"Reading notes" ios-accelerometer with gyroscope

One, the "filter" of the data

The raw data obtained directly from the accelerometer is often not used directly, but some disturbing data needs to be removed, a process called "filtering". The word "filter" is derived from the process of radio signal processing in radio technology. In fact they are the same from the mathematical point of view, they are some kind of sampling signal, this "filtering" process is very complex, to achieve "filter" by Fourier transform.

Two, gyroscope

Accelerometers can only measure the linear acceleration on the device, the tilt, deflection, and rotation of the accelerometer cannot be measured, which requires the use of a gyroscope, also called a angular velocity sensor.

Reference: "Best Practices for iOS sensor application development"

"Reading notes" ios-accelerometer with gyroscope