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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        • Randy,

          that´s what I did as you can see in param GPS_TYPE.

          The copter flies exactly like it does with GPS (and so EKF also) switched on - of course GPS-using flight modes don´t work.

          Many thanks for your great software!


  • I have an odd problem after loading rc7.   I have a quad with a QAV550 frame, has 12 inch props, runs 6S with 380KV Tmotor's and have never gotten it to fly with a solid stability. If there is no wind, it flew pretty good, but I have been waiting for no wind to do an auto tune.  I updated the firmware from rc5 directly to rc7 over the weekend and now it is practically unflyable.   (I seems to have no stability at all in stable mode.

    I will include 2 flash logs.. the first is after flashing the firmware to the 3.3rc7 and no changes except for these settings: 


    I doubt that is my problem, because subsequently I reset the board to defaults and redid all the calibrations and setup, and when I tried to do a test flight, i was just as before, unflyable.. To define unflyable, I really couldn't get off the ground because it was determined to pitch forward, or back on its back. Both attempts, (before the reset, and then there flight several hours later after re configuring)  ended in the copter flipping onto its back.  

    All the motors are spinning the right way and the props are on correctly.  It is as if I am trying to fly with no gyro, or accelerometers . I will attach the logs.  The 13.bin is the first flight on 3.3rc7 and the second 15.bin one is after I reset to defaults and redid my setup leaving the PIDS at factory.

    More about the copter:   It weighs 96 ounces 2.72 kg.   I'm set up for fpv with a go pro feeding video for FPV using 1.258MHZ. I am using a tarot gimble and of course the 3DR PIXhawk, early version.  I and using EZUhf on 433 with diversity, Taranis and using 915mhz 3DR radios for telem and a minumOSD,  I love the way it works when it is working! 

    Any help figuring this out would be fantastic! 



    • Developer

      Thanks for testing with AC3.2.1 'cuz that shows that it's really a general setup issue rather than AC3.3 related.

      It looks like some kind of mechanical issue to me although it's hard to say what the issue is.  Maybe an issue with the back left motor or esc but it could be ESC calibration is required, one motor is not starting, a connection to an ESC is broken, prop or motor spinning backwards.

  • Here is the logs from our crash 2 days ago. Again, after yaw input both rear motors turned off and the quad tipped back and landed on it's props. It is quite a large quad.

    Thank you for the help!

    2015-07-11 17-04-45.bin
    Shared with Dropbox
    • Developer

      It's most likely a mechanical issues - I'd guess the THR_MIN is too low, one or more of the ESCs needs to be calibrated or an ESC sync issue which allowed one motor to stop.

      It doesn't appear to be an AC3.3 firmware issue unless it's a very low level issue.  Have you tried it on AC3.2.1?  It's best to do this especially if it's a new vehicle so we don't muddy the waters with AC3.3 issues and new vehicle issues.

      • Hmm, that's quite interesting. I will test with AC 3.2.1. So I assume the vibration and clipping issues look acceptable than?

        It is a 1300mm quad running 28" props. ESC's are KDE Opto's so there is no calibration of them, just set the min and max pwm values as specified in the wiki.

        Thank you for your responses! Much appreciated!

        • According to the Wiki vibes are supposed to be around 15 with spikes to 30. Vibes on this log are showing over 30 and spikes to 80. But clipping, except for one portion of the flight, looks like it's not an issue as it only spikes on landing/take offs.

          I will check the throttle min, If it is an ESC issue there is unfortunately no way to calibrate them other than changing the PWM value manually

          • T3

            The vibrations are a bit too high I guess - especially AccY. I would suggest to try a softer damping (or more weight on the dampers) and to try to better balance the props. 

            • Ok, I will change the mounting and adjust the minimum throttle. Hopefully it solves the issue as this is 2 crashes so far and it's not a small quad so it does a decent amount of damage in the crashes

    • Could someone explain what the new vibration parameters are and what is a healthy and unhealthy values for it? Also, the clipping parameters. What is the danger zone? I am assuming over 100 since that is when the quad decided to flip itself?

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