LINE FOLLOWING PICK AND PLACE

ROBOTA Project submitted in partial fulfillment of the requirements for

the award of the degree of

B.Tech

in

ELECTRONICS AND INSTRUMENTATION

By

YASH KUMAR YADAV (1009032059)

VINOD KUMAR (1009032058)

PRADEEP KUMAR (1009032037)

ELECTRONICS AND INSTRUMENTATION

IEC COLLEGE OF ENGINEERING & TECHNOLOGY

GREATER NOIDA

MAY 2014

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DECLARATION

We, hereby declare that this submission is our own work and that, to the best of our

knowledge and belief, it contains no material previously published or written by

another person nor material which to a substantial extent has been accepted for the

award of any other degree or diploma of the university or other institute of higher

learning, except where due acknowledgement has been made in the text.

1. Signature....................................................

Name YASH KUMAR YADAV

Roll No 1009032059

Date ...................................................

2. Signature....................................................

Name VINOD KUMAR

Roll No 1009032058

Date ...................................................

3. Signature...................................................

Name PRADEEP KUMAR

Roll No. 1009032037

Date ...................................................

MR.SATISH JAISWAL MR. R.P. SINGH

Guide Head of the Department

Project Viva-voce held on _____________________________

Internal Examiner External Examiner

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ABSTRACT

Mankind has always strived to give life like qualities to its artifacts in an attempt to

find substitutes for himself to carry out his orders and also to work in a hostile

environment. The popular concept of a robot is of a machine that looks and works like

a human being.

The industry is moving from current state of automation to Robotization, to increase

productivity and to deliver uniform quality. The industrial robots of today may not

look the least bit like a human being although all the research is directed to provide

more and more anthropomorphic and humanlike features and super-human

capabilities in these.

One type of robot commonly used in industry is a robotic manipulator or simply a

robotic arm. It is an open or closed kinematic chain of rigid links interconnected by

movable joints. In some configurations, links can be considered to correspond to

human anatomy as waist, upper arm and forearm with joint at shoulder and elbow. At

end of arm a wrist joint connects end effectors which may be a tool and its fixture or a

gripper or any other device to work.

Here how a pick and place Line following robot can be designed for a workstation

where loading and packing of lead batteries is been presented. All the various

problems and obstructions for the loading process has been deeply analyzed and been

taken into consideration while designing the pick and place line following robot.

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ACKNOWLEDGEMENT

It gives us a great sense of pleasure to present the report of the B. Tech Project

undertaken during. Tech. Final Year. We owe special debt of gratitude to Project In

charge Mr. Satish Jaiswal, Department of Electronics & Instrumentation

Engineering, IEC College of engineering & technology, Greater Noida for his

constant support and guidance throughout the course of our work. His sincerity,

thoroughness and perseverance have been a constant source of inspiration for us. It is

only his cognizant efforts that our endeavours have seen light of the day.

We also take the opportunity to acknowledge the contribution of Professor R.P.

Singh Head, Department of Electronics & Instrumentation Engineering, IEC College

of Engineering, Greater Noida for his full support and assistance during the

development of the project.

We also do not like to miss the opportunity to acknowledge the contribution of all

faculty members of the department for their kind assistance and cooperation during

the development of our project. Last but not the least, we acknowledge our friends for

their contribution in the completion of the project.

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TABLE OF CONTENTS

TITLE PAGE NO.

ABSTRACT

ACKNOWLEDGEMENT

TABLE OF CONTENT

LIST OF TABLE

LIST OF FIGURE

CHAPTER ONE

1.1INTRODUCTION TO LINE FOLLOWING ROBOT

1.2 TYPES OF ROBOT

1.3 AIM

1.4 OBJECTIVE

1.5 SCOPE

1.6 INTRODUCTION TO EMBEDDED SYSTEM

CHAPTER TWO

2.1 AT89C51 MICROCONTRILLE

2.2 HARDWARE COMPONENT EXPLANATION

2.3 BLOCK DIAGRAM

CHAPTER THREE

3.1WORKING PROCEDURE

CHAPTER FOUR

4.1SOFTWARE TOOLS

CONCLUSION AND FUTURE SCOPE

REFE

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LIST OF TABLE

TABLE 2.1 PORT 3 ALTERNATE FUCTION

TABLE 2.2 H BRIDGE SWITCH OPERATIONS

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LIST OF FIGURE

FIG 1.1 INDUSTRIAL ROBOT

FIG1.2 AGRICULTURE ROBOT

FIG1.3 TELE ROBOT

FIG1.4 HUMAN ROBOT

FIG1.5 BLOCK DIAGRAM OF EMBEDED SYSTEM

FIG2.1 PIN DIAGRAM OF AT89C51

FIG2.2 AT89C51 IC

FIG2.3 TYPICAL CRSTAL OSCILLATOR

FIG2.4 PULLUP RESISTER

FIG2.5 ELECTROLYTIC CAPACITOR

FIG2.6 BASE IC OF 8PIN AND 40 PIN

FIG2.7 RESISTER

FIG2.8 VOLTAGE REGULATOR

FIG2.9 IR SENSOR

FIG2.10 IR SENSOR CIRCUIT

FIG2.11 PIN CONFIGURATION OF LM324 TOP VIEW

FIG2.12 PIN DIAGRAM OF L293D

FIG2.13 CIRCUIT DIAGRAM OF H BRIDGE

FIG 2.14 BLOCKS DIAGRAM OF L293D

FIG 2.15 DC MOTOR

FIG2.16 GRIPPER

FIG2.17 LIFTER ASSEMBLY

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FIG2.18 WORM DRIVE ARRANGEMENT

FIG2.19 SPUR GEAR,WORM GEAR

FIG2.20 TRACK WHEEL

FIG2.21 METTALIC CHASIS

FIG2.22 BATTERY

FIG2.23 CONNCTION DIAGRAM OF CIRCUIT

FIG4.1 CIRCUIT DIAGRAM

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CHAPTER -1

1.1 INTRODUCTION TO LINE FOLLING ROBOT

A line follower robot is basically a robot designed to follow a ‘line’ or path already

predetermined by the user. This line or path may be as simple as a physical white line

on the floor or as complex path marking schemes e.g. embedded lines, magnetic

markers and laser guide markers. In order to detect these specific markers or ‘lines’,

various sensing schemes can be employed. These schemes may vary from simple low

cost line sensing circuit to expansive vision systems. The choice of these schemes

would be dependent upon the sensing accuracy and flexibility required. From the

industrial point of view, line following robot has been implemented in semi to fully

autonomous plants. In this environment, these robots functions as materials carrier to

deliver products from one manufacturing point to another where rail, conveyor and

gantry solutions are not possible. Apart from line following capabilities, these robots

should also have the capability to navigate junctions and decide on which junction to

turn and which junction ignore. This would require the robot to have 90 degree turn

and also junction counting capabilities. To add on to the complexity of the problem,

sensor positioning also plays a role in optimizing the robots performance for the tasks

mentioned earlier.

Line-following robots with pick- and- placement capabilities are commonly used in

manufacturing plants. These move on a specified path to pick the components from

specified locations and place them on desired locations. Basically, a line-following

robot is a self-operating robot that detects and follows a line drawn on the floor. The

path to be taken is indicated by a white line on a black surface. The control system

used must sense the line and man oeuvre the robot to stay on course while constantly

correcting the wrong moves using feedback mechanism, thus forming a simple yet

effective closed- loop system.

Industrial robots are found in a variety of locations including the automobile and

manufacturing industries. Robots cut and shape fabricated parts, assemble machinery

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FIG 1.1 INDUSTRIAL ROBOT

FIG 1.2 AGRICULTURAL ROBOT

FIG 1.3 TELE ROBOT

and inspect manufactured parts. Some types of jobs robots do: load bricks, die cast,

drill, fasten, forge, make glass, grind, heat treat, load/unload machines, machine parts,

handle parts, measure, monitor radiation, run nuts, sort parts, clean parts, profile

objects, perform quality control, rivet, sand blast, change tools and weld.

Outside the manufacturing world robots perform other important jobs. They can be

found in hazardous duty service, CAD/CAM design and prototyping, maintenance

jobs, fighting fires, medical applications, military warfare and on the farm.

1.2 TYPES OF ROBOTS AS PER APPLICATIONS

Nowadays, robots do a lot of different tasks in many fields.

And this number of jobs entrusted to robots is growing steadily.

That's why one of the best ways how to divide robots into types is

a division by their application.

1.2.1 INDUSTRIAL ROBOTS: Robots today are being utilized

in a wide variety of industrial applications. Any job that involves

repetitiveness, accuracy, endurance, speed, and reliability can be

done much better by robots, which is why many industrial jobs

that used to be done by humans are increasingly being done by

robots.

1.2.2 MOBILE ROBOTS: Also known as Automated Guided

Vehicles, or AGVs, these are used for transporting material over

large sized places like hospitals, container ports, and warehouses,

using wires or markers placed in the floor, or lasers, or vision, to

sense the environment they operate in. An advanced form of the

AGV is the SGV, or the Self Guided Vehicle, like PatrolBot

Gofer, Tug, and Specie-Minder, which can be taught to

autonomously navigate within a space.

1.2.3 AGRICULTURE ROBOTS: Although the idea of robots

planting seeds, ploughing fields, and gathering the harvest may

seem straight out of a futuristic science fiction book, nevertheless there are several

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robots in the experimental stages of being used for agricultural purposes, such as

robots that can pick apples.

1.2.4 TELEROBOTS: These robots are used in places that are hazardous to humans,

or are inaccessible or far away. A human operator located at a distance from a Tele

robot controls its action, which was accomplished with the arm of the space shuttle.

Telerobots are also useful in nuclear power plants where they, instead of humans, can

handle hazardous material or undertake operations potentially harmful for humans.

1.2.5 SERVICE ROBOTS: The Japanese are in the forefront in these types of robots.

Essentially, this category comprises of any robot that is used outside an industrial

facility, although they can be sub-divided into two main types of robots: one, robots

used for professional jobs, and the second, robots used for personal use. Amongst the

former type are the above mentioned robots used for military use, and then there are

robots that are used for underwater jobs, or robots used for cleaning hazardous waste,

like.

HUMANOID ROBOT : A humanoid robot is a robot  with its body shape built to

resemble that of the human body. A humanoid design might be for resemble humans

functional purposes, such as interacting with human tools and environments, for

experimental purposes, such as the study of bipedal locomotion, or for other purposes.

In general, humanoid robots have a torso, a head, two arms, and two legs, though

some forms of humanoid robots may model only part of the body, for example, from

the waist up. Some humanoid robots may also have heads designed to replicate human

facial features such as eyes and mouths. Androids are humanoid robots built to

aesthetically.

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Figure 1…A humanoid robot

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1.3 PROJECT AIM AND OBJECTIVE:

The aim of this project is design an autonomous robot with complete system allow the

robot wander about its environment and to interact with certain object that its

encounter. In order to achieve the aim of this project, several objectives are needed to

be complete.

1.4 IMPORTANCE OF WORK:

In this scenario, the industry having a problem by human life in some hazardous duty

service. Robot can work in environments so hazardous that an unprotected human

would quickly die

1.5 SCOPE OF PROJECT:

Industrial automation, equipment and goods carrier, tour guide in museum, deliver the

mail in office building, delivers medication in the hospital, can be used in place of

crane in various lifting and carriage application.

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Embedded System

Software Hardware

ALPCVB Etc.,

ProcessorPeripheralsmemory

1.6 INTRODUCTION TO EMBEDDED SYSTEMS

An embedded system is a system which is going to do a predefined specified task is

the embedded system and is even defined as combination of both software and

hardware. A general-purpose definition of embedded systems is that they are devices

used to control, monitor or assist the operation of equipment, machinery or plant.

"Embedded" reflects the fact that they are an integral part of the system. At the other

extreme a general-purpose computer may be used to control the operation of a large

complex processing plant, and its presence will be obvious.

All embedded systems are including computers or microprocessors. Some of these

computers are however very simple systems as compared with a personal computer.

The simplest devices consist of a single microprocessor (often called a "chip”), which

may itself be packaged with other chips in a hybrid system or Application Specific

Integrated Circuit (ASIC). Its input comes from a detector or sensor and its output

goes to a switch or activator which (for example) may start or stop the operation of a

machine.

Figure: 1.4 Block diagram of Embedded System

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Embedded consist of both software and hardware:

Memory: It is used to store data or address.

Peripherals: These are the external devices connected

Processor: It is an IC which is used to perform some task

Applications of embedded systems

Manufacturing and process control

Construction industry

Transport

Buildings and premises

Domestic service

Communications

Office systems and mobile equipment

Banking, finance and commercial

Medical diagnostics, monitoring and life support

Testing, monitoring and diagnostic systems

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CHAPTER – 2

HARDWARE DISCRIPTION

2.1 AT89S52 MICROCONTROLLERS:

The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with

4K bytes of programmable Flash memory and erasable read only memory (PEROM).

The device is manufactured using Atmel’s high-density nonvolatile memory

technology and is compatible with the industry- standard MCS-51 instruction set and

pin out. The on-chip Flash allows the program memory to be reprogrammed in-

system or by a conventional nonvolatile memory programmer. By combining a

versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89S52 is a

powerful microcontroller which provides a highly-flexible and cost-effective solution

to many embedded control applications.

2.2 PIN CONFIGURATIONS:

FIGURE 2.1 PIN DIAGRAM AT89S52

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FIGURE2.2AT89S52 IC

2.2.1 Standard Features:

4K bytes of Flash,

128* 8 bits of internal RAM,

32 programmable I/O lines,

Full static operation: 0Hz to 24 MHz

Three level program memory Lock

two 16-bit timer/counters,

a six-vector two-level interrupt architecture,

2.2.2 PIN DESCRIPTION

VCC

Supply voltage.

Port 0

Port 0 is an 8-bit open drain bidirectional I/O port. As an output port, each pin can

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sink eight TTL inputs. When 1s are written to port 0 pins, the pins can be used as

high impedance inputs. Port 0 can also be configured to be the multiplexed low order

address/data bus during accesses to external program and data memory. In this mode,

P0 has internal pull ups. Port 0 also receives the code bytes during Flash

programming and outputs the code bytes during program verification. External pull

ups are required during program verification.

Port 1

Port 1 is an 8-bit bidirectional I/O port with internal pull ups. The Port 1 output

buffers can sink/source four TTL inputs. When 1s are written to Port 1 pins, they are

pulled high by the internal pull ups and can be used as inputs. As inputs, Port 1 pins

that are externally being pulled low will source current (IIL) because of the internal

pull ups. Port 1 also receives the low-order address bytes during Flash programming.

Port 2

Port 2 is an 8-bit bidirectional I/O port with internal pull ups. The Port 2 output

buffers can sink/source four TTL inputs. When 1s are written to Port 2 pins, they are

pulled high by the internal pull ups and can be used as inputs. As inputs, Port 2 pins

that are externally being pulled low will source current (IIL) because of the internal

pull ups. Port 2 emits the high-order address byte during fetches from external

program memory and during accesses to external data memory that use 16-bit

addresses (MOVX @ DPTR). In this application, Port 2 uses strong internal pull-ups

when emitting 1s. During accesses to external data memory that use 8-bit addresses

(MOVX @ RI), Port 2 emits the contents of the P2 Special Function Register. Port 2

also receives the high-order address bits and some control signals during Flash

programming and verification.

Port 3

Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 3 output

buffers can sink/source four TTL inputs. When 1s are written to Port 3 pins, they are

pulled high by the internal pull-ups and can be used as inputs. As inputs, Port 3 pins

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that are externally being pulled low will source current (IIL) because of the pull-ups.

Port 3 also serves the functions of various special features of the AT89S52, as shown

in the following table. Port 3 receives some control signals for Flash Programming.

Table: 2.1 port 3 alternate functions

RST

Reset input. A high on this pin for two machine cycles while the oscillator is running

resets the device.

ALE/PROG

Address Latch Enable (ALE) is an output pulse for latching the low byte of the

address during accesses to external memory. In normal operation, ALE is emitted at a

constant rate of 1/6 the oscillator frequency and may be used for external timing or

clocking purposes. Note, however, that one ALE pulse is skipped during each access

to external data memory. If desired, ALE operation can be disabled by setting bit 0 of

SFR location 8EH. With the bit set, ALE is active only during a MOVX or MOVC

instruction. Otherwise, the pin is weakly pulled high.

PSEN

Program Store Enable (PSEN) is the read strobe to external program memory. When

the AT89S52 is executing code from external program memory, PSEN is activated

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twice each machine cycle, except that two PSEN activations are skipped during each

access to external data memory.

EA/VPP

External Access Enable. EA must be strapped to GND in order to enable the device to

fetch code from external program memory locations starting at 0000H up to FFFFH.

Note, however, that if lock bit 1 is programmed, EA will be internally latched on

reset. EA should be strapped to VCC for internal program executions.

XTAL1

Input to the inverting oscillator amplifier and input to the internal clock operating

circuit.

XTAL2

Output from the inverting oscillator amplifier.

2.2.3 CRYSTAL OSILLATOR

A crystal oscillator is an electronic oscillator circuit that uses the

mechanical resonance of a vibrating crystal of piezoelectric material to create an

electrical signal with a very precise frequency. This frequency is commonly used to

keep track of time (as in quartz wristwatches), to provide a stable clock

signal for digital integrated circuits, and to stabilize frequencies for radio

transmitters and receivers. The most common type of piezoelectric resonator used is

the quartz crystal, so oscillator circuits incorporating them became known as crystal

oscillators, but other piezoelectric materials including polycrystalline ceramics are

used in similar circuits.

Quartz crystals are manufactured for frequencies from a few tens of kilohertz to

hundreds of megahertz. More than two billion crystals are manufactured annually.

Most are used for consumer devices such as wristwatches, clocks, radios, computers,

and cell phones. Quartz crystals are also found inside test and measurement

equipment, such as counters, signal generators, and oscilloscopes.

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A crystal is a solid in which the constituent atoms, molecules, or ions are packed in a

regularly ordered, repeating pattern extending in all three spatial dimensions.

Almost any object made of an elastic material could be used like a crystal, with

appropriate transducers, since all objects have natural resonant frequencies

of vibration. For example, steel is very elastic and has a high speed of sound. It was

often used in mechanical filters before quartz. The resonant frequency depends on

size, shape, elasticity, and the speed of sound in the material. High-frequency crystals

are typically cut in the shape of a simple, rectangular plate. Low-frequency crystals,

such as those used in digital watches, are typically cut in the shape of a tuning fork.

For applications not needing very precise timing, a low-cost ceramic resonator is often

used in place of a quartz crystal.

When a crystal of quartz is properly cut and mounted, it can be made to distort in

an electric field by applying a voltage to an electrode near or on the crystal. This

property is known as electrostriction or inverse piezoelectricity. When the field is

removed, the quartz will generate an electric field as it returns to its previous shape,

and this can generate a voltage. The result is that a quartz crystal behaves like a circuit

composed of an inductor, capacitor and resistor, with a precise resonant frequency.

Quartz has the further advantage that its elastic constants and its size change in such a

way that the frequency dependence on temperature can be very low. The specific

characteristics will depend on the mode of vibration and the angle at which the quartz

is cut (relative to its crystallographic axes). Therefore, the resonant frequency of the

plate, which depends on its size, will not change much, either. This means that a

quartz clock, filter or oscillator will remain accurate. For critical applications the

quartz oscillator is mounted in a temperature-controlled container, called a crystal

oven, and can also be mounted on shock absorbers to prevent perturbation by external

mechanical vibrations.

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Figure 2.3diagram of typical crystal oscillator generating a frequency of 11.0592

MHz

2.2.4 CERAMIC CAPACITOR:

A ceramic capacitor is a fixed value capacitor in which ceramic material acts as the

dielectric. It is constructed of two or more alternating layers of ceramic and a

metal layer acting as the electrode The composition of the ceramic material defines

the electrical behavior and therefore applications. Ceramic capacitors are divided into

two application classes:

Class 1 ceramic capacitors offer high stability and low losses for resonant

circuit applications.

Class 2 ceramic capacitors offer high volume efficiency for buffer, by-pass and

coupling applications.

Ceramic capacitors, especially the multilayer style (MLCC), are the most produced

and used capacitors in electronic equipment that incorporate approximately one

trillion pieces (1000 billion pieces) per year.

Ceramic capacitors of special shapes and styles are used as capacitors for RFI/ MFI

suppression, as feed-through capacitors and in larger dimensions as power capacitors

for transmitter

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2.2.5 Pull-up resister:

Pull up resister are used in electronic logic circuits to ensure that inputs to logic

systems settle at expected logic levels if external devices are disconnected or high

impedance is introduced. They may also be used at the interface between two different

types of logic devices, possibly operating at different power supply voltages

When the switch is open the voltage of the gate input is pulled up to the level of Vin.

When the switch is closed, the input voltage at the gate goes to ground.

A pull-up resistor weakly "pulls" the voltage of the wire it is connected to towards its

voltage source level when the other components on the line are inactive. When all

other connections on the line are inactive, they are high-impedance and act like they

are disconnected. Since the other components act as though they are disconnected, the

circuit acts as though it is disconnected, and the pull-up resistor brings the wire up to

the high logic circuits When another component on the line goes active, it will

override the high logic level set by the pull-up resistor. The pull-up resistor ensures

that the wire is at a defined logic level even if no active devices are connected to it.

A pull-down resistor works in the same way but is connected to ground. It holds the

logic signal near zero volts when no other active device is connected.

.

Figure 2.4 pull up resister

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 ELECTROLYTIC CAPACITOR: electrolytic capacitor is a capacitor that uses

an electrolytic (an ionic conducting liquid) as one of its plates to achieve a larger

capacitance per unit volume than other types. The large capacitance of electrolytic

capacitors makes them particularly suitable for passing or bypassing low-frequency

signals and storing large amounts of energy. They are widely used in power supply

and interconnecting stages of amplifiers at audio frequencies. An electrolytic capacitor

will generally have higher leakage current than a comparable (dry) capacitor, and may

have significant limitations in its operating temperature range, parasitic resistance and

inductance, and the stability and accuracy of its capacitance value.

FIGURE 2…. A Electrolytic capacitor

2.2.7 BASES OF IC : IC sockets are generally for preventing damage to IC's from

soldering and while testing multiple circuits. These are made from Black

Thermoplastic and tin-plated alloy contacts. One end is notched to aid in

identification. They can be mounted end to end to suit longer IC's

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Figure 2.5base of 8 pin

2.2.8 RESISTOR: These do exactly what they say, they resist the flow of electron.

These are necessary for several reasons. They control how much current goes down to

each wire. They control the power uses. They can control voltages (since current,

resistance)

The last point is important as it is the basis of Ohm's law, V=IR. Voltage = Current x

Resistance. For example, suppose you take a resistor and connect the two ends of a

battery with it. You know that your battery is 9V (or whatever) and you know the

resistor is 3Kohm (determined by the color stripes on the resistor), so 9V divided by

3Kohm is .003amps (3 milliamps). So why is this information useful? Well now that

you know the current, you can determine other useful things such as power. P=IV.

You will notice that if you increase resistance, you decrease current. If you decrease

current, you decrease power use. Put a 1ohm resistor between the battery and it will

get so hot it could burn because of the power use. Use a 100Kohm resistor and almost

no power at all will be used.

Figure 2.6 Resistor

2.2.9 VOLTAGE REGULATOR

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Figure 2.7 voltage regulator ic 7805

A voltage regulator is an electrical regulator designed to automatically maintain a

constant voltage level. It may use an electromechanical mechanism, or passive or

active electronic components. Depending on the design, it may be used to regulate one

or more AC or DC voltages. There are two types of regulator are they.

Positive Voltage Series (78xx) and

Negative Voltage Series (79xx)

78xx: ’78’ indicate the positive series and ‘xx’indicates the voltage rating. Suppose

7805 produces the maximum 5V.’05’indicates the regulator output is 5V.

79xx: ’78’ indicate the negative series and ‘xx’indicates the voltage rating.

Suppose 7905 produces the maximum -5V.’05’indicates the regulator output is -5V.

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These regulators consists the three pins there are

Pin1: It is used for input pin.

Pin2: This is ground pin for regulator

Pin3: It is used for output pin. Through this pin we get the output.

2.2.10 IR SENSORS

An Infra-Red sensor detects Infra-Red light/white light from a particular object/line

and then converts light energy to electrical energy. An IR sensor pair consists of an

emitter and a detector. The emitter is blue in color and the detector can be grey, black

or white in color.

figure 2.8 IR sensor

2.2.11 IR EMITTER

An infra-red emitter is a Light Emitting Diode (LED) made from Gallium Arsenide. It

detects IR energy at a wavelength of 880nm and emits the same. The infrared

phototransistor acts as a transistor with the base voltage determined by the amount of

light hitting the transistor. Hence it acts as a variable current source. Greater amount

of IR light cause greater currents to flow through the collector-emitter leads.

The variable current traveling through the resistor causes a voltage drop in the pull-up

resistor. This voltage is measured as the output of the device.

2.2.12 IR DTECTOR

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An infra-red detector is a photo detector. It detects IR energy emitted by the emitter

and converts it into electrical energy.

 The main principle involved in the conversion of light energy to electrical energy is

PHOTOELECTRIC EFFECT.

 IR sensor circuit to detect a black line on white background:

Fig: 2.9. IR sensor circuit

The output is taken at negative terminal of IR detector.

The output can be taken to a microcontroller either to its ADC (Analog to Digital

Converter) or LM 339 can be used as a comparator.

2.2.13 LM 324

2.2.13.1 FEATURES:

Wide gain bandwidth : 1.3MHZ input common-mode voltage range

Includes ground .large voltage gain: 100DB .very low supply current/amplify :

375ma low input bias current : 20NA low input offset voltage : 5mv max.

Low input offset current : 2NA wide power supply range :

Single supply : +3v to +30v

Dual supplies : ±1.5v to ±15v

It is a comparator ic

2.2.13.2 DESCRIPTION

These circuits consist of four independent, high gain, internally frequency

compensated operational amplifiers .They operate from a single power supply over a

wide range of voltages. Operation from split power supplies is also possible and the

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low power supply current drain is independent of the magnitude of the power supply

voltage.

Fig:2.10. pin configuration top view

2.2.14 L293D( H-BRIDGE):

4 5 12 13

16 8

1

2

15

9

7

10

314

6

11

VCC1- LOGIC SUPPLY= 5V

LM+ OUTPUT FOR MOTOR1

OUTPUT FOR MOTOR2

L_IN1

L_EN

GND

L293DINPUT LINES

R_EN

L_IN2

R_IN2

R_IN1

LM-

RM+

RM-

Figure 2.11 PIN DIAGRAM OF L293D IC

Motor are arrange in a fashion called H bridge. H bridge is an electronics circuits

which enables a voltage to be applied across the load in either direction. It allow a

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circuit full control, that is an H bridge, a microcontroller logic chip, or remote control

can electronically command the motor to go forward ,reverse and brake

An H-bridge is an electronic circuit which enables DC electric motors to be run

forwards or backwards. These circuits are often used in robotics. H-bridges are

available as integrated circuits, or can be built from discrete components.

Figure 2.12 circuit diagram of H bridge

The two basic states of a H-bridge. The term "H-bridge" is derived from the typical

graphical representation of such a circuit. An H-bridge is built with four switches

(solid-state or mechanical). When the switches S1 and S4 (according to the first

figure) are closed (and S2 and S3 are open) a positive voltage will be applied across

the motor. By opening S1 and S4 switches and closing S2 and S3 switches, this

voltage is reversed, allowing reverse operation of the motor.

Using the nomenclature above, the switches S1 and S2 should never be closed at the

same time, as this would cause a short circuit on the input voltage source. The same

applies to the switches S3 and S4. This condition is known as shoot-through.

2.2. 13.1 OPERATION

The H-Bridge arrangement is generally used to reverse the polarity of the motor, but

can also be used to 'brake' the motor, where the motor comes to a sudden stop, as the

motors terminals are shorted, or to let the motor 'free run' to a stop, as the motor is

effectively disconnected from the circuit. The following table summarizes operation.

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S1 S2 S3 S4 Result

1 0 0 1 Motor moves right

0 1 1 0 Motor moves left

0 0 0 0 Motor free runs

0 1 0 1 Motor brakes

Table: 2.2 H-bridge switch operation

2. 2.13.2 H-BRIDGE DRIVER

The switching property of this H-Bridge can be replaced by a Transistor or a Relay or

A Mosfet or even by an IC. Here we are replacing this with an IC named L293D as

the driver whose description is as given below. The Device is a monolithic integrated

high voltage, high current four channel driver designed to accept standard DTL or

TTL logic levels and drive inductive loads as and switching power transistors. To

simplify use as two bridges each pair of channels is equipped with an enable input. A

separate supply input is provided for the logic, allowing operation at a lower voltage

and internal clamp diodes are included. This device is suitable for use in switching

applications at frequencies up to 5 kHz. The L293D is assembled in a 16 lead plastic

package which has 4 center pins connected together and used for heat sinking The

L293D is assembled in a 20 lead surface mount which has 8 center pins connected

together and used for heat sinking.

2. 13.3 FEATURES

600mA OUTPUT CURRENT CAPABILITY

PER CHANNEL

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1.2A PEAK OUTPUT CURRENT (non repetitive)

ENABLE FACILITY

OVERTEMPERATURE PROTECTION

LOGICAL "0" INPUT VOLTAGE UP TO 1.5 V

(HIGH NOISE IMMUNITY)

INTERNAL CLAMP DIODES

2.2.13.4 BLOCK DIAGRAM:

Figure 2.13block diagram of LM293D

2.2. 14 DC MOTORS:

These are very commonly used in robotics. DC motors can rotate in both directions

depending upon the polarity of current through the motor. These motors have free

running torque and current ideally zero. These motors have high speed which can be

reduced with the help of gears and traded off for torque. Speed Control of DC motors

is done through Pulse Width Modulation techniques, i.e. sending the current in

intermittent bursts. PWM can be generated by 555 timer IC with adjusted duty cycle.

Varying current through the motor varies the torque.

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FIGURE 2.14(DC MOTOR

GRIPPER ARM: The gripper module is state of the art robotic arm which can be

used in various 'pick and place' kind of robots. It works on DC Motor (9 to 12V

DC).

Change in rotation direction of the DC Motor, generates Jaw Open & Close

Action.

The DC motor can be easily be controlled with the help of DPDT Switch (manual

mode) or with the help of any micro controller along with L293D Motor Driver

module.

FIGURE3…Gripper orthogonal view, main view

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LIFTER ASSEMBLY: It is made from laser cut Metal and acrylic. There is

a worm gear and spur gear assembly which is attached with a DC motor (9 to

10 volt) to provide torque so that gripper can pick and lift the load.

Figure 3…..Lifter assembly

LIFTER PARTS:

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•  Gripper assembly Plates.

 •  Fiber Grippers-2nos.

 •  45 RPM Motor-1nos.

 •  Worm Gear-1nos.

 •  Spur Gear-2nos.

 •  Different Screws and nuts.

Worm drive: Worm drive is a gear arrangement in which a worm (which is a gear in

the form of a screw) meshes with a worm gear (which is similar in appearance to

a spur gear, and is also called a worm wheel). The terminology is often confused by

imprecise use of the term worm gear to refer to the worm, the as a worm gear, or the

worm drive unit.

Like other gear arrangements, a worm drive can reduce rotational speed or allow

higher torque to be transmitted. The image shows a section of a gear box with a worm

gear being driven by a worm. A worm is an example of a screw, one of the six simple

machines.

Figure: 3.12 worm drive arrangement

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(a) (b)

Figure 3.125 (a) Spur gear (b) Worm gear, (Made by acrylic fiber)

TRACK WHEEL: Track wheel is a circular wheel with rubber grip fastened on DC

motor shaft by screw. Track wheel provide help in movement of robot in any

direction.

Figure 3.125 Track wheel

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CHASSIS: A chassis  consists of an internal framework that supports a man-made

object in its construction and use. It is analogous to an animal's skeleton. An example

of a chassis is the under part of a motor vehicle, consisting of the frame (on which the

body is mounted). Here metallic chassis is used.

FIGURE 3.212 A metallic chassis

POWER SUPPLY: To provide energy to DC motors for movement of robot A

Battery of DC (6 volt to 12 V, 4.5A) is being used.

Figure 3.225 Battery

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2.3 CIRCUIT DIAGRAM:

FIGURE 2.15 CONNECTION DIAGRAM OF CIRCUIT)

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3. WORKING PROCEDURE

3.1 WORKING

Robotics is an interesting subject to discuss about and in this advanced world Robots

are becoming a part of our life. In this project we are going to discuss about a robot

which is capable of following a line without the help of any external source.

The Embedded Line following robot uses four motors to control rear wheels and the

single front wheel is free. It has 2-infrared sensors on the bottom for detection of

white tracking tape. When the middle sensor detects the black color, this sensor output

is given to the comparator LM324. The output of comparator compares this sensor

output with a reference voltage and gives an output. The output of comparator will be

low when it receives an input from the sensor

When a sensor is on the black line it reads 0 and when it is on the bright

surface read 1. and sensor module gives the value to controller to generate

control signal according to programmer

When both right and left sensors are on bright surface (read 1) then both

couple of motor move.

When left sensor comes in black (for white line tracer) region then left motor

stops while right motor continue to move so that left turn takes place and robot

returns on black line.

When right sensor comes in black region then right motor stops while left

motor continue to move so that right turn takes place and robot returns on

black line.

By correcting the path robot move to destination.

When both sensors comes on black surface simultaneously (read 0) than both

motor stop.

39

When both sensor read 0 simultaneously and both wheel motor stops than

immediately motor for right and left movement of lifter arm start moving for

some definite time duration using Timer of controller.

After movement of left- right motor of lifter the motor for lifting and gripping move

one by one for some definite time duration defined in program using timer of

controller.

The lifter and gripper arm have various gear arrangement, so that after

movement of each motor of arm one by one the arm pick an object or work

piece softly.

After movement of gripper motor, all the motor of arm starts moving in

reverse direction of previous movement, one by one.

After picking an object by gripper and lifter arm, either left or right wheel

motor starts moving until the robot reverts his path and both sensor comes on

bright surface after crossing a black surface between.

After reversing the path robot move by correcting path and reach to destination

At destination both sensors read 0 simultaneously, so that previous process is

repeated and the object is now placed by same movement of motor.

The robot revert its path and repeats the pick and place process again and again

continuously.

3.2 ADVANTAGES

Robot movement is automatic.

Fit and Forget system.

Used for long distance applications.

Defense applications.

Used in home, industrial automation.

Cost effective.

Simplicity of building

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3.3 DISADVANTAGES

LFR follows a black line about 1 or 2 inches in width on a white surface.

LFR are simple robots with an additional sensors placed on them.

Needs a path to run either white or black since the IR rays should reflectfrom

the particular path.

Slow speed and instability on different line thickness or hard angles.

3.4 APPLICATIONS:

Guidance system for industrial robots moving on shop floor etc.

Industrial applications.

Home applications.

CHAPTER 4

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4. SOFTWARE TOOLS

4.1 KEIL SOFTWARE:

Keil compiler is software used where the machine language code is written and

compiled. After compilation, the machine source code is converted into hex code

which is to be dumped into the microcontroller for further processing. Keil compiler

also supports C language code.

#include<reg51.h>

sbit m1=P0^0;

sbit m2=P0^1;

sbit m3=P0^2;

sbit m4=P0^3;

sbit m5=P0^4;

sbit m6=P0^5;

sbit m7=P0^6;

sbit m8=P0^7;

sbit ma=P3^6;

sbit mb=P3^7;

sbit sens1=P1^0;

sbit sens2=P1^1;

void delay(int);

void main()

{

m1=0;

m2=0;

m3=0;

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m4=0;

m5=0;

m6=0;

m7=0;

m8=0;

ma=0;

mb=0;

sens1=1;

sens2=1;

while(1)

{

while((sens1==1)&&(sens2==0))

{

m1=1;

m2=0;

m3=0;

m4=0;

m5=0;

m6=0;

m7=0;

m8=0;

ma=0;

mb=0;

}

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while((sens1==0)&&(sens2==1))

{

m1=0;

m2=0;

m3=1;

m4=0;

m5=0;

m6=0;

m7=0;

m8=0;

ma=0;

mb=0;

}

while((sens1==1)&&(sens2==1))

{

m1=1;

m2=0;

m3=1;

m4=0;

m5=0;

m6=0;

m7=0;

m8=0;

ma=0;

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mb=0;

}

while((sens1==0)&&(sens2==0))

{

m1=0;

m2=0;

m3=0;

m4=0;

m5=1;

m6=0;

m7=0;

m8=0;

ma=0;

mb=0;

delay(500);

m1=0;

m2=0;

m3=0;

m4=0;

m5=0;

m6=0;

m7=1;

m8=0;

ma=0;

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mb=0;

delay(500);

m1=0;

m2=0;

m3=0;

m4=0;

m5=0;

m6=0;

m7=0;

m8=0;

ma=1;

mb=0;

delay(500);

m1=0;

m2=0;

m3=0;

m4=0;

m5=0;

m6=0;

m7=0;

m8=0;

ma=0;

mb=0;

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m1=0;

m2=0;

m3=0;

m4=0;

m5=0;

m6=0;

m7=0;

m8=0;

ma=0;

mb=1;

delay(500);

m1=0;

m2=0;

m3=0;

m4=0;

m5=0;

m6=0;

m7=0;

m8=0;

ma=0;

mb=0;

m1=0;

m2=0;

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m3=0;

m4=0;

m5=0;

m6=0;

m7=0;

m8=1;

delay(500);

m1=0;

m2=0;

m3=0;

m4=0;

m5=0;

m6=0;

m7=0;

m8=0;

m1=0;

m2=0;

m3=0;

m4=0;

m7=0;

m8=0;

m5=0;

m6=1;

48

delay(500);

m1=0;

m2=0;

m3=0;

m4=0;

m7=0;

m8=0;

m5=0;

m6=0;

m1=1;

m2=0;

m3=0;

m4=0;

m5=0;

m6=0;

m7=0;

m8=0;

while(sens1==0);

while(sens1==1);

while(sens1==0);

delay(20);

m1=0;

49

m2=0;

m3=0;

m4=0;

m5=0;

m6=0;

m7=0;

m8=0;

}

}

}

void delay(int x)

{

int y,z;

for(y=0;y<x;y++)

for(z=0;z<1275;z++);

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}

4.4 RESULT

The objective of the line following robot is to follow a line on its given path which is

obtained for which it uses IR sensors which detects the line and sends the information

to LM324 comparator and then to H bridge which controls the working of the wheel’s.

Microcontroller controls the other operations.

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4.2 SAFETY REQUIREMENTS

The various safety requirements which were considered while designing the robot are decided as follows:

1. The Robot should not be programmed such that it should damage the Battery while holding it in its gripper.

2. Correct holding position should be set as if it not set then while movement of the Robot it may drop the Lead Batteries which can arise a Hazardous situation in the industry.

3. The Robot should be interfaced properly with the sensors been placed near the Belt conveyor so as to know when the belt conveyor is to be stopped or to be started to move the batteries ahead.

4. Load carrying capacity should be maintained as it should be always more than the default load which is to be shifted.

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CONCLUSION AND FUTURE SCOPE

CONCLUSION:

In this project we have studied and implemented a Line Following Robot using a

Microcontroller for blind people. The programming and interfacing of microcontroller

has been mastered during the implementation.

FUTURE SCOPE:

Smarter versions of line followers are used to deliver mails within office

building and deliver medications in a hospital.

This technology has been suggested for running buses and other mass transit

systems and may end up as a part of autonomous cars navigating the freeway.

Used in heavy machinery industry

Used where high load and risky operation going on

Use in place of the crane

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REFERENCES :

www.avrfreaks.com,Microcontrollers,Atmel

septiembre-2001. www.atmel.com

The 8051 Microcontroller and Embedded Systems Using Assembly and C

By Muhammad Ali Mazidi, Janice Gillispie Mazidi & Ro linD. McKinley

Atmel Corp. Makers of the AVR

microcontroller

www.atmel.com

www.electronic projects.com

www.howstuffworks.com

Electrikindia.

EMBEDDED SYSTEM BY RAJ KAMAL

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