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)

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –


      • I had same issue with disarming in PosHold mode. Unable to disarm after landing (probably I have landed on another altitude), but switching to stabilize helps to shutdown.

  • I use Pixhawk with external compass, and caught one bug (latest 3.2 rc7):

    1. Power copter in upside down position (I have battery at bottom, so I rotate to connect it)

    2. Wait for melody

    3. Rotate it back into normal position

    Now, I can't arm ... get "Alt disparity" warning. But, if I take copter and "wave" it, barometer becomes fine and arming fine.

    • Developer

      Yes, I agree with Marco that it's not a bug.

      The "Alt disparity" is a check that the inertial navigation and barometer are in sync.  They can take a while to sync up after starting the vehicle and it'll probably take longer if the vehicle is flipped over.  I suspect that waving the vehicle didn't help but rather it was just the time spent waving it that allowed the two to converge.  I'll update the pre-arm checks wiki page with the new checks added in AC3.2.

      • Agree, this is not a bug, this is feature. After powering and rotating back I can wait up to 2-3 minutes and nothing happens, just yellow light blinking. But, if I take copter and wave it - immediately light becomes green and I can arm and fly without any troubles.

    • Developer

      I don't think it's a bug, you should never connect the battery with the drone in that position, in general it's a rule.
      During the initial phase the drone must remain motionless, and not upside down, for a few seconds after you connect the battery connector.

  • If I turn copter around itself, it doesn't keep position. Doesn't use compass for this? Why?

    • Developer

      Are you using version AC3.2 or AC3.1.5?  AC3.2 does a better job of holding position when rotated like this.

      The reason that it doesn't hold position perfectly is because there are multiple things that make it drift that work on different axis of the vehicle.  This includes wind, the vehicle's COG can also be slightly off causing a drift in one direction, there are also accelerometer biases that can make it think it's moving in another direction.  When the vehicle is still and not turning, we build up a single set of 3D corrections that account for all these disturbances but when the vehicle is turned, some of the disturbances rotate with the vehicle (like accel biases) but some do not (like wind).  It takes a short amount of time for the corrections to build up again (using the GPS) to counter the new combination of wind, cog, biases.

      • Thanks for answer. My english is poor. :( I use AC3.2 RC7. Position holding is very good.

        I talk about direction. Why not keep direction? Uses only gyro for yaw axis?

        • Developer


          Ah, it's designed to work that way.  If it's heading is yanked more than 10degrees from the target it drags the target around.  I think we thought it would be safer this way because it won't whip back around to it's previous heading once yaw control is restored.

          P.S. Your english is totally fine.

    • What mode do you use? Loiter? PosHold? AltHold?

This reply was deleted.


Shivchand Jaysaval liked Shivchand Jaysaval's profile
Aug 25