as you can see it is a standard Trex 450 with hs-65mg on the head and a fast turnigy mid size for the tail.
Having a bit of experience with RC helicopter I would say that all the basic is done:
blade balancing
swashplate setup
arduipilot built-in governon using ESC’s RPM output
“correct” pitch for cyclic and collective
all the basic FC setup.
Now I have done few flights, I have archived a good flight time using low head-speed and 3s liion batteries (30min if I don’t remember wrong), but I’m strugling a bit with the tuning. In particular I can’t complete remove oscillation and overshot on roll, pitch and yaw.
Attached and linked you can find my current setup plus couple of log files for you help me providing feedback
Plus I don’t understand why the Fport is not sending telemetry to my radio. The FC correctly receive channels values from the uninverted Fport but it can’t send telemetry back. Same setup(RX, radio, script) is used on other drones without issues. Any suggestions? Heli parameters.param (19.9 KB)
First, set H_OPTIONS to 0.
Set ATC_RAT_YAW_I to 0.22, ATC_RAT_YAW_FF to 0 ATC_ACCEL_Y_MAX to 65000
Reduce ATC_ANG_PIT_P and ATC_ANG_RLL_P to 3.8.
Double check AHRS shows perfectly level in MP when rotor shaft is vertical.
Double check your swashplate level using SV_MAN set to 1
The RX is FRSKy r-XSR with Fport firmware and I modded it to have un-inverted Fport. Same solution (hw and sw) is used on another FC without problem.
The RX is connected to T2 pin on the speedeby f405. I know not the latest H7 but technically capable of Fport isn’t it?
On the main topic. I updated the parameters as suggested. I also noticed/remembered that last time i used the heli I made some HW changes and the FC was not sitting anymore like before so I have applied your suggestions and adjusted the FC trim to be “flat” again.
The addition log you can find here is with the latest settings.
I would say it start to be much better but still something to tune on the roll axis in particular. Can you see this from the log ?
Just as note, I received in my radio the radiolink rssi so the Rx is definitely sending something back. I don’t get how is possible that fport is decoded but the FC is not sending telemetry stream
Hi Lorenzo,
sorry for the slow response.
I would advise to further reduce ATC_ANG_PIT_P and ATC_ANG_RLL_P, perhaps to 3.5.
Also try set ATC_RAT_PIT_FF to 0.12, ATC_RAT_RLL_FF to 0.13 and ATC_RAT_RLL_I to 0.13.
Good job on re-leveling the setup.
Once you get to a sufficiently stable hover without visible oscillations I recommend fine tuning your attitude and rate controllers with either the analytic tool or the transmitter based tuning.
today i spent an entire battery tuning a bit better pitch and roll. I am still far from personal standard but at least in a good direction. In the same folder I added a “summary” flight post tuning
@Lorenzo_Pessah maybe you are better at manual tuning. In some ways I feel it takes longer, especially if you are seeing behaviors that you can’t tune out. Then you just start guessing.
Autotune can help as it can tune the gains to there best potential but again you may still some behaviors that it can’t tune out but at least you have data to see what is going on.
There is also analytic tune which requires you to tune it on your computer. But you can see what limits your tune. Certainly it has its limitations but it reduces the guess work.
The wiki shows how to perform autotune and there is a post on how to use analytic tune.
I have now updated the FC to a similar matek h743 made by Triumph autonomous system.
Funny enough fport telemetry is still not working despite having move to inverted F port, having re-binded the Rx making sure I was selecting telemetry and double-checking all parameters.
I tried to change receiver, update firmware, change Fc port from TX6 (serial7) to RX6, checked radio program with companion. Still can’t get telemetry. Fired up another drone with Same FC and I got telemetry straight away.
So finally today, after more tuning I manage to have some full stable flights in all flights mode.
I had to massively reduce ATC_ANG_PIT_P from original 4.5 to 2.5, ATC_RAT_PIT_P to 0.025 and even tune velocity gains increasing D from 0 to 0.6
I would like to thank @Ferrosan for his offline support.
I have deleted most of the logs in the shared folder to save space but happy to re-share them if needed. I uploaded there the today log and attached here new file parameters
but the F.port mystery is still there. maybe @tridge or @rmackay9 can check if there is any bug in the trad heli firmware because I lost hope and test to do to understand.
I’ve added the F.Port telemetry issue to the 4.6 issues list.
So you mentioned that it is working on another flight controller. It’s an identical flight controller? E.g a Matek H743? .. and they’re running the exact same version of AP?
If it works on one FC but not another the issue could be:
configuration issue (e.g parameters)
hardware failure
It should be possible to narrow down what the difference is through a “binary search”. E.g. repeatedly dividing the problem in half and re-testing.
Happy to help look at parameter files or dataflash logs from the two FCs if you have them
