Arduino Project Planning

[aeroencychris]

Hi all,

I have a rough plan for an upcoming project, but I just wanted to run it by you all before I proceeded any further.

 

I have a NEMA-17 stepper motor (not specifically from Adafruit but here's the type: https://www.adafruit.com/product/324) that I need to drive from an Arduino, preferably something small like a Nano. My plan was to get some cheap offbrand one from Amazon that supports 12V input, directly solder a regulated power supply to the Vin pin, and then use that same 12V source to drive the motor. I didn't want to have to deal with a whole Uno motor shield, so I found this TB6612 breakout board that should (from my understanding) be able to drive the motor as detailed in this guide (https://learn.adafruit.com/adafruit-tb6612-h-bridge-dc-stepper-motor-driver-breakout/overview).

 

Also, I'm a bit confused as to how to attach anything to the stepper motor shaft. It looks like one side of the round shaft is flat to allow something to mount onto it, but I haven't found any sort of hardware to do this. Could I just 3D print something that could snugly slide onto it?

 

My main concern is finding a reliable but cheap Nano clone as well as using the same 12V source to drive the Arduino and motor. Do any of you see any glaring problems with this before I proceed with purchasing?

[Silverwolf_7]

You will need a mosfet or motor controller like the one you linked to drive the motor from the arduino. Wire a voltage regulator in parallel with the source to drive the arduino while pulling 12v from the source to drive the motor controller. As for attaching something to the motor shaft it depends on your use. A 3d printed object would work depending on how much torque will be applied to it. Usually a set screw goes against the flat face of the motor shaft through the side of the hole to prevent the sprocket or gear from shifting. Pretty much any nano clone will work or maybe I'm just lucky with mine. Out of curiosity what are you trying to make?

[albyDNC]

On amazon you can find cheap good Arduino-compatibles (http://a.co/dNAWEL4). To drive your stepper motor I suggest you use the stepper drivers made for 3D printers (A4988 or DRV8825). The shaft of the motor has flat side to tighten screws on it; you can 3D print gears and sprockets, but it depends on how much torque you need! obviously print them in ABS 'cause PLA is too weak. You can find metal gears on eBay and Amazon btw.

[aeroencychris]

10 hours ago, Silverwolf_7 said:

You will need a mosfet or motor controller like the one you linked to drive the motor from the arduino. Wire a voltage regulator in parallel with the source to drive the arduino while pulling 12v from the source to drive the motor controller. As for attaching something to the motor shaft it depends on your use. A 3d printed object would work depending on how much torque will be applied to it. Usually a set screw goes against the flat face of the motor shaft through the side of the hole to prevent the sprocket or gear from shifting. Pretty much any nano clone will work or maybe I'm just lucky with mine. Out of curiosity what are you trying to make?

Do I really need a regulator, or can I just assume the power supply will do well enough? It takes in a whole range of voltages with 12 just being its max, but I guess I'm not sure how big of an issue that really will be. Better safe than sorry?

 

Not entirely sure what you're trying to say with the screw. I'm just rotating a large 3D printed (maybe even mostly out of wood) circular platform which will rotate on the same axis as the motor. Eventually I'll just lay objects on the platform so that they'll rotate with the motor (doing stuff with photogrammetry)

[aeroencychris]

27 minutes ago, albyDNC said:

On amazon you can find cheap good Arduino-compatibles (http://a.co/dNAWEL4). To drive your stepper motor I suggest you use the stepper drivers made for 3D printers (A4988 or DRV8825). The shaft of the motor has flat side to tighten screws on it; you can 3D print gears and sprockets, but it depends on how much torque you need! obviously print them in ABS 'cause PLA is too weak. You can find metal gears on eBay and Amazon btw.

First post  welcome to the forums!

I believe the stepper motor I'm using is for a RigidBot 3D printer. Still not sure what you mean by the screw but I shouldn't need any gears for this since I'm just laying a platform ontop of it which will rotate on the same axis.

[albyDNC]

As you can see in the image, there is a screw on the gear; this screw is used to tighten the gear on the flat side of shaft and lock it.

[aeroencychris]

38 minutes ago, albyDNC said:

As you can see in the image, there is a screw on the gear; this screw is used to tighten the gear on the flat side of shaft and lock it.

I'm not sure how I'd mount anything to that piece though. Just 3D printing something snug would be ideal for me but I don't see how it would fit onto that metal piece. 

[Silverwolf_7]

3d printing a part will be fine, the set screw is more for if the motor is on its side. As for the regulator you will need to power the arduino with 5v as well as whatever voltage the stepper driver needs. Most arduinos will burn up if you try to run 12v through them. Assuming the stepper driver needs 12v you will either need 2 powersupplies (one 5v the other 12) or a regulator to bring the 12v down to 5v for the arduino.

[aeroencychris]

4 hours ago, Silverwolf_7 said:

3d printing a part will be fine, the set screw is more for if the motor is on its side. As for the regulator you will need to power the arduino with 5v as well as whatever voltage the stepper driver needs. Most arduinos will burn up if you try to run 12v through them. Assuming the stepper driver needs 12v you will either need 2 powersupplies (one 5v the other 12) or a regulator to bring the 12v down to 5v for the arduino.

A lot of the Arduinos I'm seeing say they accept up to 12V, plus a lot of boards like the Uno literally have DC jacks on them for 12V. If you think the 12V source might not be stable then that's a different issue

[Silverwolf_7]

I stand corrected they can take 12v.