Stepping motors

From CandyFabWiki

Stepping motors, also known as Stepper motors, are brushless, synchronous electric motors that are stable in a fixed set of positions. The motor's position can be precisely between these fixed steps, without any feedback mechanism, under open-loop control.

Because they are able to advance to a given position without feedback, they are often used as a low-cost alternative to servo motors.

[edit] Advantages

• Cost. Stepper motors are relatively inexpensive to produce and purchase.
• Simplicity of drive. Stepper motors can be driven by a relatively easy "binary" switching on or off the coil currents. Unipolar stepping motors in particular can be driven by simply closing switches in a set order.

[edit] Drawbacks

• Inaccuracy. In a number of circumstances a stepper motor may fail to make a step when requested or overshoot the set position because of momentum. A common solution is to introduce a position sensor or a full feedback mechanism, effectively defeating the cost advantage versus servo motors.

• Noise. The rapid pulsing of coil currents can make stepper motors into effective speakers.

(This article is a stub. Please help us to improve it.)