Advice on controlling stepper motors

[Jmac68]

I am building a robot that will incorporate approx. 10 stepper motors. I will also be controlling two mass flow controllers. I was advised that the ChipKit Max32 would work for me. I wanted to confirm this. I was previously considering using a Arduino Mega but was told that the processing power is insufficient. Question #1: Does this board output PWM 0-5v? With the Mega I was going to put a low pass filter on one of the outputs to control my mass flow controllers, which can be controlled with analogue 0-5v. Next question: If I do use this board do I need to use a unique stepper controller with each stepper motor? And if so what model/type of stepper controller would be most suitable? I'm using Nema 17 Bipolar steppers. Also, some of the stepper motors will be running simultaneously during the sequence. Also any suggestions on writing code would be appreciated. Thank you very much for any help with this. I am very new to all of this and there's a lot to learn!

[JColvin]

Hi Jmac68,

The chipKIT Max32 does not output PWM from 0-5V. All of it's pins including the analog pins operate from 0 to 3.3V. Most of the pins are 5V tolerant, but are not actually able to supply 5V.

As for the individual stepper controllers for each stepper motor, that really depends on your design. If all of your motors are going to be running and turning exactly the same way, then you could in principle use the same stepper controller. However, based on the way stepper controllers are designed (such as a Darlington Transistor Array or a L293DD or any number of other chips based on how powerful your stepper motor is), you would then also probably be sending power through the same pins on the chip for all of the stepper motors, which will likely not be strong enough to have that much power flowing through it to power all of them. With 10 stepper motors, I would recommend using individual stepper controllers (based on my personal knowledge and experience; other people may have a more experienced recommendation).

As for the code recommendation, I might be able to offer some advice on what kind of things you would want to do, but in the end you know the setup the best. What exactly are the stepper motors doing? Are they the things controlling how much mass is flowing through your system based on the feedback from the mass flow controllers? Are they inside the mass flow controllers? Or something else entirely?

Thanks,
JColvin