Altimeter

Configuration: Altimeter | Nodes: cas xhawk ers nav

Static pressure sensor estimates altitude from pressure readings.

  • ps - this setting enables the driver
    • off - the static pressure sensor is powered off and there’s no data output
    • altimeter - the sensor provides altitude and vertical speed fixes for autopilot, the output is sent through variables altps and vario.
    • meteo - the sensor provides altitude for ground control, and the output is sent through variable altitude.
  • prio - redundancy priority for sensor.
    • primary - data will be used when available.
    • secondary - data will be used when primary is unavailable.
    • low - level3 priority, used when primary and secondary is unavailable.
    • safety - used when no other sources are available.
  • AT - the sensor will update the variable AT (ambient temperature) with the temperature of the sensor itself. This is used on small UAVs where the outside temperature sensor is not available.
  • tbaro - the altitude estimator will use the ambient temperature from the variable AT to compensate the air density. Note, this setting should be turned off if you don’t have the outside air temperature sensor.
  • kalman - filter settings for altitude estimations (Q=0.5, R=20 for AP10)
  • kvfs - filter settings for vertical speed estimations (normally is off =0)

To estimate real noise of the sensor, you may need to temporally setup AHRS as follows:

  • AHRS/hGPS = baro
  • AHRS/fbar = none

The raw pressure readings will be shown in altitude and vspeed variables.

On normal operation, the output of the sensor is filtered through AHRS subsystem to provide high precision estimates.