The latest AC2 code is posted. This is the last code before the big switchover to APM2 codebase.
What you should expect: More stability and better handling, especially if your CG is not centered.
Heres the update list from the downloads section:
Most stable flying version yet. Includes new stability patch by default and a new DCM gain and clamp value that should reduce drift due to linear acceleration in missions or long flights.
Switched rate gain calculation to use raw IMU rather than the DCM's omega. This crisps up the response a lot.
1280 has lost local flash logging, sorry, but it's just not supportable any longer.
some older tests have returned now the program memory is freed.
Remember, to use the new logging format on the 2560, you need to erase it at least once to format it.
He're the video showing just the control loop patch. The DCM patch was added later and improved the handling some more.
I tried out .55 yesterday and first with the stock PID settings on my stock 3DR frame. Only added wait is a light gopro payroll and I'm using 3S and 4S. Can't remember what I used in this. It was the first time I engaged Loiter and it took a lot to resist switching back to Stabilize. Really lurched around a lot and the wind was not that bad. Just a light breeze. I then set up my PID exactly like Jean-Louis posted earlier in this thread. It was the first time I changed from the default settings. His settings make the copter much smoother and wind seems to not effect it at all. It would be perfect for camera or fpv but not for any aggressive type of flying.
I haven't tested Loiter yet with these settings but will tonight. Loiter with the default PID was unusable.
BTW, I'm not using sonar.
Board is sitting inside soft styrofoam. It breaths well so I don't think it would effect the pressure sensor.
I just tested 2.0.55 on my 3DR frame and found it very tricky to fly. I thought it was much too sensitive. When I took a look at what I think the default gains were, I found the following. These seem significantly larger than those that Jean-Louis posted. Why would the default gains be set to such aggressive values? It seems that the defaults should be conservative and people would tweak to get extra performance from there.
The default PID's have always been like that for me but I got use to it and liked the responsiveness but then I tried jean-louis settings and it's definitely a smoother flight. Not great for zipping around but for soft flying and filming, it's perfect. Very easy up and down without the wobbles. Also .55 default PID is much better at descending. I need to enable ch6 tuning today and find the sweeeeeeet spot :)
Tested loiter with these settings and 4S 5000 nanotech and results were the same. Very aggressive over shooting just like previous video. Is this normal loiter performance or should I look for some interference? What settings should I look at in the log to see if I'm getting some wrong performance?
Weight with 4S5000 is 1732g
My GPS is attached to the underside of the top fiberglass plate on the 3DR frame but I have replaced the plate below it with a solid aluminum one to help isolate the GPS. I have the xbee900 up there with the GPS but disabled it in the last flight to see if it was interfering with the GPS but the results were the same. My mag is soldered on and I'm using the 1280 board if that matters.
Hello to All,
Here, below, my latest working PID setup that I have used successfully with the v2.0.55 + alt_hold patch, I hope this will help you for your tuning.
The tuning of the Throttle_rate is very important to get a smooth flight during the Alt_Hold.
Below the video of the last WE tests flights with the Arducopter v2.0.54 + stability patch:
I hope that the weather here will be less stormy next WE... I shall soon post more flights videos with the v2.0.55+ ASAP.
Good tuning with your arducopter and enjoy flying...
Over California there is a high pressure system with cold air and no winds. This makes a perfect test.
Hello Martin, your are lucky, I need to find urgently a teleporter to go to California for conducting my tests flights... ;-)
Good tuning and flights....
Grenoble, no wind, sunny mountain full of snow.... No need to go so far away. :-)
I tried 2.0.55 in my stock 3DR quad.
Loiter seems OK. There was some pulsing and log shows something on with alt. but it seems to stay in position at least as well as 2.0.49. 49 didn't do the pulsing.
I sent it off on a mission. It headed off to WP1 then flew on by to crash in a direct line through WP1 but well past it.
I haven't a good chance to look at the log, but I'll post in case it's useful. I only have a 1280 board in the quad, so there's only the tlog.
2.0.55. After 1-2 minutes of flight my quad begins to increasingly flip to one side and tend to crash. Feels like it opposes or even tends to return to location it's lost. Also the camera support leans to the opposite side as if IMU's internal horizon doesn't match the real horizon.
P.S. I have no compass, also changed no config due to basic X-config.
For the camera problem you can reverse the movement of the servo with a parameter in the APM Planner.