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!
Graham, one thing that stands out to me is that you are using rate_I and stab_I together. That's pretty much my only tuning no-no, always gives me strange performance. Maybe try tuning just one, with the other at zero. Let me know if you see the same benefits I did. Btw I prefer rate_I. Cheers
Thanks, I had it like that after much CH6 tuning/testing but I've now put STAB_I to 0 and will test and report back.
Have put STAB_I on 0, but I actually think I prefer having both on, gives a more locked in feeling to my inputs. Will do some more testing.
Dave could you please explain the effect Rate_I has on flight in Dummies terms. LOL
Peter, the I term is a parameter that builds up while there is an error.
It is mostly used to account for external forces that are affecting the reach of the target.
To make thing simple, STAB_I is computed from the error of your stick, so if you have an unbalanced quad and keep your stick in a certain position, an error will build up and added to the control loop.
The effect if that after a short time your quad will be level without stick input.
RATE_I is computed from the error of the stabilization loop and is directly influenced by how long your quad takes to stabilize on the given input.
In my opinion at the end they almost do the same, only on different levels that's why you shouldn't use them together.
Personally I prefer to leave STAB_I to 0 and use only RATE_I.
A too high I term will lead to overshoot the target, thus creating a slight wobble after stick input.
Too low, and you will notice it will not be too reactive on error input.
Hope this helps.
I have a medium-large Y6.
Any recommendations on a good starting point for RATE_I?
Start with a 0,020 or 0,015 it works fine for me.
Thanks Emile, that's just what i would have said :)
Emile thank you very much I can now picture what I am trying to achive with the I term.
Your help is greately appreciated I have been chasing my tail with the tuning.
can somebody tell me is this original or not...i do have APM2 but friend asked me where to buy,and he found this http://www.goodluckbuy.com/ardupilot-mega-v2-flight-control-purple-...
Emin: That's pirated. Good luck to anyone who buys it. (we won't support it)
i would like not to ask this question at all...it is like bad comercial...