I would suggest making the motor a third component completely, with just a standard form of drive shaft coming out of the valve box and a set of predrilled attachment points (metric & english) so that a variety of motors can be attached, based on what can readily be manufactured/improvised locally. Then some manfacturers can make valve boxes and others can adapt whatever motors they are already setup to produce to be attached to any such valve box, if the attachment is standardized.
Or instead of shaft protruding from valve box, have an opening where attached motor shaft with its own cog inserts into the valve box to engage internal cog when assembled, with size & offset of motor cog providing some gear ratio flexibility. Would be nice to hear from a medical person whether something this crude would be helpful in the worst case...
-- Kevin Huscroft on Agorize
I was actually imaging a setup just like this where the shaft of the motor drives the timing belt (or gears) and is simply mounted to the valve manifold, not actually part of the component itself.
(reposting this here for visibility)