ArduCopter 3.2 Released

ArduCopter 3.2 (aka APM:Copter) has been released as the default version replacing AC3.1.5. This is the exact same version that we invited all users to test two weeks ago.  Users who wish continue using AC3.1.5 can find it under the "Pick previous firmware" version on the MP's Install Firmware screen.

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 support 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 to 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 CommandYaw, Thor's Zombie Run&FollowMe, Phanivyas's Test, Rob's TradHeli, Christian's Test1&Test2, Balloon'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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  • Would I be right in saying that the IMAX values are the max values that manual tuning via a channel knob could impart to the tuning?

  • @Vinscopter

    I had a similar problem because Mavlink was not connecting, It turned out to be a damaged GPS cable. 

  • Developer


    The new firmware should certainly work on the Pixhawk.  Most of the dev team is only flying Pixhawks now.  It's hard to say what the problem is, Are there no sounds or LEDS like those shown on this wiki page?  Failing that, perhaps try to connect with the mission planner's Terminal screen and hopefully the reason for the failure will be displayed.

    If you don't have a buzzer attached, could you please attach one because that may provide the answer as to what's going on.

  • Developer

    @LarryField, @ThatJoshGuy,

    Sorry, I totally missed your follow-ups regarding the accel calibration problems.

    Can you guys send me a log of you copter?  Ideally set the LOG_BITMASK to "131070" which is "All+DisarmedLogging".  I'll send you a friend request including my email address.

  • Hi Randy,

    We have 3DR PIXHAWK and it is working great with firmware v3.1.5 on our Quad. But when we try to upgrade to v3.2.. we get the firmware upgrade success tone. The indicator light goes white and Mission Planner is not getting connected for us to go any further. We are not able to get to the point of calibration. Not sure what we are missing to make it work.

    Is the new firmware version only for APM Ardupilot boards? Is there any other procedure that we are missing to upgrade onto the PIXHAWK board. We are really excited to test the new firmware. Hope to see it work.. 


    Satya & Vinodh

  • Developer

    Hi Richard Kennedy,

    the parameter you are looking for is WPNAV_SPEED in loiter. You will get an acceleration of 7.5m/s/s (around 30 degrees).

  • Can someone please explain the function of IMAX . I see values from different sources showing values that vary between 5 and 1000 ?

  • Hi Team, I have a question re autotune, I fly a 12 pound camera X8 setup am I better off Autotuning under full load(With Camera onboard) or Autotuning without?

  • Randy

    On another topic I see Pilot_VelZ_max  ... why isn't there a Pilot_HorZ_max? That is to say I'm trying to still have the aggressive max 45 degree pitch forward however the quad will soon be going much faster than I'd like and much faster than the baro likes to deal with. If I manually control it to keep it under 15 mps or so it's fine. But that's sort of labor intensive to keep the stick in the exact spot. It would be nice if I could push it full forward and know it would max out on it's own at 15 mps yet still get the 'hole shot' acceleration the 45 degree pitch forward allows. I tried the dual rate on my TX but that really doesn't do the trick it kills the hole shot and still goes above 15 mps it just takes longer. Sorry for the question I don't see anything in the wiki or the full param list mentioning any max horizontal speed for pilot controlled flight only guided. Am I missing it? Thanks

  • Developer

    @Richard, sounds like you've certainly taken enough care of the compass so surely it's fine.   In my limited experience with the 4-in-1 ESCs, their interference is less than individual ESCs.

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