Hi friend …!! Welcome back…! this time I am here with a very
interesting project for robotics beginners, in this tutorial I am going to
discuss how to make an autonomous line follower robot without using a
microcontroller, so lets have a look how to make your own autonomous robot with
intelligence of following a black line on white surface or white line on black
surface.
INTRODUCTION
Line followers are the autonomous robots with the capability
of following a black line on white surface and vice versa. Basically we use
some kind of sensors to detect the color difference between line and surface. In
our project we are going to use IR sensors for detail description of IR sensor first
of all read this article BASIC ELECTRONICS PROJECT 6- MAKING AN IR SENSOR
According to the output of sensors we control our motor to
control the direction of robot. In this project we are going to make a BLACK
LINE FOLLOWER.
REQUIREMENTS
A robust chassis for robot
Two motors
Two wheels
One caster wheel
Two IR sensors
One motor driver IC ( we are using ULN2003A)
IC 7432
And a power supply.
STRUCTURE OF ROBOT
Attach wheels with motor to the chassis, place sensors at
front side at a distance more than width of the black line. Also attach caster
wheel at front side between sensors. Structure will look something like this-
ALGORITHM FOR LINE FOLLOWER ROBOT (USING TWO SENSORS)
-Start
-Check for line
-CASE 1-If both sensors are on move
forward
- CASE2-If only left sensor is off ,
turn left till both sensors are on
the line
-CASE 3-If only right
sensor is off, turn right till both sensors are on the line
These three cases are illustrated in this figure-
These three cases are illustrated in this figure-
ELECTRONIC
CONNECTIONS
Now just connect sensors, ICs and motors as shown in the
diagram below-
So now our first line follower robot is in action.
In case of any doubt, query or critical view just leave a
comment. I am waiting for your comments.
THNX..:)
What is the function of ULN2003A ?
ReplyDeleteTell me another IC to replace this 2003A IC .
Hi.. Mak ......ULN2003 is a high voltage and high current Darlington array IC. It contains seven open collector darlington pairs with common emitters.And a darlington pair is used to maximizing current gain, so we are using this IC as a motor driver here. you can replace this IC by any other IC of ULN200X family or any other motor driver like L293D, L298 etc. Moreover if you do not want to use any IC you can use simply transistors to make a darlington pair for maximizing current gain .To know more about darlington pair read my post on TRANSISTORS in ELECTRONICS TUTORIAL section. (link http://abhitechstrong.blogspot.in/2012/11/basic-electronics-tutorial3-transistors_30.html
ReplyDeletewhere is microcontroler??
ReplyDelete@SACHIN......ithnk u hv nt read the title of article......its without using microcontroller....:)
Deletesir how much supply is sufficient for the bot n how much rpm motor is good to use....n pls clr me tat 2nd terminal of motor is connected to which pin n also which type of sensor should i use
ReplyDelete@Garvit......i will suggest you to use 9v DC, and 100 rpm motor,......n second terminal of motor is connected to Vcc means positive of your power supply....:)
Deleteand u have to use Infra red sensor as i hv told in this tutorial.
Deletehi iam balaram i didn't understand that how to connect ir sensor with circuit board
ReplyDeletehow to connet ir sensor with this circuit board
ReplyDeletehi, Balram
Deleteu cn see that ur ir sensor is having 3 pins 1 for vcc, 1 for GND and 1 output, you have to connect vcc and GND of both the sensors to VCC and GND as given by power supply and outputs to the 1st and 5th pin of IC7432 respectively.......:)
what if i use LDR and LED for sensor part of robo ??
ReplyDeleteshould i use pots ??
Hii.. Shaheryar ....... you can definitely use LDR with LEDs in place of IR sensors. and yes you will have to use pots for sensor caliberation..:)
Delete
ReplyDeletevery clean and neat explanation
great write up! thank you
Welcome....:)
Deletesir could u plz explain the circuit operation??
ReplyDeleteyes kartick of course..!!
Deleteas you u can see there are two IR sensors attached , i think you are familiar with working of ir sensor, in short its a sensor which generates a high logic when some object comes in front of it, if there is no object or any black object it generates no logic, as black absorbs all the ir rays. next thing is ORgate IC 7432 simple logic 1 OR 0=1 hence evry time sensor generates high logic this high logic is as it is passed to ULN 2003 IC , this ic is monolithic IC consists of seven NPN darlington transistor pairs with high voltage and current capability. It is commonly used for applications such as relay drivers, motor, display drivers, led lamp drivers, logic buffers, line drivers, hammer drivers and other high voltage current applications. hence for every high logic of sensor it producces a high current voltage signal which is used to drive the motor an these motor are used to drive your bot. and turn your bot accordingly as per sensor output depending on the condition of black or white surface beneath it. I hope you got my point . still there is any problem just leave a coment.
Thanks..:)
Hi,
ReplyDeletehow can it be following a white line on black surface?
Sir I WANT BREAD BOARD VERSION I AM NOT FAMILIAR BUT SMALL WITH THIS CIRCUIT IAM IN 8TH STD I LOVE TO MAKE ROBOT I TRY TO MAKE WITH TRANSISTOR BUT IT WONT WORKED PLS HELP ME
ReplyDelete