Copter-3.3 beta testing

Warning #1: an issue has been found with Tower's Pause button which can cause the vehicle to fly to an old position if the vehicle has not sent a position update to Tower in some time.

Warning #2: Copter-3.3.2 fixes a bug found in Copter-3.3.1's desired climb rate initialisation which could lead to a sudden momentary drop when switching from Stabilize or Acro to AltHold, Loiter or PosHold.

Warning #3: Copter-3.3.2 fixes an issue found in Copter-3.3.1 which could lead to hard landings in RTL or AUTO if the WPNAV_SPEED_DN was set too high (i.e. >400 or 4m/s) and/or the WPNAV_ACCEL_Z was set too low (i.e. <100 or 1m/s/s).

Warning #4: a bug was found in Copter-3.3 which could cause a sudden crash if you abort a Take-off initiated from a ground station.  Video description is here.  The bug is fixed in Copter-3.3.1 so we recommend upgrading.

Note #1: AC3.3-rc8 corrected a long standing bug in the HDOP reporting.  HDOP values will appear about 40% lower than previously but this does not actually mean the GPS position is better than before.
Note #2: if upgrading from AC3.2.1 the vehicle's accelerometer calibration needs to be done again.
Note #3: set SERIAL2_PROTOCOL to "3" and reboot the board to enable FrSky telemetry like in previous versions.
Note #4: the wiki will be updated over the next few weeks to explain how to use the new features

Copter-3.3.1 is available through the mission planner.  The full list of changes vs AC3.2.1 can be see in the ReleaseNotes and below are the most recent changes since AC3.3.

Sadly this version (and all future versions) will not run on the APM2.x boards due to CPU speed, flash and RAM restrictions.

Changes from 3.3:

1) Bug fix to prevent potential crash if Follow-Me is used after an aborted takeoff

2) compiler upgraded to 4.9.3 (runs slightly faster than 4.7.2 which was used previously)

Changes from 3.3-rc11:

1) EKF recovers from pre-arm "Compass variance" failure if compasses are consistent

Changes from 3.3-rc10:

1) PreArm "Need 3D Fix" message replaced with detailed reason from EKF

Changes from 3.3-rc9
1) EKF improvements:
    a) simpler optical flow takeoff check
2) Bug Fixes/Minor enhancements:
    a) fix INS3_USE parameter eeprom location
    b) fix SToRM32 serial protocol driver to work with recent versions
    c) increase motor pwm->thrust conversion (aka MOT_THST_EXPO) to 0.65 (was 0.50)
    d) Firmware version sent to GCS in AUTOPILOT_VERSION message
3) Safety:
    a) pre-arm check of compass variance if arming in Loiter, PosHold, Guided
    b) always check GPS before arming in Loiter (previously could be disabled if ARMING_CHECK=0)
    c) sanity check locations received from GCS for follow-me, do-set-home, do-set-ROI
    d) fix optical flow failsafe (was not always triggering LAND when optical flow failed)
    e) failsafe RTL vs LAND decision based on hardcoded 5m from home check (previously used WPNAV_RADIUS parameter)

Thanks for your testing!

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      • Hi Greg.
        Thank you for taking your time to answer.
        The problem I have is that Tower is not possible to perform the mission because it allows the maximum radius is 50 meters, in APMPlanner2 the maximum radius is 255 meters and MissionPlanner can not send the mission to drone because it gives an error; Looking at the complete list of parameters see that CIRCLE_RADIUS Variable accepts at most 10000cm do not know if I can define it by a larger number, I need it 40000cm.

        Thank you.

    • What are you using to setup you flight, Tower, DP or MP?  Might want to take the question to the appropriate forum for whichever you are using.

  •  Hello I just loading 3.3rc11 a auav-x2 and I have an error on the altitude (altasl) or what is the mutli task planner before takeoff?
    3.3rc11 works perfectly on my pixhawk

  • Hi guys, here is a log for reference in case this is useful.

    And sorry Randy, I know you generally only want to see frames that are already proven with 3.2.1, but I thought this one might interest you. It's a 400mm-or-so Y6 I have been having an awful time getting to fly stable. The experiment is to see how small a decent portable DIY photo mapping craft can be.

    I have been unable to autotune due to significant drift in Alt Hold that I don't see in Stabilize, at least not as consistently. And it doesn't seem to be just CoG since it's not always the same direction. So I suspected vibes. Looking through logs, every one has z-axis clipping on the Vibrations 3.3 screen! The Pixhawk is isolated by 2 layers of Kyosho gel pads at the corners as an experiment. I may run out and try one layer quickly to see if it's simple as that.

    What are your thoughts? Does it just look like an unstable frame?

    2015-09-11 10-57-40.bin
    • Just try THIS latex foam it does miracles :) 

      I have a tricopter which I fly between the trees and tree brunches, well once  after a "small" mishap which involved flipping and falling I was able to get the copter in the air without physically coming to it. When I finally flew it back to the base I was shocked to see that a good 1/3 of a CF prop on motor #1 was missing, yet it flew rather well :D 

      I go though a lot of props with my flying style and I like CF T-style props, I found a way to source those from china for cheap, but the problem is those are never balanced and with the foam I referenced I yet to have to balance one of those, no clipping and vibes are below 2 on x/y and below 4 on Z.... 

      • this Pixhawk is VERY well isolated using Kyosho Zeal pads at the corners. To be honest I'm pretty blown away that it flies so poorly. It's an Electrohub Y6, really neat frame with simple 1/2" wood arms. Motors are SunnySky X2212-980kv, battery is 4S 5000mAh at 523g. Out front is a gimbal with GoPro.

        Since 3.3 has better accounting for vibes it seems like a good test case. The issue is I can't figure out where the vibes are coming from, potentially simply something with the frame assembly itself.

        Here's another log. vibes on X and Y look fine, while Z looks just crazy.

        2015-09-11 12-54-17.bin

        • Check for motor bell play, it will cause horrible Z vibration when X and Y look great.

          One crash can cause play to develop.

          The motor bell play causing Z axis vibration was mentioned as some thing to be added to the wiki, but has not yet.
          • Thanks for your suggestion - I checked the top rear motor and there was indeed play. So I have that resolved now. A subsequent flight felt much smoother. It still drifts away in Alt Hold with no wind, but it's possible that has to do with CoG. This one has been very tricky to balance.

            Here's the log in case you're curious.

            2015-09-11 18-17-13.bin

            • crayfellow,

                Are you using a Y6 or flat frame?

              For my Y6's, these scales make it very simple to get COG as perfect as it can be.


              • this guy is a Y6 (X2212-980kv, APC 9x4.5MR, 4S 5000mAh, gimbal/GoPro). I will take a look, thanks!

This reply was deleted.


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