I cannot find a proper way of controlling multiple step motors (say 100) with arduino. Im using a cheap steppermotor 28BYJ-48 together with driver ULN2003A.
I need to coordinate all 100 with individual input once. I have successfully done it with servos by chaining this:
but since they are controlling pwm this is not a solution working with stepper motors. If there are no workaround letting me using pwm signal to control steppers?
An option would be to continue to use servos but since steppermotors seems like a more reliable and accurate way of doing it over time I have started to investigating using steppers instead.
Any hint on how to do this?
The control of stepper motors is very different from servos. Each motor needs its own ULN2003 and each ULN2003 needs 4 connections to Arduino I/O pins. An Uno (or nano) could control 3 motors. A Mega could control about 15 - however if you need fast step rates it may not be able to produce steps for that many motors at a fast enough rate.
You should also be aware that a stepper motor has no sense of its own position (whereas a servo has) and you will need a limit switch for each motor that can be used at startup to detect when the motor is at the HOME or ZERO position. That means 5 connections per motor.
My suggestion is to use a series of Unos (or nanos) (3 motors to each) and use another Uno to control them all over an I2C connection.
Or just stay with the servos.
...R