Version 2.5 of the ArduCopter code is now available in the AP Mission Planner and in the downloads area!
The default PIDs are optimized for a 3DR/Jdrones quad with 850 motors and 10" props. If you're using more powerful motors/props, start by turning down Rate Roll P in 25% steps.
While some testers have reported very good flights with the default PIDs, some have reported that this release is a little "sharper" due to the DCM improvements and have found they needed to:
reduce stabilize P by 10% (i.e. 4.5 -> 4.2)
reduce stabilize D by 30% (i.e. 0.15 -> 0.10)
increase rate D from 0 to 0.001
Tuning loiter can be tricky. Refer to the discussions which will appear below for more community feedback on what parameters work best.
Please post your feedback in this discussion. For enhancement requests and bug report, please add them to the arducopter issues list. When possible please include logs (tlog and/or dataflash) and tell us whether you're using APM1 or APM2 and what version of the software you're using (presumably 2.5 but tell us anyway!).
Thanks for this release go to the developers (both in the core team but also those who have provided bug fixes through the issues list) and also the community members who participated in the previous release thread and provided some great detailed information in the form of issue reports and logs which allowed us to nail some bugs!
Very inspiring to read all the positive feedback on this release - well earned recognition to the developers!
Now, before I start the tuning work, I would say that time has come for an official update on the Loiter tuning Wiki!
I just checked the current writing and it is not updated (actually misguiding and texts in two places: Flying and Tuning).
The new texts should sort out how the Hold and Loiter params work as per today and how to approach tuning them.
I am available to provide feedback on new text version.
Thanks / Tomas
Yes! + 1,000,000
If I can figure it out, I can write the wiki. Jason jotted something down on the devlist last week but I can't find it now. :(
I'll have a punt too. If i find anything useful I'll confer Robert.
In the meantime, set your quad up as you like it, pray for little to no wind, set loiter _p to 1.0, set nav to 3.0. (or copy marcos or balloons param files (modded to your frame and position of course)
Loiter in max 4*4m box, I'm getting 2*2 most of the time.
I've tried this on a small light quad, a big heavy quad and one 'Jacob' tri, with rate and stab PID's ranging from almost non-existent to 'ninja'.
I'm waiting for wind now, to fill in the blanks!
EDIT - I've got APM1 for info...
Dave, I have a particular problem because I'm flying a TradHeli, which actually does not sit "level" in the air to remain stationary, it actually has to be allowed to hang at whatever natural level it needs. So doing a "level" command on a perfectly flat floor does not work. When I do that, I have to hold some back and right stick to keep it in one place in Stab mode. Otherwise it flies off forward and left.
So when I engage Loiter, it also flies off forward and left maybe 100 feet before coming back.
My loiter tuning NEEDS to start with a good in-flight levelling, but I can't get Ch7 Auto_trim to work. I tried it, but it doesn't seem to have done anything. I'll try again maybe tonight.
Gah, IE just crashed and i lost a lengthy explanation.
In brief, you can try to compenstate for the lean by puttin card under the front left skid - level again, trail and error.
But much better than this... instead of holding 'arm' (throttle down, full right hand yaw) for 4 seconds, hold it for 15. You will see the red amber and green lights (ABC) on the apm begin to cycle. This is the Auto-trim feature, you now have about 30 seconds to hover your copter as still as possible while the APM adds in the 'learned' trim required to keep it level.
Land, disarm, arm normally and give it a try. If its not perfect do it again but from a different orientation.
This needs to be done in a windless environment ideally, preferably at the same temp as at your flying site.
Let me know if that helps on a trad heli, not tried it yet.
Yeah, but I'm trying to use Ch7. to access auto trim, and it just doesn't seem to be working.
I wonder if my problem is actually related to what some others are saying are problems with 2.5.
I just remember, when I first had my APM, I could pretty much let go of the cyclic, in Stab mode, and it would just stay where it was. Now it doesn't do that anymore. It always wanders, and I can't seem to get auto-trim to work.
Also, I can't see those leds, and it takes me maybe 15 seconds to spool up, leaving me with 15 seconds to get into a good hover? Not gonna happen.
I just fly my quadrocopter with the amazing firmware 2.5 and I am very happy, Stabl Mode, Alt-hold, and Loiter work fine for me, i will test RTL and Auto soon :) :)
Here is my setup:
Gaui 500x, 900Kv, 10x4.5, esc hobbyking blue serie 30A
APM 1 (1280),
Marco PIDs. :)
Thanks to dev Team, great JOB
just came in ,did some test flights.Stabilize works great,rock
solid.But i can´t get atthold working,just drops down with low rev motors.Put atthold P on 0,800,makes no difference
Using Marco´s params except atthold as mentioned.Sonar is working properly.
APM 1 2960
Set your throttle trim to about 550 in the left pane of MP, try that , if it still sinks, up it some more. I'm sure this will be 'developed' further, but it will get you in the air and alt-holding in the meantime
Oh did i have a good day at the field, video to follow - yes more homage to 2.5 and the dev team :D
Did you mean THROTTLE RATE P in the Configuration screen in MP? The default setting is 250.
As Dave said,in the left pane "TRIM_THROTTLE"
Thanks for the avice,will try tomorrow and report.