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Author Topic: Help:Choosing stepper motor for Micromouse  (Read 3519 times)

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Offline evilknight007Topic starter

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Help:Choosing stepper motor for Micromouse
« on: December 08, 2007, 11:09:07 AM »
HI fellas..  ;D

i have just started my micromouse and need help in choosing the right  stepper motor . For now i have planned to make a bot of size 10*10cm with two ball castors in the front and back to support the two wheels driven by stepper motor in the middle .
The chassis is to be of sheet metal of thickness 2mm .

I can't decide which motor to buy to pull a weight of around .75-1kg including the batteries . All i have access to is the surplus shops in my locality and the motors there doesn't have any voltage or current readings .have already tried out two motors but it just doesn't seem to have enough torque . The shaft stops rotating even if i just hold in with my hand .
 ??? :-[

Can anyone pls suggest a suitable motor for this.

Thanks .

Offline Rebelgium

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Re: Help:Choosing stepper motor for Micromouse
« Reply #1 on: December 09, 2007, 05:49:07 PM »
You need to have a motor with a gearbox, you can't just attach a wheel to the motor, you need a gearbox to reduce the speed and increase the torque.

And .75-1kg for such a small robot is very heavy. are you sure about those numbers?
And why are you using 2mm metal sheets, .75-1mm will be enough...
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Offline evilknight007Topic starter

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Re: Help:Choosing stepper motor for Micromouse
« Reply #2 on: December 09, 2007, 09:59:01 PM »
The weight figure is only approximate . The motors itself would come around 200gms each .And with batteries and chassis i'd say the figure is very realistic .

And u say tat i need to get stepper motors with a gear box?? Haven't seen anything like that yet. (MAN !! Its a pain in the a**
getting parts here in India.)

My knowledge about steppers is very limited which brings me to this question.
Does motors with high voltage means high torque or with high current rating means high torque.??
I got a motor with the following specs :
4.2Volts, 850mA per coil, Unipolar , 3.8degree step angle .
Will this produce enough torque. ??

Offline ed1380

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Re: Help:Choosing stepper motor for Micromouse
« Reply #3 on: December 10, 2007, 03:15:02 PM »
you'll need to find out how much lb/in or kg/cm torque it makes and use admin's calculator
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Offline Admin

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Re: Help:Choosing stepper motor for Micromouse
« Reply #4 on: January 20, 2008, 04:54:48 PM »
any luck with it?

considered maybe using a regular DC motor with an encoder?

Offline paulstreats

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Re: Help:Choosing stepper motor for Micromouse
« Reply #5 on: January 20, 2008, 05:15:45 PM »
ive decided to use these myself http://www.sparkfun.com/commerce/product_info.php?products_id=8420
They have a holding torque of 2.45kg

 


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