AN4156

Sensor HAL: files

Doc ID 023584 Rev 1

7/12

Figure 2.

ENU coordinate system

Figure 3 shows the accelerometer, magnetometer and gyroscope placed on a PCB. The

orientation of the device on the PCB can be done in the driver code through the

axis_map_x

, axis_map_y and axis_map_z variables or with rotation matrices.

Figure 3.

Example of sensor placement on the board

The transformation matrices are defined as:

The single coordinate system for each sensor is visible in the sensor datasheet.

xb yb zb

xs ys zs

x1 x2 x3

y1 y2 y3

z1 z2 z3

⋅

xs

x1 xs

y1 zs

z1

⋅

+

⋅

+

⋅

xs

x2 xs

y2 zs

z2

⋅

+

⋅

+

⋅

xs

x3 xs

y3 zs

z3

⋅

+

⋅

+

⋅

T

==