Hello,
I’m currently residing in the Denton area and I am new to drones. I am currently building a custom drone build (Holybro X650 V2 Frame kit) with custom electronics. My motor outputs vary significantly and I have calibrated ESCs even though I am on DSHOT600. Just yesterday, motor 1 started to rapidly change it’s thrust when put to max value and eventually started smoking and is now irreparable. I am unsure of how to get the motor outputs to stay the same and I would like to see if anybody is willing to help in person. The motor output for motor number 2 is also not the same as the others.
Hi - there can be quite a few reasons for motor output fluctuations - from hardware issue (faulty ESC, soldering issue, signal issue, partial short cut due to wires strain shorting or motor screws too close to the coils,…) to software issue (inadequate filtering, PID tuning, …)
Some questions that come into mind:
Are you testing your motors through the FC connected to a computer or are you arming the drone?
What FC software are you using?
Do you have any logs that shows the output fluctuations?
Any pic of the build you mind to share?
Thank you for those - bringing more questions I am afraid
If you test without arming - using direct control - are you able to test the motors (without props) and do you see this fluctuation you are mentioning?
This test would allow you to confirm there is no obvious ‘hardware’ issue with your build – You want to push the motor a bit - make sure to give them some airflow - liek a fan - if you are running them for any length of time as they will get hot)
If you can see fluctuations - then something is wrong with the hardware (could be ESC or FC) / connections / soldering / …
If no fluctuation then and only showing up while arming – it is likely a pid tune issue
Regarding the video - all motors seem to run - bit surprised there is no drone mvt at all as they even seem to run quite fast (based on the sound) - what props are you running? Are they the recommended size/pitch for the build? (how did you choose the motors/esc/props if I may ask?)
Were you just holding a low constant throttle? Or were you expecting it to take off?
I did a test without arming and I have the bokeh plot for the motor outputs which is the attachment shown. I can attach the bokeh plot with arming. After doing so, one of the motors had a dead short releasing smoke meaning I had to replace it; however, the fluctuations remained. As for the propellers, I’m running Tarot 1555 15" blended cf props with tarot martin 4008 motors as recommended by tarot, I chose the Tekko32 F4 45A as it fulfilled the requirements and fits neatly onto my frame. I pushed the throttle gimbal to the max expecting it to takeoff but nothing happened. I think it maybe be cold solder joints but I have resoldered everything and still got the same results. I think this points back to the FC.
Did you triple check the motor direction / prop fitting? If you had all the props the wrong way around (pushing down instead of up) then this would tally.
Small variations in the drone position (digging in) could explain the motor variation even (gyro trying to compensate)
Thanks for replying,
I’ve found that the motor direction and prop fitting is correct as per the manufactorers instructions and the props push the right way as thrust is directed towards the ground. I initally believed it was due to the drone position so we corrected it but to no avail and the same result remains.
Did you flash a recent AM32 on them? Did you set the kv settings to match the motor’s? (pretty much everything other settings can be left alone most of the time)
What manufacturers instructions?
You should be working to the setup guide for the flight firmware you are using
What are you using?
Edit: just seen you using a PX4 controller, what software level are you at? Are you using Mission Planner? There prop/motor assignments can be confusing
Update:
After resoldering the motor connections I found out it was caused by signal inteference as the signal wires and ground wires were space too far apart. After fixing this, the motor outputs no longer fluctuate thankfully.
Thanks to everybody who helped come up with theories, I greatly appreciate that.
Thank you.
