Hi everyone, This is my first post...
I have my Arducopter configured as a tricopter and I have loaded the latest AC2.0.40 Beta firmware using the APM Planner and am using the default PIDS.
When the flight mode is set to stable, I notice (both on the ground and in the air) that I my yaw motor does not travel the same range when inputing a full stick right. I have a bout a 20 degree deflection to the left, and only about 5-10 degrees to the right. This has the effect of a very slow yaw in one direction in flight.
The second issue is with the yaw not centering. If the yaw stick is moved slowly back to center, the yaw motor does not level out entirely, causing the aircraft to continue yawing whilst in flight. This issue is corrected If I centre the yaw stick with a hard left, right and centre on the yaw stick. If I adjust yaw TRIM to about 75% to the right, the centering issue goes away, however the aysmetrical yaw travel issue is still present.
The above two issues are not present in the acro mode.
Thanks for any help.
What version of Mission Planner are you using?
I thought that might be the case.
The current MP is 1.0.76, and the current ArduCopter is 2.0.46
I do not know if it will solve the problem, but you will most likely want to upgrade.
The code was moved from svn to GIT, so you will need to download a new copy of MP, it might not update from the version you have to the current version (because the locations changed)
If you want to upgrade Mission Planner, go to http://code.google.com/p/ardupilot-mega/downloads/list and download it from there.
I do not know if it will fix your problem, but troubleshooting 2.0.40 is not a fun idea, since there are lots of major changes, and important ones.
If you update to 2.0.45 or 2.0.46, please erase your eeprom. Even if it says it is erasing it, just do it again in the setup. A leading cause of problems recently has been updated 'copters that do not erase the eeprom. Then redo the "setup" normally, with radio, modes, AC2, frame, etc.
Do you want to upgrade and then see if the problem remains?
master git repo, includes changes with arducopter, arduplane, mission planner and utils.
More than likely the issues will still remain. I am running 2.0.46 and have similar issues (on a tri). I adjusted my servo linkage to get the same amount of yaw in either directions however both left and right yaw are a bit slow. Also when you stop a yaw you have a 'bouncy' effect where it oscillates left and right for a few moments before finally taking a heading.
ArduCopter has had Tri issues (the bouncy yaw issues also on quad) for some time and yet to see any improvement, It was suggested on another thread that doubling (or more) your yaw rate P will reduce/stop this yaw bounce. I have yet to arrest this behavior.
For this reason I myself will be trying an OpenPilot CopterControl board as it seems to work well for most with Tricopters.
Also I would like to add that servo travel is only a fraction of what the servo is capable of. I may take a closer look at the code to try and determine how to increase this (which makes yaw slow).
I also have this yaw problem on my tricopter. I've tried 2.0.39, 42 and 46 and the problem remains. Currently I'm back to 2.0.42 and have changed the deadband value in the radio.pde to 150 this gets rid of the deadband problem......BUT the yaw drifts and you get occasional erratic behaviour in altitude hold.
In my opinion the ACM tricopter version is unserviceable.
Hi, running 2.0.46 I had similar issue with bouncing yaw on my tri. I solved it by tuninng yaw parameters, but not little bit. I'm not sure now, but I doubled P and did something with I.
Maximum servo travel is really small.
Copter really hold yaw well, but I feel hard to change it. It feels like sticky.