Concerning the application of forces and measurements of displacements on
microsctrucutures:

Electrostatic actuation provides an excellement method of applying distributed
loads to microstructures. Our group has done a lot of work in this area --
specifically in papers by Osterberg et al at MEMS 94, Hilton Head 94, and in
his recently completed PhD thesis (request from oster@mtl.mit.edu). Measuring
displacements accurately is another question. Optics and capacitance are
obvious choices, and we have on-going work in both arenas. (I should comment
that we have emphasized measurement of pull-in voltage rather than continuous
measurement of displacement in our work to date -- we now are moving on to the
issue of displacement measurement.) At present we are exploring a vision system
which has been developed by Dr. Dennis Freeman of MIT for this purpose. If we
have a breakthrough, I will share the news.

Steve Senturia, MIT
sds@mtl.mit.edu