Page 174 - Mechanics of Microelectromechanical Systems
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3. Microsuspensions 161
The out-of-the-plane definition stiffness will again consider bending and
torsion, and is calculated by applying a force at point 1 in Fig. 3.31. Its
equation is:
Example 3.11
A bent beam serpentine spring and a bent beam spring occupy the same
square area. Which of the two microsuspensions is the stiffest in terms of the
main stiffness assuming they are built of the same material and they have
identical cross-sections ?
Solution:
Both springs are inscribed in a square area of side The definition
stiffnesses for the two springs are expressed by inversion of the
corresponding compliances of Eqs. (3.88) and (3.20), respectively.
Figure 3.32 stiffness ratio comparing a bent beam spring to a serpentine bent beam
spring
By considering that:
