P4 Advanced Authorization Zone Mid Flight & Compass Error

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I thought I'd post a situation that happened to me a few weeks ago in case someone else has had the same issue out there. I'm completely disappointed in the new firmware and how it has been programmed to handle Authorization Zone situations.

The first flight was great. Hours after purchasing it from a local Best Buy I flew it around for 15 minutes and tested the functions, adjusted some settings to my liking and prepped for a job I had the next day. I was supposed to inspect a rooftop on a warehouse for a solar company. I looked at my sectional charts and the warehouse was relatively close to an airport but not an issue for the job. According to the DJI maps I was close to an authorization zone but in a warning zone and I had flown this spot before with the P4 original without issue.

I went to the location and turned on the P4 advanced. Brand new, tested, ready to fly. I calibrated everything prior at the original flight and made sure the RTH location was set correctly on the map. I got the green ready to fly signal and lifted the drone. So as not to annoy the bystanders I initially lifted the drone to about 200ft while I planned my route. My spotter was about 300 feet away on the other corner of the building.

As soon as I lifted off and was sending the drone to the 200ft mark a message popped up. It took over most of my screen and seemed to lock me out. It said something about sending the drone to its "home location" while I authorized my flight. Again I never had this message with the P4 original and I was already aware that I was not in an authorization zone. Either way, the new firmware/software said I was and sent me this message. The drone, however, started heading NW, away from me. I became 100% distracted by the "authorization zone" processes as it seemed, at the time, to have completely locked me out until authorization was granted. I was trying to race the system as fast as I could, waiting for the text message with the auth code to arrive. I finally got a code and typed it in but by that time the aircraft had disconnected. Since it went over a nearby forest there was no way to chase it.

I sent the flight logs to DJI about 3 weeks ago and have not had any official response yet.

I uploaded the TXT flight log to the online tool and everything in the beginning of the flight checks out fine. On the way up to 200ft it started getting GPS position no match errors, and then Compass errors. Then it automatically switched to ATTI mode. I am not a pro at deciphering these logs so I won't try.

I attached my flight log if anyone wants to analyze.

My thoughts here are...

1) The system should not allow you to lift the UAV if it is later going to deny them the ability to fly once in the air.

2) The software should never lock someone out of controlling their drone for obvious safety reasons. The drone can warn a pilot that they are out of bounds but should not lock them. This is because the drone software may not have the correct information as to where it is, but a person always knows. And perhaps there was no lock in this situation, but the way the Auth Zone was presented made it seem as such. Maybe there's a better way to prompt on the screen during flight so that pilots like me that are new to the new firmware don't get as confused as to the order of operations.

3) Most importantly, if the software knows that there are GPS or Compass issues, do not send the drone to its home location, cancel that action immediately, even if the Geo fencing software thinks the drone is inside an authorization zone. My flight log shows it was flying away from me at about 14 mph. I lost full connection a little over a minute into the flight. It probably took me about a minute to deal with the pop-up authorization messages and wait for the text message. What if I was in an area with no cell service?

UPDATE :::: (After discussion with the forum, the UAV may have never accepted the RTH command that the screen said it was sending out due to the Auth Zone. If the UAV went into ATTI mode before the Auth Zone message then that would make sense that the RTH command was blocked which is desired behavior. The NW 14mph drift therefore would have been ATTI mode drift).
 

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Sorry for your PT! You will learn that DJI and their "Customer Service" is anything but that. They will lie to you when simply telling the truth would be easier. You can talk to ten different "reps" and none of them will know what the others told you or what you told them. It is first if all, pilot error, NEVER DJI's fault. I had a crash in January when my P4 suddenly flipped over and powered into the ground from 200 feet! They NEVER told me how or why that happened even I submitted proof that a normal P4 can't do that! I paid the itemized repair cost hoping to get my drone back but they sent me a new one to shut me up. They would not tell me why my drone was not repairable even though I flew it two days AFTER the crash! To this date, some six months later, DJI still won't tell me what went wrong!!!

Get used to DJI's lies. They are a way of life for them!

Good luck, don't give up! Keep after them and keep copies of everything! You'll need it.
Jim
WA5TEF
 
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This is why I will never going to buy the new expensive toys from DJI... Even the new Spark is having issues falling from the sky without any warnings. I have my P3 standard and no issues so far but once this bird is gone, I will probably buy a refurbished p3 advanced. I am not going to spend money in their new stuff because if you check this forum you will see so many issues going on with their firmware in P4, advanced and pro.
 

Meta4

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I see the problem with your flight shows up when you are only 25 feet above the home point and from then on you have constant yaw errors and compass errors.
The GPS Position NoMatch errors are a false alarm and mean nothing.
I calibrated everything and made sure the RTH location was set correctly on the map. I got the green ready to fly signal and lifted the drone.
What did you calibrate and why? The manual doesn't advise you to calibrate anything.
Where did you launch from? Was it a steel or reinforced concrete surface perhaps?
The kind of flight record you've got peppered with yaw errors and ending with the Phantom zooming away is usually caused by a bad compass calibration and/or launching close to a lot of steel.
This explains how that happens: Looking for Trouble ??
Never mind anything about authorisation areas etc - Never launch from steel or reinforced concrete because that's what's caused the problem.
 
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Attached is a screen shot of the flight on Google Earth. What are those things near to the take-off point - truck trailers? If so, there's a lot of steel in them, of course, not to mention also possibly, rebar in the ground construction below to take their weight. You appear to have taken off, I would guess, from between two of them. If you also calibrated in the same area, then therein lie the problems, IMHO.

Sympathies anyway - it's not a nice feeling.

Take-off.jpg
,
 
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That satellite photo is not what it looked like the day of. Those trucks we're not there. The UAV was launched from the grassy area just next to the concrete. I am aware of the issues caused by launching next to metallic objects but it is possible that there was steel or other metal either beneath the ground or a ton of it in the concrete nearby.

This still doesn't excuse the DJI software from automatically doing a RTH and forcing me to obtain a token before I could get control of my screen back. And why was I forced to authorize when I wasn't in an authorization zone, but just approaching close by to one?
 
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That satellite photo is not what it looked like the day of. Those trucks we're not there. The UAV was launched from the grassy area just next to the concrete. I am aware of the issues caused by launching next to metallic objects but it is possible that there was steel or other metal either beneath the ground or a ton of it in the concrete nearby.

This still doesn't excuse the DJI software from automatically doing a RTH and locking me out. And how does it explain the GPS errors? And why was I forced to authorize when I wasn't in an authorization zone?
Yes, I realise that trailers are moveable items and may well have not been there as shown on the old satellite picture. However, analysis at Airdata UAV shows, rightly or wrongly, that one of the obstacle avoidance sensors was activated at 0.3 secs and at 1 m off the ground. Do you have any recollection of what that might have been?

At no point in the .csv log file is it shown that the aircraft activated RTH. As far as I can make out, it took off, home point was correctly recorded and remained the same throughout the flight. At 4.8 seconds there is a brief GPS No Match Error at 5m altitude, followed immediately, as @Meta4 has stated, by a load of compass and yaw errors which lasted until the recorded end of the flight. At 8.3 seconds it exited P-GPS mode and went into ATTI mode. At 9.7 seconds you have an error "[IMU]heading exception (In Flight) please switch to atti mode if craft behave abnormally ".

I'm afraid that I'm probably with Meta4 on this one - possibly a bad compass calibration and taking off with metal nearby, most likely underfoot if there were absolutely no trailers around. I'm not doubting at all what you say you saw onscreen and it's all very puzzling - but at no time did the aircraft try to RTH nor are any of the events you describe listed in the .csv file.

I think the authorisation process that you describe, whether triggered rightly or wrongly, is a completely separate issue from the flyaway. As regards the flyaway, the aircraft had a GPS mismatch (although you still had plenty of satellites), lost compass, then got 'confused' and took off as if its tail was on fire....
 
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Yes, probably me!

Ahah... and yes that is my issue with the new software. Of course it doesn't show it. I know for a fact that "Authorization Zone" messages popped up and that a message said it was performing a RTH. I did not have the choice to cancel it to my knowledge. I could not get the Authorization Zone message to disappear it was blocking most of the screen until I could get a token. Maybe there was a backdoor somewhere to cancel the RTH but in the moment of trying to solve the Authorization Zone issue it appeared to me that I had to to obtain a code before doing anything else and that the aircraft was "taken care of" in the meantime.

The RTH message wasn't captured in the log but I saw it. Maybe the message came up but something prevented the RTH from actually happening. They simply didn't record the Auth Zone messages. I can prove the Authorization Message with the token's I received by text message.

The entire issue here is the massive mid flight distraction of the Authorization Zone messages mid flight. You can warn a pilot but a human mind is always needed in the process... the computer should only assist and advise.



Yes, I realise that trailers are moveable items and may well have not been there as shown on the old satellite picture. However, analysis at Airdata UAV shows, rightly or wrongly, that one of the obstacle avoidance sensors was activated at 0.3 secs and at 1 m off the ground. Do you have any recollection of what that might have been?

At no point in the .csv log file is it shown that the aircraft activated RTH. As far as I can make out, it took off, home point was correctly recorded and remained the same throughout the flight. At 4.8 seconds there is a brief GPS No Match Error at 5m altitude, followed immediately, as @Meta4 has stated, by a load of compass and yaw errors which lasted until the recorded end of the flight. At 8.3 seconds it exited P-GPS mode and went into ATTI mode. At 9.7 seconds you have an error "[IMU]heading exception (In Flight) please switch to atti mode if craft behave abnormally ".

I'm afraid that I'm probably with Meta4 on this one - possibly a bad compass calibration and taking off with metal nearby, most likely underfoot if there were absolutely no trailers around. I'm not doubting at all what you say you saw onscreen and it's all very puzzling - but at no time did the aircraft try to RTH nor are any of the events you describe listed in the .csv file.

I think the authorisation process that you describe, whether triggered rightly or wrongly, is a completely separate issue from the flyaway. As regards the flyaway, the aircraft had a GPS mismatch (although you still had plenty of satellites), lost compass, then got 'confused' and took off as if its tail was on fire....
 
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Meta4

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The entire issue here is the lock out caused by the Auth Zone and the automated RTH. Locking a pilot out of manual control, no matter the circumstance, is a no no. You can warn a pilot but a human mind is always needed in the process... the computer should only assist and advise.
Sorry but if you read the link I included in post #4 and any other case of a Phantom going uncontrollable with yaw errors after launching from reinforced concrete or close to a lot of steel, that is exactly what happens.
What you experienced was not related to any authorisation zone issue or messages on the screen.
You weren't locked out by anything DJI did or programmed.
 

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I read it in its entirety. You're missing the point. So I give up... you must work for DJI.
Sorry but I'm not missing the point.
Your "point" is based on an invalid assumption.
Had you been flying from a magnetically clean launch point, and a good compass calibration any number of authorisation messages could have popped up but the Phantom wouldn't have dashed off on its own.
Your flight record looks a lot like several I have investigated where the launch was on steel or reinforced concrete.

If you want a second opinion perhaps @BudWalker could look at your incident. He's very good at that sort of thing.

And just for your info, I don't work for DJI. No-one here does.
Phantompilots is completely independent of DJI and we all buy our own drones just like you do.
 
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Metallic or not, the RTH procedure should not have been automatically activated by their software if the software knew of a compass error.
 
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Meta4

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Metallic or not, the RTH procedure should not have been automatically activated by their software if the software knew of a compass error. That's it, plain and simple.
That's another invalid assumption.
There is no hint of any RTH initiating during the flight.
The compass system was screwed up and the whole recorded flight was in atti mode.
Once the compass system is screwed up like that, all bets are off.
 
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Assumption? This is no assumption. I was there, I saw it. I saw a message that stated clearly that a RTH procedure was being initiated until an authorization token was generated. It was not recorded in the log. This is my entire point. Things happened that I witnessed in the software that you did not witness and will never be able to see in the log file.
 

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Assumption? This is no assumption. I was there, I saw it. I saw a message that stated clearly that a RTH procedure was being initiated until an authorization token was generated. It was not recorded in the log. This is my entire point. Things happened that I witnessed in the software that you did not witness and will never be able to see in the log file.
But it didn't happen. If it did, the flight data would have showed that.
And where do you think this RTH was going to?
You started the Phantom and it recorded a home point, you flew a few feet and reset home to 40.8386503 -72.8942242.
And that is the home point that shows in every line of data for the rest of the flight.
But without a functioning compass system your Phantom can't RTH to anywhere anyway.
 
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Believe me or not, I'm trying to make a point here that the RTH data and Auth Zone data is not showing in the log file despite that being exactly what happened. You're saying that it is literally impossible for DJI to have messed up the programming and that is impossible for it to not show up in the log file. I'm proof that an RTH message was triggered automatically by DJI's software due to an authorization zone and it was not recorded. Maybe the drone didn't actually activate the RTH but the message said it was doing so.

I never reset home. The majority of the time I was dealing with Auth Zone messages and trying to get token's sent to my phone. I wish I had screenshotted it but was busy trying to save the drone. I have no clue where the updated home point is, I only know the direction the drone flew.


But it didn't happen. If it did, the flight data would have showed that.
And where do you think this RTH was going to?
You started the Phantom and it recorded a home point, you flew a few feet and reset home to 40.8386503 -72.8942242.
And that is the home point that shows in every line of data for the rest of the flight.
 
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Meta4

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Believe me or not, I'm trying to make a point here that the RTH data and Auth Zone data is not showing in the log file despite that being exactly what happened. You're saying that it is literally impossible for DJI to have messed up the programming and that is impossible for it to not show up in the log file. I'm proof that RTH was triggered automatically by DJI's software due to an authorization zone and it was not recorded. Take my word for it or don't. I don't care.

I never reset home. The majority of the time I was dealing with Auth Zone messages and trying to get token's sent to my phone. I wish I had screenshotted it but was busy trying to save the drone. I have no clue where the updated home point is, I only know the direction the drone flew.
Ok .. the Phantom stored an updated home point a couple of feet from your launch point, that's not uncommon
When you have screwed up your compass system as is evident from the flight data, crazy things can happen (as they did).
The Phantom's home point did not change at all from 2 seconds after launch and remained back where you were.
But it seems that you're not going to believe anything I say and have your own theories that the data is invalid so there's nothing else I can do for you.
Good luck with DJI
 
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If you want to see what I saw, update your firmware to the latest version and go fly on the border of a few auth zones. I had a bad cell signal at the time so if you want to replicate you may need to turn off cell data, get the UAV in flight, then turn on your cell data once its launched. When I get another drone I'll follow up this thread with screenshots if I can get back to an Auth Zone.
 
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Meta4

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If you want to see what I saw, update your firmware to the latest version and go fly on the border of a few auth zones. I had a bad cell signal at the time so if you want to replicate you may need to turn off cell data, get the UAV in flight, then turn on your cell data once its launched. When I get another drone I'll follow up this thread with screenshots if I can get back to an Auth Zone. I swear to God that their software initiated a RTH because of the Auth Zone.
Last time ... it doesn't matter what was on your screen, it didn't have anything to do with what the Phantom actually did which is recorded in the flight data.
The messages on your screen are a distraction from what happened and what caused it.
The screen messages and your attempts to deal with them never got a chance to have any effect.
And I can't see any connection in the thread you linked to.
No-one there messed up their compass system causing a chaotic flight.
 

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