Jason is travelling this week, so I'll take the helm for the next software release post.
UPDATE: the motor remapping thing was confusing everyone, so we took that out and returned to the regular motor mapping. That means that APM 2 users with Hexas and Octos should wait for the next version. APM 1 users should be fine with any frame.
NOTE: Hexa and Octo users: there have been motor mapping changes that may affect you. Please don't upgrade until we can update the documentation to reflect the changes. This should happen by the end of the day today (Feb 1).
ArduCopter 2.3 is now available in the Mission Planner. This is the next revision of the ArduCopter 2.2B6 code, which is perhaps the most tested code we've ever released (1288 comments in the thread!) and certainly in my experience the best code, too.
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 (default is 0.14, so start by turning it down to 0.1. In general tune PIDs in 25% steps).
Now that we've got solid code out there, we can turn to collecting suggested gains for standard frames, and a better guide to how to tune PIDs for your unique setups.
Here are Jason's note on the latest changes (mostly from 2.2B6)
A dampening term called STAB_D has been refined. A D term for all of the Rate based control loops has been added based on Igor's work. Landing for Baro and Sonar has been refined based on JLN's work. A slightly new approach to Loiter and Navigation is being used to try and linearize the pitch and roll for rate control. It tends to use lower gains, yet has a more assertive response in the air.
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.
Note the Mission Planner does not yet highlight these D terms on the main tuning page (it will soon), but you can find them and modify them on in the Parameters list.
Autolanding should now work well (see video above) and the Tri servo issue is now resolved.
The code should now compile with Arduino 1.0 (thank, Randy!), but remember that you need to use the "relaxpatch" version of Arduino in our downloads section.
[Update: we've reverted the below. See update at the top of the post]
Important for Octo users:
We've changed some of the motor orders for some more exotic airframes. We'll be updating the docs on the Wiki in a day or two to reflect this. Pat Hickey explains:
As before, the hexa plus APM2 motor setup has changed from the ordering [1, 2, 3, 4, 5, 6] to [ 5, 6, 1, 2, 3, 4 ].
The Octa V layout for APM2 is:6 42 58 13 7Motors 1 through 4 spin clockwise, and 5 through 8 spin counterclockwise.
Have you see the linked page? There's an "X" in the table, means "yes"... :-)
I'm sure about this, some friends use 14ch with TM-10 module with Futaba T10, of course on the receiver you can only use 10 of the 14 available channels.
But there are very practical economic alternatives:
Is the same product by Fr-Sky, just branded in a different small box, for this reason, we recommend the "Orange".
In addition there is also the "T8FRS", which combined with a T8FR allows you to have up to 16 channels! :-) I use two of this combined on my glider ASW28 4.2 meters (12 channel, i've Futaba T12FG) and sent it up to 800 meters of altitude without losing the signal.
I've had 10 of these, never had a problem.
Ok! got it now. thanks for the links Marco.. At $30 to $40 compared to $200 to $350 makes sense to give it go for sure.
Yes but remember (important): with this receiver you must DISABLE any transmitter failsafe in all the channel, and use only the builtin failsafe inside the receiver.
To set this more carefully the manual:
If by chance you forget to do so you'll definitely interference on commands, such as throttle to zero in fly... remember that!
Noted and thanks again Marco
John, be a bit careful of Fr-Sky. I bought a Futaba Tx which came with a Fr-Sky 2.4Ghz module and rx. Had a bad crash, and only then thought to do a range check. It should have gone 30 yards, but failed at 2. Now it could be there was a problem with that module or rx, but generally in life, you pays your money... Regards, Bill
Any transmitter/receiver system can fail, until someone collects data from a few hundred Frsky users you can't say anything. (my Frsky works perfectly for example)
I agree Fabien, i've crashed a maxi 3d aerobatic plane 2.6 meters with Futaba 8 ch HS rx, some pin in flight are broken (internal strip solders) due vibrations, and the receiver was protected with plenty of foam.
If you analize the pcb of Fr-Sky receiver you can determine which is very well done.
Obvious that the defective part can always be there, and that's why I like test all my receiver as a "slave" rx, yes, 2 rx in flight, one tested Futaba with a lot of channels and the other one (Fr-Sky) connected to a single channel not much important (rudder), both binded to the tx.
I mean in a plane/glider, not with quad (LOL).
That way I can test the range of Fr-Sky without compromising the flight model, driven almost entirely from Futaba if there's problem with the "slave receiver".
Clever, no!? :-)
Bill, i not speaking of the Fr-Sky module, i talking about FASST systems!
Doesn't really matter where they're made, they are all using the same robotic pcb assembly equipment. As long as they are calibrated equivalently, the quality of the build will be the same. All the components are manufactured by the same suppliers. It all comes down to choosing the tolerances of all the components, circuit design, and packaging.
Besides, it's well know that Futaba radios are made in China.
I am not actually a fan of Futaba - in fact I am considerably annoyed at the way that they have produced 2 2.4Ghz systems which are not compatible, that a 7Ch rx needs a Tx module switched from 8Ch to 7Ch, that my 9 channel Tx, can only use 8 channels with a 2.4Ghz module etc. etc. At some point, when I have the money, I will get a system which I can use on all my models with no fr***ing about. The point of this detour in the thread is that generally every time I have tried to use a cheap option with these quads, it has not worked well for me and I had a particularly bad experience with a brand that I was just warning somebody about. Nuff said, let's stop this now. Bill
You bought the system used?
I'm running the Fr-Sky Tx module and receiver, no problems at all. I've seen some be so bold at to say the Fr-Sky system is better than Futaba.
I'm mostly using Spektrum DSM2 complete systems, and FrSky modules in a JR 9XII.
I've also tried to use the "Orange" DSM2 stuff, lost a plane, and a heli.
I'll swear by FrSky, using it in helis', my H9 Twin Otter, my Discovery UAV.
I trust it more than my original Spektrum equipment.
My 2 cents worth.