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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          • Thanks for the response Randy!!

        • Reuben,

          I am glad you mentioned that, now i await the answer. Thats Exactly how i would like geo Fence to work, get to the limited/ceiling and stay there. i wasnt aware of any problems with geoFence at this time, i thought they had all been corrected.

          As i think of this request, it occurs to me that it would be a "nice to have" feature for beginners to have a trainer mode where things like distance and Altitude is governed  & Has programmable limits, thus allowing N00BS like me to have a better chance to learn with a safety net, instead of crashing a few times.

      • Ok i thought Geofence was just a failsafe, didnt realize i could cap the ceiling for flight. what i dont want is it to trip the failsafe and RTL, so i guess i will have to send it into Loiter or something as a response to hitting the ceiling? thanks for your answer!

        • There are difference type of setting fence. You enable it thru ch 7 or 8. Link

          • yeah thats what i dont want, a simple limit to altitude and distance is fine but i dont want it to RTL or Land, i'd rather it just Alt Hold or Loiter. i was hoping for a parameter that, when set, would limit the Arducopter to the set values. oh well, it would be nice to have something like that for beginners.

  • Have you found anyway to get the DX18 controller working?

  • Hi there,
    I hope this question is in the appropriate forum. Some weeks ago, a "hybrid" type loiter was mentioned by Marco and a few others. I read that the feature may possibly be included in a future software release.
    Does anyone know if this feature is on track to be included and if so, the approximate progress of it?
    Thanks in advance crew!
    • Developer


           It's on the list but we haven't started integrating it yet.  AC3.2 will be the next big release but it's quite far off still as it will include quite a lot of changes especially for the higher performance CPU on the Pixhawk.

      • thanks randy!

        the next release will be the end for wookong and others high end plateform

        • I beg to disagree on this. They've always something in mind. 

This reply was deleted.


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