Motion Sensing

Accelerometers: detect linear acceleration of devices i.e. acceleration along the x,y, &/or z-axis
Gyroscopes: detect angular velocity i.e. speed at which device is turning along the x, y, &/or z-axis
both accelerometers and gyroscopes usually found inside an Inertial Measurement Unit (IMU)
Magnetometer: relies on the earth's magnetic field to determine the hosts object's orientation relative to the Earth's Magnetic North
- When combined with accelerometers and gyroscopes, can stabilize orientation calculations and determine orientation with respect to earth
***Accelerometers can detect the force of gravity by detecting the orientation due to gravity along it's axis i.e. can measure pitch and roll, but CANNOT determine yaw angle
*** Gyroscopes can measure roll, pitch and yaw by integrating the velocity values
- however, gyroscopes are prone to drift, which is why data is fused with accelerometers
- since accelerometers can't measure yaw, this value will drift unless
  - 1) Use gyroscope that has "self-correction" feature
  - 2) Fuse with accelerometer

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