AC3.3 TradHeli Release Discussion

WARNING to TradHeli users:

Do not attempt to fly AC3.3 until you hear otherwise from me.  I have not even bench tested it yet, let alone test flown it.  There are quite a lot of changes that have gone in that could be crash-o-matic for helicopters.

AC3.3 release for Tradheli is likely to be delayed.

This post will serve as the official release progress thread for TradHeli.

Warning: DO NOT FLY RC6!  It has a critical bug that will likely end in a crash.

Warning for RC5:

RATE_YAW_FILT_HZ param will change defaults from 5Hz to 20Hz to be more suitable for helicopters.  If you have never changed this parameter from 5 before, then it will automatically update the value to 20 without warning.  This much faster filter will probably require reduction in your P and D terms, and the yaw may oscillate badly.  Be prepared to retune these.  As a safety measure, probably cut them in half for your first take-off.

Warning #2 for RC5:

I accidentally broke the Landing Detector.  It will probably never trigger.  You should land in Stabilize mode, or be prepared to shut down the motor as soon as it touches the ground in Alt_Hold, Loiter, Auto, etc.

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    • Currently, my advice is to stick with 3.2 until 3.3 goes stable for any high cost or commercial systems.  I would appreciate anybody doing this as a hobby and/or on lower cost or test machines to start testing the 3.3 RC's now.  It is quite stable, just not quite finished yet.

  • i wanted to see if anyone can help with determining what is going on. I am getting bad collective pulsing in alt hold and loiter. Attached is a log from the test flight. I never saw this behavior before. I am thinking that it might be mechanical. So I plan on resetting the swash and the blade pitch limits to rule this out.  I am running 3.2.1 to get it dialed in first prior to upgrading the firmware. This Helicopter fly great for over 15 flight hrs prior to this issue. 

    Thanks for the help.

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    • Yes this is most likely a pretty simple fix. You need to tune your alt hold gains, vel_z_p and accel_z_*. If you get crazy pulsing they are probably too high.
      • Great. Thanks.

        I just re zeroed the swash and reset my blade pitches. The next will be adjusting vel_z_p and accel_z_



  • Just tested RC10 for an intitial setup, however, in stabilize mode we hae full control of the swash, but, as soon as we arm the motor we don't have any control over the swash or tail other than collective. Is this the correct behavior? It seems dangerous that we can't give inputs in stabilize mode.

    This is my first setup for a arducopter heli so not sure if this is the expected behavior or a bug.

    • To be honest you should get your heli running g on AC3.2.1 before attempting to run a beta version because you can virtually eliminate the possibility of it being a bug.
      • That is true, but, there are a ton of changes for 3.3 so I would prefer to just start there. I am quite familiar with Ardupilot and very familar with setting up heli's in general, just new to the Arducopter Traditional Heli and wondering if this observed behavior is normal.

        The collective works, but, roll and pitch do not. 

        • Jason, yes that is how it is working now. As soon you startup the motor you have full control I can a sure you. I fly a 500 size Heli with this version.

          Flown 3 battery packs with 3.3 RC10. Have done only following modes: Stabilize, Alt Hold, Loiter RTL.

          If your collective stick is right down after the motor start up the FC will not auto disarm anymore. You have to manually disarm. If you auto land ( RTL) it will disarm by itself. If you get used to it it is fine with me. No unintentional disarm wile throttle is down. That.s ok.

          But before the first motor startup it will disarm with low throttle.

    • The tail won't become active until you have the main motor signal high. But the swash should always be active AFAIK
      • No, he's right.  In RC10, the swash stop moving during the intermediary stage between arming, and the point where the rotor speed passes H_RSC_CRITICAL.  You shouldn't be able to take off like this so it's safe-ish.  But it's not right.  It was due to a downstream change that Randy made without realizing how it would affect helicopters.  It will be fixed as it's not right.

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