Hey,
Having problems with different rpm values on the motors even after the ESC's are calibrated and APM is levelled. The problem first occurred after my last crash and at first I thought that the problem was in ESCs. As the frame was a bit damaged as well I changed my Y6 into X4(built a new frame), recalibrated the ESCs (Turnigy Multistars) and loaded the new firmware from MP. The quad somehow flied but really badly, sort of falled into one way and then brought itself up again then falled on the other side and so on.
I used the MP failsafe to observe the PWM values for each channel. It seems that if I push YAW for example then two of the motors speed up but after releasing the stick to the center position then the PWM values for these motors stay up. Sometimes some motors slow down a bit themselves and so on.
Replaced the ESCs to Afro 30 Amps but the problem stayed. Also thought that it could be an APM config issue but have reconfigured it several times with different parameters.
Could it be that the APM board itself is damaged? Or could it be something else, receiver, etc? Wouldn't like to order a new FC just yet.
Thanks,
Tõnis
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Could it just be the motors ? Damage to the bearings would create more kinetic friction in some. This would create less rpm per current input? The effect described would be more apparent at higher speeds due to power laws. P=fv. Other than that MAYBE the apm sustained damage, cracks in the silicon board could damage circuitry or maybe if you accidentally dropped a screw or something conductive on the board when the power was on you could've short circuited it. Sorry I'm not so specific with my ideas, I'm not really that familiar with the apm and programming.
Thanks for the ideas. I will have to check the motors in the evening. Could this explain also why some PWM values stay high up after acceleration? Just like there was a delay or something. One thought was that it could be a software issue with very wrong PID values but messing around with these didnät help as well.
I ordered a new APM from Hobbyking as well, should arrive by the end of this week. I wonder if thre's a way to check if and what is faulty if the reason is in APM?
I think for that I would have to know the circumstances of the crash? But pid settings are for sensitivity and as such dont deal with delay or something. I think for pwm output check the calibration of the gyros and calibration of the reciever?
Crash was due to human error, I flew close to buildings, lost the gps signal and crashed it into a nearby building. It came down from about 2-3 m but luckily fell on its legs.
I replaced some motors but it had no effect, some of them are still turning faster than the others. For example whith the quad placed level and 1/3 throttle some of the pwm values start slowly to decrease and some to increase. Then pushed yaw to the end and pwm for two channels increased but after letting the stick back to the center the channels stayed up.
The new APM arrived but still no difference.
I have recalibrated the gyros and receiver through mission planner. I don't think it can be the receiver because the inputs stay leveled when looking at the failsafe window in MP.
Just started to recalibrate my radio endpoints and it seems that when I center the pitch stick then it swings between values 1484 and 1476, yaw and roll are between 1475 or 1474. Could this be the reason?