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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      • Thanks Luis- yeh i know it's not technically a failover gps, but it's also not a dual active gps- i guess it is more of a 'preferential gps' :D 

        Thanks for the catch on the param / version- yes sorry I meant SR2 and AC 3.3 - guess I was a bit over excited and typing too fast ;p

        the T1 value shows the non-preferred GPS sat count (Cn06) - the "active" gps is the M8N with 13 sats and 3D DGPS.  So I'm not sure why T1 would show the non-preferred gps sat count.

        Still not sure what T2 means.

        Thanks for the link- helpful info. Although the protocol selection is not correct for this application- i am using protocol 3 (frSky D Port) and the Teensy uses protocol 1, GCS Mavlink, and S-port Rx.   Additionally, of most importance, the above link is using OpenTX 2.1.x - Vastly different with telemetry than OpenTX 2.0.x - I just wanted to note that in case anyone else references this.

        baud is 9600, 8, n 1  for the FUL-1

  • lowly request on GPS config.  would it be possible to include a "no override" switch in the params list, preventing MP from auto-updating the GPS config settings? many of us like to shut off or adjust things not accessible in MP params, such as disable NMEA messages, etc.   This would save having to pull the rx wire on the gps unit.  of course if you fubar your gps settings you can clear the no override flag in params and on next boot MP will rewrite the proper config.

    • Developer


      I've heard of people pulling one of the wires from the GPS to stop the auto configuration but so far I haven't heard why that's being done.  If it's because you're piping the GPS's data to another source and that other source requires NMEA then that's a reasonable idea although I worry that the 38k serial link might run out of bandwidth to support both types of messages.

      • Hi Randy - Thanks for the reply. No it's more of being able to make slight advanced changes to the GPS config in U-Center and have them not get wiped out by the forced settings in PH.

        When I installed my M8N with PH and then later looked in u-center, NMEA messaging is enabled. I have to shut that off in u-center.

        Actually you and I discussed this briefly in another thread- you suggested I use Marco's specific M8N config- which I did - but it gets wiped out each time the PH reboots so the only way to save it is to yank the rx wire.


        sure it's easy enough to yank the rx wire but having 'gps config no override' as a parameter in APM would ultimately be a more elegant option, but I understand it's probably low hanging fruit from a dev perspective.

      • By removing the TX wire from the APM/Hawk [the RX on the GPS] the configuration is not updated on the GPS so when people make custom configurations on their GPS modules from say U-Center it is not overwritten by ArduPilot on bootup.

  • I've just had a problem with there being 4 more images than cam trigger events. (224 images, 240 trigger events) on RC11 during an auto mission. Previously I've only ever had more trigger events than images when the camera couldn't keep up, but it can easily keep up with the rate it was being triggered here.

    Does anyone know what could be going on?

    There's a log over on the thread about it.

    • I've just found some more weird behaviour with this log while using the geo ref tool. Using a time offset then generating the location kml, the flight path gets cut off about 40% of the way into the flight, then jumps to the end position, and also has a large gap in the image locations, however using the 'create kml + gpx' option in MP, the full flight path is displayed correctly. This makes me think there's something wrong going on with the geo-ref tool, or else my log is somehow seriously broken.

      There are images showing this on my other thread.

      Also my geo-ref tool doesn't give me any options to change the field numbers like it has in previous versions (and like in your screenshot Shaun).

      Edit: updated MP from 1.3.32 to (beta updates) and now I can use the time offset without it cutting the log off half way. Still has the non-matching number of trigger events to images though.

    • Thanks for looking Randy. Sorry it was 224 images, 220 trigger events... was a typo in the last post. The card is a fast sandisk ultra 8gb which benchmarks as having a good write speed. This log is only 10mb for a 15 minute flight and I don't have any additional logging turned on, so I'm pretty sure it's not an issue with the card not being able to keep up. If there's a way to tell for sure whether this is the issue though I would like to know.

      I just want to make sure I can avoid this happening in future since I'll lose precision if I can only use the offset geo ref method (not to mention the pain of trying to get the offset right) rather than being able to use the cam trigger events.

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