Line Follower ROBOT
Plermjai Inchuay,
Award winner from VingPeaw Competition 2543(2000), the line follower robot built with AT89C2051, L293D, and four IR sensors. Simple circuit and platform, quick tracking and easy-understand program using C language.

I designed my Robot, which use two motors control  rear wheels and the single front wheel is free. It has 4-infrared sensors on the bottom for detecting theblack tracking tape, when the sensors detected black color, output of  comparator, LM324 is low logic and the other the output is high.

Microcontrollor AT89C2051 and H-Bridge driver L293D were used  to control direction and speed of motor.

Fig 1. Circuit diagram of my Robot.

Fig 2. Circuit diagram of Infrared sensors and comparators.

Fig 4.  Position of sensors,  left hand side is side view and right hand side is top view.


The firmware for programming the microcontroller chip is robot1.hex It was written with c language. The source code is robot1.c The c compiler is Micro-C for 8051 using TINY memory model. Here is my start up code robot.asm .

MPEG files

VIDEO sample for competition between my robot and 68HC11. VingPeaw is running by hitting the back of other.

  • movie1.mpg (1,303kB)
  • movie2.mpg (373kB)

  • December 2000

    Recovered December 2015