Dji WKM kep rotating and crashed

paktazh

Member
I build a Heax rotar with WKM V1 Using T motor 2216-12-kv800 APC prop and T motor 30A Esc with 2 3s battery I was flying it today the led light was flashing normal then it was flashing red in few min but the battery was full it went 20 meter up and going up very steady then when I try to bring it down I noticed that it is kind of rotating and became unsteady and suddenly it crashed to one side destroyed my beautiful $500 gimbal and ... do not know why has any one else had the same issue any one else had the same issue


I do have telemetry system so the voltage was 3.96 for each cell after crash in both batteries so no low voltage involved here what exactly happened when i start to take off it was flying but not going to high and red was flashing and it was kind of landing by itself even the throttle was over the meddle then i put te throttle to 80 then it was keep going up it was very steady in GPS mood but once i try to land still in GPS mode then it it lost the steadiness that it had and not responding to Tx very well it was going to one side and other side and small turn and then crash to one side there was no prop was broken in the air only in the ground I assume that it could be some bug in GPS I am using the GPS that has two black side also I was told that since I use T-motor ESC might need some programming if so do u know how ???
 
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Give it a little more time... others will hopefully chime in.
When you say 3.96V, is that under load, or once you removed them from the aircraft?
Did you have voltage protection turn on and if so, to what values?
Was this your maiden flight so you haven't adjusted gains yet?
What do you mean by a GPS that has two black sides?
(I'm just asking questions to help those that will come along to help.)
 

OneStopRC

Dirty Little Hucker
I might be wrong, but with the new firmware for WKM, if you loose a prop, motor or esc, the unit tries to go into a failsafe which makes the craft spin so you can land it still... not sure if this is what you're referring to?
 

paktazh

Member
3.96 was after the crash so that cannot be the cause since the battery still had power to land regarding the GPS i heard that one of the WKM GPS has a bug mine is version one the two side of the GPS has colored black
 


Dewster

Member
Do you have other equipment running off of your flight batteries? My Y6 had a power hungry video transmitter and FPV camera. My craft weighed just over seven pounds. I was using old lipos. It's the only possible explanation for the sudden drop in power which caused my craft to spin (the bottom props were longer and had higher pitch than the top on my Y6).

I test flew my experimental quad with the same batteries and had the same result. It just dropped from the sky. These batteries were giving me 6.5 to 7 solid minutes of flight time. My crash happened 3 minutes 30 seconds into the flight.

I can only imagine that it was either the age of the lipos or just having too much power hungry devices feeding off the flight battery.

Heres my quasi deceased bird:

http://youtu.be/DaCp1USGAGM


my craft also started a spin, but I think/thought it was due to the bottom props having more pitch than the top. Maybe the low power of the lipo (excessive drain on the batteries) triggered DJI's loss of prop, ESC, motor fail safe resulting in the spin.
 
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tombrown1

Member
V1 GPS is ok. Red flashes mean lost GPS signal. Did you have GPS lock before the flight? Did you try atti or manual before the crash? Most escs you do have to program. Not sure about t motor specifically. You need to set battery type to nicad, fail safe off, high timing, etc... Also need to calibrate escs. Did you calibrate the GPS?

Best,

tom
 

Paktahz, in your telemetry did it say you have GPS or not? If you have the iOSD it will tell you there as well. As Tom said, it may be that you lost GPS to the FC. Last week I had my GPS wire come loose in mid flight and it reverted to ATT mode. (I have since put hot glue to hold the plug in.)
 

paktazh

Member
Do you have other equipment running off of your flight batteries? My Y6 had a power hungry video transmitter and FPV camera. My craft weighed just over seven pounds. I was using old lipos. It's the only possible explanation for the sudden drop in power which caused my craft to spin (the bottom props were longer and had higher pitch than the top on my Y6).

I test flew my experimental quad with the same batteries and had the same result. It just dropped from the sky. These batteries were giving me 6.5 to 7 solid minutes of flight time. My crash happened 3 minutes 30 seconds into the flight.

I can only imagine that it was either the age of the lipos or just having too much power hungry devices feeding off the flight battery.

Heres my quasi deceased bird:

http://youtu.be/DaCp1USGAGM


my craft also started a spin, but I think/thought it was due to the bottom props having more pitch than the top. Maybe the low power of the lipo (excessive drain on the batteries) triggered DJI's loss of prop, ESC, motor fail safe resulting in the spin.


My zippy Batteries are new I use two of them and yes I had my FPV transmitter was connected to one of those batteries so do u think that power discharge was not enogh for motor because of the FPV transmitter and is that why it crashed ? because certenly there was more power in the batteries since each cell was 3.96 after the crash when i tested them
 

paktazh

Member
I no it was all in GPS mood but when i try to land it it got irresponsive and instead of coming down it was going toward left and then suddenly it start bending to one side and crashed you talked about the ESC program how do calibrate the escs ?? I did calibrate the GPS
 

paktazh

Member
Paktahz, in your telemetry did it say you have GPS or not? If you have the iOSD it will tell you there as well. As Tom said, it may be that you lost GPS to the FC. Last week I had my GPS wire come loose in mid flight and it reverted to ATT mode. (I have since put hot glue to hold the plug in.)[/QUOT


But even if it lost GPS it should go to ATI and not crash am I right ? I use quanum telemetry it only show the voltage /
 




Paktazh, sorry, nothing is standing out to me other than the usual precautions and checks we all have to make. Plus, the link you provided does not have a video available. It says it's still in progress.
I'll just throw out some thoughts:
- Are you sure one of your motors or ESCs didn't go out? Even momentarily?
- Have you fire up the hex and verified everything is currently working?
- Are you sure the GPS and IMU all calibrated, positioned, and oriented correctly?
Like I said, nothing in your write-up stands-out as having a problem, but the red flashing should be looked into. It's apparently not voltage, but could be other things.

Hopefully others can chime in.
 

paktazh

Member
Paktazh, sorry, nothing is standing out to me other than the usual precautions and checks we all have to make. Plus, the link you provided does not have a video available. It says it's still in progress.
I'll just throw out some thoughts:
- Are you sure one of your motors or ESCs didn't go out? Even momentarily?
- Have you fire up the hex and verified everything is currently working?
- Are you sure the GPS and IMU all calibrated, positioned, and oriented correctly?
Like I said, nothing in your write-up stands-out as having a problem, but the red flashing should be looked into. It's apparently not voltage, but could be other things.

Hopefully others can chime in.

Thanks but if u use Firefox it will i don't know why it says that with Google browser but play with Firefox browser regarding the motor gone out i did not see that but that could be i did fire up the hex and i hold the hex horizontal then all the motor started couple of them started one sec latter but I found some thing strange when I tried to raise one side of it up and the other side down the side that was down the motor were running and the side that was up the motor was not running i guess may be why but do not know how to solve this issue
[h=2][/h]
 




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