processor like x86 (underlying microprocessor in the
computer).
 For example: compilers for Dos platform is different from the Compilers
for Unix platform So if one wants to define a compiler then compiler is a
program that translates source code into object code

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 Keil µVision IDE:
What is KEIL IDE?
KEIL is a software application that provides extensive facilities for embedded
application developers. It contains a source code editor, software debugger,
assembler, cross compiler, simulator. It supports EmbeddedC and assembly
programming for different microcontrollers suchas 8051,ARM. On successful
compilation of software, KEIL generates a HEX file that can be flashed to 8051
microcontrollers.
Create an 8051 projectusing KEIL uVision
Step 1: Create a project folder on your PC. Later, you are going to store all your project files in this folder.
Step 2: Open KEIL uVision IDE
Step 3: Click Project –> New uVision Project
Step 4: Change path to project folder (step 1). Enter File name, click save

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Step 5: A new popup window appears as shown below. Here you need to select your
microcontroller. If you are using an ATMEL AT89S52 microcontroller, then
find Atmel in Data base and double click on it. You will see a list of Atmel controllers
supported by KEIL.
Select AT89S52 under Atmel, click OK.
step 6: Another popup window will appear saying “Copy Standard 8051 Startup ……..”.
Click No

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Step 7: Now go to File->New.
Step 8: This is an important step. Here you need to save the file.
 For Embedded C, file should save with extension ‘.c’. Ex: test.c
 For assembly code, file should be saved with extension ‘.asm’. Ex: test.asm
Step 9: In this step you are going to Add source files (.c or .asm) to the project.
 Locate project window on the right side of the KEIL IDE.
 Then click [+] symbol next to the Target 1.
 Now right click on Source Group 1, click Add Files to Group ‘Source Group 1’.

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New pop window appears as shown below.
 Select ‘.c’ or ‘.asm’ project files (already created in step8)
 Click Add to add the source file and close the window
Step 10: Now write the source code. Below I wrote an example code.
Step 11: Once coding part is over, press F7 to build the project. You can also
click Project->Buid target to build the project.

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Step 12: You can verify build log at the bottom of the KEIL IDE. In case of Errors and
warnings modify the code and re-compile.
Step 13: It’s time to generate a HEX file. Click Project-> Options for Target “Target 1”
A popup window appears as shown below,
 Click Output (Highlighted).
 Then, select [✓] Create HEX file. Change the HEX file name if you want.

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Step 14: Now build the project (Step 10). You can also rebuild the entire KEIL uVision
project by Clicking Project->Rebuild all target files.
You can find the hex file in the project folder.
You can flash HEX the file to 8051 microcontroller.

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 MC Programming Language: Embedded C
About C Language
C language was developed by Dennis Ritchie in 1969. It is a collection of one or more functions,
and every function is a collection of statements performing a specific task.
C language is a middle-level language as it supports high-level applications and low-level
applications. Before going into the details of embedded C programming, we should know about
RAM memory organization.
Salient features of the language
 C languageis a softwaredesigned with differentkeywords, datatypes, variables,
constants, etc.
 Embedded C is a generic term given to a programminglanguagewritten in C, which
is associated with a particular hardware architecture.
 Embedded C is an extension to the C language with some additionalheader files.
These header files may change from controller to controller.
 The microcontroller 8051 #include<reg51.h> isused.
The embedded system designers must know about the hardware architecture to
write programs. These programs play prominent role in monitoring and controlling
external devices. They also directly operate and use the internal architecture of the
microcontroller, such as interrupt handling, timers, serial communication and other
available features.
Differences between C and Embedded C

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The basic additional features of the embedded software
Data types
The data type refers to an extensive system for declaring variables of different types like integer,
character, float, etc. The embedded C software uses four data types that are used to store data in
the memory.
The ‘char’ is used to store any single character; ‘int’ is used to store integer value, and ‘float’ is
used to store any precision floating point value.
The size and range of different data types on a 32-bit machine is given in the following table. The
size and range may vary on machines with different word sizes.
Data types
Keywords
There are certain words that are reserved for doing specific tasks. These words are known as
keywords. They are standard and predefined in the Embedded C.
Keywords are always written in lowercase. These keywords must be defined before writing the
main program. The basic keywords of an embedded software are given below:
Keywords
sbit: This data type is used in case of accessing a single bit of SFR register.
 Syntax: sbit variable name= SFR bit ;
 Ex: sbit a=P2^1;
 Explanation: If weassign p2.1 as ‘a’ variable, then we can use‘a’ instead of p2.1
anywherein the program, which reducesthe complexity of the program.

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Bit: This data type is used for accessing the bit addressable memory of RAM (20h-
2fh).
 Syntax: bit variable name;
 Ex: bit c;
 Explanation: It is a bit sequencesetting in a small data area that is used by a program
to remember something.
SFR: This data type is used for accessing a SFR register by another name. All the
SFR registers must be declared with capital letters.
 Syntax: SFR variable name= SFR addressof SFR register;
 Ex: SFR port0=0x80;
 Explanation: If weassign 0x80 as ‘port0’, then we can use0x80 instead of port0
anywherein the program, which reducesthe complexity of the program.
SFR Register: The SFR stands for ‘Special Function Register’. Microcontroller 8051
has 256 bytes of RAM memory. This RAM is divided into two parts: the first part of
128 bytes is used for data storage, and the other of 128 bytes is used for SFR
registers. All peripheral devices like I/O ports, timers and counters are stored in the
SFR register, and each element has a unique address.
Advantages of embedded C program
 Its takes less time to develop application program.
 It reducescomplexity of the program.
 It is easy to verify and understand.
 It is portable in naturefrom onecontroller to another.

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 PROGRAM CODE:-
#include<reg51.h>
SBIT SW1=P1^4;
SBIT SW2=P1^5;
SBIT SW3=P1^6;
SBIT SW4=P1^7;
SBIT M1=P1^0;
SBIT M2=P1^1;
SBIT M3=P1^2;
SBIT M4=P1^3;
Void main ();
{
m1=m2=m3=m4=0;
while (1)
{
If (sw1==1)
{
M1=1;
}
else
{
M1=0;
}
if (sw2==1)
{
M2=1;
}
else

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{
M2=0;
}
If (sw3==1)
{
m3=1;
}
else
{
m3=0;
}
If (sw4==1)
{
m4=1;
}
Else
{
m4=0;
}
}
}

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2. Controller’s used
3.
3.1. Atmega8 microcontroller:
ATMEGA16
A microcontroller often serves as the “brain” of a mechatronic system. Like a mini, self-contained
computer, it can be programmed to interact with both the hardware of the system and the user. The
ATmega16 microcontroller we used in our robot is a 40-pin wide DIP (Dual in Line) package chip. This
chip was selected because it is robust. The high-performance, low-power Atmel 8-bit AVR RISC-based
microcontrollercombines 16KB of programmable flash memory, 1KB SRAM, 512B EEPROM, an 8-channel
10-bit A/D converter, and a JTAG interface for on-chip debugging. The device supports throughput of 16
MIPS at 16 MHz and operates between 4.5-5.5 volts.
3.2. Motor Driver Circuit Diagram:
As can be seen in the circuit diagram, pins 4, 5, 13 and 12 of LM293 (U2) areconnected to
GND and the pin 16 (VSS) is connected to 5V. The ‘chip inhibit’ pins (1&9) actas the enable
pins for the input-output pairs on left side and right side of the motor driver, respectively.
Pin 8 (VC) receives the unregulated input supply (Vcc) from the power supply circuit. Itis
noteworthy that this motor driver chip is PWMsupporting, means that if you apply some
voltage in the range 0V to 5V at any input, then it will be scaled up by a factor and will be
available at the corresponding output.
The four input pins (2-7-10-15) receives motor driveinstructions from the MCU. In short,
U2 acts as the interface between the microcontroller (U3) and the dc motors (M1&M2) in
which instructions fromthe microcontroller go into its input pins and the outputs are used
to drive the robot motors.Wecan control the motor direction by suitable commands to the
microcontroller, the microcontroller will give the command to the motor driver, and then
the suitable operation takes place.

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3.3. DC motor control direction:
L293D is a quadruple H- bridge motor driver, as the name suggests it used to drive the DC
motors. This IC works based on the concept of H- Bridge. H-bridge is a circuit which allows the
voltage in either direction to control the motor direction.
There are 4 input pins for L293D. Motors directions depends on the logic inputs applied at this
pins. EN1 and EN2 must be high to drive the 2 DC motors
 N1=0 and IN2=0 -> Motor1 idle
 IN1=0 and IN2=1 -> Motor1 Anti-clock wise direction
 IN1=1 and IN2=0 -> Motor1 Clock wise direction
 IN1=1 and IN2=1 -> Motor1 idle
 IN3=0 and IN4=0 -> Motor2 idle
 IN3=0 and IN4=1 -> Motor2 Anti-clock wise direction
 IN3=1 and IN4=0 -> Motor2 Clock wise direction
 IN3=1 and IN4=1 -> Motor2 idle.
Algorithm
1. Declare P2.0 and P2.2 as inputs and P3.0 and P3.1 as outputs.
2. Now check weather the first button is pressed or not. If pressed, then send logic one to
P3.0.
3. Next check whether the second button is pressed or not. If pressed, then send logic 1 to
P3.1 otherwise send 0 to port 2.
How to Operate?
1. Burn the program to the 8051 microcontroller.
2. Now give the connections as per the circuit diagram.
3. While giving the connections, make sure that there is no direct supply connection from
battery to the controller.
4. Switch on the board supply, now the motor is at stationary condition.
5. Press first button, you can observe that motor will rotate in clockwise direction.
6. Press the second button, now the motor rotates in anticlockwise direction.
7. Switch off the board supply.

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Applications:
 This concept is used in robots to control the robot directions.
 Used to control the speed of the DC motor.
 It is used in the applications where we need to drive the high voltage motors
MOTOR CONTROL RELAY CIRCUIT
•Electrical relaysare interfacedtoMCU via the drivingcircuits
•Relayisusedcontrol the water pump
.

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3.4. RF Encoder & Decoder:
• The HT 12E Encoder ICs are series of CMOS LSIs for Remote Control
system applications. They are capable of Encoding 12 bit of
information which consists of N address bits and 12-N data bits.
• The HT 12D ICs are series of CMOS LSIs for remote control system
applications.
• This ICs are paired with each other. For proper operation a pair of
encoder/decoder with the same number of address and data format
should be selected.
• The Decoder receive the serial address and data from its
corresponding decoder, transmitted by a carrier using an RF
transmission medium and gives output to the output pins after
processing the data.
RF remote control:
• The circuit uses HT 12E, HT 12D encoder and decoder.
• 433MHz ASK transmitter and receiver is used for the
remote control.

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3. Block diagram of fire fighting robot
Receiver:

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4.Designing the robot
Circuit Design:
The major components in the above circuit diagram are at89c51 microcontroller and motor driver.
Here the motor driver input pins IN1, IN2 are connected to the P3.0 and P3.1 respectively to
control the motor directions. DC motor is connected to output terminals of L293D. EN1 pin is
connected to the 5V DC to drive the motor. Switches are connected to the P2.0 and P2.1 in pull
down configuration. First switch rotates the motor in clockwise direction and second switch rotates
the motor in clockwise direction and second switch rotates the motor in anti clockwise direction.
8th pin of motor driver is connected to the battery directly
RF TRANSMITTERAND RF RECEIVER:
Wireless Communicationusing RF Moduleand Interfacing with
8051 Microcontroller
Wireless communication is the transfer of information between two or more points that are not connected
by an electrical conductor. In this paper we discuss wireless communication using RF module and
interfaction RF with 8051microcontroller. An RF module (radio frequency module) is a small electronic
device used to transmit and/or receive radio signals between two devices. This wireless communication
may be accomplished through through radio frequency (RF) communication. RF communications
incorporate a transmitter or receiver which when interfaced with 8051 microcontrollers provides us with
various controlled operations. Keywords: Wireless communication, Rf module, RF transmitter, RF reciever,
8051 microcontroller, interfacing, controlled operation.

73
The RF module, as the name suggests, operates at Radio Frequency. The corresponding
frequency range varies between 30 kHz & 300 GHz. In this RF system, the digital data is
represented as variations in the amplitude of carrier wave. This kind of modulation is
known amplitude shift keying modulation. This RF module comprises of an RF Transmitter
and an RF Receiver. The transmitter/receiver (Tx/Rx) pair operates at a frequency of 434
MHz. An RF transmitter receives serial data and transmits it wirelessly through RF through
its antenna connected at pin4. The transmission occurs at the rate of 1Kbps - 10Kbps.The
transmitted data is received by an RF receiver operating at the same frequency as that of
the transmitter. The RF module is often used along with a pair of encoder/decoder. The
encoder is used for encoding parallel data for transmission feed while reception is decoded
by a decoder. HT12E-HT12D, HT640-HT648, etc. are some commonly used
encoder/decoder pair Ics

74
RF transmitter receives serial data and transmits to the receiver through an antenna which
is connected to the 4th pin of the transmitter. When logic 0 applied to transmitter then
there is no power supply in transmitter. When logic 1 is applied to transmitter then
transmitter is ON and there is a high power supply in the rangeof 4.5mA with 3V voltage
supply HT12EEncoder IC will convertthe 4 bit parallel data given to pins D0 – D3 to serial
data and will be available at DOUT. This output serial data is given to ASK RF Transmitter.
Address inputs A0 – A7 can be used to providedata security and can be connected to GND
(Logic ZERO) or left open (Logic ONE). Status of these Address pins should match with status
of address pins in the receiver for the transmission of the data. Data will be transmitted
only when the TransmitEnable pin (TE) is LOW. 1.1MΩ resistor willprovidethe necessary
external resistancefor the operation of the internal oscillator of HT12E.
ASK RF Receiver receives the data transmitted using ASK RF Transmitter. HT12D decoder
will convert the received serial data to 4 bits parallel data D0 – D3. The status of these
address pins A0-A7 should match with status of address pin in the HT12E at the transmitter
for the transmission of data. The LED connected to the above circuit glows when valid data
transmission occurs from transmitter to receiver. 51KΩ resistor will provide the necessary
resistance required for the internal oscillator of the HT12D.

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Operation of motor driver:
 L293D has 2 set of arrangements whereoneset has input 1, input 2, output 1 and
output 2 and other set has input 3, input 4, output 3 and output 4, according to block
diagramif pin no 2 & 7 arehigh then pin no 3 & 6 are also high
 If enable 1 and pin number 2 are high leaving pin number 7 as low then the motor
rotates in forward direction
 If enable 1 and pin number 2 are low leaving pin number 7 as high then the motor
rotates in reversedirection

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5. Circuit diagram of fire fighting robot:
Interfacing DC Motor with 8051 Microcontroller
When we talk about controlling the robot, the first thing comes into the mind is
controlling DC motors. Interfacing DC motor to the microcontrolleris very important
conceptin Robotic applications. By interfacing DC motor to the microcontroller,we
can do many things like controlling the direction of the motor, controlling the speed
of the motor. This article describes youhow to control the DC motor using AT89C51
controller.
CircuitPrinciple:
The maximum output current of microcontrollerpin is 15mA at 5V. But the power
requirements of most of DC motors is out of reach of the microcontrollerand even
the back emf (electro motive force)which is produced by the motor may damage the
microcontroller.Hence it is not good to interface DC motor directly to the controller.
So, use motordriver circuit in between of DC motor and controller.

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Operation principle:
With the developmentin the field of robotics,human intrusion has become lessand
robots are being widely used for safety purpose.In our day-to-day life, fire accidents
have becomecommonand sometimes may lead to hazards that make it hard for the
firemento protect human life. In such cases, a fire fighting robotis used to guard
human lives, wealth, and surroundings from the fire accidents.This fire fighting
robot projectis an advanced project for engineering students, who are interested in
robotics.This project project incorporates RF technologyfor remote operation and
also uses 8051 microcontroller.A fire fighting robot is capable of detecting fire if a
house catches fire while someone inthe house is either sleeping or not presentin
the house. By means of this fire fighting robot, people and properties can be saved
from fire accident.
MOTOR DRIVER:
 Provides an interface between the 5V logic signal from the microcontroller & the high
current / high voltage power side to drive the motor.
 Motor is an electromechanical device, which convert electrical energy to rotation/
mechanical energy.
 DC Geared Motor is used to drive the robotic vehicle.
RELAY & DRIVER CIRCUIT:
 Interfacing is required for connecting a relay with any microcontroller.
 Relays are inductive loads and controlwater pumps.
 Driving circuit is fixed between relays and processorpins.
 The output of the microcontroller is fed to the relay driver for current boosting. The output
of this magnetizes the relay.

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6. Working Principle of Fire Fighting Robot
There are several possibilities of fire in any remote area or in an industry. For instance, in
garments godowns, cotton mills, and fuel storage tanks, electric leakages may result in immense
fire & harm. In the worst of cases & scenarios, fire causes heavy losses both financially and by
taking lives. Robotics is the best possible way to guard human lives, wealth and surroundings. A
Firefighting robot is designed and built with an embedded system. It is capable of navigating alone
on a modeled floor while actively scanning the flames of fire. The robot could be used as a path
guide in a fireplace device or, in normal case, as an emergency device. This robot is designed in
such a way that it searches a fire, & douses it before the fire could spread out of range & control.
This type of firefighting robot will sooneror later work with firefighters,thus greatly
reducing the danger of injury to victims. Apart from this, this Firefighting robotic
projectwill also help generate interest along with the innovations in the field of
robotics while operating towards a sensible and obtainable solution to save lives and
mitigate the danger to property.
Working of project:
 The project uses HT12E Encoder which converts 4 bits data to serial output
which is then fed to the RF module for transmitting the same to be
received by the receiver RF module the output of which is fed to HT12D
the serial decoder IC, the output of which is fed to microcontroller
 The transmitting end MC is connected to a set of push button. Thus, while
a particular button is pressed the program executed delivers
corresponding 4-bit data which are then transmitted serially at port 1.
 The data so received at the receiver end of port 1 operates the motor
through motor driver IC L293D as required being interfaced from the
Microcontroller output port 2.
 The transmitter is powered by a 6v battery in series with a silicon diode to
finally develop required voltage for microcontroller circuit.
 The receiver is powered by a 12v battery in series with a silicon diode to
protect the circuits from accidental reverse battery connection.
 5V DC out of the 12V available from regulator IC 7805 is fed to the
controller, decoder, the motor driver IC L293D pin 8 for operation of the
motor.
 The receiving unit uses one more motor driver IC L293D for driving one
DC Motor for arm operation with a boom mounted on its shaft.

79
 At the end of the shaft a nozzle is connected to a water tanks mounted
water pump which is powered from “NO” contacts of a relay that is driven
by transistor Q1 from the output of MC pin 15, thus in the event of a fire the
robotic vehicle is moved over to the location by operating the left, right,
forward & backward button etc.
 After it reaches the site the nozzle mounted motor takes position through
the water on the fire from the water tank mounted DC pump actuated by the
relay RL1.
 Thus, the fire can be extinguished.
WORKING
The robot is a moving vehicle remotely controlled by one transmitting unit and a
receiving
unit for its moment. In this we used HT12E encoder which converts 4 bits data
to serial output. As explained above this is then fed to the RF module for
transmitting the same to be received by the receiver. The RF module the output
is fed to HT12D the serial decoder IC, the output of which is fed to
microcontroller pin 1 to 4. The transmitting end microcontroller is connected to
a set of pushbutton switches to its port 3 of 20 pin microcontroller AT89C2051.
Thus, while a particular button is pressed the program is executed to deliver
corresponding 4-bit data which are then transmitted serially at port 1 as
explained above. The data so received at the receiver end of port 1 of the
Microcontroller. A laser light is driven by transistor Q1 from the output of
microcontroller pin 15, while the robotic vehicle is manourved to the location by
operating the left, right, forward and backward button etc. after it reaches the
site the laser mounted on it takes position to throw the beam by operating
specific action button.

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III. RESULT
1. Applications:
 Industries are using RF solutions:
For monitoring, control, process, inventory tracking, data links and bar code reading
devices.
 Consumer products:
Electronic toys, home security, gate and garage door openers, intercom, fire and
safety systems, and irrigation controllers.
 Medical products:
Patient call and monitoring, handicap assistancedevice, surgery communication
system, remote patient data logging and ECG monitor.
 Can be used in server rooms for immediate action in case of fire.
 Can be used in extinguishing fire whereprobability of explosion is high. For e.g. Hotel
kitchens, LPG/CNG gas stores, etc.
-At power plant control rooms.
-At captain bridges.
-At flight control centers.
 The main purposeis to rescue the people by extinguishing fire in a building.
Industries areusing RF solutions for monitoring, control, process, inventory tracking,
data links and bar code reading devices.

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2. Advantage and Disadvantages:
Advantages:
Capability of sensing accurately with increased flexibility
materials.
Disadvantages:
Communication devices mostly use similar frequency, so interference occurs if the
address is not specified.
3.Future Scope:
fires and take appropriate action, without any human intervention.
had to do but were inherently life threatening.
-fighting is an obvious candidate for such automation.
can be enhanced by interfacing it with a wireless camera so that the person
controlling it can view the operation of the robot remotely on a screen.

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4.Conclusions:
Through this we can conclude that a robot can be usedin place of humans reducing
the risk of life of the firefighters. We can use them in our homes, labs, offices etc.
They provide us greater efficiency to detect the flame and it can be extinguish
before it become uncontrollable and threat to life. Hence, this robot can play a
crucial role.
This Project presents a Fire Fighting Robot Vehicle using RF communication, and it
designed and implemented MCU in embedded system domain.
achieved using the embedded
system.
industrial purpose.

83
5.References:
 DavidR. Shircliff, Builda Remote-Controlled Robot, TMH.
 www.atmel.in/devices/ATMEGA16.aspx.
 http://www.engineersgarage.com/electroniccomponents/rf-module-transmitter-receiver
 Kirk Zurell, C Programming for EmbeddedSystems, R&D Books.
 Raj Kamal, Embedded Systems, 2ndEdition, TMH.
 Intelligent Springer Handbook of Robotics Mini-Robot System InternationalJournal
of Computers,
Communications & Control, Vol. I, Issue21, January 2013 by Bruno Siciliano.
 Robot mechanism and mechanical devices ----PaulE Sandin
 Mechanisms and Robots Analysis with MAT ----Den b. Marghetu
 Development and Applications of Automatic Fire Fighting Robot International Journal
of Advanced Research in Computer Engineering & Technology (IJARCET)Vol. 2, Issue
14, August2013.
 Implementing a FireFighting Robot as an Effective Sensors by Prof. Bong D.M.K.
 Design & Implement of Automatic Fire Fighting Robot by Prof. Paule Thomas
 “Effectiveness of Thermostat Sensor” Extinguisher Security InternationalConference
(WSS), 2012.

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Fire fighting final report