Page 288 - Mechanics of Microelectromechanical Systems
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5. Static response of MEMS 275
Equilibrium about the local and axes results in the equations:
and the motion of the midpoint P to the final position P’ is expressed by
means of the equation:
By using the following small-displacement assumptions:
the solution to Eqs. (5.22) and (5.23) gives:
These amounts enable calculation of the final position (point P’) as:
where and are the displacements of the midpoint P after application of
the actuation force
Example 5.5
Evaluate the errors that correspond to ignoring the suspensions’ stiffness
about the z-direction in a two-suspension MEM. Determine the actuation
force which is necessary to make this error zero.
Solution:
In the case where Eq. (5.25) becomes:
