ArduCopter-3.2 beta testing

Warning #1: PX4/Pixhawk users upgrading from AC3.1.5 (or earlier) may need to re-do their compass and accelerometer calibration because AC3.2 also uses the backup compass and accels.  Pre-arm checks have been added to ensure this has been done.

Warning #2: on the APM2.x the logs must be downloaded using MAVlink instead of the terminal.

AC3.2-rc14 is now available for BetaTesters through the mission planner’s Beta Firmwares link.  The full release notes can be found in ReleaseNotes.txt and changes from -rc13 can be seen below.

     Feel free to raise issues found during testing on this discussion or in the new support section in the APM Forum.

     It’s a big release with “the onion” restructure and a bunch of new features (including these 57 closed items) so we need to re-test almost everything including all flight modes, all mission commands and all the new features.  Marco and I will be maintaining (and adding to) this testing list.  Issues reported will first be checked by Jonathan, Marco and I and then confirmed bugs/issues will be put on the github issues list (and then hopefully fixed).

     Thanks especially to the beta testers who put their copters at risk testing each release.  Enjoy!

Changes from 3.2-rc13
1) Safety Features:
     a) fail to arm if second gyro calibration fails (can be disabled with ARMING_CHECK)
2) Bug fixes:
    a) DCM-check to require one continuous second of bad heading before triggering LAND
    b) I2C bug that could lead to Pixhawk freezing up if I2C bus is noisy
    c) reset DCM and EKF gyro bias estimates after gyro calibration (DCM heading could drift after takeoff due to sudden change in gyro values)
    d) use primary GPS for LED status (instead of always using first GPS)

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  • Hi Randy,

    don't know if you see my previous post about this case, basically i'm using rc12 which is working pretty good so far as except the flips in Acro. Would be cool if ve can solve it.

    Attached the new log and below my ori answer :

    Randy, attached you'll find the new log from today.

    As expected fast and slow rolls in Acro mode are working like charme.

    The first flip was nearby ok, was this luck ?
    Second flip and *bam*, there it lies.

    Same scenario as last time but slightly different :
    1 Flip -> copter lose control and motors are spinning slowly, pilot inputs are ignored.
    2 Switching back to Stabilize
    3 during fall to ground, the copter seems reaching the right attitude,was it luck ?
    4 what happens next the motors were fully spin up just quick.
    5 then *bam* there it lies.

    This time "only" 5  props decided in collective to leave the copter
  • Hi all,

    I recently updated my firmware to 3.2rc12. I got a pre-arm check message saying that gyro calibration failed and that i was having a bad gyro health. I trying to fly off from a big yacht that was rocking mildly. With the rc11, i managed to take off without any issues. Perhaps the pre-arm check is too strict? I had to disable pre-arm check in order to fly.

    Is there a value that i can change? If not, how do I disable gyro pre-arm check only?

    Attached is my logs if you want to take a look.

    Thank you in advance and really appreciate the development team of 3.2.


    • Developer


      Instead of disabling the pre-arm checks completely, it's probably better just to "Skip INS".  That will leave all the other checks in place.  There's a to-do item to support taking off from boats to AC3.3.

      The check of the gyros was added after a crash in -rc11 caused by (we think) the gyro calibration failing, the user being unaware and taking off but then having attitude problems (heading and pitch were off).

      When the gyro calibration fails it goes with it's best guess of the offsets and sometimes it's fine but sometimes it's not.

      I think there's two things we could do:

      1. the ground station can be setup to allow the user to easily re-do the gyro calibration.  This would avoid the plugging/unplugging of the whole system.

      2. we could suppress the "bad gyro" health message that gets stuck on the HUD in case that's annoying.  The warning is already there in the pre-arm checks so it's probably not necessary.

      What do you think?

      • Hi Randy, 

        Okay. I will definately just "Skip INS" on the pre-arm.

        You are right. After upgrading to the pixhawk, I have noticed that there is a lean to the left or right because the gyro was not able to calibrate properly. I anticipated it when I arm the copter and the HUD begin to move to the left or right without the copter even taking off. So what I will do is to unplug and plug again when the rocking settles down abit.

        But now, ever since i enabled EKF, the lean is not as drastic as before and haven't notice the HUD to drift before taking off. Is the EKF helping the situation?

        1) So yes, i think it is a great idea to re-do gyro calibration from the ground station. I'm sure it will also benefit us on land as well. But if we re-do the calibration, will it still fail? I plug and unplug several times but kept failing every time because the boat was always rocking even when it settles down abit.

        2) For me I don't find all these messages annoying. I would like to know them actually so I can fly more cautiously. But I am not sure if they are too strict. 

        Don't get me wrong, I am not complaining. It wasn't meant to be flown off a boat anyways. ;p

        I will definitely follow your to-do list to support taking off from boats. There are also several ideas that I will like to share because I do frequently fly at open sea. I'll leave it for another discussion.

        Thanks Randy ! 


        • Developer


          Thanks for the feedback.

          It's becoming pretty clear to me and a few others on the dev team that the EKF is far superior to DCM in many ways.  I'm not surprised to hear you think it may be better dealing with the gyro-calibration failure.  It seems better at dealing with almost all other failures so it makes sense.  We're not recommending everyone just moves over to the EKF just yet because it hasn't "run the gauntlet" of a huge number of users so there are still likely some corners where bad things will happen.

          One suggestion from Leonard regarding this problem of taking off from boats is we just make the gyro calibration really long.  Right now it works by attempting about 10 really short calibrations but instead we could perhaps try one really long calibration period.  As long as the boat is rocking back and forth and not changing it's heading too quickly etc it would probably work.

          • Randy,

            Thank you for the information. Will follow your development closely. 


    • I am Still crossing my fingers something is worked out for boaters. It can be a major issue trying to arm and fly while in a moving boat.

      • I would also like to see an RTA (return to assigned) mode so a beachfront failsafe location can be selected without having to arm there. We also desperately need more than 8 channels as the mode and functions increase in number.  

        • Developer


               I think you could use Rally points for that.  It's only available on Pixhawk I believe.

          • Thank you, Randy, I missed that. They should work perfectly. 

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