BO & Gear Motors

BO motors are the small yellow DC gear motors behind most beginner robot cars. A DC motor with a gearbox trades speed for torque, so a light chassis can climb and turn on its own wheels.

Common types:

  • BO and TT motors come in straight and L-shaped versions and fit common 2WD and 4WD chassis kits.
  • 12V DC geared motors are bigger and stronger, for heavier robots and mechanisms.
  • The RPM rating tells you the trade-off: lower RPM gives more torque and slower, more controllable driving.

How to choose:

  • Pick the RPM for your robot's job: slow for line following, faster for open floors.
  • Pick the shape and mount that fit your chassis.
  • Buy matching pairs so both sides drive evenly.

A DC gear motor cannot run from an Arduino or ESP32 pin. It needs a motor driver such as an L298N, which also lets you reverse it and control speed with PWM. Power the motors from a separate battery pack, and share ground with the board.

Frequently asked questions

What is a BO motor?

A small DC motor with a plastic gearbox, used on most beginner robot cars and chassis kits.

What RPM should I choose?

Lower RPM for more torque and control, as in line followers. Higher RPM for faster driving.

Can I connect a BO motor directly to an Arduino?

No. Use a motor driver such as an L298N and a separate battery.

2WD or 4WD?

2WD is simpler and fine indoors. 4WD handles rough ground better and needs drivers for four motors.

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