Page 162 - Mechanics of Microelectromechanical Systems
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3. Microsuspensions 149
The out-of-the-plane definition stiffness is found by applying a force at the
free point of the spring in Fig. 3.16, perpendicularly to the plane of the figure.
This stiffness is the ratio of the applied force and the resulting deflection to its
equation is:
2.3.3 U-spring with Filleted Corners (Configuration # 3)
Configuration # 3 is sketched in Fig. 3.17 where the middle segment is
composed of two quarter-circles encompassing a straight line such that overall,
this spring configuration is made up of five segments.
Figure 3.17 U-spring design with circularly-filleted corners
For a thin configuration where the radius-to-width ratio R/w is larger than
10, and in the case where all segments have the same constant cross-section,
the in-plane compliances can be determined by following the procedure that
has been used for the other U-spring configurations. Their expressions are:
