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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              • Yes, thanks for the tips!!

                As an old time RC heli pilot, I always take off with the tail pointed at me, it's an old habit that is hard to kill!

                • As an old time RC heli pilot, I always take off with the tail pointed at me, it's an old habit that is hard to kill!

                  As a not so old time pilot, I do this as well even though I started out on multirotors. I personally LOVE simple mode [no so much super simple]. When I started out it was on multiwii and I didn't even know about things like level [horizon], headfree [simple], or any other assist and it took me probably 2 months just to be able to not break a prop or arm per flight :( Then I leaned about hooking up the FC to the pc and enabling different flight modes and a whole new world opened to me. The pure fun part, not the oh god am I going to crash again part. 

                  My issue flying these things is when they get 50 or so feet out and up they kind of all just turn black to me and I can no longer "see" which way they are pointing. LEDs help a lot but even so when I get 200 or 300 feet then even the LEDS just kind of look white so I lose orientation a LOT. 

                  With simple mode that is not an issue to me as it no longer matters where the MR is facing. My controls are consistent and I can play around more actually flying it instead of worrying about crashing it :)

                  I also have it on a switch but I tend to enable it before take off so I know exactly which way my controls are at all times. I don't use it all the time but when I do I really am glad it is there.

                  • I would not even consider flying without one of these now. It is VERY bright and even during the day with sun you can see it a long way away. I put the red up front and set the mode to blinking so it hardly uses any juice. I crashed a few times from simple disorientation I've not had the problem since. FYI I don't really trust it to be a low voltage alarm as it gets lower than I like.

                • If you have that habit, be shure that simple mode is going to work for you, the other tip that I use is, if for any reason my copter flies behind me (rare) I not turn my body, only my head, as you are flying in simple mode you have to mantain your body in the same position than you take off, Good Luck.

            • I set up my friends TriCopter to use super simple mode.

              He has 3 flight modes on his only 3pos switch, Alt Hold, Pos Hold and Alt hold with Super Simple although I've renamed it Home Lock mode for him.

              Although he only has 3.2.1 on an apm2.6, it's worked flawlessly for months now. As long as you're aware of how it works (pitch and roll are relative to you and not the uav's orientation) and how to engage it I think it's a great addition to regain orientation without resorting to RTL.

              • Thanks for sharing this!

                I always thought the only place that simple / super simple modes would be confusing was if the operator was trying to use downlinked video from the aircraft. In this case it could be very confusing.

                Otherwise, I would imagine that it should be a help.

                But as others have said, if you are flying very close to yourself, and there was a GPS glitch, it could get confusing very fast. But I rarely fly that close to myself.

                If anyone else has any success (or fail) stories, please feel free to reply. Or perhaps a separate thread is appropriate?

                • I fly fpv too, that one of the reasons that I prefer in a switch, you change to normal mode and fly normaly.

        • Ok, you two are worrying me now! LOL

          SuperSimple mode says it works even if the bird goes behind you "The advantage over simple mode is that the controls are applied from the pilot’s point of view even when the copter flies behind the pilot/home location."

          But I see your point, if GPS glitches happen, then where 'home' is could be wrong!

          I'd like to hear from others as to how dangerous these modes are, but for now, I'll stop using them, just in case!

          • I have simple mode in a switch and used for two or three years without issues, I fly FPV and when return I switch to simple and land and no take care were the copter is pointing, I have as a safe switch too in case that I have to return with no fpv and no gps (redundancy safe), In combination with Poshold isn't a risk to crash if you confuse the switch, simply stop moving and solve it ;) (really are modes for vague pilots like me LOL, but works coooll)

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