Any situations where space and weight constraints are important. BLDCs are becoming as cheap as brushed motors and can provide more torque for the same weight. Robotics is seeing a large shift to brushless motors to get more torque per weight and size of motor. A BLDC can also be miniaturized much more easily than a brushed motor and this helps in very tightly confined spaces such as drones and small robotic actuators. Brushless DC motors are also more efficient than brushed motors and are becoming used in many areas where power consumption is important. BLDCs can also spin faster than brushed motors and as one example, are enabling higher speed disc drives in a smaller package than a regular brushed motot. Lastly the lifespan of a brushless motor is longer than a brushed motor since there are no brushes wearing out, so BLDCs are replacing brushed motors in mission critical military systems such as drones and ground vehicles.
