KK 2.1 Problems

Flying Zayin

Junior Member
Power sensor?

Hi mate, i made this diagram of a power distribution for a tricopter hope it helps ;)
Sorry for such a question (still at the stage of 'going to order' the board while making the copter at slow speed):
There is a XT60 thing in your diagram, looks like power sensor or something of a kind; does it come together with the board or does it have to bought separately? Where do you connect the voltage gauge on the board?

Sorry guys :confused: I promise my questions will be more sophisticated next time :rolleyes:
 

xuzme720

Dedicated foam bender
Mentor
The XT60 is a battery plug. You can substitute any plug you desire as most pilots standardize to one type of plug for convenience. Deans and XT60's are probably the most common, but whatever you can get easily and will work with your current draw will be fine.
common-battery-connectors_1359094767387.jpg
 
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Flying Zayin

Junior Member
The XT60 is a battery plug
Oh boy. :eek:
Shame on me.
Thank you for such a detailed reply. Of course I know these plugs, just my mind was working in a different direction - I kept on thinking that was sort of a current sensor or alike separate unit.
So where does it connect on the board? Blast, I have already soldered the 'harness' for 3 escs and have no intention to undo it and solder again... will have to find an elegant way around.
 

xuzme720

Dedicated foam bender
Mentor
If you have the harness built, you should already have the connections! The FC boards are powered through the ESC's BEC. No need for additional connections unless you want to use a separate BEC.
 

Flying Zayin

Junior Member
Confused now.

If you have the harness built, you should already have the connections! The FC boards are powered through the ESC's BEC. No need for additional connections unless you want to use a separate BEC.
Wait a sec. Esc feeds the board with 5...6 V, right? If so, how does the board read the full batt voltage? It should be taken off the harness some place and fed into the board's voltage gauge (not sure where it is yet). Might be those two prongs right below the beeper connector.
What I am wondering about is not how to power up the board, but how to feed in the voltage so the board takes care of alarming me on low V.
 

xuzme720

Dedicated foam bender
Mentor
Ahhh. yes. you'll need a 2 prong connection for the battery alarm. Sorry, that was my misunderstanding.
A JST should fit the bill if you have one handy.
What I did to power my FPV transmitter was to build a power takeoff plug with 2 battery connectors. I use Deans so I just took a male and a female and soldered them together. I can add or remove wires easily since all I have to do is take the heatshrink off the plug and add or remove wires, then reapply more heatshrink.

This is a Deans to XT60 but if you think of 2 deans you should see what I mean. Same thing but with a JST soldered in there as well, heatshrink over both Deans plugs.
20110331164238.jpg
 

xuzme720

Dedicated foam bender
Mentor
I found a picture that better describes what I did. This is a manufactured unit, but it's very easy to make your own...
Etap_t_deans.jpg
 

DDSFlyer

Senior Member
Ahhh. yes. you'll need a 2 prong connection for the battery alarm. Sorry, that was my misunderstanding.
A JST should fit the bill if you have one handy.
What I did to power my FPV transmitter was to build a power takeoff plug with 2 battery connectors. I use Deans so I just took a male and a female and soldered them together. I can add or remove wires easily since all I have to do is take the heatshrink off the plug and add or remove wires, then reapply more heatshrink.

This is a Deans to XT60 but if you think of 2 deans you should see what I mean. Same thing but with a JST soldered in there as well, heatshrink over both Deans plugs.
View attachment 21059

That's an awesome idea. I made my wiring harness with 3 ESC's and 3 JST connectors to power everything (voltage sensor, LED's, and FPV - in the future plans)
 

Cyberdactyl

Misfit Multirotor Monkey
I'm SO getting into Steveis' firmware on my hex, I ordered another KK2.1 to try on a radical tricopter design I want to do.

I wanted the 'exact' same KK2, but it's gone from the lineup, so I ordered the KK2.1.5.
 

xuzme720

Dedicated foam bender
Mentor
The 2.1.5 is the same except for the markings they added to the board so there is less confusion. Should be no issue using the same firmware.
 

Flying Zayin

Junior Member
Tricopter tail servo behaves weird at bench test

Guys any idea why this can happen?

I'm doing bench tests of my new tricopter a la D. Windestal.
KK 2.1.5 with Steveis KK2.1 V1.15S1 FW.
Tail rotor goes clockwise.
No mixes on radio so far.
Stick moves cause servo deflection in correct direction.

Problem:
- On turning on the motors tail servo slowly goes to either side (most often to the left if seen from the tail side).
- It doesn't go all the way; usually to some 30 degrees tilt, and then stops.
- If copter is turned around, servo works to compensate for the turn in correct direction.
- Tilt speed or angle or side to which servo tilts the motor do not depend on motor revs.
- While servo drifts slowly, it springs back in upright position immediately at throttle off.
- Increasing servo filter value from default 50 to ~75 hardly has any impact at all, after 75 servo starts reacting to stick input slowly and reluctantly while drift decreases only slightly. At 100 drift stops, but so does the servo itself - it ceases to react to stick input altogether.
- When servo drift reaches its end point it is possible to return it to upright position with trim on the radio, HOWEVER it is hard to do as servo tends to go past the trimmed in value (i.e., if it drifted to the left, and I trim it to the right, then it goes way too far to the right, then I trim it back to the left, and so after several minutes trying I finally make it vertical). Trims do NOT retain it from drifting again on next throttle up.​

Small video about it is here

Please come down with your advice and suggestions. This is my very first copter (I have flown planes for some time though). I'm pretty sure there are no serious assembly flaws or wrong mixes (as I said there are no mixes at all on radio side).

Thanks a lot.
- Mark -
 

FinalGlideAus

terrorizing squirrels
Simple answer is, don't worry my young apprentice ;). That's not a problem.

The KK2 is doing it's thing trying to stabilize the tricopter but doesn't know it's still attached to the ground or that there no props attached. You will also find that the motors will spool up on the ground if left at a low throttle. Once airborne all will be good.