"DIY - THE EXCELLENT LINE TRACER ROBOT WITHOUT MICROCONTROLLER"

Hi
I am Ajinkya Dixit
this is my first robotics project - " THE LINE TRACER ROBOT WITHOUT MICROCONTROLLER "
These robot contains no any kind of microcontrollers , instead it uses only integrated circuit (IC) and some other electronics parts.

There is a great problem with me about microcontroller's, because of my trade (INFORMATION TECHNOLOGY). I have no any knowledge about microcontroller's but , electronics and robotics is my hobby and strength also. So to making these line follower robot i have struggled from last two months. Finally it's made!!!! . I have made these robot without anyones help and lessions about electronics and robotics.

So r u interested in making these robot ??? then see the following steps.

For this project u will need following components :
1. IC - L2963D The motor driver IC .x 1
2. LDR'S (Light Depending Resistors) x 2
3. White LED's x 2
4. Resistors 10 k x 4
Resistors 100 Ohm x 2
5. POT'S 20k x 2
6. Generel PCB'S.
7. 7-Segment displays (i have used 5 displays. It depends on what u want to display.)
8. 9 v Battery x 2
9. 3 or 6 v DC Geared Motors x 2 .
10. Some other miscellineous parts.

Also the main circuit board is my homemade PCB made out of generel purpose pcb.
to make this u will need:
1.A small PCB(Single sided).
2.Laser printer(only laser printer is better) & OHP sheet.
3.FeCl3(Ferrus Cloride) PCB Etching Solution.
4.Cloths iron.

Gathered Parts Together?
Ready?
ok.......
See next step....

Now Look carefully following circuit Diagram & try out the circuit on bread board first.
if it is working properly go to making its PCB version. the PCB for the project is homemade PCB that is
shown here.
These Line Tracer Robot uses the main part which is the populer IC chip -IC L293D the motor driver IC / H - BRIDGE IC!!!
The schematic shows the pin - to - pin connections of L293D!!!

I have implemented these circuit on the breadboard first for confirmation and after that the final ckt is implemented on PCB.

Although these schematic shows the use of optoisolators , i have used the simple LED's (white) & LDR's as sensors.
You can use photodiodes as an alternative to LDR's but it requires change in it's sensing frequency due to difference between rate of light absorbed by it in day and night. (CNY70 IS VERY BEST OVER ALL OF THESE).

The value of POT depends on u r choice but in between range of sensors frequency.

To making LINE FOLLOWER ROBOTS i have tried lots variety of motors like toy motor, DVD player motor, tape recorder motor,
and so on. But finally i understood that these motors does not work for these robot.
Hence I have used the 12 v DC Geared motors having 150 RPM.
U can use 3 or 6 v DC Geared motors also.

NOTE: The PCB & whole description is now easily available online. Please go thru the link :http://electronicsforu.com/diy/hardware-diy/simple-line-following-robot