Editing Stepper motor (section)

===Microstepping===
What is commonly referred to as microstepping is often ''sine–cosine microstepping'' in which the winding current approximates a sinusoidal AC waveform. The common way to achieve sine-cosine current is with chopper-drive circuits. Sine–cosine microstepping is the most common form, but other waveforms can be used.<ref>[http://www.zaber.com/wiki/Tutorials/Microstepping zaber.com], microstepping</ref> Regardless of the waveform used, as the microsteps become smaller, motor operation becomes smoother, thereby greatly reducing resonance in any parts the motor may be connected to, as well as the motor itself. Resolution will be limited by the mechanical [[stiction]], [[backlash (engineering)|backlash]], and other sources of error between the motor and the end device. Gear reducers may be used to increase resolution of positioning.

Step size reduction is an important step motor feature and a fundamental reason for their use in positioning.

Example: many modern hybrid step motors are rated such that the travel of every full step (example 1.8 degrees per full step or 200 full steps per revolution) will be within 3% or 5% of the travel of every other full step, as long as the motor is operated within its specified operating ranges. Several manufacturers show that their motors can easily maintain the 3% or 5% equality of step travel size as step size is reduced from full stepping down to 1/10 stepping. Then, as the microstepping divisor number grows, step size repeatability degrades. At large step size reductions it is possible to issue many microstep commands before any motion occurs at all and then the motion can be a "jump" to a new position.<ref>{{cite web|url=http://www.micromo.com/media/wysiwyg/Technical-library/Stepper/6_Microstepping%20WP.pdf|title=Microstepping: Myths and Realities - MICROMO|website=www.micromo.com|access-date=2024-10-07|archive-date=2016-12-06|archive-url=https://web.archive.org/web/20161206092700/http://www.micromo.com/media/wysiwyg/Technical-library/Stepper/6_Microstepping%20WP.pdf|url-status=bot: unknown}}</ref> Some stepper controller ICs use increased current to minimise such missed steps, especially when the peak current pulses in one phase would otherwise be very brief.