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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  • On 3.3 rc9 I tried a autotune, after a while the remote controller shifted 90 degress so pitch forward became left roll and so on... after half a minute or so it was OK again I experienced this twice during the autotune. So I finished the autotune. After landing and saving the autotune I took off again and after just 20 seconds it rolled to the left and fell to the ground with a broken arm. :-) Curious if someone can explain what happend during the autotune, it hard to fly when the remote suddenly get screwed?

    2015-08-21 14-27-21.7z

    • Developer


      So it looks like super simple mode is setup for the 2nd flight mode (AltHold).  Because AutoTune was triggered from ch8 (an auxiliary switch), it continued to use super-simple when the vehicle was in AutoTune.  Super simple has a 10m dead-zone around the pilot so when the vehicle crosses out of this deadzone the controls end up suddenly being rotated.  Basically for super simple it's best to keep the vehicle outside the 10m deadzone to avoid confusion.

      The final fall looks like a mechanical issue.  In particular it rolls left and back so probably motor #2.  Motor #2's output goes to full which is also consistent with this theory.


      • Thanks for analyzing the log!!

        I do not Think SSM (Super simple mode) was set, but I will double check it.

        Was suspecting that one of the ESC was failing, and that it was motor #2 is good to know. Looking at a video from the onboard camera I suspected one of the right motors since it looked like it lost trust in that side and tilted to that side  in the video before it hit the ground.

        We have great weather for flying in Sweden now, it is good that I have a couple of copters so that I can fly even when one of them is down for service!! :-)

        • My misstake with the SSM, I normally don't use it....

      • This rotation of controls efficiently renders this mode completely useless as it is too dangerous to use it. Why is it still happening? Is it possible to do something to prevent this rotation of controls?
        • But the whole purpose of super simple mode is to change the controls so they are orientated to the pilot.

          Personally I think super simple mode is a great addition and makes retrieving a quad when orientation is lost very simple without having to resort to RTL.

          • If that was the idea - to help - it does complete opposite in reality. It randomly and unpredictably inverts controls and they stay inverted forever no matter if you move drone out again. It would be way better to disable this feature as because of it this whole mode has to be turned off - it is unsafe.
            • To keep it "simple" (pun intended) I programmed a separate 3 position switch, on a Taranis, with Normal, Simple and Super Simple. Each have audible alerts. 

              SS was the only thing that saved my bird when an Auto Mission went awry. YMMV

              • I have it done same way but had to remove super simple position as, yes, it is nice when it works. if it could be reconfigured to flip controls within 1–2m from a launch point, then may be, but i had it flipped in 10m or so numerous times and usually could then turn it off but last time on rc5 when it flipped i made it go out, then it flipped again in other way making it impossible to control the vehicle, then i turned it off into normal mode seeing where nose was actually oriented and controls were still messed up rotated at some angle and inverted at same time, drone was going fast aiming into a house next to the field, so i had to drop throttle in the air and drop it down from 20ft. After that i removed this cursed super simple disaster and never going to use it again. I just do not trust it anymore.
                I asked here about this and current consensus, as i can understand is to use classic simple mode that is compass driven with no gps involved.
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