Today, the second time I noticed that the motors began to spin for a short period during booting of Ardupilot and probably the FETtec esc. I was able to lock to motors from spinning by hands and arms (the drone stands on the table in my workstop…), but its extremly dangerous and I never see that with Ardupilot until today…
The esc is brand new, but I’m not able to connect over a UART adapter. So I don’t know the firmware is flashed on the esc. Fettec flightcontroller as a interface for firmware flashing is ordered.
What’s the best way to investigate this critical issue? I will set the parameter LOG_DISARMED to 1. Is there anything I can additionally do?
Thanks, I believe that the wiring is correct. I did a few flights with the drone. But sometimes the esc goes crazy after connecting the battery as it shown in the two videos.
Is the onewire communication prone to emv problems? Maybe I will change the communication between the esc and FC to DShot…
I’m not sure of the solution but let’s work through a few things.
For a start set these so you dont have to go near the copter for the (non)safety button. You do still have to connect the battery of course.
BRD_SAFETY_DEFLT,0
BRD_SAFETYOPTION,0
I’m also inclined to try BRD_BOOT_DELAY,3000 and see if that has any effect at all. Even if it doesn’t you can leave it in place anyway.
Do you have a signal ground wire along with the Tx and Rx connected between the FC and ESC?
You list a 4in1 ESC so those signal wires should be very short right?
Long motor wires are not a problem.
DSHOT also has a checksum for it’s data, but there would be quite a change of wiring to connect up the ESC to do DSHOT. It would be interesting to see if the same problem existed.
Before you fly the copter again connect to MissionPlanner / Setup / Mandatory / Initial Parameters
Enter your prop size
Enter your battery cell count, and select battery type if it’s not LiPo
Select “Add suggested settings…”
Hot the Calculate button
Now accept everything related to battery voltages - DO NOT skip any.
Parameters already matching calculated values wont appear, only ones that need updating you could probably accept all.
These correct battery voltage values and failsafe actions are extremely important. Even if you do watch battery voltages closely, this allows the copter to save itself if a battery has a bad day or something unexpected happens. It also aids performance to have the MOT_BAT settings correct.
Thanks to all for your answers. Good news, I have found the problem. It was a EMV problem. If the signal wire is too close to the power wire it cause a problem during booting. After that, it seems not to be a issue, the motors start normal.
After the modified cable routing I plugged in the battery roughly 10 times, no issues!
Regarding the uncompled tuning. Thanks for pointing out the important parameters. I know, that I have to complete it. I just want to see if the drone flies with the new flightcontroller placement and dampening(regarding compass and vibration issues) and check the effeciency. After fxing the EMV problem, I can spend time on proper tuning
Quick question what’s the reason only using one wire? BTW the Caps can get hot and melt wires as well, I decided that i really don’t like to use them in my smaller birds.
I got in the past initializing problems with Dshot ESC’s. Sometimes not alle ESC’s got detected at the startup. This leads to some flips of the drone (when the pilot doesn’t realize it)…Now I’m hoping that the one wire protocol doesn’s have this issue. Tht’s the reason why I chose one wire.
When you configure the min rpm parameter like explained in the ArduPilot methodic configurator software, it will detect when one or more escs are not correctly initiated and refuse takeoff
I was too happy too soon. Today I plugged in the battery and the motors starts randomly during the booting… I did it nearly 10 times. One time I thought everything booted correctly, after arming the motors didn’t spin…
When I disconnected the signal wire from the flightcontroller, the esc doesn’t beep, and the motors doesn’t spin randomly. So there must be a problem when its connected to the flightcontroller.
It’s really strange… Next I will change the wiring and the parameters to DShot. Any ideas what’s to test next?
BTW, I contacted several time FETtec. It’s very disapointing, I never got a answer on my requests… Are they still in business?
