imu — IMU helper for the Arduino Nano 33 BLE Sense

Note

This page documents the Arduino Nano 33 BLE Sense’s Python imu module (a small wrapper around the on-board IMU drivers). For the OpenMV C-level imu module that ships on the OPENMV_N6, OPENMV_RT1060, and OPENMV_AE3 camera boards, see imu — imu sensor.

This module is a thin board-specific wrapper that exposes the on-board inertial measurement unit of the Arduino Nano 33 BLE Sense as a single IMU object. Both hardware revisions of the board are handled transparently:

• Rev 1 uses a single LSM9DS1 9-axis IMU.

• Rev 2 combines a Bosch BMI270 (accelerometer + gyroscope) with a Bosch BMM150 magnetometer.

The constructor probes the I2C bus for the BMI270 address (0x68) and selects the matching driver automatically, so user code can be written once and run on either revision.

Example:

import time
import imu
from machine import Pin, I2C

bus = I2C(1, scl=Pin(15), sda=Pin(14))
sensor = imu.IMU(bus)

while True:
    print('Accelerometer: x:{:>8.3f} y:{:>8.3f} z:{:>8.3f}'.format(*sensor.accel()))
    print('Gyroscope:     x:{:>8.3f} y:{:>8.3f} z:{:>8.3f}'.format(*sensor.gyro()))
    print('Magnetometer:  x:{:>8.3f} y:{:>8.3f} z:{:>8.3f}'.format(*sensor.magnet()))
    print("")
    time.sleep_ms(100)

class IMU

class imu.IMU(bus: 'machine.I2C')

Construct an IMU object bound to an I2C bus.

• bus is an initialised machine.I2C instance connected to the on-board IMU(s).

On construction the bus is scanned: if a device responds at address 0x68 a BMI270 plus BMM150 pair is instantiated (Nano 33 BLE Sense Rev 2), otherwise an LSM9DS1 is instantiated (Rev 1). The underlying driver is kept on the imu attribute and configured with default ranges and output data rates.

accel() → tuple[float, float, float]

Return the latest accelerometer reading as an (x, y, z) tuple in units of g (standard gravities).

gyro() → tuple[float, float, float]

Return the latest gyroscope reading as an (x, y, z) tuple in degrees per second.

magnet() → tuple[float, float, float]

Return the latest magnetometer reading as an (x, y, z) tuple in micro-tesla (uT).