Invalid Battery/Abnormal Battery Communication Diagnosed

[happydogs]

I had an earlier post about this. Phantom Vision that would, on and off, flash abnormal battery communication, fly with caution and invalid battery signal.

I ziptied the bird to an outside table so i could "work" on the battery while props spinning, etc waited till i got invalid battery signal or abnormal communication signal. reached under props (easy to do since it was on small diameter table, and pressed battery "in" at different angles. when i press firmly from the SIDES of the battery, the battery signal went away.

thus, clearly, the problem must originate with contacts. this is not a new finding, per se, but i think i've confirmed that issue for my situation.

so, how to fix? solder a tiny drop on the contacts that meet the spring loaded pins? solder a tiny amt on the pins themselves?

trip the plastic collar on the battery so that it will, hopefully, seat deeper?

run strong duct tape around battery to seat it more firmly?

 

[LeoS]

Do you have more specific diagnosis?
Do the spring-loaded pins return to their original position after depressed? Do they wobble?

Could it be because of temperature change?

 

[Pull_Up]

...and which contacts? Spring pins or the main spade connectors for power.

Interesting, though, and would perhaps explain why this sudden power loss seems to happen to people in cold conditions - uneven contraction of various parts in colder conditions?

 

[happydogs]

good questions...here's what i see...the spring loaded pins do return to their normal position. but, following the suggestion of another post, i did some measuring and what i'm finding is that the spring loaded pins just barely barely make contact with the flat circular contacts on the battery.

 

[LeoS]

Interesting, though, and would perhaps explain why this sudden power loss seems to happen to people in cold conditions - uneven contraction of various parts in colder conditions?

Yeah, that's what I'm getting at... since this is a new design, maybe they haven't tested it enough in different climates.

 

[Pull_Up]

If the tolerance on the data pins making contact are now that tight then cold conditions could certainly make that shaky, although given the last firmware update that shouldn't affect power, only provoke the caution message. Are we now suspecting the spade connectors that carry main power?

 

[Migmon]

have you contacted DJI? I had a battery issue today and sent them a mail

 

[LeoS]

If the spade connector gets disconnected, the Phantom would simply lose power and plummet from the sky, no?

I wonder how brief of a disconnection (from the main power) can it 'survive' before resetting the IMU.

 

[Migmon]

If the spade connector gets disconnected, the Phantom would simply lose power and plummet from the sky, no?

I wonder how brief of a disconnection (from the main power) can it 'survive' before resetting the IMU.

I dont think its the spades coming undone its those two pins below the spades inside the vision that are not making a good connection

I also think if the spade came undone the PV would probably remain off or go through its power on process.... not sure if it would survive haha

 

[Pull_Up]

Migmon that's been a known issue from early on, a firmware update meant that if the data pins lose connection the Vision won't suffer power issues, etc, you'll just get an advisory warning on the app and will be able to continue to fly...

 

[happydogs]

ok, yes, i understand that this has been a "known" issue but i can't always fly as normal...sometimes power goes to be reduced because it says that i'm out of battery, which i'm not. that is, the phantom starts to land itself wherever it is.

sometimes, with the invalid battery signal, it won't throttle up and take off.

now, granted, this was before the update of the last couple of days.

BUT,

how can i remedy this? i'm thinking of maybe soldering a tiny bit to the end of the prongs...or maybe drop a tiny drop on the circular contact points to, in effect, "raise them".

thoughts?

 

[happydogs]

this link will take you to an extensive discussion (with pic) of the problem.
http://www.rcgroups.com/forums/showpost ... tcount=695

 

[garygid]

One case caused by the faulty data contacts/connections in normal flight
made the P2V stop operating properly and crash. That case should never
have even been there.

Presumably it was patched, but there could easily be other similar cases
that remain unfixed. There should be no case, when the motors are On,
that battery data loss should cause dangerous, unannounced behavior.

However, during flight (discharge of the battery), one must be able to get
all three cell voltages, not just the pack voltage, to determine low battery
warnings, since one cell might be low and require initiating end-of-flight
procedures.

The primary cause, poorly placed, dimentioned, or manufactured contacts
or pins, should also be fixed, perhaps by offering a fix-kit or service.
I intend to measure and "fix" my contacts.

 

[skyhighdiver]

wish dji would make a official statement and what the fix will be.
seems to be alooooot of these battery issues and with a new product you think a quick fix would be in order
especially since it sounds like its not a actual power issue but a communication pin issue.
simply don't allow the controller to shut down because of lost communication with battery

 

[MrFlats]

I've experience the above issues too. Twice! Both times it was very cold outside. Seeing other experience this too in the cold, we may have a commonarity here. Also, has anyone try iced powering up the p2v with the pins blocked with Saran plastic wrap, you k ow for sandwiches as to mimicking the problem?

 

[mrfun]

Got this thread from a search. About flight 40 - my vision did an autoland for no apparent reason. Today (about flight 50) I was flying on the same battery that did the autoland (I marked it) - and my wife was watching telemetry on the ipad. I'm about 400 feet up and 900 feet out over woods and she says that she just flashed a message "abnormal battery communication". I started home immediately. I got it back to me and was hovering at about 40 feet and testing controls and all looked normal. She said it flashed the message briefly twice (when she told me about it) then went back to normal. I hovered for a minute to see if it doing an autoland and it was not. I then started to climb and at around 90 feet - it just fell out of the sky.
No autoland, no message, no nothing. Landed on dirt but landed on one arm - broke both top and bottom shell as well as the prop...and broke a leg off the camera mounting bracket.
I read about the initial battery problems and uploaded the firmware update...thinking any battery communications issues would cause an autoland.

I love that machine. Its like having your favorite dog run over by a truck...

What do I do? Is this a warranty claim? If not - is this kind of damage something that someone that's not an electronics guy can fix?
If anyone is there with advice - I need it.

 

[happydogs]

Got this thread from a search. About flight 40 - my vision did an autoland for no apparent reason. Today (about flight 50) I was flying on the same battery that did the autoland (I marked it) - and my wife was watching telemetry on the ipad. I'm about 400 feet up and 900 feet out over woods and she says that she just flashed a message "abnormal battery communication". I started home immediately. I got it back to me and was hovering at about 40 feet and testing controls and all looked normal. She said it flashed the message briefly twice (when she told me about it) then went back to normal. I hovered for a minute to see if it doing an autoland and it was not. I then started to climb and at around 90 feet - it just fell out of the sky.
No autoland, no message, no nothing. Landed on dirt but landed on one arm - broke both top and bottom shell as well as the prop...and broke a leg off the camera mounting bracket.
I read about the initial battery problems and uploaded the firmware update...thinking any battery communications issues would cause an autoland.

I love that machine. Its like having your favorite dog run over by a truck...

What do I do? Is this a warranty claim? If not - is this kind of damage something that someone that's not an electronics guy can fix?
If anyone is there with advice - I need it.

I dunno what to say...let's stay in touch...supposedly my bird is now at the dji los angeles repair center. i'll start checking thurs afternoon or fri. seems like our problems are very similar.

 

[mrfun]

thanks for the quick response....did they repair yours under warranty?

 

[iDrone]

About flight 40 - my vision did an autoland for no apparent reason. Today (about flight 50)... (it) just flashed a message "abnormal battery communication"... She said it flashed the message briefly twice... I then started to climb and at around 90 feet - it just fell out of the sky... What do I do? Is this a warranty claim?

DJI's manual & firmware release notes tell us if you're running v1.08 firmware Vision will initiate an auto landing if it sees less than six sats for 20 seconds, or the battery drops to factory programmed warning level #2 (15% remaining), or the Vision detects a battery pack voltage of less than 10.65 volts. It should -not- drop from the sky.

When it dropped, do you recall whether all motors stopped and it "fell" silent? Was it still powered when you found it on the ground? Were all the NAV beacons out when it was dropping? Or was it still lit & powered? One nicely documented case found a poor solder joint on one of the ESC's which in-turn intermittently cut power to one of the motors. You can read about it here:
http://www.phantompilots.com/viewtopic.php?f=7&t=5576&p=42177#p41942

Myself and a few others have experienced a few odd "Low Battery" warnings accompanied with sudden drops in the battery gauge followed by initiating an auto landing when throttling up (coincidentally when flying in colder ambients of 45°F or less). So far this been attributed to a weak or bad SmartBattery and some of us are awaiting replacements.

Geert and others have recommended using contact cleaner on both the battery's data pins & DC terminals suggesting the DC power connection may be intermittent. If they're right, I can see the Avionics blackout w/insufficient time to reboot & recover even if power is restored. I can also see erroneous battery gauge readings if the connection isn't delivering full current & voltage to the PV.

As for what you can do... you pretty much did it, copy what you wrote above and send it to your dealer + file a Problem Report on DJI's website:
http://www.dji.com/tech-support/report-problem/

iDrone

 

[happydogs]

after it started to auto land, i increased throttle and began to bring it back...it was about two house yards away. At 20 ft, on the way back, the motors STOPPED! boom! stopped! and it fell like a brick. the klaxon went off just after the motors cut out.