ArduCopter-3.2.1 Beta Testing

ArduCopter 3.2.1-rc2 (release candidate #2) has completed beta testing and has been released as the official version available through the mission planner and other ground stations.

Changes from AC3.2 are listed below and in the ReleaseNotes:
1) Enhancements:
    a) reduced twitch when passing Spline waypoints
    b) Faster disarm after landing in Auto, Land, RTL
    c) Pixhawk LED turns green before arming only after GPS HDOP falls below 2.3 (only in flight modes requiring GPS)
2) Safety Features:
    a) Add desired descent rate check to reduce chance of false-positive on landing check
    b) improved MPU6k health monitoring and re-configuration in case of in-flight failure
    c) Rally point distance check reduced to 300m (reduces chance of RTL to far away forgotten Rally point)
    d) auto-disarm if vehicle is landed for 15seconds even in Auto, Guided, RTL, Circle
    e) fence breach while vehicle is landed causes vehicle to disarm (previously did RTL)
3) Bug Fixes:
    a) Check flight mode even when arming from GCS (previously it was possible to arm in RTL mode if arming was initiated from GCS)
    b) Send vehicle target destination in RTL, Guided (allows GCS to show where vehicle is flying to in these modes)
    c) PosHold wind compensation fix
    d) prevent infinite loop with do-jump commands pointing at each other
    e) pixhawk memory corruption fix when connecting via USB
    f) vehicle stops at fence's alt limit in Loiter, AltHold, PosHold (as it did in AC3.1.5)
    g) protect against multiple arming messages from GCS causing gyro calibratoin failure

Thanks to Raph for the video.  This is actually a video from AC3.2 until we have one specific to AC3.2.1.

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                  • T3

                    Hi Craig,

                    I just came across your reply. What I found is that the M8N is indeed more sensitive. The positive thing is much more satellites and a lower PDOP/HDOP. The negative thing I found is interference with bluetooth. Hence, it depends on the specific setup if one should use or better not use the M8N. This is why I understand that you/3DR are not moving towards the M8N, because you have to make sure to sell parts that fit in almost any setup.

                    Anyway, I have a questions: why did ublox advised you not to move to the M8N? Only because of the possible interference or is there anything else?

                    I am asking because I never had any problems apart from the (minor) things mentioned in my latest blog post with any M8N in countless hours of flights - with different receivers, telemetry frequencies etc. Just the bluetooth problem. Hence, I am wondering if there is anything else to look at.



                  • Developer


                    I've replied over on you discussion just to say that I still believe the PM message is a red herring and based upon that discussion I've added a fix that will go out wit h AC3.3 to resolve it.

                  • I had some twitching issues a few weeks ago (last time in the air) with the CSGShop M8N installed and in poshold, but don't know if the GPS is the root cause. I do not feel confident flying the copter again until I understand those errors.

                    What I'd like to know is if the error reported by performing Auto Analysis is an actual problem or just a red herring. It is in every single AC3.2 log file I have, and in 3.2 logs that others have posted.

                    While the 3DR GPS worked well enough once locked, there were several days I didn't fly because the NSat and hdop simply refused to provide good enough numbers to fly (or glitched after takeoff), whereas the M8N works even on the cloudiest days.

                    Of course you are referring to the M8M, the more cost effective version IIRC.

                  • Interesting topic.  Thanks for the clarification!


                  • Yes I'm sure there are a lot more factors than I know about. I remember Tridge saying the velocity numbers were as, if not more, important than the exact location / accuracy. I wouldn't hesitate to use the stock 3DR again its a has very proven record. However the appearance and venerability of those 6pos and 4pos wires is one downside. I think I damaged the female connection on the gps or something in a minor conflict with a tree :] 

                    Thanks for the info... interesting.

                • Developer

                  Is it so cut-and-dry that the M8 is better?  I've heard it's more sensitive but also more prone to interference.

                  • With this one never had a problem: M8N and HMC5983 We have 4 of them.

                    Locks in twice as fast as LEA6H and hdop is so much better than the LEA6H that it is incredible.(GND and PWR) are run separately from the Tx Rx serial lines

                    Makes our Quads and Hexa rotors running 3.2.1 rc2 like on rails!

                    Each one is free to decide but when such huge differences exist, I think it is worth considering the few dollars more to be spent.


                  • No problems with my 6m/6H's either. I did have one that was taking forever to  acquire satellites. It ended up that the on-board battery was dead. Replaced it and works like a charm. These take around a minute, maybe a little over before the HDOP drops <2.0. Once i clear the trees, it usually holds around 1.2. I've yet to see it drift more than a meter horizontally in loiter, and that even under dense tree cover with power lines all around. I wonder if folks having issue with the 6's have them configured correctly (  ) or maybe have a dead battery?  

                  • I had a problem with the 3dr one. It took me a while to figure out that's what it was. The compass wasn't %100. It was a intermittent problem however in all honesty it could have been slightly tweaked in a hard landing because it used to work great!  But after I started having issues I decided to try the Neo7... that was darn good too. But so far the best performance has been the M8. The best thing is how fast your ready to go. 10 sats usually in the 1-2 minutes. 

                  • Haven't had a hiccup with my 6M/6H's

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