The new KK2 FC, info and Q&A in first post. Read it before asking a question. - Page 384 - RC Groups
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Oct 25, 2012, 02:19 PM
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gjalbert's Avatar
In principal, the accelerometer data can be double integrated to calculate a position and this used to control an altitude hold function. The problem in real life is that errors build up pretty fast in the integrations so it will drift. Over a short period this can give acceptable performance. Unfortunately, doing this in a platform that can pitch, roll, and yaw, as well as accelerate in three dimensions makes the math quite complicated, and perhaps beyond the KK2's processing capabilities.

Gary
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Oct 25, 2012, 02:54 PM
It's Just a Hobby!
Sudsy's Avatar

Got Parts


Oh Boy!!!
Oct 25, 2012, 04:13 PM
It's Just a Hobby!
Sudsy's Avatar

Not enough power to fly


Well the little saucer doesn't seem to have enough power to fly. I did get a set of three bladed props and have 1000 Mhr batteries to try. The 500 Mhr and the two bladed props just don't cut it.

Sudsy

Never mind. Had number motor running backwards. But now it is very hard to control. It want to go left and yaw right on liftoff. With and without self leveling. I was able to get it to lift though. I'll fool with the P&I adjustments and see if I can get it going.

Sudsy
Last edited by Sudsy; Oct 25, 2012 at 05:21 PM.
Oct 25, 2012, 04:15 PM
safer on the ground
teccer1234's Avatar
this is a video of the first flight with my new build tri using the KK2 1.2v I was surprised that it flew reasonable the very first time, I had to trim the RU a lot to get it to fly straight and when I went to disarm it no joy, I had to reset the trim back to takeoff position to disarm, I then reset the servo/RU central now all's ok on that but as you can see in the vid that as soon as I flicked on the AL it flew backwards and I dropped it before it hit me, I thought I'd switched off the AL for the next takeoff but I hadn't and it still flew backwards, managed to turn the AL off and it flew perfectly again, I'm not sure what to do now to get it to stay level when I switch it on AL,
any suggestions?

ray

leg tri first flight with KK2 board .wmv (4 min 27 sec)
Oct 25, 2012, 04:54 PM
Registered User
Bit of a strange issue here. My KK2 will randomly refuse to control the tail servo on my tri. Happened for the second time today. At first I thought that my tail servo died, and swapped it for a spare that I had lying around, but the new servo refused to operate too. It would initialize fine, and when the KK2 powered up it would center, but when I armed and tried to lift off it does nothing.

I was eventually able to get the servo running by returning the KK2 to factory defaults, and redoing my settings, but a few batteries later, it's doing the same thing again. Factory resets are getting old, so I'm open to any ideas. Two different models of servos have had this problem so far, so I don't think it's an incompatibilty issue.

I'm running software v1.2 by the way.
Oct 25, 2012, 05:29 PM
Registered User
Del-Dredd's Avatar
How are you supplying power to the M2 to M8 connectors?.
Try swapping the power coming in from M2 to M3 ESC.

It could be a flaky BEC within the ESC causing lack of power to the servo, especially if the hinge is binding or got a lot of load on the servo.
Oct 25, 2012, 05:34 PM
Registered User
Quote:
Originally Posted by Del-Dredd
How are you supplying power to the M2 to M8 connectors?.
Try swapping the power coming in from M2 to M3 ESC.
Switching BEC in M2. M3 has another esc with the power disconnected. My understanding is that M2-M8 are bridged, so it shouldn't matter which lead I plug power into, no?

Quote:
It could be a flaky BEC within the ESC causing lack of power to the servo, especially if the hinge is binding or got a lot of load on the servo.
I don't think so...as I said, the servo initializes and holds center fine, it just doesn't get any signals from the yaw gyro, either to compensate for yaw, or in response to my control inputs.
Oct 25, 2012, 05:42 PM
Registered User
WantToPlay's Avatar
Check for a loose rudder cable coming from the receiver. The best way to do that is go to receiver test and wiggle then rudder cable and see if the display says no connection or so. I had the same problem but with ail and the tri flipped over for no reason. The receiver test revealed the problem.

Good luck

Juerg
Oct 25, 2012, 06:16 PM
Registered User
Quote:
Originally Posted by WantToPlay
Check for a loose rudder cable coming from the receiver. The best way to do that is go to receiver test and wiggle then rudder cable and see if the display says no connection or so. I had the same problem but with ail and the tri flipped over for no reason. The receiver test revealed the problem.
Thanks for the idea. Checked the RX and it's getting a consistent signal and accurately reports yaw inputs from my TX. Cables are secure, servo centres and holds, but won't respond to yaw inputs.

Honestly, the only thing I can see it being is a bug in the software. I just want to know how to resolve it / workaround it.
Oct 25, 2012, 06:46 PM
Registered User
WantToPlay's Avatar
Did you check the board for cold solder points?

Other than that, maybe reloading the firmware could solve the problem.
Oct 25, 2012, 06:47 PM
It's Just a Hobby!
Sudsy's Avatar

Stiff/lazy motor


Hey all. I think my number four motor is causing my problem. As compared to the others it is stiff. I flashed the board with the latest firmware and that was a great improvement. I have a couple of spare motors on the way and may just try taking this one apart and lubing it.

Has anyone had similar issues?

Sudsy
Oct 25, 2012, 07:01 PM
Registered User
cyhyam's Avatar
Quote:
Originally Posted by teccer1234
this is a video of the first flight with my new build tri using the KK2 1.2v I was surprised that it flew reasonable the very first time, I had to trim the RU a lot to get it to fly straight and when I went to disarm it no joy, I had to reset the trim back to takeoff position to disarm, I then reset the servo/RU central now all's ok on that but as you can see in the vid that as soon as I flicked on the AL it flew backwards and I dropped it before it hit me, I thought I'd switched off the AL for the next takeoff but I hadn't and it still flew backwards, managed to turn the AL off and it flew perfectly again, I'm not sure what to do now to get it to stay level when I switch it on AL,
any suggestions?

ray

http://youtu.be/Z5my8HdKYuQ
To remove the need for rudder trim, set "I" to 0 for yaw. Mechanically trim the servo to keep a heading without using the tx trim. Then increase yaw "I" to where you like it for heading hold.

The attitude the model is in when you do sensor calibration is the attitude it will try to be at when you switch on auto level. if you are in a wind the model will move with the wind even if you have a good level calibration.
Oct 25, 2012, 11:47 PM
Registered User
jonesy40001's Avatar
Quote:
Originally Posted by RC911
The numbers listed in the mixer editor tells how much influence your input signals (throttle, aileron/roll, elevator/pitch and rudder/yaw) will have on the selected output channel. Direction can be reversed by making a positive number negative and a negative number positive. I am no expert on this so maybe someone else can explain i better, but I have used the mixer editor a few times to make my T-shaped copters fly properly. Default VTail and Y6 mixer values did not work for me.
Thanks Buddy, I understand what you mean... Maybe I will go and have a play with them and see what happens. I will of course take some photo's of the settings before hand.

Pete.
Oct 26, 2012, 12:31 AM
Registered User
jonesy40001's Avatar
Quote:
Originally Posted by Sudsy
Hey all. I think my number four motor is causing my problem. As compared to the others it is stiff. I flashed the board with the latest firmware and that was a great improvement. I have a couple of spare motors on the way and may just try taking this one apart and lubing it.

Has anyone had similar issues?

Sudsy
I have 3 stiff motors and 1 that takes longer to wind down..... maybe we could do a swap...lol
Oct 26, 2012, 02:50 AM
<Marty>
trying to get my kk2 setup and i think i got it close but one thing i can't figure out is why on the screen it always says the battery voltage is 0.0 ? soon as i plug in the alarm buzzer it goes off! any idea on what i am doing wrong?

thanks all...