Robotic Arm ,,Bk

8/2/2019 Robotic Arm ,,Bk

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PROJECT REPORT

ON

INDUSTRIAL ROBOT

Submitted by:BRIJINDER KUMAR 009236104633) SACHIN KUMAR (009236104690)

ANKUR SAINI (009236127886) AMAN BANSAL (009236104622)

Submitted to: SubmitteddateMr. H D SEKHRIHODDepartment of Electronic & Communication.


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CERTIFICATE

This is to certify that the project entitled

INDUSTRIAL

ROBOT

Submitted by Mr. H. D. SEKRI, Mrs. SIMRANJEET

KAUR towards the partial fulfilment of the requirement for

the award of thediploma of Electronics & Communication

Engineering is a record of a work submitted has inmy

opinion reached a level required for being acceptedforexamination.

GUIDE:

Mrs. SIMRANJEET KAUR

Class Incharge

Electronics Department,

Govt. Polytechnic College, Khunimajra

MOHALI .

COUNTERSIGNED:

Mr. HARI DAS SEKRIHead of Department

,Electronics & Communication Engg.


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ACKNOWLEDGEMENT

We are grateful to the department of Electronics Engineering for

their kind cooperation and help in accomplishment of this project.

We would especially like to thank our special advisor Mr. H. D.

Sekri head of department of Government polytechnic college,

khunimajra Mohali and Mrs. Simranjeet kaur class incharge ECE

Department of for their perspective guidance which helped us

greatly & pointed us in right direction with this project


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INTRODUCTION

Robotics

The word robotics, meaning the study of robots was coined by

Isaac Asimov. Robotics involves elements of both mechanical and

electrical engineering, as well as control theory, computing and now

artificial intelligence (Selig, 1992). According to the Robot Institute

of America, A robot is a reprogrammable, multifunctionalmanipulator designed to move materials, parts, tools or specialized

devices through variable programmed motions for the performance

of a variety of tasks(Robotics Research Group, ) The fact that a

robot can be reprogrammed is important: it is definitely a

characteristic of robots.

Activities of daily life (ADL) such as picking up a telephone or

drinking a cup of coffee are taken very much for granted by most

people. Humans have an innate ability to exist in and manipulate

environments. Moving from one location to another, acquiring, and

manipulating an object is something most of us do without much

effort. We are so adept at these tasks that we almost forget how

complex they can be. However, people with neuromuscular

impairments (e.g. spinal cord injury, stroke, multiple sclerosis, etc.)

may be confined to wheelchairs and rely on others for assistance.

For them, executing an ADL is anything but trivial. Traditionally, a

dedicated caregiver is needed, thus the disabled person cannot

absolutely control when an ADL is aided or performed for them.


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Prior research has shown that users are very interested in tasks that

occur regularly in unstructured environments. These include pick-

and-place tasks such as lifting miscellaneous objects from the floor

or a shelf [1]. Our goal is to provide methods for independent

manipulation of unstructured environments to wheelchair-confined

people using a Rf-car-mounted robot arm for manipulation. We want

a simple interface where the user can specify the end goal such as

picking up a glass of water by pointing to the glass. Another

example is navigating to a hotel room. From the hotel lobby, we

need to navigate to the elevator lobby, call for the elevator, locate

and push the desired elevator button, proceed to the hotel room

itself, open the door and enter. However, instead of micromanaging

each section of the task, the user could simply specify Room 219

as their destination. In this initial phase of research, we investigate

the use of a visual interface as a source of input.

Introduction of Robotics

The word robot was derived from Czech word robot a which meansa forced labourer then later a well known Russian science fiction

writer Isaac Asimov coined the word robotics. From there on various

different developments are being successfully done till date in the

field of robotics in the form of teleported manipulators,

humanoids ,micro robots etc. as the trend of the industry is moving

from the current state of automation to robotization . Thus the robot

technology is advancing rapidly. Now a days the most commonly

used robots in industry is a robotic manipulator or a robotic arm

.Robotic arm is basically an open closed kinematics chain of rigid

links interconnected by movable joints. The end of the arm is

connected to the end-effectors. The end-effecter may be a tool and


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its fixture or a gripper or any other device to do the work. The end-

effecter is similar to the human hand with or without fingers.

Type of robot

Jointed arm on RF car configuration.

OBJECTIVE

The primary objective is to make the Robotic arm, which comprises

of three gear motors, to interface with the In Material published as

part of this publication, either on-line or in print, is copyrighted.

Permission to make digital or paper copy of part or all of these

works for personal or classroom use is granted without fee provided

that the copies are not made or distributed for profit or commercial

advantage AND that copies 1) bear this notice in full and 2) give thefull citation on the first page. It is permissible to abstract these

works so long as credit is given. To copy in all other cases or to

republish or to post on a server or to redistribute to lists requires

specific permission and payment of a fee. Development of a

Microcontroller Based Robotic Arm atmel 8051-based micro-

controller. It provides more interfaces to the outside world and has

larger memory to store many programs. Scope The scope of this

work involves confirming the 8051 micro-controller Input/Output

(I/O) signals are compatible with that of the robotic arm stepper

motors and testing of the robots motor signals through

programming the 8051 microcontroller. Assembly programming is

used to develop the programs for the EPROM 2732 on the 8051


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micro-controller platform that takes robots motor signal as I/O and

controls the robot operation programmatically. We have assumed

that after figuring out the interface issues for the Robot with the

8051 microcontroller, the same knowledge can be extended to

make very complex robots with enhanced functionality.

ABSTRACT

Now days in this fast growing industrial age every company needs

speed in manufacturing to cope up with the customers

requirements. Every industrialist cannot afford to transform his unit

from manual to semiautomatic or fully automatic as automation is

not that cheap in India. The basic objective of our project is to

develop a versatile and low cost robotic arm which can be utilized in

any industry to eliminate this problem. Our robotic arm can be used

in number of application by changing the program of controller and

the structure is designed in such a way that it is capable to lift light

loads but can also lift medium loads. Our robotic manipulator would

be used mainly in the packaging department and automatic

assembly lines.


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BLOCK DIAGRAM


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CIRCUIT DIAGRAM


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Remote circuit

RECEIVER CIRCUIT


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Receiver circuit

WORKING OF CIRCUIT


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This is the control panel of the system as it oversees the operations

of the mechanical arm, The MCU 8051 of the control unit acts as the

brain of the control panel as it coordinates all the activities of the

other devices. When power (+5V) was supplied to the control unit,

the MCU started off by loading the program from the EPROM

M2732A, interpreted and executed the instruction codes through

the various operational principles which had been de-scribed in

details in chapter three (session 3.2). The 8051 then sends signal

to the stepper motor which moves step. The stepper motor (M3) at

the wrist first moves five times (45) turning the gears to cause adownward movement of the hand. The stepper motor at the

shoulder (M2) moves next stepping five times (45) and makes the

connected gears to cause the movement of the arm 45 forward.

Then the stepper motor at the base(M1moves either ten times (90)

or twenty times (180), depending on the button pressed, causing

the whole structure to turn from right to left( or vice versa) through

the connected gears. The magnetic coil resting on the hand

becomes magnetized immediately the last gear on the hand stops

moving. Then, it magnetizes (picks) any magnetic material it can

find and then M3 and M2 moves the arm up while M1 moves

(rotates the structure) from left to right (or vice versa) and then the

8051 demagnetizes the magnetic coil thereby making the hand to

drop the metallic object.

Results

This work is able to successfully accomplish the defined

functionality. A sample robot which can rotate, magnetize an object,

lower and raise its arm, by being controlled by the 8051

microcontroller is built successfully. The 8051-development board is


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CIRCUIT COMPONENT

Remote section

1.RF MODULE

2.HT12E, HT12D

3.Push switch(10)

4.Microcontroller(1)

5. Resistor (20).

6.Capacitor(5)

7.Toggle switch(1)-

8. Crystal(1)

9.Ic 7805

Car section

1. Sip(1)

2. Toggle switch(1)

3. Resistor(10)

4. Capacitor(5)-


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5. Crystal(1)

6. Microcontroller(1)

7. Ic 7805

8. L293 dne(4)

9. L.E.D.

10. Gear motor(7*300/pc)

11. P.C.B.

12. Connector

13.Connecting ,ant wire(5-mt)

14. Solder wire

Robot mechanism

1. Aluminum sheet

2. Al. Pipe Al. Strip

3. Al. Clamp

4. wheel

5. Battery (2)

6. Screws

7. Grip, Welding, drilling


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DESCRIPTION OF COMPONENT

Power Supply

The RCT-433-AS is designed to operate from a 1.5- 12V power supply. It is crucial

that this power supply be very quiet. The power supply should be bypassed using a

0.01uF low-ESR ceramic capacitor and a 4.7uF tantalum capacitor. These capacitors

should be placed as close to the power pins as possible.

RF Based Wireless Remote using RX-TX MODULES (434MHz.)

Summary of the project

This circuit utilizes the RF module (Tx/Rx) for making a wirelessremote, which could be used to drive an output from a distantplace. RF module, as the name suggests, uses radio frequency tosend signals. These signals are transmitted at a particular frequencyand a baud rate. A receiver can receive these signals only if it isconfigured for that frequency.A four channel encoder/decoder pair has also been used in thissystem. The input signals, at the transmitter side, are taken throughfour switches while the outputs are monitored on a set of four LEDscorresponding to each input switch. The circuit can be used fordesigning Remote Appliance Control system. The outputs from thereceiver can drive corresponding relays connected to any .


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DescriptionThis radio frequency (RF) transmission system employs

Amplitude Shift Keying (ASK) with transmitter/receiver (Tx/Rx) pair

operating at 434 MHz. The transmitter module takes serial input and

transmits these signals through RF. The transmitted signals are

received by the receiver module placed away from the source of

transmission.

The system allows one way communication between two nodes,

namely, transmission and reception. The RF module has been used

in conjunction with a set of four channel encoder/decoder ICs. Here

HT12E & HT12D have been used as encoder and decoder

respectively. The encoder converts the parallel inputs (from the

remote switches) into serial set of signals. These signals are serially

transferred through RF to the reception point. The decoder is used

after the RF receiver to decode the serial format and retrieve the

original signals as outputs. These outputs can be observed on

corresponding LEDs.

Encoder IC (HT12E) receives parallel data in the form of address bitsand control bits. The control signals from remote switches along

with 8 address bits constitute a set of 12 parallel signals. The

encoder HT12E encodes these parallel signals into serial bits.

Transmission is enabled by providing ground to pin14 which is

active low. The control signals are given at pins 10-13 of HT12E. The

serial data is fed to the RF transmitter through pin17 of HT12E.


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Transmitter, upon receiving serial data from encoder IC (HT12E),

transmits it wirelessly to the RF receiver. The receiver, upon

receiving these signals, sends them to the decoder IC (HT12D)

through pin2. The serial data is received at the data pin (DIN, pin14)

of HT12D. The decoder then retrieves the original parallel format

from the received serial data.

When no signal is received at data pin of HT12D, it remains in

standby mode and consumes very less current (less than 1 A) for a

voltage of 5V. When signal is received by receiver, it is given to DIN

pin (pin14) of HT12D. On reception of signal, oscillator of HT12D

gets activated. IC HT12D then decodes the serial data and checks

the address bits three times. If these bits match with the local

address pins (pins 1-8) of HT12D, then it puts the data bits on its

data pins (pins 10-13) and makes the VT pin high. An LED is

connected to VT pin (pin17) of the decoder. This LED works as an

indicator to indicate a valid transmission. The corresponding output

is thus generated at the data pins of decoder IC. A signal is sent bylowering any or all the pins 10-13 of HT12E and corresponding

signal is received at receivers end (at HT12D). Address bits are

configured by using the by using the first 8 pins of both encoder and

decoder ICs. To send a particular signal, address bits must be same

at encoder and decoder ICs. By configuring the address bits

properly, a single RF transmitter can also be used to control

different RF receivers of same frequency.

To summarize, on each transmission, 12 bits of data is transmitted

consisting of 8 address bits and 4 data bits. The signal is received at

receivers end which is then fed into decoder IC. If address bits get

matched, decoder converts it into parallel data and the

corresponding data bits get lowered which could be then used to


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drive the LEDs. The outputs from this system can either be used in

negative logic or NOT gates (like 74LS04) can be incorporated at

data pins.


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COMPONENTS USED

1. HT12D DECODER

Download Datasheet: HT12D.pdf

HT12D IC comes from HolTek Company. HT12D is a decoder integrated circuit that

belongs to 212 series of decoders. This series of decoders are mainly used for remote

control system applications, like burglar alarm, car door controller, security system

etc. It is mainly provided to interface RF and infrared circuits. They are paired with

212 series of encoders. The chosen pair of encoder/decoder should have same number

of addresses and data format. In simple terms, 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. Pin Diagram


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Pin Description Pin

Number

Function Name

1 8 BIT ADDRESS

PINS FOR INPUT

A0

2 A13 A2

4 A3

5 A4

6 A5

7 A6

8 A7

9 GROUND (0V) GROUND

10 4 BIT

DATA/ADDRESSPINS FOR OUTPUT

D0

11 D1

12 D2

13 D3

14 SERIAL DATA

INPUT

INPUT

15 OSCILLATOR

OUTPUT

OSC 2

16 OSCILLATOR

INPUT

OSC 1

17 VALID

TRANSMISSION,

ACTIVE HIGH

VT

18 SUPPLY VOLTAGE;

5V (2.4 12V)

Vcc


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Transmitter section (Remote controller)

Remote access is the ability to get access to a network from a

remote distance. It is the controller part of our CAR. It givesdirections to the vehicle whatever we want to do with our vehicle

like to move forward or reverse, to turn left or right, to adjust the

direction of the ARM we have placed on it to record several

locations or sites. It sends various codes to the receiver section

with the help of FM transmitter we have connected on it

wirelessly. It consists of

RF Transmitter

HT12E IC

A Voltage Regulator

8 Push Buttons

A communication kit of 8051 microcontroller

Selection of motor

Many different motors are available in the market like servo

motors, stepper motor car synchronous motors, dc motors with

and with out gears. These different motors are used according to

their applications and requirements for e.g. If we want high

torque and precise position we need to use dc gears motors, if we

want to only position and if high torques not required then

stepper motors are used .Dc geared motors are used where we

need high torque .For only smooth motion dc motors are used

.Here we have used stepper motor as though servo are best

suited for robotics it wasnt economically viable .Stepper motors


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are of many types for e.g. Variable reluctance motors, permanent

magnet motors and hybrid motors.

Introduction of D.C motor:-

Now a days DC motors plays a vital role in most of the industrial

areas, it can be seen in most of the electronic devices. They are

mainly used for the mechanical movements of physical

applications such as rolling the bundle of sheets or CD drives, lifts

etc.

Many methods evolved to control the revolution of a motor. DC

motors can be controlled either by software or directly by

hardware. Software controlling needs computers which are bulky

and common man cannot afford for it, so hardware controls are in

use. Even in hardware if it is programmable device then it is

preferred because it can be modeled according to the

requirements of the user. Advantages of using uc over other

controlling devices for controlling the DC motor are given below:


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1. SPEED:The execution of an instruction in PIC IC is very fast (in

micro seconds) and can be changed by changing the oscillator

frequency. One instruction generally takes 0.2 microseconds.

2. COMPACT: The PIC IC will make the hardware circuitry

compact.

3. RISC PROCESSOR: The instruction set consists only 35

instructions.

4. EPROM PROGRAM MEMORY: Program can be modified and

rewritten very easily.

5. INBUILT HARDWARE SUPPORT: Since PIC IC has inbuilt

programmable timers, ports and interrupts, no extra hardware is

needed.


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6. POWERFUL OUTPUT PIN CONTROL: Output pins can be

driven to high state, using a single instruction. The output pin can

drive a load up to 25mA.

7. INBUILT I/O PORTS EXPANSIONS: This reduces the extra

ICs which are needed for port expansion and port can be

expanded very easily.

8. INTEGRATION OF OPERATIONAL FEATURES: Power on

reset and brown/out protection ensures that the chip operates

only when the supply voltage is within specification. A watchdog

timer resets if the chip ever malfunctions and deviates from its

normal operation.

3

Working Principle

It is based on the principle that when a current-carrying conductor

is placed in a magnetic field, it experiences a mechanical force

whose direction is given by Fleming's Left-hand rule and whose

magnitude is given by Force, F = B I l Newton Where B is the

magnetic field in weber/m2.I is the current in amperes and is the

length of the coil in meter. The force, current and the magnetic

field are all in different directions. If an Electric current flows

through two copper wires that are between the poles of a

magnet, an upward force will move one wire up and a downward

force will move the other wire down.


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The loop can be made to spin by fixing a half circle of copper

which is known as commutator, to each end of the loop. Current is

passed into and out of the loop by brushes that press onto the

strips. The brushes do not go round so the wire do not get

twisted. This arrangement also makes sure that the current

always passes down on the right and back on the left so that the

rotation continues. This is how a simple Electric motor is made.

Figure 1: Force in DC Motor


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Figure 2 : Magnetic Field in DC Motor

Figure 3 : Torque in DC Motor


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Figure 4 : Current Flow in DC Motor

Calculations for torque

Motor ratings:-

VOLTAGE =12V

CURRENT =0.6A

GEAR RATIO =1:20

1) POWER:-P =V*I=7.2 W

2) Angular speed:- =2 N=2*3.14*38=3.97 rps

3) Torque:-T=0.8*P/ (because 0.8=motor efficiency)=1.45 Nm

By using the formula T=F*R the load lifting capacity of our motor

is

0.328kg.


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Control of motor

There are mainly three types of controls which are used:-

1) Micro controller IC

Circuit for controlling four d.c motors

This circuit is mainly used to drive low voltage d.c motors. It takes

the input from the controller side and according to the number of

pulses given it controls the motor. Plc is used to control the

circuit. It contains L293D ic which is the main driver of the motor.

When dc power is given to the circuit it gets converted into 12v

with the help of ic7812.this 12v are converted into 6v with the

help of ic7806. this 6v is use as the input voltage. There are four

enables in the icL293D which I used to turn on/off the ic.Vcc1 is

the supply voltage and Vcc2 is the output supply voltage for the

motor. This circuit can run motor in both the directions


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Circuit for controlling four dc motors:-


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L293D (IC) INTEGRATED CIRCUIT

1. L293D ic:- it is the quadruple current half h driver. It is

designed to provide bidirectional current from voltages 4.5

to36 volts. It is designed to drive inductive loads such as

relays solenoids dc motors. All inputs are compatible. Each

output is complete totem pole with darling ton transistor

sink and a suede Darlington source. It has two enables.

When enables are high the driver associated to it r high and

vice versa.


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DESCRIPTION

The L293B and L293E are quad push-pull drivers capable

of delivering output currents to 1Aperchan-nel. Each

channel is controlled by a TTL-compatible logic input and

each pair of drivers (a full bridge) is equipped with an

inhibit input which turns off all four

transistors .A separate supply input is provided for the

logic so that it may be run off a lower voltage to reduce

dissipation. Additionally, the L293E has external

connection of sensing resistors, for switch mode control.

The L293Band L293Earepackagein 16 and 20-pin plastic

DIPs respectively both use the four centre pins to

conduct heat to the printed circuit board.

FIG.6 L293D IC


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Internal diagram of L293D IC

CIRCUIT DIAGRAM FOR CONTROLLING D.C MOTORS

As shown in fig. the output from plc goes to pin number 2 of the ic

which drives the motor in forward direction. When the motor is to

be driven in reverse direction the input from plc is given to pin

number 7.second motor can be run using pin number 15 and 10

in forward and reverse direction. The internal circuit shows the

working similar as a h bridge circuit.


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MOUNTING OF HEAT SINK

The external heat sink or printed circuit copper area must be

connected to electrical ground.

MOUNTING INSTRUCTIONS

The Rth j-amb of the L293B and the L293Ecan be reduced by

soldering the GND pins to a suitable copper area of the printed

circuit board as shown in figure 12 or to an external heat sink

(figure 13).During soldering the pins temperature must not

exceed 260oC and the soldering time must not be longer than 12

seconds. The external heat sink or printed circuit copper area

must be connected to electrical ground. Figure 12 :Example of

P.C. Board Copper Area which is Used as Heat sink Figure 13

:External Heat sink Mounting Example (Rth = 30oC)


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IC L293

The L293 and L293D are quadruple high-current half-H drivers.

The L293 is designed to provide bidirectional drive currents of up

to 1 A at voltages from 4.5 V to 36 V. The L293D is designed to

provide bidirectional drive currents of up to 600-mA at voltages

from 4.5 V to 36 V. Both devices are designed to drive inductive

loads such as relays, solenoids, dc and bipolar stepping motors,

as well as other high-current/high-voltage loads in positive-supply

applications. All inputs are TTL compatible. Each output is a

complete totem-pole drive circuit, with a Darlington transistor

sink and a pseudo-Darlington source. Drivers are enabled in pairs,

with drivers 1 and 2 enabled by 1,2EN and drivers 3 and 4

enabled by 3,4EN. When an enable input is high, the associated

drivers are enabled and their outputs are active and in phase with

their inputs. When the enable input is low, those drivers are

disabled and their outputs are off and in


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7805 IC

It converts 12 v to 5 v in order to protect the circuit in situations

of over current over voltage conditions. This is used for

protection.

FEATURES

1. Internal Thermal Overload Protection.

2. Internal Short Circuit Current Limiting.

3. Satisfies IEC-65 Specification.

4. Package is TO-220AB

5. Output current in excess of 1A

6. Internal thermal overload protection

7. No external components required

8. Output transistor safe area protection


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9. Internal short circuit current limit

10. Available in the aluminum TO-3 package

ITEM OUTPUT VOLTAGE UNIT

KIA7805AP 5 VKIA7806AP 6 VKIA7807AP 7 VKIA7808AP 8 VKIA7809AP 9 VKIA7810AP 10 VKIA7812AP 12 VKIA7815AP 15 VKIA7818AP 18 V

KIA7820AP 20 VKIA7824AP 24 V

General Description

The LM78XX series of three terminal regulators is available with

several fixed output voltages making them useful in a wide range

of applications. One of these is local on card regulation,

eliminating the distribution problems associated with single point

regulation. The voltages available allow these regulators to be

used in logic systems, instrumentation, HiFi, and other solid state

electronic equipment. Although designed primarily as fixed

voltage regulators these devices can be used with external

components to obtain adjustable voltages and currents. The

LM78XX series is available in an aluminium TO-3 package which

will allow over 1.0A load current if adequate heat sinking is

provided. Current limiting is included to limit the peak output

current to a safe value. Safe area protection for the output

transistor is provided to limit internal power dissipation. If internal

power dissipation becomes too high for the heat sinking provided,

the thermal shutdown circuit takes over preventing the IC from


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overheating. Considerable effort was expanded to make the

LM78XX series of regulators easy to use and minimize the number

of external components. It is not necessary to bypass the output,

although this does improve transient response. Input bypassing is

needed only if the regulator is located far from the filter capacitor

of the power supply. For output voltage other than 5V, 12V and

15V the LM117 series provides an output voltage range from 1.2V

to 57V.

Voltage Range

LM7805C 5V

LM7812C 12V

LM7815C 15V

Micro-Controller


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A microcontroller is an entire computer manufactured on a single

chip Microcontrollers are usually dedicated devices embedded

within an application e.g. as engine controllers in automobiles and

as exposure and focus controllers in cameras. In order to serve

these applications, they have a high concentration of on chip

facilities such as serial ports, parallel input/output ports, timers,

counters, interrupt control, analog-to-digital converters, random

access memory, read only memory, etc. The I/O, memory, and on-

chip peripherals of a microcontroller are selected depending on

the specifics of the target application. Since microcontrollers are

powerful digital processors, the degree of control and

programmability they provide significantly enhances the

effective-ness of the application. Embedded control applications

also distinguish the microcontroller from its relative, the general-

purpose microprocessor. Embedded systems often require real-

time operation and multitasking capabilities. Real-time operation

refers to the fact that the embedded controller must be able to

receive and process the signals from its environment as they are

received. Multitasking is the capability to perform many functions

in a simultaneous or quasi-simultaneous manner.

The various components of the MCU shown in Figure 2 are

explained below: Random Access Memory (RAM): RAM is used for

temporary storage of data during run-time. ROM: ROM is the

memory which stores the program to be executed. SFR Registers:

Special Function Registers are special elements of RAM. Program

Counter: This is the "engine" which starts the program and points

to the mem-oryaddress of the instruction to be executed.

Immediately upon its execution, value of counter increments by


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The P89V51RD2 is an 80C51 microcontroller with 64 kB Flash

and 1024 bytes of data RAM. A key feature of the P89V51RD2 is

its X2 mode option. The design engineer can choose to run the

application with the conventional 80C51 clock rate (12 clocks per

machine cycle) or select the X2 mode (6 clocks per machine

cycle) to achieve twice the throughput at the same clock

frequency. Another way to benefit from this feature is to keep the

same performance by reducing the clock frequency by half, thus

dramatically reducing the EMI. The Flash program memory

supports both parallel programming and in serial In-System

Programming (ISP). Parallel programming mode offers gang-

programming at high speed, reducing programming costs and

time to market. ISP allows a device to be reprogrammed in the

end product under software control. The capability to field/update

the application firmware makes a wide range of applications

possible.


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Features

1. 80C51 Central Processing Unit

2. 5 V Operating voltage from 0 to 40 MHz

3. 64 kB of on-chip Flash program memory with ISP (In-System

Programming)

4. IAP (In-Application Programming)


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5. Supports 12-clock (default) or 6-clock mode selection via

software or ISP

6. SPI (Serial Peripheral Interface) and enhanced UART

7. PCA (Programmable Counter Array) with PWM and

Capture/Compare functions

8. Four 8-bit I/O ports with three high-current Port 1 pins (16

mA each)

9. Three 16-bit timers/counters

10. Programmable Watchdog timer (WDT)

11. Eight interrupt sources with four priority levels

12. Second DPTR register

13. Low EMI mode (ALE inhibit)

Development of a Microcontroller Based Robotic Arm

Control Logic: As the name implies, it which supervises and

controls every aspect of operations within MCU, and it cannot be

manipulated. It comprises several parts, the most important ones

including: instructions decoder, Arithmetical Logic Unit (ALU) and

Accumulator. A/D Converter: A/D stands for analog to digital. They

convert analog signals to digital signals. I/O Ports: To be of any

practical use, microcontrollers have ports which are connected to

the pins on its case. Every pin can be designated as either input

or output to suit user's needs. Oscillator: This is the rhythm

section of the MCU. The stable pace provided by this instrument

allows harmonious and synchronous functioning of all other parts

of MCU. Timers: timers can be used for measuring time between

two occurrences and can also behave like a counter. The


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Watchdog Timer resets the MCU every time it overflows, and the

program execution starts anew (much as if the power had just

been turned on). Power Supply Circuit: this powers the MCU.

(MikroElectronika, 2004). Methodology

The method employed in designing and constructing the robotic

arm are based the operational characteristics and features of the

microcontrollers, stepper motors, the electronic circuit diagram

and most importantly the programming of the microcontroller and

stepper motors.

key features

1. Low-Cost

2. 1.5-12V operation

3. 5mA current consumption at 3V

4. 0dBm output power at 3V

5. Small size: .25 x .4

6. 4800 baud operation

Conclusion

In this paper we have interfaced the robot with different kinds of

I/O devices and our method allows for storing more programs to

enhance more functionality. From our work, we deduced that in

comparison to humans, robots can be much stronger and are

therefore able to lift heavier weights and exert larger forces. They

can be very precise in their movements, reduce labor costs,

improve working conditions, reduce material wastage and

improve product quality (Mair 1988). This is why theyre very


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important in industries because the overall objective of industrial

engineering is productivity.

Selection of material for structure

For making any machine, materials used play very important role

because the strength and the rigidity of the structure depends on

the type of material used. There are many properties of material

which affect the working of the material like strength, rigidity,

vibration, damping etc. Basically, there are three materials used

for the structure which are aluminium

HARDWARE

Our choice of robotic arm is another commercially available

wheelchair mounted robotic arm the Manus Assistive Robotic

Manipulator (ARM), manufactured by exact dynamics [5]. The

Manus ARM has a two-fingered gripper end-effecter and is a

6+2DoF unit with encoders on its joints. A user may manually

control the Manus ARM by accessing menus via standard accessdevices, such as a keypad, a joystick, or a single switch. The Joint

menu mode allows the user to manipulate the Manus ARM by

moving its joints individually. The Cartesian menu mode allows

the user to move the gripper of the Manus ARM linearly through

the 3D xyz plane. In Cartesian mode, multiple joints may move

simultaneously in pre planned trajectories unlike the Joint mode.

In addition to manual control, the Manus ARM can be controlled


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by communication from a PC, and thus is programmable. As with

manual control, joints may move collaterally in Cartesian mode or

individually in Joint mode.

Aluminium

Pure aluminium is a silvery-white metal with many desirable

characteristics. It is light, non toxic (as the metal), nonmagnetic

and non sparking. It is decorative. It is easily formed, machined,

and cast. Alloys with small amounts of copper, magnesium,

silicon, manganese, and other elements have very useful

properties. Strength depends on purity. 99.996 per cent pure

aluminium has a tensile strength of about 49 mega Pascals

(MPa), rising to 700 MPa following alloying and suitable heat

treatment. Although not found free in nature,


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Aluminium

Aluminium flat strip


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Aluminium pipe

Aluminium is an abundant element in the earth's crust. A key

property is low density. Aluminium is only one-third the weight of

steel. Aluminium and most of its alloys are highly resistant to

most forms of corrosion. The metal's natural coating of aluminium

oxide provides a highly effective barrier to the ravages of air,

temperature, moisture and chemical attack. Aluminium is a

superb conductor of electricity. This property allied with other

intrinsic qualities has ensured the replacement of copper by

aluminium in many situations. Aluminium is non-magnetic and

non-combustible, properties invaluable in advanced industries

such as electronics or in offshore structures. Aluminium is non-


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toxic and impervious, qualities that have established its use in the

food and Packaging industries since the earliest times. Other

valuable properties include high reflectivity, heat barrier

properties and heat conduction. The metal is malleable and easily

worked by the common

Manufacturing and shaping processes.

SCREWS

Screw are used for making joint to one and another pieces of

aluminium sheet or any materials


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GRIPPER

We plan to use a different kind gripper that looks more appealing

with a motor and gearing system built right into the gripper

assembly. Allowing an automated open/close feature.


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MECHANICAL OPERATION OF ROBOT

1. The arm is having three joints same as human arm (wrist

movement, elbow movement, shoulder movement)

2. We have four switches to control the position of the arm. Along

with one supply on / off switch. Initially we will assume the rest

position of entire system, i.e. state when no object is placed.

3. Each control switch is having two functions. If it is operated in

one direction arm will move in one direction and vice versa.

4. Each movement is controlled with a motor through switch.

5. Motors are being supplied with two heavy duty batteries.


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6. For understanding operation, let us rename the two motors

used here. Let the name motor be M1, Now as object is placed,

control switch sw1 is operated to control the motor in one

direction it moves motor M1 in say clockwise direction due to

which whole arm moves towards picking platform. As it reaches

there, sw1 operating has to be stopped and now the same sw1 is

operated in anti-clockwise direction to hold the object by closing

jaw.

7. In the same way the other three control switches are being

operated to control the motor speed and arm position.

MOUTED TO THE CAR

By designing a mounting the system for the robotic car. we will

able to mount the robotic arm to a child-size robotic car for the

first time.


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Application

Industrial automated equipment carriers

Automated parcel carry robot

Second wave robotic reconnaissance operations


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Robotic Arm ,,Bk

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