Yesterday we experienced a large drone gradually dropping height for a mission to test flight for an hour. When it drops height, the pilot throttles up a few meters (1-2m), and after some time, it drops height again. This was repeated and Mission Planner (MP) showed 10.x m in height at the end of the one hour flight, but physically the drone was just 2.x m above the ground all along.
Any experts can guide and narrow down what is the likely cause.
FW: Arducopter 4.1.5
Air pressure changes over time, changing the barometer readings.
I am still beginner in reviewing the flight log, From the flight log, any section I can guide our customer to view and prove this point?
Besides that, will mounting a rangefinder to get the height helps in this situation?
Take a look at the
BARO messages in the flight log.
Yes, a rangefinder helps, if it is precise and accurate.
I guess we don’t use GPS values to correct barometer readings over time? Seems like a (heavily filtered) GPS altitude might be useful to correct barometer drift.
Maybe a barometer on the ground(lots of cell phones have them) could be used to track baro pressure changes over time to prove this is where the effect is coming from?