I have a problem after updating AC to 3.2.1 from 3.1.5.
When in Loiter, the the speed of the motors rev up and down/pulsate quite rapidly. This was working fine when I was using previous versions of arducopter.
I have downloaded the logs, and have looked into accX, accY and accZ. These seems to be inside the range specified in the wiki at arducopter. (Log_vibrations.bin)
Please have a look at the Log.bin, and note the difference between ThrIn and ThrOut when I'm in Loiter mode.
Anyone having any idea what the problem may be?
I had the same result after updating, shows up in alt hold and loiter. Not looked into this yet as mainly fly in stabilise but can really only be overcompensating throttle to maintain altitude. I'll have to suggest doing an autotune or manual tune this is the first thing I'll try when I get around to it.
I have the same problem after 3.2.1 update with quadcopter and APM 2.6 in althold and all gps controlled modes. I found that the barometer values are very unstable in newest firmware but Arducopter 3.1.5 version is without any problem.
Thats interesting Petr, I'll have to check flight data and see whats happening my end. To be fair after a few flights it seems to be more settled but still evident. The other variable is that when I first updated firmware and saw the problem it was stupidly cold which may have been affecting the barometer? I've completed a new build so have been flying all 3 multis recently and upside is theres been nothing more sinister than the pulsating throttle values shown. MY 550 quad is built for speed and runs on 4's, I've been hammering this around flat out, battery after battery and had no issues in stabilise mode, I normally do an alt hold and loiter check straight after take to ensure gps is working incase I need to rely on any failsafes and position hold is happy as is altitude hold apart from the above effect.
I have tested firmware version 3.1.5, 3.2 and 3.2.1 in APM 2.5.2 and 2.6 with the same result .
Version 3.1.5 is best in altitude controlled flights but a little less stable in Stabilize mode.
Version 3.2 is average between flight performance in Stabilize and Althold mode.
Version 3.2.1 is best in Stabilize mode but horrible in Althold mode. Displayed altitude fluctuate between -1 to +3m even at ground level. (version 3.1.5 fluctuate between 0-0.2m)
This firmware in a flight at low altitude bellow 3m also very offen issue a Land command.
The outside temperature was about 10C in all flights.
I have now made a video showing the behavior in Althold, Stabilize and Loiter.
To me the barometer values looks ok, so I really don't know what is going on..
Please have a look at my video here.
No I havent tried that yet. If I do I loose the scaling on RSSI voltage. I currently use FrSky receiver, and it gives out 0-3.3V, and not 0-5V wich is the default in 3.1.5.
I had exactly the same issue, but with that difference, that I had 3.2.1 firmware from start.
After some reading I run into APM forum topic, that was telling about altitude drift.
Following suggestions I flashed 3.1.5 without changing ANYTHING else.
Magic! It worked! On top of that I got old console back (without mavlink binaries falling to console) and need to download logs via console, which is tolerable imo.
Verdict: ArduCopter 3.2.1 need extensive debug and is not ready for release.
well ill be damned....I just posted a new thread on this same similar problem and I just downgraded to 3.1.5 like you guys suggested and its smooth as a baby now, no surges at all....all problems solved!!
I also have this issue with 3.2.1. Worked fine before with older firmware. I have tried tuning the throttle PID´s but have not had any success with that. Anyone know where to look? is it fixable with tuning or is it a bug in firmware?
I honestly tried to make the best of PID tuning, but if "alt hold" had satisfactory results in 3.2.1, then in "loiter" mode it was "blowing the roof of".
I guess there's and issue in math. EKF likes to do "additive alt increase" bu it was said that in new firmware EKF is not enabled by default.
Anyway, flying good on 3.1.5