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.

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  • Thanks Alex, Good advice.

  • Thanks for the pointer. 3DR removed Stabilize as one of the standard flight modes for the IRIS+ and also for the upgraded IRIS. I guess I could put it back temporarily with Mission Planner to get the actual in-flight experience and then do the adjustment as the wiki documents. Thanks for the quick response!

  • Moderator


    Follow the directions here in the wiki.


    Nathaniel ~KD2DEY

  • I just upgraded my IRIS to a an almost IRIS+ with the upgrade kit from 3DR and am running the almost released 3.2 software. Anyone have a suggestion for what I should set THR_MID to? I noticed during Alt-Hold and Loiter that it hovers with my Throttle below the physical midpoint of the Throttle stick. I guess I could just try a few values and see but perhaps there is a suggestion from the community. Thanks. Jim

  • 3DR does make a pixhawk specific MinimOSD cable here:

  • Developer

    @HZL.  You can modify this cable to work with the Pixhawk but 3DR does not make one purpose built for the Pixhawk.

  • @CraigElder..

    Whoops again.. timing and race issues have it working unreliably... ah Crag.. have you got a part  number/3DR store URL for a PIXHAWK/MiniOSD 1.1 compatible splitter cable?

         thanx in advance


  • ALSO, I have noticed the MP stays in BETA mode when doing updates.  Thanks Michael O and the rest of the DEV team!!  It was not really an issue but did cause a bit of confusion.

    I have found the opposite, when I did the update from beta it went to a release version and I had to download beta again to get Position Hold mode back.

  • @Denny, I beg to differ.  This release just blows 3.1.5 out of the water.  The smooth response of the new flight modes and additional features including follow me is just so impressive.  

    We've had our test platform in 35+ kph winds yesterday and everything went without a hitch including about a dozen planned missions using the ROI for camera control and it was really incredible to see it all work over and over again.

    Again, a big thank you to the dev team for pulling this off !  We'll be posting some of our footage soon and will provide a link to it.

  • @Denny try going to the help page of mission planner and install the BETA version.  All should work fine.  The compass calibration is shorter now and will finish on its own.  I found the values to be almost the same (within +/-10) as previous MP versions with the longer calibration on three different machines.

    ALSO, I have noticed the MP stays in BETA mode when doing updates.  Thanks Michael O and the rest of the DEV team!!  It was not really an issue but did cause a bit of confusion.

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