This paper summarizes the characteristics and advantages and disadvantages of the stepper motor motor
There are two ways of moving the motor, one, four phase four; Two, four phases eight. Four phase four stepper motor step Angle may take twice than four phase eight, but may take smaller than four phase eight control precision, four phase under the same pulse frequency is twice as fast in four. To figure out the speed of a four-phase, eight-shot operation, you need to understand two basic concepts first. 1, take count: the number needed to complete the periodic changes in A magnetic field pulses or conducting state expressed with n, or refers to the motor turns A pitch Angle pulse number, four phase motor, for example, there are four phase four operation modes is AB - BC - CD - DA - AB, four phase eight beats operation mode is A - AB - B - BC - C - CD - D - DA - A.
Step Angle: corresponding to a pulse signal, the angular displacement of the rotor of the motor is expressed in theta. Theta = 360 degree (the number of rotors), in the case of the normal two and four phases, the rotor teeth are 50 teeth motor. Four run time interval Angle is theta = 360 degrees/(50 * 4) = 1.8 degrees (commonly known as a whole step), eight beats runtime interval Angle is theta = 360 degrees/(50 * 8) = 0.9 degrees (commonly known as half step). These two concepts clearly, after we again to calculate the rotational speed, with basic steps within 1.8 ° Angle of stepping motor as an example (now in the market of conventional two, four basic steps from the Angle of the hybrid stepping motor is 1.8 °), four phase eight running mode, each receives a pulse signal, around 0.9 °, if receive 400 pulses every second, so speed is 400 megabits per second x0. = 9 ° 360 °, equivalent to turn every second, every minute 60. Other things can be calculated.
The answer to your question is a big one, and if you take a copy of the book for homework, the teacher won't miss you. In theory, the more accurate the accuracy the better the more stable the machine, but the more complex the structure of the motor (which is the simple answer). Nowadays a lot of mechanical structure are replaced by electronic circuit, if you choose a 128 subdivision drive, take a stepper motor control effect certainly had no words, so don't obsess to achieve mastery through a comprehensive study
