12 March, 2017 at 05:06 #36841
So I got in a crash and broke a VTX, props, and some other stuff. It was about a 40ft freefall. Anyway after doing repairs my servo is acting up. It goes full right as hard as it can every single time I power it on. I tried tuning it with tailtune but then after it had messed up quite well I realized that the servo feedback wire had sheared (most likely from a cold solder joint). Anyway I’m trying to fix a servo that will not correct and I’m looking for options.
I’ve tried reflashing the board but it does not show up in the firmware flasher after I hold the boot pin while turning it on.
I don’t know if there is a way to delete/remove tail tunes from the settings if so that would probably work.
If @lauka sees this I’m sure he would know what to do.
Looking for options, best regards aoym.12 March, 2017 at 06:29 #36843The-One-Who-Never-CrashesParticipant
Try re-centering the servo and re-soldering its wires. Also check if you’ve damaged the FC.12 March, 2017 at 08:29 #36844
From which point did the feedback wire shear? The feedback cable could be connecting to some other pad/cable. I had this happen once when the feedback pin was configured wrong.
Can you try to disconnect the servo from the FC, just have the power to the servo. Does it still do that?12 March, 2017 at 09:34 #36845
The wire sheared and didn’t seem to touch anything from the looks of things. I have reconnected it and it still does funny things. I’ll try in the morning just to connect it to power and see what happens13 March, 2017 at 04:58 #36848
So lauka I have disconnected the servo from FC and the servo does not move. It still had power it does not do anything silly. Now I tried reconnecting it and it still does the same thing. I have a youtube video here.
I don’t think the board is defective and I think a quick reflashing would work a-okay. My only issue is I can’t find the board after I have pressed the bootloader buttons >:(. I can still connect in cleanflight but I have not been able to get it to work in the board flash page.13 March, 2017 at 09:47 #36850
You could try unplugging the servo from FC (signal and feedback) and connect it directly to PWM channel on your receiver. Does the servo move normally then?
Then try connecting it to the FC but leave the feedback cable out.16 March, 2017 at 06:49 #36887
Sorry for the late reply Lauka I have been quite busy the past 48 hours. Anyway I have done just that and attached the servo to a pwm channel. The servo is still spinning full right with no stick input while it is in the aileron channel of a receiver. I’m going to go with this servo is fried. I think one last 40ft fall did it in, which I mean I can’t be too mad about because that thing dropped from 40+ ft onto the servo or partially onto the servo at least 5 times, twice on asphalt.
Sorry about the poor quality (it was dark in the room) but here is a video I took of the servo. You can hear it spinning constantly the second it is powered with no input from any channel (it should have input from channel one, aileron in mode 2). Oddly enough when I turn the Tx off the servo stops dead. When I restart it it keeps going. I must admit I was skeptical that the servo was the issue but you were right on the money. I’ll probably be purchasing another servo tomorrow but I’ll wait until you respond in case I’m missing something silly.16 March, 2017 at 08:42 #36889
Huh my post doesn’t seem to be showing for some reason so in case something happened to it I’ll go ahead and rewrite the gist of it.
I did do the PWM setup as you suggested and the servo continues to spin to the right for no reason. I’m not sure why this is but I figure its likely because the servo is just plain shot. I can’t complain too much because that servo has survived 5 crashes that were 40ft and above, with at least two of them landing almost directly on the servo mechanism. One last high crash on grass seems to have done it.
Here is a video I did with it on PWM sorry about the quality it was dark.
Anyway the servo started spinning constantly the second it received power and signal, and the servo stopped spinning as soon as I turned the Tx off. The servo should have responded to aileron but in fact did nothing for any channel. I’m going with the servo is borked, but if you’ve got anything else for me to try I’ll wait for your reply @lauka so I don’t buy a servo that I don’t need. But I’m expecting very much that I’m going to have to buy another servo. Oh well.16 March, 2017 at 09:45 #36891GAntonjoModerator
@aoym: I found your post in the spam filter. Not sure why, but at least here you see both your last messages;-)16 March, 2017 at 11:54 #36893
You could open the servo and inspect it for visual damage, solder joint breaks. Problem is most likely in the potentiometer, check that the feedback wire is not touching any other pins than the middle one. Check that the potentiometer is turning when you rotate the servo output shaft.
Try not to open the output gear side, only pry open the side where the wire goes in.18 March, 2017 at 04:05 #36917
I went to disassemble the servo and realized I do not have the bit to disassemble it. xD So I just bought another servo and the bit to disassemble it, and If I eventually take apart this servo and find what is wrong with it I’ll try to give an update here.
- The forum ‘Everything about the Mini Tricopter’ is closed to new topics and replies.