Polar H10 的加速度坐标系

参考：

Accelerometer raw data format question

Verity Sense inconsistent ACC Streaming

Acceleration data with gravity eliminated?

另外加速度的单位是 mG，参考下面

Accelerometer data with sample rates of 25Hz, 50Hz, 100Hz and 200Hz and range of 2G, 4G and 8G. Axis specific acceleration data in mG.