• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.

KK2.1 Losing Power with GoPro onboard

#1
KK2.1 Cutting Power with GoPro onboard

Ok... So I decided to add the GoPro to the front of my Vtail.

UPDATE
The Crash


After the Crash

IMG_5458sm.jpg

Basically it goes like this:

Put GoPro on; quad stalls after a few minutes (all motors cut, wait a few seconds, they spool up again then cut). The kk2.1 is lit up the whole time.
Is it overheating?, Not enough Amperage on the ESC (20Amp Afro)?

Take GoPro off; flies as normal. I used the same battery. Seems the extra payload is the problem...

UPDATE >> Video after GoPro http://forum.flitetest.com/showthread.php?7432-Bat-Bone-V-Tail-Build-Log/page2

Any Ideas while I set up video for review? This really sucks as I committed to the platform based on FT recommendations, now I fear I may have to buy new stuff... :(

-=unZapped=-
 
Last edited:

baddox

Senior Member
#2
When you add the GoPro, do you do anything to even out the center of gravity, like move the battery backwards? If not, your front motors and ESCs probably have to work way harder than the back ones, which could cause problems.
 
#3
When you add the GoPro, do you do anything to even out the center of gravity, like move the battery backwards? If not, your front motors and ESCs probably have to work way harder than the back ones, which could cause problems.
Yes battery was shifted to the rear of the plate.
 
#4
Are you using the wi-fi on the gopro? It might be interfering with your receiver. Try flying with the gopro turned off but still attached to the frame so you can eliminate that as the cause.
 
#6
Wifi on with the GoPro will elevate the noise floor making it harder for the receiver to discern instructions from your transmitter the further the craft gets away from you. Keep the GoPro off and fly with it on board to see if it helps the situation.
 
#7
Wifi on with the GoPro will elevate the noise floor making it harder for the receiver to discern instructions from your transmitter the further the craft gets away from you. Keep the GoPro off and fly with it on board to see if it helps the situation.
Did you see the second video? I was right above the craft... I will try that tonight.
 
#8
Carefully feel the ESCs when it is doing that issue. If it is so hot you can't keep your finger on it, it might be your problem. They will be warm, but just shouldn't be so hot it is scalding.

Did you make your own power harness, buy a pre-fabbed one, or are you using a distribution board?
 

cranialrectosis

Faster than a speeding faceplant!
Mentor
#9
Are you using a low voltage alarm? After the motors cut out what are the per cell voltages on your lipo?

What is the C rating on your lipo?
 
#10
Carefully feel the ESCs when it is doing that issue. If it is so hot you can't keep your finger on it, it might be your problem. They will be warm, but just shouldn't be so hot it is scalding.

Did you make your own power harness, buy a pre-fabbed one, or are you using a distribution board?
ESC were not hot, I am using a prefabbed harness... After i removed the GP, flight was perfect http://forum.flitetest.com/showthread.php?7432-Bat-Bone-V-Tail-Build-Log/page2
 

cranialrectosis

Faster than a speeding faceplant!
Mentor
#12
10.8 is 3.6 per cell on a 3S.

My ESCs would cut out at that point. If you have an unbalanced cell the motors would cut out.

Are you charging to over 12V on a 3S?
 
#13
That is a valid point. The ESCs may be in a low voltage cut off stage where it reduces available power for a soft-ish landing. @10.8V under load could be down to 9.9V in a second or two; this is known as voltage sag and is misleading because it will rise again after the load has been removed.

I ran into the issue with the voltage alarm going off @10.2V and the copter decending within 15 seconds on my 12A Afro ESCs this past weekend. Charge the battery to 12.6V (full) and give it a go again.
 
#15
10.8 is 3.6 per cell on a 3S.

My ESCs would cut out at that point. If you have an unbalanced cell the motors would cut out.

Are you charging to over 12V on a 3S?
I was never near 10.8... The alarm is set to go of then. I charge to over 12v balanced. I have never had a failure even after alarm was going off. I shot the last video with the same battery after the crash and fix http://forum.flitetest.com/showthread.php?7432-Bat-Bone-V-Tail-Build-Log/page2


That is a valid point. The ESCs may be in a low voltage cut off stage where it reduces available power for a soft-ish landing. @10.8V under load could be down to 9.9V in a second or two; this is known as voltage sag and is misleading because it will rise again after the load has been removed.

I ran into the issue with the voltage alarm going off @10.2V and the copter decending within 15 seconds on my 12A Afro ESCs this past weekend. Charge the battery to 12.6V (full) and give it a go again.
Not sure that this would apply.

Do your ESCs have the SimonK firmware flashed on them?
Yes they do! :)

Is it possible that the added weight could be overheating the KK2.1 itself?

If not, It is likely the WiFi in the GoPro which I will test tonight... inside my house. (softer crashing) I still have my doubts on this...
 
#16
Welp. I would have never thunk it... I hovered the Vtail with the GoPro turned off in my living room much to my wife's dismay and it ran through an entire battery with Zero issues. I was slightly nervous flying this beast in a 7ft X 6ft space... probably really great practice :)

So what did I learn?... Radio interference still sucks despite the advancements in technology over the years. I also learned that the extra weight, while it makes a noticeable difference doesn't really affect it's climbing capability; but sucks the life out of the battery quickly.

My only battery is still charging but, I do plan a flight with the GoPro on with no wifi to confirm my findings.

Thanks and stay tuned...

-=unZapped=-