Need help tunning direct drive fixed pitch electric tail on traditional heli 4.0.7

Hi, i m trying to run arducopter on a traditional heli haven’t got much luck so far i m running 450 size heli with flybar system on it and electric ddfp tail on it , i can find lots of tunning guide for servo tail normal tail but cant find enough info on ddfp systems so i really need someone to help me on this cause its been few months i m trying to get this thing to fly can someone help me tune ddfp tail tris how to tune and idle speed etc , right bow i cant upload parameters or logs right now cause i m not on my house but will get there tomorrow will definitely uploads parameters file , how i start both main rotor and tail at the same time so it doesn’t rotate the heli at the spot before even hovering and what trim position to use for tail 1500pwm more or less?

I know I am repeating myself here, but why not update to ArduCopter 4.1.5???

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The reason i m not using latest stable version is because then it doesn’t work with q control ground station app on Android the app doesn’t know what frame it is and doesn’t show any parameters if i go on vehicle setup its blank , i also tried old versions 4.1.2,4.1 also but got the same result and mission planner on Android is very unresponsive and laggy and hard to use

Our vehicles work fine with “QGroundControl daily”. So update QGroundControl and all work fine again.
It is a well known fact that all ground station stable releases are terribly outdated (both MP and QGC) and that only the beta/daily versions work properly.

The vehicle FW needs to be the latest stable because it is critical to the safe operation of the vehicle. The GCS on the other hand is not as critical, even if it crashes, the vehicle will continue to operate.

I hope you now understand which firmware and software to use for a safe operation of your vehicles.

Ok , today i tried hovering now i face new issue the issue is that the tail will blow up for half a second and the heli will climb suddenly on its own, and on ground station i see ekf imu o forced reset , is this because of too much vibration i m getting on the board its weird the tail will try to hold but suddenly it will go jerk and come back same with the head servos

Please provide a .bin log file.

Cani upload it here on this site or i have to use g drive

you need to use something like and provide a link here. i put all tbe files bin and .log u can extract and see the logs

That link is access restricted. Why didn’t you did like I told you to?

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Ok this is the link now

Here is the link for the log files i upload in zip

Is this an electric powered heli? For electric heli’s, the H_RSC_IDLE param should be 0. I see you have the rotor speed controller set up for throttle curve but your throttle curve points are all 70%. If this is an electric powered heli, they will still be pretty flat but I dont think it would be all 70%. What is your min and max collective blade pitch in degrees that corresponds to H_COL_MIN and H_COL_MAX?

TBH, I don’t have any heli’s with DDFP tails nor have I helped anyone set one of these up. I would think that you need to set the ATC_ACCEL_Y_MAX param higher than 18000. I would recommend at least 40000. Set your LOG_BITMASK to record PID messages. Then we can at least see what term is might be over tuned.

I would recommend tuning the ATC_RAT_YAW_P and ATC_RAT_YAW_D terms using the tuning feature with a knob on your transmitter. That way you can change the value with the knob.

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I tried tunning atc rate p and atc angle p but very less effect and also i discovered new problem if i ty hard to lift heli the tail esc will stop randomly before even hovering and reboot again is that too much vibration causing that

My minimum collective is 1400 and max is 1650 pwm i have not set this heli to fly on negative pitch i only want this to fly normal flight i have set the idle helis rsc on 25 % when i arm it will idle at 25 and when release motor interlock the tail will start and it will go to 70 percent desired speed but tha tail jerk very aggressively and then the tsil esc will stop completly the heli will rotate and esc reboots

I was able to see your PWM for those settings. I want to know what is the actual blade pitch in degrees that those settings relate to. You’ll need to program about -2 deg of negative blade pitch in order to descend when flying in forward flight.

Interesting. So I would expect it to spin the tail rotor but not jerk it. you are certain the ESC is rebooting? Do you have the log from when the tail rebooted? I can’t imagine that vibration would cause an ESC to reboot. Maybe a power fluctuation.

I have a video if u want i can upload

In terms of blade angle degree i actually dont know and i dont have any tools to measure it

And i have the latest log in whivh i mounted the autopilot on vibration free rubber damping mount i dont know if it reduced the vibration can u check it for me

These are here new log files and with latest stable firmware 4.1.5 WeTransfer - Send Large Files & Share Photos Online - Up to 2GB Free