ArduCopter-3.2.1 Beta Testing

ArduCopter 3.2.1-rc2 (release candidate #2) has completed beta testing and has been released as the official version available through the mission planner and other ground stations.

Changes from AC3.2 are listed below and in the ReleaseNotes:
1) Enhancements:
    a) reduced twitch when passing Spline waypoints
    b) Faster disarm after landing in Auto, Land, RTL
    c) Pixhawk LED turns green before arming only after GPS HDOP falls below 2.3 (only in flight modes requiring GPS)
2) Safety Features:
    a) Add desired descent rate check to reduce chance of false-positive on landing check
    b) improved MPU6k health monitoring and re-configuration in case of in-flight failure
    c) Rally point distance check reduced to 300m (reduces chance of RTL to far away forgotten Rally point)
    d) auto-disarm if vehicle is landed for 15seconds even in Auto, Guided, RTL, Circle
    e) fence breach while vehicle is landed causes vehicle to disarm (previously did RTL)
3) Bug Fixes:
    a) Check flight mode even when arming from GCS (previously it was possible to arm in RTL mode if arming was initiated from GCS)
    b) Send vehicle target destination in RTL, Guided (allows GCS to show where vehicle is flying to in these modes)
    c) PosHold wind compensation fix
    d) prevent infinite loop with do-jump commands pointing at each other
    e) pixhawk memory corruption fix when connecting via USB
    f) vehicle stops at fence's alt limit in Loiter, AltHold, PosHold (as it did in AC3.1.5)
    g) protect against multiple arming messages from GCS causing gyro calibratoin failure

Thanks to Raph for the video.  This is actually a video from AC3.2 until we have one specific to AC3.2.1.

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    • Developer

      Well, that's not good.  AC3.3-dev has not gone through beta testing yet so no guarantees it will work well.

      • I attempted to autotune today.

        The left-right part (the first half) was normal. During the forward-backward (second half) phase and in particular during the forward movement, I noticed that right after each oscillation the copter was adding a substantial amount of yaw towards the right. Wind wasn't strong enough to be a factor and was changing direction quite rapidly.

        Is it supposed to do so? I've never seen it when I've done autotune in the past, but I've changed motors and propellers since (to very well balanced KDE motors and 15 inch props). It flies fine otherwise. Autotune terminated and I saved the new PIDs, which are ok (not perfect but definitely better than the defaults).

        Log attached

    • most likely they got it from the dev repo 

  • Developer

    I've been a bit absent for the last 2 weeks because Tridge and I were in SanFran attending the Embedded Linux Conference and meeting with 3DR people in the Berkley office.Back in Japan now and we've apparently resolved the altitude issue that were holding up AC3.3-rc1 so hopefully AC3.3-rc1 will be out by this weekend (I've said that before but this time it should really happen).

    • Hi Randy,

      Is AC3.3-rc1 only for Pixhawk? Regards.

      • Developer


        Yes, only for Pixhawk and other fast CPU boards (Flymaple, PX4-v1, VRBrain, Linux, etc).

        • That's kinda cruel. I just bought APM 2.6 original hardware and now it's that I'm stuck with drifting height problem and incomplete EKF filter (which is in fact not working properly in this firmware, but it takes valuable ROM size, because lack of which development on APM stopped).

          Maybe you can at least fix altitude things and make 3.2.2?

          What should I do now? Send my APM to store and ask for moneyback because hardware is unusable for me? Man, that just destroys all positive image APM boards. :(

          • Developer


            I think Rob Lefebvre can help look into the specific issues some users are having with AC3.2.1 on the thread opened for that issue.  We went through months and months of testing including many APM2 users but if it turns out to be a firmware issue that can be fixed we can release a 3.2.2.

            I've also sent a note to the 3DR guys responsible for the store and asked them to add a note that recommends people purchase the Pixhawk instead of the APM2.6.

            • Great Randy :) I have the Pixhawk in my wishlist but, for the moment I'm part of the nostalgic APM users and if something can do to get more stable Pos hold it's great,  but I'm not worry because I learned a lot trying to have my copter more stable and now is another guy, but anything to be better is welcome and can help to test.

              I agree with Marko that 3DR have to alert buyers sometime ago that APM is not possible to update anymore.

              Anything I'm not shure with Pixhawk; I'm waiting yet for an external compass to solve compass interferences, If Pix have one internal compass that's means problems again? I read many post with Pix with compass interferences, any solution?  thank's

              • Hi Cala
                The Pixhawk internal compass works fine (my X8 uses it alone) provided:-
                a) The case screws are not magnetised
                b) It is far enough away from any other source of interference

                If this is not possible and/or for backup then an external compass is required.
This reply was deleted.


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