Build a No-Code Line Follower Robot Using Havi Elements

Introduction

For many robotics enthusiasts, a line follower robot is the first project that feels truly autonomous. Watching a robot sense its environment and make decisions in real time is often the moment when electronics transforms from theory into something exciting and tangible.

Most line follower tutorials require a microcontroller, programming, and electronic circuit assembly. In this project, we build a simple line follower robot using Havi Elements, without any coding, microcontroller or soldering. This makes it suitable for beginners, kids, students, STEM workshops, and anyone taking their first steps into robotics.

The robot uses an Infrared (IR) sensor to detect a black path on the floor and automatically steer itself along the route.

How Does a Line Follower Robot Work?

A line follower robot follows a predefined path drawn on the floor. The path is usually a black line on a light colored surface.

The sensor on the robot continuously checks whether it’s positioned over the black line or over the surrounding floor. Based on this information, the robot changes which motor is running, causing the robot to turn left or right and stay on the track.

Line following is a fundamental robotics concept and is often used as an introduction to

• Sensors
• Autonomous navigation
• Logic circuits
• Industrial automation
• Mobile robotics

Building the Robot

Step 1: Create the Track

Create a path on the floor using black electrical tape. A light-colored floor works best because it provides strong contrast for the IR sensor.

The line should be wide enough for the sensor to detect consistently during turns.

Step 2: Assemble the Robot Base

Build a simple two-wheel robot chassis using the geared motors, wheels, roller wheel, and base plate. You can use either double sided tape or wire ties to keep the hardware parts together.

The robot should move freely and maintain good balance.

Step 3: Mount the Havi Elements Circuit

Assemble the circuit using the modules listed above and attach it securely to the robot chassis.

Position the IR sensor close to the floor and facing downward so it can detect the path accurately.

Tip: Using an icecream stick (popsicle stick) will help IR Element detect the line well.

Step 4: Tune the IR Sensor

Sensor tuning is the most important part of this project.

Adjust the potentiometer on the IR sensor until it can clearly distinguish between:

• The black path
• The surrounding floor

When properly adjusted, the robot should respond only to the black line and ignore minor variations in the floor surface.

It would be interesting to observation how sensitive the robot's behaviour became to sensor placement. Even a few millimetres of height difference or distance from the chassis, changes detection accuracy noticeably.

Understanding the Science

The IR sensor contains:

• An infrared emitter
• An infrared receiver

The emitter sends infrared light toward the floor.

Light colored surfaces reflect most of this light back to the receiver.

Black surfaces absorb most of the infrared light and reflect very little.

The robot uses this difference in reflection to determine whether it is currently over the path

Steering Logic

The robot uses two motor elements controlled by the IR sensor.

When the sensor detects reflected infrared light from the floor:

• One motor runs
• The other motor stops

When the sensor moves over the black line and the reflection disappears:

• The first motor stops
• The second motor runs

Because only one side of the robot is powered at a time, the robot continuously corrects its direction and stays near the edge of the line.

This creates a simple but effective line-following behaviour without programming.

Testing the Robot

Place the robot on the track and power it on.

If the sensor is tuned correctly, the robot will continuously adjust its direction and follow the path automatically.

Try experimenting with:

• Sharp turns
• Curved paths
• Different line widths
• Different speeds

These variations help demonstrate how sensor-based navigation works.

Troubleshooting

Robot does not detect the line

• Reduce the distance between sensor and floor.
• Retune the potentiometer.
• Increase the contrast between line and floor.

Robot keeps turning in one direction

• Verify motor connections.
• Check sensor alignment.

Robot works indoors but not outdoors

Infrared sensors can be affected by sunlight. Direct sunlight contains infrared radiation that may interfere with sensor readings.

For best performance, test the robot indoors or away from strong sunlight.

Real-World Applications

Line follower robots are used in many real-world automation systems:

• Material transport in factories
• Warehouse logistics
• Hospital delivery robots
• Restaurant service robots
• Educational robotics platforms

Although this project is simple, it introduces the same sensing principles used in larger autonomous systems.

Conclusion

This project demonstrates how autonomous navigation can be achieved using a simple IR sensor and modular electronics.

By building this no-code line follower robot, beginners can learn the fundamentals of sensing, decision-making, and robotic movement without the complexity of programming or soldering.

It is an excellent project for students, makers, STEM clubs, classrooms, and robotics workshops.