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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                • The cord is 11 inches long. Okay about the connector ... I've had issues with that myself. I specifically found an ad for one for the pixhawk then they ship it with the 5 pos one for the apm.. grrrrr!  BUT... hold the phone they ship the little plastic 6pos end as well. So after putting on my readers and being really careful with a pin I was able to switch it to the 6pos one in only a couple minutes. So your covered either way. Yes it has a compass too. That's the 4 pos cable that goes to the I2C port just like the 3dr one does. Its really nice the way they are ALL encased in that nice solid one pc rubber. I then did one dab of hot glue on the pixhawk and pressed the cord into it so no pulling on the pixhawk connectors. I swear this alone makes the copter about %50 less prone to a mechanical error and crash. Good luck happy flying!

                  • Waladi

                    Yes I've been using for a couple months... it seems to work very very well. 8-10 sats within a minute or two. 16-20 sats after a 1-2 minutes in the air. 1.2 HDOP on average so very good. The physical size of the plastic case is about 5.5 cm. I did not take it apart but I can see the antenna looks like 2cm across. Not real big but seems to be all it needs :] 

                  • Hi Richard,

                    Are you saying that you already use the gps and it work great?
                    Because I might try it since it's hard to find the GPS cover that can be used with large antenna such as 50x50mm CSGshop version.

                    Have you open up the cover and inspect the size of the antenna?

      • Discovered the Cause!

        Thanks guys for the feedback,, I think I have found the problem.

        I mentioned in my earlier post that the force of hitting the fence caused my camera to propel through the hole in the fence into my neighbors yard..

        Indeed, there was no sight of the camera and it's heavy duty gimbal, (1.5 lb's total weight) and there was a large hole in the fence, and it looked like there was something in the hedge at the other side of the yard that I thought had to be the camera..

        After getting a chance to talk to the neighbor, and searching for it, it didn't turn up in his yard, what I saw turned out to a water sprinkler, not the camera..

        So back to my back yard, looked around and bingo!  the camera and gimbal were on the ground exactly below where the trouble began!   (I do have some tall weeds that was hiding it)

        This means the camera/gimbal fell off the frame causing the CG to shift radically and what initiated the flyaway, and was not caused by it.

        The camera was mounted a rides on a rail.  That railsystem supports the camera/gimbal , in the front part of the copter, and the 6S-4500 MAH battery pack was on the rear rail to counter weight the Camera/Gimbal.

         This would have made the copter very tail heavy suddenly when the camera\gimbal fell off.. 

        Examining the wreckage revealed that the gimbal was mounted on a plate that was mounted to the rail system and the screw heads had pulled though the holes, I should have put some washers. there.  I didn't realize that the pound and a half of weight could stress the plate to the extent that it did.

        At least I can repair it and have confidence that I know what happened and don't have to worry about a undiagnosed problem lurking to surprise me again.

        FYI, I am surprised that I didn't see the camera go.. A lot of stuff happened in just a second or two. I might have glanced at my ground station for an instant or something.

        This also strengthens my awareness of what can go wrong, and the danger that is present with large copters


        • Good news Richard, It's great when you know what had happen to enjoy next flyes; thank's for share your bad experience I learn more from others experiences.;) 

    • What a pitty. Some time ago, with another vers I had similar issue, but using the gps, i put a cheap camera near the gps, it lost signal and when I change to loiter the copter rolled 45 deg and flies a full trottle, I inmediatly change to stab and luky no consecuences but if you don't use gps modes it couldn't be the problem and the gps and compass gitch ocurrs before the problem, thats normal when you crash, perhaps a hardware fail? motors, props, esc, etc. all working well? interesting to know the real issue. 

  • Hi,

    I've been told that sonar altitude hold is not present on APM 2.0, due to code space, is it right? In this case, what should I do to have it back?

    Thanks a lot,


  • Sorry for asking this question late. What is PosHold wind compensation fix? Was there any issue with that flight mode earlier?

    • @Phanivyas,

      That fix is just a timer adjustment that was too low for PixHawk but good for APM. As pixHawk is running 4 times faster, the timer was 4 times too low. Main effect would have been the copter computes the wind compensation as its attidue would not have been correctly stabilized... I think you will see no difference.


      This effect should not occur. When the braking phasis is finished, pos_hold gets its current position and switches into a "loiter" state to maintain it.

      But that braking_to_loiter transition is not direct as you would have bad twitch, so there is a command mix between braking and loiter controls. and probably the copter is drifting a bit during this transition.

      Would be interesting to know if this always happens and check at a log if you have it.

      Please try again using the default pshld param (max_brake_angle = 3000 & brake_rate = 8)


This reply was deleted.


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