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.
How about an accelerometer reading during each motor run to help with prop balancing?
Good idea, John!
tail to me is another way to call arducopter SIMPLE mode - Good for new pilots. Yaw is calculated out so forward stays forward, no matter what orientation,,,if you dig thru this (and other) blogs you will find a lot about it....APM for me is a much better project than DJI....just check about waypoints....wookong is 6x more expensive...also you wont find such a large comunity willing to help anywhere else on web...GO WITH APM2,for the price of DJI you can make hexacopter for example...
Thanks for the clarification. I am sure my colleague will be blown away with APM when he sees it. He has been flying a Wookong S on his 700 class collective pitch Heli for AP for some months now, so he is somewhat invested in DJI. He is now in the process of building a Hex and bought the DJI. I think after he sees APM2, he will soon change his mind. I am a huge proponent of Open Source projects because of the large support community. Problems seem to get fixed literally overnight in an OS project thanks to the dedication of the community.
ArduCopter V2.3.1 - My new CLI Motors Test for the incoming release
1) Connect usb port to APM, launch the planner and enter the CLI mode (do not connect the main LiPo battery for now!).
2) Type 'setup' and press <enter>.
3) Type 'motors' and press <enter>.
4) Connect the main LiPo battery without disconnecting the USB cable, do not turn on your tx, is not important.
Wait some second while APM initializes your esc.
5) The motors will now spin in sequence, each motor will spin for less than 1/3 second at very low throttle and then stop, before the next motor will start after 2 seconds (3 with Y6 and X8).
Please observe direction of rotation of each motor to ensure it is turning in the expected direction.
First motor to spin will be the one located directly forward in the case of + configuration, or the first motor to the right of straight forward in the case of X configuration.
The motor test will then proceed in a clockwise rotation.
In the case of X8, it will spin the top front-right motor first, then the bottom front-right, and proceed around with the same pattern.
OctoV will spin the front-right motor first, and then again, proceed clock-wise until reaching the front left motor.
6) After the test pattern is complete, there will be a 4 second (5 with Y6 and X8) pause before beginning again.
7) When you are satisfied that the motor pattern is correct, or you wish to stop the test, disconnect the main LiPo battery and then press any key to exit from test.
Now if you want disconnect the usb port.
Thanks to Max and Robert for their support.
Here the video of the motors test on my heavy X8.
If you have suggestions are always welcome.
-= Marco =-
(AC Dev Team)
Thanks Tomas, you like it? It's easy? :-)
0:54 That looked like it stung ;)
YES. MARCO, GREAT, AND VERY USEFUL
FOR OCTO QUAD, I USE THE CONFIGURATION OF PARALLEL ESC,
Or I HOPE THE PUBLICATION OF NEW CODE.