Motor spins much faster when they armed by mavros

#1

Hi guys, I have experienced weird situation.
Before start, my settings are:

Pixhawk4 with PX4 FMU V5
NVIDIA Jetson TX2 Development kit
Communication by serial port(TX2) to TELEM2 port according to http://dev.px4.io/en/companion_computer/pixhawk_companion.html

When I arm the motor with RC in MANUAL mode, motor spins at PWM_MIN, which is very natural result.
However, when I arm the motor with MAVROS in OFFBOARD mode, motor does not spin at PWM_MIN. It seems to spin much faster than armed by RC.

Is it natural? I’m not sure whether it is safe to equip propeller to the motor in this situation.

#2

I’m not too familiar with offboard mode, but it could be that offboard mode is considered an auto mode, in which case the parameter MPC_THR_MIN dictates the minimum thrust, rather than MPC_MANTHR_MIN as in manual mode.