2 steppers and 1 dc motor?
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2 steppers and 1 dc motor?

by brawo on Tue Nov 13, 2012 4:03 am

hi,

i'm new to this and i've read that the adafruit motor shield can support up to 1 stepper and 2 DC motor.

would it be able to support 2 steppers and 1 DC motor?
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Re: 2 steppers and 1 dc motor?

by brawo on Tue Nov 13, 2012 4:04 am

oh another question. and if the adafruit motor shield is unable to support 2 steppers and 1 DC motor

then is there any motor shield out there that could support my intended configuration?
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Re: 2 steppers and 1 dc motor?

by adafruit_support_bill on Tue Nov 13, 2012 5:40 am

The Adafruit Motor Shield has 4 H-bridges. Each stepper requires 2 and each DC motor requires 1. So if you have 2 steppers, there are no free bridges to control an extra motor.

Your options depend a little on what kind of control you need for the DC motor. If you need only speed control (one direction rotation), you can control the motor with a simple MOSFET and any free digital pin. If you need both direction and speed control for the motor, then you need a full H-bridge controller.

Pololu has a range of motor control modules you could piece together to handle a wide variety of motor combinations.
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Re: 2 steppers and 1 dc motor?

by brawo on Tue Nov 13, 2012 6:37 am

thanks for the reply!

i have

2 stepper motors with ratings of 5V and 0.57A
1 DC motor with rating of 5.6V and 0.67A

which require both speed and directional control

i'm not exactly sure how to implement the MOSFET board to the circuit i was intending to have. sorry but could you recommend a motor shield / motor controller that could be added on to the arduino uno rev3 whichcould do both speed and directional control?

or say give a link to a picture/schematic on how the circuit might look like?

thanks for the help man. much appreciated
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Re: 2 steppers and 1 dc motor?

by adafruit_support_bill on Tue Nov 13, 2012 6:52 am

If you need both speed and direction on the DC motor, then the MOSFET solution won't work. You can still control the 2 steppers with the Motor Shield. You could add something like one of the Pololu "simple" motor controllers, or one of the smaller motor driver carriers to handle the DC motor.
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Re: 2 steppers and 1 dc motor?

by brawo on Tue Nov 13, 2012 12:07 pm

ok thank you for your help!

oh is there a recommended current sensor? say if i wanna sense current for all 3 motors. what current sensor do you recommend?

i understand that the adafruit motor shield does not have an in-built current sensor?
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Re: 2 steppers and 1 dc motor?

by adafruit_support_bill on Tue Nov 13, 2012 12:13 pm

These work well: https://www.adafruit.com/products/904
The tutorial shows one connected to a motor shield: http://learn.adafruit.com/adafruit-ina2 ... out/wiring
Image
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Re: 2 steppers and 1 dc motor?

by brawo on Wed Nov 14, 2012 5:26 am

Oh ok that helps thank you!

Mmm I just found out from a supplier that the stepper motor I'm using isn't compatible with the adafruit mototshield.

Just to be sure are there any stepper and DC motors that would be incompatible with the adafruit motor shield?

What would be the characteristic of a motor that is compatible with the motor shield?

Thank you for entertaining my questions!
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Re: 2 steppers and 1 dc motor?

by adafruit_support_bill on Wed Nov 14, 2012 5:44 am

The shield can handle unipolar or bipolar steppers with up to 06A/phase. Based on the spec you quoted earlier, I would think they are compatible.
2 stepper motors with ratings of 5V and 0.57A

Do you have a link to a spec sheet?
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Re: 2 steppers and 1 dc motor?

by brawo on Wed Nov 14, 2012 8:20 pm

http://www.velmex.com/pdf/mc/Vexta%20PK ... 20data.pdf

Its the first line item the one ending with AA

Ya the seller said I might be unable to control the motor.
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Re: 2 steppers and 1 dc motor?

by adafruit_support_bill on Wed Nov 14, 2012 8:54 pm

OK. 0.67A is above the spec for the L293D chips on the Adafruit Motorshield. But there are options. Check out "I need more power!" in this FAQ: viewtopic.php?f=31&t=26873
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Re: 2 steppers and 1 dc motor?

by brawo on Wed Nov 14, 2012 9:04 pm

Ok so that means if I replace the original one with SN754410 I would then be able to control my stepper? Soooo that means it'd possible?

Haha thanks a lot then. Ok so basically as long as the steppef motors adhere to the ratings required which is 0.6A/phase or in this case a 1A/phase current from the other chip and meet the minimum voltage requirements then it should be able to be powered by the motor shield right?
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Re: 2 steppers and 1 dc motor?

by brawo on Thu Nov 15, 2012 4:05 am

Hi,

ok another question. what if i want to control 3 stepper motors using the adafruit motor shield? is there a recommended controller?
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Re: 2 steppers and 1 dc motor?

by adafruit_support_bill on Thu Nov 15, 2012 6:17 am

Pololu have a nice range of stepper controllers. Using one of the serial interface models, you can easily add another motor.
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Re: 2 steppers and 1 dc motor?

by brawo on Thu Nov 15, 2012 9:06 am

ok thanks

by the way for the 3 current sensors right. i understand that i can connect 1 current sensor to analog pins 4 and 5 of the adafruit motor shield.

then where do i connect the other 2 current sensors? is there a schematic for this?
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