Note: just as the release was going out an issue was found re support for the all Camera Gimbals on the APM1s (it doesn't work) and with 3 axis gimbals on the APM2 (2-axis works ok but not 3). If you're one of these people, please wait for 2.7.3 which will be out shortly.
UPDATE: 2.7.3 is now in the Mission Planner
Functional Improvements over 2.7.1:
As per usual PIDs are optimised for the 3DR/Jdrones quad with 850 motors and 10" props. If you're using more powerful motors/props and are seeing bad flight behaviour in stabilize, start by turning down Rate Roll P in 25% steps.
There is still some question on whether the default Roll/Pitch Rate P (0.175) is high enough (it was 0.185 in 2.7.1) and also some people feel the Throttle Rate should be higher (currently 0.300 but some say 0.330 or even much higher would be better).
Please feel free to report issues you find in the discussion below and/or add them to the issues list.
Thanks and enjoy!
Hi Dave, there's "zeta" version now, with new Acro mode by Leonard (fantastic).
Keep attention with latest GIT: "Incremented eeprom format version to force users to accept the new defaults. Particularly important is the roll-pitch I term move from the stabilize to rate controllers".
If you save and reload your parameters after the firmware upgrade some goes wrong, like "AXIS_ENABLE 0" (now the default is "1").
Save you PIDs, upgrade the firmware and then reconfigure all the PID manually, don't load the old parameters set.
Haha Brilliant!! Thanks for the info Marco, I will bug test as much as the weather allows.
Funnily I have ALWAYS previously ended up removing any I term from stab and used I in the rate controllers, So this new implementation, at the very least, will save me a few clicks.
Also can't wait to try the new acro mode - prepare for an arducopter FPV backflip video :D
Good work team :D
Changing from Mediatek to Ublox has solve my problem with twitches. Rock solid now.
As Stephen mentioned, going from HDOP of 1.2 to 0.8 from seeing just one more satellite doesn't match my experience. Though I suppose with a really good sat geometry it is possible...
For instance, with the 12 sats I almost always get, I am getting an HDOP in the very low 0.7s consistently. But with 11 sats, I vary from 0.75-0.83, and with 10 sats from 0.80-0.91. With 9 sats, and I have very little data for this one, HDOP is barely under 1.0. [All indoors numbers, I had no outdoor "test gear" at the time.] I think you can see what I mean...
I took my data over quite a long time frame, ~2 weeks, as I tried different GP sizes and placement. However, I knew that HDOP of less than 1.0 was very possible so I didn't even record experiments or data that gave results >1.0 as I knew it was lousy, so no need to know it for future reference...meaning I have limited recollection of my lousy ideas to avoid to offer for guidance.
Of course my data is all relative, for my location and quad setup. You shouldn't expect to see exactly the same, but I'd expect you'd see similar relative improvement. Anyway, you can see the groundplane does help, and you should experiment with your arrangement. For instance, I added my GPS battery on the board below the GP so I could get the GPS module close to the GP. So I don't know what diff the battery module might make in between there, a different physical arrangement of GPS and GP (than mine) for you might work much better.
The weather here has not cooperated with my schedule lately. I have not even had a chance to use my new laptop in the field to see what the outdoors HDOP is, but I'm guessing mid-0.6s. BTW, from what I can find out, the Mediatek GPS module can only report on up to 15 sats, so that explains why I'm always pegged at 15 in my flight logs. I am interested to find out if more than 15 sats improves HDOP even if the Mediatek can't report on the extras. Also,I wonder if it "keeps" the best 15 sats or the first 15 sats for reporting.
Yeah, i discussed with Randy on the new default for the I-Term.
Ehm, the new Acro with "Axis Enable" i think it doesn't support flip with the default parameters... try! :-)
If you need more info read the "tester list".
Ok i will :)
I've just been out with the latest zeta...
3dr, 8X, 850 drones kit all round, 10.45 EPP, T/B ratio 1.0 (for now), 4s 3000 mah, Ublox external, xbee2.4.
Loaded up zeta, did hand test, backed off stab_p to 3.8 (this is a monster this thing) rest of params default
Quick hover and auto level in the lounge, this thing usually scares me in the lounge - not today!
Out to garden, (very calm night) quick stab test - 'oh my god, that's really good', the beast seems a lot more controlled!
Alt-hold baro only - 'spot on'
Loiter - didn't move, it just sat there, just a little bit of up and down with the breeze, an easy tune i think.
It just sat there, so i got my iphone out of my pocket
As soon as the phone focused i noticed that one of my lower props was not really spinning, just twitching about and occasionally spinning slowly.
Until that point I had not even noticed!!!
No twitches, solid loiter (not tested in wind yet), smooth power delivery, and ability to demonstrate beautifully why i have an X8, it flew perfectly with a motor out :D
Good work fellas, all the batts are charged and I'm in the field as soon as its light again.
EDIT: and i still didn't try acro... might have to get the night lights wired up...
I'm have question about DMP in source code.
#define DMP_ENABLED ENABLED and #define SECONDARY_DMP_ENABLED ENABLED , What're have effect and what're can couple define in program?
By un-commenting those two lines, you can enable the DMP solution from the MPU 6000 to be acquired in parallel with the DCM solution and write both results to the log file for comparison. We are using this to evaluate the relative performance of the two methods. Your analysis and feedback would be appreciated. Thanks.
thanks for your reply
I noticed that 2.7.4 will solve the 'climb on yaw' problem. Today I noticed during the first flight of my Octo (2.7.3) an actual, 'yaw on descend problem'. Is that likely to be solved too?
Need a little bit of help. My converted OctaQuad to Octo (by the way, giving me 18 minutes of flight time instead of 11 minutes with the SAME hardware (5% heavier due to 4 more arms)) has the problem that it starts to flyi (expanding) circles during LOITER. It will remain perfectly still in STAB mode. Using uBlox GPS with 10-11 sats and a HDOP of just under 2 (not sure why it is not better). It should be rock solid and Mission Planner shows it circling track. The GPS location is dead on, it just starts to fly circles.... Mission Planner indicates 'Loiter' not 'Circle' (in case you might ask).
It gets loaded/saved to the TRIM_THROTTLE parameter so it's saved/restored between flights.
This parameter gets adjusted automatically in about 10~15 seconds of hovering. It doesn't get used at all in stabilize mode...so basically, before you engage alt hold or an auto mission fly in stabilize mode and do a gentle hover for 10~15 seconds and all should be fine.