Vectornav VN-100, Руководство пользователя

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82 UM001
6.2.2 Acceleration Compensation
Accelerometer Compensation
Register ID : 25 Access : Read / Write
Comment :
Allows the accelerometer to be further compensated for scale factor, misalignment, and
bias errors.
Size (Bytes): 48
Example Command: $VNRRG,25,1,0,0,0,1,0,0,0,1,0,0,0*75
Offset Name Format Unit Description
0 C[0,0] float -
4 C[0,1] float -
8 C[0,2] float -
12 C[1,0] float -
16 C[1,1] float -
20 C[1,2] float -
24 C[2,0] float -
28 C[2,1] float -
32 C[2,2] float -
36 B[0] float m/s
2
40 B[1] float m/s
2
44 B[2] float m/s
2
This register contains twelve values representing the accelerometer compensation parameters. The
accelerometer measurements are compensated for changes in bias, gain, and axis alignment that can
occur during the installation of the chip on the customer’s board using the following model. Under normal
circumstances this register can be left in its factory default state. In the event that there are significant
changes to the accelerometer bias, gain, and axis alignment during installation, then these registers allow
for further compensation. Note that this accelerometer compensation is separate from the compensation
that occurs during the calibration process at the factory. Setting this register to the default state of an
identity matrix and zero offset will not eliminate the accelerometer gain, bias, and axis alignment that
occur during factory calibration. These registers only need to be changed from their default values in the
event that changes in bias, gain, and axis alignment have occurred at some point between the times the
chip was calibrated at the factory and when it is used in the field.
{
𝑋
𝑌
𝑍 } = [
𝐶00 𝐶01 𝐶02
𝐶10 𝐶11 𝐶12
𝐶20 𝐶21 𝐶22 ] ∙ {
𝐴𝑋 − 𝐵0
𝐴𝑌 − 𝐵1
𝐴𝑍 − 𝐵2
}
The variables {AX,AY,AZ} are components of the measured acceleration. The {X, Y, Z} variables are the
new acceleration measurements outputted after compensation for changes during sensor mounting. All
twelve numbers are represented by single-precision floating points.