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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      • Randy- I agree, OF has been working very well. Check out my blog post about my experiences with it.There are still some bugs to get through, but it has been pretty exceptional so far!

    • I bought a PX4 optical low/sonar module more than a year ago and could not get it operational then. If it is at all strait forward I would love to make another go at it! just need to sort out some vibration issues first.

      The video show the quad holding position and altitude very well, great job!

  • Today I testet my LIDAR, connected via PWM. It works great in AltHold and PosHold.

    But in Auto mission the LIDAR is not working. I hat a Mission with descending to 2 Meter. The 2 Meters are barometric, If I put some thing under the copter there is no reaction from the Copter. I guess this is a bug.

    Also the RNGFND_OFFSET makes no changes even if i put in extreme values.

    • Developer


      Yes, I'm afraid that the Lidar is only curently used in manual modes (AltHold, Loiter, PosHold).  It's not used in AUTO.  That was the case with AC3.2.1 as well by the way.  Hopefully in AC3.4 we can get that working, it's not trivial though because we will want the user to be able to specify for each waypoint whether it's an altitude-above-home, altitude-above-terrain or an absolute altitude.

      • This would be a huge improvement for our company.  We've got a 1300 X8 for carrying lidar, but the lidar is limited to scanning no higher than 80m.  For our mountainous terrain and huge tree canopy, there's always a possibility of a tree collision.  The possibility of using the lidarlite (or scanning version) could save our large lidar from being damaged.  I was talking to the owner of Phoenix Lidar about integrating his AL3 into the autopilot.  The Velodyne 32 head scans 10 degrees forward and 30 back.  No reason is couldn't help with terrain info while it's scanning for topography.

        • Shaun: (sorry to the group for an off topic question) why lidar for topography when you can get high resolution 3D from photo images with SFM through software like Agisoft PhotoScan? perhaps a reply by email Thanks a lot. Fred

          • SFM is a great, inexpensive tool for bare earth.  Unfortunately rarely do we have bare earth.  Volumetrics at excavation sites and open pit mines are really your only customers.  Lidar penetrates vegetation with multiple returns (not all lidar though, some single return).  Density is also much more consistent, don't believe all the SFM coolaid lol.  Bad light = low to no density.  Now to make this on topic, any way to incorporate our 700000 points per second lidar data into arducopter 3.4 code for collision avoidance : ) 

            • Thanks a lot for your quick (!) response. Limited knowledge of lidar; I didn't realize it has that penetration...  700k/s: that would be quite a bit more data to process. : ) = ironic or happily wishful?

      • Oh, I understand. Of-course it is a very good idea to have different altitudes selectable for the mission, that makes it safe and easy to understand. So I will hope for 3.4

        But as Roberto asked, I guess in Guided-Mode it is easy to get it working as per default?

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