Reasons for non stable hovering [gpsmode]
- Thread starter t2adze
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msinger
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Try calibrating the IMU again. It's important to make sure the Phantom is on a completely level surface when calibrating it.
Meta4
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A little wind shouldn't make much difference
You'll have to describe what you are seeing.
Non-stable could mean anything.
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If GPS signals are weak due to a canopy of trees. I can't fly gps mode down our road consistently because of this. Also, once I calibrated my compass while standing between to big steel picnic tables and had some trouble until I realized what I'd done and recalibrated.
A CME or Coronal Mass Ejection which is a solar flare will cause havoc on satellites thus causing erratic signals to the GPS system. There are several free apps that monitor these events that are reported as "K" index. The higher the K, the stronger the interference. K's of 5 or greater will mess the GPS system for hours.
Compass:
Check your compass mods while hovering about 12-15ft.
They should be around 1500. If they are +/- 200 while hovering then you may have influence (buildings/metal structures) or maybe a bad compass dance.
IMU:
Have you done a COLD IMU on a perfectly levelled surface?
VPS:
The VPS works by "remembering" what pattern it sees at heights less than 10ft. If the image keeps changing then it may be hard for it to "remember". Eg, on a windy grassy field or on water. Its best to turn off outdoors unless you rely on it.
Generally:
If you are at low altitudes, there is less sat counts as they are being blocked by mountains/trees/buildings. The P3A/P acceptable sat count is 8. Prop wash also causes stability at low altitudes.
Check your compass mods while hovering about 12-15ft.
They should be around 1500. If they are +/- 200 while hovering then you may have influence (buildings/metal structures) or maybe a bad compass dance.
IMU:
Have you done a COLD IMU on a perfectly levelled surface?
VPS:
The VPS works by "remembering" what pattern it sees at heights less than 10ft. If the image keeps changing then it may be hard for it to "remember". Eg, on a windy grassy field or on water. Its best to turn off outdoors unless you rely on it.
Generally:
If you are at low altitudes, there is less sat counts as they are being blocked by mountains/trees/buildings. The P3A/P acceptable sat count is 8. Prop wash also causes stability at low altitudes.
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IMU cali was done cold and on perfect surface.
Vps is off.
Gps signal is ok, its an open field in the middle of the city though.
Ill check compass tomorrow when hovering.
Its not very catastrophic but it kinda movesaway when hovering on 2 meter height. It was a little windy also.
Vps is off.
Gps signal is ok, its an open field in the middle of the city though.
Ill check compass tomorrow when hovering.
Its not very catastrophic but it kinda movesaway when hovering on 2 meter height. It was a little windy also.
No it will not. Solar activity has neglible impact on the P3. Or any other GPS system. This has been discussed at length.
OP, try with a regular imu cal, not a cold one. And by "perfect surface" you mean leveled with a spirit level? Both front to back, side to side, and across?
Also, a video of the errant behavior might help others diagnose.
