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!
Replies
This is very interesting. We do use the 3 axis 32 bit Alexmos controller. on the Pixhawk, which serial port is the one driving the Alexmos board?
nice! :) thanks for the info. Currently I have alexmos board on my gimbal, with pins for RC in for pitch, roll, yaw and CMD which can be directly connected to a receiver. But I opted to connect them on the RC10 and RC11 outputs of pixhawk then configured the stabilization on the Gimbal page in the Mission Planner. I still cannot see the difference between my existing setup and the new feature that supports alexmos gimbal cotroller. Maybe I will find out later. One thing I look forward to is the new feature to adjust the pitch to certain angles during misison flights :) this would definitely be good. I was pondering about that way back on the release of AC3.2.
to do what it says in 8 c I would imagine :)...to send demands to it.
Randy,
Will one of the releases allow remapping channels so that we can utilize different inputs for mode changes.
Thanks
Joe
Joe,
Rob Lefebvre is working on this and although it's not in this first release candidate I think it will make the final release.
Ok, Sounds good. I would like to have the ability to utilize my DJI DT7 transmitter for my arduphantom build. I want it my setup to look like a real phantom but better since it is utilizing a pixhawk.
thanks
Joe
Is it still possible to use DCM? I don't have much faith in EKF currently given the number of EKF_CHECK errors I still get on a fairly regular basis.
@Andy,
DCM is still there as a backup for attitude estimation (roll, pitch and yaw/heading) but for position estimation EKF is the only option now (i.e. inertial nav has been removed). The EKF is better at detecting and dealing with sensor failures (i.e. GPS & baro glitches, bad compass alignment) so it may be a real problem that the older system simply couldn't detect it. That's a guess of course, we'd need to see a dataflash log - Paul Riseborough (EKF expert) could have a look I think.
@Randy, so I now have working compass and things are much better, but they are not perfect - and I am not 100% convinced they are hardware related. If you look at the attached log everything is fine until about 23 minutes and then ErrYaw starts going steadily up and EKF and DCM get out of whack. If you look at the IMUs on the face of it it looks like vibration, but I don't think it is - if you zoom in you can see the underlying vibration but it actually looks like the copter is "twitching" - this is backed up by the MAG values which are "twitching" as well. I have seen this up close from time to time where the copter will steadily twitch back and forth (a bit like a micro autotune). Othertimes it just sits their stably. This is all 3.2.1 - so now will try 3.3 (when it stops raining) to see if that improves things, but what would cause this kind of behaviour?
2015-05-01 15-33-56.bin
Randy,
No doubt EKF is well suited for handling GPS and baro glitches.
However, regarding bad compass alignment, there is an extension to DCM that will handle compass misalignment just fine. Are you not using it?
I also note in some of your more recent posts that you are still "walking a tightrope" with regard to accuracy and speed of initialization of EKF. It will be interesting to me to see how that compromise works out for you.
Best regards,
Bill
-
445
-
446
-
447
-
448
-
449
of 449 Next