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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          • So I did some more testing at aggr .05 and .1.  Wow, what a difference.  At .05 the tuning was useless.  At .1 they approximated my best tune at .075.

            First tuning at .05


            Second tuning at .05


            Third time with AGGR set to .1


            And finally AGGR at .1 for the second time.


            I'll attach log files for these.  Is this helpful for beta test?  Or am I wasting space lol.

          • The log files are two posts up : )  I'm heading out right now to try different values of AGGR with multiple tunes.  Should be interesting.  Wonder in the AGGR setting is linked to the size of airframe on top of dealing with flexibility.  In this case, even though it's large it's also a very stiff frame.  I'll run the full set on this, then to the 960mm hex and finally test out the 1300mm X8.  Good thing I have a lot of batteries lol!

  • Hi,

    Tested position hold and auto modes on rc11 today. The ROI is still not working, loaded mission with MP This has been a problem with other AC3.3 RC's as well. After mission, switched to PH and landed, throttle down, and by mistake switched to Auto again, with throttle down left to dissarm it began to spin up again and ended on the side. Is this normal? Still a bit much altitude drop even at low speed. Otherwise nice performance. Thanks.

    • Also - I'm curious, what specifically do you find is not working about ROI?

      • Turned out that the problem with ROI is the Andropilot app for Android I was using. It erases the ROI point from the mission as soon as it is loaded by the app! Switching to Tower.  

    • Hi Arni, yes, I have had a 3 or more cases where the landing detection failed and yaw left killed some props. Bummer. For now the solution is to be very careful when landing... I find when I land steadily, I have no issue landing in GPS assist modes such as Loiter. 

      Also, the one time I had the presence of mind to "catch" it while it was flipping, I jumped to Stabilize and throttle at minimum was enough to minimize the damage (one prop that time).

      Long term solution as far as I know is tight integration with range finder sensors. Some also have a motor kill switch but I feel that is a safety issue as accidentally hitting that in the air would not be cool... switching to Stabilize at min throttle does effectively the same thing.

    • the log...

      2015-09-12 15-44-50.bin

  • I'm not sure this is a 3.3-rc11 issue but I just updated from 3.3-rc9 to 3.3-rc11 after changing my ESC's. When I arm the quad the motors do not start to slowly spin. I have recalibrated the TX, and the ESC's twice. I had to raise MOT_SPIN_ARMED up to 144 to get the motors to slowly spin upon arming. I went from ZTW w/SimonK to the Hobbywing Xrotor ESCs. I use these same HW xrotors on a hexa (w/different motors) running 3.2.1 that works fine with MOT_SPIN_ARMED set at 70.

    Has something changed with firmware that would cause this? Should I be worried about flying like this?

    • Just wanted to report that two more ESC calibrations solved the problem. Not sure if something now differs from what the wiki says but I just waited longer in between tones on last try and that did it. Set MOT_SPIN_ARMED at 70 and all is fine.

      • seems weird, Shawn. It would be interesting to have a report of ESC calibration available somewhere, maybe on the RC Calbration or Motor Test screen, to see what 'stuck'. What do you think it was that made the difference, just the wait (if so, maybe we need to enforce that in the code)?

This reply was deleted.


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