BDShot telemetry in logs

ArduPlane VTOL Plane
1

I’m looking at ESC telemetry in my flight logs. The main, analog power readings make sense. The individual ESC reports confuse me. This is the first time I’ve used DShot ESCs, so I can’t tell is this is normal or something is wrong in my setup.

For context, this is a quad tailsitter. 4x 1804/2400 motors, KM55 4in1 ESC running AM32 v2.21, 3S 1300mAh battery.

  1. ESC telemetry seems very low res
  2. ESC voltage seems to track analog measurements, to its resolution limitations
  3. ESC current seems way off. I expect to see less than 1/4 of BAT[0].Curr: this is one of 4 ESCs, plus FC and servos draw their own current. 57A mean seems implausible.

Log here: https://www.lib.aero/hosted/tmp/qwiktune-rp.bin

newplot
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2

KM55 has only one current sensing resistor, so reported current is same for all motors and equal to total current of ESC. I guess this is usual case with most ESCs.

However this looks like some offset is used in ESC. Not sure why. To report negative current (in case of active breaking props).

3

ESC reports double the peak and almost four times the mean current of the analog current reading on FC.