Using the MPU-6050 with the Raspberry Pi

The MPU-6050 is a 6-axis motion tracking device with a gyroscope and accelerometer, making it ideal for motion-sensing applications like robotics, drones, and IoT projects. In this guide, you will learn how to connect and use the MPU-6050 with a Raspberry Pi to capture motion and orientation data.

What You Will Need

1. Raspberry Pi (any model with GPIO support, e.g., Pi 3, Pi 4)
2. MPU-6050 Module
3. Breadboard and Jumper Wires
4. A computer with SSH access to the Raspberry Pi or a connected keyboard and monitor
5. Python installed on the Raspberry Pi

Step 1: Wiring the MPU-6050 to the Raspberry Pi

The MPU-6050 communicates with the Raspberry Pi using the I2C protocol.

Connections

Note: Ensure the MPU-6050 module operates at 3.3V. Most modules include a voltage regulator, allowing them to be powered with 5V.

Step 2: Enable the I2C Interface on the Raspberry Pi

1. Open the Raspberry Pi configuration tool:

   sudo raspi-config
   

2. Navigate to Interface Options > I2C and enable it.
3. Reboot the Raspberry Pi:

   sudo reboot
   

Step 3: Install Required Tools and Libraries

1. Update your Raspberry Pi:

   sudo apt update && sudo apt upgrade -y
   

2. Install the I2C tools:

   sudo apt install -y i2c-tools
   

3. Install Python libraries for I2C communication and data processing:

   pip install smbus2
   

Step 4: Verify the Connection

1. Use i2cdetect to verify the MPU-6050 is detected on the I2C bus:

   sudo i2cdetect -y 1
   

2. You should see the MPU-6050 at address 0x68 (or 0x69 if the AD0 pin is pulled high). If not:
   • Check your wiring.
   • Ensure the MPU-6050 is powered.

Step 5: Reading Data from the MPU-6050

The following Python script reads accelerometer and gyroscope data from the MPU-6050.

Python Code Example

import smbus2
import time

# MPU-6050 Registers and Address
MPU6050_ADDR = 0x68
PWR_MGMT_1 = 0x6B
ACCEL_XOUT_H = 0x3B
GYRO_XOUT_H = 0x43

# Initialize I2C bus
bus = smbus2.SMBus(1)

# Wake up the MPU-6050
bus.write_byte_data(MPU6050_ADDR, PWR_MGMT_1, 0)

def read_raw_data(addr):
    # Read two bytes of data from the given address
    high = bus.read_byte_data(MPU6050_ADDR, addr)
    low = bus.read_byte_data(MPU6050_ADDR, addr+1)
    value = (high << 8) | low
    # Convert to signed value
    if value > 32767:
        value -= 65536
    return value

try:
    while True:
        # Read accelerometer data
        accel_x = read_raw_data(ACCEL_XOUT_H)
        accel_y = read_raw_data(ACCEL_XOUT_H + 2)
        accel_z = read_raw_data(ACCEL_XOUT_H + 4)

        # Read gyroscope data
        gyro_x = read_raw_data(GYRO_XOUT_H)
        gyro_y = read_raw_data(GYRO_XOUT_H + 2)
        gyro_z = read_raw_data(GYRO_XOUT_H + 4)

        # Convert raw data to meaningful values (optional scaling may be needed)
        accel_x_scaled = accel_x / 16384.0
        accel_y_scaled = accel_y / 16384.0
        accel_z_scaled = accel_z / 16384.0

        gyro_x_scaled = gyro_x / 131.0
        gyro_y_scaled = gyro_y / 131.0
        gyro_z_scaled = gyro_z / 131.0

        print(f"Accelerometer: X={accel_x_scaled:.2f}, Y={accel_y_scaled:.2f}, Z={accel_z_scaled:.2f}")
        print(f"Gyroscope: X={gyro_x_scaled:.2f}, Y={gyro_y_scaled:.2f}, Z={gyro_z_scaled:.2f}")

        time.sleep(1)

except KeyboardInterrupt:
    print("Exiting...")

Step 6: Applications of the MPU-6050

1. Motion Tracking: Track movement and orientation in robotics or wearables.
2. Stabilization Systems: Implement gyroscopic stabilization for drones or gimbals.
3. Gaming: Create motion-based game controllers.
4. IoT Projects: Use motion data to trigger automation events.

Troubleshooting

1. Device Not Detected:

   • Verify SDA and SCL connections.
   • Ensure the I2C interface is enabled on the Raspberry Pi.
   • Check the power supply to the MPU-6050.

2. Inaccurate Readings:

   • Calibrate the sensor by implementing an offset for each axis.
   • Ensure the sensor is placed on a stable surface.

3. I2C Errors:

   • Ensure there are no conflicting devices on the I2C bus.

Conclusion

The MPU-6050 is a versatile motion sensor that can add precise motion tracking capabilities to your Raspberry Pi projects. By following this guide, you can set up and use the MPU-6050 for applications like robotics, stabilization systems, and IoT automation. Experiment with scaling and filtering data to fine-tune the sensor for your needs!