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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      • Thank's Randy, I wait too to test the rc1

        • That explain why I have the issue only some times, specially in first fligths and no always.

          During first test I take off in stab, try to hover and switch to pos or alt hold, there the copter loose altitude that correct with quick raising throttle not to crash. Normally what I do is to take off in stab but switch to pos-alt hold when the copter is still climbing and there I don't have problem, then I land in pos hold and switch to stab again; it's sounds logic?

          Thank's Piers to post your issue.

          • that is SO the opposite of what I do and always have done. I "never" take off or land in any flight mode except Stab. EVER. Unless I am running a mission or set it to RTL.

            I "always" take off in stab and then if I want to set it to alt-hold or loiter I get it up to where I want and then flip to the flight modes. I also never "fly" in loiter as that is not what that flight mode was designed for. I just find no fun in fly by switch. If I wanted that I'd probably just buy a phantom or some DJI gear. 

            What I have found is you need to pay very close attention to where your throttle stick is at when you hover in stab mode and then go to mission planner and make sure your mid throttle is set as close to that as possible. Config/Tuning/Basic Tuning/Throttle hover.

            If your manual hover is blow 50% stick [over powered] and you do not set this value to your actual stick value then when you are zooming and flip to another flight mode with your stick way above 50% and then switch to back to say stab it will drop like a rock.

            Same goes the other way around, if you are under powered with your stab hover stick above 50% it will tend to zoom in the air when you flip back out of say loiter.

            Most of my birds are well over powered so I have to make sure my throttle hover is set to around 400 [depending on which bird I am flying] and I never have unexpected dives or zooms in the air :)

            • Craig: that depends the use and conditions were you flight, I fly in pos hold monitoring crops in FPV and taking photos, perhaps a Phantom can do it too but I like to diy my drone and get busy the second day with a phantom GLUP!!

            • I always take off in alt hold so there can be no surprises. It is what it is already and your aware of how the copter holds altitude with the baro and stick position. If adjustments need to be made this is the case regardless of what mode you take off in. But at least taking of in alt hold reduces the risk of a surprise altitude change. 

              If it's windy I fly in pos hold as I am still flying it yet it has the added safety feature of 'sticking' to where I put it. The devs have done a fantastic job fine tuning this mode I see no reason not to take advantage of it provided one is already familiar with the reliability of their gps etc, I think Dji had the upper hand in flight characteristics until copter 3.2 and the addition of pos hold,,,  after that it's never even been close. 

              • I second the alt hold for takeoff and landing.  Always used stabilize until I started autotune and later versions of arducopter.  Guess my manual tunes were always a bit soft.  Now it's pretty easy to bounce on landing with the really big rigs, especially on pavement.  Never loiter though, no need for an unscheduled haircut.

        • Ah right, ok thanks Randy, that's restored my faith in myself and everything else!  At least it's explained.

          Yes I had taken off, landed in Loiter, throttled down (still in Loiter), fixed camera, switched to Stabilize for takeoff again, took off in Stabilize,  and of course when I then switched to Loiter for the second time the above is what happened.  I think it throttled up again a bit just in time before the craft hit the ground, so no apparent damage done luckily.  The copter just fell over on it's side rather awkwardly, as I throttled up myself on the stick to save it.

          Will await the update. Many thanks for the swift diagnosis.

    • That's occurs to me too and reports, Is something that change in params from 3.2.1, if you have the throttle higher, don't occurs, now I change dead zone to 80 and raise a little mid throttle and not notice anymore but I didn't have enougth time to try to reproduce better the moment when occurs, next fly I'm going to try it more times.

  • Well Hello everyone, nice to be back in this old familiar forum! Sorry for the Intrusion, just wanted to say hi to all the people that taught me something about flight controllers and piloting during my APM 2.6 days. After a Tragic and Horrible Decision to try out XAircraft MINIX, i am now back to what works, Pixhawk 2 and Solo. 

    Just a Quick question if you guys dont mind (because most people who have a Solo or New pixhawk dont really remember APM 2.6) What happened to the parameter that turned your aircraft Tail IN when Landing from an RTH? i know the WP_YAW_BEHAVIOR for pointing home, but cant find the the Tail in Land parameter. if i am in the wrong place, please be kind to a weary pilot who  hit his own RTH button only to land here, please point me in tot he direction of Tower/Solo questions

    nice to be back i have missed you maniacs and brainiacs! 



    • Re-Welcome Thor, congrats for your Solo, perhaps you can find much more complete the instructions now if any one give you the answer   I'm only use the param that you mention, please share if you find what you say.

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