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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  • May be off topic, but I'd like to stress the issue of compass interference. I just recently re-assembled my new Alien 680 build by swapping out the KDE ESC's that I just could not get to work right with AC. In went the HW Quattro and it has zero issues. Go figure.

    So I'm going through the motions and EKF is yelling at me again. Looked at the graphs (love that feature) and there it was; compass into the orange. Drat. The mast is 6"+ from the top of the frame, the main power is underneath. Huh? I demag all steel screws. The rest are non-mag SS. 

    Then I noticed a live 12v JST connector for the gimbal poking out through a slit on the top frame. Hmm. Tucked it down inside the frame, EKF is happy, I'm happy.  Does that sound logical or just coincidence? Are compasses that sensitive?


    • I believe that to be coincidence. Even though it is a "live" wire it is not connected and carries no current so it also creates no magnetic interference.
      • I will try to recreate the compass interference warning. This wire is off the 12v step down regulator, and my understanding is when there is no return path for the current, an exposed wire can emit radiated EMI. No?

        • I will be interested to hear your results.  I can't see enough EMI from a low voltage open conductor to cause compass interference.

  • Hi! I did another test flight with my tbs discovery. I was a bit windy last day. but everything went fine. I raised my quad to 60m without problem, then raised it up to 100-120m and held it there for a few seconds then returned down and landed safely. I reviewed my logs after finding out a very surprising info. My current draw peaked to almost 60A

    my setup is this:

    sunnysky 900kv 2216

    gemfan 1045 carbon nylon mix

    DYS 30A V2 esc (blue)

    5200mah 10C multistar 4s

    normally I see my current draw below 30A. I was bothered after I found out about the current draw. Can somebody analyze my log? I will attach the file. thanks!

    2015-10-31 17-48-31.bin

    2015-10-31 17-48-31.log

    • Hi Randy,

      can you help me analyze my log?

      • altitude and current draw log. Are the spikes caused by glitch? my esc's are running fine after the flight
    • by the way, I have performed current calibration prior to this by doing this method:

      1.Fully charge your lipo

      2. Immediately fly your multi for at least five minutes 
      3. Land and disconnect the lipo from the multi
      4. Immediately, charge your lipo unti full using a smart charger with display (capable of displaying total current used for charging the lipo to full capacity).
      5. Connect your FC to mission planner using usb cable and open the Battery monitor sub-tab in Initial Setup>>Optional Hardware tab
      6. Look at the Amperes per Volt value
      7. Go to Flight Data tab and download data flash logs 
      8. Review the log file and check the CurrTotal
      9. Calibrate the current sensor by adjusting the Amp per volt to actual values. Do the math:

      New Amp per Volt = Amp per volt * Total Charge / CurrTotal

      10. Type the new Amp per Volt value on the box provided in mission planner for the calibration.

  • Hello! I would like to share with you the altitude controller's amazing performance when powered with XL-EZ4 rangefinder.

    It is extraordinary how precisely it can control the altitude, even in extreme low height flight.

    Thanks Arducopter team!!!

    Frame: Tarot 680 Pro with 4.4Kg auw weight

    • I have been playing with the lidar lite and am very impressed with how well it makes my quad hold altitude. It make arducopter still more fun to use!

      I am really looking forward to fuller integration of range finders,(during auto missions)and the potential for obsticale avoidance by adding a second forward facing range finder. 3.4 maybe?

      Dreaming I know, but 10 years ago who have ever imagined civilians drone in the hands of hobbist running auto missions?

      Please Randy, and rest of the development team, tell us how we can help to move development forward!

      Thank you again!
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