In the equation above, n is the rotate speed of motor ,U is
the armature voltage of the motor, R is the external series
resistor of the armature circuit, is the magnetic flux of
the armature circuit, Cm is the motor torque constant, and
Ce is the induced electromotive force constant of motor. By
adjusting the armature voltage-U can change the rotate speed
of motor-n. In the EMB system, the frictional braking
strength is controlled through changing the output of the
torque motor