i have been flying my P4P for 2 days now. I owned a P3P for about 2 and a half years. I don’t see the option to calibrate compass before flight on the P4P DJI Go 4.0 app. I’m not sure if it’s the new app preventing me or the P4P. Before on the P3P you just clicked calibration where the compass option was. Am I missing something or did they take the feature off, if they did why?
Phantom 4 Pro - Compass Calibration issue
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msinger
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DJI recently removed it from the Aircraft Status screen. I'm assuming they did it since many people thought it was prompting them to calibrate the compass (rather than offering it as an option). They did not mention the change in their release notes.
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There is no need to recalibrate your compass before a flight (and there never was).
See p.57 of the P4 pro manual to see when DJI recommend calibrating the compass nowdays.
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@Meta4, you might find this article interesting (posted 9 days ago). In this article, DJI Support is recommending the compass be calibrated before every flight to ensure a safe flight.
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That kinda looks like the Sales folks utilizing dated information, IMHO. Maybe the internal communication at DJI is equal to the external...?
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No idea. Other than it being nothing more than a waste of time in most cases, calibrating the compass often doesn't seem to cause any problems.
It seems a lot of the toy drones now require a compass calibration to fly, every session. I just worry about the guy that does his calibration on concrete with rebar just below it. That's worse than NO compass.
Directly from DJI engineers is to NOT calibrate compass unless you are prompted to (since mavic and newer). This includes after moving to multiple areas and still receiving the compass error. I will try to contact someone to get that removed or edited.
The reason for this is because there's more chances of someone messing up a good calibration over one that has external influences added to the calibration.
The reason for this is because there's more chances of someone messing up a good calibration over one that has external influences added to the calibration.
I posted this over on the FB groups yesterday to try to explain this to the mavic and spark guys.. While the P4/P/A are not as sensitive the same rules apply.
I’ve noticed MANY post lately across the Mavic and Spark groups about fly a ways. Most if not all are user induced by calibrating in the influence of heavy metal, even small amounts.
These two craft are ultra sensitive since they set so low to the ground. They are also very sensitive since there’s already a lot of electronic noise stuffed in such a small footprint.
So what can you do to minimize GPS degradation (dropping down to ATTI)?
First things first, start with a valid compass calibration. This should be done in an open area without power lines, electronics or metals. Things as simple as jewelry, watches or belt buckles can play into the calibration on these craft.
Once you have a valid calibration there’s NO NEED to redo this before each flight (this is an old recommendation from older craft). The reason for this change is it only increases the odds of a user completing a bad calibration and overwriting a good one. Unless you have gone hundreds if not thousands of miles away from last calibration or stored the craft by a huge speaker, there’s absolutely no reason for a new compass calibration.
Now what happens if you see the Compass error in the app? Do as it states and move the aircraft to a new location. This is very important, if you just move a few feet and then calibrate craft, guess what happens? That’s right!! You will just calibrate that influence into the compass and once the craft moves far enough away from the magnetic field, the crafts compass bias versus imu will be too great and the craft will degrade GPS down to ATTI. Therefore, this is why you see loss of GPS with up to 18 birds in view.
The picture I attached shows both the error and what’s causing the error on the spark. This is a wood table, what's causing the error are the two leg bolts underneath 4 inches of wood. Hopefully this shows how sensitive these things can be.
I will add one more thing, you can have small influences come into play. These type of issues show up in things like toilet bowl ( craft circling while in a hover), curved routes while only directing the craft to go forward or J hooks while coming to a stop. Unfortunately there’s not much else to suggest but to try another calibration in an open area or the environment could just have too much magnetic or electronic interferences. You would then need to select and different location or fly with the encountered offsets.
If you have any questions comments or concerns please post below!
I’ve noticed MANY post lately across the Mavic and Spark groups about fly a ways. Most if not all are user induced by calibrating in the influence of heavy metal, even small amounts.
These two craft are ultra sensitive since they set so low to the ground. They are also very sensitive since there’s already a lot of electronic noise stuffed in such a small footprint.
So what can you do to minimize GPS degradation (dropping down to ATTI)?
First things first, start with a valid compass calibration. This should be done in an open area without power lines, electronics or metals. Things as simple as jewelry, watches or belt buckles can play into the calibration on these craft.
Once you have a valid calibration there’s NO NEED to redo this before each flight (this is an old recommendation from older craft). The reason for this change is it only increases the odds of a user completing a bad calibration and overwriting a good one. Unless you have gone hundreds if not thousands of miles away from last calibration or stored the craft by a huge speaker, there’s absolutely no reason for a new compass calibration.
Now what happens if you see the Compass error in the app? Do as it states and move the aircraft to a new location. This is very important, if you just move a few feet and then calibrate craft, guess what happens? That’s right!! You will just calibrate that influence into the compass and once the craft moves far enough away from the magnetic field, the crafts compass bias versus imu will be too great and the craft will degrade GPS down to ATTI. Therefore, this is why you see loss of GPS with up to 18 birds in view.
The picture I attached shows both the error and what’s causing the error on the spark. This is a wood table, what's causing the error are the two leg bolts underneath 4 inches of wood. Hopefully this shows how sensitive these things can be.
I will add one more thing, you can have small influences come into play. These type of issues show up in things like toilet bowl ( craft circling while in a hover), curved routes while only directing the craft to go forward or J hooks while coming to a stop. Unfortunately there’s not much else to suggest but to try another calibration in an open area or the environment could just have too much magnetic or electronic interferences. You would then need to select and different location or fly with the encountered offsets.
If you have any questions comments or concerns please post below!
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Can you reference just one instance where this happened and there is an attached flight log so we can review the data?
All of the logs we reviewed in this forum have only shown the pilot launched from a location that was near a magnetic metal object.
This just isn't correct. I've looked at literally dozens of fly aways and in every case they were caused by launching from a geomagnetically distorted site. They were not caused by a compass calibration. I've never seen an incident where there was compelling evidence that it was caused by a flawed compass calibration. If you know of one please provide a link.
The misconception that a flawed calibration occurs because of calibrating in a geomagnetically distorted location has been around a long time. But, it's mathematical impossible for a calibration to detect and then compensate for magnetic anomalies that don't rotate with the AC; i.e. that are external to the AC.
I suppose it's possible that a watch could yield a flawed calibration, but only if the AC did not change hands or otherwise move in relation to the watch. I.e., the watch would rotate with the AC. In essence the watch is part of the AC during the calibration but then removed for flight resulting in a flawed calibration.
If magnetic anomalies external to the AC are significant enough the calibration can not be completed and will be rejected. In this case the standard "magnetic interference move to another location" error message will be issued.
This reminds me of this incident
My Spark crashed! Can you help determine why?
It was caused by a screw in the wood rail where the Spark was launched. But, here again, this wasn't caused by a flawed compass calibration, it was caused by launching from a geomagnetically distorted site.
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