I am new at the tricpoter scene and I have problems flying my RCExplorer design

[nadaslaci666]

Hi Guys and Girls

I've recently built one tricopter folowing almost every suggestion that David said on his video "Tricopter Build". I did some changes due to some financial concerns and Hobbyking's stock.
I am using KK2.1 (totaly original), DT750 motors, 11X4.7 props (all the same direction), Turnigy AE-25A ESC (totaly original), and a diferent servo because the suggested one broke it's one plastic gear on the second run. Now I am using a standard servo, not so fancy but works so far, the tricopter does not spin.

But


When I "try" to fly it I can't really. When I give it throttle input it shoots up and If I decrease the throttle or pull it down completly, it just keeps on climbing, or staying on altitude until one of the motors stops, then it falls, and If I am lucky and I am distant enough from the ground, I can give it some power to manage it, but it really not a solution. I am new to this part of the hobby, I do not want to do tricks or wizz around with my tricopter, I only want to hover and gently fly around on a field, when it is not windy. Maybe I want to put some FPV gear on it, but until I can't get away whitout breaking an arm or a prop, I won't risk my equipment.

I am new to the KK2.1 board, and I think I have problems with it's settings, so If you cold help me out with some suggestions about what values should I change I would be pleased.

I know that I sould have refreshed my ESC-s or buy different ones, and maybe refresh the KK board also but I do not have the equipment or the money to do so. And how I said I do not want to do crazy things with it so I am not offended if it is not a speed daemon or a trick machine.

Thank you for your help

My values in the KK 2.1

-PI Editor
Roll: PGain:115, PLimit:100, IGain:25, ILimit:20
Pitch: PG:115, PL:100, IG:25, IL:25
Yaw: PG: 45, PI:20, IG: 50, IL:10

-Mode
Self Level : Aux
Link Roll pitch: Yes
AUTO Disarm: Yes
CPPM Enabled: No

-Stick Scaling
Roll:30
Pitch:30
Yaw:30
Throttle:15 but I does crazy stuff on 4 also

Misc. Settings
Min. Throttle 20 (I have a Turnigy 9X)
Height Dampening: 0
Height Limit: 30
Servo Filter: 80

Chanel: 1 2 3 4
Throttle: 100 100 100 0
Aileron: -87 87 0 0
Elevator 50 50 -100 -100
Rudder: 0 -1 0 54

IF you need any more information please tell me I will upload it .

 

[xuzme720]

I think it might be the KK2.1 firmware. I can't remember now if it was Pgerts or Tritium but one of them said the stock firmware was rubbish and had to be updated before flight was possible.

 

[Cyberdactyl]

Hi nadaslaci,

Welcome.

I have pretty much an exact replica of David's tricopter.



While you may have any number of physical issues (you only provided little else other than the board's settings), I think you have your P and I setting way too high. My tri flies very well and I use;

P Gain 85
P Limit 35
I Gain 25
I Limit 20

Now, I'm not suggesting you use my settings, merely to suggest yours may be much too high for a tri the size as 'ours'.

Your servo filter setting looks ok, as well as everything else. You didn't list your auto-level settings. Mine are;

P Gain 75-ish (depending on how tight of an area I'm in)
I Limit 35-ish

 

[xuzme720]

Would P gain cause motors to stop like nadaslaci666 describes? I agree they are much higher than I'd expect, but based on KK2 experience, I wouldn't think it would be that drastic. I haven't done anything with the KK2.1 so maybe it's something new with the board?

 

[Cyberdactyl]

Would P gain cause motors to stop like nadaslaci666 describes?

No. And that 'motors stopping mid-flight' is appearing quite often in this forum I notice.

 

[nadaslaci666]

The engine stops are happening after I pull back the throttle but not in the same time, I mean I pull it back right after it shoots up and it does not starts to lose altitude and in a moment maybe 10 second later one of the motors stop. it feels like I could only gain altitude but not loosing it while I give any throttle. I have two things that can be wrong, ( I will try your settings Cyberdactyl and thank you) but I think the problem is at the hight dampening or mybe at the stick scaling throttle which is only 5 but when I pumped it up it only shoot up faster or did not at all. Or maybe I sould change the Min throttle. I mean I do not know why it does not rise up slower or why I cannot slow the props down to a level when they are still spining but slower and I could come down with a manegable manner.

Thank you for your suggestions
You are awsome

 

[DDSFlyer]

Simple question...did you calibrate the ESC's?

 

[nadaslaci666]

If you mean puting them to a same programing values or switching off the Lipo cut off and going throught the calibration on the KK board?

Then my answer is yes.

I think I found the problem I've been expirementing with the Tricopter (tie it down so it could raise just a few centimeters from the ground) I found that When I put everything to a neutral position in the transmitter calibration. I used the normal trims not the subtrims.

After that I could pump up the stick scaling on the throttle up to 60 and everything was manegable (before only at 30, it shoot up and did crazy things" I mean It only lifted up a bit and I could slow the props or speed them up on command.

I cannot try it right now because it is dark outside but I hope in the morning everything will be fine. And I also dialed down my PI gain and limit as suggested.