The aim of this project is to build an autonomous mobile robotic vehicle, controlled by a microcontroller chip to follow lines as accurate and fast as possible. The robot should follow a black line drawn on a white (or light colored) floor, and the line could be straight, or it may have curvatures or sharp angles, as well as, line breaks. A mechanical model of a three-wheel vehicle with two-motor differential steering method has been constructed, with a set of infrared sensors mounted at the front of the vehicle to see its route. The appropriate electronic circuit board has been implemented based on the ATMEL 89C2051 microcontroller chip that takes the converted digital readings from the sensors and controls the direction and movement of the robot using pulse width modulation (PWM) to drive the motors. A control software algorithm has been developed and compiled into a HEX file that eventually had been written to the Microcontroller through the PC serial port. Adjustments have been done through iterative steps, and development levels were demonstrated in the form of four case studies, to come to the final result of the robot system by applying each model to different types of line shapes. The main adapted design feature was the number of sensors and the control software. At first, two sensors with a very simple algorithm had been observed, then going up to the final model that uses a set of 6 sensors and an advanced multi-condition handling algorithm which qualifies it to run smoothly and efficiently. As well as, this model had been also developed to handle breaks in the line continuity or try to search for the line in case it was lost, and also make 90 degree sharp turns at cornered shape paths.