ArduCopter-3.1 released!

After months of testing AC3.1 is finally available in the Mission Planner and GitHub.

Warning #1: If the vehicle is left landed (but armed) while in AltHold or Loiter mode for more than a few seconds, the vehicle may suddenly jump into the air the moment the pilot raises the throttle above zero.  The reason is the baro altitude may fall while the vehicle is sitting on the ground.  In AC3.2 this bug is fixed because we reset the target before take-off.

Warning #2: Motors will spin (slowly) by default as soon as the copter is armed!  You can switch this feature off by setting the MOT_SPIN_ARMED parameter to zero.

Warning #3: if you see "Bad Gyro" on the HUD then you may have a blown 3.3V regulator.  See this thread for details.

Warning #4: if you use a sonar set the SONAR_GAIN parameter to 0.8 or lower

Warning #5: Trad Heli users should now connect their main rotor ESC to APM's RC8 output

Warning #6: Trad Heli BUG causes loss of collective control in ACRO mode if swash type set to flybarred (i.e. not flybarless).  Will be fixed in AC3.2.


The major improvements over AC3.0.1 are (full list here):

1. Pixhawk support (Tridge & PX4 development team)

2. Autotune of Roll and Pitch gains (Leonard/Randy)

3. Drift mode (Jason)

4. Improved Acro (Rob/Leonard) and new Sport mode (Leonard)

5. Arming, Take-off, Land in Loiter or AltHold

6. TradHeli improvements (Rob) including:

a) support for direct drive tail rotors

b) smoother ramp-up of main rotor

c) reduced collective for better control in stabilize mode (STAB_COL_MIN, STAB_COL_MAX params)

7. Support for SingleCopter (Bill King)

8. Performance improvements resolve AltHold troubles for Hexa & Octacopters

9. Safety Improvements:

a) GPS Glitch detection (Randy)

b) Motors spin when armed (Jonathan Challinger)

c) crash detector shuts off motors if copter flipped for 2secs

d) batt failsafe option to RTL instead of LAND, gps failsafe option to trigger AltHold instead of Land

e) more pre-arm checks of inertial nav speed,

10. Bug fixes:

a) optical flow working again (although performance is still not great because not integrated with inertial navigation)

b) ROI working (use DO_SET_ROI command)


How to upgrade:
Click on the MissionPlanner's Initial Setup >> Install Firmware screen.  The version numbers should appear as "ArduCopter-3.1", then click the appropriate frame icon and it should upgrade as per usual.

Special thanks to Marco and the many beta testers on the AC3.0.1 thread who put their copters at risk during the testing of this new version and uncovered many problems so that you don't have to!  Here are some of their videos: loiter in wind, patio sonar, autotune, autotune2, roi, beach, acro, vrbrain, tricopter, train spotting, radio failsafe, the tree, double loiter


If you haven't seen it recently, please check out the ArduCopter wiki.


Feel free to post comments below and we're going to use the new APM Forum for support issues so please post your support requests there.

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        • Personally,I would like them to make better and cheaper controllers not to end for them...

          • They will not end. There will always be enough people who won't mind paying $1000 more for a device that has a nice shiny aluminum case and comes in nice packaging. Some people are geared to spend more money; they will only buy expensive items even though the same can be done at much cheaper price. You may laugh at it but can't change this fact...

            • I have owned two DJI A2's and the rest pixhawk
              I see no difference between the two but here is what you are missing. I believe if you can fly well, like manual mode no stabilization . In any orientation and have some technical knowledge , no difference. But for the guy who has limited knowledge and has 6 gains to enter which can be found anywhere, some DJI products are worth it. There are bugs in everything, I fly mostly hard 3D helis, but have read these forums cover to cover. Almost all issues (ALMOST) not all are user/ pilot error. So there is more than one is better then another. For me, I take Pixhawk every day and I fly one on my Evo 800. But not for everyone. DJI is more then just a shiny case.....I think we should learn how to fly first very well, before ever switching on autopilot. That is what makes me nervous when I read some of these posts.
      • Thank you Randy.
  • I just test Octa Ironman 1000 for my Customer.

    • ooops moving my post


  • I may be late to the "Atta Boy" party but who ever re-did the log browser in Mission Planner, you're a BOSS! so much easier to go thru attributes and params with that little tree menu on the right of the Screen.

    Also "ATTA BOY" for who ever created the Drop Down List of common config params in the Current Mission Planner, i have been hoping for something like that for a while now, my only question since i seemed to have missed that memo, do those profiles work for APM's or Pixhawk? or both? i am Quite tempted to Bite Eve's Apple and load one of those on an F450 with APM 2.6. :P

    • +1 on the latest Logging features.  Awesomesauce!  So easy to flip through logs now!

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Aug 25