ArduCopter-3.0.1 released!

ArduCopter 3.0.1 has been released and is now available in the Mission Planner,, GitHub and the new Downloads Area.

Warning #1: Compass calibration and reducing interference is far more important than with 2.9.1b

Warning #2: GPS glitches can cause sudden and aggressive position changes while in loiter mode.  You may wish to reduce the Loiter PID P to 0.5 (from 1.0) to reduce aggressiveness (see image below of where this gain can be found in mission planner).

Warning #3: optical flow is not supported but will be back in the next release (AC-3.0.2 or AC-3.1.0).

Warning #4: loiter turns does not maintain altitude.  This bug will be fixed in AC-3.0.2.

Warning #5: This release has only been lightly tested on Traditional Helicopters.

Improvements over 2.9.1b include:

  • Inertial Navigation for Loiter and Auto meaning much more accurate control (Randy,Leonard,JonathanC)
  • 3D navigation controller follows straight lines in all dimensions between waypoints (Leonard,Randy)

         WPNAV_SPEED, WPNAV_SPEED_UP, WPNAV_SPEED_DN, WPNAV_ACCEL allows configuring speeds and acceleration during missions

  • "compassmot" to compensate for interference on compass from the pdb, motors, ESCs and battery.  (Randy,JonathanC) (Set-up video here)
  • Safety improvements:
    • simple Tin Can shaped Geo Fence
    • pre-arm checks to ensure all calibration has been performed before arming (can be disabled by setting ARMING_CHECK to zero).  (video description here)
    • GPS failsafe - switches to LAND if GPS is lost for 5 seconds
    • stability patch improvements to stop rapid climbs in very overpowered or overtuned copters
  • Circle mode improvements including "panorama" when CIRCLE_RADIUS set to zero (Randy,Leonard)
  • SONAR_GAIN parameter added to allow better tuning of sonar surface tracking
  • CH8 auxiliary switch (same features as CH7)
  • works on PX4 (some minor features still not available) (Tridge,PatH)

How to upgrade:

1. Make sure you are using Mission Planner 1.2.59 or newer (get it here)

2. Click on the MissionPlanner's Hardware, Install Firmware screen.  The version numbers should appear as "ArduCopter-3.0.1", then click the appropriate frame icon and it should upgrade as per usual.

3. Reduce the Loiter and Alt Hold PIDs if you have modified them from the defaults.  The modified PID values for the 3DR frame can be seen in the image below.

Note: Nav parameters have been combined with Loiter so do not be concerned if you can't find them.


4. Although not directly related to this release, if you purchased an APM prior to March of 2013, update your PPM encoder to the latest firmware (instructions here).

5. Try out the new version in stabilize mode first, then alt-hold, then loiter and finally RTL and Auto.

Numerous How-To videos are available:

Special Thanks to MarcoDaveC and the large number of testers on the pre-release thread who put their copters at risk during the extended testing period.  Some of their videos can be found hereherehereherehere and here.  Thanks also to MichaelO for the MP changes required for this release.

All feedback welcome.  Please put your questions, comments (good and bad!) below.

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  • Developer

    Here's a preview of the land-in-loiter feature that Leonard and I put together over the weekend and will be out with AC3.1 (no estimate on when we will enter beta testing yet).  The (optional) props-spinning-when-armed feature was added by Jonathan Challinger.

    To detect the landing it looks at the motors hitting their lower limits and the climb rate being between -20cm/s ~ +20cm/s

  • Yay, my turn for help. I did a brief flight testing out new motors, vibration and Mu Metal. I noticed right off the bat all the motors didn't spin up at the same time. After a little more throttle they all kicked in but... there is always a but. Roll wanted to drift to the left, with some stick input I was able to steady things. My understanding is either I need to re-calibrate, power up on a flat surface and not the grass or the Moon Gel isn't flat. So I figured I would ask the gurus (you guys) for guidance. Thanks.

    2013-07-28 19-03 1.log

  • Hello all. I have problems with 3.0.1 (MP current FW for quad) three days. Loiter very bad.

    The unit began circling clockwise (as viewed from the bottom) with increasing radius. Waited 5 meters and corrected position, and then circling again. Satellites in those days was first 6-9 and 10-11, and today is also bad. At first, when today was 9 satellites, then held, but after five minutes of flying in stable mode with 11 satellites again began circling. HDOP 2-3. If this is the direction (compass) persisted. In what could be the problem? Now i have not logs... This has been observed for several people.

  • MR60


    I made the 3.0.1 upgrade. Checked quickly some data in tlogs and would like other opinions on these two graphs.

    One is the VCC (was bugged in 2.9.1), I'm using the 3DR PM that should deliver a rather good and constant voltage, however I see small variations and a general line below 5V. Is this expected ? (I just have a buzzer and two lwo power diodes connected on APM, no servos)


    The second graph is a check of the magfield. I notice it varies according to throttle quite a bit. Is this normal and/or expected ?



    Finally a last question: in 2.9.1b i noticed i had twice as much hover fly time than now with 3.0.1. How can this be explained ? (exact same copter).


    I'm using an APM2.5 equipped 3DR Hex with 880 Kv motors, a 4S 5000 mA battery, and 10 X 4.5 props.  It's loaded with v3.0.1 firmware.

    Compassmot is 54% and the noise is well within limits.

    I've had a bad case of the wobbles over the last couple of weeks. It seems to be getting worse.  The hex gets into an oscillation and pitches heavily fore and aft 5 or 10 times before it smothes out.

    I've gone over the logs using that great new log reading HOWTO on the Wiki to see if I could figure out what is causing it.  All I can see is that there are lots of strange wobbles.  The image below is a snip out of the logs that I have included.


    I backed off the 'P' in Rate Roll and Rate Pitch and set them from the default 0.1500 down to 0.1175..  (Any lower and the thing gets really sluggish.. And, it still wobbles). ---  The Rate Roll and Pitch 'I' values are the default 0.128 and 'D' is the default 0.0040

    The logs below are from a flight today.  It was a bit breezy (10 - 20 Km winds).  But I've had smoother flights in the past in even stronger winds.

    Any idea of what I should check to fix this?   Thanks in advance....

    2013-07-27 17-05 1.log

  • I'm still on 2.91b at the moment. After many problems and failures I had in the beginning, I'm a bit hesitant to made the change, reading some of the problems here.

    I believe, I got the vibrations under control now. Still flying EPP props and waiting for new CF props, but my dampening system works well. After I removed the fibertape reinforcement around the cables that go to the APM, the vibes went down again.

    Some flightlogs and videos:

    But - I have also read lots of good about 3.0.1, so here are some questions:

    1. If my copter ran nicely under 2.91b, how big is the risk that I get some weird flyaway or crash under 3.0.1?
    2. Can I use my 2.91b PIDs or do I have to do the tuning process all over again?
    3. I read a lot about loiter being improved excessively. My copter now loiters pretty ok, even in medium gusty winds. However, I noticed that it gets really "active". Hard to describe - when I hold the copter manually on a sport in stabilize mode, I hear a very uniform motor sound. When I switch to loiter, it first drops a bit and then you can hear the APM doing really a lot with the motors, even in zero wind conditions. As a result, the copter appears a bit jittery and so does the video, but it is within tolerable boundaries, usually. Is this a tuning issue or a 2.91-issue? Can I expect this behavior to cease in 3.0.1?

    I'm yet torn about should I make the change to 3.x or not and hope for some enlightenment here :).


    2013-07-28 00-39 1.log

    2013-07-28 00-49 4.log

  • Ok Guys more question to add to the learning curve ... Why on my HEXA  do three same rotation motors run hotter than the other three opposite rotation motors ?  is it something in the settings that's causing it ?

  • Quick question to the experts. Is the RATE_YAW_IMAX default value correct? 

  • Quick question regarding max pitch and roll angles:

    How can I constrain the max pitch and roll angles when flying in auto, stable, and loiter modes?

    I had an issue when flying an auto mission where the headwind was strong enough that the copter couldn't maintain the requested speed and it leaned so far into the wind that it couldn't maintain altitude at full power and almost crashed.  Can I limit the max pitch angle so this won't happen?  I assume if I could, in a situation like I described above, the copter would just travel slower, but would maintain altitude.

    I'd also like to restrict the pitch and roll in stable mode as it's a bit too much right now.


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