Page 245 - Thomson, William Tyrrell-Theory of Vibration with Applications-Taylor _ Francis (2010)
P. 245
232 Lagrange’s Equation Chap. 7
7-18 The rigid bar linkages of Example 7.1-1 are loaded by springs and masses, as shown in
Fig. P7-18. Write Lagrange’s equations of motion.
Figure P7-18.
7-19 Equal masses are placed at the corners of the frame of Example 7.1-2, as shown in Fig.
P7-19. Determine the stiffness matrix and the matrix equation of motion. (Let I2 = l\ )
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y /7 ///, 'y / / / / / / / / / / Figure P7-19.
7-20 Determine the stiffness matrix for the frame shown in Fig. P7-20.
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Figure P7-20.
7-21 The frame of Prob. 7-20 is loaded by springs and masses, as shown in Fig. P7-2L
Determine the equations of motion and the normal modes of the system.
/r72 c/2
Figure P7-21.
