Any ideas? Yesterday my altitude readings started at -350 when sitting on the ground. The higher I went the numbers worked their way to Zero eventually.
Any ideas on what causes this?
Thanks
Any ideas on what causes this?
Thanks
??? My Altitude Readings start at -350 on ground ???
- Thread starter flyingtim
- Start date
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That is way off. You should do an advanced IMU calibration while the bird is cold.
Generally, the altitude values go up as they warm up. You should always cycle the bird after your field calibration and make sure your home lock readings are close to actual to prevent a possible flyaway (loss of satelights going to a different home).
That is way off. You should do an advanced IMU calibration while the bird is cold.
Generally, the altitude values go up as they warm up. You should always cycle the bird after your field calibration and make sure your home lock readings are close to actual to prevent a possible flyaway (loss of satelights going to a different home).
The compass has nothing to do with altitude; it is for heading only.
The bird gets altitude readings from GPS and the NAZA altimeter.
The thing to remember is that GPS, while great for position, is seriously weak in the altitude category.
An altimeter is more accurate, but you must know the barometric pressure at the particular time and location,
and it must be compensated for in the altitude calc, which cannot be done in the existing hardware.
Aircraft pilots are constantly advised of the local "altimeter" settings by A.T.C. for that very reason. ("two niner, niner two", etc.)
If you have a large storm approaching, and the B.P. drops, you will get a different altitude reading sitting in the same spot.
The bird uses the altimeter in a relative way to hover; it just tries to keep the reading steady.
It is not accurate for an absolute altitude reading.
The bird gets altitude readings from GPS and the NAZA altimeter.
The thing to remember is that GPS, while great for position, is seriously weak in the altitude category.
An altimeter is more accurate, but you must know the barometric pressure at the particular time and location,
and it must be compensated for in the altitude calc, which cannot be done in the existing hardware.
Aircraft pilots are constantly advised of the local "altimeter" settings by A.T.C. for that very reason. ("two niner, niner two", etc.)
If you have a large storm approaching, and the B.P. drops, you will get a different altitude reading sitting in the same spot.
The bird uses the altimeter in a relative way to hover; it just tries to keep the reading steady.
It is not accurate for an absolute altitude reading.
Meta4
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Because the Phantom doesn't attempt to give an altitude above sea level but only gives altitude relative to home point, and because a typical flight is 20 mins or less, correcting the barometer isn't necessary. It's accurate enough for our purposes.
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