Hello fellow roboteers, I am getting back into stepper motors after a few years of being out of the loop. Looking at RobotShop’s stepper motors, they don’t give any step size with the motors. Is there a reason for this? TIA.
Hello @Robert72,
At which exactly stepper motor were you looking in the shop?
I am looking now at some of them, and they have step sizes defined on a web page. For example:
Thank you for your reply . You are correct the standalone stepper motors have a step angle, however the stepper motors with gearbox do not?
Then you can find a step value for a motor without gearbox and then calculate your angle step based on gear ration.
For example:
Thanks again for your reply, although I am not convinced. I can not identify the motors as individual units. Would be easier if they just included the step size on the page. I think we have to assume they are all 200 steps.
You’re welcome.
Anyway, just provide for which product (part number, name or link to it) from shop you have a question, and someone will answer.
Hey @Robert72
Welcome to our community!
Do you have any examples?
I’d gladly explain you what are the steps angle for these motors.
Thanks @Robert72!
In this case, the stepper motor is a 200 steps that has 1.8°, to get to the total of 360°.
When using the step angle in calculations, you should derive the exact step angle by dividing 1.8° by the gearbox reduction ratio.
This motor has an integrated planetary gearbox with a 99 1044/2057 :1 ratio, which like it is said in the specifications, give a step angle of 0.018° after the gearbox.
You could have simply multiply the step angle 0.018° by the gear ratio and you would get the typical step angle, which is ~1.8°.
But if you want to know how many steps you would need for a revolution after the gearbox, then you would need to divide 360°s by 0.018° = 20,000 steps.
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So the motor has a step angle of 1.8°, and a step angle of 0.018° after the gearbox. So the gearbox has a ratio of 100:1? You said the gearbox has a ratio of 481.8:1. Which is it, it can’t be both? Or am I missing something?
Yes, motor has a step angle of 1.8°, and a step angle of 0.018° after the gearbox. And yes, gearbox has a ratio of 100:1. You are not calculating this 481.8:1 the correct way because the numbers are not shown correctly. Use 100:1 as a result.
Hi Robert,
The ratio is 99 + (1044/2057) : 1 = 99.507535… : 1
You can approximate it to 100:1. The step angle at the end is 0.018° after the gearbox.
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OK thanks for the replies. I appreciate the help.
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