Troublesome Tarot 690 - not a happy model

[Zaxxon]

Hi there,
I am having some major and expensive issues with my Tarot 690 that I have just built, I think it may well be the motors.

Specs as follows:

Tarot FY690S frame
Tarot 2814/700kv motors
DJI 30A Opto ESC'S
Naza-m V2 (latest firmware) with GPS
Tarot T-2D brushless gimbal
GoPro Hero3 Black
AR8000x Rx
TM1000 telemetry
ImmersionRC 5.8Ghz 600mw vTx
4S 6200mAh Lipo
Tarot carbon 11x4.7 props

Gain set up:
Basic:
Pitch 150, Roll 150,Yaw 200,

Atti:
[FONT=arial, helvetica, sans-serif]Pitch 80, Roll 80[/FONT]

[FONT=arial, helvetica, sans-serif]I originally test flew the model a couple of weeks ago with the standard motors from my DJI 550 with 10" props and no gimbal / camera and the model was dead stable, very smooth.[/FONT]

[FONT=arial, helvetica, sans-serif]Then the Tarot motors arrived with the new props and gimbal.[/FONT]
[FONT=arial, helvetica, sans-serif]Anyway, the final build went well, everything aligned and ready to go.[/FONT]

[FONT=arial, helvetica, sans-serif]Stupidly I test flew it with the GoPro in place.[/FONT]
[FONT=arial, helvetica, sans-serif]I took off, hovered for a minute and it seemed ok, left and right side slip and all looked pretty good so I added some throttle to gain height and it back flipped and crashed......scratching and ruining the lens of my GoPro 3 black, so one camera down.[/FONT]

[FONT=arial, helvetica, sans-serif]Today I repaired the stripped wires and replaced the landing gear strut that was also broken. I removed the gimbal and balanced the model by moving the battery forward. I rechecked the Naza location settings (all correct).[/FONT]

[FONT=arial, helvetica, sans-serif]Anyway the model is very unstable and it seems like motor 4 is surging, it seems to be unsettled and the constant surging is really upsetting the model. So much so that it was trying to pitch in forward and back. Fortunately only a couple of broken landing skids this time. However I'm not flying this thing until I can figure out the issue. I'll stick to my other dji 550 that has proved to be a great go pro platform so far.
[/FONT]
The Tarot air-frame seems very well made, I was going to purchase a 960 this week, but I'll put it on hold until I can figure this issue out. Has anyone else had the surging motor issue?

 

[wakecrzy2000]

Doesn't seem like it issue with the frame maybe flight controller speed controller. The first crash sounds like a to high of gain issue.

 

[Zaxxon]

The frame is spot on, It's a very nice air-frame.


I didn't think my gains were too bad, does anyone have an example that they are using with a similar set up please?

 

[gtranquilla]

Zaxxon..... When upsizing stock motors to higher power, the motor and prop balancing becomes far more critical.....
The DJI IMU sensors are renowned for being overly sensitive to vibration issues leading to a wide range of flight control problems including flyaways!
Just my opinion based on similar experiences with the F550 and NAZA controllers.

 

[Zaxxon]

Well here is the frame for my next Tarot.

I have added Tarot 333mm tubes & Pro motor mounts give a rotor span of 828mm. i then reused a couple of the old rotor arms and replaced the old landing gear legs (although I may cut these down a bit later, depending on Payload I will be carrying.

Motors are all balanced and I am waiting for a Dubro prop balancer to arrive so I can ensure the props are perfect as my old balancer would not allow a full spin.

 

[jhardway]

On you crash I would go with the esc, It's possible you gains are to low but that all depends on the type of flip, if it was something that happened all of a sudden then I am on the esc/even a bad FC. On the gains for those motors I would say that is a high yaw gain but for the other gains that seems to be a good spot.

In the past I think I possible had a bad FC and it probably got me twice, once i to the manufacturer to switch it out I was good. I am not a big fan of DJI Motors or ESC's

 

[johnthorn]

I have a FY680 with almost the same setup as you, am using Tiger Motors MT2814/10 770kv with12x4 props, 3S lipo and have no problems at all, I would say your gains are way out I use pitch 135, roll 135, and yaw 125, vert 135, ATTI both 100 this gives smooth flight and does not jump around all over the place. I would suggest you check your connections from motor to speed controller are good as sometimes they work a bit loose. I know its a pain to move the speed controllers around but if you have one motor playing up try swapping controllers on it and see if the problem moves around, hen you can isolate the problem
Good luck

 

[TheUFGadget]

Zaxxon..... When upsizing stock motors to higher power, the motor and prop balancing becomes far more critical.....
The DJI IMU sensors are renowned for being overly sensitive to vibration issues leading to a wide range of flight control problems including flyaways!
Just my opinion based on similar experiences with the F550 and NAZA controllers.

I agree tranquilla! This is especially true with carbon fiber frames! I know you have invested teh money already but you might be better off if you invest in the new DJI hex heavy lift propulsion system. That would be the way I would go! Best of luck!