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.
Some hours ago I downloaded 2.4 from GIT and I had opportunity to do some rudimentary test flights in my garden.
I am puzzled though; as I understand it Loiter and Nav now have separate tuning parameters. Still, the only way to tune loiter gain seemed to be using Nav PID. Loiter Hold and Loiter pids did not have any influence on stationary loiter at all. Just like before.
Do I have to somehow "activate" the separate Loiter tuning or what?
Anybody else noticed this?
Explanation on the various Loiter/ Loiter hold / Nav / XTrack parameters influence on various navigation tasks would be most welcome!
Yes, because if you set the wrong mode the motors sequence is different for + and x.
No, I was refering to the flight modes. If you don't configure a flight mode like stabilize and loiter, or every mode stabilize the code 2.4 stays in acro.
Acro wasent present in 49 thats why it worked, I think.
I take it 2.4 has not been added to the MP yet?
I have tried to upload 2.4 with arduino 1 relax patch ver and have changed the code only for my Y-6 compiled ok but cant seem to upload it says uploading but just hangs ? Is there something I am missing?
as unable to try 2.4 :-(
We'll be adding it to the MP later today.
OOOOOo Chris thanks,
cant fly now as to dark :-( never mind always tomorrow.... any idea how long this will take?
Is there a possibility of adding a "squat" switch? In larger aircraft, you arm the spoilers for landing, when the landing gear collapse a certain amount on touchdown, the spoilers automatically deploy making the aircraft basically a brick at that point and it will not fly again unless the pilot disarms the spoilers. It prevents porpoising on the runway... Perhaps a small microswitch on one of the legs to sense grounding, then motors to say 25%... Ignore the switch if not in "Autoland"
Small video, test V 2.3.
Frame: Silver H, from Beedrones, Hexa frame.
Props: 10 x 3.8
Esc.: Jdrones 30 A, flashed with SimonK firmware
Battery: 4S, 3000 mHh, 40C
Weight: with camera mount plus 1 servo: 1920 gr.
Wind speed: from 7 to 14 km/hr
More tests and videos soon.
My Land (R. Martins (Portugal))
How do you like the flashed ESC's? Is it a big difference?
2.4 Outdoor Testing
DJi flamewheel, APM1, standard jdrones 850 ardu kit, 10*4.5 slow fly, xbee connected. Very light wind, I estimate about 8 kph above the trees coming from in front and slightly to the left.
Testing Stabilised, Alt-Hold (Baro only)
Strange flip when I first setup, quite elegant though!
Reconnected the battery and all was fine. Sifting through logs this evening to see if I can find an explanation. GPS bug maybe?!
Marco: I tried a few hard forward flights, no evidence of the nose rising so far, but may need a longer run.
Anyway, the video says it all – it’s great on my set up!
Test 2.4 today. It seemed very stable with less drift then I am accustomed to. I have been working on vibration isolation on my APM 2.0, which involves vibration grommets, o-rings, and foam (the whole 9 yards!).
After my third flight or so, I had an uncommanded roll which caused my quad to land upside down. I was about 4 ft off the ground, so there was little damage, but it was definitely disconcerting.
I attached my logs and a jpg of the occurrence. Any ideas? I am not past thinking it's my hardware, which has survived numerous crashes to this point. I am working on getting it back up to do some testing. Such a bummer to be so close and have this crash! It's the nature of the hobby I guess