msinger
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Crash from a compass error and loss gps
- Thread starter DroneChris83
- Start date
I'm not quite sure what you are asking. I've never looked at an actual calibration process in a log, but I've personally seen the effects of calibrating in a magnetically distorted environment. And I've seen flight logs that showed anomalous magnetometer data causing problems that were subsequently fixed by calibration.
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msinger
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I'm asking you if you've ever seen a flight log that showed the flight was performed with a bad compass calibration. If you have a link to such a flight log, I'd love to check it out. I've never seen such a thing.
Ah - yes. I've seen a couple like that - I'll see if I can find them. One was the subject of analysis and discussion on here (or maybe MavicPilots) fairly recently.
You may be thinking of this @JJErrico 's incident
Request advice: Compass error, Yaw error, Weak GPS signal
The conclusion that I came to was that the problem was fixed by doing a compass calibration. BUT, it wasn't due to a flawed calibration because the P4 had not been calibrated for several flights and had not been exhibiting problems. The problems started abruptly and were fixed by a calibration. The other thing to note is that there was no indication from the Go App that a calibration was needed.
There have been other incidents like this. E.g. in this thread
Fly Away
Here it's less compelling that the compass calibration fixed the problem. BUT, it was not due to a flawed calibration as the P4 had many flights without a calibration and no problems.
The data are different - the first is unstable flight after a poor calibration (back in the P2 days so no logs unfortunately) while the second comprises logged anomalous magnetometer data that are clearly being affected by something onboard the aircraft. But the cause is the same - bad calibration data.
That may have been the one. But to clarify, I don't mean that the previous calibration was necessarily flawed when done - I simply mean that the magnetometers are out of calibration, i.e the "calibration" is the calibration dataset, not the calibration process. That could be due to a calibration done in a distorted magnetic field, magnetization of aircraft components by exposure to strong magnetic fields, or a change in or addition of components.
IMHO, bad calibration data due to a flawed calibration is extremely rare. I guess a significant part of this opinion comes from the fact that I've not see a situation where this has happened - always a suspect argument
. But, also if the geomagnetic environment is distorted enough to where bad calibration data result then I think the calibration will be rejected and a "interference detected, move to another location" error will be issued.
I agree that it's rare, and probably even rarer today than it was on the older aircraft, which were perhaps less able to detect a flawed calibration. But in the past I've both seen it happen and heard similar accounts from others. I've not seen it with the P3 or later, but then I've never recalibrated any of my newer aircraft.
The compass does not 'go out of calibration' .....
What happens is : If you calibrate in a bad area with local anomalies such as a boat dock for example. The compass accepts the calibration unless it falls outside of the programmed limits. You take off and as you fly away from the anomaly - the compass then says ERROR ...
Yes I have seen it ... there are many reports online of it .. and of the loss of the drone ion some cases ... if the resulting error is bad enough - it can also cause a 'fly-away' ... again more than a few posts on that one happening.
Nigel
No - the compass can go out of calibration - most commonly because either existing ferromagnetic components on the aircraft change their magnetization due to exposure to a strong magnetic field, or because components on the aircraft are added or changed. Either of those changes the field due to the aircraft itself and renders its previously stored corrections incorrect.
The P4pro+ now has in settings to rotate the actual remote controller one way then vertical just like the Drone to calibrate its compass. ???
I hope so since you need the device to be calibrated for the direction indicators in the apo to work properly its sort of dumb af that a setting wasnt there for that all along
What is the bottom line simple feedback with no added complicated tech speak. I have read here after mods have seen logs that they tell people they had a bad calibration because metal in the area. Now they say they have never seen this in logs. Wtf how bout a straight answer on this one. Ffs!
You have heard different opinions from different people. That's life. I suggest a hybrid approach, suggested earlier by @Meta4 - calibrate if you find problems and determine that they are not due to flying in a bad location, if the app tells you to calibrate, or if you change or magnetize/demagnetize any components on the aircraft.
On the specific point that you asked here, there are a couple of differing views. One is that a bad calibration (in a distorted environment) will not succeed (FC will report calibration failure) and so is not a problem. The other view (and I've seen this one but not since the P2 days) is that there is a situation in which a bad calibration is not actually bad enough to fail the FC criteria, but will negatively impact flight characteristics.
Those are both different situations from the one where a compass goes out of calibration due to something changing on the aircraft (that certainly can happen) or when an aircraft with a good calibration flies in a distorted magnetic field environment, which is clearly the most common problem.
Meta4
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That is so that the compass built into the tablet can be calibrated so that it knows which way it is facing.
This is unrelated to the compass in the Phantom - the one that's used for flight.
If you use another drone with a phone or tablet, you can calibrate those independently.
I wanted to close the loop on my experience. After talking with the support, they determined that it was covered under warranty and repaired the drone and sent it back at no cost to me.
If I ever figure out how to upload the data, I will.
This is what they repaired:
Phantom 3 Roll-axis Cover 1 2.00 2.00
Phantom 3 Yaw-axis Heat Dissipation Cover plate 1 4.00 4.00
Phantom 3 Roll-axis Bracket 1 6.00 6.00
Upper Cover 1 3.00 3.00
Phantom 3 Main Controller Board Module (2312) 1 96.00 96.00
Phantom 3 Roll Motor 1 8.00 8.00
Phantom 3 Advanced Gimbal Video Downlink Main Board V10 1 128.00 128.00
Phantom 3 Gimbal Roll-axis ESC Board 1 8.00 8.00
Phantom 3 Lower Cover Module 1 8.00 8.00
If I ever figure out how to upload the data, I will.
This is what they repaired:
Phantom 3 Roll-axis Cover 1 2.00 2.00
Phantom 3 Yaw-axis Heat Dissipation Cover plate 1 4.00 4.00
Phantom 3 Roll-axis Bracket 1 6.00 6.00
Upper Cover 1 3.00 3.00
Phantom 3 Main Controller Board Module (2312) 1 96.00 96.00
Phantom 3 Roll Motor 1 8.00 8.00
Phantom 3 Advanced Gimbal Video Downlink Main Board V10 1 128.00 128.00
Phantom 3 Gimbal Roll-axis ESC Board 1 8.00 8.00
Phantom 3 Lower Cover Module 1 8.00 8.00
Why do people calibrate the compass on their quad if they aren't having problems. It was stated in the initial post that he calibrates his compass at the beginning of each day. This is unnecessary and could possible lead to problems down the road. I have over 200 flights and have only re-calibrated the compass on my quad one time.
