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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  • what are some of you using for ANGLE_MAX? The default setting on mine is 3000 - so that would be 30 degrees, that seems a bit weak no?  the wiki says that 4500 is the default, but apparently that is not correct.

  • something odd-  i enabled motor spin on armed (MOT_SPIN_ARMED = 1), and it does not seem to be working properly. when I arm the quad the motors don't spin. I will take off, fly around, land, and the motors will stay spinning until it auto-disarms.

    with mot_spin_armed set to 1, I get that the motors will stay spinning after landing until the FC disarms - but - shouldn't the motors spin up as soon as I arm the FC with stick commands?  I have my THR_MIN set to 115 so it is enough to spin the motors, as evidenced by the motors remaining spinning when landed post-flight.

    I have BRD_SAFETYENABLE = 0 if that helps.

    • I have to move throttle a little to help them begin spinning, at land stay spinning like yours, Is like they have no enougth throttle force to move.

      • I think that's THR_MIN ??? I turn mine up so they spin when I first arm. 

        • nah THR_MIN only seems to govern what the props will spin at once under flight and dropping throttle.  when first arming the blades don't spin - apparently it requires setting motor spin on armed value to something that represents a percentage of throttle, enough to spin the props.  MP's descriptions are blank and there is no info at the wiki. 

          It would be really nice if any settings that govern motor spin are expressed in PWM values instead of throttle percentages. it is easy to figure out t what pwm values a motor will spin at, but using percentage of throttle is only a guess.

          • Yea come to think of it there is yet another setting for what the props do when armed right??... spin slowly can be selected right? But I do recall I had to bump some number up a bit to make them actually move. 

            Man your not lying on the throttle PWM instead of a percentage at least in 'plane' I had a heck of a time trying to figure out what to set cruise throttle with a gas engine because it would not do so on the ground for testing because it wont move the throttle until it see's it's moving for safety reason so I had to drive around with it in my truck to see how far it would open the throttle when I set it as a  percentage. That was 3 years prior though so might be different now. Talk about OT!!! ha sorry. 

            • yeh i just don't get it why a percentage method was used instead of concrete pwm values. using the radio calibration tab it is easy to see what pwm the motors spin at. Everything should always be referenced in pwm, JMHO.. 

    • I thought you have to set MOT_SPIN_ARMED =  70 for it to spin.

      • hrmm-  it seems you are right, I thought it wa a zero = off and one = on type of setting. 

        it requires some sort of non-documented value which represents percentage of throttle?  I found posts all over the internet ranging from 70 to 800 with no clear answer.  Mission Planner description field for the setting is blank. wiki page has no info on this setting or recommended values (that I could find).

        Logically thinking, I would assume that enabling motor spin on armed would use the THR_MIN value - or would that just make things too easy? ;p  Why would you need to independently set the motor spin on armed speed when you have already specified THR_MIN? makes no sense. 

      • Yup 70 is slow spin

This reply was deleted.


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