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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  • APM 2.6  Firmware 3.2  450 quad

    Problem when going from Stab to Alt_Hld  quad drops like a rock .  I can keep it in the air with more Thrt.

    input (fast). Looking at log file you can see when Alt_Hld  comes on Thr out goes down as Thr in goes up.

    I can post log if need be...

  • 3701914472?profile=original  Yesterday when I tested my new quadcopter, I got the error message as attached file.
    Dose it affect the flying of the quadcopter?
    My configuration is as belows:  
    PC:window 7
    missionplanner ver: 1.3.17
    APM2.6 with Firmware  3.2
    GPS: M8N
    Telemetry:  Xbee Pro

  • Randy

    Yes I do have EKF on. I had a hard landing perhaps it did something to the mag on the gps. 

    You said 3.2 doesn't have fail over.....  I must misunderstand what you  said. If EKF see's it doesn't trust the external so then it uses the internal ?? isn't that failover? It's not giving up on the external and using no compass is it? Cant fly at all then... 

  • thanks Randy! :) I will try the beta soon and post my feedback to that link

  • Developer

    I've created a new discussion for the AC3.2.1-rc1 beta testing here.  Beta testing can be dangerous (mostly to the vehicle) so please don't test with your prized vehicle that would cause much heartbreak if it were damaged.  Thanks!

  • Developer

    @Richard, are you using the EKF by any chance?  If 'yes' then what you're seeing is the EKF giving up on the compass completely because it's decided that it can't be trusted.  DCM isn't smart enough to make that decision so if AHRS_USE_EKF is "0" the compass should always affect the heading but at a much slower rate than the gyros (the gyros are what's causing the fast update when you move the whole vehicle).

    We don't have failover of the compass in AC3.2 but that was a choice because a significant number of people have very bad internal compasses and we thought it could actually be more dangerous to do the failover.  AC3.3 (with EKF on by default) will have the compass failover working.

  • It does take a few seconds and does turn on the HUD. But... not as fast as when I turn the entire quad. And ... just to really keep it interesting after a few minutes Turing the external does nothing on the HUD. But turning the quad does. So it's as if it uses both at first... then only the internal after a few minutes. Hopefully it's just a bad external mag. I'll swap it out for a new one when it arrives and see if that's the issue.

    3.2 doesn't have the fail over for the compass right? Very odd the way it seems to start out sort of using the external but then doesn't at all. I didn't even think that was possible. 

  • Developer


    The response to the compass is very slow compared to the gyro so it may be that you need to leave the compass off at 45degrees for some time (like 30seconds) to see it rotate around.  If the heading doesn't rotate after that long then it may be that the external compass isn't working for some reason.  Perhaps Rob Lefebvre could have a look in the APM Forum...

  • Randy

    So I have a pixhawk running 3.2 with a gps/mag on a mast. Being as I have broken the mast several times I cut the shaft in half and connected them with a piece of model fuel tubing so it has a little 'give'. Being as it can  move a little independent of the quad I happen to notice if I twisted the gps/mag the heading did not change on the HUD.. hmmm When I set it up I select Pixhawk and it should auto detect an external mag right? When I do the calibration with AP2 at the end it says 'compasses calibrated,' [plural]  and if I look at the offsets one set is fine the other is high.... so I assumed the internal was high so it would use the external. Anyway... surely if it's using the external and I twist it 45 degrees it should do that in the hud right? I don't get it. Any idea's or things to check? Thanks!
  • Developer

    @Joe, yes the pass through should be working in AC3.2.  Please ping/post me if you find any problems.

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