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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    • Mine's not qav, but I can share my similar 250 quad values.. 
      2000kv 2206 motors, 6" props, ~510grams, and I noticed the battery was a little loose and wiggled around while doing the tune..

      In my experience, on a calm day, where I don't have to reposition the quad much, it'll tune in about 6 minutes per axis.  In the wind, it's anyone's guess. 

      Actually, I have to retune, depending on which prop profile I use, but at worst, it's just twitchy, so I think you should be able to use these as a starting point..

      Edited to say, if you haven't seen it, read this blog post, and follow his instructions under "basic setup", before trying to autotune.  Especially the filter values.


      • In the end I didn't use these because they were very different to other settings I'd seen and my starting point. That said, what I finally ended up with wasn't a million miles from here - so sorry for not picking up on this!

      • That's what I meant by so many things are buried. I'm definitely bookmarking that link. Thanks!!

  • Observations and a question from today's test flights:

    Three batteries used on my AD1 deadcat running Tiger MT4006 740kv with balanced 10x4.5 props.


    I run a CSG large M8N along with the Lea-6.  Per an earlier suggestion I switched my GPS_GNSS_Mode to 3 knocking out Glonass.  I reduced my Sat count down from the high teens to a best of 8 today, with HDOP around 1.5 and lower.  In PosHold there was less drifting about than with Glonass active.  It was reassuring seeing the higher Sat count but the reduced drifting about seems to prove a point.  I had set the GPS_MIN_ELEV to 20 degrees, will try 10 next time out.  Just once I noticed a sideways jump of about two feet just after taking off in PosHold.

    RTL, Land, Stab, AltHold, PosHold, seemed fine. Need to play with PosHold braking a little more.  Flew a short WP mission created in Tower with no problems.

    Drift mode flew very well and I would like to use it more for AP work.  The one issue I have with it is that the braking is very abrupt, with an immediate pitch up of about 30 degrees or move when letting go of the right stick.

    Is there a parameter that adjusts braking in Drift Mode?

    Flew well in most respects.  I thought I had done an autotune but on review the values almost seem to be defaults?  Will try again and see if I get similar results.

  • Can anyone tell me if the ESC calibration feedback has changed? I do not get the tone sequence in the wiki and I get a different tone sequence between 3.2.1 and 3.3rc11.

    Currently I get this (3.3rc11):

    - Throttle at max, plug in lipo and I get the usual boot tones followed some time later by a single short high tone.

    - Unplug, replug I get the boot tones followed by a long low tone and a single short high tone

    - Press the safety switch and I get a rising 3-note followed by a single short high tone

    - Throttle to low and I get the ba-ba bee arming tone

    Motors are then armed and respond to throttle.

    I am on a 3s at no point do I get 3 repeated tones for 3s.

    These are rctimer opto escs. Board is auav X2

  • Auto tune testing from today.  Thought the developers may be interested in larger units that works perfect on 3.21 and see how it autotunes with 3.3rc11.  I did three seperate tunes back to back with pretty much no wind.  Specs on copter:

    960mm X8

    5010 288kv motors

    18" propellers

    No clipping or high vibrations.  So basically pretty awesome with default params.  So how consistant were they?  Well the first two were pretty close and within what I'd expect from this size of copter.  That last tune was not so good.  All flyable, but I wouldn't use the last tune as the pid values were extremely low.

    Tune 1 log file:

    Tune 2 log file:

    Tune 3 log file:

    BTW aggrs was set to .075.  Maybe I'll try a range between .05 and .1 to see if I get any more consistency.

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    • Leonard,

      Which values should I plot to find out my rotation rate noise ?

      I'm looking forward to tune auto tune so I can get results where my hex don't overshoot .
      • Developer

        Hi Fernando,

        There is no output measuring Rate noise.

        There are some small changes in the filtering so hopefully Autotune will sort you out!!

        You probably just need to reduce the ATC_ACCEL_ roll and pitch numbers a little.

        • Thanks. I'll try that. I'm flying with rate_r and rate_i decreased by 10% and the problem seems to have gone. I'll keep them like that and also will decrease by 10% the ATC_ACCELL values.

          I'll test and revert. Looking forward to test the autotune changes.

    • 3702593976?profile=original3702593695?profile=original3702593985?profile=original

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