esc32Cal on Ubuntu questions

[johandm_be]

Hi,

Up until today, I have always used QGC to calibrate my ESC32s.
Because of the warning that says ESC32cal support in QGC is experimental, I've set up a brand new system with Ubuntu 12.04 to use that to calibrate my ESC32s.

I only have limited experience with Ubuntu (or Linus in general) so there is a learning curve for me here. Still, with the excellent instructions here: I was able to get it to work fairly quick.

Now, I do have some questions:


1) when the esc32cal runs, it ramps up the motor in small steps (20->40; 20->45; 20->50; etc.) On windows these steps take typically 1 second each and are consistent.

When I run esc32Cal in Linux, it often stays a bit longer in a step (up to a couple of seconds).

I have seen that happen in Windows as well in the past, but then it meant I had a problem with my USB2serial adapter.

In Linux, I can't seem to solve this. I am running Ubuntu native on a machine (so it is not a VM inside windows) and I already tried 2 different USB2serial cables (both TTL-232R-3V3). To be sure I also tried 2 different ESCs.

Is this normal: the fact that it tends to loiter in one rpm setting for a few seconds every once in a while?


2) As esc32Cal is stepping, it always prints the max_current to the console per step. Something else I noticed is: from time to time I see that it is outputting the exact same max_current 2 to 3 times in a row. I am very suspicious about that. That almost can't be true.

Is this normal behavior, or do I need to debug something with my setup?


3) Attached are 2 graphs of the exact same current calibration: this is exactly the same setup just run twice in a row. I am running of a power supply so the voltage was also identical between these 2 runs. Notice how different the first term is. Is this to be expected?

I have also attached the telemetry output for the 2nd calibration (cal4)


Thanks and kind regards,
Johan.

[LPR]

Johan

Last winter I use Ubuntu to calibrate a ESC32 and noticed the same thing, it took a little longer to calibrate with Ubuntu. If the calibration of the ESC32 does not complete the calibration routine for me it has always been because I have the Max amp setting too high.

The Max amp setting should be set less than the Max amps the motor would use at the voltage you're using.

The lower you set the Max amps the less amperage your motor will use.

Larry

[johandm_be]

Hi Larry,

Thanks for your help.

You know, after I send this message, I ran some more tests and for some reason it started working correctly. It no longer had the occasional pauzes during the calibration steppen and it also did no longer repeat max_current numbers for different duty cycle ranges. It's strange because I have not changed anything to my setup, and still the problem seems to have gone away now.

If it does re-appear in the future I will try by lowering the calibration current as you suggested.

Thanks and kind regards,
Johan.