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.

E-mail me when people leave their comments –

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

Join diydrones


  • @Randy - have you had a chance to look into the logs I have sent you in regards to the accel issue?  I'm about to send my pixhawk back, but was hoping it wasn't a hardware issue.  I'd hate to wait for a new one to arrive only to find out there's nothing wrong with the one I'm shipping back!

  • @criro1999       

    Two things come to mind. Props need balanced or check your THR_MID  You might need to lower or raise this [ sorry I forget which ] 50-100 to adjust for the weight of your copter. I'd do the props first that might be the only problem. You really need a legit prop balancer such as

  • Dear Friends, do you have any problems to update this las firmware versión via Mission Planner?, I do, I repeatedly obtain the same error message: "

  • @John Hulsbosch

    Please see the THR_DZ setting here.  There is an adjustable deadzone around mid throttle.  Your throttle has to get outside of that deadzone to affect altitude.  That would cause a lazy throttle.  The smaller the dead zone the less lazy the throttle.

    THR_DZ Parameter - (

  • ciro1999, could be a couple of things causing your copter to climb on switching to AltHold.

    1: High vibrations can cause this.  Download and check you dataflash logs in Mission Planner

    2: Throttle Mid position.  You should be hovering at close to 50% throttle. Check the log for the youth Throttle. Out value when hovering and enter this into THR_MID.

    I have been running 3.2 for a while on my test quad and ALTHOLD is fantastic, it keeps altitude within a few centimetres (unless I go flat out, in which case it drops a little while moving but returns to set height when I stop).

    Josh, as far as the lazy throttle goes try PILOT_VELZ_MAX.

    Sorry, I don't have any useful info on the accel health problem.

  • Did anyone notice that MP 1.3.16 increased the RC_FEEL (IIRC) from min to max setting?

  • I've opened a forum thread for the pixhawk accel issues, it may help to post logs in there so the devs have one place to look:  "Pixhawk BAD ACCEL HEALTH APM 3.2 - collecting data"

    Reeeeaaaly hope this turns out to be something simple and that a dozen or so of us don't just have bad hardware.

  • That's a known issue in all "altitude_controlled" flight modes. I think some pple are working on a hadwrae and/or software fix for that.

    The best you can do for now is to find a better position for your baro sensor (flight controller) to be less disturbed by pressure changes due to the frame aerodynamism. Or maybe try to tune the altitude controller a bit better but if you make it more sensitive, the altitude drop will increase...

  • Hello all

    I have a quick question about poshold. My quad is rock solid but dose lose some altitude after fast flight. My issue is the throttle is very lazy, not very responsive in poshold. Can I adjust some settings to correct this. Cheers in advance.

  • I am confused with this, I want to buy another Pixhawk to see how it goes, but I'm not sure if it's a hardware issue.

This reply was deleted.