Few month ago, I decided to build long flight time UAV. After quick google search, I came to http://vimeo.com/84302289 . Result is awesome in my case. I ordered everything for this setup.
Motors: Tiger U8 100KV
Propeller: Tiger 28x9,2
ESC: Hobbywing Platinum 30A
Battery 6S4P GEB8043125
Now, I come up to next problem, which is PID tuning of this large craft. People who made these kind of setups are flying with DJI Naza flight controller. I prefer PixHawk with ArduCopter on board :)) .
Did some one do these setup?
What kind of PID values did you have ? Or is there any way to calculate such values? I need some close values to fly on Stabilize mode to figure out auto tune.
As you know it's dangerous to fly with wrong PIDs on such huge and expensive quadcopter, where each props cost 160$...
not yet.. I'm on the way of building of my copter..
How about now?
Hi Yerzhan, I am also building a large H8 with the U11 motors running 28" props. I have tried many times to fly an H with the Dji A2 but NEVER worked as there mixing for the arm only works for increasing motor power and NOT when decreasing power thick causes serious instability.
Thankfully Arducopter 3.x works flawlessly. as for PID, not got that far on the U11 H but I would point out the motors will rev slowly and suspect the P will be high.
The last H8 was on 18" props and like the rest of them I have used the default PID, ran Autotune and dropped them down about 15% each time and this appears to work well for all sizes of rig for me.
Pixhawk and APM both are just fine with U8 motors. I've made/flown quadcopters with U8 170kv and they fly very well and smooth.
I can share params this weekend.
just send me an email if you need.
wow, quite long flight.
Pixhawk should work fine, Not that I don't trust Autotune, but I just manually tune, then fly, then manually tune accordingly, and repeat many times. Autotune I imagine to be a bit... well scary when you see so much cash flipping around in the air. I've built a few Mega Rigs...
Any flight controller should fly it fine given you have access to PID parameters.
I am currently working on a novel autotuner which is open source (github/MChehadeh/PIquad). The full beta release is expected in the beginning of 2017.
For now, just make sure that (Sequential steps):
* the flight controller is isolated from vibrations.
* Tune with PD values and set I=0 as you start for pitch/roll/height.
* Calibrate acc and gyro as accurate as possible.
* No controller should act on X, Y channels.
* D value should be always about two times the P value (before auto-tuning).
* Start with small P values, test at low altitudes, increment P values, re-fly (keep P-D relation fixed).
Hope this helps!
Try an autotune one axis at a time and see how you go.