Line Follower Robot Without Using Ardiuno

Line Follower Robot Without Using Ardiuno

                    Check out for full tutorial video on YouTube -                      

It is a machine that follows a line, either a black line on white surface or vise-versa. For Beginners it is usually their first robot to play with. In the following steps you will completely understand the concept of line follower.

Now we are going to build a line follower which will follow black line on a white surface, we will be using two IR sensor pair which will have an IR LED and Photo diode.

COMPONENTS REQUIRED

1) IC7805 Voltage Regulator - 1

2) L293D Motor Driver - 1

3) IR LED pair - 2

4) 300-500rpm DC Motor - 2

5) Battery 9v-12v - 1

6) Breadboard - 1

7) Chasis - 1

8) Castor wheel - 1

9) Wheels - 2

WORKING OF IR SENSOR

Generally IR rays will be reflected by white surface while black surface will absorb IR rays.In the line follower that we are going to build, both the IR sensors will be on the white surface . IR rays will be emitted and reflected back which will be detected by the Photo diode, in this state the IR sensor will send a HIGH digital signal ("1"). similarly when the sensor is on a black surface IR rays will be emitted and will not be reflected back which will be absorbed by the black surface, in this state the IR sensor will send LOW digital signal ("0"). Thus with these digital values 1 and 0 we can easily identify the state of the sensors.

Working Of Motor

We will be using two Motors of 500rpm DC motors here, you can use any motors with different rpm as per your requirement. These motors will work when they are connected to any DC power source and the direction of rotation of the motor can be changed by changing the polarity of the source.

IC L293D will be used to control the motors which will work with digital      I/O. Assume that the input given to the two motor through L293D is :-

Signal from Left IR Sensor	Signal from Right IR Sensor	Voltage Supply to Left Motor	Voltage Supply to right Motor	Turn made by the bot
1(High)	0(Low)	1(High)	0(Low)	RIGHT TURN
0(Low)	1(High)	0(Low)	1(High)	LEFT TURN
1(High)	1(High)	1(High)	1(High)	STRAIGHT
0(Low)	0(Low)	0(Low)	0(Low)	STOP

Circuit Connections

So for first place the IC on the bread board short the pin number 1 & 16 then connect it to the Vcc of both the sensor. Connect pin number 2 to Digital o/p of the LEFT sensor and pin number 15 to the  Digital o/p of the RIGHT sensor. Connect pin number 3 & 6 to the LEFT motor and pin number 11 & 14 to the RIGHT motor. Connect Ground pins of the IR sensor to pin number 4 for the LEFT sensor and pin number 13 to RIGHT sensor. Now short pin number 4,5,13,12 & Base of transistor 7805 and connect to Ground of the Battery. Now short pin number 7,8,9,10 & 16 and connect it to the Collector of the Transistor. Connect the Emitter of transistor to one end of the switch and other end of the switch to Positive of the Battery. so we are done with the circuit now place all the components on the Chasis. And thats it your robo is ready to follow the line.

CIRCUIT DIAGRAM