Techniques for animation have existed but work for certain professions of it like 3d, 2d, stop motion etc. For the emotions or expressions can be shown through a 3d printer.
   First you would have to create a mesh (in a sense, blueprint) for it to be run by the printer. All through Maya May I remind you.
For a realistic emotion you would want to print into smaller bits. (This is all to be used in stop motion). The "bits" are essentially the lower face, then middle, then up. It won't come out the greatest so that's why sanding and smoothing will be needed for the final part. Then combine.
   This all shows even though the old ways of filming are not used as much that now day technology can be used to improve the efficiency and quality of the animation. If and when I do stop motion (also if I have a 3d printer) I would use these methods of creating these models