I just pushed Arducopter 2.2 to the Mission planner. This version went through extensive testing by a brave group of flyers and with both HIL and SIL testing.
See this link for more:
If you run into any problems please let me know here. If you find a reproducible bug, please add it to the issues list.
If you run into Loiter issues, try adjusting LOITER_P. It's 2.0 right now which may or may not be to aggressive for your copter. Nav is no longer used in Loiter control, which should make tuning easier.
If you run into a circling issue, try lowering LOITER_I to 0 and see if it goes away. If not, check your compass declination. A negative error will produce CCW rotations, a positive error CW.
If you have issues with alt hold, try lowering your THROTTLE_P, it may be too high for higher thrust copters.
If you have wobbles and can't seem to get rid of them, there is a new term called STAB_D, which is a derivative term used to tune out the wobbles. You can increase it until they stop, but just like driving a cadillac, you loose some performance and handling. In the CLI "tune 16" in setup will let you control this in flight, and "tune" in test menu will let you see the value printed out interactively before flight. See the wiki for more detail.
Many testers gave me a thumbs up on the code, so if you have an issues please post the flash log from the copter. The tLog isn't that much help to me for debugging as it doesn't capture the needed values at high enough rates.
(Remember, if you'd rather pull the code from the repository and load it with Arduino, you must use the "relaxpatch" version of Arduino in our downloads section.)
I believe I found the simple mode error. It was a bug that was working OK until Tridge fixed it so it was declared properly. Then the bug became active. I made the Simple mode function internal variables static and this should fix it hopefully.
I updated alt hold to not use dampener for now until we get more testing. Some folks saw a latency induced oscillation which was pumped up by the D term.
I added the automatic throttle cruise or hold value as a compile time option for testers. This basically looks at your throttle and climb rate while in stabilize or acro and determines your optimal hover value. This means you can enter any autopilot mode and not have to worry about your throttle position. It should make alt hold more reliable if it works. This is off by default until we get good field tests back.
Update pushed to GIT.
Just some refinements. I added JLN's throttle curve mod for landing. Hopefully that's correctly implemented.
Made the landing delay from RTL user settable
removed the ADC gyro filter, I was doing a lot of testing and determined it wasn't worth it.
Enabled the auto-throttle control by default. Please test in the sim
Altitude no longer resets when flying in Loiter mode
Pitch and roll dampening is smoother now. try values up to .08 for very dampened flight.
Mavlink can now trigger auto-land
I'll push a hex when I hear some good news from HIL testers.
OK, 2.2b6 is on GIT. The Mission planner is going to be out of sync until the release code. until then you can use the APM_Config.h or the parameters list in the Mission planner.
STAB_D : This is the gyro accretion dampener. This can remove small wobbles during sharp changes in angle commands. Making this too high can have a negative effect in performance and add a memory effect that can cause temporary loss in control. The in flight tuning is ranged so you are just below that effect.
If you haven't noticed before the control loops are in two stages. The first is a PI stage that converts some sort of position or angle error into a desired rate. These generally do not need to be tuned. They are more of a user preference on how fast you want the copter to perform a motion.
The second stage is the actual PID loop that needs to be tuned for the copter. This converts the desired rate into a motor command of some sort. I added a D term based on Igor's recommendation to the PI's for each rate controller. These should show up soon in the mission planner for the release. I cannot give you a concrete answer for how to tune the D terms, because they each depend on their function such as alt hold or loiter, etc.
Still, the absolute most important term is always the Rate_P term for each loop. Start tuning here.
The default PIDs are in the what flies great for a stock jDrones/3DR Quad with the purple motors in X mode.
I'm flying X frame.
Flew v2.2 this weekend and must say a very good impression.
Still need some PID tuning though.
What I noticed with loiter is that there is an increasing overshoot from left to right and finally turning in an oval shape circling.
One thing I also noticed is that the motors are clicking very often now compared to previous version. This started allready with the 2.1.x versions.
mmh thank you.
do you mean this "#define ACCEL_ALT_HOLD 0"?? because that is default
// to enable, set to 1
// to disable, set to 0
#define AUTO_THROTTLE_HOLD 1
Excuse the delay, I was on a date last night - see geeks do get the girls ;)
The PID's i started with are those that BIll posted a few days ago, i've actually taken my Stabilise p and r upto 3.4 now for a bit more locked in feel, this seems to be a good starting point - less edgy than the defaults.
As soon as my batts are charged I'm gonna go fiddle with in-field Loiter settings a bit - see if i can help with this over shoot and swirling issue. As i mentioned my first loiter attempt on satdy did this but then i fiddled and it stopped, i'll see if i can make some conclusions - or at least gather some data for those for those more able :)
Bah! Charged all batts, apart from the transmitter that died half way thru first flight battery... will try again tomorrow. Did convert a couple of dog walkers though, and one of them is a programmer :)
I found that loiter is still pretty good, stays within 2-3 meters with no wind but still has a bit of circular overcompensation, i'll see if i can get rid of this with some adjusted PIDS.
I tried the grab one leg and pull it away trick from the loiter position which it angrily resisted the full 20 or so metres i walked, then went straight back to loiter over my coke can marker. I'd have walked further had my tranny not started to die on me.
The multiplexing is now done in software by the 32u2, which is a stand-alone chip. So even if you have a crash of the main processor, the secondary processor will allow you to regain control. This allows us to support copters and planes equally well.
I should have an indoor flight done by the end of the week. Hopefully I can get some logs together that show the issue I have where the copter evens out over time even with stick (pitch) applied.
Take Video if you can at all. Indoors is a great control environment.
I Adam, I believe Jason has identified the problem, something to do with DCM. I've posted my flight logs from where I noticed it, but if you can have a log with that too, the better. (page 11 from this thread)
Sounds good. If its solved before I get out there and fly I will just validate the fix. Thanks!