100 RPM L-Shape Single Shaft BO Geared DC Motor – 3V–12V Battery Operated Robot Motor

100 RPM L-Shape Single Shaft BO Geared DC Motor – Battery Operated Robot Motor (3V–12V)

The 100 RPM L-Shape BO Geared DC Motor (MTR-QC0301) is one of the most widely used DC gear motors for robotics and embedded systems prototyping. Its compact L-shaped plastic gearbox design, wide operating voltage range of 3V to 12V DC, and low-cost rugged construction make it the go-to actuator for students, hobbyists, and makers building line follower robots, obstacle avoider robots, and DIY robot car chassis.

While it does not deliver high torque or ultra-high RPM, it reliably gets the job done for lightweight robot platforms. It supports bidirectional rotation — simply reverse the polarity of the supply to reverse the direction of rotation. Two integrated screw holes on the motor body allow for straightforward and secure mounting to standard robot chassis frames.

Key Features

• Rated Speed: 100 RPM (after gear reduction)
• Operating Voltage: 3V – 12V DC (wide range)
• Rated Torque: 0.35 kg-cm
• No-Load Current: 40mA – 180mA
• Low Weight & Low Inertia — responsive acceleration
• Low Coefficient of Friction — smooth gear operation
• Bidirectional Rotation — reverse polarity to reverse direction
• 2 Screw Mounting Holes — easy chassis integration
• Rugged & Low Cost — ideal for prototyping and educational use

Technical Specifications

Compatible Motor Drivers

Compatible Platforms

• Arduino Uno, Nano, Mega (via motor driver module)
• Raspberry Pi (via motor driver HAT or L298N)
• ESP32 DevKit (via motor driver — never drive directly from GPIO)
• ESP8266 NodeMCU (via motor driver)
• STM32, Teensy (via motor driver)

How to Use

Connect this motor via a compatible motor driver such as the L293D or L298N. Route the motor driver output wires to DC Terminal 1 and 2 of this motor. Attach the mechanical output shaft to your robot wheel or robotic arm. Control direction and speed using PWM signals from your microcontroller to the motor driver's input and enable pins.

Arduino Sample Code (L298N)

#define IN1 7    // Motor direction pin 1
#define IN2 8    // Motor direction pin 2
#define ENA 9    // PWM speed control (Enable A)

void setup() {
  pinMode(IN1, OUTPUT);
  pinMode(IN2, OUTPUT);
  pinMode(ENA, OUTPUT);
}

void loop() {
  // Forward at 70% speed
  digitalWrite(IN1, HIGH);
  digitalWrite(IN2, LOW);
  analogWrite(ENA, 178);   // 0–255 = 0–100% speed
  delay(2000);

  // Reverse at 70% speed
  digitalWrite(IN1, LOW);
  digitalWrite(IN2, HIGH);
  analogWrite(ENA, 178);
  delay(2000);

  // Stop
  digitalWrite(IN1, LOW);
  digitalWrite(IN2, LOW);
  delay(1000);
}

Applications

• Line Follower Robot — differential speed control for precise path tracking
• Obstacle Avoider Robot — forward/reverse drive with ultrasonic sensor (HC-SR04)
• 2WD / 4WD Robot Car Chassis — standard drive wheel motor
• Bluetooth / Wi-Fi Controlled Robot — remote-controlled via HC-05 or ESP32
• Firefighting Robot — chassis drive motor (see Arduino Firefighting Robot guide)
• Educational Robotics — STEM kits, school science projects, Arduino labs
• DIY Automation — slow-speed mechanical actuators, turntables, feeders

Important Usage Notes

• Never connect directly to GPIO: Always use a motor driver — GPIO pins cannot supply the required current.
• Separate power supply: Power the motor from a dedicated battery pack — do NOT draw from Arduino 5V/3.3V pins.
• Back-EMF protection: Use motor driver modules with built-in flyback diodes to protect your microcontroller.
• PWM Speed Control: Apply PWM via motor driver ENA/ENB pins for variable speed.
• Direction Control: Reverse supply polarity (via motor driver IN pins) to reverse rotation.

Additional Resources

• Arduino Based Firefighting Robot – Project Guide
• Compatible with motors from our Motor Drivers Collection (L298N, L293D, BTS7960)

Package Contents

• 1 × 100 RPM L-Shape Single Shaft BO Geared DC Motor