I've been using a 3DR RTF Y6b with Pixhawk since early summer with no problems. I never play with parameters. I normally would fly with the tarot gimbal and GoPro camera, but I wanted a better camera option for my purposes so I have a stable mount with a Canon Powershot attached. I've been swapping out back and forth the tarot gimbal with GoPro camera and my DIY mount with no problem most of the summer. Just recently, when I was flying with the Canon camera, my Y6 started twitching and bouncing around erratically in loiter mode. When I switched it to auto it would perform a mission just fine.
A couple flights after this began, it's now been displaying that same jumping and twitching behavior in stabilize, loiter, and auto. It is jumpy enough in auto where my photos actually turn out blurry because of the sudden movements.
My question is does anyone know if this is a tuning issue that I would just have to change parameters when I swap camera mounts? If so can someone suggest which parameters? I am a beginner and I have list of changeable parameters but I have no idea where to begin. I've sent the log files in to 3DR Support, and they've checked everything and can't see anything unusual. Also, i'm not sure if this would solve the issue anyway, since its been working just fine most of the summer and I feel that the weight is pretty balanced with my DIY mount.
The only other thing I considered is the temperature drop this month. Does anyone have any experience on how cold of temperatures these things can fly in?
I appreciate any help, Thanks!
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Hello,
I connected my 3DR Y6 to Mission Planner, hoping to check calibrations, and I noticed the top back motor wasn’t spinning. I just recently (a couple months ago) replaced that motor because it wouldn't spin. I did the necessary ESC calibration before replacing it, and it didn't fix anything, so I replaced it. I did the ESC calibration again, did some test flights, and everything worked well. I haven't flown for a while since, as the weather has gotten pretty frigid and snowy here. I'm wondering if the ESC has to be calibrated that frequently for the motor to spin? It just confuses me because I had flown very frequently all summer with no problems with motors not spinning. The other thing I noticed is there is a firmware update (V3.2). Would a firmware update have anything to do with the motors? I didn't want to update yet in case anyone had problems with V3.2 so I thought I would check on here? Any suggestions would help
thanks!
Just an update to this discussion. I performed my ESC calibration successfully and the beeping sequence that indicated ESC low voltage seems to have stopped, at least so far so good. The Compass calibration that Alex suggested seems to have improved my flights when I have the tarot gimbal and GoPro camera attached. I noticed some of the jumping after I first did the calibration. I landed and launched again and I didn't notice it any more. I didn't perform the compass calibration before I attached my DIY mount and Canon camera because I wanted to see if it would have made a difference. When I attached that DIY mount, the jumping and twitching was as bad as ever. My next step is to perform that compass calibration with the DIY mount on, and see if that fixes the problem. I'm not sure when I will get to this because of bad weather, so I thought I'd throw an update on here anyway. I have noticed that ever since I upgraded to the most recent firmware and Mission Planner version, it seems that my loiter radius is huge and it hovers pretty far away compared to how it used to. I read somewhere that I can't adjust that in mission planner like I could in older versions. Does anyone know any more details about this?
Thanks!
Did you balance the CG (e.g. move the battery) after attaching the gimbal etc? Balancing is very important.
Yes I've tried moving the battery around and getting everything balanced. I'm just not sure that if it was a balancing issue why it would happen suddenly when most of the summer it's been flying really well, unless it is a gradual thing?
I guessers you have not changed anything but the camera and mount and you have been flying ok then it pints towards mechanical or equipment issues.It is unlikely to be software as it has working and there arte others flying with no similar problems.
When it twitches and jumps can you identify the motor or at least the arm that has the problem? Or do all motors jump?
If you can identify a particular arm the possibly it is a motor or ESC going. Check the temp of the motors and ESC's after a flight. If you find one is hotter than the others then it may be suspect. One of my little 250 quads had a faulty ESC that would fly with no problems but occasionally would not sync on start. This started after a Fe months of solid flying. I thought that it was something else as when it flew it never had any issues. Replaced the motor, no change, relaxed ESC and all good.
Like anything mechanical motors will go eventually and ESC's can have faults that, over time, become noticeable.
I am sure you have done this but double check and make sure nothing has come loose. I have a Y6B also and the small jumper on the receiver to put it into PPM sum mode came off once. Luckily I found it without too much problem but it was glued in with a hot glue gun. The moral of the story, check everything and then check again.
Hi Alex. Thanks so much for your help! When it twitches and jumps I always thought it was unpredictable on which arms and motors it happened. Although now that may be the root of the problem. I was about to fly and this time when I armed the copter, one of the motors wouldn't spin at all. I decided to try an ESC calibration with no effect. I replaced the motor and now all motors are spinning fine. The only problem is the new motor I attached fires up and spins right away when I arm, and the others I have to increase to 3/4 throttle before they do. I believe I may have to perform the ESC calibration again to fix this, although if anyone has other advice I'm willing to try! Also, a beeping sequence has been happening now which 3DR Support believe is indication from ESCs of low voltage. They sent me some directions on what to do about this so I will experiment with that.
Also, I'm not entirely sure I'm doing the ESC calibration process correctly. It looks to be an easy thing and I'm going to try again. The first couple times I tried, the 4 beeps for my 4 cell battery did not occur, nor did the yellow light, or any beeps indication the calibration was complete. I'm not sure if I'm following instructions for the wrong type of copter or not.
Here are my .bin logs. I don't know much about what to look for in them. Thanks for taking the time!
y6badflight.zip
Morgan,
Thanks for the log files, do you by any chance have any older log files form a period in time before you began experiencing the "twitching"? Preferably on the same firmware. All the logs you posted have higher than what I would consider to be normal vibration levels, low .7s to low 1.0s. This puts you in the warning area for checks on IMU Mismatch. I'm curious to see what your vibration levels were "before". There are a number of things that can cause twitching behavior in earlier versions of copter code. I'm not especially qualified to analyze any of them specifically, however I do know there are parameters that can, if not set properly, accentuate the twitchiness. Randy says a number of these situations have been improved in 3.2.
I'm tending to agree with Alex that this probably has a root cause in something mechanical, but an older log for comparison could help confirm that.
Regards,
Nathaniel ~KD2DEY
Thanks for looking at the logs Nathaniel! I've uploaded some more logs but I can not remember the flights that went along with them. I've honestly no idea where to begin with analyzing .bin log files. The more I get into this though, the more I realize how useful it would be to learn so I really plan on taking the time to dig into logs! I wasn't sure what to look for in these logs and which ones to choose to upload that would be of use to you. I have many more if you need other options. As for the vibration levels, that does make some sense to me. I was worried maybe the DIY mount I attached to my Y6 might affect that, since I read on a forum once that someone warned against that if I remember right. Maybe I need to look into those parameters a little more.
32.BIN
91.BIN
40.BIN
Hey Morgan,
Thanks for the logs. Well the logs you provided were from a few different firmware versions and all display the same general characteristics, although the vibration levels in these three logs are lower you can still see you need some work to reduce the levels of vibration. I don't see anything that jumps out at me to suggest a cause for your twitching in the logs. I would try to isolate the problem an eliminate possible causes as Alex suggested. It sounds like it's mechanical in origin. In any case some effort to reduce vibration, and or isolation/vibration dampening of your FC would be worth the effort. If it does have any connection with your gimbal/camera setup, be sure to post back here as the Y6 is a popular choice with that setup.
Regards,
Nathaniel ~KD2DEY
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