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
+1
in my opinion, guys, not having reliable landing detection is a big problem for experienced and early adopters alike. Designing and building up craft for professional/research use and passing these large fliers onto pros is a big responsibility. Having to worry about them flying in Loiter (which will be a common practice for survey/imaging pros), then landing and having the rig flip on its side as they try to disarm, destroying expensive props at best and causing bodily or physical damage at worst, is enough to keep a guy awake at night.
Can we do better than "just switch to Stabilize"? My intention is to be constructive, here, and as an engineer, I'm happy to dive into code to help try out some potential patches.
Because for me, I can't reasonably write in a technical manual that they must get to Stabilize before landing to prevent a failure of landing detection for multiple reasons. First and foremost, we can't assume throttle parity. they might have throttle quite low in Loiter to allow for descent, so the same position might correlate to practically no thrust and we crash to the ground, or the opposite with higher throttle, and we have a perceived flyaway. Secondarily, giving a pro with enough to worry about as it is on the job shouldn't have to concern themselves with always flipping to an essentially manual flight mode just to get the craft on the ground and review imagery.
I've personally had at least two occurrences like this, one on a big hex spinning 16" props (running 3.2.1) that scared the daylights out of me and just a few days ago on a small Y6 (on 3.3 rc10). So it doesn't seem to discriminate for frame size or AUW. For me one of the triggers seems to be adjusting position while close to ground before landing, which is very common in even moderate wind to make sure you have a nice balanced landing, especially when you need to land on a particular spot due to topographical variation.
So - I'm looking for guidance from developers and community alike. How can we all work together to do better?
Hi CrayFellow,
Do you have logs?
Here you go: attempt to land in Loiter then switch quickly to Stabilize while on the ground holding it by the landing gear
2015-09-04 10-49-04.bin
Hi Crayfellow,
The reason your copter isn't landing is because the vibrations go through the roof when you touch down. This makes the copter think that it is moving around too much to be on the ground.
Could you post a couple of photos of your copter to help us understand why this is happening?
I would say best method is not to trust auto detection but put motor kill function on a switch and manually kill motors just as vehicle touches the ground. it is the only reliable method currently possible.
I hope may be in 3.4 if GPS signal analysis will be improved it may prevent constant vehicle repositioning as it is what happens when it gets closer to the ground and it tries to hop from one spot to another as gps starts giving wrong coordinates and it tries to readjust.
Larger vehicle in my opinion requires to have lidar by default so it would always be aware of its factual distance from the ground, so it is also partially a matter of a design.
Other simple good method is to turn on geofence in parameters as it will make sure vehicle will not arm until it hooks more of less properly into the GPS system.
Still, from a customer education perspective first thing to teach now is to show them how and when to use motor kill switch to prevent damage.
if you do have LIDAR/range finder, is it taken into account in the landing logic? I haven't reviewed the code so I can't say personally. If you are saying it should be a requirement for larger craft, I am assuming you use it and have found it to be taken into account, correct?
I had to stop mine with a stick the other day. I was practicing flying close to trees at the edge of a little glen, when I hit some leaves and then landed in a patch of weeds. To my amazement, I did not crash!
However, the motors just kept going at just high enough speed that only some entangled foliage was holding the quadcopter down, and nothing I could do with my radio was changing that. (This is on 3.2, btw, not 3.3).
I looked around for a stick and used that to push the safety switch, which turned off the motors. Why do I occasionally get these issues with shutting off the motors from the radio?
did you try jumping to Stabilize? If you had, and you had the throttle stick at minimum, the motors definitely should not be spinning.
-
198
-
199
-
200
-
201
-
202
of 558 Next