If you were to place two or more (preferably more for 3d analysis) as far apart as possible you would be able to determine rotational accelerations and axis of revolution by differential comparison. (Assuming gyros are not available). I just found out about the project and I was thinking about how I would go about it and that would be a must as things like whiplash will have a different axis of rotation (ie the neck) as opposed to part of a blow being converted into rotation movement around the vertical axis. This could also be done with multiple gyros (to determine the exact axis of rotation). Im curious if one could sustain high impact to a helmet but have it go into rotational energy and not get a concussion but rather pull or break their neck
All that said I came here looking to see if it is possible to decrease apparent noise density by using multiple MEMS.