Page 37 - Mechanics of Microelectromechanical Systems
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24                                                          Chapter 1


















                               Figure 1.16 Fixed-guided beam


         At the  same  time, the  deflection   can  be  expressed by  means of
          Castigliano’s displacement theorem, Eq. (1.70), as:







          The bending moment at the generic position of abscissa x is:





          It can be seen in Eq, (1.75) that the partial derivative of         in terms of    is
          x. As  a  consequence,  Eq. (1.74)  permits  solving  for  the unknown
          namely:





          In order  to find the slope at  midspan, a dummy moment  is artificially
          applied  at point 2  in  order to  enable  performing  calculations by  means of
          Castigliano’s displacement theorem in the form:








          The bending moment will have two different equations one  for each of the
          intervals 1-2 and 2-3, namely:
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