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.
any idea when 2.3.1 is due out? I though it was going to be 3.0 for some reason.. don't know why though
Just installed a Savöx SH-0254 with 3.9kg/cm which a local shop had on stock. Also makes noise, but seems to work more precise and fluent. I'll have to wait for a test tomorrow.... I'll also have a look into the counter-weight attempt.
2.3.1 is undergoing flight testing now. If all goes well, we'll push it out this weekend.
OK, I couldn't wait till tomorrow, did a quick test. Result is still far from perfect, but looks better I think. Have to test again tomorrow in sunlight. Also had some fun blowing some snow ;) Video attached:
Great! Much better stabilization in pitch, have to get some new servos too.
I see it must be quite cold there since you have that kind of snow, do you have to wait for the sensors to stabilize in the cold? I have been reluctant flying lately due to the temperature and snow, but I am mighty tempted .....
I look forward to the upcoming release of 2.3.1 :-)
But, briefly, what are the fixes and news that we may expect for the release?
Yes, they should be decent. If they're not it most likely means that we've either got the fov of the lens or the altitude is inaccurate. Maybe you could post a graph or something?
2.3.1 is almost entirely bug fixes found since the 2.3 release so no great leaps in functionality this time. Marco and Jani are leading the effort to test this and we should have a release out within a few days.
We're starting to shift focus to 3.0 which will get us more object oriented and help us get the code to a place where more developers can add value without having to understand every line of code.
I flew 2.3 today and generated a tlog attached. The arming starts near 30% playback.
This time it is a square. Waypoints were added using CH7. They are added when loiter mode is switched.
The landing was a little rough and I see that has been addressed in next update.
It really works well in auto mode.
Next maybe is to have it point forward toward the next waypoint?
I am yet to use auto takeoff because a version in the past flew it fast and hard right up against a wall.
If anyone has verified the auto takeoff is reliable I will try it again.
The gopro gimbal test video is neat.
Next step is to add this.
Hey again guys, as promised, here is a very short clip of us flying aerials for a tv commercial over the weekend, using our octo and AC2.3 (loaded just before the shoot) As mentioned a few times before, it performs perfectly everytime and have now done close to 2000 flights using Arducopter. Thanks again to Chris, Jason and all the dev guys!
Last week it has been between -10°C and -20°C here. I had the quad in the trunk of the cold car for about 10 minutes on my way and another 3 minutes outside for setting up battery and waiting for gps fix before I flew.
I am a great admirer of your work. Can you please share some PID settings on your Octa. That Octa of yours looks rock solid. Do you use the same radio transmitter for camera tilt as the one for flying?