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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          • Not really well. It tilted hard when motor failed. Of course I was kind of expecting the failure so I was flying really low. Couldn't land it on it's feet, always fell. I think if the hex was higher, it would have been possible to take better control.

    • i had almost exact problem before and it was driving me nutz...eventually i found out it was a motor going bad and having sync was very hard to figure it out....but check your motors/ESC for intermittent failures

      • May I ask how did you eventually figure it out? Motors twitched or stopped? I have not noticed any of that. Were you able to solve that using logs somehow? Was the problem random or repeatable?

        I don't get it as it flies nicely on the second try. It has always been the first flight that causes problems. I took the gimbal off and will test again today.

  • I found some smaller issues with RC10:

    • RC deadzone settings don´t work for the serial RC control channels of the storm32 gimbal (RC6).
    • Sonar height differs after some flight time out of sonar range to the est. height. That leads to jumpy alt behavior commng back to sonar range.

    There is another autotune log in the folder.Maybe someone could give me a hint how to get lower PI values from autotune? Maybe it is possible to lower the autotune_aggr below 0,05?

    It´s a large Tarot T960 with 18" CF and 5010 pancake motors. The auw is about 6.x kg.



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    • Developer

      Hi Gregmaan,

      0.05 is the lowest it goes. What exactly is your problem with the tune?

      • Hi Leonardt,

        my problem is still that the copter still reacts too much in windy conditions.

        With aggr of 0.06 the problem gets worse.

        This happens either in stab and loiter/pos_hold.

        This is an old case. Last time with lower RCs you told me that I should reduce some filters from 20 to 10 Hz (because of high frequency vibs at about 20 Hz.)

        But with RC10 and above this does not give the results as before.

        Maybe you can give me a hint? Does I still have the vibs at 20Hz? How can I visualize these vibs?

        Thanks a lot, and sorry for my poor english ;-(


        • Developer

          Hi Gregmaan,

          What do you mean by reacts too much?

          • Hi Leonardt,

            maybe overshooting is the right word for what I think it does? Or in other words maybe too sensitive to outer influence?

            • Developer

              Hi Gregmaan,

              Sorry but you will really need to go into detail if you want me to understand what you are seeing.

  • Randy or Leonard,

    What are the preferred settings for logging in 3.3-rc10 with a PH?

    And what can be done to get auto analysis to work with this build?

This reply was deleted.