Major

“Obstacle Avoiding Robot”Submitted in fulfillment of PROJECT required for the

Bachelor of Engineering (B.E)

In

Information Technology

By

Sachin Narang(ue6858),Shikhar Misra(ue6878)IT 8th Semester Panjab University

Under the SupervisionOf

Ms. Inderdeep AulakhAssociate Professor, UIET

Obstacle Avoidance Robot Page 1

CONTENTS

S.No Topic Page No.

1 Cover Page 1

2 Contents 2

3 Acknowledgment 3

4 Declaration 4

5 Certificate 5

4 Abstract 6

5 Project Description 7

6 Component Description 8

7 Block Diagram & Circuit Diagram 16

8 Software Used 19

9 Algorithms 23

10 Program 24

11 Cost Of Components 26

12 Conclusion 27

13 References 28


ACKNOWLEDGEMENTIn any project that calls for study of particular aspects in any field or subject,

one needs support from number of persons who directly or indirectly

contribute by way of discussion, interaction and response. It is not possible to

thank all those who have helped in this project, but we must express heartily

gratitude to few of them.

We would like to thank Mrs. INDERDEEP AULAKH who earmarked us her

precious time and guidance without which this would have been an extremely

daunting task.

Last but not least I express my gratitude to our Institution for all kind of

opportunities help and support.


DECLARATION

We hereby declare that the work which is being presented in this report on ‘Obstacle Avoiding Robot’ submitted at U.I.E.T., Panjab University is an authentic work presented by Mr. Sachin Narang (UE6858) and Shikhar Misra (UE6878) of B.E. (I.T.) 8th semester under the supervision of Ms. Inderdeep Aulakh.

Sachin Narang(UE6858)

Shikhar Misra (UE6878)


CERTIFICATE

This is to certify that Mr. Sachin Narang(UE6858) and Mr. Shikhar Misra(UE6878) B.E. (I.T.) 8th Semester have completed Major Project , in accordance with the requirement for qualifying 8th

semester, on Obstacle Avoiding Robot under the guidance of Ms. Inderdeep Aulakh.

Inderdeep Aulakh

Associate Professor

(Teacher In-Charge)


ABSTRACTWe have undertaken a project of making a microcontroller based electronic equipment that is able to detect the distance of an object placed in its line of sight (i.e. within its range of perception). It uses Infrared Rays to detect the obstacle, in which an infrared wave is sent and the reflected wave from the object is received and on the basis of infrared sensor which senses the reflected infrared ray the presence of obstacle is verified.

After the verification of the object our equipment changes its path according to the programming of microcontroller.


1. Project Description

1.1 INTRODUCTION

Obstacle Avoidance Robot using 8051 is built using infrared sensormodule. The Right module and the left module are used to detect the obstacle on the right and the left side of the device respectively. The Right and left module are connected at approximately 45 degree to the board so as to detect the obstacle on either side.

Very often obstacles avoidance tasks rely on infrared sensors where the measuring data of the sensors are first used to gain a local representation of the environment in order to afterwards control the robot accordingly. IR sensors are simple, commonly employed, and relatively low-cost sensing modalities to perform the obstacle avoidance task. Sometimes, IR sensors may be preferable to ultrasonic sensors due to their faster response time, narrower beam width, and lower cost. The intensity of the light detected depends on several parameters including the surface reflectance properties, the distance to the surface, and the relative orientation of the emitter, the detector, and the surface. These devices are inexpensive, practical, and widely available; their use has been mostly limited to detect the presence or absence of objects in the environment (proximity detection) for applications such as obstacle avoidance or counting.

1.2 MAJOR COMPONENTS USED

Philips 89V51RD2 Microcontroller with 64kB flash memory working at 11.0592MHz.

Regulated power supply: 7-15V Power indicator LED. 2 DC motors Separate ON/OFF switches for power. UART communication circuit. 2 Infrared sensors.


2. Component Description Details

2.1 P89V51RD2(Philips) Features

The P89V51RB2/RC2/RD2 is 80C51 microcontrollers with 16/32/64 kB Flash and1024 bytes of data RAM.A key feature of the P89V51RB2/RC2/RD2 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.The P89V51RB2/RC2/RD2 is also In-Application Programmable (IAP), allowing the Flash program memory to be reconfigured even while the application is running.

Features

1. 80C51 Central Processing Unit.2. 5 V Operating voltage from 0 MHz to 40 MHz3. 16/32/64 kB of on-chip Flash user code memory with ISP (In-

SystemProgramming) and IAP (In-Application Programming).

4. Supports 12-clock (default) or 6-clock mode selection via software or ISP.

5. PCA (Programmable Counter Array) with PWM and Capture/Compare functions.

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

7. Three 16-bit timers/counters.8. Eight interrupt sources with four priority levels


2.2 PIN DIAGRAM

8051 MICROCONTROLLER CONNECTIONS


POWER-ON RESET CIRCUIT

When power is applied to the device, the RST pin must be held high long enough for the oscillator to start up (usually several milliseconds for a low frequency crystal), in addition to two machine cycles for a valid power-on reset.

An example of a method to extend the RST signal is to implement a RC circuit by connecting the RST pin to VDD through a 10 F capacitor and to VSS through an 8.2KW resistor as shown in FIGURE Note that if an RC circuit is being used, provisions should be made to ensure the VDD rise time does not exceed 1 millisecond and the oscillator start-up time does not exceed 10 milliseconds.


2.3 INFRARED SENSOR

TSOP based obstacle detector / proximity sensing module

Features: Typical Maximum Range :10cm Modulated IR transmitter

Ambient light protected IR receiver

Calibration preset for range adjustment

3 pin easy interface connectors

Bus powered module

Indicator LED


2.4 BLOCK DIAGRAM


LM7805: 3-TERMINAL 1A POSITIVE VOLTAGE REGULATORS

The LM7805 is a three-terminal positive regulator available in the TO-220/D-PAK package. It is useful in a wide range of applications. Each type employs internal current limiting, thermal shut-down and safe area protection, making it essentially indestructible. If adequate heat sinking is provided, it can deliver over 1A output current. Although designed primarily as fixed voltage

Regulators, these devices can be used with external components to obtain adjustable voltages and currents.

Pin out:

2.5 MOTOR DRIVER IC L293D


DESCRIPTION

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 (such as relays solenoids, DC and stepping motors) 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 motor supply voltage can go up to 24Volts safely. But the IC supports a maximum of only 600mA current/channel; which is more than enough to drive small DC geared motors. We use 0.22uF capacitors across both the motors to reduce the effect of noise on the circuitry. It is also recommended to add 100uF capacitor between the motor supply pin and the Gnd. Connections M1-A and M2-B correspond to Motor 1 while connections M2-A and M2-B correspond to Motor 2.

PIN CONNECTIONS

MOTOR DRIVER INTERFACING WITH MICROCONTROLLER


CONTROLLING DC MOTOR USING IC LD293D

Controlling a DC motor is nothing but controlling the direction and speed of a motor. It is very necessary to go through motor controlling concept, if you are designing an autonomous robot.

How DC Motor works ???

Let’s start with how actually DC motor runs. Direction control of a DC motor is very simple, just reverse the polarity, means every DC motor has two terminals out. When we apply DC voltage with proper current to a motor, it rotates in a particular direction but when we reverse the connection of voltage between two terminals, motor rotates in another direction.


Now let us consider how to control motor using Microcontroller provided:

1. Microcontroller provides us only digital logic (1 or a 0).2. We can’t provide polarity from microcontroller.3. We can’t connect motors to Controller as mostly motors runs on voltage higher that +5V, and motors demands high current (depends).Now the solution to above limitations is use of an “H Bridge”.It is a circuit which allows motor rotation in both directions. From four terminals of H Bridge you can control a DC motor.

It is a circuit which allows motor rotation in both directions. From four terminals of H Bridge you can control a DC motor.

Motors can be driven in clockwise direction or anti-clockwise direction according to our requirements. To do so we first need to connect motors and find out the commands we need to give to our microcontroller to perform the specific rotation.

3. Circuit Basic Block Diagram & Circuit Diagram


LS

FS8051µC

Memory

ML

Circuit Diagram

4. Software Used

A) TRIC: FOR PROGRAMMING MICROCONTROLLER USING C.

B) FLASH MAGIC: FOR BURNING PROGRAM.


RS Clock

MR

4.1TRIC:

Library files used:

1 DC MOTORS:

A. RUNMOTOR (motor number, direction, speed) This is the prototype of function RUNMOTOR used to move

the motor in a specified direction, with desired speed. Once you make a call to this function it keeps running the motor unless you call another function STOPMOTOR discussed next.

motor_num :-As we know that to the iBOT we can connect four dc motors at a time, the first thing we need to mention is the motor which we want to know the motor_num accepts the values to specify the motor number to be moved which are motor1 (PORT P2_0 and P2_1), motor2 (PORT P2_2 and P2_3), motor3 (PORT P2_4 and P2_5), and motor4 (PORT P2_6 and P2_7). Any other values apart from this will not give the desired results.

Direction :-Next is the direction in which we want to rotate the motor either clockwise or anticlockwise, note this direction is with respect to the shaft of the motor while looking into the shaft. Thus if you want to rotate the motor clockwise for a while you have to input the direction as cw and ccw, if in case you want it to rotate in anticlockwise rotation

A point to ponder is that when you rotate a wheel clockwise it tries to move the vehicle forward whereas the other side-wheel will tend to move the vehicle backward and as such the vehicle will revolve around at its position. Thus you have to run the other motor in anticlockwise direction, so that the vehicle moves forward as such. This seems a bit confusing is it? And also a tedious thing to do. Hence to make things simpler what you can do is that connect the motors one side of vehicle in reverse order the way you connect the other. Thus clockwise may be the direction to move the vehicle forward and anticlockwise to both to move the vehicle back.

Speed: - Generally, the rotational speed of a DC motor is proportional to the voltage applied to it. So the parameter is percentage of the maximum speed with which the motor can be rotated. Thus the speed value varies from 0 to 100.

B. STOPMOTOR (motor_num) This is the prototype of the function called STOPMOTOR used to stop the respective motor passed as parameter to this function. There is one and only parameter motor_num which mention the motor number to be stopped.


2. DELAY

DELAY ( unsigned int time) This function is used to generate the real time delay in

milliseconds it has only one parameter time which accepts the integer values in the range of 0 to 65535 thus it can generate a time delay of 0 milliseconds to 65535 milliseconds. If the user has a need of higher delays then he has to call the function DELAY multiple times to meet his requirements.

EXAMPLE:

#include<delay.h>void main ()

while (1)

P3_1=~P3_1;DELAY (100);

In the above program the function DELAY (100) generates a delay of 100 milliseconds and thus toggles the pin1 of port 3 every 100 milliseconds infact in other ways it generates a square wave of 20 Hz frequency.


4.2 FLASH MAGIC

Flash Magic is Windows software from the Embedded Systems Academy that allows easyAccess to all the ISP features provided by the devices. These features include:• Erasing the Flash memory (individual blocks or the whole device)• Programming the Flash memory• Modifying the Boot Vector and Status Byte• Reading Flash memory

The window is divided up into five sections. Work your way from section 1 to section 5 to program a device using the most common functions. Each section is described in detail in the following sections.At the very bottom left of the window is an area where progress messages will be displayed and at the very bottom right is where the progress bar is displayed. In between the messages and the progress bar is a count of the number of times the currently selected hex file has been programmed since it was last modified or selected.


5. Algorithms for Coding

Start

If Obstacle not Present on either side (RS=FS=LS=0)

Move Forward

Else if Obstacle Present in Front but not on either side (FS=1, RS=LS=0)

Turn 45O left

Else if Obstacle Present on Right but not on front and left side (FS=0, RS=1, LS=0)

Turn 45O left

Else if Obstacle Present in Left but not on front and right side (FS=0, RS=0, LS=1)

Turn 45O right

Else if Obstacle Present in Front and Right side but not on left side (FS=1, RS=1, LS=0)

Turn 90O left

Else if Obstacle Present in Front and Left side but not on right side (FS=1, RS=0, LS=1)

Turn 90O right

Else if Obstacle Present in Front and Left side but not on right side (FS=1, RS=1, LS=1)

Turn 135O left

End


Left Sensor Right Sensor Action

1 0 45o turn right

0 1 45o turn left

1 1 90o turn left

0 0 Move forward

6. Program

include<P89V51RD2.h>

#include<delay.h>

#define fwd 0x05

#define right 0x04

#define left 0x01

void main()

P1=0xFF;

P2=0x00;

while(1)

if(P1_0==0 && P1_1==0)

P2=fwd;

DELAY(50);

if(P1_0==1 && P1_1==0)


P2=left;

DELAY(50);

if(P1_0==0 && P1_1==1)

P2=right;

DELAY(50);

if(P1_0==1 && P1_1==1)

P2=left;

DELAY(250);

P2=left;

DELAY(50);


COST OF THE COMPONENTS:

Sr.No. Name Quantity Cost in Rs.

1 P89V51RD2 1 150

2 L2933 1 100

3 ENABLE SWITCH 1 10

4 LED 1 1

5 CRYSTAL-11.0592 MHz 1 10

6 DIODE(IN4007) 1 4

7 CAPACITOR(10µF) 1 4

8 CAPACITOR(0.1pf) 5 10

9 (Voltage controller)L7805 2 14

10 Resistor(1kΩ) 1 1

11 RESISTORS(10kΩ) 1 1

12 DB9 FEMALE CONNECTOR 1 10

13 BURG STRIP – MALE 1 4

14 IC BASES-various 2 20

15 ADAPTOR(12V 1AMP) 1 125

16 BOARD 1 20


17 IR SENSORS 2 200

18 GEARED MOTORS 2 400

19 BODY - 200

20 BURNING KIT 1 1400

TOTAL COST 2700

Conclusions

As during driving there is a chance of human error which may lead to accidents. Keeping this in mind automatic systems are employed to avoid human errors and for ease of work.

Hence, we conclude that use of sensors & microcontroller in our project proves to be very helpful as these can provide better and faster results.

Innovativeness and Usefulness

1. The project promises immense benefit in engineering and design of more efficient automated control for vehicles.

2. Improved safety and better control for vehicle and robotic automation.


References

1. www.avrfreaks.net : A website with resources for AVR

microcontrollers

2. www.PHILLIPS.com : The official website of PHILLIPS Corp.

3. www. avago tech.com : The official website Avago Technologies

4. www. vishay .com : The official website of vishay Corp.

5. www.national.com : The official website of National Semiconductors

6. www.roboticsindia.com : For Indian Robotics and electronics

enthusiasts.

7. www.wikipedia.com : A website for free encyclopedia

8. www. winavr .sourceforge.net : The official website of WinAVR

software

9. www.datasheetsforyou.com : Website for datasheets


http://www.datasheetsforyou.com/

http://www.winavr.sourceforge.net/

http://www.wikipedia.com/

http://www.roboticsindia.com/

http://www.national.com/

http://www.vishay.com/

http://www.avagotech.com/

http://www.PHILLIPS.com/

http://www.avrfreaks.net/


Major

Education

turn 45o left

8th semester

left module

dc motor

vehicle forward

progress bar

machine cycle

inderdeep