Arducopter is limiting the total power output of my hexacopter to 37 amps when it has the potential for 66amps when at full throttle.

I bench tested many different motor and prop combinations to see which would be the most efficient for my arducopter hex 550.

I decided to use 6 x 1000kv motors with 9x4.7 props which deliver 710g of thrust at 11amps each at max throttle.

Why is arducopter limiting my throttle current draw to 37 amps when the max should be 6motors x 11 amps each = 66 amps.  (see mission planner tuning chart)

I understand that the controller needs reserve power for controlling stablization but 37 amps is only 56% of total power potential that could be used.

I have calibrated my escs many times thinking that was the problem but its not.

When i use my kk2 controller on the same hexacopter i get 52 amp draw at max throttle held down on the bench.

Is there a setting that i need to change to allow the controller to use more potential power.

I want to put more equipment on this craft but it needs more power.

Thanks in advance for your help.

the Chart below shows thrust output for each motor/ prop combination.

I decided to use a 1000kv motor with a 9x 4.7 prop. next chart

This chart is just the 1000 kv motor with 9x4.7 prop  

max thrust was 710 grams at 11amps

I went into the tuning page for Misson planner and see that at full throttle i am only drawing 37 amps for 6 motors.  Hexacopter held down at full throttle on the bench while connected to MP.  the hex draws about 25 amps at hover with no extra equipment on board.

why is arducopter limiting my throttle current draw to 37 amps when the max should be 6motors x 11 amps each = 66 amps.

I understand that the controller needs reserve power for controlling stablization but that is only 56% of total power potential that could be used.

Is there a setting that i need to change to allow the controller to use more potential power.

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Just flashed it again to 3.0.1  and no go ..  same problem..

on another post they said to check..

FS_BATT_VOLTAGE , BATT_CAPACITY 

FS_BATT_VOLTAGE does not exist in 2.7.3 ( but does no 3.0.1  ( set to 0 for disabled)
BATT_CAPACITY Should not matter I would think if its disabled.. ( but I set it to 5100 just for kicks )

But still the same problem..

Ok, I'm fed up with it now.  I'll check into going back to 2.7.3 not sure where to find it but a google search should turn it up easily, I would think. 

I have failsafe disable right now.  I have enough issues to deal with. 

One question, it appears that APM hasn't always done so well with the tricopters.  Will I run into more problems setting my trike with 2.7.3?  Hopefully the fixes for tricopters happened well before that.  Even with the corrections, it's still quite a deal getting a tricopter set up--for me, anyway.  I figured if I could set one up, setting up any other copter would be simple... or simpler. 


It was simple.. but MP does not like the old..  2.7.3 code.. (  someone said try  1.2.55 Mission Planner and that did not work )

have to run but I'll dig up the link to the old code..

thanks..  I hope this works.  I'll let you know how things come out.  

 

There is another alternative that may facilitate some interesting experimentation if nothing else.  It's a off-receiver servo adjuster such as this one here:http://www.servocity.com/html/180o_servo_stretcher.html

A nice looking little device, although I've never tried one.  You can separately over adjust your servo with it, or in this case, your ESC.  If you're already at max with the ESC, forget it.  However, I can see how it would be a short cut to solving a lot of problems regarding certain difficulties a subset of operators are having.  May be only a workaround and lacking the elegance of a true "fix", but it's an interesting approach, I think.  Whether or not it would actually help and not hurt, I don't know. 

Here are the links..

https://github.com/diydrones/ardupilot/releases


https://code.google.com/p/ardupilot-mega/wiki/Programming

follow the link - >  (Downloading and using the APM software)

there was a few change I did to the sketch file.. manually ..

Great!  Thanks for taking the time.  I'll set this up tomorrow and as soon as I have results I'll post them. 

 

Thanks again Luis.

I'm learning a bit more I think ...  haha..

seems if you download the MP  you can pick..  from lower right corner..

  " pick previous version" .  you get some strange "alpha numeric number"  I just picked them at random and you get different version of the software..

It probably will flash it correct vs..  using  --> manual method.. ie - >  ArduPilot Arduino IDE method ..

I may have screwed up .. that's why MP would give errors... when it connected..

I will try this tomorrow also see what happens..

Keverett,

I loaded  2.7.3 again via the MP not the via Arduino IDE software..

Accell Calibration button still did not seem to do anything..

I ended up trying running the setup command via terminal connection.

That seem to work hmm ( after two attempts) or maybe it was the reboot .( unplugged everything and then plugged it in again)


Still get the same error as before..

Luis, had to go out of town for the day n. Postponed the testing to tomorrow. Appreciate the links! More when I get back to my computer
Keith

Question for you Luis...  I'd be very interested to see if the current usage goes up (significantly) if you change the props to couple inches over recommendations.  Do the motors just slow way down to keep pulling only 37amps or does the current draw go up proportionally.  Probably a dim sort of question, but I would certainly like to hear what happens, if you ever try this. 


Not sure I follow your question...

this was all new setup so never tested it on any other Flight Board... 

I did test on some 10 in props..GenFan I think.. it actually seem to fly ok..

I switched to 11in Graupner.. does feel like has more power..

I've never measured the amp draw ..  the major problem was that .. at 3.85v per cell..  motor would slow down so much you had to give 100% throttle to get it to hover.. and just land itself..

One other thing .. with  3.0.1  ( I had  bad YO-YO effect )   could not maintain level flight...

It all seem like a fail safe was kicking in.. ( But I had no fail safe enabled.. ) ..

If I have a break in the weather I will try and fly it tomorrow.. 

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