Methods for "multiplexing" stepper motors?

userHead tanal.gaov 2023-08-04 13:56:34 335 Views1 Replies

This might be more of a circuit/mechatronics question but I'm helping a peer with an arduino project and trying to figure out a solution to eliminate cost/complexity. Right now the project uses 40 small stepper motors that get driven between one of two set positions, each has a dedicated stepper driver resulting in 40 individual drivers. It seemed like there should be a way to still allow for this control while needing only two (or at least many fewer) stepper drivers. It is important that any permutation of motors in the two positions can be made and at this point in the design I can't do much about the drive mechanism, like have simpler individual "selector" actuators and a single main drive mechanism. However the application doesn't require a lot of speed or really any coordination between motor positions, just that they all end up in their designated position.

I was thinking of trying to essentially "multiplex" the driver signals - so that just two motor drivers ran the step signals and then the gating between the driver and motors allowed different selections of motors. I figure I need to be mindful of both signal speed and power draw of the up to 40 motors needing to be driven "simultaneously" which would thwart some possible options I initially considered...

Is there a "plug-in" control solution for something like this, maybe something that is applicable to the "mechanical pixel" display projects? Or maybe I can set up something with a bank of simple transistor gates and multiplexer? Would very much appreciate any suggestions from the sub and/or resources for learning more about this type of mass-motor control.