DroneCAN Magnetometer Array¶
ArduPilot can be used to create a multiple magnetomer array using DroneCAN compasses. This could be useful as a suspended device for geophysical surveys or other uses.
An ArduPilot autopilot (used only for the array logging, not for vehicle control) could support many DroneCAN compasses as shown below:
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And could be suspended below a vehicle as shown below:
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image courtesy of AerialVision
Each compass would have its raw x/y/z field readings logged by the MAGH message.
This capability is not included by default and would have to be included in a custom build for the autopilot using the Custom Firmware Build Server and enabling the “DroneCAN HiRes compasses for survey logging” option under Compass.
The autopilot would need to have LOG_DISARMED parameter set to log as soon as power is supplied.