The mask I'm trying to build will display different lighting patterns. The overall goal is to synchronize these patterns with a musical/dance performance, so there were two options: either hard-code the sequence in the microcontroller or equip the mask with one or two sensors so the change of patterns can be triggered by the wearer.
I decided to "explore" the second option first. Tracking jaw movements (how open the mouth is) and maybe the cheeks (or lips) might make it follow the speech organically. Would a Flex sensor be a good idea for sensing (vertical) jaw movements? Note that it is supposed to be a cloth mask, so thats why I'd like to avoid making a hinge and equipping it with a potentiometer for precise angle tracking.
What could I do about tracking the cheeck/lip movent? I need only a couple of states, nothing precise. A strain sensor, perhaps?
I hope I was able to convey my question, if not please let me know
EDIT: I apologize, but I omitted the fact that it is supposed to be a portable, real-time system.