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.

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

Join diydrones

Email me when people reply –


      • wow that is toilet bowling!! No mine is more like a 4 foot circle. But yes the gps is on a mast and arrow forward. No wires near it. All in 1 esc all the way at the bottom. So must just be the motors I guess. So this happens when the two compass start to diverge from each other after initial arming? I will try the motor compensation like in your video that was a huge improvement. Overall however it flies fanatic. The way it brakes in pos hld while I'm yawing is particularly amazing! 

      • Even the hawk was toilet-bowling

      • Hi Randy can this version still be used on APM ver 2.5

        regards George

        • Developer


          Yes it can!

  • Hello guys,

    I flown the 3.3 dev, due to the accel health issue,for about one month.( Andrew's tip)

    i see that  the 3.2.1 try to reconfigure the IMU, but the "wrong" for my issue ( cause it's seems that  it's the lsm that cause issues) if i well understand ;-)

    I'll try the new one as soon as the sky stop to cry :-(

    • Developer


      Sorry for the slow reply.  Unfortunately we don't have any software fixes for the lsm303d accelerometer failing.  Not in master and not in AC.3.2.1 I think.

  • Flew 6 full battery test flights this weekend and only one small problem.  I had to abort an autotune due to wind and landed in autotune rather than switched low to revert to previous PIDs.  The motors did not shut down and it flipped over, operator error.  After a successful calm morning autotune the aircraft flew very well with no glitches in any of the flights. I flew in Stab, Loiter, Alt hold, Drift.  No Auto, but did try Land and RTL multiple times.  Feels very stable and predictable, thanks for all the work you do. I just started this obsession in December and have had a great time.  I'm in the process of integrating UAV's and UGV's in my High School Mechatronics curriculum, it's been a steep learning curve.

  • I've been seeing a lot of long loops in the Log ANalyzer for this version. Think there are more than there were in the regular 3.2

    Here is the log of the Tmax.


    Something strange... I switched from Poshold to stabilize and back to poshold just before takeoff. The rise in loop time starts as I am taking off.

    Then another Poshold appears, without having go to and come from some other mode. This by the way would probably be where the power surge happens on first take off, although I really didn't notice it this time (doesn't mean much that I didn't notice it, I was focused on something else).

    The MaxT number rises to 1.5 and back down to some small number where it sits calmly for the rest of the flight.


    • Developer


      It's possible although the PM message picks up the arming delay so it's best to throw away the next PM message after arming.

    • Hi Randy,

      Some good improvements on version 3.2. We have really seen the difference on larger heavier multi-rotors when being able to reduce the "Jerk" Settings.

      We are having the pitch drift problem as well. Turning on the Kalman Filter seemed to help but maybe was a coincidence as I was just flying a different vehicle today and the drift returned.

      This morning had odd heading drift when arming the motors (motors not running) switched back to 3.1.5 and the issue went away.

      Will try the newest Beta Version tomorrow

This reply was deleted.


DIY Robocars via Twitter
How to use the new @donkey_car graphical UI to edit driving data for better training
DIY Robocars via Twitter
RT @SmallpixelCar: Wrote a program to find the light positions at @circuitlaunch. Here is the hypothesis of the light locations updating ba…
DIY Robocars via Twitter
RT @SmallpixelCar: Broke my @HokuyoUsa Lidar today. Luckily the non-cone localization, based on @a1k0n LightSLAM idea, works. It will help…
DIY Robocars via Twitter
@gclue_akira CC @NVIDIAEmbedded
Nov 23
DIY Robocars via Twitter
RT @luxonis: OAK-D PoE Autonomous Vehicle (Courtesy of zonyl in our Discord:
Nov 23
DIY Robocars via Twitter
RT @f1tenth: It is getting dark and rainy on the F1TENTH racetrack in the @LGSVLSimulator. Testing out the new flood lights for the racetra…
Nov 23
DIY Robocars via Twitter
RT @JoeSpeeds: Live Now! Alex of @IndyAChallenge winning @TU_Muenchen team talking about their racing strategy and open source @OpenRobotic…
Nov 20
DIY Robocars via Twitter
RT @DAVGtech: Live NOW! Alexander Wischnewski of Indy Autonomous Challenge winning TUM team talking racing @diyrobocars @Heavy02011 @Ottawa…
Nov 20
DIY Robocars via Twitter
Incredible training performance with Donkeycar
Nov 9
DIY Robocars via Twitter
RT @JoeSpeeds: Sat Nov 6 Virtual DonkeyCar (and other cars, too) Race. So bring any car? @diyrobocars @IndyAChallenge…
Oct 31
DIY Robocars via Twitter
RT @JoeSpeeds: @chr1sa awesomely scary to see in person as our $1M robot almost clipped the walls as it spun at 140mph. But it was also awe…
Oct 29
DIY Robocars via Twitter
RT @chr1sa: Hey, @a1k0n's amazing "localize by the ceiling lights" @diyrobocars made @hackaday! It's consistently been the fastest in our…
Oct 25
DIY Robocars via Twitter
RT @IMS: It’s only fitting that @BostonDynamics Spot is waving the green flag for today’s @IndyAChallenge! Watch LIVE 👉…
Oct 23
DIY Robocars via Twitter
RT @IndyAChallenge: Congratulations to @TU_Muenchen the winners of the historic @IndyAChallenge and $1M. The first autonomous racecar comp…
Oct 23
DIY Robocars via Twitter
RT @JoeSpeeds: 🏎@TU_Muenchen #ROS 2 @EclipseCyclone #DDS #Zenoh 137mph. Saturday 10am EDT @IndyAChallenge @Twitch
Oct 23
DIY Robocars via Twitter
RT @DAVGtech: Another incident:
Oct 23