CMMotionManager¶

Streams accelerometer, gyroscope, magnetometer, and fused device-motion data from the device.

Description¶

Wraps Apple’s CMMotionManager. Configure an update interval, call one of the start_*_updates methods, and connect to the matching signal to receive samples.

Prefer device_motion_updated over raw accelerometer_updated / gyro_updated / magnetometer_updated when you need gravity-separated user acceleration, bias-corrected rotation, or device attitude.

Platform availability: Real implementation on iOS. On other platforms the manager exists but is_*_available returns false and calling start_*_updates emits update_failed.

See Apple’s CMMotionManager reference.

Tutorials¶

CoreMotion Integration Guide

Methods¶

void	start_accelerometer_updates()
void	start_device_motion_updates(referenceFrame: AttitudeReferenceFrame)
void	start_gyro_updates()
void	start_magnetometer_updates()
void	stop_accelerometer_updates()
void	stop_device_motion_updates()
void	stop_gyro_updates()
void	stop_magnetometer_updates()

Signals¶

accelerometer_updated(accelerometer: CMAccelerometerData) 🔗

Emitted on the main thread when a new accelerometer sample is available.

device_motion_updated(deviceMotion: CMDeviceMotion) 🔗

Emitted on the main thread when a new fused device-motion sample is available.

gyro_updated(gyro: CMGyroData) 🔗

Emitted on the main thread when a new gyroscope sample is available.

magnetometer_updated(magnetometer: CMMagnetometerData) 🔗

Emitted on the main thread when a new magnetometer sample is available.

update_failed(message: String) 🔗

Emitted when CoreMotion reports an error or when the API is unavailable on the current platform.

Enumerations¶

enum AttitudeReferenceFrame: 🔗

AttitudeReferenceFrame XARBITRARY_Z_VERTICAL = 1

Z axis vertical, X axis aligned with an arbitrary direction in the horizontal plane.

AttitudeReferenceFrame XARBITRARY_CORRECTED_Z_VERTICAL = 2

Same as XARBITRARY_Z_VERTICAL but corrected for magnetometer drift.

AttitudeReferenceFrame XMAGNETIC_NORTH_Z_VERTICAL = 4

Z axis vertical, X axis pointing toward magnetic north. Requires the magnetometer.

AttitudeReferenceFrame XTRUE_NORTH_Z_VERTICAL = 8

Z axis vertical, X axis pointing toward true north. Requires the magnetometer and Location Services.

Property Descriptions¶

CMAccelerometerData accelerometer_data 🔗

CMAccelerometerData get_accelerometer_data()

The most recent accelerometer sample, or null if none is available.

float accelerometer_update_interval 🔗

void set_accelerometer_update_interval(value: float)
float get_accelerometer_update_interval()

Desired interval between accelerometer samples in seconds.

CMDeviceMotion device_motion 🔗

CMDeviceMotion get_device_motion()

The most recent device-motion sample, or null if none is available.

float device_motion_update_interval 🔗

void set_device_motion_update_interval(value: float)
float get_device_motion_update_interval()

Desired interval between device-motion samples in seconds.

CMGyroData gyro_data 🔗

CMGyroData get_gyro_data()

The most recent gyroscope sample, or null if none is available.

float gyro_update_interval 🔗

void set_gyro_update_interval(value: float)
float get_gyro_update_interval()

Desired interval between gyroscope samples in seconds.

bool is_accelerometer_active 🔗

bool get_is_accelerometer_active()

true when accelerometer updates are currently being delivered.

bool is_accelerometer_available 🔗

bool get_is_accelerometer_available()

true when the device has an accelerometer available to this binding.

bool is_device_motion_active 🔗

bool get_is_device_motion_active()

true when device-motion updates are currently being delivered.

bool is_device_motion_available 🔗

bool get_is_device_motion_available()

true when fused device-motion is available on this device.

bool is_gyro_active 🔗

bool get_is_gyro_active()

true when gyroscope updates are currently being delivered.

bool is_gyro_available 🔗

bool get_is_gyro_available()

true when the device has a gyroscope available to this binding.

bool is_magnetometer_active 🔗

bool get_is_magnetometer_active()

true when magnetometer updates are currently being delivered.

bool is_magnetometer_available 🔗

bool get_is_magnetometer_available()

true when the device has a magnetometer available to this binding.

CMMagnetometerData magnetometer_data 🔗

CMMagnetometerData get_magnetometer_data()

The most recent magnetometer sample, or null if none is available.

float magnetometer_update_interval 🔗

void set_magnetometer_update_interval(value: float)
float get_magnetometer_update_interval()

Desired interval between magnetometer samples in seconds.

Method Descriptions¶

void start_accelerometer_updates() 🔗

Begins delivering accelerometer samples via accelerometer_updated. Sampling cadence is controlled by accelerometer_update_interval.

void start_device_motion_updates(referenceFrame: AttitudeReferenceFrame) 🔗

Begins delivering fused CMDeviceMotion samples via device_motion_updated. referenceFrame selects how attitude is referenced. Pass XMAGNETIC_NORTH_Z_VERTICAL or XTRUE_NORTH_Z_VERTICAL to align yaw with magnetic or true north (requires the magnetometer).

void start_gyro_updates() 🔗

Begins delivering gyroscope samples via gyro_updated. Sampling cadence is controlled by gyro_update_interval.

void start_magnetometer_updates() 🔗

Begins delivering magnetometer samples via magnetometer_updated. Sampling cadence is controlled by magnetometer_update_interval.

void stop_accelerometer_updates() 🔗

Stops accelerometer updates.

void stop_device_motion_updates() 🔗

Stops device-motion updates.

void stop_gyro_updates() 🔗

Stops gyroscope updates.

void stop_magnetometer_updates() 🔗

Stops magnetometer updates.

CMAccelerometerData	accelerometer_data
float	accelerometer_update_interval
CMDeviceMotion	device_motion
float	device_motion_update_interval
CMGyroData	gyro_data
float	gyro_update_interval
bool	is_accelerometer_active
bool	is_accelerometer_available
bool	is_device_motion_active
bool	is_device_motion_available
bool	is_gyro_active
bool	is_gyro_available
bool	is_magnetometer_active
bool	is_magnetometer_available
CMMagnetometerData	magnetometer_data
float	magnetometer_update_interval