Project on line follower robot in visual basic
In this article i will provide you the programming of simple line follower robot. A line follower robot is an autonomous robot which follows black line on its own.It uses ATMEGA 16 microcontroller which take decision for the robot
Introduction to Line follower robot
Line follower robot is an autonomous robot that means it will follow the black line on its own without any control of the user. The kit i am using consist of two geared motors,a castor wheel,one ATMEGA 16 microcontroller,LCD display and three LDR sensors. LDR sensor are placed on left,center and right in front of the robot so that they will provide input to the microcontroller. Microcontroller will give instruction to the robot according to the program burned on it.Logic used for programming
We are using LDR sensors because they will give different value for the different intensity of light that is reflected back by the colour of the surface on which the robot is placed. So the sensor will provide different values for black colour and white colour. Using these value we will be detecting the black line. Lets assume 1000 is value given when sensor is placed over black and 500 when placed over white. We first take mean for both values yht comes out to be 750. Mean is taken beacuse sensor will not give same value each time even if we place it on the same surface . So a range is taken that if the value is above 750 than it is on black and if below 750 it is on white surface.So this the method to detect the line by sensorsMotion of robot according to sensor positions
There will be many conditions that may occur like forward, right turn,left turn and turn can be sharp or slant.So we have to take every situation while programing.
1.When the center sensor is on the black and other two are on white than robot should go straight.
2.When left sensor is on black and other two are on white than robot has two take a slant left turn.
3.When the right sensor is on black and others are on white than robot has to take a slant right turn.
4.When the left and center sensors are on black and other on white than the robot has to take sharp left turn.
5.When the right and center sensors are on black and other on white than the robot has to take sharp right turn.
6.When all the sensors are on white than the robot should stop.CODING
The coding is given below
$regfile = "m16def.dat"
$crystal = 1000000
Config Lcd = 16 * 2
Config Lcdpin = Pin , Db4 = Portb.4 , Db5 = Portb.5 , Db6 = Portb.6 , Db7 = Portb.7 , E = Portb.3 , Rs = Portb.2
Config Adc = Single , Prescaler = Auto , Reference = Avcc
Start Adc
Config Timer1 = Pwm , Pwm = 8 , Prescale = 1 , Compare A Pwm = Clear Down , Compare B Pwm = Clear Down
Start Timer1
Dim L As Integer , C As Integer , R As Integer
Dim Lb As Integer , Cb As Integer , Rb As Integer
Dim Lw As Integer , Cw As Integer , Rw As Integer
Dim Lbm As Integer , Lm As Integer , Cm As Integer , Rm As Integer
Cls
Lcd "place on black"
Waitms 5000
Lb = Getadc(0)
Cb = Getadc(1)
Rb = Getadc(2)
Cls
Lcd "place on white"
Waitms 5000
Lw = Getadc(0)
Cw = Getadc(1)
Rw = Getadc(2)
Lm = Lb + Lw
Lm = Lm / 2
Cm = Cb + Cw
Cm = Cm / 2
Rm = Rb + Rw
Rm = Rm / 2
Do
Cls
L = Getadc(0)
C = Getadc(1)
R = Getadc(2)
If L < Lm And C > Cm And R < Rm Then
Lcd "forward"
Pwm1b = 200
Portd.3 = 0
Pwm1a = 200
Portd.6 = 0
Elseif L > Lm And C < Cm And R < Rm Then
Lcd "Slant left turn"
Pwm1b = 70
Portd.3 = 0
Pwm1a = 170
Portd.6 = 0
Elseif L < Lm And C < Cm And R > Rm Then
Lcd "Slant right turn"
Pwm1b = 170
Portd.3 = 0
Pwm1a = 70
Portd.6 = 0
Elseif L > Lm And C > Cm And R < Rm Then
Lcd "Sharp left turn"
Pwm1b = 0
Portd.3 = 0
Pwm1a = 170
Portd.6 = 0
Elseif L < Lm And C > Cm And R > Rm Then
Lcd "Sharp right turn"
Pwm1b = 170
Portd.3 = 0
Pwm1a = 0
Portd.6 = 0
Elseif L < Lm And C < Cm And R < Rm Then
Lcd "Stop"
Pwm1b = 0
Portd.3 = 0
Pwm1a = 0
Portd.6 = 0
End If
Loop
End
Thanks Tousif. About compiler if you are making the program in visual basic than BASCOM-AVR and if embedded C than AVR-Studio.
I used AVR DUDE in order to burn the hex file on the microcontroller