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

                  Paul, yes, I think it's the ESC or some other power related issue on the vehicle.  There are many things that could cause a spike on the pwm signal pin .. for example, are the ground wires from the ESC connected to the pixhawk's top rail (on the back of the pixhawk)?  The issue is very unlikely to be in the ArduPilot software.

                  • "for example, are the ground wires from the ESC connected to the pixhawk's top rail"

                    Randy, I have all the esc GND wires at the top of the Pixhawk and the signal wires at the bottom.

                    I sense that you have more options for this problem.

                    Can you please suggest some more possibilities?

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  • Didnt find correct place to post log related to 3.4-rc1 

    I am having serious issues with my copter, in the way that it does fly for a short period and then just descends abruptly hitting the ground. As soon as I see it descending (usually i'm flying at 2~3m above ground because I'm trying to find the cause of this problem) I switch to stabilize and cut throttle to avoid major damage. 

    At first I thought this is was a temperature related issue, but now I dont think so.

    I saw a log that contained barometer error in the exact moment the temperature rised to 70º degree inside the frame (it's an waterproof one) but now logs dont even show any error, the copter just falls to the ground...

    Anyone willing to help me figure this out ?

    2016-05-30 15-01-15.bin

    2016-05-30 15-34-03.bin
  • Hi I was wondering if anyone could take a look at this log and help me out with a flyaway problem in loiter mode. Flies well in stabilize, but when I enter loiter, it changes roll to max within a second or so and flies into a tree unless I switch to stabilize. There are some vibrations but I don't think this caused it as my other two MR's are doing the same thing in loiter.

    copter 3.3.3

    6s, 380kv 15" props, 880mm 6lbs

    Could it be the momentary gps glitch? I wasn't able to run telemetry, but here's the .bin log of the last crash where I enter loiter once, and have to go back out immediately as it seemed to take off. Then I tried it once more and it took off into a tree before I could switch to stabilize. Luckily it escaped undamaged. It shows a radio loss as the antenna broke off when it hit the tree. Or could the issue be caused by these settings I had previously made in attached photo?

    Any assistance and I would be most appreciative, thanks!



    • Don't look a gps glich, only look a vibe glich the two times that you switched to Loiter but I don't know why, your compass and acc all are well calibrated?

This reply was deleted.


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