ACRO bug (fixed in 2.9.1b): while doing flips in ACRO mode, if you switch to Stabilize while inverted your throttle will go to minimum. To regain throttle control you need to switch back to ACRO then back to Stabilize again (i.e. switch to stabilize twice). You never lose control of roll/pitch/yaw.
Loiter/AltHold/Auto/RTL bug: if you switch into these modes with throttle at zero motors will go to minimum until you raise the throttle.
Auto mode altitude bug (fixed in 2.9.1b): setting a waypoint altitude greater than 320m over home altitude may wrap around and instead be interpreted as a low altitude.
ArduCopter 2.9 is now in the mission planner and the downloads area!
The major improvement is we use inertial navigation to improve altitude hold. This increased reliance on the accelerometers means you must do some additional set-up before flying:
1. Perform the new accelerometer calibration in the mission planner (video). The auto-trim metho has also changed (video).
2. Add vibration dampening foam between your frame and the APM. Some suggested materials: DuBro, gel, hk foam.
3. If upgrading from 2.8.1, modify the throttle and altitude PID values:
- Increase your Throttle Rate P, reduce I to zero, increase D
- Increase Altitude Hold P, reduce I to zero
- Tune Throttle Accel P and I terms but try to keep P about 1/2 the size of I
Here is the list of major changes (a more detailed list can be found in the release notes):
- Alt hold using inertial navigation (Leonard, Randy, Jonathan)
- AUTO_VELZ_MIN, AUTO_VELZ_MAX parameters control the max climb/descent rate for the autopilot (cm/s)
- PILOT_VELZ_MAX controls max climb/descent rate for the pilot (in cm/s)
- Landing improvements (Leonard/Randy). Copter will descend to 10m or until an object is sensed with the sonar. Then slows to 50cm/s descent (speed can be adjusted with LAND_SPEED parameter). (video).
- Surface tracking with sonar (Randy/Leonard). Copter will attempt to maintain current distance from objects in front of sonar regardless of altitude. Only used in alt-hold and loiter, not used for missions. Sonar can be enabled/disabled with CH7 switch. (video)
- Failsafe improvements (Randy/Craig/John Arne Birkeland) including bug fixes, additional check for PPM encoder failure and implementation of battery failsafe. Set-up instructions are here.
- Mediatek gps driver accuracy improvements and use of SBAS [Craig]. Instructions on upgrading your mediatek to firmware 1.9 are here.
- Traditional Heli improvements (Rob) including (a) bringing heli code back into the fold, (b) enabled rate controller (previously only used angle controllers). (c) fix to rotor speed controllers - now operates by switching off channel 8. (d) allow wider collective pitch range in acro and alt hold modes vs stabilize mode (e) bug fix to allow collective pitch to use the entire range of servos
- Acro trainer (Leonard). Copter will return to be generally upright if you release the sticks in acro mode.
- ACRO_TRAINER : set to 1 to enable the auto-bring-upright feature
- ACRO_BAL_ROLL, ACRO_BAL_PITCH : controls rate at which roll returns to level
- Camera control improvements (Randy/Sandro Benigno): (a) AP_Relay enabled for APM2 (b) Trigger camera with CH7 or DO_DIGICAM_CONTROL command (c) Allow pilot override of yaw during missions and fixed CONDITIONAL_YAW command.
- PPM sum support for transmitters with as few as 5 channels (Randy/Tridge/John Arne Birkeland).
- Performance and memory useage improvements (Tridge).
As per usual 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.
Special thanks to our testing team lead Marco and the dedicated bunch on the 2.8.1 release thread who put their copters at risk while testing the pre-release version. Some of their videos are here: 1 2 3 4 5 6 7 8
Please feel free to report issues you find in the discussion below and/or add them to the issues list.
Replies
Hi,
I have a suggestion you guys might want to add as an option in a future release. I dont really need it but it has been on my mind and I thought I would mention it, if you havent noticed it already.
I read somewhere, (I think on the esc calibration page in the wiki) was talked about the dji esc's, I like these esc too and have used them with the apm. I noticed in the dji 550 flamewheel manual under spec's for the esc's (30a opto's) the signal speed max is 450hz. In the MP there is a setting, RC_SPEED I think, for 400HZ and for 490HZ but there is no way to set it for 450HZ.
I had run mine at 490HZ for a while and did not seem to have a problem but for safety I set it to 400HZ. I dont know if 50hz or even 90hz makes that big of a difference but I guess I would of liked to be able to set it for 450hz.
Like I said, I am not currently using the dji esc's but I thought I would bring it up for those that are.
John
I recently did a long-distance, high-altitude flight test of 2.9.1, flying up the base of Yellow Mountain for nearly a kilometer, then returning via RTL. It was a very successful flight altogether, despite the big mysterious crash at the end which broke my GoPro LCD. Here's the video:
I would like determine what caused the crash. After the RTL returned the craft to the home coordinates, the quad was still over 200 meters up, and I could see that it was going to be a long while waiting for it to come down. So in order to not use up the remaining battery during the long decent, I switched to LOITER, and dropped the throttle for the fastest possible loiter decent. Then when it got to just a few tens of meters off the ground, I used the channel 7 switch to flip back to RTL. The result was that the motors instantly stopped, and the quad came crashing down. I raised throttle, and the motors started again, but too late to recover.
Is this a software bug? I have verified in the logs that the mode went directly from LOITER to RTL, so there was no stabilize mode in between where the low throttle stick would have been an indication to shut down the motors.
Some other minor issues I noticed from this flight:
1. In the log file (attached) the Baro Alt overflows and goes negative when it reaches 2^15 cm (about 327 meters).
2. In the the KMZ file generated by Mission Planner, all the high altitudes are wrong in the flight profile when graphed in Google Earth. For example, my launch elevation was about 411 meters and I climbed to a GPS altitude of 810m, but the maximum height of the graph in Google Earth is 1210m.
I hope someone can shed some light on these issues, otherwise I will dig into the code myself once I get some free time to do so. Thanks in advance for any assistance.
Hi!
I've got some problem with throttle-control after the 2.9.1 Firmware update.
I fly a dji f450 frame with simonk esc, rctimer 2830/11 1000kv motors, 8x4,5 carbon-props running on 4s 5000mah batteries.I guess it weights about 1,7kg
Motors and props are balanced individually and together The arduino is placed 15mm over the top-plate to avoid any disturbance from the distributionboard.
I've used vibration dampers between the lunchbox and the frame, and earplugs between the lunchbox and the ardupilot. The raw logs looks pretty good.
My problems are:
1) When I used 2.8.1 it flew very well in stabilize mode, it was actually that mode I used most of the time. After the new update the quad won't hold altitude at all in stabilize mode. With the 2.8.1 firmware the quad would more or less hold it's altitude at about 50 percent throttle, with the 2.9.1 firmware the quad just want to climb or descend,it's impossible to hold an altitude. I've tried to turn down the throttle rate P from 6.0 and all the way down to 0,01, I've also tried to change the expo at my T9x.
2) Altitude hold only work if I just fly the copter over a very small distance. Say if i fly 20+ meters straight ahead, the copter will just descend, and not rise before I release the pitch.
3) Loiter works very well as long as there is very low wind, but needs some tuning before it will fight the strong winds.
I assume that I have to sort out the thottle-problem before I can continue tuning altitude hold and loiter. I've tried a little bit, but I feel that i don't get any improvements.
For all i know, maybe some of you experts immediately see whats wrong o_O.
Regards
Eirik
2013-03-14 22-35 21.log
Pids.jpg
Why my Y6 yaws so slow? Can I improve it? Tried increasing rate YAW I and P with no avail.
Forward to 2:15:
If after uploading the firmware you find some of your channels are backwards, is there a way to reverse them in the APM code or should you reverse them in your TX?
Hi,
I have a coupke questions about the PX4, I am hoping smeone that has both APM25 and PX4 quads will answer if they can.
I am thinking about getting one to replace an apm25 and I am wondering how they like the px4, how it compares? anything noticeable?
I am also wondering if there is anything else I would need to replace an apm25 on an existing quad other than the px4fmu, px4IO, and maybe an px4 optical flow?
One thing that has stopped me from ordering is this line in the revision notes
"BMA 180 sensor removed and left unpopulated, current board will work with MPU6000 sensor."
does this mean I need to add an mpu6000 to get it to work? what about a MPU6050?
thanks for any info on this,
John
I flew both my 450DJI crash-quad (APM1 board) with 2.9.1b and my big quad (APM2.5) today and both have an issue with loiter and alt hold. The crash quad bounced up and down about a meter and the big quad locks in ok and then just out of the blue it just drops down a couple of meters. The crash-quad fly's really well in stabilize. Could someone please look at my log and see if you can spot what is wrong? Armed starts in at 32% Loiter at 40% Althold at 43%
2013-04-07 10-07-38.tlog
Hi,
I have an observation, I guess that’s what best to call it. I have a copter on, basically a x525 frame, with the gps on top (above the apm) on a grounded copper filmed piece of plastic. It flys great, it auto lands great. That is until I put a cover over the top. Pic’s below.
Once the top is installed, (over the gps too) it will “bounce” (kind of stop, then fly back up) when landing. It does this "bounce" one time every time I land, with the cover on. I remove the top and it lands and the motors shut off right away, no bounce at all.
Does anyone have any idea why this is happening? Or is it all just coincidence? Ive done about 10 landings, with and without, the top installed?
I am thinking it maybe has to do with the gps, maybe the cover is messing up the signal timing for the alt, though, the alt does not change in the MP if I put the cover on or remove it???
I have not tried to move the GPS yet, I had it on one of the arms with no ground plane, It seemsI get a better (lower) HDOP and more sats with the ground plane.
Any ideas?
John
Finally got to try the follow me mode on 2.9.1. Its so fun but kind of spooky too.
Bit clunky to set up but once it is going it feels like a puppy dog :)
https://www.youtube.com/watch?v=L7dmiUgbvaQ&feature=youtu.be
Hey Guys
Just rebuilt another frame, i had a look and could not find the XYZ vibration range anywhere
could someone tell me if these are in line.
in is complete flight 2nd is zoomed in on first stab section.
-
4
-
5
-
6
-
7
-
8
of 58 Next