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Topic: How many steps are in a stepper motor? (Read 20765 times) previous topic - next topic

gnozahs

Oct 12, 2011, 09:15 pm Last Edit: Oct 12, 2011, 11:15 pm by gnozahs Reason: 1
So I'm trying to use a stepper motor for a hw assignment and I'm new to the arduino world. I was reading tutorials about stepper motors online and I'm trying to figure out if there is a set number of steps for a whole revolution for a stepper motor?

I was reading this tutorial and the guy put 96 steps for one revolution. Is this universal or is every stepper motor different?
http://pscmpf.blogspot.com/2010/07/arduino-stepper-motor-control.html

Code: [Select]
#include

//create an instance of a stepper motor object
Stepper stepper(96, 8, 9, 10, 11);

void setup()
{
// set the speed of the motor to 10 RPMs
stepper.setSpeed(10);
}

void loop()
{
stepper.step(96); //on revolution
delay(2000); //wait 2 seconds
}


*edited. Mistakenly put servo motor instead of stepper motor.

AWOL

There are no 'steps' in a servo, they are analogue devices.
The resolution depends on the quality of the components used.

ckiick

You have confused stepper motors and servo motors.  They are two different things.  Do some reading.

Photomankc

Hobby servos have a pot that acts as a position feed-back so they are analog and as smooth as the output pulses and the pot quality allow for as said above.  Other servos used for linear positioning have shaft encoders so they do have a notion of resolution, how many encoder ticks they can sense per revolution, for use in feedback but they don't operate in "steps" at all.


Grumpy_Mike

Quote
So I'm trying to use a servo motor for a hw assignment

Guess you are on an F so far.

gnozahs


You have confused stepper motors and servo motors.  They are two different things.  Do some reading.


Ah crap. Yes, I was still thinking about servo motors from my previous project. What I meant is stepper motor. Is there a set number of steps for a stepper motor to make a full resolution?

Grumpy_Mike

Quote
Is there a set number of steps for a stepper motor to make a full resolution?

No,
for full steps there are two normal resolutions 7.5 degrees per step and 1.8 degrees per step but there are others. I think the 1.8 degrees is most popular as this works out to be 200 steps per revolution. However, you can drive them with micro steps giving 2, 4, 8 or 16 micro steps per real step.

gnozahs


Quote
Is there a set number of steps for a stepper motor to make a full resolution?

No,
for full steps there are two normal resolutions 7.5 degrees per step and 1.8 degrees per step but there are others. I think the 1.8 degrees is most popular as this works out to be 200 steps per revolution. However, you can drive them with micro steps giving 2, 4, 8 or 16 micro steps per real step.


Oh. I did notice on the side of the stepper motor it has 7.5 degrees printed on it. So what does that mean?

Grumpy_Mike

It means 7.5 degrees per step or 360 / 7.5 = 48 steps per revolution. They are sometimes called a 'tin can' motor because they are constructed from two sheet metal shells connected together with tabs. The are not very accurate but are low cost.

gnozahs


It means 7.5 degrees per step or 360 / 7.5 = 48 steps per revolution. They are sometimes called a 'tin can' motor because they are constructed from two sheet metal shells connected together with tabs. The are not very accurate but are low cost.


Thanks! I get it now.

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