Simplest Line Follower Robot




a few days ago, i saw a robot at...

to be honest, the circuitry was a mess to see, although the schematic was simple, so i made a new PCB of it, and redesigned a little things, to get a very neat and small circuit of it....

this circuit needs:-

1.LM358 op-amp chip
2. 220 ohm resistors  x  4
3. 1k resistor    x  2
4. BC547B transistor (NPN)  x  2
5. white LED    x  2
6. orange LED   x  2
7. 3 or 6V DC geared motors  x  2
8. copper clad circuit board or protoboard
9. 20k pot   x  2
10.5k pot   x  2
11. photo-diode   x  2
12. 9v battery
13. 100uf capacitor

i have given the circuit design [an eagle file], for making the PCB, you can adjust the space between the sensors in the design as per your requirment...

my robot's body is not so good, but it can work on any body, its is a very easy project to make... although it needs a little adjustments in the potentiometers, the first time... enjoy... :)

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    11 Discussions


    4 years ago on Introduction

    i love robotics and i want its pcb are you able to send me this By Post
    see i live in uttrakhand and nothing available here
    the money will be deposited in your account before your posting
    also its parts
    you can contact me

    my mb. no. is

    3 replies

    Reply 4 years ago on Introduction

    you should try to make your own pcb at home, there are methods by which you can do it, i have made it at home itself...

    u can get all the components online except its pcb, there are many sites which will make this pcb if you give them this design file...


    Reply 4 years ago

    it is not work please give me solution .?


    Reply 3 years ago

    sorry for not replying, actually you must have the Photodiode and the LED parallel to each other, see any normal line follower design, plus your leds and photodiode will be attached on the other side of the board


    4 years ago

    hi I make it but it is not work always left motor is rotating please give me solution ..


    4 years ago on Introduction

    Hi. Can we ask for the C code for this project? Thanks. I look forward on your response.

    very good is more easy whith dlr than photo diode and a little cheaper thanks i'll make some for artistic proyects i dont know very much ekectronic and i hand made the electronic base but in the end all work very thanks


    6 years ago on Introduction

    yeah you can use LDR also.... :)
    and LDRs dont even have polarity too... unlike photodiodes :)