Stepper motor 1, direct zeroing the way device a suspended stop at zero, and then make the stepper motor drive towards zero Angle, big enough when step motor back to zero, is blocked by stop, the motor end bearing is zero. The zero method is simple, but when the motor is stop blocking, still can do zero drive motor, thus not only can cause damage to stepping motor and actuator, also occur severe vibration and large noise. 2, sensors, the way to device at zero hall switch, photoelectric diode, such as position sensor, when the stepper motor back to zero, the sensor signal is given, the control circuit detects the signal, the motor stops in the zero position. The zero to precise, reliable, but increased the complexity of the circuit, the device has certain requirements. 3, using a special motor drive belt stalling test chip, the chip when the motor stalling, the motor can be detected immediately halt, so as to determine the zero position. But the way poor universality, for stepping motor's winding current phase has certain requirements, and this method cannot be used in a microstep driving mode.