Line Follower Robot


In this project a line follower will be constructed. The robot will be based on a chassis kit I found on AliExpress.


I've always wanted to build a Line Follower Robot. I saw a good opportunity when I found this kit on AliExpress. It looked like a neat base for a line following robot so I didn't hesitate to order it.


I created a block diagram over the line following robot.


Here's what I received when the package arrived.

I must say I was surprised by the high quality of the robot kit. The wheels actually had rubber tires (I expected plastic tires), and the motors were very silent and didn't consume much current.

Here's a close-up of the base with attached motors.

I didn't like the included caster wheel, so I replaced it with a different one I happened to have lying around.

Here's the new caster wheel attached to the robot's base.

And here's what the robot looks like so far.

Next step is to plan where the different parts will be placed on the robot. It became quite evident that I don't have much space for all the parts.

Here's the top of the robot, with most parts attached, i.e. the microcontroller, the battery packs, fuses and a switch.

I attached the IR sensors on the front of the robot. These three sensors will make sure the robot stays on the line.

I began wiring the top of the robot. The switch is of DPDT, and therefore I can turn both the 9V battery and the 6v battery pack on/off with just 1 switch.

I attached the motor controller on the bottom of the robot, and wired it to the motors.

Here's the robot, fully assembled and ready to be programmed.

The robot is programmed in C with Atmel studio 6. I first planned on using interrupts when the line is detected, but I ended upp using polling as it was easier to implement (and probably more suitable for this robot).

The C program can be downloaded below.



last edited: 2016.04.06

Components used

Robot kit from Aliexpress

Minimum system board

AVR ATmega168 Microcontroller

L9110 H-Bridge module

DPDT Switch

9v Battery Holder

6V Battery Holder

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