RC India

General Topics => Chatter Zone => Topic started by: v2 eagle on February 04, 2015, 12:02:56 AM

Title: Fixed wing stabilization with KK 2.0 board.
Post by: v2 eagle on February 04, 2015, 12:02:56 AM
Seems like this has been less discussed here in RCI and hence adding my part.
You can use KK board from hobbyking to stabilize fixed wing airplanes and to add auto leveling to them. this is done by flashing the KK board with a firmware called openaero
more info here:
http://www.rcgroups.com/forums/showthread.php?t=1708175 (http://www.rcgroups.com/forums/showthread.php?t=1708175)

a few terms to know:
Uses gyros in the board to maintain the aircraft in the direction you want it to go and removed the disturbances caused by wind.
This does not put your plane back to normal position when you leave the controls.
especially useful for aerobatic pilots who want their planes to be on their rails while doing maneuvers.
lets say when you put your plane in a knife edge and leave it, the board will automatically give rudder input to maintain the level,
But, when you put the plane in a nose dive, it will maintain the axis(Lock) and will hit the ground in a straight path, it will not recover and put your plane and avoid a crash.

Auto leveling:
same as all the aspects of stabilization plus the plane will recover from bank and pitch and will level itself when the control inputs are removed.
ie, when you take your hands off the sticks, it will come to normal level, much like dihedral but in a better way.
this takes the use of inbuilt accelerometer and measure the change in bank and pitch and will correct it when the inputs are removed.
this also limits the bank and pitch of the plane to certain degree set by user(30 degree by default)

>This does not have any auto-landing function or any crash avoidance system, it simply levels the plane like a dihedral.
>All the autoleveling and stabilization depends on a perfect air frame, a sloppy servo link can spoil the performance and this doesnt mean that the openaero can still save this.
>This can be used on both flying wings and conventional air frames.
>Setting the horizon AKA calibration plays a vital role in auto leveling. if you calibrate wrongly, it will maintain that level and you will feel like the plane is banking on one side even with leveling.
>default values given in the PID tuning is good for skysurfer and bixler airframes and should be good for other planes too in the same wingspan however should be tuned for best performance.

Now lets get down on how to do it:
you need ,
4 channel electric airplane(not sure of their performance in nitros and 3 channel rudder only gliders)
KK board( v 5.5, KK 2.0 LCD board, KK 2.1 LCD board whatever)

follow the instruction given in rcg link given and download the lazyzero software from here http://lazyzero.de/kkflashtool. (http://lazyzero.de/kkflashtool.)
once installed you will have a window that has options to select the type of board and firmware and usbasp type.

more info on this video here:
https://www.youtube.com/watch?v=3KFCbe_FRwE (https://www.youtube.com/watch?v=3KFCbe_FRwE)
(though there are countless videos available online, this is one good resource to count on!!)

Enjoy and ask any questions if you have any.



Title: Re: Fixed wing stabilization with KK 2.0 board.
Post by: v2 eagle on February 04, 2015, 12:19:32 AM
Few updates on the latest firmware:
it is more customizable and you can make any pin to control any servos.
seems like there is some bug with throttle values and it doesnt stops the motor once started, hence connected the esc directly to the RX.
the rest of my connections in the output are,

OUT 1:Aileron(should use y connector for multiple servos)
OUT 2:Elevator
OUT 3:Rudder

Input 1:Aileron
Input 2:Elevator
Input 3:No connection
Input 4:Rudder
Input 5:3 position switch

The three position switch is used for setting the flight profiles. you can skip either profile 2 or 3 if you only have a 2 position switch in your TX, but profile 1 is mandatory!! skipping the profile depends on the airframe

Flight profile 1:
no stablization
no auto levelling
this is mandatory and saves your plane if the board goes crazy, you can switch to this mode and fly your plane manually.

Flight profile 2:
only stablization
no autolevelling
you can skip this profile if you are into FPV or using a glider like airframe.

Flight profile 3:
stabilization and auto leveling included
you can skip this profile if you are into 3D or acro flying.

Title: Re: Fixed wing stabilization with KK 2.0 board.
Post by: v2 eagle on February 04, 2015, 12:34:07 AM
Profile selection:
for each and every profile option, there will be a trigger value like -1240, 0, 1240 for profiles 1,2,3 respectively.
you might need to change the values to match the TX.
to do this, simple go to the receiver input menu and see what values are for each position of the switch.

in my tgy9x the 3 position switch has 0,1,2 positions.
for 0 the value would be -1240(closely, yours might differ)
and for position 1 would be 0,
and for position 2 would be 1240

note down the values and set the same in the profile trigger value. when done come back to status screen and flip the switch and see if the profile change is shown in the screen( though the profile changes instantly, it will take a second to show it in the screen as the screen is polled at certain intervals. so flip the switch and wait.!!)