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  The Robot You Are Going To Build

In this course you are going to build a light-following robot that uses a couple of wheels to move around. This type of robot can be built in a very easy way, and it’s easy to understand how it works.

And that’s what I want for you by taking this course – not only will you be building the robot – you will also learn how all the parts of the robot works!

The light-following robot

To build your robot, you will need motors to make the robot move. You’ll need sensors that can detect light. And you will need something that can control the motors based on the amount of light that is detected.

By using two motors and two light detectors, you can make the robot go straight when the light is right in front of it, or turn to the left or right if the light is to the sides.

The robot you are going to build will consist of two DC motors. One for each wheel. This means that if both motors are on, the robot will move forward. If only the left motor is on, the robot will turn to the right. And if only the right motor is on, it will turn to the left.

To follow the light, you are going to use two light sensors. One that senses light to the right, and one to the left. Then you will combine these with some electronics, to control each of the motors.

Choosing a motor

You are going to build a robot that uses wheels for moving around. This means you need a motor that can drive the wheels. The best motor for this task is the DC motor.

The shaft of a DC motor, usually spins very fast. And that can be a problem, because you’ll end up with a robot that just spins instead of moving.

To solve this problem, you need to gear down the spinning speed of your DC motor. Here’s a video where you can see the difference between a motor with and without gears:

Some motors come with internal gears and such a motor is called a geared DC motor. And that’s the type of motor you’ll need for this project.

There are many geared motors available. I chose a pair of the DG02S Mini DC Gear Motor from DAGU ( These fit snuggly onto a pair of 65 mm wheels and have a good spinning speed for this project (65 RPM).