FIU – UPC Cooperation Agreement
Projects developed by UPC students
Course: Digital Logic Circuits
Level: Fourth semester
Logic control system of a line-follower robot.
Design and construct the logic control system of a line-follower mobile robot using only
discrete digital components. The robot should autonomously follow a white line and analyze
path bifurcations to achieve the final goal position as it is shown in Fig. 1.
Teamwork: 4 students
Note: The teamwork is provided with the complete mechanical structure and will focus on
the design of the digital logic control system including sensors, batteries and ON-OFF power
Path to follow
Figure 1. Path with bifurcations.
• The robot should detect the white line using three light sensors.
• The line width is 1 inch.
• There are only two bifurcations.
• When detecting the first bifurcation the robot should take the left path.
• When detecting the second bifurcation the robot should take the right path.
• The robot is equipped with two DC motors for traction. By properly activating the
motors, the robot can move forwards, backwards, as well as turns left or right.
The general structure of the mobile robot is shown in Fig. 2.
Project developments and analysis:
After several running tests, it was found that one step of motion should be less than 5
millimeters in order to avoid slipping and skidding.
Figure 2. Robot general structure.
Digital Logic System
By analyzing the robot motion and path geometrical characteristics, the logic of the motion
control system was determined to be as it shown in Table 1:
Table 1: Logic of moti