Object Follower Bot

Project Report Submitted in Partial Fulfillment of the Requirement for

The Project Of Mechatronics

in

Mechanical Engg. of

Aiktc , New Panvel

By

13ME80 KHAN FAHAD

13ME106 SEIKH FARHAN

13ME107 MUKADAM SHAFIQUE

14DME UMAR ANSARI

DECLARATION

We, Khan Fahad, seikh farhan, Mukadam Shafique and Umar Ansari the

students of T.e M.e 2 , hereby declare that the work presented in this Minor

Project is an authentic record of our own and has been carried out taking care of

Engineering Ethics under the guidance of Prof. Arshad qureshi

Khan Fahad (13me80) ………………………

Seikh Farhan (13me106) ………………………

Mukadam Shafique (13me107) ………………………

Umar Ansari (14dme) ………………………

ii

CERTIFICATE

This is to certify that the work embodied in this Minor Project entitled

“Object follower Robot” has been satisfactorily completed by the students of third

year, Mr Khan fahad , Mr. Seikh Farhan , Mr. Mukadam Shafique And Mr. Umar

Ansari . The work was carried out satisfactorily under the supervision and

guidance of the undersigned in the Department of Mechanical Engineering, Aiktc

, New Panvel for the partial fulfillment of the requirement of degree of Bachelor

of Engineering during the Academic year 2015-2016.

Prof. Arshad Qureshi

Professor and Project Guide,

Mechanical Department

Approved

Prof. Zakir Ansari Dr. Abdul Razzak

Head of Department Director

iii

ACKNOWLEDGEMENT

CONTENTS

DECLARATION … ii

CERTIFICATE … iii

1. INTRODUCTION … 01

2. REWVIEW OF LITERATURE … 05

2.1 Construction … 07

2.1.1 Hardware Unit … 07

2.1.2 Software Unit … 13

2.2 Basic Parts Of Project …29

2.2.1 Sensors … 29

2.2.2 Microcontroller … 29

2.2.3 Driver … 30

2.2.4 Motors … 30

2.3 Problem Faced In Making Project … 31

2.4 Testing … 32

2.5 Applications … 33

2.6 Future Scope By Improvement … 33

3. COMPONENTS … 34

3.1 Microcontroller ATMEGA8L … 35

3.2 IC L293D … 36

3.3 IC LM324N … 37

3.4 IC 7805 … 38

3.5 Resistor … 38

3.6 IR LED … 39

3.7 Photodiode … 40

4. RESULTS … 41

5. REFERENCES ... 42

6. APPENDICES … 43

6.1 Datasheet … 43

6.2 Program …48

LIST OF FIGURS

Figure 2.1 Block Diagram of Project ... 06

Figure 2.2 IR Sensor circuit ... 10

Figure 2.3 Controller Circuit ... 12

Figure 2.4 PCB layout of sensor …18

Figure 2.5 PCB of Controller Circuit ... 19

Figure 2.6 Final PCB Layout ... 20

Figure 3.1 Microcontroller ATMEGA8L ... 35

Figure 3.2 IC L293D ... 36

Figure 3.3 IC LM324N … 37

Figure 3.4 IC 7805 … 38

Figure 3.5 Resistor … 39

Figure 3.6 IR LED … 39

Figure 3.7 Photodiode … 40

Figure 6.1 ATMEGA8L Pin Diagram … 45

Figure 6.2 IC 7805 Pin Diagram … 46

Figure 6.3 IC LM324N Pin Diagram … 47

Figure 6.4 IC 293 Pin Diagram … 48

1. INTRODUCTION

Robotics is part of Today’s communication. In today’s world

ROBOTICS is fast growing and interesting field. It is simplest way for latest

technology modification. Now a day’s communication is part of advancement of

technology, so we decided to work on robotics field, and design something which

will make human life simpler in day today aspect. Thus we are supporting this

cause.

Robotics is the branch of technology that deals with the design,

construction, operation, structural disposition, manufacture and application of

robots and computer systems for their control, sensory feedback, and information

processing.

Obstacle detection and avoidance robots are intelligent robots which

can perform desired tasks in unstructured environments by finding and

overcoming obstacles in their way without continuous human guidance.

In robotics, obstacle avoidance is the task of satisfying some control

objective subject to non-intersection or non-collision position constraints.

Normally obstacle avoidance is considered to be distinct from path planning in

that one is usually implemented as a reactive control law while the other involves

the pre-computation of an obstacle-free path which a controller will then guide a

robot along. A practical real-time system for passive obstacle detection and

avoidance is presented.

Robot Sensors are essential components in creating autonomous robots

as they are the only means for a robot to detect information about itself and its

environment. As little as one sensor is needed by a robot, though increasing the

number and variety of sensors tends to increase the robot’s ability to get a more

thorough understanding of the world around it.

There are a wide variety of sensors available which are capable of

measuring almost anything, from environmental conditions (distance, light,

sound, temperature) to angular and linear acceleration, forces and distances. The

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first sensor often incorporated into a mobile robot is a distance sensor, which is

usually in the form of an infrared or ultrasonic sensor. In both cases, a pulse (of

light or sound) is sent and its reflection is timed to get a sense of distance. Usually

these values are sent to the controller many times each second.

Robot Shop offers a wide variety of sensors applicable to almost any

robotics project. If you are looking for a distance sensor, we offer them in a

variety of configurations and optimal distances to suit almost any budget. If you

are looking for a more professional solution for measuring distances, take a look

at our selection of scanning laser rangefinders, which are able to scan over >180

degrees (and less than 1 degree of accuracy) in well under 1 second.IR Pair is

used as sensor to detect the presence of objects. IR LED is used for detecting

objects.

In this project mainly when ever robot senses any obstacle

automatically diverts its position to left or right and follows the path. Robot

consists of two motors, which control the side pair wheels of each and help in

moving forward and backward direction. Robot senses the object with help of

obstacle sensor. IR pair is used for detecting the obstacle. The two basic parts for

working with IR are the emitter and the detector. The emitter is typically an LED

that emits near-infrared light.

Infrared (IR) light is electromagnetic radiation with a wavelength

longer than that of visible light, measured from the nominal edge of visible red

light at 0.74 micrometers (µm), and extending conventionally to 300 µm. These

wavelengths correspond to a frequency range of approximately 1 to 400 THz, and

include most of the thermal radiation emitted by objects near room temperature.

Microscopically, IR light is typically emitted or absorbed by molecules when they

change their rotational-vibration movements.

Infrared light is used in industrial, scientific, and medical applications.

Night-vision devices using infrared illumination allow people or animals to be

observed without the observer being detected. In astronomy, imaging at infrared

wavelengths allows observation of objects obscured by interstellar dust. Infrared

02

Imaging cameras are used to detect heat loss in insulated systems, observe

changing blood flow in the skin, and overheating of electrical apparatus.

IR LED IR detectors are specially filtered for Infrared lighted are not

good at detecting visible light. On the other hand, photocells are good at detecting

yellow/green visible light, not well at IR light.

IR detectors have a demodulator inside that looks for modulated IR at

38 KHz. Just shining an IR LED won’t be detected, it has to be PWM blinking at

38KHz. Photocells do not have any sort of demodulator and can detect any

frequency (including DC) within the response speed of the photocell (which is

about 1KHz). IR detectors are digital out - either they detect 38KHz IR signal

and output low (0V) or they do not detect any and output high (5V). Photocells

act like resistors, the resistance changes depending on how much light they are

exposed to.

A photodiode is a type of photo detector capable of converting light

into either current or voltage, depending upon the mode of operation. The

common, traditional solar cell used to generate electric solar power is a large area

photodiode.

Photodiodes are similar to regular semiconductor diodes except that

they may be either exposed (to detect vacuum UV or X-rays) or packaged with a

window or optical fiber connection to allow light to reach the sensitive part of the

device. Many diodes designed for use specifically as a photodiode use a PIN

junction rather than a p-n junction, to increase the speed of response. A

photodiode is designed to operate in reverse bias. In this project we develop a

robot such that it will be moving according to path assigned to it if at all there is

any obstacle in between then the robot stops and change its direction. This sort of

project is very much useful in the industries where the automated supervision is

required.

This project is basic stage of any automatic robot. This robot has

sufficient intelligence to cover the maximum area of provided space. It has a

infrared sensor which are used to sense the object coming in between the path of

robot. It will move in a particular direction and Follow the Object which is

coming in its path.

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A robot object follower system comprising: a robot housing which

navigates with respect to a surface; a sensor subsystem having a defined

relationship with respect to the housing and aimed at the surface for detecting the

surface, the sensor subsystem including: an optical emitter which emits a directed

beam having a defined field of emission, and a photon detector having a defined

field of view which intersects the field of emission of the emitter at a finite

region; and a circuit in communication with the detector for redirecting the robot

when the surface does not occupy the region to avoid follow object.

Object sensors are nothing but the IR pair. As the transmitter part

travel IR rays from to receiver here also transmitter send the data receiver but

these IR pair are places beside each other. So whenever an object sensor got a

obstacle in between its way the IR rays reflects in a certain angle. As they are

placed side by each.

We have used two D.C motors to give motion to the robot. The

construction of the robot circuit is easy and small .The electronics parts used in

the robot circuits are easily available and cheap too.

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2. REVIEW OF LITERATURES

This robot has sufficient intelligence to cover the maximum area of

provided space. It has an infrared sensor which is used to sense the obstacles

coming in between the path of robot. It will move in a particular direction and

avoid the obstacle which is coming in its path.

It uses IR (Infra Red) sensors and two IR transmitting circuitry. When

the obstacle comes in path of robot IR beam is reflected from the obstacle then

sensor gives zero voltage to µc. This zero voltage is detected then µc decides to

avoid the obstacle by taking left or right turn. If the sensor gives +5v to µc that

means there is no obstacle present in its path so it goes straight until any obstacle

is detected.

The two IR transmitter circuits are fitted on front and left side of

robot. The two IR sensors are placed near to transmitters’ IR LEDs. The

connections can be given from main circuit to sensors using simple twisted pair

cables. Two motors namely right motor and left motor are connected to driver IC

(L293D). L293D is interface with µc. Micro-controller sends logic 0 & logic 1 as

per the programming to driver IC which moves motors forward or reverse

direction. Now let us see all the things in our project.

05

Figure 2.1: Block Diagram of Project

06

2.1 Construction

The project is combination of different units as follows:

1. Hardware

2. Software

2.1.1 Hardware Unit

The hardware part includes the structure of robot that is Electronics and

Communication structure, PCB (printed circuit board), blower, and battery. In this

unit all the connections are being made along with the PCB now let us see in brief

how it can be done.

2.1.1.1 Electronics and Communication Connection

In Electronics and Communication connection wheel is connected to base very

tightly to avoid errors in the system. Connection of blower is made with lower

part of base and battery is connected in upper portion of base for power supply to

the system which is very important battery used here is of 6v battery, blower of

+5V to +9V. And along with wheel electrical motors are connected with base

having r.p.m of 100 rpm.

2.1.1.2 PCB Connection

A printed circuit board, or PCB, is used to Electronics and Communicationly

support and electrically connect electronic components using conductive pathways,

tracks or signal traces etched from copper sheets laminated onto a non-conductive

substrate.

The PCB is printed circuit board having circuit made with cooper

layer on the plate there are various steps to design a PCB for that the basic thing

required is circuit. So, the circuits required for the system are:

07

2.1.1.2.1 IR Sensor Circuit

An infrared sensor is an electronic device that emits and/or detects infrared

radiation in order to sense some aspect of its surroundings. Infrared sensors can

measure the heat of an object, as well as detect motion. Many of these types of

sensors only measure infrared radiation, rather than emitting it, and thus are

known as passive infrared (PIR) sensors.

All objects emit some form of thermal radiation, usually in the infrared

spectrum. This radiation is invisible to our eyes, but can be detected by an

infrared sensor that accepts and interprets it. In a typical infrared sensor like a

motion detector, radiation enters the front and reaches the sensor itself at the center

of the device. This part may be composed of more than one individual sensor,

each of them being made from piezoelectric materials, whether natural or

artificial.

IR Sensor includes photodiode and IR LED which play the role of

receiver and transmitter respectively.

2.1.1.2.1.1 IR LED

An IR LED, also known as IR transmitter, is a special purpose LED that transmits

infrared rays in the range of 760 nm wavelength. Such LEDs are usually made of

gallium arsenide or aluminum gallium arsenide. They, along with IR receivers,

are commonly used as sensors.

The appearance is same as a common LED. Since the human eye

cannot see the infrared radiations, it is not possible for a person to identify

whether the IR LED is working or not, unlike a common LED. To overcome this

problem, the camera on a cell phone can be used. The camera can show us the IR

rays being emanated from the IR LED in a circuit.

08

2.1.1.2.1.2 Photodiode

A photodiode is a type of photo detector capable of converting light into either

current or voltage, depending upon the mode of operation. The common,

traditional solar cell used to generate electric solar power is a large area

photodiode. It is use to sense the reflected IR rays which reflect due to presence of

obstacle and due to it robot change its path.

This sensor uses IR (Infra Red) sensors and two IR transmitting

circuitry. When the obstacle comes in path of robot IR beam is reflected from the

obstacle then sensor gives zero voltage to µc. This zero voltage is detected then

µc decides to avoid the obstacle by taking left or right turn. If the sensor gives

+5v to µc that means there is no obstacle present in its path so it goes straight

until any obstacle is detected. The sensor circuit is shown in figure 2.2.

It uses IR (Infra Red) sensors and two IR transmitting circuitry. When

the obstacle comes in path of robot IR beam is reflected from the obstacle then

sensor gives zero voltage to µc. This zero voltage is detected then µc decides to

avoid the obstacle by taking left or right turn. If the sensor gives +5v to µc that

means there is no obstacle present in its path so it goes straight until any obstacle

is detected.

The two IR transmitter circuits are fitted on front and left side of

robot. The two IR sensors are placed near to transmitters’ IR LEDs. The

connections can be given from main circuit to sensors using simple twisted pair

cables.

09

Figure 2.2: IR Sensor circuit

10

After having the circuit it is easy to design PCB. Circuit is traced in PCB by using

different software here we have used PCB Express software to design layout then

it is etched and further the component are soled in it.

2.1.1.2.2 Controller Circuit

A microcontroller (sometimes abbreviated µC, uC or MCU) is a small computer

on a single integrated circuit containing a processor core, memory, and

programmable input/output peripherals.

Microcontrollers are used in automatically controlled products and

devices, such as automobile engine control systems, implantable medical devices,

remote controls, office machines, appliances, power tools, toys and other

embedded systems. By reducing the size and cost compared to a design that uses a

separate microprocessor, memory, and input/output devices, microcontrollers

make it economical to digitally control even more devices and processes. Mixed

signal microcontrollers are common, integrating analog components needed to

control non-digital electronic systems.

Here we are giving code to Microcontroller according to those codes

our robot move; these codes are created by programming logic in Keil software

and latter burn in microcontroller by flash magic software. These codes control

the motor by the logic of 0 and by logic 1 and through this direction of robot is

control.

But for the purpose of providing this logic to motor we use an IC that

is L293D Having 16 pin it get input by output of microcontroller this make robot

an intelligent or autonomous robot this IC also amplifies the current and provide

to motor .

11

Figure 2.3: Controller Circuit

12

After having the circuit it is easy to design PCB. Circuit is traced in PCB by using

different software here we have used PCBExpress software to design layout then

it is etched and further the component are solded in it.

Now when all the PCBs are connected according to required condition

and the electro-Electronics and Communication structure is ready still the system

will not work without software unit.

Let us discuss the software unit.

2.1.2 Software Unit

Computer software or just software is a collection of computer programs and

related data that provides the instructions for telling a computer what to do and

how to do it. Software refers to one or more computer programs and data held in

the storage of the computer for some purposes. In other words, software is a set of

programs, procedures, algorithms and its documentation concerned with the

operation of a data processing system. Program software performs the function of

the program it implements, either by directly providing instructions to the

computer hardware or by serving as input to another piece of software.

The term was coined to contrast to the old term hardware (meaning

physical devices). In contrast to hardware, software "cannot be touched".

Software is also sometimes used in a more narrow sense, meaning application

software only. Sometimes the term includes data that has not traditionally been

associated with computers, such as film, tapes, and records.

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2.2 Basic Parts Of Project

So, now we may say that there are following main parts are there used

in our projects those are:

2.2.1 Sensors

A sensor (also called detector) is a converter that measures a physical

quantity and converts it into a signal which can be read by an observer or by an

(today mostly electronic) instrument.

Sensors are used in everyday objects such as touch-sensitive elevator

buttons (tactile sensor) and lamps which dim or brighten by touching the base.

There are also innumerable applications for sensors of which most people are

never aware. Applications include cars, machines, aerospace, medicine ,

manufacturing and robotics.

The IR Transmitter block mainly used to generate IR signal. It uses

timer IC555 in astable multivibrator mode to generate square wave which have

continuous pulses of 50% duty cycle of frequency 38 KHz. This transmitter is so

arranged that the IR rays are focused on the sensor.

2.2.2 Microcontroller

This is the most important block of the system. Microcontroller is the

decision making logical device which has its own memory, I/O ports, CPU and

Clock circuit embedded on a single chip.

A microcontroller (sometimes abbreviated µC, uC or MCU) is a small

computer on a single integrated circuit containing a processor core, memory, and

programmable input/output peripherals. Program memory in the form of NOR

flash or OTP ROM is also often included on chip, as well as a typically small

amount of RAM. Microcontrollers are designed for embedded applications, in

contrast to the microprocessors used in personal computers or other general

purpose applications.

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Microcontrollers are used in automatically controlled products and

devices, such as automobile engine control systems, implantable medical devices,

remote controls, office machines, appliances, power tools, toys and other

embedded systems.

By reducing the size and cost compared to a design that uses a separate

microprocessor, memory, and input/output devices, microcontrollers make it

economical to digitally control even more devices and processes. Mixed signal

microcontrollers are common, integrating analog components needed to control

non-digital electronic systems

2.2.3 Driver

L293D is used as driver IC. Motors are connected to this IC. According to

program in µc it drives the left and right motor. L293D is a dual H-bridge motor

driver integrated circuit (IC). Motor drivers act as current amplifiers since they

take a low-current control signal and provide a higher-current signal. This higher

current signal 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. The motor operations of two motors can be controlled by

input logic at pins 2 & 7 and 10 & 15. Input logic 00 or 11 will stop the

corresponding motor. Logic 01 and 10 will rotate it in clockwise and

anticlockwise directions, respectively.

Enable pins 1 and 9 (corresponding to the two motors) must be high

for motors to start operating. When an enable input is high, the associated driver

gets enabled. As a result, the outputs become active and work in phase with their

inputs. Similarly, when the enable input is low, that driver is disabled, and their

outputs are off and in the high- impedance state.

2.2.4 Motors

An electric motor is an electromechanical device that converts electrical energy

into mechanical energy.

30

Most electric motors operate through the interaction of magnetic fields

and current-carrying conductors to generate force.

The reverse process, producing electrical energy from mechanical

energy, is done by generators such as an alternator or a dynamo; some electric

motors can also be used as generators, for example, a traction motor on a vehicle

may perform both tasks. Electric motors and generators are commonly referred to

as electric machines.

2.3 Problem Faced In Making Project

Although the concept & design of the project seemed perfect, there were

some problems faced while actual implementation:

2.3.1 Proving Proper Power to different circuit

Solution: taking high precaution in designing of circuit.

2.4 Testing

There is always necessary to check the work for that here we have

implemented various test for following:

2.4.1 Continuity test

First of all we checked the PCB that all the tracks are as per the design

of PCB and showing continuity with the help of multimeter and PCB layout.

2.4.2 Short circuit test

Then we checked the PCB for any unwanted short circuits with the

help of multimeter and PCB layout.

2.4.3 Soldering

In the next step, we soldered the required components. And then

checked that there are no any unwanted shorts occurred due to soldering without

putting IC's and keeping power supply off.

2.4.4 Power supply test

In the next step, we put power supply on and checked whether

required voltage is appearing at the required voltage is appearing at the required

points i.e.+Vcc and GND at the respective points. We took care of not connecting

IC's in the circuit while performing this test.

2.4.5 Microcontroller test

For testing the microcontroller, we wrote the square wave generation

program for generating square wave on each port pin. Then we fed the program in

microcontroller and checked the output with the help of CRO by connecting the

microcontroller in the circuit. We took care of not connecting any other IC in the

circuit.

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2.5 Applications

There are following application of Object Follower robot

1) This logic has been specially designed for _______ . By using heavy rating

motors, strong mechanical structure and using highly sensitive obstacle sensors, it

efficiently works as________.

2) Just by making small changes in software this system can be used for avoiding

concealed paths. This robot can effectively sense the obstacles and find out

correct path.

3) With proper programming we can use it as a______.

4) In Mines.

2.6 Future Scope By Improvement

The future uses of IR obstacle detector are as follows:

2.6.1 Adding a Camera:

If the current project is interfaced with a camera (e.g. a Webcam) robot

can be driven beyond line-of-sight & range becomes practically unlimited as

networks have a very large range.

2.6.2 Use as a fire fighting robot:

By adding temperature sensor, water tank and making some changes in

programming we can use this robot as fire fighting robot.

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3. COMPONENTS

An electronic component is a basic electronic element that is available in a

discrete form (a discrete device or discrete component) that has two or more

electrical terminals (or leads). These leads connect, usually soldered to a printed

circuit board, to create an electronic circuit (a discrete circuit) with a particular

function (for example an amplifier, radio receiver, or oscillator). Basic electronic

components may be packaged discretely, as arrays or networks of like

components, or integrated inside of packages such as semiconductor integrated

circuits, hybrid integrated circuits, or thick film devices. The following list of

electronic components focuses on the discrete version of these components,

treating such packages as components in their own right.

So the components used in our project are:

1. Microcontroller ATMEGA8L

2. IC 293D

3. IC LM324N

4. IC 7805

5. Potentiometer 20k

6. Resistor 1k ohm

7. IR LED

8. Photo diode

9. Battery

10. Soldering wire

Let us discuss all components in brief

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3.1. Microcontroller ATMEGA8L

The ATmega8 is a low-power CMOS 8-bit microcontroller based on the AVR

RISC architecture. By executing powerful instructions in a single clock cycle, the

ATmega8 achieves throughputs approaching 1 MIPS per MHz, allowing the

system designer to optimize power consumption versus processing speed.

Fig 3.1 Microcontroller ATMEGA8L

ATMEGA8L Features:

High-performance, Low-power AVR® 8-bit Microcontroller Advanced RISC

Architecture

– 130 Powerful Instructions – Most Single-clock Cycle Execution

– 32 x 8 General Purpose Working Registers

– Fully Static Operation

Nonvolatile Program and Data Memories

– 8K Bytes of In-System Self-Programmable Flash

In-System Programming by On-chip Boot Program

Special Microcontroller Features

– Power-on Reset and Programmable Brown-out Detection

– Internal Calibrated RC Oscillator

– External and Internal Interrupt Sources

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I/O and Packages

– 23 Programmable I/O Lines

– 28-lead PDIP, 32-lead TQFP, and 32-pad MLF

Operating Voltages 2.7 - 5.5V (ATmega8L)

3.2 IC L293D

L293D is a dual H-bridge motor driver integrated circuit (IC). Motor drivers act

as current amplifiers since they take a low-current control signal and provide a

higher-current signal. This higher current signal is used to drive the motors.

Fig 3.2 IC L293D

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. The motor operations of two motors can be controlled by

input logic at pins 2 & 7 and 10 & 15. Input logic 00 or 11 will stop the

corresponding motor. Logic 01 and 10 will rotate it in clockwise and

anticlockwise directions, respectively. Enable pins 1 and 9 (corresponding to

36

the two motors) must be high for motors to start operating. When an enable

input is high, the associated driver gets enabled.

As a result, the outputs become active and work in phase with

their inputs. Similarly, when the enable input is low, that driver is disabled, and

their outputs are off and in the high-impedance state.

3.3 IC LM324N

LM324 is a 14pin IC consisting of four independent operational amplifiers (op-

amps) compensated in a single package. Op-amps are high gain electronic voltage

amplifier with differential input and, usually, a single-ended output. The output

voltage is many times higher than the voltage difference between input terminals

of an op-amp.

Fig 3.3 IC LM324N

These op-amps are operated by a single power supply LM324 and need

for a dual supply is eliminated. They can be used as amplifiers, comparators,

oscillators, rectifiers etc. The conventional op-amp applications can be more

easily implemented with LM324.

37

3.4 IC 7805

Fixed voltage Positive and Negative regulator ICs are used in circuits to give

precise regulated voltage.78 XX series regulator IC can handle maximum 1

ampere current. The Regulator ICs require minimum 1.5 higher input voltage than

their voltage rating. For example 7805 IC requires minimum 6.5 volts to give 5

volt output. Here are some circuit designs of IC 7805 to monitor the output

voltage.

Fig 3.4 IC 7805

3.5 Resistor

A resistor is a passive two-terminal electrical component that implements

electrical resistance as a circuit element. The current through a resistor is in direct

proportion to the voltage across the resistor's terminals. Thus, the ratio of the

voltage applied across a resistor's terminals to the intensity of current through the

circuit is called resistance.

V= IR

where I is the current through the conductor in units of amperes, V is

the potential difference measured across the conductor in units of volts, and R is

the resistance of the conductor in units of ohms. More specifically, Ohm's law

states that the R in this relation is constant, independent of the current.

38

Resistors are common elements of electrical networks and electronic

circuits and are ubiquitous in electronic equipment. Practical resistors can be

made of various compounds and films, as well as resistance wire (wire made of a

high-resistivity alloy, such as nickel-chrome). Resistors are also implemented

within integrated circuits, particularly analog devices, and can also be integrated

into hybrid and printed circuits.

Fig 3.5 RESISTOR

3.6 IR LED

An IR LED, also known as IR transmitter, is a special purpose LED that transmits

infrared rays in the range of 760 nm wavelength. Such LEDs are usually made of

gallium arsenide or aluminum gallium arsenide. They, along with IR receivers,

are commonly used as sensors.

Fig 3.6 IR LED

39

The appearance is same as a common LED. Since the human eye

cannot see the infrared radiations, it is not possible for a person to identify

whether the IR LED is working or not, unlike a common LED. To overcome this

problem, the camera on a cell phone can be used. The camera can show us the IR

rays being emanated from the IR LED in a circuit.

3.7 Photodiode

A photodiode is a type of photo detector capable of converting light

into either current or voltage, depending upon the mode of operation. The

common, traditional solar cell used to generate electric solar power is a large area

photodiode.

Fig 3.7 Photodiode

Photodiodes are similar to regular semiconductor diodes except that they may be

either exposed (to detect vacuum UV or X-rays) or packaged with a window or

optical fiber connection to allow light to reach the sensitive part of the device.

Many diodes designed for use specifically as a photodiode use a PIN junction

rather than a p-n junction, to increase the speed of response. A photodiode is

designed to operate it.

40

4. RESULTS

Thus, we believe that our project will be beneficial for various purposes & hence

our efforts will be fruitful. So, we made a successfully obstacle detector robot

having application of vacuum cleaner which have ability to move freely anywhere

and along with it, it have ability to create its own path and it avoid obstacle by

artificial intelligence provided by programming in microcontroller to perform

action and IR sensor to sense the obstacle, it also clean the area where it move

with vacuum cleaner which is its application.

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5. REFERENCES

1. "Atmel’s Self-Programming Flash Microcontrollers" by Odd Jostein

Svendsli 2003

2. http://www.semico.com

3. Heath, Steve (2003). Embedded systems design. EDN series for design

engineers (2 ed.). Newnes. pp. 11–12. ISBN 9780750655460.

4. Easy Way to build a microcontroller project

5. Robert Edwards (1987). "Optimizing the Zilog Z8 Forth Microcontroller

for Rapid Prototyping". p. 3.

6. www.infineon.com/mcu

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6. APPENDICES

6.1 Datasheet

6.1.1 ATMEGA8L

6.1.2 IC 7805

6.1.3 IC LM324N

6.1.4 IC 293D

6.1.1 ATMEGA8L

1. Introduction

• High-performance, Low-power Atmel®AVR® 8-bit Microcontroller

• Advanced RISC Architecture

– 130 Powerful Instructions – Most Single-clock Cycle Execution

– 32 × 8 General Purpose Working Registers

– Fully Static Operation

– Up to 16MIPS Throughput at 16MHz

– On-chip 2-cycle Multiplier

• High Endurance Non-volatile Memory segments

– 8Kbytes of In-System Self-programmable Flash program memory

– 512Bytes EEPROM

– 1Kbyte Internal SRAM

– Write/Erase Cycles: 10,000 Flash/100,000 EEPROM

– Data retention: 20 years at 85°C/100 years at 25°C

– Optional Boot Code Section with Independent Lock Bits

2. In-System Programming by On-chip Boot Program

3. True Read-While-Write Operation

– Programming Lock for Software Security

• Peripheral Features

– Two 8-bit Timer/Counters with Separate Prescaler, one Compare Mode

– One 16-bit Timer/Counter with Separate Prescaler, Compare Mode, and

Capture

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2. Mode

– Real Time Counter with Separate Oscillator

– Three PWM Channels

– 8-channel ADC in TQFP and QFN/MLF package

3. Eight Channels 10-bit Accuracy

– 6-channel ADC in PDIP package

4. Six Channels 10-bit Accuracy

– Byte-oriented Two-wire Serial Interface

– Programmable Serial USART

– Master/Slave SPI Serial Interface

– Programmable Watchdog Timer with Separate On-chip Oscillator

– On-chip Analog Comparator

• Special Microcontroller Features

– Power-on Reset and Programmable Brown-out Detection

– Internal Calibrated RC Oscillator

– External and Internal Interrupt Sources

– Five Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down,

and

5. Standby

• I/O and Packages

– 23 Programmable I/O Lines

– 28-lead PDIP, 32-lead TQFP, and 32-pad QFN/MLF

• Operating Voltages

– 2.7V - 5.5V (ATmega8L)

– 4.5V - 5.5V (ATmega8)

• Speed Grades

– 0 - 8MHz (ATmega8L)

– 0 - 16MHz (ATmega8)

• Power Consumption at 4Mhz, 3V, 25°C

– Active: 3.6mA

– Idle Mode: 1.0mA

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6. 8-bit

7. with 8KBytes

8. In-System

9. Programmable

10. Flash

Fig 6.1 ATMEGA8L PIN DIAGRAM

6.1.2 IC 7805

1. Internal Thermal Overload Protection.

2. Internal Short Circuit Current Limiting.

3. Output Current up to 1.5A.

4. Satisfies IEC-65 Specification. (International Electronical Commission).

5. Package is TO

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Fig 6.2 IC 7805 PIN DIAGRAM

6.1.3 IC LM324N

• Internally frequency-compensated for unity gain

• Large DC voltage gain: 100dB

• Wide bandwidth (unity gain): 1MHz (temperature-compensated)

• Wide power supply range Single supply: 3VDC to 30VDC or dual

Supplies: ±1.5VDC to ±15VDC

• Very low supply current drain: essentially independent of supply

Voltage (1mW/op amp at +5VDC)

• Low input biasing current: 45nADC (temperature-compensated)

• Low input offset voltage: 2mVDC and offset current: 5nADC

• Differential input voltage range equal to the power supply voltage

• Large output voltage: 0VDC to VCC-1.5VDC swing

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Fig 6.3 LM324N PIN DIAGRAM

6.1.4 IC 293D

• Terminations: 100 % matte tin, standard, tin/lead available

• Compliant terminations

• Molded case available in six case codes

• Compatible with “High Volume” automatic pick and place equipment

• Optical character recognition qualified

• Meets IEC specification QC300801/US0001 and

EIA535BAAC mechanical and performance requirements

• Compliant to RoHS Directive 2002/95/EC

• Moisture sensitivity level 1

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Fig 6.4 IC 293 PIN DIAGRAM

6.2 Program

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