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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        • Developer

          The magic combination is Ctrl-Q from the MP's install firmware screen.  Just be careful though because we're going to push in the motors library changes in a couple of days and master could be unstable for a bit.  .. basically I'm just saying it's use at your own risk.

          We're going to be setting up a donate button on in the near-ish future.

          Thanks very much for the vote of confidence!  I wouldn't blame ChrisA and 3DR too much, both have been a huge help to Ardupilot up until now.  Things change, we just need to move on.

          • I would be more than happy to donate $100 from time to time. Also now that 3DR is not supporting the developer as much, is it possible to also open a DIYDrones hardware store and the proceeds of the profits of sales can contribute to the further development?

          • i am gonna hop on the band wagon and scream "TAKE MY MONEY PLEASE!!" as far as donations go. i hope something can be set up in the next few months!

          • I totally agree on a "donate" button for us users. Randy and team you guys are doing an awesome job with Ardupilot!

            On the other hand for me it's understandable that 3DR cut funding- the vast majority of Arducopter clients are using cheap China clones. Those manufacturers were building their business on 3DRs money w/o contributing to the software.
            • the solution is to setup a store to help fund further development. If we have good hardware supply built at competitive prices, then why would anyone want to bother to buy a slightly cheaper clone?  Time permitting, I would certainly be willing to help with sourcing hardware manufacturing here in SE Asia to help supply hardware to the diydones online store.  People to often think China is the only place that can do low cost manufacturing but that is really changing a lot now with the cost in China going up a lot. Electronics manufacturing in Malaysia, Singapore and Thailand can easily compete against these Chinese knock offs.

            • Count on our financial support! 

            • Two hands up for donation funding! There are thousands people using Ardupilot based platforms, so everybody can donate 5-10% of the hardware spent money, to get the software working and developing!

              Randy, can you please propose with your esteemed colleagues how to start the campaign?

              Some "stars" or so in the profiles will attract more people.

          • Hi Randy

            R. L. is now issuing videos flying with the SOLO 3DR drone. For me it looks like he is now low key with Helis or not at all.

            What kind of donation will be necessary to get a stable helicopter firmware upgrade after the still present  AC 3.2.1 version? I hope I am right, I have not checked MP for a week.

            I am supporting a donate button, absolutely.

            • Developer


              We released Copter-3.3.3 for the TradHeli in the last week or two.  I left Rob to make the announcement but perhaps he was preoccupied.  I worry about the Copter-3.4 release for TradHeli.  Tridge has been flying it but I know there's at least one (small-ish) issue to do with the PWM min/max values for channel 8's (i.e. the main motor) inputs and outputs need to be the same.  We allowed them to have different ranges in Copter-3.3 but we've taken a small step back in that regard.

          • I do not know what kind of discussion is going on.

            Anyway, this is just my idea that is practical for me.

            1) Single pre compiled download:             $0.99.-
            2) Annual membership for free download:  $12.-/year
            3) Pre installed OEM craft:                      $1.00.-
            4) Downloading source code:                   Free
            5) ArduPilot base flight controller:             $10.-/unit

            6) No idea for customized version for Linux

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