IMU – Inertial Measurement Unit

The IMU mounted on the SBC is the Bosch BMI088, a high-performance 6-axis inertial sensor (3 accelerometers + 3 gyroscopes) that allows for highly accurate measurement of orientation and detection of motion along three orthogonal axes.

Note

If you are an advanced IMU user and need to know more technical details, we suggest you take a look at the IMU manufacturer documentation.

Methods

class Imu

The Imu class allows you to easily configure the IMU settings and read its values.

read_acc_g()

Reads the IMU accelerometers values.

Return:

List with 3 elements of X,Y,Z axis accelerometer values in [G]

Example to read IMU accelerometer values:

>>> import sbc
>>> imu = sbc.Imu()
>>> print(imu.read_acc_g())
[0.009338379, -0.003387451, 0.9941711]

read_gyro_rad_s()

Reads the IMU gyroscopes values.

Return:

List with 3 elements of X,Y,Z axis gyroscope values in [rad/s]

Example to read IMU gyroscope values:

>>> import sbc
>>> imu = sbc.Imu()
>>> print(imu.read_gyro_rad_s())
[0.00186427, 0.007856565, 0.001731107]

read_temp_c()

Reads the IMU internal temperature sensor.

Return:

Internal temperature in [degC] units

Example to read IMU temperature:

>>> import sbc
>>> imu = sbc.Imu()
>>> print(imu.read_temp_c())
26.875

acc_config(freq_hz, range_g)

Configures IMU accelerometers frequency and range.
When the Imu class is instantiated, the accelerometer default values are 100Hz and 3G.

Args:

Parameter name	Value	Description
freq_hz	ACC_CONF_ODR_12_5 ACC_CONF_ODR_25 ACC_CONF_ODR_50 ACC_CONF_ODR_100 ACC_CONF_ODR_200 ACC_CONF_ODR_400 ACC_CONF_ODR_800 ACC_CONF_ODR_1600	Accelerometer output data rate values in Hz
range_g	ACC_RANGE_3_G ACC_RANGE_6_G ACC_RANGE_12_G ACC_RANGE_24_G	Accelerometer range in G

gyro_config(freq_hz, range_deg_s)

Configures IMU gyroscopes frequency and range.
When the Imu class is instantiated, the gyroscopes default values are 100Hz and 125deg/s.

Args:

Parameter name	Value	Description
freq_hz	GYRO_ODR_100 GYRO_ODR_200 GYRO_ODR_400 GYRO_ODR_1000 GYRO_ODR_2000	Gyroscope output data rate values in Hz
range_deg_s	GYRO_RANGE_125_DEG_S GYRO_RANGE_250_DEG_S GYRO_RANGE_500_DEG_S GYRO_RANGE_1000_DEG_S GYRO_RANGE_2000_DEG_S	Gyroscope range in deg/s