Version 2.6 of the ArduCopter code is now available in the AP Mission Planner and in the downloads area!
Updates to MavLink 1.0 means you will need to use "ArdupilotMegaPlanner10.exe" to connect. If you've updated your mission planner recently you should find this executable in the directory where the mission planner is installed.
The above video is done using a prototype 3dr ublox GPS which seems to have better accuracy than the standard mediatek.
Improvements over 2.5.5 include:
- MavLink 1.0 support (use with ArdupilotMegaPlanner10.exe) [Tridge, Craig]
- Stability improvements especially during level hover [Jason]
- throttle range improvement (higher min and max) [Jason]
- improved standard Loiter PIDs [Alan, Heino, Jason, Angel]
- dataflash erase speed up ('+' messages removed but it only takes 6 seconds now) [Tridge]
- Copter LEDs [Robert Lefebvre]
- RTL loiter stage target set to home to improve final landing position [Jason]
- flip & acro improvements [Jason]
- circle mode target improvement for ground station [Jason]
- Auto Approach [Adam Rivera / Marco]
Bug fixes include:
- UBLOX driver fixes (lock should now be more reliable) [Tridge]
- enable mavlink messages during dataflash erase which resolves issue in which new APMs fresh from the factory appeared unresponsive [Tridge]
- proper printing of lat/lon values in dataflash logs [Randy]
- removed duplicate GPS reads [Jason]
- resolve flooding of telemetry link with low-battery warnings [Tridge]
- RTL bug would land if rtl_approach_alt was more than 1 [Jason]
- WP Radius could not be set larger than 1.3m [Jason/Randy]
PIDs are optimised for the 3DR/Jdrones quad with 850 motors and 10" props. If you're using more powerful motors/props and are seeing bad flight behaviour in stabilize, start by turning down Rate Roll P in 25% steps.
This time we spent some time optimising the loiter PIDs. Tuning loiter can be tricky so please refer to the discussions which will appear below for more community feedback on what parameters work best.
All feedback welcome below. Enhancement requests and bug reports can be put into 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 2.6 but tell us anyway!).
I have just uploaded the new ver 2.6 to my APM2 and its working a treat also noticed it loads a lot quicker with the MP Nav1
great work and cant wait to get this into the air and report back :-) keep up the great work.
It just keeps getting better :-) Congrats to all the developers
Is the optical flow sensor supported in this version?
Yes, it has been supported for a couple of versions now.
The soldering is a bit kludgy on an APM2, but it does work.
Wow! Just tried rtl and watched it land ON the takeoff spot. So far, I have had only 1 bug-
I have had this happen several times. I load a mission, then fly around, and at some point the mission gets corrupt. I did have good missions if I loaded and then flew right away,
Typically I load something like this-
After loading, I can read waypoints and it is fine. But after flying a couple batteries, it looks like this-
Is this happening when I change batteries? Or (I do have ch7 waypoint save enabled) is it getting a phony ch7 at boot? I will disable ch7 and try to duplicate.
I am confused as to what ch7 does to an existing mission - is there a way to clear the mission and do a new ch7 mission without a laptop?
Fantastic job, devs! 2.6 is absolutely amazing. I'm dying to give it a solid FPV test! I'm still having a problem though that keeps my confidence low.
I had initially thought my twitchy/jerky pitch problem (http://diydrones.com/forum/topics/tricopter-occasional-but-often-dr...) on my tri had gone away, as the first 8 minutes of flight with 2.6 release were rock solid. Near the end of the battery life (I get 10-11 with the 3.6Ah battery I was flying) it started happening again. Very slight, almost imperceptible, until just before the batt levels got low enough that I shut it down.
At that point there was one very visible, but not destructive twitch on the pitch (tail jerks down as if I flicked the stick). I just flew a full 5.8Ah battery (17 minutes of hover) and about half-way through I started seeing twitches, mostly in pitch but once or twice in roll as well. As I posted as a comment to my problem thread above, it seems to happen only if I'm putting tiny corrective stick movements to maintain location in hover. If I leave the sticks alone, I never see the issue (nor do I see it when aggressively flying so far).
I removed every single piece of non-essential gear (all video TX/OSD, second BEC for powering input rail, telemetry radio, etc.), I swapped channels on the TX/RX, etc. tuned pitch rate_P from 0.8 to 2.5, removed _D, etc. and nothing eliminated the problem.
Any thoughts? I'll record some video of it happening and capture a tlog of the same event and upload it to the original thread. I had a bad crash due to a very violent twitch that brought the copter down hard and I've been terrified to go higher than 6ft since.
Sound like you've eliminated most of the tuning/code issues, through the tuning you've done Could it be a motor getting hot and faltering? Have you done a quick battery change to see if it still does is at the start of the second battery?
Given the behavior that it seemed to happen more frequently at the end of the flight I thought the same thing. I have completely replaced the ESC for the tail, and I swapped the motor with another arm, so I don't believe it was a faulty bit of hardware. I thought perhaps the ESC (Turnigy 18A) or motor (DT750) is just not specced well enough to operate in this position (long shot, but thought maybe the rear motor gets a higher work-out than the other two), but I flew these with multiwii and KK pretty aggressively without a single problem. The motors and ESCs are actually barely warm to the touch after the hover test too.
Also, the problem before 2.6 was almost immediate, I could get it to twitch within 60 seconds then. I've got video and tlogs of that, I just need to trim down the video as its one long test session. I'm also going out to fly again now, so I'm going to try to capture 2.6 video/logs so I'm up to date. :)
In those logs, I see what appears to be a radio_in spike on ch2, which is something Glenn was seeing as well. His went away with 2.6, so I was hopeful something had changed.
I'll try switching out for a second battery right away and see if I can corroborate or discount a heat issue. Thanks for the suggestion!
Please get post some flash logs, most importantly, enable PID logging, and set Ch6 to tune pitch control, that way it will log the pitch control data. Very important.
I wonder if what's happening is your PID settings are stable when the battery is fresh, but as power droops with the bat voltage, you are getting some instability maybe due to your I term. If your I term is too high, it might be OK normally, but you only get into instability when motor power drops.
I attached a video and tlog (it's all I have of my first example) to a commend in the other thread: http://diydrones.com/forum/topics/tricopter-occasional-but-often-dr...
Honestly looking at the logs again, I'm having difficulty understanding what was cause and what was effect. There are strange anomalies like an xacc spike for the first jerk, but not the second. In both cases there's a fairly large corresponding input (ch2) change, even though I was at most moving the stick a percentage of a degree to maintain hover.
I'm charging up batteries again, and will try logging as you suggest, thanks for the suggestion.
Do you have STAB I with any value ? if so, set it to 0 and give it a try.
In 2.6 release I've got the default (0.1 I believe?). When I was diagnosing the problem with 2.6 Delta and before, I had tried dropping the stab I factor and rate D factor to zero. I also was experiencing the twitch in acro-only mode which I had assumed eliminated the stab PID settings completely. I've not tried anything but defaults in 2.6 release however, so I've got some repeat experimenting to do, and I'll try eliminating STAB I again now.