Overall hardware structure advice

Hi there,

Before I get stuck into learning the right code, I wanted people's take on the right hardware structure for an upcoming build.

I want to control at least six 9-12v motors performing similar rotation and actuation functions that demand precise timing and speed (up to 500rpm) manipulation, each via their own external control panels which feature knobs and buttons that relate to those parameters. All of them will also be controlled in unison at times by an overall control panel.

What are your immediate thoughts on the hardware that would require? MEGA? DUE? Motor shields? If so how many? What's the way to bring in those other control panels? How many motors could I conceivably get going with this type of setup?

Any nifty software that would aid my quest?

I need the motors to be as reliable and durable as possible- therefore dc, servo or stepper?

Any questions, just ask

Many thanks for your time,

Jim.

functions that demand precise timing and speed (up to 500rpm)

Definitely steppers, in my opinion. Add positional accuracy.

What are your immediate thoughts on the hardware that would require? MEGA? DUE? Motor shields? If so how many? What's the way to bring in those other control panels? How many motors could I conceivably get going with this type of setup?

I would start with an Uno and 1 or 2 steppers. Once you understand how to operate 1 and add a second you will know what you need for many. You give no idea of the power required so I can't recommend any motors or drivers. Nema 17 motors and their drivers are widely available and cheap.

Any nifty software that would aid my quest?

If you are doing manual control (knobs and switches) you will need to write the code. The AccelStepper library will help.

Please describe the project that the motors will be part of. At the moment your question is not much different from “how long is a piece of string”

And if the minimum is 6 motors, what might the maximum be?

What is the power (watts) of the motors?

Do you need bi-directional control of the motors?

How precise does the speed control need to be? Why?

What do you mean by “precise timing” - when each motor starts? or stops? or how long it runs for? And what is the maximum acceptable timing error in milliseconds?

…R

groundfungus: Definitely steppers, in my opinion.

Isn't that a little premature?

...R

Isn't that a little premature?

Yes.

Thanks so much for weighing in you two. I realise I’m a snake trying to swallow a warthog right now so to speak. I’m sorry if I can’t spell the project out precisely right now.
Perhaps if I can remove a few variables we can all understand things a little more…

  • 6 is a starting number for what I hope to be up to 15 motors
  • Let us assume they are Nema 17’s (12V, 350mA). These seem close to what I am after.
  • They will need to rotate both ways with as much accuracy as affordable (I’m not a millionaire but I’m not homeless either).

Looking towards that total of 15, what Arduino should I be using? Are ins and outs the only consideration or is processing power(considering each motor will have its own external controls) going to go up and therefore the Arduino required change the more motors I add?

What other hardware will come into play here- drivers? Motor shields? Something else to connect the control panels?

Just point me in the right direction and I can do the reading from there.

Thanks again,

Jim.

Stepper basics should answer a lot of your questions.

For the controls, there are many tutorials on line for interfacing Arduino to momentary switches, pots, encoders, etc.

wolvesjim: Thanks so much for weighing in you two.

You still have not told us what the project is.

Without knowing that how can we give sensible advice?

I have some 12v 350mA steppers controlled by Pololu A4988 stepper drivers and usually powered from a 19v laptop power supply - it's the highest voltage I can conveniently lay hands on.

Each stepper motor needs two connections to an Arduino for Step and Direction so 15 motors would need 30 connections and would require a Mega rather than an Uno. However there are other things to consider and a big question must hang over the ability of a 16MHz Arduino to produce pulses fast enough to satisfy the needs of 15 motors.

So ... tell us what the project is all about.

...R

groundfungus: Stepper basics should answer a lot of your questions.

Thanks. I thought I had included it myself.

...R