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BB8 motor gear rpm?

Hi all, new here,

I built a static BB8, now trying to build a moving v.2, and one guy used two 12v 500rpm motors, and my question is, isn’t better a motor with box reducer? On the other side, a 12v 60rpm, with high torque I suppose, wouldn’t be too slow?

Also, is there a big torque difference, between a 6v 100rpm and 12v 100rpm? This is my first robot project, if anyone can spare some time and help, I’d be very thankful. :) 

 

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6V vs 12V is not enough info. I would expect the torque rate to be specified for every motor. 

The one of 12v 500rpm is 6kg-cm. The 6v vs.12v 100rpm was an example, but the 12v-100rpm is 3kgf-cm. I’m considering maybe a 12v 83rpm with torque 11,1kg-cm. I want to connect to a receiver, as it needs also a servo, Unless I decide to use Arduino and L293D. And if I use two motors, will I need battery packs for each, or one 11.1v will work fine?

Thanks.

We need a lot more information to help you out.  

I built a static BB8, now trying to build a moving v.2, and one guy used two 12v 500rpm motors, and my question is, isn’t better a motor with box reducer? On the other side, a 12v 60rpm, with high torque I suppose, wouldn’t be too slow?

Also, is there a big torque difference, between a 6v 100rpm and 12v 100rpm? This is my first robot project, if anyone can spare some time and help, I’d be very thankful.

A 12V, 500 rpm motor almost certainly has a reducing gearbox attached.  Typical speeds for motors without gearboxes are between about 3000 and 20,000 rpm.

We have no way of knowing if a 60 rpm motor would be too slow since 1) we don't know what it's connected to to make the robot move, and 2) we don't know how fast you want it to go.

As ggallant hinted at, 6V and 12V and the rpm tells us nothing about torque.  You might have a 12V, 100 rpm motor the size of your fingernail that focuses your camera, or you might have a 12V, 100 rpm motor that is the size of a loaf of bread and starts your car.    Both are 12V and 100 rpm, but one has a LOT more torque.  The physical size of the motor and the power it uses (power P is volts times amps) will be a better indicator, but even that isn't the complete story.  With two identical motors that have different gearing, one say to 500 rpm and one to 60 rpm, the lower rpm one will produce more torque.  You trade speed for torque.  But the voltage alone says almost nothing about torque.

If you give us a lot more details about how you are building this thing and what you want it to do (such as how fast) we can begin to help.

 

Thanks for the answers, I keep researching, but sometimes is hard to find important details. About my built, would be axis x with a motor, while axis y has another, for point rotation. Similar to this one: https://youtu.be/iQ_PKRjQpDY. It’s a simple build. The speed I had in mind is 0.30m/s, or close. Only worries me, one motor may not be enough to guide the body straight but to veer off? If happens, I’ll have to add a 3rd motor. 

It’s total weight, I hope to reach 2,5~3kg (with all mechanics in), and 45cm diameter. Sorry for the newbie questions, trying to learn all I can. I really appreciate the patience and help :)