BLDC motors require electronic commutation. The motor controller must read the current angle of the motor so that it knows which phases U V W to enable via six

BLDC motors require electronic commutation. The motor controller must read the current angle of the motor so that it knows which phases U V W to enable via six MOSFETs. An ESC can cheat by reading out the back EMF but this only works once the motor has started spinning, such as in a drone, but in a robot arm that is supposed to hold its position.