Dear friends
I'm trying to control 50 small stepper motor using arduino. My project consist of controlling each motor position independently.
Motors works as no load but for a long time continuously.
My main concern is to control them with single Arduino if possible and to implement things such a way that be able to use stepper libraries like "Accelstepper" or default "stepper" library for Arduino! I know I need about 4x50= 200 pin so I'm thinking about using IO expander boards (I2c or SPI ones) or maybe shift registers.
I've seen similar question in the forum but without any conclusion.
I want to know the best way.
Any suggestion is appreciated.
Thanks
I strongly suspect that a single Arduino could not produce enough steps-per-second for 50 motors - maybe not even for 10. And using port expanders makes extra work for the Arduino.
When you combine the motion of all the motors what is the maximum number of steps-per-second that you will require?
An Arduino Mega has enough I/O pins for about 15 motors. Maybe if you have 6 Megas with 5 controlling 10 motors each and the 6th to send commands to the others?
In this link there is a wiring diagram that allows a 28BYJ-48 motor to be controlled with two I/O pins. I have not tried it myself. It may be a way to reduce both the number of Arduinos required and the computations needed to produce steps.
...R
It would be cheap and very efficient to have one Arduino Pro Mini clone per motor. You can buy them for less than US$1 in quantity.
I would use a common serial bus to send commands.