Mavic 3 Flyaway

[LA 2020]

I have an ongoing discussion going on DJI who are telling me that a loss of control of my Mavic 3 while using the DJI RC PRO was because I changed the Home Point to a position a mile away from me before activating the Return Button. The Home Point did in fact change 2 minutes I took off, but my research shows me that the only way that you can change your Home Point to a point that is not either the Controller or the Aircraft is by activating option 3 after going into Change Home Point, and dragging the map.
So far DJI are saying that the Home was changed by Pilot, when at the the time I had not yet learned to follow the steps to do that.
I have asked them to explain to me how the Home Point could change by itself and that if it did that, I have to assume that there is either a hardware or software issue with the DJI RC PRO. Fortunately I eventually found the Craft in thick bush using Find my Drone. This was a very dangerous incident regarding flying over homes and freeways where I would not normally go.
Any Ideas about this anybody ??

I read about so many problems with the M3, I think they did not test it properly before putting it on the market

 

[slup]

What is the reason for the increasing difference between the IMU and the VPS altitude in the Flight logs ?

The measurements are done by 2 different systems relative different thing's ...

-The IMU altitude is relative the recorded HP & measured by the barometric sensor.

-The VPS altitude is made by the VPS sensors on the belly of the drone & they measure the distance to ground directly under the drone ... and works reliable between 0,5-30m.

 

[sar104]

I read about so many problems with the M3, I think they did not test it properly before putting it on the market

That's mostly because problems are what get posted about. Exactly the same thing gets said with every new model.

 

[vlieg]

What is the reason for the increasing difference between the IMU and the VPS altitude in the Flight logs ?

Answering my own question: Today I took the Flyaway Mavic 3 (Now Found) for a flight but kept it close to me and definitely did not use the Return Home function, which had previously made the Mavic 3 take off. I suddenly noticed that when the craft was facing me, the triangular GPS widget was facing away from me. I rotated the craft and the widget also rotated on the DJI RC PRO screen but it was always facing the wrong way. I then realized that if I activated Return to Home, the craft would fly away in the wrong direction as it did when it was got lost. When I tried to update the HP the controller signaled that it could not do that unless I turned on location services ??
When I got home I went into settings and saw that Wi Fi was off and Airplane Mode was on. I turned off airplane mode, turned on WiFi and did an IMU reset and Compass reset. I then observed the triangle was facing in the same direction as the craft and rotated in the same direction as the craft.
I don't know if this is all just coincidence but I am quite confident that if I used the Return To Home function at this point, the craft would return to the controller as the Home Point.
I did not check these settings when I first unpacked the new DJI RC PRO and I wonder if they ship these units with Airplane Mode switched on.
I would welcome comments because I am sure that some of the pilots, whom are more experienced than me, would make more sense of this than I can. Oh yeah I then did a reset of the RC PRO.

 

[Meta4]

I would welcome comments because I am sure that some of the pilots, whom are more experienced than me, would make more sense of this than I can.

There'a a lot of confusion in your post.
I'll see if I can clear some of it up.

I kept it close to me and definitely did not use the Return Home function, which had previously made the Mavic 3 take off.

RTH did not make your drone "take off".
You reset the home point while the drone was in RTH.
That caused the drone to fly towards the new home point that you had set (2000 ft away from where you were).

the triangular GPS widget was facing away from me.

The "triangular GPS widget" is an icon representing your drone.

I rotated the craft and the widget also rotated on the DJI RC PRO screen but it was always facing the wrong way.

What do you mean by the wrong way?
If the actual drone is facing east, the icon should also be pointing toward east

I then realized that if I activated Return to Home, the craft would fly away in the wrong direction as it did when it was got lost.

Why would you think this?
btw, it's incorrect.

When I tried to update the HP the controller signaled that it could not do that unless I turned on location services ??

If you tried to reset the home point (why would you need to?) to the current location of the controller, the app has to have access to the location data from your phone or tablet to do that.

When I got home I went into settings and saw that Wi Fi was off and Airplane Mode was on. I turned off airplane mode, turned on WiFi and did an IMU reset and Compass reset.

If you recalibrated the compass and IMU in your drone, that was completely unnecessary.
Don't mess with them.

I then observed the triangle was facing in the same direction as the craft and rotated in the same direction as the craft.

I don't know if this is all just coincidence but I am quite confident that if I used the Return To Home function at this point, the craft would return to the controller as the Home Point.

It's not coincidence, it's confusion.
You need to learn more about how your drone works and not assume that you already do.

I did not check these settings when I first unpacked the new DJI RC PRO and I wonder if they ship these units with Airplane Mode switched on.

It makes no difference whether airplane mode is on or off (unless you need wifi to download something etc).

 

[vlieg]

There'a a lot of confusion in your post.
I'll see if I can clear some of it up.


RTH did not make your drone "take off".
You reset the home point while the drone was in RTH.
That caused the drone to fly towards the new home point that you had set (2000 ft away from where you were).

The "triangular GPS widget" is an icon representing your drone.

What do you mean by the wrong way?
If the actual drone is facing east, the icon should also be pointing toward east

Why would you think this?
btw, it's incorrect.

If you tried to reset the home point (why would you need to?) to the current location of the controller, the app has to have access to the location data from your phone or tablet to do that.

If you recalibrated the compass and IMU in your drone, that was completely unnecessary.
Don't mess with them.



It's not coincidence, it's confusion.
You need to learn more about how your drone works and not assume that you already do.

It makes no difference whether airplane mode is on or off (unless you need wifi to download something etc).

You said,"If the drone is facing east, the icon should also be pointing east".
It wasn't !! it was at about 45 degree angle to the direction that the craft was facing. Confirmed by 2nd observer.

You said, that I must not assume that I already do know how my drone works.
This is an assumption on your part.
I don't assume that I already know how my drone works and I thought that I made that clear by asking the advice of more experienced Pilots.

Also someone has yet to explain to me how I was (able ??) to change my HP to 2,000 feet away from me without going into the Update Home Point setting.

 

[Meta4]

You said,"If the drone is facing east, the icon should also be pointing east".
It wasn't !! it was at about 45 degree angle to the direction that the craft was facing. Confirmed by 2nd observer.

I'm sorry, but there is so much confusion in what you say that I cannot be sure of anything you write.
If the drone icon was facing anywhere but the way the real drone was facing, the flight would have been uncontrollable and ended quickly.
That didn't happen, so I can tell that the drone and icon were pointing the same direction.

You may be confused by the orientation indicator because it normally shows the direction you are facing as up and N, E, S, W rotate about the home point as you turn.
In this example, I am facing South, the drone is to my south and pointing toward me.

If I was to turn, the drone icon wouldn't stay at the top of the circle, but the whole circle, the drone icon and North indicator would rotate around me as I turned.

I don't assume that I already know how my drone works and I thought that I made that clear by asking the advice of more experienced Pilots.

You did and what you writes makes that clear.

Also someone has yet to explain to me how I was (able ??) to change my HP to 2,000 feet away from me without going into the Update Home Point setting.

Either:
1. you have the first incident where the drone's homepoint magically changed by itself, or
2. you set a new home point by dragging to a new one on the map (without even knowing it).
As I've examined the data from hundreds of flight incidents and never seen or heard of a home point changing by itself, I have to assume that #2 is the explanation.

Unfortunately the recorded data does not show how it was done, but it does show that it was done.

 

[vlieg]

I'm sorry, but there is so much confusion in what you say that I cannot be sure of anything you write.
If the drone icon was facing anywhere but the way the real drone was facing, the flight would have been uncontrollable and ended quickly.
That didn't happen, so I can tell that the drone and icon were pointing the same direction.

You may be confused by the orientation indicator because it normally shows the direction you are facing as up and N, E, S, W rotate about the home point as you turn.
In this example, I am facing South, the drone is to my south and pointing toward me.

If I was to turn, the drone icon wouldn't stay at the top of the circle, but the whole circle, the drone icon and North indicator would rotate around me as I turned.




You did and what you writes makes that clear.

Either:
1. you have the first incident where the drone's homepoint magically changed by itself, or
2. you set a new home point by dragging to a new one on the map (without even knowing it).
As I've examined the data from hundreds of flight incidents and never seen or heard of a home point changing by itself, I have to assume that #2 is the explanation.

Unfortunately the recorded data does not show how it was done, but it does show that it was done.

I am sorry that my attempts at describing the situation are so confusing.
This is due to my inexperience with all of this. I am a Newby and trying to figure it out.

I guess that I have to accept that due to my inexperience, I must have dragged the the home point on the map without knowing it. There must be a way of my having done that without going into the settings(Change Home Point) because I don't believe that I could have taken multiple steps unconsciously. I had recently launched the drone in the air at that point so I would not have moved from the take off screen.

As far as the drone icon is concerned, I brought the drone literally face to face with me and the other observer. I would have expected the Icon to be pointing towards me in the same way that the icon is pointing to "H" in your diagram above. It was not pointing in the same direction as the drone was, towards us, but was pointing in a direction at a 45 degree angle to us. I know that it sounds weird but I have flown a Phantom 3 and Air2s a few times before and this has never happened. In fact with the Phantom 3, I used the icon to know which way the craft was facing if it was a distance away and this was a great help.

Since I recalibrated everything the drone icon is facing in the same direction as craft. So if the craft were coming towards me the icon would now be pointing towards me.

 

[Meta4]

I would have expected the Icon to be pointing towards me in the same way that the icon is pointing to "H" in your diagram above. It was not pointing in the same direction as the drone was, towards us, but was pointing in a direction at a 45 degree angle to us.

It won't matter if the drone was out at 45°, if it was pointing towards the centre (Home)
That's just an indication that the compass in the phone or tablet isn't reading properly due to magnetic fields in the controller.
It's what direction the icon was pointing that matters.
That is much more important that where it is on the circle.

Since I recalibrated everything the drone icon is facing in the same direction as craft. So if the craft were coming towards me the icon would now be pointing towards me.

Recalibrating anything on the drone won't have made any difference.
It was all calibrated just fine, if it wasn't you'd have known because it wouldn'ty have flown properly..
You really don't need to recalibrate anything - just leave that alone.

 

[slup]

Answering my own question: ...

You're very confusing here ... you reply to your own question & saying that you answer your own question, but doesn't mention anything about heights in you long & again confusing answer ?

You got the answer regarding the IMU & VPS height already in post --> #42

... I suddenly noticed that when the craft was facing me, the triangular GPS widget was facing away from me. I rotated the craft and the widget also rotated on the DJI RC PRO screen but it was always facing the wrong way...

In post --> #33 ... in the "Newbie card" there I wrote:

Preferably power on the drone keeping it horizontal in your out stretched hand (without watches, rings or other magnetic objects) … once the live view have turned up in your mobile device you can put it on ground for take-off. (This supports the point below …)

Before take-off ALWAYS ... add in one very easy check to avoid a really scary event coming from accidentally launching from a magnetic disturbed place with following flyaway at height in an uncontrollable circular or straight flight path. After powering on your drone, connected to your RC/app & placed it in the take-off spot ... but before lift-off, ALWAYS check that the drone icon on the map in your app is pointing equal in relation to other objects in the map as the drone does in reality ... if not, abort launch attempt, POWER DOWN & move away, power up again and repeat.

To give you more here I've attached a picture here below to perhaps easier show you what I mean... (click on it to make it larger)


If the drone icon on the map isn't pointing in the same direction relative map object like it does in reality (like that road in the pic above)... it means that your drones compass was magnetically interfered when you powered your drone on... that in turn made your IMU to align to that wrong compass direction. This will turn out to be disastrous when you get airborne & your drone needs to hold position for the first time (for instance needs to hold position against wind). When this happens your drone will use the wrong motors to counter the wind ... & the positional error will be even larger ... & you drone will try again, & again but fails as it uses the wrong motors & your drone will fast fly away.

But that wasn't what happened in your other flight ... there you made it fly away from you as you fought a autolanding & nailed the throttle & elevator to max.

...When I tried to update the HP the controller signaled that it could not do that unless I turned on location services ??
When I got home I went into settings and saw that Wi Fi was off and Airplane Mode was on...

If your device is in airplane mode no device (RC Pro) GPS position will exist ... if then trying to set the HP to the device location it wont work ... as your device doesn't have a position. That's why the app advice you to turn on the location services.

 

[life.in.nb]

There is a problem with the current firmware that the Mavic 3 with the RC Pro is taking about 2 or more minutes to acquire the satellites. If you don't wait until you hear the voice "the home point has been updated" and you start flying away then the home point will be set in the trajectory of your flight once the drone acquire about 11-13 satellites. This can set your home point far from home. You can set manually the home point back to your location or just wait until the home point is set before you move the drone.

It's not just with the RC Pro. My base controller that came with the normal version, takes 3 or 4 mins to acquire satellites. It's BAD.

 

[zeusfl]

It's not just with the RC Pro. My base controller that came with the normal version, takes 3 or 4 mins to acquire satellites. It's BAD.

That is right. The problem is not the controller itself. Is the M3 firmware.

 

[JohnC]

It's not just with the RC Pro. My base controller that came with the normal version, takes 3 or 4 mins to acquire satellites. It's BAD.

Pretty certain the standard controller does not contain a GPS it gets its GPS data from your mobile device.

 

[life.in.nb]

Pretty certain the standard controller does not contain a GPS it gets its GPS data from your mobile device.

i meant the time it takes the DJI mavic 3 itself to get the gps lock (not the controller). sorry should have clarified =)

 

[vlieg]

You're very confusing here ... you reply to your own question & saying that you answer your own question, but doesn't mention anything about heights in you long & again confusing answer ?

You got the answer regarding the IMU & VPS height already in post --> #42


In post --> #33 ... in the "Newbie card" there I wrote:

Preferably power on the drone keeping it horizontal in your out stretched hand (without watches, rings or other magnetic objects) … once the live view have turned up in your mobile device you can put it on ground for take-off. (This supports the point below …)

Before take-off ALWAYS ... add in one very easy check to avoid a really scary event coming from accidentally launching from a magnetic disturbed place with following flyaway at height in an uncontrollable circular or straight flight path. After powering on your drone, connected to your RC/app & placed it in the take-off spot ... but before lift-off, ALWAYS check that the drone icon on the map in your app is pointing equal in relation to other objects in the map as the drone does in reality ... if not, abort launch attempt, POWER DOWN & move away, power up again and repeat.

To give you more here I've attached a picture here below to perhaps easier show you what I mean... (click on it to make it larger)

View attachment 142123
If the drone icon on the map isn't pointing in the same direction relative map object like it does in reality (like that road in the pic above)... it means that your drones compass was magnetically interfered when you powered your drone on... that in turn made your IMU to align to that wrong compass direction. This will turn out to be disastrous when you get airborne & your drone needs to hold position for the first time (for instance needs to hold position against wind). When this happens your drone will use the wrong motors to counter the wind ... & the positional error will be even larger ... & you drone will try again, & again but fails as it uses the wrong motors & your drone will fast fly away.

But that wasn't what happened in your other flight ... there you made it fly away from you as you fought a autolanding & nailed the throttle & elevator to max.

If your device is in airplane mode no device (RC Pro) GPS position will exist ... if then trying to set the HP to the device location it wont work ... as your device doesn't have a position. That's why the app advice you to turn on the location services.

I just want to thank you guys because I have realized that you guys are totally correct in your analyses of my flyaway. I did hit the return button twice. Thanks for the schooling and sorry about my confusing ramblings.

 

[maelstrom]

If your device is in airplane mode no device (RC Pro) GPS position will exist

I'm confused here. If I put my iPhone into Airplane mode and use any GPS-dependant app, the GPS symbol still appears at the top of the phone display and my position is reported normally in the app so it's obviously still receiving GPS signals.

 

[Meta4]

I'm confused here. If I put my iPhone into Airplane mode and use any GPS-dependant app, the GPS symbol still appears at the top of the phone display and my position is reported normally in the app so it's obviously still receiving GPS signals.

Airplane Mode shuts down any transmissions from the device, but it can still receive.
GPS doesn't require the device to transmit anything, so is unaffected by switching to Airplane Mode.

 

[BossBob]

Airplane mode stops your phone from sending and receiving wifi and mobile signals and is from an era when aircraft and medical equipment might be interfered with by the transmission.
Why would the reception of gps signal by a phone effect the operation of an aircraft that is probably using the same gps signal to tell where it is?

 

[Meta4]

Airplane mode stops your phone from sending and receiving wifi and mobile signals

Airplane Mode doesn't stop the phone from receiving wifi, just sending.

 

[vlieg]

I was using the DJI RC Pro at the time, not an iPhone, and this was before the recent update. I did not know about the slow acquisition of satellites at the time so I think that I had a weak GPS signal. In addition I hit the return button twice which really messed it up. I did later discover that the RC Pro was in airplane mode but I am not sure that contributed to the flyaway.