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5. Static response of MEMS 335
The normal stresses in this case are produced by the two bending moments‚
and the maximum value occurs again at one vertex being of the form:
Figure 5.65 Model of a U-spring: (a) geometry and static loading; (b) cross-section
Because the cross-section is narrow‚ the tangential stress which is caused by
the torsion moment has its expression given in Eq. (5.198).The von Mises
theory results in:
which‚ by using Eqs. (5.200) and (5.201)‚ gives
For this state of stress problem‚ the Tresca criterion becomes:
The numerical data of this problem results in
Problems
Problem 5. 1
The precision-positioning microdevice shown in Fig. 5.66‚ utilizes
transverse electrostatic actuation and a spiral spring. The displacement is
