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Quad Motor Issue

Cheb2703

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I currently have an issue when flying my quad. Whenever I give the quad a throttle punch or try a roll or flip my quad flips out. I've tried different BF versions with no success. This is my BlackBox log. Could you take a look at it?
 
My bad, now I see it. It looks to me like it is the gyro being affected by vibration, or it is just bad. When you see the front motors spin up and the rear ones don't it is because the gyro is requesting it to counteract what the gyro sees as a huge pitch forward that was not requested by stick movement. The last time I had flip of death, I changed the FC and it has never done it again. Here is just one point in time, but you can see there is no right stick request, but the gyro says the pitch is at 230+ degrees, causing the FC to floor the front motors to try and stop it. That's the way it looks to me anyway.

1581996399135.png
 
My bad, now I see it. It looks to me like it is the gyro being affected by vibration, or it is just bad. When you see the front motors spin up and the rear ones don't it is because the gyro is requesting it to counteract what the gyro sees as a huge pitch forward that was not requested by stick movement. The last time I had flip of death, I changed the FC and it has never done it again. Here is just one point in time, but you can see there is no right stick request, but the gyro says the pitch is at 230+ degrees, causing the FC to floor the front motors to try and stop it. That's the way it looks to me anyway.

View attachment 3921
Yes, you are correct. I did some more break down looking as you did and I talked to another guy and I wonder if it is not the ESC that is the problem. If you look at the image I added then it seems that the motors start to drastically change before the gyro goes up. This would seem that the motor goes crazy therefor flipping the quad which causes the gyro to go wack and amplifying the problem. At this point, I do not know if it is the ESC board or the FC board. It is so hard to tell which comes first, the motor going wack or the gyro going wack.
 

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I agree, except for one thing... when I look back at my own BBL's I see that more than one axis of the gyro is always changing when others do, and if I look at the aircraft diagram in the top left I can see that it does show the quad pitching forward slightly to accompany the gyro change. In your BBL I only see the one axis of the gyro freaking out... ever, even though the quad appears to still be stable. In the screenshot below of one of my super old BBL's you can see I am in the middle of a roll and all the gyro axis's are moving during even a simple roll maneuver, in yours, only the one axis (pitch) is moving much at all. Once the gyro tells the quad to do the wrong thing it just gets amplified by the PID's and avalanches out of control. My money is still on a bad gyro.

1581999374628.png
 
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Here it is showing your quad in a roll, but still the pitch gyro is registering huge numbers in comparison to the roll axis even though the aircraft diagram clearly shows it is only rolling to the right, and that gyro axis is still very small (38 degrees per second) compared to the pitch gyro (209 degrees per second) and it is not showing in the aircraft diagram at all that pitch is at play here. I'm no expert, so I can't say for sure, but it sure seems something is off with the pitch axis on that gyro.

1581999754780.png
 
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Here it is showing your quad in a roll, but still the pitch gyro is registering huge numbers in comparison to the roll axis even though the aircraft diagram clearly shows it is only rolling to the right, and that gyro axis is still very small (38 degrees per second) compared to the pitch gyro (209 degrees per second) and it is not showing in the aircraft diagram at all that pitch is at play here. I'm no expert, so I can't say for sure, but it sure seems something is off with the pitch axis on that gyro.

View attachment 3924

Okay I do see that. Is this software or is there a way to fix this? Or is the whole fc bad and I need to get this one replaced because it is brand new?
 
It is likely a hardware or vibration issue, if your FC is soft mounted with gummies then I doubt it is vibration because only the pitch axis seems screwed up. You can try a reflash of the betaflight and do the minimum config needed to make it arm and fly to test it, but in all likelihood it is a bad gyro. Unfortunately there is no way to fix it really, and the cost of these products would be easy 2 times more if they did real QC on them, so some failures out of the box are just par for the course.
 
It is likely a hardware or vibration issue, if your FC is soft mounted with gummies then I doubt it is vibration because only the pitch axis seems screwed up. You can try a reflash of the betaflight and do the minimum config needed to make it arm and fly to test it, but in all likelihood it is a bad gyro. Unfortunately there is no way to fix it really, and the cost of these products would be easy 2 times more if they did real QC on them, so some failures out of the box are just par for the course.
Yes, the FC is soft mounted with gummies and I have already reflashed BF and flew it with no change. It seems that I guess I need to start looking into this getting replaced?
 
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There are no guarantees, but one thing I will say is that it doesn't look like anything the ESC would do, so I think the FC is the 99% option. My fingers are crossed for you! Let us know how things are going along the way, we will always try and help you sort through it.
 
There are no guarantees, but one thing I will say is that it doesn't look like anything the ESC would do, so I think the FC is the 99% option. My fingers are crossed for you! Let us know how things are going along the way, we will always try and help you sort through it.

GetFPV got back to me and looks like they will be sending me a new FC. Hopefully, that works!?
 

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