Contents

CMDeviceMotion

Encapsulated measurements of the attitude, rotation rate, and acceleration of a device.

Declaration

class CMDeviceMotion

Overview

An application receives or samples CMDeviceMotion objects at regular intervals after calling the startDeviceMotionUpdates(using:to:withHandler:) method, the startDeviceMotionUpdates(to:withHandler:) method, the startDeviceMotionUpdates(using:) method, or the startDeviceMotionUpdates() method of the CMMotionManager class.

The accelerometer measures the sum of two acceleration vectors: gravity and user acceleration. User acceleration is the acceleration that the user imparts to the device. Because Core Motion is able to track a device’s attitude using both the gyroscope and the accelerometer, it can differentiate between gravity and user acceleration. A CMDeviceMotion object provides both measurements in the gravity and userAcceleration properties.

Topics

Getting Attitude and Rotation Rate

Getting Acceleration Data

Getting the Calibrated Magnetic Field

Getting the Heading

Getting the Sensor Location

See Also

Device motion