Page 351 - Mechanics of Microelectromechanical Systems

338 Chapter 5
Problem 5.6
The microdevice in Fig. 5.69 combines electrostatic transverse actuation‚
longitudinal sensing‚ and two folded-beam microsuspensions. The actuation
unit is defined by: The sensing
unit has the following parameters: The
sensed capacitance change is for a voltage of 100 V actuation-
supplied. Determine the model displacement of the central shuttle mass‚ as
well as its real displacement for

Figure 5.69 Microdevice with electrostatic transverse actuation‚ longitudinal sensing and
folded-beam suspensions

Answer:

Problem 5.7
A torsional microdevice‚ as the one sketched in Fig. 5.70‚ is employed to
measure the magnitude of an external magnetic field B‚ which is directed as
shown in the same figure. The rotation angle is measured experimentally by
optical means and its maximum value is The radius of the current
loop is the current is and the parameters defining the
two constant cross-section torsion microhinges are
and G = 62 GPa. Find the external magnetic field B.

Figure 5.70 Electromagnetic-field sensor with two torsional microhinges