offset parameter units are milligauss
User settable parameters should have a User category defined. Those that should never be set by a user should not have this.
The function rotate_field() can change the values axes and the function
correct_field() applies offsets (which are already in milligauss). Thus any
sensitivity adjustment must be done for two reasons:
(1) The offsets must be applied to the values already in milligauss;
(2) The factory sensitivity adjustment values are per axis, if any rotation
that switches axes is applied, that'll mess with the adjustment.
Experiments showed that before this patch the length of the mag field reported
quite different from the expected. After this patch, the same experiments
showed reasonable values.
This is part of the transition to make all mag field values be used in
milligauss. Additionally the value of _gain_multiple is adapted to the new way
we're using it and corrected accordingly to the datasheets.
The use of _gain_multiple is not necessary because the values of
expected_{x,yz} and _mag_{x,y,z} are both in sensor raw unit (i.e., lsbs).
That wasn't fixed before in order not to make APM users to recalibrate their
compasses.
the previous approach assumed a 1:1 mapping between compass backends
and compass instances, which isn't true on PX4.
It also only setup milligauss offsets on a set_and_save call, which is
not the only way offsets change
this adds a milligauss_ratio per instance, which is considerably
simpler
AK8963 is configured in 16-bit ADC mode which implies sensitivity of 0.15 uT/LSb. Knowing this fact we can convert the measurements to the proper units. The change will make users recalibrate their compasses.
From now on there's a pair get_field_milligauss() and
get_offsets_milligauss() that can make the transition to the common
units across all compasses easier.
This commit changes the way libraries headers are included in source files:
- If the header is in the same directory the source belongs to, so the
notation '#include ""' is used with the path relative to the directory
containing the source.
- If the header is outside the directory containing the source, then we use
the notation '#include <>' with the path relative to libraries folder.
Some of the advantages of such approach:
- Only one search path for libraries headers.
- OSs like Windows may have a better lookup time.
