ArduCopter 3.2 ready for wider use

After months of testing, ArduCopter 3.2 (aka APM:Copter) is ready for widespread use and we invite all users to give it a try.  In order to manage the support load at first it will be available only through the Mission Planner and APM Planner2's Beta Firmwares link.  This link is visible from the regular "Install Firmware" page if you check the "Advanced View" on the Config/Tuning >> Planner page.  On APM Planner2 the "Advanced View" it is under the File menu.

In about two weeks we plan to replace AC3.1.5 with AC3.2 as the default version dispensed by the ground stations.

The full list of changes can be found in the ReleaseNotes but here are the highlights:
Flight Mode Enhancements:

  • PosHold flight mode: similar to Loiter but with direct response to pilot input during repositioning
  • ACRO mode handling improvement EXPO (for faster rotations)
  • Drift mode uses "throttle assist" (similar to AltHold)
  • Smoother transitions between flight modes (i..e when entering Loiter or RTL from high speeds)

Mission Enhancements/Fixes:

New Sensors/Devices:

Safety Features:

  • EKF/DCM check will switch to LAND mode if heading error > 60deg for 1 second
  • Baro glitch detection
  • Pre-arm check for Gyro calibration success
  • Pre-arm check that internal & external sensors (gyros, accels and compass) are consistent (Pixhawk only)
  • Parachute support (Pixhawk only)
  • Feedback to Pilot when taking off in AltHold, Loiter, PosHold (i.e. motors spin up a little as throttle is raised)
  • EKF (new attitude and position estimate system only used for reference in this release)

Bug Fixes:

  • Pixhawk GPS driver buffer overflow that could lead to missed GPS messages
  • Pixhawk I2C bug that could lead freeze up if I2C bus is noisy

Known issues/Warnings:

  • Pixhawk users will need to recalibrate their compasses
  • PosHold won't show up as option on FlightMode screen if you have an old version of mission planner.  Please select Help > Check for Updates
  • Landing detector is more strict meaning it may take longer to disarm after RTL, AUTO
  • Set THR_MID parameter especially if you have a very powerful copter because "Feedback to Pilot" raises throttle to 1/2 of THR_MID
  • Spline twitches slightly as it passes a waypoint especially if WPNAV_SPEED is set > 500.
  • Dropped support for NMEA and SIRF GPS on APM boards (ran out of Flash space)
  • Dropped ssupport for sonar for MultiCopters on APM1 and TradHeli on APM1 & APM2 (ran out of Flash space)

If you hit issues, please post them in the APM Forum and include a dataflash log file if possible.

Special thanks the Marco and the Beta Testing team from the AC3.2 beta testing thread who put their copters at risk in the pursuit of a smooth, safe release.  Here are links to some of their videos: Marco's DJIs900, Holger's Water Tower, Josh's Acro, Ray's TradHeli2&FPV, Raph's Hawaii, PhillS's CommandYawThor's Zombie Run&FollowMePhanivyas's Test, Rob's TradHeli, Christian's Test1&Test2Balloon's Spline, JimJ's FPV, Ultrojo's ROI & Spline&FollowMe1&FollowMe2, Troy's Mission

Thanks also to the code contributors to this release including Tridge, Jonathan, Leonard, RobL, Paul Riseborough, MichaelO, Julien Dubois, David Dewey, Andrew Chapman, Emile, Allyson and many more.  If you want to get involved check-out our dev wiki.

E-mail me when people leave their comments –

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

Join diydrones


  • Denny Rowland

    Bill fixed that compass calibration not working in APM Planner for the Mac. It's here

    fyi if your running OS 10.10 make sure you select the box that says 'don't ask again' when it mentions it's not from the App store 

  • I was trying to re-calibrate but it wouldn't take.

  • Moderator


    Frankly I liked method 2 best. Yes it took more time, but let's face it, if done right you only need to do it once. I think the bigger problem was that the Mission Planner side of the process was not very well documented which led (or leads) to people not knowing what to expect from the process. Nor is there a really good explanation of what are acceptable numbers when calibration is finished. leading to people flying with poorly calibrated compasses.

    For that reason I think filling the whole globe is simpler, though more time consuming, for people to complete correctly. Randy's video is very helpful for understanding what must be done with the aircraft, but doesn't adequately explain what's happening in the mission planner, nor does it explain what are acceptable values for X,Y and Z offsets. Good offset values are well documented for APM 2.5/6, but not for Pixhawk.


    Nathaniel ~KD2DEY

  • @Craig

    Thanks for your reply. The problem is there seems to be a lot of inconsistency in the results. There is another thread with a lot more info on this.

  • Developer

    @Darell.  You must re-calibrate your compasses when you update to 3.2 

  • Developer

    Mission Planner used to collect samples for 60 seconds and then run the calibration calculation.  It was possible to get a bad calibration because the vehicle would not be rotated in each direction.  Awhile ago we made it so that the compass routine required samples to be gathered from all over the sphere around the vehicle and there was a graphic display to help the operator point the vehicle in all directions but that could take a long time to gather enough points.

    Now what we do is speed up compass messages and turn off most of the other messages.  We also start calculating the solution after one second and perform the calibration continuously.  The calibration stops automatically a) when points have been gathered with the vehicle pointing in all directions and b) when the solution converges.

    Feed back is appreciated.  Thanks!

  • Could you please check mission planner version.
    It must be latest , i have the same issue with compass that i have managed to upgrading mission planner
  • Tried 3.2 through APM Planner 2.0 but it won't take a compass calibration now. Just continually says compass not calibrated. If I go back to the old firmware it's fine.

  • @Terry

    I noticed as well in AC3.2 the compass calibration is time limited and completes before I think there are enough readings taken.

  • I can't get the Motor Test on Initial Setup to work with my APM 2.5 and ArduCopter V3.2.

This reply was deleted.