Users Manual

CLASS 4
100
A differential gear unit is a device that is used to transmit moving forces in real cars. So far you've created robots
that use two wheels to move around. All the robots that use two wheels use two DC motors. I put the wheels on
each DC motor one by one, and I made the robot to operate two wheels.
However, with a differential gear unit, not only can one DC motor deliver the power of movement to both wheels,
but also the power delivered to each wheel can be different! Therefore, even when the floor is uneven, the two
wheels can work differently and work smoothly.
When two DC motors are used, the power to turn the wheels per DC motor is fixed by a constant force, so it is
possible to move forward in a flat place, but in a rugged position, it cannot move forward.
If you use two DC motors as shown in the picture above, the two wheels always rotate with the same force, so
you cannot go straight to the rugged place.
However, using a differential gear system gives the wheels on the side with the obstacles more power so the car
can go straight! These differential gears are essential for making autonomous vehicles and can be a basic factor.
Differential gear unit
Concept