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                                                 Resonant Micromechanical Systems

                                                             Resonant Micromechanical Systems  241








                                         8
                                                                                 10
                              error [%]
                                          0
                                          1
                                                                              c w

                                                   c l
                                                                      1
                                                                   10
                              Figure 5.13 Percentage error in the bending resonant frequency:  model  I predictions
                              against model II predictions (paddle microbridge).








                                       1.5
                                                                               10
                              error [%]
                                         0
                                          1
                                                                              c w

                                                   c l
                                                                    1
                                                                 10
                              Figure 5.14 Percentage error in the torsional resonant frequency: model I predictions
                              against model II predictions (paddle microbridge).


                              diminish as the dimensions of the middle segment increase compared
                              to those of the end ones.
                                The relative errors between the torsional resonant frequencies—Eqs.
                              (5.30) versus Eq. (5.38)—are plotted in Fig. 5.14 in  terms  of  the
                              nondimensional parameters defined in Eq. (5.12), and for a baseline
                              geometry of t = 1 ȝm and w  = 5 ȝm.
                                                       1
                                For  the  selected parameter ranges and  baseline parameters, the
                              errors in the torsional resonant frequency when ignoring the inertia
                              contributions from the two compliant end segments are smaller than




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