ArduCopter 3.2.1 released

Warning: there was a period of about 12 hours after this blog was first posted where an older version (AC3.1.2) replaced AC3.2.1 for APM2.  If you think you may have downloaded for the APM2 during these initial period, please check the version on your board by looking at the title bar of the Mission Planner (see the 5th comment from me below for a screenshot)

ArduCopter 3.2.1 has completed beta testing and has been released as the official version available through the mission planner and other ground stations.  If upgrading from AC3.2 there should be no need to re-do any configuration.

Changes from AC3.2 are listed below and in the ReleaseNotes:
1) Enhancements:
    a) reduced twitch when passing Spline waypoints
    b) Faster disarm after landing in Auto, Land, RTL
    c) Pixhawk LED turns green before arming only after GPS HDOP falls below 2.3 (only in flight modes requiring GPS)
2) Safety Features:
    a) Add desired descent rate check to reduce chance of false-positive on landing check
    b) improved MPU6k health monitoring and re-configuration in case of in-flight failure
    c) Rally point distance check reduced to 300m (reduces chance of RTL to far away forgotten Rally point)
    d) auto-disarm if vehicle is landed for 15seconds even in Auto, Guided, RTL, Circle
    e) fence breach while vehicle is landed causes vehicle to disarm (previously did RTL)
3) Bug Fixes:
    a) Check flight mode even when arming from GCS (previously it was possible to arm in RTL mode if arming was initiated from GCS)
    b) Send vehicle target destination in RTL, Guided (allows GCS to show where vehicle is flying to in these modes)
    c) PosHold wind compensation fix
    d) prevent infinite loop with do-jump commands pointing at each other
    e) pixhawk memory corruption fix when connecting via USB
    f) vehicle stops at fence's alt limit in Loiter, AltHold, PosHold (as it did in AC3.1.5)
    g) protect against multiple arming messages from GCS causing gyro calibratoin failure

Thanks very much to Marco and our beta testers who put their copters at risk over the past several weeks to help us iron out these issues.  Also Thanks to Raph for the video (this is actually a video from AC3.2).

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  • Developer

    The problem we were having only affected the APM so you will have downloaded the correct code.

    If you want to see what version of code is running, open up the messages tab below the PFD on Mission Planner when you connect it to your vehicle and the firmware version will be displayed

  • Craig, I am confused now. I updated my Pixhawk to 3.2.1 about 2.5hours ago. Which is the final correct version for the Pixhawk? What should it display in MP?
  • Developer

    The firmware on the server has been updated and is now correct.

    If you downloaded any of the APM versions of the firmware in the last several hours I recommend re-installing the firmware and verifying or erasing your parameters and re-configuring your vehicle. 

  • MR60

    Just upgraded to 3.2.1. I notice, on the bench with usb cable, and no GPS fix, that a slow and constant altitude drift occurs : from 0 meters when connecting the usb cable , going to 2.5 meters in 15 minutes and it keeps going up endlessly . Deconnecting and reconnecting the usb resets the altitude to a zero value but the drift starts again. The actual baro values does not seem to change (maybe just the scale does not allow to see small drifts), the press_temp value slowly increases.  The temperature seems stabilized after more than 20 minutes of usb connection, but the altitude continues to go up...Any idea if this is something to worry about ? If the temperature change was the only cause of the altitude drift , why doesn't tthe altitude display remain constant after a ramp up period ?

  • Developer

    We had a second problem with the build server since Randy made his post and the version showing in the planner again lists 3.1.2 as the current stable release.  At the moment if you load the code onto a PX4 or Pixhawk you will get 3.2.1 and if you are loading onto an APM you will get 3.1.2.

    We just fixed the problem a few minutes ago and in about 2 hours from now the correct version will appear in the Planners,

    I'll make another post as soon as I see that the correct version is available.

  • Mission Planner is still showing 3.1.2... I did the mistake of downgrading from 3.2 to 3.1.2 :(

  • Michael, not upgrading to AC3.2+ will not make you safer, because, as Randy mentioned here and Tridge in this thread, it is a HARDWARE issue. Unfortunately it is not possible to know if your pixhawk has a faulty MPU6k while running AC3.1.5 because the relevant tests/logging was added only into the AC3.2+ code. So, in fact sooner you update to AC3.2.1 the better it is for you. 

  • I've decided to wait on updating to 3.2 because I'm already seeing reports of accel & compass calibration issues.

  • Developer

    Keep it up and fly safe...

  • Hats off to you Randy for such an incredible contribution !

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