Naza Home Lock saved me - Lost Control with near fly-away

[plasmo]

I've had about 20 successful flights prior to this, but this time had serious issues flying.
I Flew earlier today without problems, but during this last attempt I nearly lost total control of the quad.

Calibration of compass was performed as usual, with 10 satellites locked on. Everything was green.
Immediately after liftoff, it started to drift away from me (is this toilet bowling?). I tried to manually fly it back to me, but it was drifting towards some large trees, so I was able to use the left stick to gain altitude in order to avoid the trees, but it was still flying away from me.
Luckily, I had NAZA mode enabled and use the HOME lock S2 switch and was able to get the bird closer to me and try to manually land. I was able to get it away from the trees and over the field, but it was still drifting, and fortunately was able to do an emergency landing. Luckily, nothing broke.!!!!!
I was silly enough to test it one more time (but this time only a couple feet off the ground) after recalibrating the Compass and it did the same thing with another emergency landing. Again, I was super lucky and nothing was damaged, only some grass stains on a couple props.
No way I was gonna press my luck again, and so I packed up, and headed home to connect the P2V+ to the computer to recalibrate everything.

Before I go out and test it again after recalibrating everything with the Assistant, has anyone else had this happen to them, and what happened??? thanks

(View the video on a Computer to see the annotations on the screen...mobile devices won't show it)

[youtube]http://www.youtube.com/watch?v=1U7KjHcBO7I[/youtube]

 

[EMCSQUAR]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

First thing I noticed in your video you launch off a large metal - man hole cover. Metal & compass' not a good combo. In the assistant software -> Tools, do an advanced IMU calibration and make note that your compass #s are below 1800 (my bet is they are currently over that)

 

[plasmo]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

First thing I noticed in your video you launch off a large metal - man hole cover. Metal & compass' not a good combo. In the assistant software -> Tools, do an advanced IMU calibration and make note that your compass #s are below 1800 (my bet is they are currently over that)

thanks, I hope it's just the compass that needs calibrating.
I've launced from the same location many times before without problems, but obviously won't be launching from any more manhole covers again.

 

[4wd]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

Connect it to the assistant and do a full IMU calibration even if it says it's not needed.

 

[plasmo]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

After looking at other cases similar to mine, I'm thinking that this is the Toilet Bowl effect. I saw others having the same problem when lifting off from a metal table...


Sent from my iPhone using Tapatalk

 

[BlackTracer]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

That looks like you were in atti mode when you took off. Which is possible if you mistakenly left your S1 in middle after the compass cal. Why are compass cal-ing as usual? This leaves you prone to leaving that S1 in the wrong position as well as making a mistake during cal. I fail to see why you would cal every time. This is unnecessary and probably led to what happened. I wonder if you unknowingly took off in atti then when the craziness started you instinctively switched S1 up with s2 down which saved your ***. Fly safe!!

 

[dragonash]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

that looked like a MASSIVE TBE.

A "mistake" (I'm using the word loosely as its not a must do thing) I noticed is that you immediately fly right up into the air.

When I first take off, I let it hover for about a minute. I test out all the directions, yaw, pitch etc etc. Like let it all settle in first, just in case anything weird happens, it will be lower to the ground and maybe I can grab a leg if needed.

 

[BlackTracer]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

Does TBE auto rotate the yaw? Cause that's what I see is the thing drifting and the circles induced by yaw. So as it's drifting away he is trying to control it manually as he has stated. Surely he was trying to turn it around with yaw. It looks a lot like IOC off and atti on drifting and circling with the wind. I have been wrong before.

 

[plasmo]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

Thanks for the replies. I am positive it was NOT on Atti mode as I was very careful about this. Plus I repeated everything again and the same thing happened.

I agree with liftoff and hover, and normally do this...I was trying to get a video effect of a quick liftoff for the purposes of this flight so normally I don't liftoff so fast and high.

I haven't had time to recalibrate yet but will post my findings afterwards.

 

[mtpisgah]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

i have no ideas i,m just new w/ this phantom machine and getting some info. too.....but, please change your 4 blades before you fly again, thanks.

 

[plasmo]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

First thing I noticed in your video you launch off a large metal - man hole cover. Metal & compass' not a good combo. In the assistant software -> Tools, do an advanced IMU calibration and make note that your compass #s are below 1800 (my bet is they are currently over that)

You are right that my Compass MOD is way too high. It was 1999. See pre-calibration screenshot.

Even though the Assistant says I do not need calibrating, I did it several times (Advanced Cali)... but despite this,
I can only get the Compass MOD to around 1970 and it won't go below 1800. Should I keep calibrating over and over???

Also the Assistant keeps popping the window that the unit is too hot, and need to cool down to calibrate, even when I just turned it on about 2 minutes ago.


ADDENDUM2: I tried moving the P2V+ off the wooden table to a different location, and the Compass MOD immediately goes to 1200. Now I don't know which number to trust... I move it back to the table and it goes to 1900s.

 

[plasmo]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

I tried calibrating IMU on two different machines in different locations.

Depending on where the Phantom is sitting, I can get normal values around 1200, but if I move it to another location, it can go anywhere from 1900s to even 2200. Doing the advance calibration doesn't seem to change much, at least on the Assistant.

 

[Mori55]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

The to hot warning is just a bug, don't worry about its well known . Disregard it.

 

[XL-Studios]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

Close call mate!
NEVER EVER take off from a metallic manhole again! It WILL mess up your compass. Same thing for taking off from a car hood or roof etc. (Seen far too many do this with bad results) Get you compass degaussed, calibrated and you should be ok. And one more thing, don´t shoot off to the sky right away, let your bird hoover for some 10sec at 2m to see all is ok and stabile before exploring further. OK!?

 

[plasmo]

Yes I'm thankful that my bird is in one piece still.
I'm surprised that the instructions do not stress avoiding metal even more. I'm even more surprised that Colin's DJI showed a video of him calibrating and working his quad on a metal table in one of the DJI videos I saw

The more I think about this, I'm agreeing that it was the metal manhole that messed up my compass and caused the TBE. I flew from this area numerous times before but now recall taking off from the grass all those times... and only landing on the manhole once before. (Sorry can't make that sentence sound clear without making it sound funny)

 

[XL-Studios]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

Yes I'm thankful that my bird is in one piece still.
I'm surprised that the instructions do not stress avoiding metal even more. I'm even more surprised that Colin's DJI showed a video of him calibrating and working his quad on a metal table in one of the DJI videos I saw

The more I think about this, I'm agreeing that it was the metal manhole that messed up my compass and caused the TBE. I flew from this area numerous times before but now recall taking off from the grass all those times... and only landing on the manhole once before. (Sorry can't make that sentence sound clear without making it sound funny)

Yes the metal table is kind of odd but Colin did stress that "-you wanna do this in a open space without any magnetic interference..."
I had my compass messed up by a typical teak garden table that was actually on a metal frame. We live we learn...

 

[plasmo]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

I'm still waiting for better weather to test out my bird after the Advanced Calibration... it's been too windy last couple days.
I have a feeling I will be calibrating more often after this experience...and mindful of where I set down the quad during transportation

 

[plasmo]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

Followup:

After doing IMU advanced recalibration (the compass is still all over the place depending on which direction i'm pointing the quad during calibration), I took it out for a test flight... and it works ! Hovers like it should again. WHEW!
I'm sure it was the metal manhole that caused the TBE.

 

[plasmo]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

Now that I know things are working properly, I made a new video of the TBE,
but this time with annotations of what was going on, and some music...to add to the drama lol. enjoy.

[youtube]http://www.youtube.com/watch?v=01rZ3oIHgyQ[/youtube]

 

[offtosleep]

Re: Naza Home Lock saved me - Lost Control with near fly-awa

Thanks for sharing! And keeping us updated.