Page 192 - Mechanics of Microelectromechanical Systems
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3. Microsuspensions 179
where l is the total length of the spiral.
Problems
Problem 3.1
The poly silicon fixed-guided beam of Fig. 3.4 has a length of
and a constant rectangular cross-section with and
Young’s modulus is E = 150 GPa. The beam is used in an accelerometer
whose measuring unit can read displacements with a precision of
What is the minimum force that can be detected by this microsystem ?
Answer:
Problem 3.2
An inclined beam is used in a static application where the stiffness about
the active direction of motion‚ is two times smaller than it should be.
Determine the inclination angle of the beam that would achieve the stiffness
objective (see Fig. 3.6 (b)). Known are
Answer:
Problem 3.3
The ratio of the stiffness to the stiffness of a bent beam spring‚ as
the one sketched in Fig. 3.9‚ has to be of a fixed value r. What is the length of
the beam’s square cross-section side that would produce this result and what
is the permissible range of r ? Consider that
Answer:
and therefore:
Problem 3.4
A U-spring is designed according to the prescriptions of configuration #
1, Fig. 3.12. It has a constant rectangular cross-section with and
