以前在iphone中要得到加速度时，只能使用Accelerometer模块得到重力加速度分量，然后通过滤波得到加速度值。其实在ios中有一个陀螺仪模块，CoreMotion，使用更方便。
//初始化CoreMotion
#import
CMMotionManager *motionManager = [[CMMotionManager alloc]init];
//1. Accelerometer 获取手机加速度数据
CMAccelerometerData *newestAccel = motionManager.accelerometerData;
double accelerationX
= newestAccel.acceleration.x;
double accelerationY = newestAccel.acceleration.y;
double accelerationZ = newestAccel.acceleration.z;
//2. Gravity 获取手机的重力值在各个方向上的分量，根据这个就可以获得手机的空间位置，倾斜角度等
double gravityX
= motionManager.deviceMotion.gravity.x;
double gravityY
= motionManager.deviceMotion.gravity.y;
double gravityZ
= motionManager.deviceMotion.gravity.z;
//获取手机的倾斜角度：
double zTheta
= atan2(gravityZ,sqrtf(gravityX*gravityX+gravityY*gravityY))/M_PI*180.0;
double xyTheta
= atan2(gravityX,gravityY)/M_PI*180.0;
//zTheta是手机与水平面的夹角， xyTheta是手机绕自身旋转的角度
//3. DeviceMotion 获取陀螺仪的数据 包括角速度，空间位置等
//旋转角速度：
CMRotationRate rotationRate
= motionManager.deviceMotion.rotationRate;
double rotationX = rotationRate.x;
double rotationY = rotationRate.y;
double rotationZ = rotationRate.z;
//空间位置的欧拉角（通过欧拉角可以算得手机两个时刻之间的夹角，比用角速度计算精确地多）
double roll
= motionManager.deviceMotion.attitude.roll;
double pitch =
motionManager.deviceMotion.attitude.pitch;
double yaw
= motionManager.deviceMotion.attitude.yaw;
//空间位置的四元数（与欧拉角类似，但解决了万向结死锁问题）
double w
= motionManager.deviceMotion.attitude.quaternion.w;
double wx
= motionManager.deviceMotion.attitude.quaternion.x;
double wy
= motionManager.deviceMotion.attitude.quaternion.y;
double wz =
motionManager.deviceMotion.attitude.quaternion.z;
//通过陀螺仪模块可以实现模拟赛车，模拟射击等。