SparkFun Forums

[crash2020]

I want to drive a stepper motor, such as your ROB-13636, using an Arduino and a driver such as your EasyDriver.
I will be using 12v and I need to achieve at least 120 rpm (low load).
I will actually be driving two motors, but not simultaneously.

Will the EasyDriver work for me? Presumably I will need two, one for each motor?
Are there other alternatives that would be better? I prefer one driver card to two, if possible.

I tried the
Motor Shield Kit for Arduino v2.3
Product Code : RB-Ada-94
from RobotShop (supports two motors), but the max speed I can get from that shield seems to be about 40 rpm.

The project does not have be Arduino-based, if some other platform will be better, such as Raspberry Pi (or even Pi Zero).

If my prototyping goes well, I hope to repeat my build about 1000 times, so I'd like to get started on firm ground.

[Valen]

What is 'low load'? Can it turn with the desired RPM with no load at all? Like in free air, just a paper or cardboard disk attached to the axle. If it can, how much is it slowed down with the desired load. And what is it that it should be driving.

The EasyDriver has a current limiting potentiometer. It set's the maximum current through the windings. (700mA) Whether or not that is reached depends on your power supply. You have not mentioned it's amp-rating, only that it is 12 volt.

[crash2020]

Thanks for your reply.

By "low load", I mean "unloaded" ... just turning an axle + soda straw. My target load will be a bit more, but not a lot ... something like ejecting a Hershey candy bar in a couple of seconds (via driven wheel).

I'm using a 12V x 2A lithium battery, but that's negotiable. I can up either the voltage or amps or both. What I need is a bit more speed .. just a factor of 3 would do nicely. I've seen some vids of fancy/custom boards that drive these motors crazy fast.

I am hoping there is an off-the-shelf board/shield that will do the trick -
stepper motor, such as your ROB-13636
RPM of at least 120 (light load: Hershey bar at 3 inches/sec)
12V x 2A (negotiable)

[Valen]

12V, 2 A seems to be enough. Atleast for one. Have you adjusted the potentiometer and noticed any effect? It is basically free running so loading or lack of current should not be a problem.

The stepping speed of the motor would then be dependant on the clock rate with which the EasyDriver board is fed. Also if microstepping or another mode is applied. That comes from how control pins are set on the Easydriver and what clock signal is generated by your Arduino (or whatever) through (software) generated pulses on a (timer)pin on. That means you should show the code that you use.

[theropod]

This thread might help even if the application is completely different.

https://forum.sparkfun.com/viewtopic.ph ... ope#p81405

R