SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Oct 25, 2012, 02:19 PM
Registered User
gjalbert's Avatar
Tualatin, OR
Joined Oct 2009
273 Posts
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
gjalbert is offline Find More Posts by gjalbert
Reply With Quote
Sign up now
to remove ads between posts
Old Oct 25, 2012, 02:54 PM
It's Just a Hobby!
Sudsy's Avatar
Joined May 2012
841 Posts
Got Parts

Oh Boy!!!
Sudsy is offline Find More Posts by Sudsy
Reply With Quote
Old Oct 25, 2012, 04:13 PM
It's Just a Hobby!
Sudsy's Avatar
Joined May 2012
841 Posts
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
Sudsy is offline Find More Posts by Sudsy
Last edited by Sudsy; Oct 25, 2012 at 05:21 PM.
Reply With Quote
Old Oct 25, 2012, 04:15 PM
safer on the ground
teccer1234's Avatar
wilts, United Kingdom
Joined Jul 2006
719 Posts
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)
teccer1234 is offline Find More Posts by teccer1234
Reply With Quote
Old Oct 25, 2012, 04:54 PM
Registered User
Canada, ON, Windsor
Joined Mar 2012
614 Posts
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.
Invid is offline Find More Posts by Invid
Reply With Quote
Old Oct 25, 2012, 05:29 PM
Registered User
Del-Dredd's Avatar
Near Aberystwyth - Wales
Joined Aug 2004
2,116 Posts
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.
Del-Dredd is offline Find More Posts by Del-Dredd
Reply With Quote
Old Oct 25, 2012, 05:34 PM
Registered User
Canada, ON, Windsor
Joined Mar 2012
614 Posts
Quote:
Originally Posted by Del-Dredd View Post
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.
Invid is offline Find More Posts by Invid
Reply With Quote
Old Oct 25, 2012, 05:42 PM
Registered User
WantToPlay's Avatar
United States, KY, Springfield
Joined May 2012
7 Posts
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
WantToPlay is offline Find More Posts by WantToPlay
Reply With Quote
Old Oct 25, 2012, 06:16 PM
Registered User
Canada, ON, Windsor
Joined Mar 2012
614 Posts
Quote:
Originally Posted by WantToPlay View Post
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.
Invid is offline Find More Posts by Invid
Reply With Quote
Old Oct 25, 2012, 06:46 PM
Registered User
WantToPlay's Avatar
United States, KY, Springfield
Joined May 2012
7 Posts
Did you check the board for cold solder points?

Other than that, maybe reloading the firmware could solve the problem.
WantToPlay is offline Find More Posts by WantToPlay
Reply With Quote
Old Oct 25, 2012, 06:47 PM
It's Just a Hobby!
Sudsy's Avatar
Joined May 2012
841 Posts
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
Sudsy is offline Find More Posts by Sudsy
Reply With Quote
Old Oct 25, 2012, 07:01 PM
Registered User
cyhyam's Avatar
Highland, CA, USA
Joined Jan 2001
1,112 Posts
Quote:
Originally Posted by teccer1234 View Post
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.
cyhyam is offline Find More Posts by cyhyam
Reply With Quote
Old Oct 25, 2012, 11:47 PM
Registered User
jonesy40001's Avatar
Australia, QLD, Meadowbrook
Joined Sep 2012
180 Posts
Quote:
Originally Posted by RC911 View Post
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.
jonesy40001 is offline Find More Posts by jonesy40001
Reply With Quote
Old Oct 26, 2012, 12:31 AM
Registered User
jonesy40001's Avatar
Australia, QLD, Meadowbrook
Joined Sep 2012
180 Posts
Quote:
Originally Posted by Sudsy View Post
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
jonesy40001 is offline Find More Posts by jonesy40001
Reply With Quote
Old Oct 26, 2012, 02:50 AM
<Marty>
United States, KY, Springfield
Joined Jul 2011
1,870 Posts
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...
magic_marty is offline Find More Posts by magic_marty
Reply With Quote