Inverted Hx components for some of the LSM303 devices
We noticed that some compasses have an twist evolving opposed compared to the others, due to inverted axes in the compass chips. There are 2 sub-types of LSM chips, (namely 'D' and 'AGR') defined differently
In addition, some differences were found in the layout of the AHRS device with respect to the LSM303D device. This was documented in 2016
- AHRS compass device: https://docs.google.com/presentation/d/18VM8rgqarHcLuqfpnWZ1FwljRp5UAE6K/edit#slide=id.p1
- LSM303D compass device: https://docs.google.com/presentation/d/1R7FVoACu3Z6_bJh9Fd8M8NUR319quQyL/edit#slide=id.p1
The km3compass software should account for these differences, and implement an automatic change in the rotation matrix in order to correct for this axes definition. The change should be present both in the magnetic field and in the acceleration measurements.